This PDF file contains the front matter associated with SPIE Proceedings Volume 12493, including the Title Page, Copyright information, Table of Contents, and Conference Committee information.

An analysis of wide-range temperature sensors based on Silicon Carbide (SiC) Schottky diodes, with Ni and Ti contacts, is presented in the paper. The impact of Schottky contact inhomogeneity on sensing performances is thoroughly analyzed. Sample diodes are parameterized using our recently developed model, focusing on evincing practical device performances. Electrical behavior of the structures can thus be accurately modeled over wide temperature ranges using only a minimal set of parameters. Based on the evaluated diodes’ performances, architectures for temperature sensors with both proportional (PTAT) and complementary (CTAT) variation coefficients are discussed. Sensitivity, linearity and temperature errors are determined in all cases.

Supramolecular PEDOT∙CB7-PS polypseudorotaxane and PEDOT∙CB7-PR polyrotaxane were prepared by threading the cucurbit[7]uril (CB7) molecules over the 3,4-ethylenedioxythiophene (EDOT) monomer, followed by oxidative polymerization . The dielectric parameters of these encapsulated compounds were investigated by means of broadband dielectric spectroscopy. The evolution of dielectric constant with frequency clearly emphasizes two distinct regimes, assigned with the space charge polarization (at low frequencies) and the ‘intrinsic’ dipolar activity (at high frequencies). The spectra of dielectric loss vs. frequency reveal a dominant signal for conductivity of free charge carriers. Furthermore, frequency dependences of conductivity profiles are strongly correlated with the dielectric constant and dielectric loss components and disclose the clear signal of electrical conductivity. The conductivity of PEDOT∙CB7-PR was found to be with one order of magnitude higher than that of the pristine PEDOT.

A new dinuclear complex Europium(III) bis[(μ2-ethoxy)(benzoyl trifluoroacetonato)(nitrate) (1,10-phenanthroline) europium(III)]2 1,10-phenanthroline, here after [Eu(μ2-OC₂H₅)(btfa)(NO₃)(phen)]₂·phen)(1) (Figure 1a) and the mononuclear complex Eu(TTA)₃(Ph₃PO)₂(2) (Figure 2a) were synthesized and characterized by photoluminescence (PL) spectroscopy. The PL emission spectra of the powder samples of the compounds were recorded in the temperature range 10.7 – 300 K. Both complexes show rare metal-centered luminescence in the energy range characteristic of the Eu³⁺ ion (580 – 710 nm) with emission bands according to ion selection rule. The emission bands in the PL are attributed to the internal 4f → 4f radiative transitions of the Eu³⁺ ion ⁵D₀ → ⁷Fi (i = 0→4) and, in addition, to the splitting of each level caused by the influence of the electric field of the ligands of the complex. Due to the splittings, each level is divided into 2i+1 sublevels, which are well observed in the mononuclear compound 2 centered at 580, 595, 615, 650, and 698 nm. However, in the PL spectrum of the dinuclear compound, the splits show a double number of splits (2(2i + 1)), which indicates the presence of two positions of the Eu3+ ion in the molecule and which are not optically equivalent.

The experimental results obtained in this paper was made by investigation of water samples collected from different zones of Ialomita River to characterize the quality indices of water. Salinity, electrical conductivity and other physicochemical indicators of samples (pH, turbidity) were investigated in the order to establish the real pollution degree of Ialomita River. The heavy metals concentrations containing Pb, Cd, Zn, Ni, Cr, Mn, and Fe were determined by Flame Atomic Absorption Spectrometry (FAAS). The obtained data confirmed that heavy metals are coming from various pollutant sources and the main anthropogenic sources were industrial waters and municipal wastewaters pathogenic which include organisms, plant nutrients, synthetic organic chemicals, inorganic chemicals, microplastics, sediments, oil etc.

Doping of calcium phosphate glasses from the ternary system SiO₂-CaO-P²O₅, with transition metals ions makes them to acquire additional properties, of a prophylactic nature (anti-inflammatory, healing, antimicrobial). This paper presents the microbiological study performed of three glass compositions synthesized by sol-gel method, one doped with silver, the other doped with copper II, compared to a control sample, with the same compositional matrix, but not doped, in order to highlight their antimicrobial character and the determination of the minimum bactericidal dose of each type of glass on two strains of bacteria with high pathogenic potential.

In this paper, an impact study of the consequences of uranium mining on the Caraş Valley was carried out and includes the radioactive effects of uranium mining activity, as well as the monitoring, remediation and post-closure program of environmental factors. The experimental part highlights the influence of the exploitation of uranium deposits on the soil and vegetation. By bringing uranium ore to the surface, in the areas where it is handled or transported, an influence on the environment is highlighted by increasing the content of natural uranium and decay products from its family in environmental factors. Soil and vegetation are directly contaminated by the storage of sterile ore, poor ore, ore storage or radioactive waste; either indirectly by contaminating the air or water causing soil and vegetation pollution. [1]

The paper presents: the terminal’s infrastructure, the loading’s plans, the equipment’s details, the operational data onboard, the systemic analysis of the terminal. In order to highlight the operational optimization in the cargo terminal, operating scenarios are proposed, to which simulation models are attached. Enter parameters such as towing units, return / load / unload speed, the distance between parallel and opposite parking rows and the load pick-up time, using working diagrams. It simulates the operability in the terminal. In the analyzed terminal, the expected size of the ship is not found in the equations attached to a simulation model, because the degree of berth occupancy is actually related to the number of access points, where a frame can be placed and not the length available berth. The terminal usually operates by scheduling ships in advance and therefore arrival times are usually planned in advance and follow a strict schedule. The simulation results (performance indicators) lead to the estimation of the values for the optimal quay time, in relation to the number of units for loading in the proposed scenarios. It takes into account whether the arrival pattern is random or scheduled and the time of service provided by the terminal. Also, the different types of goods and their distribution on the quay are identified and taken into account. A methodology for assessing the level of service provided by the terminal under certain operational constraints is also provided, in part, as a by-product of the methodology.

Container terminals are the actual backbone of break bulk cargo transport around the world. Pressure by supply chains, coupled with the rapid growth in cargo amounts, result in an ever-increasing demand for productivity optimizations in this highly competitive market. Within short time windows, many cargo handling processes occur in parallel, and operational decisions should take into account both time efficiency and equipment utilization. Waterside operations consist in handling of containers by quay cranes, land based guided vehicles and yard cranes. The container relocation problem that minimizes the number of moves needed to retrieve all containers, while respecting a given order, is studied in parallel with the quay cranes scheduling to find an optimal sequence of crane operations that perform the required container movements. Starting with real data from Constanta Container Terminal, and studying the statistical relevance between operational indicators and applied inverse statistics as a pertinent tool for waiting time expectancy. In the paper is proposed a simulation based-optimization process viewing the dynamics of the Container Terminal as a complex system, because during operation, many sources of disturbance and uncertainty exist. Possible designs are investigated in the framework of Bayesian optimization and Simulated Annealing of the proposed time convergence algorithms. The research in the paper is based on real data from Constanta Container Terminal, and studied the statistical relevance between operational indicators and applied inverse statistics as a pertinent tool for waiting time expectancy.

The novelty in this work consists in the identification of constructive solutions for bearing the main shaft with mounting in three and four support points. Improvements to the existing bearing construction solutions for existing turbines are also presented. As the bearings perform their function, which is essential to the mission inside the current turbines, with MW installed powers, dynamic stresses and unpredictable stresses lead to costly premature repairs. For the benefit of the wind industry, the reliability of the main shaft bearings needs to be improved. ^{[1], [2], [3]} The market demand motivates the development of new technical solutions for the replacement of standard radial thrust roller bearings in three-point bearing turbines, such as wear-resistant radial roller bearing roller bearings and two-row radial tapered roller bearings, pre-stressed ^[4]. For this reason, this work presents some constructive solutions that are efficient in the wind turbine industry. Also, there are presented some mode of failures, like: the incipient stages of micro exfoliation of the working surfaces of a two-row radial roller oscillating roller bearing in the main shaft of a wind turbine, insufficient lubrication, the simulations of different stages of distributions of pressure on inner and outer rings, equivalent (von Mises) stresses and an another improved construction solution of bearings.^[4] In conclusion, the criteria for choosing the types of reliable wind turbines imply a special attention in choosing reliable bearing elements, with long operation times and as few repair / maintenance costs as possible. ^{[5], [6]}

The paper analyzes the tools for establishing the ecological status of marine ecosystems in the context of climate change. The novelty of the paper is the use of mapping applications to obtain information on the intended study location such as: data on the physical properties of ecosystems, how many types of habitats, lists of indicators and links to relevant publications and reports. The working tools are specialized programs. The results are descriptive indicators of the analyzed ecosystems: Biota, Phytoplankton, Benthic flora, Fauna, Benthic fauna, ichthyofaunal, Marine mammals, Seabirds, the number of indicators per related water column habitats, the number of indicators on seabed habitats, the number of indicators per habitat type for specific and non-specific taxonomy, the number of indicators depending on the existing pressures in the area. As a working method, we can highlight both frequently used tools (the risk matrix, the vulnerability) and a new tools (software) for assessing the state of the environment, which allows the assessment of the health of marine systems. The methods used can be validated for different locations. The following were analyzed: ecosystem status characteristics, pressures and impacts, risk matrix for a marine ecosystem, risk assessment, anthropogenic impact on marine ecosystems, a model and descriptive indicators of good ecological status of the ecosystem, as well as vulnerability. The obtained results are: the descriptive indicators for Black Sea marine ecosystem, the assessment of ecological status of the marine ecosystem, the risk matrix and vulnerability.

Heat exchangers are thermal devices used in several industrial applications. Parallel flow arrangement means that both fluids flow stream is in the same direction. Low thermal conductivity of traditional fluids affects in a negative manner the efficiency of heat exchangers. In order to overcome this drawback, literature recommends the use of nanofluids. This paper deals with a theoretical study of performance enhancement of a double pipe heat exchange with parallel flow arrangement. The analysis consists in a comparison between the situations in which the water and the water base nanofluid (Al₂O₃-water) are the cooling fluids. The cold fluid is a nanofluid (NF)- represented by Al₂O₃ nanoparticles added to water. The diameter of nanoparticles is 25 nm and the considered volume concentration is of 0.25%. The hot fluid is water. The nanofluid flows in the outer pipe, while the water flows in the inner pipe; fluids flow with constant inlet temperature: 32°C – for the nanofluid and 58°C – for the water. The volumetric flow rate varies in the range: 0.5÷1.9 L/min. The obtained results show that the average values of the following: heat transfer rate, effectiveness, inner and outer heat transfer coefficients, all for the nanofluid, are about 16%, 10%, 16% and respectively 17% higher in comparison to the base fluid. The analysis will reveal the fact that a better performance of the heat exchanger it is achieved when using Al₂O₃-water nanofluid as a cooling medium than when using the base fluid (water), due to the higher thermal conductivity of the nanofluid.

