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2009

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Articles 721 - 750 of 4158

Full-Text Articles in Engineering

Effect Of Manufacturer's Joint Fastening Techniques On Compression Strength Of Corrugated Fiberboard Boxes, Jay Singh, A. Attema, Eric Olsen, Keith Vorst Oct 2009

Effect Of Manufacturer's Joint Fastening Techniques On Compression Strength Of Corrugated Fiberboard Boxes, Jay Singh, A. Attema, Eric Olsen, Keith Vorst

Industrial Technology and Packaging

A flat piece of corrugated fiberboard, which has been cut, slotted and scored, is often referred to as a box blank. For several box styles, in order to convert the box blank into a box, its two ends must be fastened together with tape, staples or adhesives such as water soluble glues. The location at which the two ends meet is known as the manufacturer's joint. There are several variations within the three fastening techniques mentioned with most corrugated box manufacturers following their own protocols for fastening the manufacturer's joints. This study explored the compression and tensile strengths of RSC …

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Glenn Research Center Quantum Communicator Receiver Design And Development, Murad Hizlan, John D. Lekki, Binh V. Nguyen Oct 2009

Glenn Research Center Quantum Communicator Receiver Design And Development, Murad Hizlan, John D. Lekki, Binh V. Nguyen

Electrical and Computer Engineering Faculty Publications

We investigate, design, and develop a prototype real-time synchronous receiver for the second-generation quantum communicator recently developed at the National Aeronautics and Space Administration (NASA) Glenn Research Center. This communication system exploits the temporal coincidences between simultaneously fired low-power laser sources to communicate at power levels several orders of magnitude less than what is currently achievable through classical means, with the ultimate goal of creating ultra-low-power microsize optical communications and sensing devices. The proposed receiver uses a unique adaptation of the early-late gate method for symbol synchronization and a newly identified 31-bit synchronization word for frame synchronization. This receiver, implemented …

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Identification Of The [Fefe]-Hydrogenase Responsible For Hydrogen Generation In Thermoanaerobacterium Saccharolyticum And Demonstration Of Increased Ethanol Yield Via Hydrogenase Knockout, A. Joe Shaw, David A. Hogsett, Lee R. Lynd Oct 2009

Identification Of The [Fefe]-Hydrogenase Responsible For Hydrogen Generation In Thermoanaerobacterium Saccharolyticum And Demonstration Of Increased Ethanol Yield Via Hydrogenase Knockout, A. Joe Shaw, David A. Hogsett, Lee R. Lynd

Dartmouth Scholarship

Three putative hydrogenase enzyme systems in Thermoanaerobacterium saccharolyticum were investigated at the genetic, mRNA, enzymatic, and phenotypic levels. A four-gene operon containing two [FeFe]-hydrogenase genes, provisionally termed hfs (hydrogenase-Fe-S), was found to be the main enzymatic catalyst of hydrogen production. hfsB, perhaps the most interesting gene of the operon, contains an [FeFe]-hydrogenase and a PAS sensory domain and has several conserved homologues among clostridial saccharolytic, cellulolytic, and pathogenic bacteria. A second hydrogenase gene cluster, hyd, exhibited methyl viologen-linked hydrogenase enzymatic activity, but hyd gene knockouts did not influence the hydrogen yield of …

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Scalable Detection Of Partial Near-Duplicate Videos By Visual-Temporal Consistency, Hung-Khoon Tan, Chong-Wah Ngo, Richang Hong, Tat-Seng Chua Oct 2009

Scalable Detection Of Partial Near-Duplicate Videos By Visual-Temporal Consistency, Hung-Khoon Tan, Chong-Wah Ngo, Richang Hong, Tat-Seng Chua

