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This PDF file contains the front matter associated with SPIE Proceedings Volume 11503, including the Title Page, Copyright information, and Table of Contents.
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We have studied infrared absorption near the bandgap energy in mid-wavelength (MWIR) III-V photon detectors built in the nBn configuration. The absorbing material is the InAs/InAsSb superlattice. We show that in a practical device near the infrared (IR) cutoff, the spectral response curve as a function of photon energy is proportional to the absorption coefficient, to a good approximation. Thus, in the near-gap range, the energy dependence of the device spectral response is a reliable proxy for the energy dependence of the absorption coefficient. We demonstrate this by means of an expansion of the Hovel equations in powers of the product of the absorption coefficient and hole diffusion length. One application of this result is that the point of maximum slope of the spectral response curve can be used to locate the true bandgap energy. This result also facilitates a study of absorption in the Urbach tail, which occurs at sub-gap energies. The temperature dependence of the Urbach steepness parameter was found to be consistent with the dominant phonon energy of InAs.
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Graphene-based photodetectors have attracted attention for realizing optoelectronic devices including photodetectors. We report a graphene field effect transistor on silicon for broadband light detection from the ultraviolet to near-infrared region, which is compatible with the silicon technology and does not need a complicated fabrication process. The photodetectors show an improved responsivity. Specifically, fabricated graphene photodetectors shows a photo-responsivity of ~980 A/W at room temperature. These results provide a promising for the development of graphene-based optoelectronic applications with the broadband photodetection from the ultraviolet to near-infrared region.
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Random telegraph signal (RTS) noise is ubiquitous in electronic and electro-optical devices, having been observed in MOSFETs and photodiode arrays. For imaging arrays, in particular, RTS noise (blinking pixels or "blinkers") deteriorates system performance through poor nonuniformity correction (NUC) stability and degrades image quality with blinking pixel behavior that can distract human operators and confuse computer vision algorithms. To date, there exists no universally accepted identification method or description of RTS noise in photodetectors, nor a conventional analysis approach to determine its origin. Current approaches typically focus on spectral properties (RTS noise is characterized by a Lorentzian power spectrum), which can be expensive to compute through Fourier methods, and analysis is usually performed on only a small sample of pixels. Here, we propose a method to identify and characterize blinkers by training a hidden Markov model (HMM) to extract the principal parameters governing blinking behavior, including the underlying state space, the state transition probabilities, and the distribution of state output levels. We find evidence to support classifying blinking behavior with HMM parameters; the variation of the model parameters with extrinsic variables, such as the temperature and applied bias, give some indication of the underlying physical mechanisms. Specifically, we find the timescale of the blink current is longer than typical electron{phonon, electron{electron, and electron{photon interactions, which leads to the suggestion that the blinking mechanism may be related to trap occupation dynamics.
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Previously, Ratliff et al. and Sakoglu et al. developed algebraic nonuniformity correction (NUC) algorithms (the latter developed a matrix-based version with regularization capabilities) which mitigate fixed-pattern nonuniformity (noise) that is notoriously present in infrared image sequences/videos, by utilizing global translational motion of the scene or the imaging camera system. Infrared imagery, like almost any other two-dimensional (2-D) imagery, have been traditionally sampled and acquired using a rectangular grid, therefore the developed NUC algorithms work on this traditional rectangular grid mitigating the most dominant, bias/offset portion of the nonuniformity. On the other hand, it is well-known that hexagonal sampling grid captures more information in sampled data/imagery when compared to traditional rectangular sampling, and a hexagonal addressing scheme for hexagonally-sampled imagery, namely array set addressing scheme, was recently developed by Rummelt et al. in order to be able to convert imagery between the two different coordinate systems and to perform various mathematical and image processing operations. In this work, we derive the bilinear interpolation equations between two image frames for hexagonally-sampled infrared imagery with bias/offset nonuniformity under the 2-D global motion of the scene or the camera, and apply the 2-D algebraic NUC algorithm to hexagonally-sampled imagery. We present a simulation of MWIR infrared imagery with hexagonally-sampled pixel array, with global motion of the scene and with bias/offset nonuniformity, and we test the efficiency of the NUC algorithm on the simulated infrared imagery (based on real MWIR infrared imagery) and compare the performance of the hexagonally-sampled pixel array imagery NUC results to those of the traditional rectangularly-sampled pixel array imagery.
