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Mobile Map Browsers: Anticipated User Interaction For Data Pre-Fetching, Benjamin T. Weber 2010 The University of Maine

Mobile Map Browsers: Anticipated User Interaction For Data Pre-Fetching, Benjamin T. Weber

Electronic Theses and Dissertations

When browsing a graphical display of geospatial data on mobile devices, users typically change the displayed maps by panning, zooming in and out, or rotating the device. Limited storage space on mobile devices and slow wireless communications, however, impede the performance of these operations. To overcome the bottleneck that all map data to be displayed on the mobile device need to be downloaded on demand, this thesis investigates how anticipated user interactions affect intelligent pre-fetching so that an on-demand download session is extended incrementally. User interaction is defined as a set of map operations that each have corresponding effects on ...


Parameterizable Network-On-Chip Emulation Framework, Jaya Suseela 2010 University of Nevada, Las Vegas

Parameterizable Network-On-Chip Emulation Framework, Jaya Suseela

UNLV Theses, Dissertations, Professional Papers, and Capstones

Networks-on-Chip (NoCs) have been proposed as a promising solution to complex on-chip communication problems. But there is no public accessible HDL synthesizable NoC framework which connects industrial level cores and runs real applications on them. Moreover, many challenging research problems remain unsolved at all levels of design abstraction; design exploration of NoC architecture for applications, scheduling and mapping algorithms, evaluation of switching, topology or routing algorithm for efficient execution of application and optimizing communication cost, area, energy etc Solution to solve the above problem calls for the development of synthesizable, parameterizable NoC Framework that would evaluate and implement the above ...


Design And Modeling Of A 40w Microwave Switch In Qfn 2x2 Package, Chin-Leong Lim 2010 Avago Technologies, Malaysia

Design And Modeling Of A 40w Microwave Switch In Qfn 2x2 Package, Chin-Leong Lim

Chin-Leong Lim

This paper describes a Quad Flat Non-lead (QFN 2x2) packaged PIN diode switch that is capable of handling Continuous Wave (CW) power up to 40W and WCDMA signal up to 10W. The target application is the Transmit (Tx) arm of a Transmit Receive (TR) switch for cellular base-stations. The part was developed in response to this market segment's aggressive cut-cutting pressure. Prior designs relied on more expensive ceramic packages.


Rf Shields That Can Be Integrated With Ic Test Handlers, Chin-Leong Lim 2010 Avago Technologies, Malaysia

Rf Shields That Can Be Integrated With Ic Test Handlers, Chin-Leong Lim

Chin-Leong Lim

This paper describes several radio frequency interference shields that have been developed for integration with high-speed bulk-input turret-test IC handlers. The shields were developed to mitigate interference to noise figure measurements of Low Noise Amplifier components. Two categories of shielded enclosures were evaluated for shielding effectiveness and ease of incorporation into the existing machines and manufacturing processes. The first category enclosed the handler's working area in its entirety, while the second one enclosed the testboard only. Variation in the testboard shield design was required to suit different collet trajectories between handler models. The shielding effectiveness (SE) was measured according ...


Super-Flexibility Interview I & Ii, Stuart Evans 2010 Carnegie Mellon University

Super-Flexibility Interview I & Ii, Stuart Evans

Silicon Valley Campus

In Super-Flexibility for Knowledge Enterprises:
A Toolkit for Dynamic Adaptation
(Springer, 2010), authors and
educators, Homa Bahrami and Stuart Evans
provide a “toolkit” to help organizations and
teams become “super-flexible” in a dynamic
world. They define “super-flexibility” as the capacity
to transform by adapting to new realities,
underpinned by the ability to withstand
turbulence by creating stable anchors. Based
on 25 years of field research, advisory work,
and professional experience in Silicon Valley,
Bahrami and Evans present a cross-functional
general management toolkit for strategizing,
organizing, leading, and ultimately re-inventing
knowledge enterprises. Part I of this
interview will focus on the ...


Software Engineering Issues For Mobile Application Development, Tony Wasserman 2010 Carnegie Mellon University

Software Engineering Issues For Mobile Application Development, Tony Wasserman

Silicon Valley Campus

This paper provides an overview of important software engineering research issues related to the development of applications that run on mobile devices. Among the topics are development processes, tools, user interface design, application portability, quality, and security.