Research Collection School Of Computing and Information Systems

Following the exponential growth of social media, there now exist huge repositories of videos online. Among the huge volumes of videos, there exist large numbers of near-duplicate videos. Most existing techniques either focus on the fast retrieval of full copies or near-duplicates, or consider localization in a heuristic manner. This paper considers the scalable detection and localization of partial near-duplicate videos by jointly considering visual similarity and temporal consistency. Temporal constraints are embedded into a network structure as directed edges. Through the structure, partial alignment is novelly converted into a network flow problem where highly efficient solutions exist. To precisely …

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Towards Google Challenge: Combining Contextual And Social Information For Web Video Categorization, Xiao Wu, Wan-Lei Zhao, Chong-Wah Ngo Oct 2009

Towards Google Challenge: Combining Contextual And Social Information For Web Video Categorization, Xiao Wu, Wan-Lei Zhao, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

Web video categorization is a fundamental task for web video search. In this paper, we explore the Google challenge from a new perspective by combing contextual and social information under the scenario of social web. The semantic meaning of text (title and tags), video relevance from related videos, and user interest induced from user videos, are integrated to robustly determine the video category. Experiments on YouTube videos demonstrate the effectiveness of the proposed solution. The performance reaches 60% improvement compared to the traditional text based classifiers.

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Sharing Mobile Multimedia Annotations To Support Inquiry-Based Learning Using Mobitop, Khasfariyati Razikin, Dion Hoe-Lian Goh, Yin-Leng Theng, Quang Minh Nguyen, Thi Nhu Quynh Kim, Ee Peng Lim, Chew-Hung Chang, Kalyani Chatterjea, Aixin Sun Oct 2009

Sharing Mobile Multimedia Annotations To Support Inquiry-Based Learning Using Mobitop, Khasfariyati Razikin, Dion Hoe-Lian Goh, Yin-Leng Theng, Quang Minh Nguyen, Thi Nhu Quynh Kim, Ee Peng Lim, Chew-Hung Chang, Kalyani Chatterjea, Aixin Sun

Research Collection School Of Computing and Information Systems

Mobile devices used in educational settings are usually employed within a collaborative learning activity in which learning takes place in the form of social interactions between team members while performing a shared task. We introduce MobiTOP (Mobile Tagging of Objects and People), a geospatial digital library system which allows users to contribute and share multimedia annotations via mobile devices. A key feature of MobiTOP that is well suited for collaborative learning is that annotations are hierarchical, allowing annotations to be annotated by other users to an arbitrary depth. A group of student-teachers involved in an inquiry-based learning activity in geography …

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Distribution-Based Concept Selection For Concept-Based Video Retrieval, Juan Cao, Hongfang Jing, Chong-Wah Ngo, Yongdong Zhang Oct 2009

Distribution-Based Concept Selection For Concept-Based Video Retrieval, Juan Cao, Hongfang Jing, Chong-Wah Ngo, Yongdong Zhang

Research Collection School Of Computing and Information Systems

Query-to-concept mapping plays one of the keys to concept-based video retrieval. Conventional approaches try to find concepts that are likely to co-occur in the relevant shots from the lexical or statistical aspects. However, the high probability of co-occurrence alone cannot ensure its effectiveness to distinguish the relevant shots from the irrelevant ones. In this paper, we propose distribution-based concept selection (DBCS) for query-to-concept mapping by analyzing concept score distributions of within and between relevant and irrelevant sets. In view of the imbalance between relevant and irrelevant examples, two variants of DBCS are proposed respectively by considering the two-sided and onesided …

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Orbital Stark Effect And Quantum Confinement Transition Of Donors In Silicon, Rajib Rahman, G P. Lansbergen, Seung H. Park, J Verduijn, Gerhard Klimeck, S Rogge, Lloyd Cl Hollenberg Oct 2009

Orbital Stark Effect And Quantum Confinement Transition Of Donors In Silicon, Rajib Rahman, G P. Lansbergen, Seung H. Park, J Verduijn, Gerhard Klimeck, S Rogge, Lloyd Cl Hollenberg