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A diversified infrared technology base has been developed over the recent decades for various civilian and military sensing needs. The technology has been optimized to balance performance and affordability constraints for a variety of end-use goals. Simplistically, these goals might involve the detection and measurement of nearby, bright sources that fill even the largest angular fields-of-view of pixels in simple, low-magnification systems for which abundant signal makes possible infrared detection and measurement with less-sensitive, uncooled sensor arrays. At another extreme are ultra-cryogenically-cooled systems operating below thermoelectric cooler capabilities and which enable the detection and measurement of much fainter sources that underfill even the tiny angular pixel fields of view set by the diffraction limit of large, high magnification optical systems. Our emphasis is closer to the latter for the applications described here. As one example of the environmental monitoring capabilities made possible in the infrared, gas leak detection in transmission pipelines is vitally important for safe operation and for protecting the environment by accounting for and assessing the impact of leaks that adversely affect climate change. Gas leak detection in the infrared spectrum is facilitated by the distinctive spectral fingerprints of fundamental molecular vibrational modes which can be exploited for the detection of the gas. Sensitivity becomes paramount for many applications requiring faint signal detection, and large sensor array formats facilitate surveillance coverage. Many climate change assessments are expected to involve wide-area coverage of Earth scenes with revisit times sufficiently short to capture important transitory events. Shorter term monitoring of containment compliance requires detecting sufficiently small gas leak flows over broad expanses of the Earth’s surface with high detection sensitivities. In this paper we described supporting technologies in the areas of sensor arrays and optical sub-systems, with an emphasis on dispersive spectrometers. There are a plethora of applications involving the stewardship of a range of biological assets, both in the ocean and on land environments, as well as large-scale sensing of atmospheric properties, including concentrations of greenhouse gases.
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Pulse rate (PR) is an important physiological parameter and can offer an indication of physical exertion. As such, optical pulse rate monitors for fitness tracking have grown in popularity in recent years and have featured as a component of many activity trackers and smart watches. These devices typically measure pulse rate using photoplethysmography (PPG) which requires an arrangement of a light emitting diode (LED) and a photodiode. The LED will emit light onto the skin and a portion of the light spectrum will be absorbed depending on the blood volume, with the transmitted or reflected light being measured by the photodiode. By recording the changes in the blood volume PR can be determined. This work presents a PR monitoring glove where an IR LED and a photodiode necessary for PPG have been discretely integrated into the structure of a textile. This has been achieved by using electronic yarn (E-yarn) technology where small electronic chips are soldered onto fine wires, encapsulated within a resin cylinder, and covered in fibers to create a mechanically and chemically robust yarn that looks and feels like a normal textile. The yarn production process, and the integration of the yarns into a textile, will affect the light emitted/collected by the optical components and these affects need to be fully quantified and understood so that an optimal sensing device can be engineered. Building on earlier studies this work investigates important design consideration, such as the emission pattern of the LED embedded Eyarns, in order to create a PR monitoring glove.
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The respiration rate (RR) plays an important role in the determination of the human health condition. However, the presently used conventional RR techniques are contact-based processes that cause discomfort, skin damage, epidermal stripping, etc. They often pose problems for babies having delicate skin, making them vulnerable to skin infections. Also, the present day neonatal intensive care units are dark from the inside, which limits the use of optical technologies in the same. Infrared Thermography (IRT) is a safe and non-contact alternative, which overcomes these issues. This paper presents the application of passive IRT in monitoring the human RR. The breathing signals obtained are noisy and are filtered using the Butterworth filter. The “Ensemble of regression trees” computer vision algorithm is used to automate the tracking of nostrils in real-time, during object occlusion, and random head motion. The “Logistic regression classifier” is implemented to characterize the respiration rate of the volunteers as normal, abnormal, Bradypnea (slow breathing), or Tachypnea (fast breathing). The Validation accuracy, Training accuracy, and Testing accuracy of the classifier are obtained as 97.5%, 98%, and 95%, respectively. The Sensitivity, Specificity, Precision, G-mean, and F-measure are also computed. Further, the Standard deviation of the classier is obtained as 0.02.