Vapour compression refrigeration systems (VCRS) are present in various applications of refrigeration; they work with high power consumption and rise environmental concerns. Important features of VCRS working with R134a are reflected in significant energy consumption and environmental issues. This is why the analysis of performances terms, such as power consumption and Coefficient of Performance (COP), is mandatory. The adoption of nanorefrigerants is a promising step towards new working fluids to be used in refrigeration systems. The environmental issue specific to the traditional R134a can be diminished by replacing it with nanorefrigerants- resulted by adding of nanoparticles to the pure refrigerant (R134a). Traditionally used R134a contributes to the global warming. This problem is associated with the need to improve the efficiency of the plant. The solution is the adoption of a new refrigerant: the nanorefrigerant. This paper focuses on the performance improvement of VCRS working with R134a and R134a/Al₂O₃. The theoretical comparison is developed considering the evaporator temperature of –10° C and a condensing temperature in the range (30÷50)° C. The performance of the system is analysed in terms of work consumption and COP. Since the adoption of R134a/Al₂O₃ will reveal a gain in the energy efficiency (13%) when rising the condensing temperature, the analysis will continue with the performance assessment when the concentration of nanoparticles will vary in the range (0.05÷0.50)%. Results indicate that a 10 times increase in Al₂O₃ concentration will lead to about 77% decrease in work consumption.

Implementing of high efficiency quantum teleportation protocols is in the key task for development of accessible and secure quantum communication. For a successful quantum teleportation two conditions should be satisfied: fidelity of teleportation greater then 1/2 for pure states and the existence of the entanglement between resource state modes during all teleportation process. Quantum teleportation using Gaussian states is a perspective direction because they can be easily implemented and manipulated using laser radiation. The simplest case for the continuous variable quantum teleportation represent teleportation of a pure state. However the thermal noise cannot be eliminated from the system, and the thermal component should be taken into account. In this work we put in evidence how the increase of average thermal photon number influence the fidelity of teleportation of a Gaussian state. We use Lindblad master equation and covariance matrix formalism to describe the temporal evolution of studied system and to put in evidence dependence of the fidelity of teleportation on the environment conditions and resource state parameters. As well we calculated the entanglement between the resource state modes to check if all conditions for a successful teleportation are satisfied.

In the context of the development of quantum technology, most asymmetric encryption algorithms managed to be broken using Shor's algorithm, while symmetric encryption algorithms, such as AES-256, are believed to be unbroken for the moment, Grover's algorithm has been able only to reduce AES brute force attack time to its square root. This paper proposes to present how Quantum technology can affect current security algorithms and analyze how it can be used to improve our data protection by developing new algorithms. Quantum cryptography alongside Quantum key distribution could be a deal-breaker by using new encryption algorithms and providing new solutions to different cryptographic tasks that are known to be impossible by using normal computers. In the end, it will be discussed how the concept of quantum teleportation could provide new, faster, and much more secure solutions in telecommunication compared with the ones based on radio technologies.

This paper presents aspects related to use of cylinders with two piston rods. Besides that, in this article are presented four schemes for a double acting cylinder with in and out piston rod. There are presented one pneumatic circuit and one electropneumatic scheme. First pneumatic scheme comprises following devices: compressed air supply, air filter, 4/2 way valve, two throttles valves and a double acting cylinder (Cylin 1-1). The second pneumatic scheme comprises following devices: compressed air supply, start-up valve with filter control valve, 5/2 way valve, two throttles check valve and two double acting cylinders (Cylin 2-1 and Cylin 2-2). Furthermore, the first electro-pneumatic system comprises following devices: compressed air supply, air service unit, 5/2 way solenoid valve, two throttle check valves, two double acting cylinders (Cylin 3-1), two relays, two valves solenoid and two lamps. Finally, the second electro-pneumatic system has the following devices: compressed air supply, automatic drain filter, 5/2 way solenoid valve, double acting cylinder (Cylin 4-1), Grafcet PLC, sequential function chart (SFC) and two magnetic proximity valves. The design and simulation of the both circuits from this manuscript is done using FluidSim software from Festo.

Tracking the maximum power point (MPP) represents the essence of the variable speed control of wind turbines since it determines their efficiency. The MPP is achieved by always adapting the wind turbine’s speed to the wind speed. This paper presents a study of methods to improve the control of wind turbines. One of these methods is the minimization of the time interval required for the wind turbine to achieve maximum power. Minimizing the time it takes to bring the speed/VUM, ω, from GE to the optimum value, ω_OPTIM, is made at the maximum value for GE current. The study is based on the wind speed measurements collected from a wind farm located in Dobrogea, Romania. In this paper we have studied the methods of optimizing the control of wind turbines with an emphasis on minimizing the time required to bring wind turbines in the optimal area, from an energy point of view knowing the wind speed and, based on this, the optimal mechanical angular velocity, charges the electric generator, (at the rated current value), if 𝜔⋗ 〖ω〗 _OPTIM, or discharges, (zero power), if 𝜔⋖ 〖ω〗 _OPTIM. This ensures maximum wind energy capture. The study is based on the wind speed measurements collected from a wind farm located in Dobrogea, Romania.

The development of sensors and control and command modules capable of extracting environmental data has made it possible to build an underwater drone for monitoring and collecting water samples from hard-to-reach areas. In this paper we present the project that focuses on the fundamental challenges related to communication, control but also the analysis of water parameters in real time.

Fluctuations in the level of the incident wave at the level of the measurement sample can lead to erroneous interpretations of the absorption domains. The paper attempts to draw some conclusions regarding the level changing of microwave radiation generated by the Gunn diode at various polarization voltages. This work described a signal level fluctuations as well as areas of unstable operation of the Gunn diode for various voltage values and frequency spectra.

In many industrial applications we need small dimensions dc-dc power convertors with a high integrated scale circuit. A lot of applications require ability to be connected at different DC power supply sources. In this scope we are using dc-dc power convertors. This power convertor requires a large input supply voltages and also the drop voltage over power converter must be as small as possible. In these days it is possible to achieve this goal by using high integrated scale microcontrollers and small power MOSFET transistors. The new microcontrollers have enough computing power to ensure a fast application response and they integrate a lot of hardware modules (analogue to digital converters, timers, pulse width modulation modules) that allow us to minimize the schematic. The new MOSFET transistors are able to support high voltages and they can be driven with low control voltage. This new advantage recommends them to be used in power applications. The schematic is very simple and all the control and computation algorithms are implemented in microcontroller software. The microcontroller requires a low power consumption. The schematic is implemented using surface mount technology in a single module. The module dimensions are very small. The power module recommends to be used to power a lot of electronic modules, electric devices (like inductors, valves i.e.) for industrial automation and operation.

Industrial environment can be easy improved using audio message devices. These devices, programmed with different messages, can impress the human factor and can help the operators in areas where lamps cannot be installed or are not visible. These devices will be connected in cloud through IoT technology. The status of the devices is controlled from cloud or local using digital signals. The device contains a controller that includes IoT technology and Wi-Fi connection board to ensure connectivity with Internet. The messages are pre-recorded into message player. Player is connected with a local audio amplifier.

The fourth Industrial Revolution (Industry 4.0) has been used to describe the digitalization of industry, which will inaugurate integrated marketplaces and supply chains, an era of automated systems, interconnected factories, and advanced technologies that will combine the physical, digital, and biological worlds. In order to advance in this new paradigm, European industry must develop decentralized, self-organizing intelligence at the factory level, network-driven value chain integration, disruptive digital technologies, and sustainable manufacturing strategies and methodologies. It is critical that the shift to cyber-physical systems occurs without a loss of productivity, and that companies are incentivized, benefit from decreased cycle time and production costs, higher yield performance, and greater energy efficiency and sustainability. In this paper we will present 3 projects that we were part of: Multi-AI, ADMA TranS4MErs and SMART-PDM. ADMA TranS4MErs will help factories transition to Industry 4.0 by addressing environmental, digital and societal concerns, Multi- AI will bring a defect detection and anomaly prediction solution and SMART-PDM will give diagnosis and prognosis information. All these solutions will not only change how factories work, but will decrease costs, there will be less waste, parts used and there will also be improvements in quality of the products that leave the factories.

Searching the intelligent aspects and identifying the rules in the huge amount of data automatically created nowadays is an appropriate method to explore and understand a world that is becoming more complex. Fortunately, the means of investigations are synchronous with the actual level of technological development. One might remark that, computer science being a rapid development field, it became an inspiring environment for other domains of science. The paper presents data mining techniques, original implementations of the linear/quadratic regression and of the K-means clustering methods and two machine learning models using the “Microsoft Machine Learning Studio (classic)” software. Some of the conclusions are: the data input process is simple and flexible, making it possible to access a wide range of data sources; there is an important library of algorithms that can be easily included in the experiment; data control may be thoroughly done using various methods, including visualizations; the machine learning application offers reliable results; the output consists of several types of reusable ‘objects’: trained models, data in various formats, web services. The paper is an important stage on the path of a trust development process which is intended to finish by considering machine learning instruments as common instruments in engineering.

Huge amount of data is generated nowadays by many and various sources and their management is a problem of high importance in science, especially in research and development. Complex phenomena can be accurately modeled using various sources of large amount of data which either cross check the models, or improve their accuracy. Data management is an important issue in actual modeling context, which must be solved at both, concept level and applications' layer. The paper presents a ‘checklist’ of questions to be answered when the data management layer of a new computer aided model must be conceived and implemented. Moreover, finding the rules of the ‘game’, i.e. the best policies for the rapid development of the data management foundation of the models leads to a valuable knowhow in the rapid composite models’ development or even in hybrid models’ development. The paper presents the conclusions of a thorough study of the MySQL, Oracle, Microsoft SQL Server and MariaDB RDBMSs. A subsequent study will approach MongoDB, Amazon DynamoDB and Databricks in order to synchronize the models’ development requirements with the actual cloud approaches: IaaS, PaaS and SaaS. To conclude, in the huge volume of data actual conditions, an intelligent data persistency strategy within a model is a goal for a smart and visionary analyst, who is, according to Blaise Pascal, a “thinking reed”, i.e. “Man is but a reed, the most feeble thing in nature, but he is a thinking reed”.