Birck and NCN Publications

Adiabatic shuttling of single impurity bound electrons to gate-induced surface states in semiconductors has attracted much attention in recent times, mostly in the context of solid-state quantum computer architecture. A recent transport spectroscopy experiment for the first time was able to probe the Stark shifted spectrum of a single donor in silicon buried close to a gate. Here, we present the full theoretical model involving large-scale quantum mechanical simulations that was used to compute the Stark shifted donor states in order to interpret the experimental data. Use of atomistic tight-binding technique on a domain of over a million atoms helped …

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Orbital Stark Effect And Quantum Confinement Transition Of Donors In Silicon, Rajib Rahman, G P. Lansbergen, Seung H. Park, J Verduijn, Gerhard Klimeck, S Rogge, Lloyd Cl Hollenberg Oct 2009

Orbital Stark Effect And Quantum Confinement Transition Of Donors In Silicon, Rajib Rahman, G P. Lansbergen, Seung H. Park, J Verduijn, Gerhard Klimeck, S Rogge, Lloyd Cl Hollenberg

Birck and NCN Publications

Adiabatic shuttling of single impurity bound electrons to gate-induced surface states in semiconductors has attracted much attention in recent times, mostly in the context of solid-state quantum computer architecture. A recent transport spectroscopy experiment for the first time was able to probe the Stark shifted spectrum of a single donor in silicon buried close to a gate. Here, we present the full theoretical model involving large-scale quantum mechanical simulations that was used to compute the Stark shifted donor states in order to interpret the experimental data. Use of atomistic tight-binding technique on a domain of over a million atoms helped …

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A Comparison Of Algorithms That Estimate The Effectiveness Of Commercial Airline Boarding Strategies, Dalila Giraldo Oct 2009

A Comparison Of Algorithms That Estimate The Effectiveness Of Commercial Airline Boarding Strategies, Dalila Giraldo

Doctoral Dissertations and Master's Theses

The number of passengers carried by commercial aircraft has increased dramatically over the past 50 years, closely in-step with advances in aircraft design. This makes unloading and loading an aircraft, called turn-around time, critical to the success of the airport, the aircraft and the airlines. A number of mathematical algorithms have been developed over the years that purport to determine the most efficient boarding strategy for passengers by decreasing turn time. This thesis evaluated the boarding strategies most often used by the airlines and algorithms used to predict boarding efficiency. The models used were obtained from the literature and from …

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Effects Of Gaussian Fields On The Stability Of Inhomogeneously Broadened Lasers, Pitak Chenkosol, Lee W. Casperson Oct 2009

Effects Of Gaussian Fields On The Stability Of Inhomogeneously Broadened Lasers, Pitak Chenkosol, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Under some conditions, spontaneous coherent pulsations are known to occur in the output beams of inhomogeneously broadened laser oscillators. These lasers typically operate with a Gaussian transverse field distribution, while the corresponding theoretical models assume a uniform-plane-wave field. The effects of a Gaussian field on the stability criteria of single-mode inhomogeneously broadened ring laser oscillators are considered in this study. It is found that in comparison to a plane wave a Gaussian field variation still permits low-threshold spontaneous pulsations but reduces the parameter space over which these pulsations can be observed.

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Towards Supervised Autonomous Task Completion Using An In Vivo Surgical Robot, Jason J. Dumpert Oct 2009

Towards Supervised Autonomous Task Completion Using An In Vivo Surgical Robot, Jason J. Dumpert

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Laparoscopy is a minimally invasive alternative to traditional abdominal surgery. Unlike traditional surgery, a laparoscopic procedure can be completed using small incisions. The use of these small incision results in reduced pain to the patient, shorter recovery times, and less trauma to skin, muscle and other tissues. However, these benefits to the patient are offset by the increased difficulty to the surgeon performing the procedure. These difficulties include reduced dexterity, reduced perception, and longer procedure times. The use of small in vivo robotic devices in minimally invasive surgery is one possible solution to these problems. The movement of these devices …

