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Computational Analysis Of Structure And Function Of Genomic Sequences, Abanish Singh Jan 2008

Computational Analysis Of Structure And Function Of Genomic Sequences, Abanish Singh

Computer Science and Engineering Dissertations - Archive

The genetic code consists of long chains of deoxyribonucleic acid (DNA) present in every cell of a living organism. These chains contain both functional and non-functional DNA sequences, and their proportion in the mix varies widely along the tree of life. Generally, more complex organisms tend to feature large amounts of "junk" DNA, whose importance is still subject of a debate in the scientific circles. The functional sequences include coding sequences (genes) and various types of signals, mostly, but not exclusively, controlling the regulation of coding sequences, i.e. activating and deactivating the expression of genes, during the developmental stage, in …

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Statistical Approach To The Development Of A Microscale Model For Estimating Exhaust Emissions Of Light Duty Gasoline Vehicles, Benjamin Nmai Afotey Jan 2008

Statistical Approach To The Development Of A Microscale Model For Estimating Exhaust Emissions Of Light Duty Gasoline Vehicles, Benjamin Nmai Afotey

Civil Engineering Dissertations - Archive

Today, air pollution is taking a growing toll on human health, the environment and the economy, despite decades of efforts to combat it. Although it was once a primary urban phenomenon in industrialized countries, today air pollution has spread worldwide. Mobile, industrial and natural sources constitute the major sources of air pollution. Around the world, major cities in industrialized countries have in recent times been battling air pollution from mobile sources. Beijing, New Delhi, Dallas/ Fort Worth and Los Angeles are no exceptions.Pronounced interest has focused on mobile source (vehicle exhaust) emissions in recent decades. A rapid increase in the …

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Multi-Criteria Assessment For Supporting Freeway Operations And Management Systems, Auttawit Upayokin Jan 2008

Multi-Criteria Assessment For Supporting Freeway Operations And Management Systems, Auttawit Upayokin

Civil Engineering Dissertations - Archive

Freeway traffic congestion represents an increasing concern for urban areas throughout the United States. In addition, faced with limited roadway expansion alternatives, transportation agencies are considering investment in traffic management centers (TMCs) as a more viable way to operate and manage freeways effectively. The TMCs' responsibilities include monitoring roadway conditions using the various data collection strategies and determining performance measures for freeway operations. At the same time, traffic engineers at the TMCs may react to the traffic congestion problems by implementing operational strategies. In order to provide reliable decision support for TMC freeway operations and management systems, this dissertation aims …

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Feasibility Study Of An Ultra Fast Gated Camera To Image Biliary Tree Embedded In Adipose Tissue Using Laboratory Phantoms And Monte Carlo Simulations, Nimit Lalitkumar Patel Jan 2008

Feasibility Study Of An Ultra Fast Gated Camera To Image Biliary Tree Embedded In Adipose Tissue Using Laboratory Phantoms And Monte Carlo Simulations, Nimit Lalitkumar Patel

Bioengineering Theses - Archive

Every year, approximately 500,000 cholecystectomies are performed in US. As biliary tree structures are embedded in adipose tissue, they cannot be visualized directly by the surgeon, which causes inadvertent injuries to the common bile duct, vein and artery during a laparoscopic cholecystectomy. Thus there is an urge for an imaging modality which could see biliary tree structure through fatty tissue. Successful clinical implementation of an imaging system which could attain this goal would reduce surgical time, improve patient safety and minimize the risk of complications and expenses attributable to the current standard practice of intraoperative cholecystectomy. It is hoped that …

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Automated Quantification Of White Matter Hyperintensity Burden Using Mprage And Flair Images From A Large Population, Keith Mcleod Hulsey Jan 2008

Automated Quantification Of White Matter Hyperintensity Burden Using Mprage And Flair Images From A Large Population, Keith Mcleod Hulsey

Bioengineering Theses - Archive

White Matter Hyperintensity(WMH) burden, as observed in T2 and proton weighted MR images, is associated with several health factors such as decreased cognitive ability, hypertension, diabetes and cerebrovascular disease. An algorithm was developed to automatically estimate WMH burden from pairs of MPRAGE and FLAIR images which is robust and requires essentially no operator involvement. The WMH burden estimation generated by this fully automated algorithm has been shown to correlate well with known risk factors for WMH burden.