In the current business environment, organizations of all sizes, regardless of their area of expertise, are vulnerable to a substandard level of understanding the implications of delayed or missing preventive actions, corroborated with the prevalence of security incidents. The article aims to provide an in-depth analysis, visually facilitated by the Fault Tree Analysis of physical access vulnerabilities, to propose solutions based on the authors’ multidisciplinary expertise in order to tighten security protocols, and to assist organizations to be in compliance with international regulations and standards. Consequently, organizations will improve their reputation and customer assurance, avoid security violation-related fines, strengthen their internal confidence, boost the marketing and sales prospects, and ensure business continuity, by implementing security controls based on procedures and policies as part of an ISMS, providing the necessary training for all personnel, and enforcing multi-layer physical security systems, with a focus on restricted areas, facilitated by the usage of a redundant structure comprised of thermal cameras, movement sensors and improved Velostat keypads.

Precision agriculture is one of the global agricultural industry's new orientations. According to surveys, food demand is increasing significantly while production remains stagnant at present levels, making a food shortage more likely in the near future. The purpose of this article is to propose a solution for developing and implementing a monitoring platform for precision agriculture. The goal is to enhance product quality and boost productivity by implementing modern 5G technologies and autonomous Unmanned Aerial Vehicles (UAVs). The platform will employ specialized high-precision WSN (Wireless Sensor Network) sensors that will connect with the Cloud platform through a 6LoWPAN end -to-end protocol. Analyses have also been performed on the processing of the data and images collected with WSN and UAV, employing specialized classification algorithms to determine the risk of disease incidence, such as Random Forest and SVM (Support Vector Machine).

The smart agriculture domain refers to the usage of technologies such as the Internet of Things (IoT), sensors, location systems, robots and Artificial Intelligence implemented on farms. The goal is to increase the quality and quantity of crop production while motivating viticulturists to implement new technologies as well as streamline production costs. The study’s purpose is to monitor environmental conditions (soil temperature and humidity, air temperature and humidity) and to analyse diseased leaves from the vineyard using an intelligent, integrated decision support system for vineyard management that is based on the IoT end-to-end solution. This method suggests placing IoT sensors inside wine crops to measure environmental conditions, which are then sent and stored in the Cloud. Also, an Unmanned Aerial Vehicle (UAV) is used to capture images containing healthy and diseased leaves (powdery mildew, downy mildew, gray rot) from various regions of the vineyard. These images are analysed by implementing a Machine Learning algorithm that detects the state of the leaf. Following the analysis, the results are presented as graphs and charts, allowing the viticulturist to proceed with the necessary actions.

Synthetic aperture radar (SAR) represents one of the most popular and advanced remote sensing techniques for Earth monitoring, creating 2D images with a high spatial resolution. It is also notable that it is a system that does not depend on weather conditions or daylight to conduct the data acquisition. The main objective of the paper is to estimate the elevation profile of the scenes, using methods of tomographic processing of synthetic aperture radar images, on Sentinel-1 data. The city of Prague (Czech Republic), along with the surrounding areas was selected as the test region. The urban region will guarantee the high coherence of the acquisitions. To achieve the main objective, a multi-temporal data set will be built, consisting of 20 SAR acquisitions of the Sentinel-1 satellite, suitable for tomographic processing. Each of the 20 images has the same polarization and orbit orientation. For the image pre-processing stage, the SNAP interferometric processor was used. The preprocessing steps consist of: co-registration, generation of the flattened interferograms and their filtering. The final results of these steps were exported to Matlab for further processing. The reflectivity profile of each pixel will be estimated using two non-parametric filters: Beam-Forming and Capon, and the elevation maps of the area will be generated.

Because epileptic seizures may come from different parts of the brain, symptoms can vary greatly between patients diagnosed with epilepsy. Common symptoms are: uncontrolled movements or spasms, convulsions, psychological sensations, loss of consciousness and more. These are usually caused by oscillations of the signals which are transmitted between neurons. The most common method for monitoring these types of seizures is the EEG. Although is very effective, the patients have to wear electrodes attached to their head, which causes discomfort and limits their movements. The main purpose of this paper is to establish if an electronic device attached to the patient hands or legs, can detect and monitor the periods of seizures. The device consists of a small microcontroller and a motion sensor which can detect and store any movement of the user.

IoT is expanding into all aspects of our lives, one of the domains that weren’t explored to their full potential in the past is traffic management, but this is changing fast due to new technologies being rolled out. Improvements in traffic flow with IoT and the new 5G networks are a relatively new domain and focus of this article. 5G opened a new range of possibilities in traffic management with multiple interconnected nodes that can exchange data continuously over any movement speed. Besides speed, 5G provides better link stability and security, vital for traffic management. An improved version of IoT is the Internet of Vehicles (IoV) which is considered an integrated part of smart cities and i s composed of several components that communicate through a wireless communications infrastructure to always have signal coverage. A new alternative to enable such wireless connections is the 5G cellular network. Moreover, our article highlights the innovative SOLID-B5G project along with the latest developments in the IoT - 5G field. The SOLID-B5G project focuses on solving network security issues and adopting flexible, high bandwidth, and low-cost networks, facilitating the interconnection of as many IoT sensors and the simultaneous data collection, storage, and processing processes.

Industry 4.0 defines a tendency of the extensive promotion of the Internet of Things(IoT) in the logistic network, manufacturing and factories. Digitalization of the industry is essential in improving the production process, cost reduction, and raising the associated business. Regarding this, Arrowhead Tools (AHT), an H2020 project, has the objective to automate and digitalize the industry across Europe. AHT (Arrowhead Tools) is developed based on the Arrowhead Framework (AHF), an open-source that conceptualizes the automation and integration of IoT objects to services. AHF implements interoperability of the IoT systems through real-time data management, automatization of scalable engineering systems and security characteristics. After defining the AHT project and AHF architecture, we introduced the concept of tool and toolchain about Industry 4.0 related to AHT. We also present the AHF interoperability and implementation of the Beia-IoT tool alongside the platform VITAL-IoT for the environmental monitoring use case in the industrial sector, which is compliant with AHF.

This paper presents a low-cost smart home system where two types on nodes were developed: the wireless sensor node where the analog or digital sensor is augmented by an ESP32 SoC, and the wired sensor nodes, where the high-power analog or digital sensors are enhanced by the addition of similar ESP32 and an USB or 230VAC power connection. The proposed solution provides features to improve security and quality of life. In addition, we implemented the prediction of the sensor data timeslots which allows energy savings and preventive maintenance (by informing the used when expected communication was skipped)

The quality of the food products that humans consume is a matter of great concern because it directly affects the wellbeing of the consumers. This paper details a low-cost application for the evaluation of the pH values of fresh squishes juices correlated with the quantity of light transmitted through the samples. The juice samples were analyzed using visible sensor and with a pH-meter. The sensor acquires data in the visible domain for six channels between 450 nm and 650 nm. The analysis system was placed within an opaque container to prevent any external light to reach the surface of the visible sensor. Ambiance temperature and humidity within the container were monitored using a digital sensor. The sensors acquired data for three consecutive days. The goal of the application was to identify if there is a correlation between the pH variation and the data acquired with the AS7262 visible sensor. The results have shown that the transmission for the 450 nm channel increases over time for citric fruits (such as grapefruit, lemon and orange), whereas the pH decreases.

The Perception layer in Internet of Things (IoT) architectures is responsible for connecting sensor nodes and data acquisition units such that sensing devices capture relevant data from the corresponding environment. Most IoT platforms are designed to transmit data at fixed time intervals, which is a disadvantage in the modern world dominated by rapid changes in the evolution of events. This paper addresses improvements performed on an IoT platform dedicated to critical applications (e.g., fire, air pollution). This novel approach assumes the use of two equations empirically determined to compute the time interval between successive transmissions depending on the detected event. A new method for communication technology selection (LoRaWAN, Wi-Fi or cellular) is implemented and the time interval between two successive transmissions is adjusted according to the occurring event. Comparisons were highlighted for each analyzed case. The proposed method proved to be suitable for critical scenarios or scenarios that can generate false-positive alarms, due to abnormal variations of parameters.

Recent works have focused on the identification of a type of linearly separable systems owning particular intrinsic symmetric/antisymmetric properties. This problem was formulated based on bilinear forms and Kronecker product decomposition. In this paper, we extend this particular symmetric filter in the context of linear system identification, aiming to estimate more general types of impulse responses. The developed solution is formulated as a Wiener filter, by deriving an iterative version exhibiting better performance features, especially in more challenging scenarios (e.g., limited amount of data and/or noisy conditions). Simulation results obtained in the context of echo cancellation indicate the appealing features of the proposed solution.

This paper analyzes a complex scenario of using the Compact-RIO embedded system to control flexible real-time processes in industrial environment. The described application is around intelligent control path, a very suitable field for the characteristics of the mentioned system. Moreover, the paper gives details about the control algorithm, the testing procedures, including the measurements and the results obtained with a MyRio 1900 module implemented on a robot arm with two servomotors (actuators). The first part presents the MyRio development system with its sensors and actuators. Also, the configuration and programming procedures are clarified in this section. The second part presents the set-up of the stand and the experiments carried out for an application regarding the precise handling of components in the medical area.

In this paper, we propose an obstacle avoidance system that uses a fuzzy logic control algorithm, for mobile robots that use inexpensive IR sensors in order to guide the robot through an unknown environment. The system is programmed in Python, utilizes one fuzzy system for total control and is self-contained. There are many systems made in the past which are mobile robots that used fuzzy logic in order to navigate in an unknown territory. However, those devices either required a wireless connection between the robot and a base station, or said robot used expensive sensors in order to guide itself around, such as ultrasonic sensors, or used multiple fuzzy systems in parallel to achieve the desired behavior from the robot. All of the examples mentioned above were coded in C/C++.

This paper presents a close-range indoor transmitter localization system using a low-cost RTL-SDR setup. The purpose is the detection of illegal radio communications during class exams in a class where radio transmitters might be used. Current experiments are made on FM transmitter localization in 433MHz ISM band but the components were chosen to allow monitoring various frequencies.

