Highly Nonlinear Solitary Waves (HNSWs) are traditionally used in the field of nondestructive evaluation to inspect a material’s property without causing damage. The research in this paper proposes a new application for HNSWs: predicting changes in Intraocular Pressure (IOP) to ensure optimum treatment and prevent the progression of Glaucoma in an eye. The HNSWs used for assessment were collected from a Polydimethylsiloxane (PDMS) eye model and are initiated and stored with a solitary wave transducer. To collect a full range of HNSWs that represent the biological range of IOPs in humans, the PDMS eye model is pressurized from 12mmHg to 26mmHg with 1mmHg increments and waves are collected at each pressure point. Once a HNSW is collected, it is wirelessly transmitted to a server where it is fed into a convolutional neural network to predict the IOP. This is done by extracting relevant features from the HNSW with a Fast Fourier Transform and constructing a spectrogram which can be fed into the algorithm pixel by pixel. This methodology works due to the association of frequency content in the HNSW and changes of the stiffness in the material. In the case of high IOP, the increased pressure pushes against the artificial PDMS cornea and causes it to become stiffer with a higher Young’s modulus. We evaluated the ability of the algorithm to predict IOP based on the spectrogram.
In this paper, we present a mixed-technology micro-system for electronically manipulating and optically detecting virusscale
particles in fluids that is designed using 3D integrated circuit technology. During the 3D fabrication process, the
top-most chip tier is assembled upside down and the substrate material is removed. This places the polysilicon layer,
which is used to create geometries with the process' minimum feature size, in close proximity to a fluid channel etched
into the top of the stack. By taking advantage of these processing features inherent to "3D chip-stacking" technology,
we create electrode arrays that have a gap spacing of 270 nm. Using 3D CMOS technology also provides the ability to
densely integrate analog and digital control circuitry for the electrodes by using the additional levels of the chip stack.
We show simulations of the system with a physical model of a Kaposi's sarcoma-associated herpes virus, which has a
radius of approximately 125 nm, being dielectrophoretically arranged into striped patterns. We also discuss how these
striped patterns of trapped nanometer scale particles create an effective diffraction grating which can then be sensed with
macro-scale optical techniques.
We present an alternative signaling method for multi-channel fiber ribbon based optical links. The method is based on a hybrid of differential signaling and single-ended channels. Channels are grouped into code blocks of n-bits. Each code word transmitted in the block is restricted to conform to an n choose m rule. Electrical drivers steer current between m active VCSELS with no dummy loads. A virtual reference is synthesized from the received signals and used for differential discrimination. This signaling method approaches the signal-to-noise characteristics of fully differential signaling but can be implemented with significantly lower channel overhead, giving as much as a 33% reduction in fiber count and a 44% reduction in power. Further, code utilization rates on these links can be as low as 51%, leaving substantial code space available for ECC or channel management functions. In this paper, we describe the signaling method and present a prototype transceiver chip. The transceiver is implemented in 0.25um UTSi Silicon-on-Sapphire technology with flip-chip bonded VCSEL and photodetector arrays. The design demonstrates a pin-compatible alternative to the POP4-MSA transceiver standard with 125% greater data throughput and 25% better power efficiency.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.