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Synthesis And Characterisation Of Raman Nanotags For Molecular Detection, James Otieno Nyagilo Jan 2008

Synthesis And Characterisation Of Raman Nanotags For Molecular Detection, James Otieno Nyagilo

Bioengineering Theses - Archive

The realization that most diseases are preceded or accompanied by changes in the genetic and cellular level of an organism has increased with the need for imaging modalities, with the sensitivity and specificity, to quantitatively detect biomolecules at those levels. Specifically there has been a need for the development of a modality that has the ability to detect multiple biomolecules from a single sample in order to increase accuracy of molecular diagnosis and allow for early detection of terminal diseases. Surface enhanced Raman spectroscopy provides potential for such a modality. The distinct spectrum of each Raman active molecule serves as …

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Visible To Near Infra Red Hyperspectral Imaging: Visualizing The Neurological And Biological Nature Of Ischemic Tissue, Swetha Suresh Jan 2008

Visible To Near Infra Red Hyperspectral Imaging: Visualizing The Neurological And Biological Nature Of Ischemic Tissue, Swetha Suresh

Bioengineering Theses - Archive

Diabetic Neuropathy is a neuropathic disorder which is associated with Diabetes Mellitus. It is known to result in lower limb ulcers which can lead to amputation. Nerve damage, microvascular dysfunctions and use of ill fitting shoes are significant causes for it. These abnormal dysfunctions can lead to Ischemia. We have used the Multimodal Hyperspectral Imaging System image areas of high pressure on the skin that correspond to pain and also to visualize vascular changes that are associated with this pain. The instrument majorly consists of near-infrared and visible charge coupled devices (CCDs), lenses, liquid crystal tunable filters (LCTFs) for both …

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Development Of Optical Fiber Sensors For Distance, Refractive Index And Strain Measurement, Ayan Majumdar Jan 2008

Development Of Optical Fiber Sensors For Distance, Refractive Index And Strain Measurement, Ayan Majumdar

Mechanical and Aerospace Engineering Theses - Archive

This thesis is focused on the development of optical fiber based sensors for the measurement of distance, refractive index, and strain. The fabrication, implementation, analysis, and evaluation of the sensors are presented. The Extrinsic Fabry-Perot Interferometric (EFPI) distance sensor is one of the most popular distance sensors but it possesses an inherent drawback. When the free-space cavity distance is very small, the numbers of fringes generated are not sufficient for the distance demodulation algorithm; therefore the smallest distance it can measure is determined by the bandwidth of the light source. An optical fiber based distance sensor is developed in this …

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A Process For Ice Detector Placement Using 3-D Eulerian Droplet Impingement Analysis, Glenn T. Lancaster Jan 2008

A Process For Ice Detector Placement Using 3-D Eulerian Droplet Impingement Analysis, Glenn T. Lancaster

Mechanical and Aerospace Engineering Theses - Archive

Ice detectors invoke an aircraft's ice protection systems, which reduce the risks of flight into known icing conditions. A process has been developed to place ice detectors on aircraft using high fidelity computational icing tools. Three-dimensional Eulerian droplet impingement analysis is used to determine the necessary ice detector height and location required to achieve full functionality. This method is applied to the V-22 Osprey tiltrotor aircraft for validation against both tunnel and flight test data. When compared to icing tunnel test data, computational results for the volume of ice accreted on an antenna were within ten percent, validating the computational …

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Capacity Of Two-Sided Type C On Freeway With Four Lanes, Shadi Ghasemi-Majd Jan 2008