Redundancy and fault tolerance are two of the most important considerations in automation control systems, as they provide stability and reliability for the whole system. This paper presents the types of redundancy that can be found in a Programmable Logic Controller (PLC) system at component-level, connection-level, and system-level, and is a review of various techniques and implementations of PLC redundancy, accompanied by a summary of redundancy options offered by PLC manufacturers in the global market.

This paper describes a low-cost system to measure the spectral characteristics of a given light source of unknown origin (without vendor-provided datasheets describing the light source properties). For this purpose, we consider using the AMS AS726X family of cost-effective light sensors, one of the latest generations of smart sensors. The data measured with these sensors is collected by a low-cost embedded system. To maintain the low-cost target, the embedded software is based on open-source code. We first validated the sensors using a set of light sources with known specifications and then extended the measurements using other light sources (including some of unknown origin) and validated the measurements with a higher-performance spectrometer.

Is being studied the electrical behavior of sensor made of Velostat under DC and AC voltage and the influence of magnetic field on this sensor type (does not influence). In alternating mode (AC voltage is applied), it starts from the premise that we can easily analyze the current flowing through a resistor of known value inserted with the Velostat sensor and from here we can deduce the behavior of the sensor. To obtain the location feedback of the touch from Velostat sensor, it was built a device which contains discs and circles made of polylactic acid with a 3D printer and double foil of Velostat material on which eight sheets of copper were attached by lamination. An Arduino board is used to inject small currents into the touch sensor but also to read the potential values at the eight terminals formed by the construction. This way we can determine where we touched the sensor.

Some industrial applications like electrical discharge machining involve large currents and voltages that can lead to severe EMC (electro-magnetic compatibility) problems. These environments are susceptible to large surges of electricity which may potentially damage the sensible modules/devices or may modify commands sent over communication lines. One solution to reduce the magnitude of these problems is the galvanic isolation, especially by using optical medium for sensible signals like switching and discharge commands. The paper focuses on practical aspects of implementing galvanic isolation using optocouplers and fiber optics between microcontroller-based control board and power board with switching devices, as well as measuring the delays on the signal chain.

The ship requires energy for propulsion and for on-board heating and cargo operations. It is necessary to generate electricity on board supplied by the main propulsion engines. Also, the heating and cargo operations on board are supplied by the boiler. While the main engines are shut down at the berth, the auxiliary engines and boilers are kept running to support onboard operations. For example, an ocean-going cruise ship could burn approximately 220 MWh (fuel) every 10 hours to meet the energy demand on board. As a comparison, the main (propulsion) engines of the same ship could use 220 MWh (fuel) to sail approximately 100 km at sea. The ships used heavy fuel oil (HFO) and marine gas/diesel propulsion engines (MGO/MDO) and on-board operations that emit, among others, greenhouse gases (GHGs) that contribute to global climate change. The energy currently supplied to ships by HFO/MGO/MDO can be replaced in the future by energy stored in batteries or by energy from synthetic fuels such as liquid hydrogen or ammonia that do not generate GES emissions. In addition, diesel or marine methane can also be synthetically produced by capturing and regenerating H2 and CO2 and used as a replacement for fossil HFO/MGO/MDO. Taking into account the technical characteristics, including the conversion inefficiencies of each type of technology, the implications on primary energy production will be different, that is, an increase in efficiency is recorded with each type.

The paper presents an autonomous datalogger supplied by a flexible solar panel with a Lithium-Ion battery and a supercapacitor as energy storage. Relevant issues in design, implementation and testing are presented, as well as some measurements performed during summer days.

The paper focuses on analysis of inductive and optical displacement sensors and their use in industrial applications. Differential inductive displacement sensors, usually in the form of linear variable differential transformer LVDT, are widely used in hydraulic applications because they have excellent accuracy, robust construction and are able to measure large displacements (in hundreds of millimeters range). However, they are large, heavy and offer slow measurements. For fast measurements, in millisecond range, optical sensors like time-of-flight ranging sensor could be a better choice, and present paper investigates their performances and compares them in this regard with inductive sensors.

Remote sensing image scene classification is a contentious research area, particularly in difficult-to-classify regions. The Danube delta is a constantly changing and difficult to categorize region. Machine learning methods have recently been used for scene classification because of their beneficial results. For many remote sensing applications, co-registration of Multi Spectral Images (MS) and Synthetic Aperture Radar (SAR) data is crucial. This paper focuses on both supervised and unsupervised novel machine learning methods, such as t-SNE, k-means, and SVM, applied to co-registered Sentinel-1 and Sentinel-2 data of the Danube delta. The outcome demonstrates that Sentinel-1 vertical-vertical (VV) is a better band for data training since it exhibits more details, and the learned SVM classifier using t-SNE can be applied to other days with a respectable level of accuracy.

Thin films of the (Ga_xIn_1-x)₂O₃ compound have been prepared on Si substrates by the aerosol deposition method with variation of the Ga concentration (x) from 0 to 0.95. Indium chloride (InCl₃) and gallium nitrate (Ga(NO₃)₃) were used as precursors. The morphology, chemical composition, and crystal structure of the obtained films have been investigated by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analysis. The vibration modes have been deduced from Raman spectroscopy measurements to gain additional data concerning the crystallographic structure of phases constituting the deposited films. The optical absorption spectra were analyzed at room temperature in order to determine the bandgap as a function of the x-value in thin films. The photoresponse of films was investigated under the radiation with wavelength from the ultraviolet (UV), visible, and infrared (IR) spectral intervals. The performed investigations demonstrated the polycrystalline nature of films, consisting of high quality nanocrystals, ensuring a gradual increasing of the bandgap from 3.50 eV to 4.85 eV with increasing the x-value from 0 to 0.95, and a predominant photoresponse in the UV spectral range.

Here, we report on a study of the magnetoresistance (MR) of small-diameter individual Bi and Bi_0.83Sb_0.17 nanowires down to 1.5 K and for magnetic fields up to 14 T. Glass-coated single-crystal microwires were fabricated by the Ulitovsky method. The thin nanowires samples, d<100 nm, that were investigated displayed pronounced h/e and h/2e resistance oscillations (Aharonov-Bohm (AB) oscillations) as a function of magnetic flux. The observation of these periods is consistent with considering Bi and Bi-Sb nanowires as a tube of surface states. The most intriguing is the presence of MR oscillations equidistant in the magnetic field when the magnetic field is perpendicular to the nanowires axis, when the magnetic flux through the nanowire cross section is zero. In 45-nm Bi nanowires, the self-organization of helical edge states of Bi bilayers led to the formation of series-connected stacks of bilayers, each of which had a closed conducting loop in a transverse magnetic field which results in the appearance of AB oscillations. Apparently, a similar interpretation can be applied to Bi_0.83Sb_0.17 nanowires.

Harmonics generation in plasma by high-power pulsed lasers is an important task for plasma diagnosis. This is because of the strong relationship between the plasma characteristics and the properties of the harmonics radiation. Here we analyze the spatial and temporal properties of third harmonic (TH) radiation generated by focusing ns and fs laser pulses in air at intensities of the order of tens of TW/cm2. The air is considered a non-dispersive non-linear (NL) medium due to the low density ofN2 ions in the breakdown plasma produced under the laser pulses. We address the influence of the pump laser intensity on the properties of TH radiation. We find theoretically and experimentally that the intensity of TH radiation at the output of the NL medium increases linearly with third power of the pump peak intensity, both for ns and fs laser pulses. In case of fs pulses, we demonstrate that TH pulse duration decreases with pump intensity, in correlation to the air breakdown plasma properties. In case of ns laser pulses, we demonstrate that the TH beam diameter is two times smaller than the fundamental’s. The theoretical results on the dependence of the TH signal to the driving peak intensity are supported by experimental data. We further analyze the influence of the gamma radiation on the several commercially optical fibers that are usually employed in the laser-target interaction area. The radiation effects such as photo-darkening induced in optical fibers can severely decrease the performance of optical transmission. We investigated the change of optical transmission induced by gamma-ray radiation. Multimode optical fibers, with a core diameter of 200 μm (usable in UV, ultra-highvacuum and high temperatures conditions), were investigated in order to evaluate their possible use for diagnosis of plasmas produced by high power lasers. The optical properties were studied by analyzing the transmitted spectra of the fibers before and after irradiation, demonstrating a decrease of the measured spectrum of the optical fiber output when increasing gamma dose to 16 kGy. The results are important from both fundamental and practical points of view, providing an efficient tool for prediction of the non-linear optical phenomena in laser produced plasmas and for non-contact diagnosis of the harmonics-generating plasmas.

We have reported the experimental observation size effects and surface state on semiconductor Bi_1-xSb_x wires with different diameters and alloy composition. The studied glass-insulated single-crystal wires of Bi_1–xSb_x semiconductor alloys were prepared by liquid-phase casting in accordance with the Ulitovsky method. The wires of all the studied compositions and diameters had the same orientation as that in the pure bismuth wires (1011 along the wire axis). A comprehensive study of the temperature dependences of resistance at T = 1.5–300 K, longitudinal and transverse magnetoresistance and their angular dependences, and SdH oscillations in magnetic fields up to 14 T as a function of wire diameter has been conducted. It has been found that the manifestation of the quantum size effect in TI wires based on semiconductor Bi_1–xSb_x alloys near the gapless state leads to an increase in the energy gap by a factor of 4 at wire diameters of 180 nm, and the SdH oscillation periods at H//C₁, C₂, and C₃ quantitatively differ from values for bulk samples of the respective composition. The longitudinal magnetoresistance (Н//I) has a maximum that linearly depends on wire diameter d, H_max = p_F c /ed. In the Bi–8at%Sb and Bi–17at%Sb, the Fermi momentum component p_F perpendicular to the magnetic induction vector H exceeds the values for pure Bi by a factor of 2 and 5, respectively. The results are discussed in terms of the manifestation of the quantum size effect and the specific features of TIs in low-dimensional structures that require new approaches and applications.