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GaSb-based materials can be used to produce high performance photonic devices operating in the technologically important mid-infrared spectral range. Direct epitaxial growth of GaSb on silicon (Si) is an attractive method to reduce manufacturing costs and opens the possibility of new applications, such as lab-on-a-chip MIR photonic integrated circuits and monolithic integration of focal plane arrays (FPAs) with Si readout integrated circuits (ROICs). However, fundamental material dissimilarities, such as the large lattice mismatch, polar-nonpolar character of the III-V/Si interface and differences in thermal expansion coefficients lead to the formation of threading dislocations and antiphase domains, which effect the device performance. This work reports on the molecular beam epitaxial growth of high quality GaSb-based materials and devices onto Si. This was achieved using a novel growth procedure consisting of an efficient AlSb interfacial misfit array, a two-step GaSb growth temperature procedure and a series of dislocation filter superlattices, resulting in a low defect density, anti-phase domain free GaSb buffer layer on Si. A nBn barrier photodetector based on a type-II InAs/InAsSb superlattice was grown on top of the buffer layer. The device exhibited an extended 50 % cut-off wavelength at 5.40 μm at 200 K which moved to 5.9 μm at 300 K. A specific detectivity of 1.5 x1010 Jones was measured, corresponding in an external quantum efficiency of 25.6 % at 200 K.
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Infrared (IR) technology has been widely used in biomedical imaging, non-destructive inspection, environmental monitoring and optical communication. The important mid-far-IR photodetectors are mainly limited to compound semiconductors that normally requires intricate crystal growth process and operation at cryogenic cooling, which results in bulky and expensive system. The emergence of two-dimensional (2D) transition metal dicharcogenides (TMDCs) semiconductors offers new opportunities for optoelectronic applications for their strong quantum confinement and the easiness in forming heterostructures enabled by the out-of-plane van der Waals bonding. The interlayer excitons formed in a TMDC heterostructure possess the inherent large exciton binding from their parent materials and the flexibility in exciton energy tuning. This offers opportunity to realize excitonic devices operable at room temperature at mid- to far-IR range, which are challenging for intraband exciton based 2D devices. This paper will introduce photodetection in mid-IR range by manipulating interlayer excitons generated between two specifically selected TMDCs with appropriate band alignment. The unique band structure in the heterostructure allows the absorption band to be tuned and extended to 20μm under a modest electric field, far beyond the cutoff wavelength of 2D black phosphorous or 2D black arsenic phosphorous. The ab initio simulation suggests the sizeable charge delocalization and accumulation at interface result in greatly enhanced oscillator strength of interlayer excitons and high responsivity of the photodetector. The results provide a promising platform for realizing robust tunable room temperature operating IR photodetectors.
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A novel and cost-effective technique to coat a fiber optic long period grating (LPG) sensor with silver paste to realize a reflection mode operation is presented here. LPGs have higher sensitivity compared to fiber Bragg grating (FBG) and are typically used as a transmission sensor. Recently, reflective LPG structures have been realized by coating the end of the LPG fiber with metal, but they have limitations as the fabrication process to coat the fiber with metal is either expensive or complex. In our work, we show a novel inexpensive technique to coat long lengths (60 cm or longer) of LPG with silver. The fabricated reflective LPG mimics the transmitted spectrum with improved selectivity. This simple coating method can be applied for other optical fiber sensors; such as metal embedded sensors for monitoring parameters at such critical locations not accessible to ordinary sensors.
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Detection of ultraviolet (UV) bands offers increased spatial resolution, small pixel sizes, and large format arrays, thus benefitting a variety of NASA, defense, and commercial applications. AlxGa1-xN semiconductor alloys, which have attracted much interest for detection in the UV spectral region, have been shown to enable high optical gains, high sensitivities with the potential for single-photon detection, and low dark current performance in ultraviolet avalanche photodiodes (UV-APDs). We are developing GaN/AlGaN UV-APDs with large pixel sizes that demonstrate consistent and uniform device performance and operation. These UV-APDs are fabricated through high quality metal organic chemical vapor deposition (MOCVD) growth on lattice-matched, low dislocation density GaN substrates with optimized material growth and doping parameters. The use of these low defect density substrates is a critical element to realizing highly sensitive UV-APDs and arrays with suppressed dark current and jitter under high electric fields. Optical gains of 5×106 and greater with enhanced quantum efficiencies over the 320-400 nm spectral range have been demonstrated, enabled by a strong avalanche multiplication process. We are additionally using device technology developed for high voltage GaN p-i-n rectifier devices to enable advanced Geiger-mode UVAPDs with single-photon counting capability. This technology provides extremely low leakage currents in the reverse bias range near avalanche breakdown, a necessary requirement for stable Geiger-mode operation. The variable-area GaN/AlGaN UV-APD detectors and arrays being developed enable advanced sensing performance over UV bands of interest with high resolution detection for NASA Earth Science applications.