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Mining Globally Distributed Frequent Subgraphs In A Single Labeled Graph, Xing Jiang, Hui Xiong, Chen Wang, Ah-Hwee Tan Oct 2009

Mining Globally Distributed Frequent Subgraphs In A Single Labeled Graph, Xing Jiang, Hui Xiong, Chen Wang, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Recent years have observed increasing efforts on graph mining and many algorithms have been developed for this purpose. However, most of the existing algorithms are designed for discovering frequent subgraphs in a set of labeled graphs only. Also, the few algorithms that find frequent subgraphs in a single labeled graph typically identify subgraphs appearing regionally in the input graph. In contrast, for real-world applications, it is commonly required that the identified frequent subgraphs in a single labeled graph should also be globally distributed. This paper thus fills this crucial void by proposing a new measure, termed G-Measure, to find globally …

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Analyzing The Video Popularity Characteristics Of Large-Scale User Generated Content Systems, Meeyoung Cha, Haewoon Kwak, Pablo Rodriguez, Yong-Yeol Ahn, Sue Moon Oct 2009

Analyzing The Video Popularity Characteristics Of Large-Scale User Generated Content Systems, Meeyoung Cha, Haewoon Kwak, Pablo Rodriguez, Yong-Yeol Ahn, Sue Moon

Research Collection School Of Computing and Information Systems

User generated content (UGC), now with millions of video producers and consumers, is re-shaping the way people watch video and TV. In particular, UGC sites are creating new viewing patterns and social interactions, empowering users to be more creative, and generating new business opportunities. Compared to traditional video-on-demand (VoD) systems, UGC services allow users to request videos from a potentially unlimited selection in an asynchronous fashion. To better understand the impact of UGC services, we have analyzed the world's largest UGC VoD system, YouTube, and a popular similar system in Korea, Daum Videos. In this paper, we first empirically show …

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Analysis Of Tradeoffs Between Buffer And Qos Requirements In Wireless Networks, Raphael Rom, Hwee-Pink Tan Oct 2009

Analysis Of Tradeoffs Between Buffer And Qos Requirements In Wireless Networks, Raphael Rom, Hwee-Pink Tan

Research Collection School Of Computing and Information Systems

In this paper, we consider the scheduling problem where data packets from K input-flows need to be delivered to K corresponding wireless receivers over a heterogeneous wireless channel. Our objective is to design a wireless scheduler that achieves good throughput and fairness performance while minimizing the buffer requirement at each wireless receiver. This is a challenging problem due to the unique characteristics of the wireless channel. We propose a novel idea of exploiting both the long-term and short-term error behavior of the wireless channel in the scheduler design. In addition to typical first-order Quality of Service (QoS) metrics such as …

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Optimization Of Two-Way Post-Tensioned Concrete Floor Systems, Gaelyn B. Krauser Oct 2009

Optimization Of Two-Way Post-Tensioned Concrete Floor Systems, Gaelyn B. Krauser

Master's Theses

This thesis investigates a parametric study of a flat plate floor system designed using post-tensioning. The load balanced by the post-tensioning, the slab depth, and the strength of concrete were varied to create the parametric study of a hotel/condominium grid layout. In order to perform the parametric study, research was conducted on the development of post-tensioning, methods of analysis for two-way slab design, and post-tensioning methods of analysis. Design was conducted by hand through a series of Excel spreadsheets and compared to results found using the computer analysis program, ADAPT-PT. The designs found in the parametric study were then used …

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Regression Analysis Of Fracture Toughness For Secondary Osteons Located In Human Cortical Bone, Chase A. Fetzer Oct 2009

Regression Analysis Of Fracture Toughness For Secondary Osteons Located In Human Cortical Bone, Chase A. Fetzer

