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Low Rank Approximation Method For Efficient Green's Function Calculation Of Dissipative Quantum Transport, Lang Zeng, Yu He, Michael Povolotskyi, Xiao Yan Liu, Gerhard Klimeck, Tillmann Kubis Nov 2013

Low Rank Approximation Method For Efficient Green's Function Calculation Of Dissipative Quantum Transport, Lang Zeng, Yu He, Michael Povolotskyi, Xiao Yan Liu, Gerhard Klimeck, Tillmann Kubis

Gerhard Klimeck

In this work, the low rank approximation concept is extended to the non-equilibrium Green’s function (NEGF) method to achieve a very efficient approximated algorithm for coherent and incoherent electron transport. This new method is applied to inelastic transport in various semiconductor nanodevices. Detailed benchmarks with exact NEGF solutions show (1) a very good agreement between approximated and exact NEGF results, (2) a significant reduction of the required memory, and (3) a large reduction of the computational time (a factor of speed up as high as 150 times is observed). A non-recursive solution of the inelastic NEGF transport equations of a …


Airborne Dual-Polarization Observations Of The Sea-Surface Nrcs At C-Band In High Winds, Joseph W. Sapp, Stephen J. Frasier, Jason Dvorsky, Paul S. Chang, Zorana Jelenak Jun 2013

Airborne Dual-Polarization Observations Of The Sea-Surface Nrcs At C-Band In High Winds, Joseph W. Sapp, Stephen J. Frasier, Jason Dvorsky, Paul S. Chang, Zorana Jelenak

Joseph W Sapp

Airborne dual-polarization observations of sea-surface normalized radar cross-section (NRCS) were conducted over the North Atlantic during Jan–Feb 2011. Observations were made using the University of Massachusetts’ Imaging Wind and Rain Airborne Profiler (IWRAP) radar system installed on the National Oceanic and Atmospheric Administration’s (NOAA) WP-3D research aircraft during several winter storm events to determine the high-wind response of the sea-surface NRCS for both horizontal and vertical polarizations. During the flights, the aircraft performed several constant-roll circle maneuvers to allow collection of NRCS over a range of incidence angles. We find consistency with prior reports in the polarization ratio observed at …


Enabling Interplanetary Small Spacecraft Science Missions With Model Based Data Analysis, Jeremy Straub Jun 2013

Enabling Interplanetary Small Spacecraft Science Missions With Model Based Data Analysis, Jeremy Straub

Jeremy Straub

Small spacecraft operating outside of Earth orbit are significantly constrained by the communica- tions link available to them. This is particularly true for stand-alone craft that must rely on their own antenna and transmission systems (for which gain and available power generation are limited by form factor); it is also applicable to ‘hitchhiker’-style missions which may be able to utilize (quite likely very limited amounts of) time on the primary spacecraft’s communications equip- ment for long-haul transmission.

This poster presents the adaptation of the Model-Based Transmission Reduction (MBTR) frame- work’s Model-Based Data Analysis (MBDA) component for use on an interplanetary …


Wireless Transmission Network : A Imagine, Radhey Shyam Meena Engineer, Neeraj Kumar Garg Asst.Prof Apr 2013

Wireless Transmission Network : A Imagine, Radhey Shyam Meena Engineer, Neeraj Kumar Garg Asst.Prof

Radhey Shyam Meena

World cannot be imagined without electrical power. Generally the power is transmitted through transmission networks. This paper describes an original idea to eradicate the hazardous usage of electrical wires which involve lot of confusion in particularly organizing them. Imagine a future in which wireless power transfer is feasible: cell phones, household robots, mp3 players, laptop computers and other portable electronic devices capable of charging themselves without ever being plugged in freeing us from that final ubiquitous power wire. This paper includes the techniques of transmitting power without using wires with an efficiency of about 95% with non-radioactivemethods. In this paper …


Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er., Deepa Sharma Mar 2013

Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er., Deepa Sharma

Radhey Shyam Meena

Grid-connected solar PV dramatically changes the load profile of an electric utility customer. The expected widespread adoption of solar generation by customers on the distribution system poses significant challenges to system operators both in transient and steady state operation, from issues including voltage swings, sudden weather-induced changes in generation, and legacy protective devices designed with one-way power flow in mind


Exposing Multiple User-Specific Data Denominated Products From A Single Small Satellite Data Stream, Atif F. Mohammad,, Emanuel Grant, Jeremy Straub, Ronald Marsh, Scott Kerlin Mar 2013

Exposing Multiple User-Specific Data Denominated Products From A Single Small Satellite Data Stream, Atif F. Mohammad,, Emanuel Grant, Jeremy Straub, Ronald Marsh, Scott Kerlin

Jeremy Straub

This paper presents a research work on small satellite data stream and related distribution to associated stakeholders, which is a field that needs to get explored in more detail. The algorithm that is presented to extract USDDP (User-Specific Data Denominated Products) is a self managing body, which will be within as Open Space Box environment or OSBE as a novel idea. It contains an individual stream transmitted by the small satellite, which later is to be converted into USDDP. The context defined here deals with area in detail. Contexts are vitally important because they control, influence and affect everything within …


Open Space Box Model: Service Oriented Architecture Framework For Small Spacecraft Collaboration And Control, Atif F. Mohammad, Jeremy Straub Feb 2013

Open Space Box Model: Service Oriented Architecture Framework For Small Spacecraft Collaboration And Control, Atif F. Mohammad, Jeremy Straub

Jeremy Straub

A Cubesat is a small satellite with very less competence to compute, it requires software engineering techniques, which can enhance the computational power for this small box. A model-driven approach of software engineering, which is called OSBM or Open Space Box Modeling technique, is an excellent solution to this re-source maximization challenge. OSBM facilitates apparition of the key solution pro-cesses computation and satellite related data elements using Service Oriented Ar-chitecture 3.0 (SOA 3.0) as base to work on to design services. The key challenges that can be handled by utilizing OSBM include concurrent operation and tasking of few as five …


Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er. Jan 2013

Battery Energy Storage System In Solar Power Generation, Radhey Shyam Meena Er.

Radhey Shyam Meena

As solar photovoltaic power generation becomes more commonplace, the inherent intermittency of the solar resource poses one of the great challenges to those who would design and implement the next generation smart grid. Specifically, grid-tied solar power generation is a distributed resource whose output can change extremely rapidly, resulting in many issues for the distribution system operator with a large quantity of installed photovoltaic devices. Battery energy storage systems are increasingly being used to help integrate solar power into the grid. These systems are capable of absorbing and delivering both real and reactive power with sub-second response times. With these …