Uwb-Fsk: Performance Tradeoffs For High And Low Complexity Receivers, Todor Cooklev, Fernando Ramirez-Mireles, G. A. Paredes-Orozco 2010 Indiana University - Purdue University Fort Wayne

Uwb-Fsk: Performance Tradeoffs For High And Low Complexity Receivers, Todor Cooklev, Fernando Ramirez-Mireles, G. A. Paredes-Orozco

Engineering Faculty Publications

In this work we explore flexible modulations toallow demodulation using receivers with different complexityand cost. More specifically, we study pulse-based ultrawideband (UWB) communications over channels with densemultipath effects using frequency shift keying (FSK) datamodulation. Our aim is to explore the performance tradeoffsbetween high and low complexity receivers. For this purposewe determine the performance of coherent, non-coherent andmismatched (e.g., non-coherent detection using templatesconsisting of a single path) demodulators. We take intoaccount the influence of the frequency response of the antennasystem and the effects of the frequency selectivity of themultipath channel. Given a specific channel condition, wederive expressions for the bit ...


Software Engineering Issues For Mobile Application Development, Tony Wasserman 2010 Carnegie Mellon University

Software Engineering Issues For Mobile Application Development, Tony Wasserman

Tony Wasserman

This paper provides an overview of important software engineering research issues related to the development of applications that run on mobile devices. Among the topics are development processes, tools, user interface design, application portability, quality, and security.


Describing Radio Hardware And Software Using Owl For Over-The-Air Software Download, Todor Cooklev, Stanchev, David Clendenen 2010 Indiana University - Purdue University Fort Wayne

Describing Radio Hardware And Software Using Owl For Over-The-Air Software Download, Todor Cooklev, Stanchev, David Clendenen

Engineering Faculty Publications

Recently, several researchers have discovered the need for radios to use description techniques. Previous research describes information such as the current frequency band, waveform, and so on. However, this information is presented at a level that is not sufficient to determine software/hardware compatibility for over-the-air software download. For example, a device should not attempt to download a wideband waveform if its radio front-end is only narrowband, or if its baseband hardware cannot provide the required MIPS for the new waveform. Over-the-air software download is one of the most interesting features of software-defined radios. The compatibility between software and hardware ...


Microstrip-Fed Wideband Circularly Polarized Printed Antenna, Xiulong Bao, Max Ammann, Patrick McEvoy 2010 Dublin Institute of Technology

Microstrip-Fed Wideband Circularly Polarized Printed Antenna, Xiulong Bao, Max Ammann, Patrick Mcevoy

Articles

A wideband circularly-polarized printed antenna is proposed, which employs an asymmetrical dipole and a slit in the ground plane which are fed by an L-shaped microstrip feedline using a via. The proposed antenna geometry is arranged so that the orthogonal surface currents, which are generated in the dipole, feedline and ground plane, have the appropriate phase to provide circular polarization. A parametric study of the key parameters is made and the mechanism for circular polarization is described. The measured results show that the impedance bandwidth is approximately 1.34 GHz (2.45 GHz to 3.79 GHz) and the 3 ...


The Impact Of Reprovisioning On The Choice Of Shared Versus Dedicated Networks, Soumya Sen, Kristin Yamauchi, Roch Guerin, Kartik Hosanagar 2010 University of Pennsylvania

The Impact Of Reprovisioning On The Choice Of Shared Versus Dedicated Networks, Soumya Sen, Kristin Yamauchi, Roch Guerin, Kartik Hosanagar

Departmental Papers (ESE)

As new network services emerge, questions about service deployment and network choices arise. Although shared networks, such as the Internet, offer many advantages, combining heterogeneous services on the same network need not be the right answer as it comes at the cost of increased complexity. Moreover, deploying new services on dedicated networks is becoming increasingly viable, thanks to virtualization technologies. In this work, we introduce an analytical framework that gives Internet Service Providers the ability to explore the trade-offs between shared and dedicated network infrastructures. The framework accounts for factors such as the presence of demand uncertainty for new services ...


