Volume Holographic Recording And Readout For 90-Deg Geometry, 2016 University of Dayton

#### Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva

*Monish R. Chatterjee*

When a prerecorded cross-beam hologram is reconstructed (so-called edge-lit readout) with a uniform plane wave and a point source, the resulting exact solutions reveal Bessel-function-type diffracted beam profiles, which are fundamentally modified under weak propagational diffraction. The case of a profiled beam readout with propagational diffraction may be analyzed using a transfer function approach based on 2-D Laplace transforms. In a second series of investigations, dynamic readout from a cross-beam volume hologram recorded with two orthogonal uniform plane waves is considered for various dependences of the refractive index modulation with intensity. Typically, refractive index profiles that are proportional to the ...

Plantmetabolomics.Org: Mass Spectrometry-Based Arabidopsis Metabolomics—Database And Tools Update, 2016 Iowa State University

#### Plantmetabolomics.Org: Mass Spectrometry-Based Arabidopsis Metabolomics—Database And Tools Update, Preeti Bais, Stephanie M. Moon-Quanbeck, Basil J. Nikolau, Julie A. Dickerson

*Basil Nikolau*

The PlantMetabolomics (PM) database (http://www.plantmetabolomics.org) contains comprehensive targeted and untargeted mass spectrum metabolomics data for Arabidopsis mutants across a variety of metabolomics platforms. The database allows users to generate hypotheses about the changes in metabolism for mutants with genes of unknown function. Version 2.0 of PlantMetabolomics.org currently contains data for 140 mutant lines along with the morphological data. A web-based data analysis wizard allows researchers to select preprocessing and data-mining procedures to discover differences between mutants. This community resource enables researchers to formulate models of the metabolic network of Arabidopsis and enhances the research community ...

Underwater Optical Wireless Audio Transceiver, 2016 California Polytechnic State University, San Luis Obispo

#### Underwater Optical Wireless Audio Transceiver, Angel Ayala

*Electrical Engineering*

Scuba diving carries risks that can endanger lives. Many of these risks are preventable. However, an underwater communication system can increase a diver’s safety. Along with providing safety, an underwater communication device can enhance the scuba diver’s enjoyment.

A low cost underwater optical wireless audio transceiver is designed. The project consists of the off-the-shelf parts that uses a microphone and speaker to transmit and receive sound. The project uses the concepts of visible light communications and pulse width modulation to transmit and receive sound. Although sound is commonly transmitted through ultrasound methods, visible light communications has several advantages ...

Prosense, 2016 California Polytechnic State University, San Luis Obispo

#### Prosense, Johnny Favazza Ii, Casey Glasgow, Matt Epperson

*Computer Engineering*

This project aims to gather advanced data sets from MEMS sensors and GPS and deliver it to the user, who can capitalize on the data. The once negligible half-degree difference of your board barreling down a wave can be recorded from a gyro and exploited for the perfect turn. The exact speed dreaded by longboarders where speed wobbles turn into a road rash can be analysed and consequently avoided. Ascertaining the summit of your flight using combined GPS sensors from the ski ramp allows for the correct timing of tricks. When it comes to pursuing excellence in professional sports, amateur ...

Design And Development Of A Low-Cost Radio For An Open Cubesat, 2016 Selected Works

#### Design And Development Of A Low-Cost Radio For An Open Cubesat, Michael Wegerson, Jeremy Straub, Ronald Marsh

*Jeremy Straub*

An Adaptable Fuzzy-Based Model For Predicting Link Quality In Robot Networks., 2016 University of Louisville

#### An Adaptable Fuzzy-Based Model For Predicting Link Quality In Robot Networks., Christopher J. Lowrance

*Electronic Theses and Dissertations*

It is often essential for robots to maintain wireless connectivity with other systems so that commands, sensor data, and other situational information can be exchanged. Unfortunately, maintaining sufficient connection quality between these systems can be problematic. Robot mobility, combined with the attenuation and rapid dynamics associated with radio wave propagation, can cause frequent link quality (LQ) issues such as degraded throughput, temporary disconnects, or even link failure. In order to proactively mitigate such problems, robots must possess the capability, at the application layer, to gauge the quality of their wireless connections. However, many of the existing approaches lack adaptability or ...

Role Of Diffusive, Photovoltaic, And Thermal Effects In Beam Fanning In Linbo3, 2016 University of Alabama, Huntsville

#### Role Of Diffusive, Photovoltaic, And Thermal Effects In Beam Fanning In Linbo3, Jaw-Jueh Liu, Partha P. Banerjee, Q. W. Song

*Partha Banerjee*

We analyze the steady-state (Gaussian) beam fanning in LiNbO3 from the nonlinearly coupled Kukhtarev equations by including both diffusive and photovoltaic effects and by adding the thermal effect in the calculation. There is good agreement between theory and experiment. The results show a symmetric beam-fanning pattern whose size depends on the beam waist and the power. Possible applications of our results in nondestructive testing of material parameters and optical limiting are discussed.