Master's Theses

An experiment was carried out in order to locate and quantify osteon types within a sample of cortical bone taken from a human tibia. This was done using a microscope-camera assembly and the BioQuant computer software. The results of this were correlated with a previous experiment’s results on fracture toughness so that an analysis could be run on the data in order to determine the factors that most affect the value of fracture toughness of this cortical bone. Results were examined closely and the analysis repeated until the author was satisfied that the best possible model for fracture toughness had …

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Application Of Systems Engineering To Rapid Prototyping For Close Air Support, John M. Colombi, Richard G. Cobb Oct 2009

Application Of Systems Engineering To Rapid Prototyping For Close Air Support, John M. Colombi, Richard G. Cobb

Faculty Publications

Twenty-first century military operations have brought forth many new challenges for the Armed Forces of the United States. One such challenge is with new operating environments, where current systems are not always effective. While it is desirable to apply a systems engineering approach to best meet critical user needs, there may be a misconception that systems engineering requires a lengthy and detailed process not nimble enough for a rapid prototyping effort. This article describes how a classic systems engineering methodology was successfully tailored to the rapid development of potential material solutions to meet a critical operational need. Key observations are …

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Flexor Reflex Decreases During Sympathetic Stimulation In Chronic Human Spinal Cord Injury, Mark Kevin Garrison, Brian D. Schmit Oct 2009

Flexor Reflex Decreases During Sympathetic Stimulation In Chronic Human Spinal Cord Injury, Mark Kevin Garrison, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

A better understanding of autonomic influence on motor reflex pathways in spinal cord injury is important to the clinical management of autonomic dysreflexia and spasticity in spinal cord injured patients. The purpose of this study was to examine the modulation of flexor reflex windup during episodes of induced sympathetic activity in chronic human spinal cord injury (SCI). We simultaneously measured peripheral vascular conductance and the windup of the flexor reflex in response to conditioning stimuli of electrocutaneous stimulation to the opposite leg and bladder percussion. Flexor reflexes were quantified using torque measurements of the response to a noxious electrical stimulus …

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Splenic Trauma As An Adverse Effect Of Torso-Protecting Side Airbags: Biomechanical And Case Evidence, Jason John Hallman, Karen J. Brasel, Narayan Yoganandan, Frank A. Pintar Oct 2009

Splenic Trauma As An Adverse Effect Of Torso-Protecting Side Airbags: Biomechanical And Case Evidence, Jason John Hallman, Karen J. Brasel, Narayan Yoganandan, Frank A. Pintar

Biomedical Engineering Faculty Research and Publications

Injury mechanisms from frontal airbags, first identified in anecdotal reports, are now well documented for pediatric, small female, and out-of-position occupants. In contrast, torso side airbags have not yet been consistently associated with specific injury risks in field assessments. To determine possible torso side airbag-related injuries, the present study identified crashes involving side airbags from reports within the CIREN, NASS, and SCI databases. Injury patterns were compared to patterns from lateral crashes in absence of side airbag. Splenic trauma (AIS 3+) was found present in five cases of torso side airbag deployment at lower impact severity (as measured by velocity …

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A Systematic Study Of Atomic Layer Deposition Of Platinum Nano-Scale Metallization Films And Their Application To Electrical Contacts In Porous Alumina Templates, Ngoc H. Tran Oct 2009

A Systematic Study Of Atomic Layer Deposition Of Platinum Nano-Scale Metallization Films And Their Application To Electrical Contacts In Porous Alumina Templates, Ngoc H. Tran

Electrical & Computer Engineering Theses & Dissertations

ln this thesis a comprehensive analysis is presented on nano-scale thin films of platinum deposited with Angstrom resolution by Atomic Layer Deposition (ALD) technology utilizing the Cambridge Nanotech Savannah 100 ALD system. Physical characterizations of film thickness, film morphology, and surface roughness of the deposited platinum were all performed before and after rapid thermal annealing (RTA) and as a function of forming gas annealing (FGA). Noble metal thin films of platinum were deposited on four inch wafers of p-type boron doped &100& oriented silicon (Si) substrates. The ALD film thickness was measured with a novel method utilizing the linear dependence …