Integration Of Antennas And Solar Cells For Autonomous Communication Systems, Maria Jose Roo Ons 2010 Dublin Institute of Technology

Integration Of Antennas And Solar Cells For Autonomous Communication Systems, Maria Jose Roo Ons

Doctoral

Solar energy is becoming an attractive alternative for powering autonomous communication systems. These devices often involve the use of separate photovoltaics and antennas, which demand a compromise in the utilization of the limited space available. This thesis deals with the design, analysis, fabrication and validation of different techniques for the integration of antennas and solar cells in a single multifunctional device. Four different photovoltaic technologies are considered within this work, namely, polycrystalline silicon (poly-Si), monocrystalline (mono-Si) emitter-wrap-through (EWT) rear contact solar cells, amorphous silicon (a-Si) thin film on glass substrate, and bifacial solar cells. The use of a poly-Si solar ...


Lna Based On A Low Cost (~Usd1.30) Commercial Gaas Phemt Mmic Offers Wideband (0.4~1.4 Ghz) And Room-Temperature Low Noise (~0.3 Db) Performances That Satisfy The Ska Low Cost And No-Cooling Requirement, Chin-Leong Lim 2010 Avago Technologies, Malaysia

Lna Based On A Low Cost (~Usd1.30) Commercial Gaas Phemt Mmic Offers Wideband (0.4~1.4 Ghz) And Room-Temperature Low Noise (~0.3 Db) Performances That Satisfy The Ska Low Cost And No-Cooling Requirement, Chin-Leong Lim

Chin-Leong Lim

Introduction: New generations of radio telescopes such as the Square Kilometre Array consist of millions of receivers scattered over a continent. The array’s quantity and geographic considerations ruled out the traditional radio astronomy LNA implementation; i.e. costly InP devices cooled by high-maintenance closed-cycle helium (He) refrigerators. Several LNA designs have been proposed to address the cost and room-temperature operation constraints but none appear a clear winner. Peltier and package-scale cooling have also been proposed as a lower cost/maintenance alternative to He cooling but when multiplied by the quantity required can still carve a significant chunk of the ...


Consideration Of Dispersion And Group Velocity Dispersion In The Determination Of Velocities Of Electromagnetic Propagation, Monish Ranjan Chatterjee, Partha P. Banerjee 2010 University of Dayton

Consideration Of Dispersion And Group Velocity Dispersion In The Determination Of Velocities Of Electromagnetic Propagation, Monish Ranjan Chatterjee, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Electromagnetic (EM) propagation velocities play an important role in the determination of power and energy flow in materials and interfaces. It is well known that group and phase velocities need to be in opposition in order to achieve negative refractive index.

Recently, we have shown that considerable differences may exist in phase, group and signal/energy velocities for normal and anomalous dispersion, especially near dielectric resonances. This paper examines the phase and group velocities in the presence of normal and anomalous dispersion, and group velocity dispersion (GVD), which requires introduction of the second order coefficient in the permittivity and permeability ...


Performance Measures In Acousto-Optic Chaotic Signal Encryption System Subject To Parametric Variations And Additive Noise, Monish Ranjan Chatterjee, Anjan K. Ghosh, Mohammed A. Al-Saedi 2010 University of Dayton

Performance Measures In Acousto-Optic Chaotic Signal Encryption System Subject To Parametric Variations And Additive Noise, Monish Ranjan Chatterjee, Anjan K. Ghosh, Mohammed A. Al-Saedi

Electrical and Computer Engineering Faculty Publications

Signal encryption and recovery using chaotic optical waves has been a subject of active research in the past 10 years. Since an acousto-optic Bragg cell with zeroth- and first-order feedback exhibits chaotic behavior past the threshold for bistability, such a system was recently examined for possible chaotic encryption using a low-amplitude sinusoidal signal applied via the bias input of the sound cell driver.

Subsequent recovery of the message signal was carried out via a heterodyne strategy employing a locally generated chaotic carrier, with threshold parameters matched to the transmitting Bragg cell. The simulation results, though encouraging, were limited to relatively ...