This paper expands on the concept of quality and links it with the concept of fractal by means of Theory of secrecy, taking into account that the additive model of quality has virtually the same mathematical expression as one of the models presented by C. E. Shannon in his work regarding Theory of secrecy. Based on the theory of Shannon, a possible enciphering model is constructed. This model generated to implement the theory of Shannon is explained for the general case and then based on this, a particular model is presented. This particular model is then approached using a set of C++ subroutines which implement the subject model. This paper shows that, if quality evolution is properly analyzed, quality could be to a certain extent, also predicted. Furthermore, this prediction of quality can be used in a more general way, namely to predict evolution in a structure exhibiting more features or dimensions, such as, for example, a fractal structure such as presented in [3], [4] and [5]. Taking into account that the very same weighted addition method or model is used for both, to generate the encryption in a secrecy system, but also to calculate the quality value of a product or service exhibiting a certain number of quality features, one can link these two in an appropriate way, such as will be presented in this paper. Thus, quality evolution properly analyzed, could lead also to a prediction to a certain extent, of the respective quality. This paper extends the work of C. E. Shannon and is based on his papers: Communication Theory of Secrecy Systems and A Mathematical Theory of Communication The theory presented and developed by Shannon has been successfully used and has been proven during the last seventy years since its discovery. This theory is practically used in this paper by means of particular encryption/ decryption C++ algorithms, which show how to put this theory into practice in order to make predictions about quality or other abstract or material natural systems. These C++ subroutines may very well be extended for a more general, complicated case of encryption, similar to the enciphering case presented in this paper. The algorithms presented in this paper show how an encryption model should be approached using a certain software. This paper also expands previous results obtained by author in [3], [4] and [5].

This paper constructs a model of communication with Nature, but also expands on the concept of fractal and thus continues the work developed in another paper presented within the same Conference. Main idea of this paper is that, if and only if a Golden Number or a Golden Function or Rule which governs some of the natural processes does really exist and somehow Nature would show availability to communicate with us, the respective rule may be much more complicated than originally thought, in order to more extensively explain Nature. Such a complicated rule may then be based not only on a single number or function, but on a procedure or rule containing a set of various different functions. This paper presents an algorithmic model to search for a certain specific procedure which could be fitted to natural or even abstract processes, in order to predict their evolution, based on a structure with multiple recursive rules. This structure presented in paper attempts to anticipate and guess the moves of Nature and is actually a generalization of the concept of fractal. Since ages, man was fascinated by the existence of a Golden Number or Golden Section which could explain all shapes, phenomena and happenings in Nature. Unfortunately, experience and interaction with nature has shown that this originally thought magic number, occurs much rarely in Nature than initially believed and his occurrence has been considerably overestimated and many time forced, such as will be also presented in this paper. In search for a generally valid existing rule, this paper attempts, based on a special model which will be explained and applied by means of this paper, to extend and to expand the concept of fractal. Consequently, an algorithm is generated in Matlab or Octave software which actually implements the above mentioned model. The present paper also expands previous results obtained by author in [1], [2], [3] and [4]. Going out from the hypothesis that a general applicable rule which explains much of processes in a certain domain of nature, material or abstract, does exist, this paper aims to identify and construct possible solutions for this presented problem. At first, the term of communication with nature is presented and what the reader should understand when referring to communication with Nature. According to this definition, Nature clearly communicates with us by means of fractals and fractal shapes, which actually are the most common and the best known and understood forms of this type of communication, so far. But it would be inappropriate and preposterous to claim that this could be the only way Nature communicates. The fractals could represent only a small fraction of this communication and they may be only the top of the iceberg in the communication with Nature. Going out from the definition of communication with Nature, a solution to a possible extension of the entire concept of communication with nature is given by means of a special theory of encrypted communication, based on an original model which combines certain types of functions. A new original concept and tool, namely the concept of communication function matrix (CSN Matrix), is also defined and introduced in this paper, with the purpose to generate the proposed communication model. This tool, the CSN Matrix, is created to identify communication with Nature, and will represent the main tool in the proposed communication model with Nature.

The control of biological wastewater treatment can still be considered an open problem in the literature due to the difficulty of meeting environmental standards. The main objective of the biological treatment of wastewater is the removal of non-sedimentable organic solids, the stabilization of organic matter in sludge and the reduction of nutrients based on nitrogen and phosphorus. Knowing the complex structure of the biological purification process, the success of the command and control operation requires the division of the phenomena that occur according to the main effects and their nature. In this paper, an artificial neural network is used to optimize the biological purification process. The chosen network is feedforward and was driven by the backpropagation method using the supervised learning mechanism. The neuronal optimizer works at a higher hierarchical level than automatic regulation.

This paper presents a detailed experimental study on operability of a target tracking system based on YOLOv4 for target detection. This work aimed to determine multi-dimensional regions where the two parameters of YOLOv4 algorithm, detection threshold and IOU threshold, allow obtaining the maximum of performance from the detection algorithm, represented by 100% detection for the overall possible detected targets. Low values of these parameters allow more detections, but also increased the number of misclassifications, counted as wrong detections. On contrast, high values of these parameters increase the detection accuracy, but on the cost of total number of detected targets. Considering that each of these parameters can have at least 9 values, 0.1 to 0.9, resulting in 81 combinations, the identification of local and global maxima and minima and of an operational zone, in which the system performance is stable, could be considered as priorities on context of optimal use of the overall target tracking system. Given the high diversity of graphics representation for the system performance in respect with the variance of these two parameters, each of them influencing in an inter-dependent mode the overall performance of the system, the authors propose that the results of each experimental complex scenario to be consolidated in 3D graph, named decision space, one for each environmental context, in which each point is the result of system efficiency reported to a specific pair of values of the mentioned algorithm parameters. These decision spaces present in aggregated form the performance obtained in a target tracking scenario, related on a specific environment, but considered all possible parameter values. The results can be used as a method of pre calibrating the target tracking system prior of effectively using it for its main purpose.

The quality of insulating materials is a very important aspect of the design of buildings and the assessment of the influence of the external environment to ensure the lowest possible thermal conductivity and the highest possible compression and flexural strengths. The purpose of this article is to analyze two sets of aerogel compositions in two types of plasters (own composition and commercial composition) to obtain new plasters with aerogel, used for buildings insulations. For the laboratory experiments, to measure the thermal conductivities of obtained plasters it was used a Heat Transfer Service Unit for Building and Insulating Materials, type H111N, and for determination of the mechanical strengths it was used a Universal Testing Machine Hegewald & Peschke INSPECT SOLO. The Wilcoxon Signed-Rank Test was used to determine the most effective composition in terms of isolation.

Strongly coupled, highly dissipative arrays of Josephson junctions are characterized by presence of two branches for the currents greater then the critical one in their IV characteristic. Additional branch, called traveling wave branch is characterized by low voltage, generation of charge density waves in the stack. Traveling wave branch appears on the IV characteristic only if coupling and dissipation parameters have the values above their thresholds. In this work we focused on the study of charge density waves behavior in the specified type of Josephson junction arrays in order to explain the stability of the traveling wave branch. Were performed numerical simulations using Capacity Coupled Josephson Junctions with Diffusion Current (CCJJ+DC) model which gives good agreement with the experimental results and were obtained IV-characteristics and charge density temporal evolution profiles for different currents corresponding to traveling wave branch. Was shown that the form of charge density waves changes with the increase of current. Moreover was studied spectral structure of charge density waves and dependence of Lissajous correlations between charge accumulated on the neighbor superconducting layers on the current. thought the stack.

The assignment of work uniformly, across an available group of processors, represent an important problem in parallel computing. The efficiency of the workload balancing is obtained by a proper partitioning strategy, which is a challenging task. Partitioning is an important concept connected to various other problems in modern computing field and also an extensively-studied problem in graph-based analysis. The computational graph in parallel computing model defines units of computations (or tasks) as nodes and data dependencies (or communications) between units as edges. A k-way graph balanced partitioning algorithm is proposed, with the objectives of partitioning the graph nodes into k equal sized disjoint components, while minimizing the number of edges crossing between components. This edge partition model is suggestive for mapping computations to processors, while reducing the interprocessors communications. The partitioning problem turned out to be a NP-hard problem of combinatorial optimization, so we proposed a Genetic Algorithm with fuzzy adaptation of parameters for determining optimal partitions within a reasonable amount of time. The performance of the partitions was assessed based on two performance metrics, namely density and conductance. Based on randomly generated application workflows, experiments with different values of k were performed to demonstrate computational capabilities of the proposed algorithm.

The optimization of production systems processes is driven by the international competition and the manufacturing technological advances. In recent years, more attention has been given to assess the potential advantages of using the innovative technology to elaborate different scheduling solution procedures in order to balance production efficiency and obtain high levels of productivity. Computerized scheduling systems for process operations can be used to achieve high system utilization: to identify and eliminate weaknesses and avoid unscheduled failures and resource waste. In this study, we extend the general scheduling framework to model a specific machine-scheduling problem that characterizes real industrial frameworks with more complex functional demands: precedence-constrained tasks, individual processing times of operations on different machines and communication cost between tasks that are not assigned to the same machine. The specificity of this problem generates an increased complexity and needs higher computational effort compared to a classical task-scheduling problem. The problem is modeled as a Mixed Integer-Linear Programming (MILP) formulation and is solved using a Particle Swarm Optimization approach - a heuristic population-based global optimization method that performs well in difficult multi-objective optimization problems arising in computer science and engineering. The proposed workflow task scheduling and allocation algorithm was tested on several randomly generated test instances. Experiments have shown valid scheduling results: minimum schedule lengths were obtained, while task-precedence constraints are fulfilled. We also noticed good computational experience even when problem size was increased.

In the context of music production “Listening” is the main tool for judging the aesthetic quality of audio recordings. However, for our ears to correctly judge artistic and technical quality, they must “work” in controlled conditions. Overall, this paper puts emphasis on the main methods of simulating acoustical parameters for a given room, acquiring real-world data by measuring the room in question, underlining issues, possible solutions, and establishing the accuracy of the methods used. This research aims to design and develop a listening room for proper subjective assessment of release ready program materials, with the principal focus on further development of intelligent music production tools.

Hybrid modeling is an intelligent knowledge acquiring strategy that becomes very important in the nowadays complex conditions and severe constraints. Hybrid modeling requires several types of 'building blocks' or basic components: standalone efficient solvers, interfaces between the data sources, mathematical libraries etc. When a new model must be conceived, new components must be swiftly developed. The short access time to large amount of data is a basic requirement which was a constant concern of ours along the time. Our latest solution is based on class templates used to dynamically allocate the memory by creating circular doubly linked lists and other upper level data structures. Facilities of the C++ Standard Template Library were also studied. We may consider the template classes as ‘stem cells’ in the software development process. Several cycles consisting of thorough analysis plus development of software demonstrators meant to clarify practical aspects led to a firm foundation and a strategy to conceive and rapidly develop effective software components for hybrid models, regardless the field of science.