Self‐Refraction Of Nonlinear Capillary‐Gravity Waves, 2016 University of Dayton

#### Self‐Refraction Of Nonlinear Capillary‐Gravity Waves, Partha P. Banerjee, Adrianus Korpel, Karl E. Lonngren

*Partha Banerjee*

Self‐refraction effects have been observed during the propagation of deep‐water capillary‐gravity waves. The observations are shown to be in qualitative agreement with the theory of self‐focusing and defocusing in a cubically nonlinear medium in the presence of diffraction.

Single-Beam Holographic Tomography Creates Images In Three Dimensions, 2016 The Catholic University of America

#### Single-Beam Holographic Tomography Creates Images In Three Dimensions, George Nehmetallah, Partha P. Banerjee, Nickolai Kukhtarev

*Partha Banerjee*

In digital holography (DH), the interference between light scattered from an object and a reference wave is recorded using a CCD camera. DH has various advantages over analog holography: no film processing is needed, reconstruction is performed using numerical methods, and no further experimental setup is necessary. However, one of the disadvantages of DH is that current CCDs have a resolution of approximately 1,000 lines/mm, which is less than that of photographic film.

Subharmonic Generation By Resonant Three‐Wave Interaction Of Deep‐Water Capillary Waves, 2016 University of Dayton

#### Subharmonic Generation By Resonant Three‐Wave Interaction Of Deep‐Water Capillary Waves, Partha P. Banerjee, Adrianus Korpel

*Partha Banerjee*

Subharmonic generation has been observed during the propagation of deep‐water capillary waves. The observations are shown to be in agreement with the theory of degenerate resonant noncollinear three‐wave interaction in a nonlinear, dispersive medium.

Self-Enhancement Of Dynamic Gratings In Photogalvanic Crystals, 2016 Alabama A & M University

#### Self-Enhancement Of Dynamic Gratings In Photogalvanic Crystals, Nickolai Kukhtarev, Sergei F. Lyuksyutov, Preben Buchhave, Tatiana Kukhtareva, K. Sayano, Partha P. Banerjee

*Partha Banerjee*

We have developed a compact closed-form solution of the band transport model for high-contrast gratings in photogalvanic crystals. Our solution predicts the effect of the photoconductivity and the electric field grating enhancement due to the photogalvanic effect. We predict a pronounced dependence of the steady-state photogalvanic current on the contrast of the interference pattern and an increase of holographic storage time due to the enhancement of the photoconductivity grating contrast. In the high contrast limit and a large photogalvanic effect the refractive index grating will be shifted from the position of the intensity modulation pattern, contrary to the usually adopted ...

Simulation Of Two-Dimensional Nonlinear Envelope Pulse Dynamics By A Two-Step Spatiotemporal Angular Spectrum Method, 2016 University of Iowa

#### Simulation Of Two-Dimensional Nonlinear Envelope Pulse Dynamics By A Two-Step Spatiotemporal Angular Spectrum Method, H. K. Sim, Adrianus Korpel, Karl E. Lonngren, Partha P. Banerjee

*Partha Banerjee*

We present an extension of our previous nonlinear beam-simulation method to the propagation and interaction of pulse envelopes. The extra time dimension is applied in the context of a dispersive nonlinear medium that is described by a Klein–Gordon equation with an added cubically nonlinear, self-focusing term. Pulse propagation in this medium is modeled as the evolution of a spatiotemporal spectrum—i.e., the frequency-dependent angular spectrum of the pulse envelope—traversing a sequence of self-induced, thin, weak phase filters. Preliminary simulation experiments show agreement with known behavior in the absence of nonlinearity, confirm the existence of an (apparently unstable ...

Time Dynamics Of Self-Pumped Reflection Gratings In A Photorefractive Polymer, 2016 University of Dayton

#### Time Dynamics Of Self-Pumped Reflection Gratings In A Photorefractive Polymer, Partha P. Banerjee, S. H. Buller, C. M. Liebig, S. A. Basun, Gary Cook, Dean R. Evans, Pierre-Alexandre Blanche, J. Thomas, Cory W. Christenson, N. Peyghambarian

*Partha Banerjee*

The time dynamics of self-pumped reflection gratings in a commonly used photorefractive polymer PDCST:PVK:ECZ-BBP:C60 with no additional electron sources or traps is investigated. While holes are normally the mobile charges and responsible for grating formation, our experimental observations, analyzed using multi-exponential fitting curves, show evidence of electrons in addition to holes as charge carriers, particularly above an applied field of 40 V/μm.

The dependence of effective carrier mobilities on the applied electric field, deduced from experimental results, show stronger field dependence of electron mobility at high electric fields. At an applied field of 70 V/μm ...