Improved Compression Of Network Coding Vectors Using Erasure Decoding And List Decoding, Shizheng Li, Aditya Ramamoorthy 2010 Iowa State University

Improved Compression Of Network Coding Vectors Using Erasure Decoding And List Decoding, Shizheng Li, Aditya Ramamoorthy

Electrical and Computer Engineering Publications

Practical random network coding based schemes for multicast include a header in each packet that records the transformation between the sources and the terminal. The header introduces an overhead that can be significant in certain scenarios. In previous work, parity check matrices of error control codes along with error decoding were used to reduce this overhead. In this work we propose novel packet formats that allow us to use erasure decoding and list decoding. Both schemes have a smaller overhead compared to the error decoding based scheme, when the number of sources combined in a packet is not too small.


Differentially Encoded Quadrature Phase Shift Key Communication And Real-Time Implementation, Robert Walton Conant 2010 Boise State University

Differentially Encoded Quadrature Phase Shift Key Communication And Real-Time Implementation, Robert Walton Conant

Boise State University Theses and Dissertations

Robust communication methods are integral to advances in modern technology. Software defined radios (SDRs) have been the chief instruments of communication for the last three decades. Upcoming generations of wireless networks and phone systems depend on successful implementations of increasingly sophisticated software defined modulation methods. The challenges presented by encoding, modulation, signal conditioning, timing, and decision algorithms are non-trivial. Adapting to the impacts of wired and wireless channels adds further complexity.

While not comprehensive on the subject of communications, this text serves to introduce the practical concepts of binary communications, modulation methods, the digital signal processor (DSP), and software defined ...


Minimum Cost Content Distribution Using Network Coding: Replication Vs. Coding At The Source Nodes, Shurui Huang, Aditya Ramamoorthy, Muriel Médard 2010 Iowa State University

Minimum Cost Content Distribution Using Network Coding: Replication Vs. Coding At The Source Nodes, Shurui Huang, Aditya Ramamoorthy, Muriel Médard

Electrical and Computer Engineering Conference Papers, Posters and Presentations

Abstract: Consider a large file that needs to be multicast over a network to a given set of terminals. Storing the file at a single server may result in server overload. Accordingly, there are distributed storage solutions that operate by dividing the file into pieces and placing copies of the pieces (replication) or coded versions of the pieces (coding) at multiple source nodes. Suppose that the cost of a given network coding based solution to this problem is defined as the sum of the storage cost and the cost of the flows required to support the multicast. In this work ...


Wideband Limiter Fits Sot-323 Pack, Chin-Leong Lim 2010 Avago Technologies, Malaysia

Wideband Limiter Fits Sot-323 Pack, Chin-Leong Lim

Chin-Leong Lim

Limiters protect wireless receiver front-ends from damage due to signal overload. The Schottky-PIN limiter is more protective than the self-biased PIN limiter because the former's limiting threshold is ~10 dB lower. Present implementation of the Schottky-PIN limiter use separate PIN and Schottky diodes. Additionally, some prior knowledge is necessary to select the correct PIN and Schottky diodes for limiter service. To miniaturize the limiter and to simplify the diode selection process, we combined a pair of limiter-optimized PIN and Schottky diodes into a compact and low-cost SOT-323 package. This paper describes the design, fabrication and experimental validation of the ...


Maximum-Likelihood Sequence Detector For Dynamic Mode High Density Probe Storage, Naveen Kumar, Pranav Agarwal, Aditya Ramamoorthy, Murti V. Salapaka 2010 Iowa State University

Maximum-Likelihood Sequence Detector For Dynamic Mode High Density Probe Storage, Naveen Kumar, Pranav Agarwal, Aditya Ramamoorthy, Murti V. Salapaka

Electrical and Computer Engineering Conference Papers, Posters and Presentations

There is an increasing need for high density data storage devices driven by the increased demand of consumer electronics. In this work, we consider a data storage system that operates by encoding information as topographic profiles on a polymer medium. A cantilever probe with a sharp tip (few nm radius) is used to create and sense the presence of topographic profiles, resulting in a density of few Tb per in.2. The prevalent mode of using the cantilever probe is the static mode that is harsh on the probe and the media. In this article, the high quality factor dynamic ...


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