The paper presents some aspects regarding the conception and construction of an experimental test rig used for studies concerning friction phenomenon of threads immersed in oil, maintained in a state of motion with constant velocity. The structure of the experimental test rig, testing methodology, experimental results and the applicability of the experimental set-up were detailed. To validate the experimental equipment and method, the obtained values were correlated with those obtained analytically. A good correlation was found, which attests the applicability of the test rig and method.

The paper purpose is to investigate the influence of some of the machining input factors and conditions on the surface texture and roughness parameters. The machining tests were carried out on a homebuilt (DIY) CNC router with a one teeth carbide flat end mills. The router movements were calibrated in order to assure three decimals precision. The spindle speed is controlled by a frequency converter that allows setting the speed ranging from 0 to 20000 rpm. Rectangular pockets were milled considering cutting across and along the grain and at a 45-degree angle. Different cutting path strategies were generated using a specialized CAM software. A Taguchi DOE method was considered and a confocal microscope type CWM 100 produced by Mahr was used to analyze the surface texture and roughness parameters.

For almost three decades, InGaN (indium gallium nitride) quantum well (QW) lasers have received a lot of interest from the scientific research community. Recently, this material system has become probably the most intensively studied among all the material systems used for quantum well lasers. We simulated the characteristics of an In_0.02Ga_0.98N QW laser at a wavelength of 462 nm, particularly the carrier concentration distribution, the potential distribution, the energy band diagram, the wave intensity profile, the I-V and L-I characteristics, the background absorption, the radiative, Auger, Shockley-Read-Hall (SRH) and stimulated recombination, threshold current density, slope efficiency and external differential quantum efficiency, to gain an almost exhaustive general view of the performance characteristics of this structure, constituting in a more useful reference for applications than previous incomplete data gathered for this structure.

In the last two decades, quantum well (QW) lasers have been used for a wide range of applications at wavelengths spanning on a very large domain and based on various material systems. A very interesting such material system is InGaAsN with dilute-nitride. We performed a comparison, by means of LASTIP simulations, between several structures of QW lasers based on this alloy, with the purpose of finding the laser structure which constitutes the best choice for being applied in practical situations with the most convenient performance parameters required in every case.

This work is derived from our recent studies about the new approach for interconnecting the electronic components without the use of solder alloys. The concept is generally called Solderless Assembly for Electronics Technology (SAFE). We will present the results of thermal analysis and measurements of electronic modules that were realized in SAFE technology. In a SAFE module, the natural convection from the top of a component is blocked by the resin, as a result of molding process. The interconnection of components and simultaneously the conductive tracks are realized using the same printed conductive paste. Having interconnections with higher resistance, supplemental to the heat generation in electronic components, in our case resistors and LEDs, will be added to the supplemental dissipation caused by the current flow.

Recent advancements in the field of adaptive filters based on the least-squares minimization criterion propose a stable and efficient recursive least-squares (RLS) algorithm with attractive numerical properties and performance similar to the classical RLS methods. The combination between the RLS and the dichotomous coordinate descent (DCD) iterations (i.e., the RLS-DCD) offers an attractive option for practical applications with low requirements in terms of chip area. This paper employs a data-reuse methodology to further improve the tracking speed of the RLS-DCD algorithm. Furthermore, a regularization principle is used to develop its robustness features in low signal-to-noise working conditions.

Although the marіne dіesel engіne market іs domіnated by slow-coupled two-stroke engіnes wіth a dіrect couplіng system and a crossover system or four-stroke engіnes wіth medіum or hіgh speeds, equіpped wіth a reversіng system, there іs a hybrіd varіant that has always been used by the market іn Japan and East Asіa, especіally by coastal or fіshіng operators. These are four-stroke slow engіnes. These types of engіnes are a specіalty specіfіc to the Japanese profіle іndustry, beіng characterіzed by a sіmple and robust constructіon and faіrly long pіston strokes. The rated speeds of these motors do not exceed 200 rpm, whіch allows dіrect couplіng to the propeller, elіmіnatіng the need for a reductіon system. Compared to equіvalent engіnes on the US or EU market, where medіum or hіgh speed four-stroke engіnes are preferred, the Japanese model has 6-cylіnder іn-lіne confіguratіons, and the pіston dіameters of these engіnes may vary dependіng on the need for on market. For example, Akasaka Dіesel buіlt engіnes of the same type usіng pіston dіameters rangіng from 220 mm to 510 mm, all wіth іn-lіne 6-cylіnder confіguratіon.

Advanced concepts are applicable in practical activities when a certain level of technological development is reached. Accordingly, the reusability of some of the data encryption algorithms is feasible, because of the new concepts in cryptography and of the fast nowadays computers. Starting from a study dedicated to several ciphers, the paper presents a framework meant to integrate encryption methods, considering a multilayer encryption structure. The encryption methods were implemented as classes in order to identify their main features, to check their flexibility and to assess the opportunity to consider them in upper level approaches. The resulting software applications are parameterized and they consider several variants of a given cipher, for comparison reasons. Regarding the rotating grille encryption method, important aspects are presented regarding the creation of the grills. Several tests were run and an application which integrates the aforementioned classes is under development.

Semi-numerical analysis, cryptography, operations research, gaming, gambling and simulation models where is desirable an unpredictable result rely on random numbers. In order to produce long sequences of random numbers, several ideas may be used: physical sources of randomness, arithmetic operations, chaos theory, machine learning which uses physical sources of randomness, functions included in the libraries of the programming languages, hash functions. Regardless the method to produce pseudo-random numbers, the results of the random numbers generators (RNGs) must be tested in order to provide a high degree of randomness. The paper presents several methods to produce pseudo-random numbers and proposes a framework to test the degree of randomness using criteria originating from Monte Carlo methods and from NIST requirements. A software application was developed in C++ for testing files containing pseudo-random numbers. Its flexible structure allows the addition of new modules that implement new testing methods. The files containing sequences of pseudo-random numbers were generated using original applications developed in C++ GNU Multiple Precision, GNU Octave, Java, Python, PHP, JavaScript.

This paper deals with a notable absence of in the signal processing libraries of MATLAB/GNU Octave computer algebra systems (CAS): the Schmitt Trigger. As far as we are aware, MATLAB lacks an implementation of a Schmitt Trigger function. GNU Octave has a function built in signal package that implements a multi signal Schmitt trigger with levels, with inconstant results in our trials. We have implemented a compiled function in both suites, which solves the problem of the implementation and likewise the processing speed. Also, we are proposing a compiled implementation of this functionality compatible with both software suites. Compared to a script for loop implementation our function performs in average 10x faster in MATLAB and up to 2000x faster in GNU Octave, processing a 10^9 random vector in about less then 10s on a reference computer configuration.

In the marine environment the waves generated by the flow of the wind or by natural phenomena such as earthquakes inside the oceans need to be monitored and known before it takes effect. The sea waves are a complex phenomenon and their behavior is quite difficult to predict. The first step is to take accurate and low cost measurements of the sea surface oscillations. In this paper we model and analyze MEMS capacitive accelerometers using Comsol Multiphysics simulation software for monitoring low amplitude sea waves.

Size-tunable Ag nanoantennas for integrated metasurfaces (MTS) achieved by nanosphere lithography enable new photon management possibilities, facilitating a relaxation of the fundamental Snell’s law for light refraction. Thus, the refractive index for accumulation layer (ITO) of solar cell can be dynamic controlled by voltage on ITO/SiO₂ junction to focus and trap sunlight in the active area of the tandem cell. The OptiFDTD software allows us to design, analyze and test this modern photonic device with arbitrary model geometries and places no restriction on the material properties of the tandem cells for wave propagation, scattering, reflection, diffraction, polarization and nonlinear phenomena.

This study developed a one-dimensional model for a bipolar membrane unit used in desalination stacks with the finite– element method (FEM) based Comsol Multiphysics software. The numerical model took into account the stationary transport of K⁺, Cl^-, H⁺ and OH^- ions inside a desalination channel unit using Nernst – Planck – Poisson equations and the Onsager theory of the Second Wien Effect for water dissociation under externally applied electrical fields. Electrochemical behaviour for the unit cell model was validated through the experimental current-voltage curve of a bipolar membrane, as it was reported in the literature. Influence of the anion–exchange layer (AEL) and cation–exchange layer (CEL) thickness variation and fixed charge concentration ratio in CEL/AEL regions upon specific desalination performance parameters, like co–ion leakage current, water dissociation turn-on voltage and water dissociation resistance were investigated here. Evolution of K⁺, Cl^-, H⁺ and OH^- ion concentration through specific compartments on the unit cell (electrolyte, AEL, CEL) at different potential drops across the membrane helped to understand the contribution of specific ionic fluxes at the total current through the system.

This paper is a guide for selecting an IoT embedded platform depending on the required performance, in streaming scenarios: data is received via UART, is processed (e.g. IAXPY, GEMM, AES encryption) and then is sent back via the same data interface. Platforms: 8-bit AVR (ATMEGA328P of Arduino UNO), 16-bit TI (MSP430), 32-bit RP2040 (Pi Pico board), 32-bit LX6 (ESP8266 and ESP32), 32-bit TI (CC3200), 32-bit STM32.

On the internal combustion engines with spark ignition engines (SIE) in four-stroke equipped with multipoint injection system (without supercharging system) multiple research topics have been developed to obtain optimal operation. The structure of the atomized liquid fuel jet using injectors that have been extracted from internal combustion engines with spark ignition engines (SIE) equipped with multipoint injection system, is the main topic of this study. Fuel leakage through the nozzles of injection devices create fluid accumulations in the area and implicitly decrease the pressure in the high pressure installation (caused by the lack of tightness inside the injector), a phenomenon that delays the start of the engine.

The cold start and operation of the internal combustion engines develops vast research on the phenomenon of fuel atomization in the combustion chamber, both for a homogeneous mixture of the air in the injected fuel intake and for fulfilling a precise stochiometric ratio, necessary to burn complete and precise. Starting from this hypothesis, it is considered necessary to deepen the study of the process of atomization of the liquid fuel jet, developed in the multipoint injection systems. In order to achieve this desire it is necessary to carry out vast research in this segment.