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Optimizing The Performance Of White Light-Emitting Diodes For Energy-Efficient Lighting, Yiting Zhu Sep 2009

Optimizing The Performance Of White Light-Emitting Diodes For Energy-Efficient Lighting, Yiting Zhu

Link Foundation Energy Fellowship Reports

Over the past decade, high-brightness monochromatic (colored) LEDs have been replacing traditional incandescent light sources in certain niche applications such as traffic signals and “EXIT” signs. LEDs are able to save up to 80% energy and significantly reduce maintenance costs in these applications. A similar trend is expected in architectural, transportation and general illumination with white LEDs. Even though the efficiency and light output of white LEDs have been improving steadily, they still need to improve by twice as much and offer good color appearance before they achieve the target of 200 lumens per watt with high color quality, as …

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Energy-Efficient, Flow-Specific Medium Access Using Preamble Sampling, T. Owens Walker Iii, Murali Tummala, John Mceachen Sep 2009

Energy-Efficient, Flow-Specific Medium Access Using Preamble Sampling, T. Owens Walker Iii, Murali Tummala, John Mceachen

United States Navy: Publications

Current wireless sensor network applications face challenging power constraints that demand low duty cycles. In this paper, we propose an energy-efficient, flow-specific medium access scheme that is capable of achieving low duty cycles while taking advantage of the performance improvements available through a flow-specific medium access approach. The scheme is based on an adaptive sleep and wake cycle that responds to changes in both contention and non-contention traffic loads through the use of preamble sampling. A preamble sampling probability parameter is introduced to manage the trade-off between energy efficiency and network throughput and delay performance. A performance analysis is conducted …

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Power Consumption And Performance Analysis Of Object Tracking And Event Detection With Wireless Embedded Smart Cameras, Mauricio Casares, Alvaro Pinto, Youlu Wang, Senem Velipasalar Sep 2009

Power Consumption And Performance Analysis Of Object Tracking And Event Detection With Wireless Embedded Smart Cameras, Mauricio Casares, Alvaro Pinto, Youlu Wang, Senem Velipasalar

Department of Electrical and Computer Engineering: Faculty Publications

An embedded smart camera is a stand-alone unit that not only captures images, but also includes a processor, memory and communication interface. With battery-powered and embedded smart cameras, it has become viable to install many spatially-distributed cameras interconnected by wireless links. Not requiring to have access to electrical outlets and have wired links increase system flexibility. However, wireless and battery-powered smart-camera networks introduce many additional challenges since they have very limited resources, such as power, memory and bandwidth. The algorithms running on the camera boards should be lightweight and efficient. In addition, the frequency of communication between camera nodes, and …

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Power Efficiency Of Cooperative Communication In Wireless Sensor Networks, Sunita Gupta, Mehmet C. Vuran, M. Cenk Gursoy Sep 2009

Power Efficiency Of Cooperative Communication In Wireless Sensor Networks, Sunita Gupta, Mehmet C. Vuran, M. Cenk Gursoy

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, a new protocol termed CoopXLM that integrates cooperative communication and Cross-Layer Module (XLM) is created and examined via simulation. CoopXLM modifies XLM by allowing multiple cooperative nodes to participate in receiver-based contention. Although there is increased energy consumption for processing, simulation results indicate that across all duty cycles there is an average energy savings of 38% with CoopXLM in comparison to XLM. It was also found that CoopXLM yields higher goodput than XLM at lower duty cycles but yields lower goodput at higher duty cycles.