Theoretical And Experimental Studies Of Propagation Of Beams Through A Finite Sample Of A Cubically Nonlinear Material, 2016 University of Dayton

#### Theoretical And Experimental Studies Of Propagation Of Beams Through A Finite Sample Of A Cubically Nonlinear Material, Partha P. Banerjee, Raj M. Misra, M. Maghraoui

*Partha Banerjee*

Propagation of an externally focused or defocused Gaussian beam in a cubically nonlinear material is studied analytically and experimentally. The theoretical analysis is applied to determine the sign and magnitude of *n*2 for a material by means of a single-beam experiment with a finite nonlinear sample within which propagational diffraction cannot be neglected. Experimental results for a solution of chlorophyll in ethanol are reported. Based on available theory, an average *n*2 can be defined for a nonlinearity of thermal origin, and this value is found to be in good agreement with experimental results. Finally, the theoretical analysis and ...

Volume Holographic Recording And Readout For 90-Deg Geometry, 2016 University of Dayton

#### Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva

*Partha Banerjee*

When a prerecorded cross-beam hologram is reconstructed (so-called edge-lit readout) with a uniform plane wave and a point source, the resulting exact solutions reveal Bessel-function-type diffracted beam profiles, which are fundamentally modified under weak propagational diffraction. The case of a profiled beam readout with propagational diffraction may be analyzed using a transfer function approach based on 2-D Laplace transforms. In a second series of investigations, dynamic readout from a cross-beam volume hologram recorded with two orthogonal uniform plane waves is considered for various dependences of the refractive index modulation with intensity. Typically, refractive index profiles that are proportional to the ...

Volume Holographic Optical Elements, 2016 National Central University

#### Volume Holographic Optical Elements, Ching-Cherng Sun, Partha P. Banerjee

*Partha Banerjee*

The final two papers are concerned with the analysis of novel holograms. Banerjee et al. investigate holographic recording and reconstruction for edge-lit holograms recorded in a 90-degree geometry. Various cases of recording and readout that incorporate propagational diffraction have been modeled. It is shown that the 90-degree geometry can result in beam shaping, as evidenced through preliminary experimental results with photorefractive lithium niobate. Nguyen et al. propose a new approach for designing computer-generated holograms. An artificial neural network is used to initiate the genetic algorithm so that the high computation cost of genetic algorithms for synthesizing holograms is significantly reduced ...

Rotation-Invariant Synthetic Discriminant Function Filter For Pattern Recognition, 2016 University of South Alabama

#### Rotation-Invariant Synthetic Discriminant Function Filter For Pattern Recognition, Vahid R. Riasati, Partha P. Banerjee, Mustafa A. G. Abushagur, Kenneth B. Howell

*Partha Banerjee*

The ring synthetic discriminant function (RSDF) filter for rotation-invariant response is discussed for pattern recognition. This method uses one half of a slice of the Fourier transform of the object to generate the transfer function of the filter. This is accomplished by rotating the one half of a slice in the Fourier domain through 2π rad about the zero-frequency point of the Fourier plane. This filter has the advantage of always matching at least one half of a slice of the Fourier transform of any rotation of the image. An analytical discussion of the filter construction and correlation results are ...

On A Simple Derivation Of The Fresnel Diffraction Formula And A Transfer Function Approach To Wave Propagation, 2016 University of Dayton

#### On A Simple Derivation Of The Fresnel Diffraction Formula And A Transfer Function Approach To Wave Propagation, Partha P. Banerjee, Ting-Chung Poon

*Partha Banerjee*

The Fresnel diffraction formula is straightforwardly obtained by solving a partial differential equation (PDE) for envelope propagation using Fourier transform techniques. The PDE, in turn, can be derived from the dispersion relation of a linear medium by employing a simple operator formalism. The transfer function and impulse response of propagation follows as a spin‐off and is used to solve illustrative problems. Huygens’ principle is visualized as a consequence of the convolution property of linear systems.

Notch Spatial Filtering With An Acousto-Optic Modulator, 2016 University of Dayton

#### Notch Spatial Filtering With An Acousto-Optic Modulator, Partha P. Banerjee, Dongqing Cao, Ting-Chung Poon

*Partha Banerjee*

The role of acousto-optic (AO) modulators in programmable real-time image processing has recently been demonstrated. For fully investigating the image-processing capabilities of the AO modulator, general techniques to derive spatial transfer functions are needed for a variety of physical situations. We develop a technique to determine the spatial transfer functions numerically for various cases of beam incidence on an AO modulator. Normal incidence and incidence at twice the Bragg angle are investigated as examples for which double-sided and single-sided notch spatial filtering, respectively, are achieved. The observed spatial-filtering characteristics are reconciled with simple intuitive physical arguments.

Nonlinear Transverse Effects In Second-Harmonic Generation, 2016 Syracuse University

#### Nonlinear Transverse Effects In Second-Harmonic Generation, Pawel Pliszka, Partha P. Banerjee

*Partha Banerjee*

We study a three-dimensional model of interaction of fundamental-frequency and second-harmonic beams in a quadratically nonlinear medium. Numerical simulations of the three-dimensional propagation problem in the presence of diffraction and anisotropy are performed under the paraxial approximation. The role of the transverse effects in various regimes is investigated. We demonstrate the effect of phase modulation and an induced nonlinear focusing during the interaction of the fundamental frequency with the generated second harmonic.