The present paper proposes an experimental test rig and methodology for the optical evaluation of micro-contact parameters in the case of micro-indentation tests of elastic materials with rigid indenters. Micro-contacts between small steel punches, of various shapes (considered rigid) and the flat surface of a synthetic glass (considered elastic), were investigated experimentally. The dimensions of the micro-indentation imprints determined by aid of laser profilometry were compared to theoretical results yielded by theoretical models from literature, [1, 2, 4], and good agreement was found. In order to verify whether the contact took place in the elastic or plastic domain, the tested surface was rescanned after a longer period of time, and it was determined that no remnant imprint was left. This confirms that the test was conducted in the elastic domain.

As is well known, the solution of analytical elastic contact problems [1, 2] is limited to a small number of specific contacts. For this reason, various numerical approaches were proposed to solve contact problems. The use of conventional numerical solving methods is however limited by the large volume of computation due to the use of fine meshing of the assumed area of contact with an important number of nodes. Various methods are proposed in literature to reduce the computing time and power needed to solve contact problems. In order to highlight the dependence between micro-contact parameters and the mechanical properties of the materials in contact, the present paper proposes the numerical modeling of micro-contacts using the Conjugate Gradient and Fast Fourier Transform technique (CG + FFT), [3, 4], and its adaptation to the micro-contact range. Model validation is performed by comparing the obtained results with the classical Hertz model, for various contact body shapes. The obtained results show very good agreement between the numerical and analytical results, thus validating the proposed numerical model.

In the ultrarelativistic limit it is possible to greatly simplify the manifestly covariant equations of motion for an electron. As such, we can bypass the need for constantly synchronizing the phase of the incident laser field with the electron as it propagates through the periodic enhanced laser near-field. Therefore, using FDTD numeric simulations, realized in MEEP, we propagate the field through the microstructure configuration. After optimizing the near-field energy density by sweeping the parameter space we have compared our semi-analytic result with a fully numeric integration realized using the package DifferentialEquations.jl from the Julia programming language. Finally, once we have an adequate design, we fabricated the 3D microstructures using laser direct writing via TPP (two photon polymerization). The technological limits such as fabrication tolerances have been tested and optimisation steps have been established.

In the last five years, there has been a major change in approach from a conceptual point of view in terms of cybersecurity that needs to be ensured at the level of a complete industrial chain from the perspective of a Smart Factory. In this paper we proposed to develop a complete Product Lifecycle management (PLM) system in conditions of cybersecurity. We started from conclusive global examples and analyses regarding the (in)security of the flow of information within the PLM, such as the incidents of Foxconn, Siemens, Schneider Electric, Autodesk. Using the paradigm imposed by the efficiency of PLM processes, we have developed an intelligent scalable micro factory at the Maritime University of Constanta, within the PLM Center. In carrying out this approach, we have considered, beyond the generic vulnerability families, several specificities of the interconnection equipment and systems used in the PLM process. Product development is accompanied by many changes, such as changes in customer requirements, errors in design and planning, availability of resources, etc. Thus, the entire PLM process processes an enormous amount of data flow, and to be efficient in a PLM system, the product data must be dynamically shared, easily, accessible, and inherently secure. The classic approach to the concept of PLM does not consider cybersecurity problems, the principal design of the concept being prior to the emergence of global security problems, for this reason we want to present our approach to develop a PLM system in cyber security conditions.

Most objects masked by vegetation are not discoverable for standard, centimeter wavelength radars. Conversely, radar systems operating at wavelengths in the order of one meter provide a good penetration through vegetation. In this paper, we propose a novel electronic antenna switch for low-cost pulse radar systems, operating either in the VHF or in the UHF range. The switch provides both modulated pulses to be transmitted and a locally generated carrier for demodulating the received signals. The switch configuration was successfully tested, separately and as a part of a radar system.

This paper presents an experimental implementation of ground-based interferometric synthetic aperture radar based on the low cost USRP platform and a computer. The purpose of the proposed system is to measure small displacements of the monitored targets over a long time period. These types of measurements are particularly useful in the field of civil engineering and ecology. Common applications are landslide monitoring or bridge and building deformation analysis, as well as glacier movement monitoring. The system implements stepped-frequency radar operation with a maximum bandwidth of 1500 MHz (500 – 2000 MHz). As expected with all interferometric measurements, due to the cyclic nature of the phase shift, the displacement must be smaller than a certain fraction of the wavelength of operation; otherwise the result will be ambiguous. In our case the displacement must be smaller (in absolute value) than a quarter of the transmitted wavelength. Due to the fact that in a software-defined radio the frequency is user selectable in a very wide range, the system can be configured to adapt to the magnitude of the expected displacement.

This paper presents an experimental wireless sensor network for monitoring underwater acoustic noises. Each sensor node consists of a floating platform anchored in the location of interest, powered by solar panel and storing excess electricity in Li-Ion batteries for uninterrupted operation. The communication between the sensor nodes and the central node (gateway) will be made by a radio link operating with the LoRa standard on the frequency of 433 MHz, a link that allows minimizing consumption and maximizing the distance between the sensor nodes and the central node (several km). The network implements the star topology. The sensors continuously monitor the sounds in the underwater environment and are triggered to store 5s of noise and then send it over the radio link to the gateway where it is stored locally on a server or sent to the cloud, in a database for further processing. The trigger level is configurable. Sound acquisition can also be started on demand, remotely.

This paper describes a method that can be applied for reducing the effect of the common mode currents when measuring the radiation of a small meandered monopole antenna. Moreover, it will be shown that the radiation of these currents can be extracted from the total radiated field. In order to validate our method, we considered a two-antenna measuring system consisting of a meandered monopole antenna (the antenna under test) and a loop antenna (the probe antenna). The measurements were performed in an anechoic chamber.

This paper presents a fast encryption algorithm for speech signals using the Arnold 3D and the Tent Map chaotic transformations. Arnold 3D chaotic map is known for the property of simultaneously combining pixel scrambling with changing their value in the process of image encryption. The aim of the architecture was to obtain a simple, robust algorithm with short encryption and decryption times, as well as resistant to attacks. All these features make it suitable for real-time communication. The algorithm consists in segmenting the speech signal, then transforming this frame into a cubic three-dimensional structure of samples. The samples are inserted sequentially in vertical slices. Arnold 3D transformation is applied to this structure on horizontal slices, each slice having its own encryption key generated by a Tent Map transformation.

In this paper, we propose a THz antenna design based on a scaling method from a microwave antenna, a meander line dipole antenna resonating at 790 MHz, which was analyzed over a broad frequency band and it was determined that the best features are achieved at 6 GHz. The scaled meander line dipole antenna presents a maximum directivity of 2.33 dBi at 10 GHz. Determine the gain of the meander antenna by reflection on a conductive wall.

This paper demonstrates the fabrication of a smart sleeve, able to monitor the elbow flexion by means of the carrying angle. The setup of the system includes the use of a polymeric optical fiber (POF) sensor, i.e., a sensor based on a POF fiber, a light-emitting diode (LED) and a photodiode. This represents an element of novelty in medicine, where until now only mobile applications or costly devices have been used for obtaining the desired results. The purpose of our paper is to replace the classical goniometer, used by physicians, with an optical goniometer, much easier to use, that the patient can use at home, without being necessary to go to a clinic. Moreover, our proposed application is unique, as it also belongs to the domain of smart textile devices. The goniometer is embedded in a sleeve that the patient can wear anytime and anywhere, to find the carrying angle, a highly important parameter for sportsmen, who often fracture their arms during their activities. The information obtained from the measurements can offer the patient an evaluation of his health state or of his degree of recovery after a fracture or operation, without requiring a visit to a physiotherapist.

Complex-valued convolutional neural networks (CVCNN) have better performance than real-valued neural networks in the field of terahertz imaging. In this paper, a complex-valued neural network is innovatively applied to terahertz image classification task in a vector network analyzer (VNA) imaging system. The complex-valued CNN (CVCNN) processing framework for terahertz image classification is proposed. Terahertz image datasets are constructed using MINIST handwritten datasets and PSF which was measured from our transmission system. Compared to CNN, CVCNN has a better accuracy rate, and it is significantly less vulnerable to over-fitting. Phase information can be used well at the same time, which is impossible for the CNN. The method of training data generation is given, and some specific implementation details are given. the superiority of the method in this paper is verified by using simulated and measured data obtained from 200Ghz image system.

Head related transfer functions (HRTF) and their corresponding time domain impulse responses have a decisive role into sound localization for humans and, an individualized measured set can improve the localization accuracy and overall quality of a virtual sound placement system. The measurement proves to be difficult in absence of an anechoic chamber and the use of available measured HRTF might not be sufficient for custom setups. This paper describes a fast measurement system for head related impulse responses and the corresponding processing for extracting the HRTF for a listener in normal reverberant rooms. The impulse responses are measured using the exponential sine sweep method as the listener rotates relative to a sound source. The influence of the loudspeaker is measured separately and compensated with a Wiener filter. To simulate the anechoic conditions the head related impulse response is selected only from the direct soundwave part of the measured room impulse response provided that the experimental setup is calibrated appropriately.

An algorithm which restores pixels from blurred MM (mammography), RMN (resonance magnetic image), CT (Computer Tomography) and OCT (Optical Coherence Tomography) biomedical images is presented. Improvement of the image having static blur is performed using an image processing algorithm consisting of following filters: nimble, sharpening, homomorphic, coherence shock and region of interest. Then, the contrast and the intensity of the image are enhanced. Once the algorithm applies, the display image has square pixels well defined. This achievement allows better view of details which were previously blurred. Prove of concept is illustrate with a set of demonstrative biomedical images. Pictures are rendered as pairs images in which one is blurred and the other one is filtered.

We used enhanced darkfield microscopy (EDM) to record hyperspectral images (HSI) of attached cells from SW1353 chondrosarcoma cell line exposed to ionizing radiation (X-rays, protons). Our investigations are conducted to highlight the effects induced by the incident radiation onto cells characteristics, their structural and morphological changes, revealed by HSI images. The cell nucleus was segmented and analysed separately on their entire area or at the level of a single pixel. Global analysis of the whole nucleus area was performed to find geometrical parameters: area, perimeter, major axis, circularity, eccentricity, solidity. Statistical analysis was performed on distributions of intensity values separated on five spectral intervals. Local analysis, at single-pixel level or at regions of interest was performed in terms of spectral profile, separated on nucleus and cytoplasm. This study suggests that the nonirradiated cells have spectral profiles with multiple maxima, in contrast with the irradiated cells which display single-peak spectral profiles. Differences between irradiated and nonirradiated cells were observed in parameters like area, eccentricity, solidity, kurtosis, skewness at different spectral intervals.