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High performance detector technology is being developed for sensing over the mid-wave infrared (MWIR) band for NASA Earth Science, defense, and commercial applications. The graphene-based HgCdTe detector technology involves the integration of graphene with HgCdTe photodetectors that combines the best of both materials, and allows for higher MWIR (2-5 μm) detection performance compared with photodetectors using only HgCdTe material. The interfacial barriers between the HgCdTe-based absorber and the graphene act as a tunable rectifier that reduces the recombination of photogenerated carriers in the detector. The graphene layer also acts as high mobility channel that whisks away carriers before they recombine, further enhancing detection performance. This makes them much more practical and useful for MWIR sensing applications such as remote sensing and earth observation, e.g., in smaller satellite platforms (CubeSat) for measurement of thermal dynamics with better spatial resolution. The objective of this work is to demonstrate graphene-based HgCdTe room temperature MWIR detectors and arrays through modeling, material development, and device optimization. The primary driver for this technology development is the enablement of a scalable, low cost, low power, and small footprint infrared technology component that offers high performance, while opening doors for new earth observation measurement capabilities.
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Broadband antireflection (AR) optical coatings covering the ultraviolet (UV) to infrared (IR) spectral bands have many potential applications for various NASA systems. The performance of these systems is substantially limited by signal loss due to reflection off substrates and optical components. Tunable nanoengineered optical layers offer omnidirectional suppression of light reflection/scattering with increased optical transmission to enhance detector and system performance. Nanostructured AR coatings enable realization of optimal AR coatings with high laser damage thresholds and reliability in extreme low temperature environments and under launch conditions for various NASA applications. We are developing and advancing high-performance AR coatings on various substrates for spectral bands ranging from the UV to IR. The nanostructured AR coatings enhance the transmission of light through optical components and devices by significantly minimizing reflection losses, providing substantial improvements over conventional thin film AR coating technologies. The optical properties of the AR coatings have been measured and fine-tuned to achieve high levels of performance. In this paper, we review our latest work on high performance nanostructure-based AR coatings, including recent efforts in the development of the nanostructured AR coatings for UV band applications.
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Breast Tuberculosis (Tb) is a chronic granulomatous disease predominantly caused by Mycobacterium tuberculosis which is difficult to diagnose. The non-specific clinical and imaging characteristics and lack of familiarity of clinicians with this entity have led to increased rates of misdiagnosis as breast cancer or pyogenic breast abscess and make it a difficult diagnosis. Medical Infrared imaging is a non-invasive technology that records the temperature pattern of the skin by detecting emitted infrared radiation. This technology has been investigated as an aid in the detection and evaluation of several medical conditions such as psoriasis, burn wounds and breast cancer. In this work the thermal pattern of the breast of fourteen women with breast tuberculosis were obtained and compared to thermal patterns of healthy subjects and breast cancer patients. Results show that the average breast temperature in breast Tb patients is higher (34.0±0.7 °C) than the average temperature observed in healthy women (32.2±1.3 °C) but lower than the average temperature observed in breast cancer patients (35.8±1.6 °C). Also the thermal images of breast Tb did not present the characteristic vascularity patterns present in breast cancer thermal images. These results could be used for the implementation of digital infrared imaging as an adjunct method for differential diagnosis of breast pathologies.
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Due to their high availability and versatility, rolling bearings are a standard solution for mounting and support of rotating components. The service life of an entire rotating machine is often limited by the service life of rolling bearings. This can be shorter than expected if the rolling bearing is operated in harmful operating conditions, e.g. in the presence of slip. Slip means that there is a deviation between the theoretical angular velocity of the rolling element set and the actual angular velocity. In this context, slip is harmful if it leads to increased friction and thus heating of the bearing. The occurrence and properties of slip are not completely understood yet. Therefore, it is of interest to investigate a relationship between slip and heating of the rolling bearing in order to better understand damages of the rolling bearing. In this work, a method is presented in which, in addition to slip measurements with a high-speed camera, a thermal imaging camera is used to investigate the heating of the bearing during operation. Since the rotational movement and exposure time of the camera would cause motion blur, the thermal imaging camera is operated together with a derotator to optically eliminate the rotational movement. The investigations of the rolling bearing are carried out under different operating conditions (different loads and rotational speeds), which have an influence on the slip behavior of the bearing. Thus, the potential of this investigation method for deepening the understanding of heating and friction in rolling bearings is demonstrated.