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Model For Virtual Physical Layer Communication Over Deployed Wireless Sensor Networks, Thomas Childers, Yow Thiam Poh, John Mceachen, Murali Tummala Sep 2009

Model For Virtual Physical Layer Communication Over Deployed Wireless Sensor Networks, Thomas Childers, Yow Thiam Poh, John Mceachen, Murali Tummala

United States Navy: Publications

A method for file transfer utilizing forward error correction (FEC) to pass traffic over deployed wireless sensor networks is studied. The entire wireless sensor network is modeled as an error-prone virtual physical link. Previous work in the area of terminal communication across the sensor network is expanded upon to include file transfer in order to provide a more capable channel and a basis for testing the performance obtained through erasure coding. The results of the FEC implementation are examined using multiple sensor network configurations. While the error correction method proved effective, larger topologies presented congestion issues due to the sensors’ …

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Methods For Cancer Detection, Kimberly W. Anderson, Kimberly M.L. May, Leonidas G. Bachas Sep 2009

Methods For Cancer Detection, Kimberly W. Anderson, Kimberly M.L. May, Leonidas G. Bachas

Chemical and Materials Engineering Faculty Patents

A method is provided for detecting an analyte indicative of a cancer or a metastatic disease condition, which utilizes the ability of the analyte to induce permeability in a barrier. The method includes providing a biosensor having a barrier which is substantially impermeable to an ion, a permeable membrane which is selective for the ion, and a detector capable of detecting the ion. The biosensor is contacted with a sample including at least one of the ion and the analyte, wherein the analyte causes at least a portion of the ion to pass through the barrier and the membrane. Passage …

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Assessment Of Climate Change Impacts On Water Resources Of The Upper Blue Nile River Basin, Ethiopia, U. Kim, Jagath J. Kaluarachchi Sep 2009

Assessment Of Climate Change Impacts On Water Resources Of The Upper Blue Nile River Basin, Ethiopia, U. Kim, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Climate change affects water resources availability of international river basins that are vulnerable to runoff variability of upstream countries especially with increasing water demands. The upper Blue Nile River Basin is a good example because its downstream countries, Sudan and Egypt, depend solely on Nile waters for their economic development. In this study, the impacts of climate change on both hydrology and water resources operations were analyzed using the outcomes of six different general circulation models (GCMs) for the 2050s. The outcomes of these six GCMs were weighted to provide average future changes. Hydrologic sensitivity, flow statistics, a drought index, …

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Power Quality Analysis Of Grid-Connected Photovoltaic System With Adjustable Speed Drives, M. Anwari, M. Imran Hamid, M.I. M. Rashid, Taufik Sep 2009

Power Quality Analysis Of Grid-Connected Photovoltaic System With Adjustable Speed Drives, M. Anwari, M. Imran Hamid, M.I. M. Rashid, Taufik

Electrical Engineering

This paper presents power quality analysis of a distributed generation system consisting of Photovoltaic (PV)-Inverter system as the renewable source connected to a network of Adjustable Speed Drives (ASDs) as the load. A small-scale laboratory consists of Photovoltaic, Inverter, ASDs and loads system was setup. Two power supplies from PV and grid were connected to two ASDs which powered two separate induction motors. Load of motor 1 was fixed while load of motor 2 was varied. In the experiment, both energy supplies from the grid and photovoltaic system were connected to the loads. Measurements have been done at both side …

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Tracking Rhythmicity In Biomedical Signals Using Sequential Monte Carlo Methods, Sungan Kim Sep 2009

Tracking Rhythmicity In Biomedical Signals Using Sequential Monte Carlo Methods, Sungan Kim

Dissertations and Theses

Cyclical patterns are common in signals that originate from natural systems such as the human body and man-made machinery. Often these cyclical patterns are not perfectly periodic. In that case, the signals are called pseudo-periodic or quasi-periodic and can be modeled as a sum of time-varying sinusoids, whose frequencies, phases, and amplitudes change slowly over time. Each time-varying sinusoid represents an individual rhythmical component, called a partial, that can be characterized by three parameters: frequency, phase, and amplitude. Quasi-periodic signals often contain multiple partials that are harmonically related. In that case, the frequencies of other partials become exact integer multiples …

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