At present, gallium nitride semiconductor components have gained a lot of ground compared to conventional semiconductor components. This was possible by providing increased performance compared to classic silicon-based components. Following research, this paper reports on the advantages of GaN transistors in electric vehicles over conventional transistors currently in use. As a conclusion of this work, by replacing the classic silicon-based components with gallium nitride, a much better efficiency is obtained in the systems encountered on electric vehicles.

This work proposed a non-calibrated free-space materials characterization by vector network analyzer (VNA) and spot focusing lens. Compared with traditional quasi-optical measurements, it has no use of high gain antennas. A smaller spot of terahertz wave at the focal point means that smaller samples can be characterized. In measurements, time-domain transformation of S21 is carried out. Locations of the maximum value correspond to the fastest transmission path. Time-domain gating is applied to isolate the source mismatch error and multi-path effect. After that, samples were placed at the focal point, and frequency domain results of sample signals were recorded and calculated. Phase ambiguity is solved by linear fitting and extrapolation. The method we proposed can extract electromagnetic parameters of materials with no limitations on frequency. Results have higher precision than those applied Gate-reflect-line calibration method, which is considered the most accurate one.

Nowadays, display panels use white LEDs backlight to provide thin and lightweight devices with high brightness. The spectrum of white LEDs has an important blue component with a peak wavelength around 450 to 470 nm. The term “blue light hazard” (BLH) refers to the photochemical damage of the retina in the range of 380–550 nm. Blue light retinal injury can result from viewing either an extremely bright light for a short duration or a less bright light for a longer duration. Our studies and measurements focused on usual display panels of desktop and laptop PCs, used many hours a day by the operators who are endangered by the cumulative effect of blue light exposure. The paper will present the results and recommendations in order to order to minimize the risk of blue light exposure.

Face detection has multiple applications including recognition, people identification and detection of facial expressions. With the current pandemic crisis and due to the measures imposed to prevent Covid-19 spreading, the wearing of a protection mask became mandatory. The object of interest of this paper is to detect the wearing of an approved mask face using Viola Jones algorithm, aggregate channel features (ACF) and mathematical morphology. COVID-19 virus spread through the air, so it is necessary that all the materials used for manufacturing of the face masks to filter properly the air, and only the approved face masks to be used in order to control the spread infection. The algorithm used for face detection is Viola Jones with notable success in real time face detection and real time impression speed in face detection. Identification of the approved face mask against Covid-19 virus is made with a trained ACF detector. Eye detection, necessary to check if the face mask is properly placed, is based on mathematical morphology operators. These operations used together are robust with high results on the image processing.

The Internet of Things (IoT) is a new technology that employs a variety of sensors and wireless communication protocols. People are leveraging IoT to make their lives easier by using innovative and intelligent equipment. This paper presents a new approach, developed in order to increase the reliability in the IoT using the Harris Hawks Optimization (HHO) algorithm in a big data environment. Reliability and availability in big data represents critical criteria for selecting the most suitable protocol. Also, in most scenarios, the sensors' battery cannot be replaced, so energy consumption is another important issue in such IoT system. This research provides an enhanced artificial intelligence approach, based on the HHO technique, to handle load balancing between the Cluster Heads (CH) in a big data environment. A proper load balancing between CHs is vital in sensor network communication since it reduces the energy consumption of the devices. The HHO algorithm selects the appropriate CH by using a hunting technique, that is divided into 2 categorizes, soft besiege and hard besiege. The hunting depends on the remaining energy of the rabbit; at first, rabbit energy is high, but, after a while, the energy of rabbit decreases, so the Harris Hawks attack to this animal in soft besiege. Using this technique, we have tried to balance the energy and reliability of the Internet of Things between CHs. This proposed method was simulated on Network Simulator 3 (NS3).

Network environment challenges on identifying and direction finder of the emission sources can be performed in several different ways, depending on the spectral inter-frequency and of the equipment used. The tests performed that are still under development will show that there are many different scenarios that may lead to large difficulties in indoor locating of the radio equipment that are registered in standard mobile networks. Therefore, in this paper, we intend to test different receivers from different mobile communication standards with respect to the possibility of identifying and localization and to see the advantages and disadvantages of each generation of standards with respect to this issue.

Since we are currently surrounded by IoT systems that communicate wirelessly with each other, it is extremely important to know how they work, how to communicate, and how to manage them so that we can use these systems to their full potential. In this paper we will analyze communication in 433 MHz and 2.4 GHz radio frequencies. 433 MHz frequency communication modules will be compared with 2.4 GHz frequency communication modules both in terms of technical performance and in terms of the electromagnetic radiation they produce.

In this paper we propose a practical approach on how an attacker, commonly named “Data interception” technology can sniff your data traffic when you browse the Internet over a Wireless Connection and use it in their favor in order to obtain a pattern of your preferences, steal your personal data and create your online profile, exploiting some of the most popular internet protocols, such as TCP/IP, HTTP, IMAP or other important protocols. Using a network adapter in active mode in Kali Linux, we managed to sniff the traffic sent and received through a target Access Point (AP), inspect the individual packets in WireShark and create a personal profile of the owner of each device connected, obtaining data about the online applications that they are using, such as WhatsApp, e-mail clients, or data about their identity.

This paper aims to resume the information on the various ways in which security can be achieved when it comes to accessing external resources from the outside through company devices or personal devices. When planning security policies, it is essential to start with the idea that anything outside is exposed to the risk of infection. We will analyze the Zero Trust model and other security concepts in order to use them for remote access. The model has been designed to adapt to the modern needs of the workforce and employers, including remote work in terms of maximum cyber security, minimizing the risk of resource exploitation (people, devices, applications or data). In order to make the transition to such a model, this paper will implement and test a solution for remote management of resources (applications, servers), which implements some of the principles of Zero Trust architectures, starting from the classic version SSH (Secure Shell) access. The solution involves accessing, securing and authorizing a secure virtual machine via SSH, and then securing access to production resources. The technical mechanism by which these operations are performed presupposes that after authentication on the buffer machine a user certificate is automatically requested which will be signed by a certification authority. This certificate contains the group to which the operator belongs so that, by presenting this certificate, it is allowed to authenticate, authorize and audit access to the resources that will be managed by the user in that session.

As 5/6G technologies are constantly evolving, radio links must be easily designed and analyzed. Focusing on budget and spur analyses for frequency domain concurrently with time domain simulation, the present paper presents a complete and new evaluation approach for radio frequency (RF) links in conformance with matching at the ports of the RF components blocks. Frequency and time domain simulations of RF links allow shorter design time and higher performances in a what-if approach. In the system simulation of the proposed radio link, the signal heritage stipulates if a signal corresponds to the carrier or is a source of intermodulation or distortion produced in the link considering the compression point and leakage from output to the input of power in various points through the link.

This paper analyzes the possibility of an attack on an ultrahigh frequency radio frequency identification (UHF RFID) access system and presents some practical results for the systems that are in the ISO 18000-6 standard: we analyze the security breach of an RFID based system, namely the attacks concentrated on the access barriers that have already been installed within an institution. The testing was conducted in normal conditions where no interference was present, then a jammer was introduced transmitting with different transmission power values. It will be identified the situation where the system becomes completely unfunctional, the communication between the RFID reader and the tag is interrupted, the reading of the access code being impossible to perform. This underscores once again the physical radio frequency vulnerability of RFID communication systems, in this case UHF RFID systems.

The purpose of this paper is to validate the existence of vulnerabilities in computer networks - wireless networks which have in their architecture Windows operating systems. In order to demonstrate the vulnerabilities that still exist in windows 10 and windows 11 operating systems, the NetBIOS Name Service, Link Local Multicast Name Resolution, multicast DNS and WPAD protocols will be exploited. By exploiting these protocols, users' access credentials to the systems can be obtained. At the same time, we will propose a series of solutions that will reduce the chances of exploiting these protocols, to increase the security level of the network. Another role of this paper is to show that the use of Wi-Fi networks for the purpose of conveying confidential data is still unsafe. It also highlights the fact that improper use of the operating system Windows can lead to obtaining access data to an attacker who does not need powerful resources. The WPA2 protocol will be exploited to gain access to network resources, to subsequently formulate a series of conclusions aimed at inhibiting or completely reducing these security issues.

Our world is in a continuous evolution from all points of view, therefore there are new needs for which support must be provided and for which a series of new techniques have been proposed. In the field of wireless communications, we can talk about non-orthogonal multiple access (NOMA) technique, which is included in the 5G standard, that can offer an increased quality of service (QoS) to end users irrespective of their position within the cell or distortion factors. This paper presents a new set of complex spreading codes that fall in the coverage area of the 5G NOMA-based technique scheme. The creation of the new, aforementioned, set of complex codes starts from Walsh- Hadamard orthogonal spreading codes. Their performance will be tested using Monte Carlo Matlab simulations for bit error rate (BER) versus signal-to-noise ratio (SNR). The performance of the system will be tested in different scenarios, where the number of antennas at the receiver, the length of the complex spreading codes and the number of active users vary.

In aviation, transportation is a direct connection between the fuel consumed by aircrafts and carbon dioxide emissions. A new solution for determination of the necessary aircraft fuel will lead to companies’ savings and environment protection. The proposed method considers the commercial passenger aviation. The software developed by International Civil Aviation (ICAO) use a methodology for simulation of necessary fuel and for computing carbon emissions. A part of this methodology uses fixed value for passenger’s weight determination. Not all passengers from a flight have the same weight and, thus, the proposed method could replace the fixed value. Based on mathematical morphology operators, the new algorithm will improve the accuracy of aircraft fuel consumption with significant results on environmental protection.

In this paper is investigated the performance of an uplink MIMO system when the multi-user shared access (MUSA) technique is applied. The complex spreading codes used in MUSA are created starting from the traditional PN codes that are used in the code division multiple access (CDMA) systems. We choose this approach to be sure that the obtained complex spreading codes have low correlation. The numerical results will help us conclude if our proposed method, to create complex spreading codes, is achieving the best performance when the modulated information is transmitted over a channel affected by Rayleigh fading, in an overloaded system. The results obtained by our method will be compared with the ones obtained when the complex spreading codes are created arbitrarily.