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In this paper, an electromagnetic based human motion energy harvesting device is proposed. It consists of two similar Halbach arrays placed in front of each other to maximize the intensity of the magnetic field within which an attached three coils subsystem oscillates to generate a power supply of up to 19 mW. The device comprises a power electronics submodule which consists of three-phase full-wave bridge rectifier that uses Schottky diodes for AC-DC conversion, followed by a boost converter for DC-DC conversion. The sizing of both the permanent magnets arrays and the coil as well as the location where to place the system on the human body have been adequately set following extensive Finite Element Method (FEM) simulations, in addition of using Matlab and Pspice software tools. Particle Swarm Optimization (PSO) algorithm was used to determine the optimal sizing of the device corresponding to the lowest cost. A wireless accelerometer was placed at different locations of the body of an individual (e.g. lower and upper arms, elbow, ankle, and knee) moving on an indoor treadmill with different speeds to determine the best placement of the device corresponding to the highest power.
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Image-based industrial non-destructive testing techniques are commonly used for assessing material integrity. The cameras used for these tasks have lenses that can present form deviations, promoting anomaly creation on the acquired images. This problem also affects infrared cameras, but very often nothing is done to correct it, usually due to the cost of calibration tools for infrared wavelength. This paper describes then a manufacturing process based on the ablation of copper material with a pulsed laser of a cost-effective, infrared-reflective chessboard pattern for calibrating infrared cameras. Measurements of artificial defects in carbon fiber reinforced plastic plates with active lock-in thermography were performed and a comparison between the results with and without the corrections given by the calibration was done. The metrological benefits of applying the proposed calibration procedure have been evidenced by the reduction of the measurement bias and repeatability, which is important especially considering industrial non-destructive testing evaluations.
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Over the past decades, unmanned aerial vehicle (UAV) has been developing rapidly. The UAV can fly above most open area easily and understand the situation immediately. In this study, a restricted area that need to be controlled for 24 hours, the use of UAV with the thermal camera can be more efficient. This study applies thermal sensor fusion of an UAV for path planning, obstacle avoidance, and image processing for outdoor patrol. An UAV can follow a predefined path and search human target by thermal camera. Once the target is found, the UAV hovers above the object. Simultaneously, the location will be sent back to the control center. In the environment with known obstacles, the study uses the A* algorithm for path planning. For unknown obstacles, the UAV utilizes the depth camera and ultrasonic module to detect the obstacles. The FLIR DUO-R thermal camera is used to detect surroundings and checks whether if there is any desired target. About the image processing, the deep learning algorithm YOLOv3 is applied to identify human shape. Success detection rates of single object and multiple objects are both high accuracy.
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Based on the measured I-V curve of the Ag/n-Si Schottky photodetector, it can be verified that the Ag / n-Si Schottky photodetector can detect the NIR band. The responsivity of the photodetector without or with applied bias can be analyzed by the measured I-V curve. Furthermore, we eventually succeed in applying a pulse signal on the voltage source to resolve the thermal disturbance generated by the external voltage and also optimize the responsivity of the Ag/n-Si Schottky photodetector.
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We propose a gold -based nanostructured design for achieving enhanced absorption in ultrathin black phosphorus (BP) layers in the 3 – 5 micron wavelength range. We tune the design parameters to excite strongly localized radiation modes in layers of thicknesses ranging from 5 to 50 nm at 4 micron. In addition, we compute the absorption enhancement factor of these absorbers and compare it against the conventional 4n^2 limit. For a BP layer thickness of 5 nm, we are able to achieve an enhancement of around 150 which is significantly greater than the conventional value of 4n^2 equal to 64 for an isolated textured BP layer.
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Infrared (IR) photodetector is widespread applied to spectroscopy, biosensing, and image detection. Nowadays, most of IR photodetectors are prepared from compound semiconductors, for example, SiGe, HgCdTe, and InSb. However, most of them are formed through high energy consumption and high expense processes, such as chemical vapor deposition. Also, compound devices are not compatible with Si-based IC manufacturing and very expensive. Therefore, here, we used n-type Si (n-Si) wafers and Ag thin films to form a Schottky IR detector. The detection principle is using IR source to induce thermionic effect on Schottky diode and then the scattering of photoelectrons excited by IR and visible light, respectively, induces current difference. Regarding device preparation, at first, the native oxide on n-Si wafers was removed by buffer HF; then the 10-nm-thick Ag films and 100-nm-thick Ag grid anode were thermally deposited on the n-Si successively. Afterward, Al was thermally deposited on the opposite side of n-Si wafers to be a cathode. The electric property of devices was determined through current-to-time (I-T) measurement with an 80-mW green laser illuminating on the Ag side constantly. A 3.22-μm IR source was illuminated through Ag side but turned on/off for each 5 s. The electric bias is 0 V. Consequently, if no green laser exposing, current increased after IR turned on due to the pure thermionic effect and the responsivity is 1.8 mA/W. While the green laser illuminating constantly, current decreased after IR turned on, and the responsivity increased to -15.7 mA/W.
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Temperature changes in the body have been recognized as an indicator of illness for centuries, also localized temperature variations due to inflammatory or ischemic events are common in a great variety of diseases, these changes are due to changes in blood perfusion which are partly responsible, along with the metabolic heat generation of tissue, for the local temperature of tissue and organs. In the case of cancerous breast tumors there is an increase in vascularity due to angiogenesis and a higher metabolic rate compared to healthy tissue, which induces an increase in the local temperature of the tumor, this increase in temperature generates a small increase in skin temperature that can be detected with modern infrared imaging equipment. In this work the thermal characteristics, delta-T, vascularity and average temperature of the breast, of patients with cancerous and benign tumors were measured in order to determine differences in thermal signatures, which might help increase the usefulness of thermography as an adjunct tool in breast cancer screening. This thermal parameters were then correlated to the BIRADS and with histopathological findings. Results show some correlation between the thermal parameters and with malignancy of the tumors.
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The use of refractometers to investigate the nature of liquids is very common. Here it is shown that surface relief diffraction gratings can be used to measure the refractive index of liquids. Calibration plots showing the relation between first order intensity as a function of refractive index are shown. We also developed a microfluidic device behaving as a grating which is used as refractometer where a very small amount of liquid (microliters) is used.
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Wide band gap semiconductors such as TiO2, ZnO, and SnO2 etc., have attracted considerable research interest for their possible applications in emerging areas like Spintronics, photovoltaic and photocatalytic devices . Most important feature of doping is to achieve the room temperature ferromagnetism without altering the host semiconducting nature. SnO2 is one of the wide band gap semiconductor with rutile structure widely used in solar cells, transparent electrodes, gas sensors, LED, touch sensitive screens and transistors . Theoretical study was carried out in Mn doped rutile SnO2 using recently implemented Tran and Blaha's modified Becke-Johnson exchange potential model (TB-mBJ). The routine density functional theory calculations based on local density approximation (LDA) and generalized gradient approximation (GGA) underestimated the band gap of strongly correlated systems whereas TBmBJ exchange potential model was found to predict band structures and properties accurately.
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Modern devices based on the analysis of thermal images are used in the construction of technical systems and the analysis of processes occurring into objects. In the modern world, the analysis of information about temperature changes allows you to solve many problems, drive a car in poor visibility conditions (fog, smog, twilight or night), create security systems and control access to objects, analyze internal processes, including such as: chemical reactions; friction analysis; checking the operation of complex technical systems (bearings, electrical, lubrication, cooling); living organisms (analysis of processes tissue death); temperature audit of buildings; analysis of the operation of internal combustion engines; braking and friction analysis systems; other. The image formed by the thermal imager has a low resolution. In order to analyze complex processes, it is necessary to develop methods and algorithms for combining images into a single information field. The problem of stitching images is encountered in many areas of technology, but for IR it is the most difficult. The article proposes an approach that allows you to identify local features in IR images, which allows you to increase the accuracy of stitching pairs of images into a single composition. The proposed algorithm based on layer-by-layer image analysis. The analysis is based on the search for local features, followed by a change in the bitrate of the image and the study of stationary edges. An example of highlighting local features is shown on a set of test images captured by a thermal imaging camera. The scope of this approach is the task of combining images obtained only in the infrared range.
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