Capacity Of Two-Sided Type C On Freeway With Four Lanes, Shadi Ghasemi-Majd

Civil Engineering Theses - Archive

Weaving segments are categorized based on weaving length, configuration, number of lanes, free flow speed and weaving ratio. All these parameters affect weaving capacity. One of the objectives of this research was to extend Phong Thanh Vo's dissertation and study the relation between weaving capacity of two-sided type C on freeways with four lanes and any potential variables (mainalane demand, entrance ramp demand, exit ramp demand and weaving ratio). Micro-simulation has been used in order to analyze different capacity scenarios and the VISSIM calibrated model by Vo was used. Also, the effect of each of the VISSIM calibration parameters on …

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The Effect Of Displacement Control Loading Histories On Genral Connecting Surfaces Using Finite Element Analysis, Sanjog Chandrakant Sabnis Jan 2008

The Effect Of Displacement Control Loading Histories On Genral Connecting Surfaces Using Finite Element Analysis, Sanjog Chandrakant Sabnis

Civil Engineering Theses - Archive

Displacement loading history provided by the AISC Seismic Provision 2002 is commonly used for experimental testing and analytical modeling of beam-to-column steel connection to stimulate the seismic effect. However, the basis for the above loading history is not documented in the literature. Thus, this study developed 25 cyclic load cases by varying the frequency and magnitude of the AISC-2002 loading within a predefined envelops. The 25 load cases are obtained from five different load sets in which the concept of uniform and non-uniform frequencies and amplitude are utilized. All the load cases are limited to the displacement equivalent to the …

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Clay Mineral Quantification Using Gravemetric Analysis, Sarwenaj Ashraf Jan 2008

Clay Mineral Quantification Using Gravemetric Analysis, Sarwenaj Ashraf

Civil Engineering Theses - Archive

The current procedure used by the Texas Department of Transportation (TxDOT) to determine the type of stabilizer is based mainly on the Plasticity Index (PI) and the gradation of the soil. This method of stabilization does not always work because two soils with the same PIs can have very different shrink/swell potential, plastic limits or liquid limits, hence their behavior may be very different. This is mainly due to the fact that two soils that have the same PI can have very different clay mineral composition. Montmorillonite and kaolinite are the clay minerals that cause swelling/shrinking in soils.Chittoori (2008) had …

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Helmholtz's Theorem Based Parametric Non-Rigid Image Registration, Hsi-Yue S. Hsiao Jan 2008

Helmholtz's Theorem Based Parametric Non-Rigid Image Registration, Hsi-Yue S. Hsiao

Computer Science and Engineering Dissertations - Archive

Helmholtz's theorem states that, with suitable boundary condition, a vector field is completely determined if both of its divergence and curl are specified everywhere. Based on this, we developed a new parametric non-rigid image registration algorithm. Instead of the displacements of regular control grid points, the curl and divergence at each grid point are employed as the parameters. This leads to a very simple mathematical model - two Poisson equations in 2-D or three Poisson equations in 3-D which will be used to solve for the displacement field. The similarity measure is sum of squared difference. And multi-resolution is applied …

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The University Of Texas At Arlington Graduate Catalog 2008-2010, The University Of Texas At Arlington Jan 2008

The University Of Texas At Arlington Graduate Catalog 2008-2010, The University Of Texas At Arlington

UTA Graduate Catalogs

No abstract provided.

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Unmanned Aerial Vehicle Routing With Limited Risk, Siriwat Visoldilokpun Jan 2008

Unmanned Aerial Vehicle Routing With Limited Risk, Siriwat Visoldilokpun

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Due to safety and uninhabitable surrounding environments, long range Unmanned Aerial Vehicles (UAVs) have become an increasingly popular option in both scientific and military applications. With troubling oil prices, a logistic planner requires an efficient method to identify an optimal routing solution. The solution should not only optimize the bottom line objective but must also control variations in an operation.We study the UAV routing problem with limited risk (URPR) in which the considered risk is a fuel burn variance caused by wind variation. The URPR determines the optimal route that minimizes total expected fuel burn to visit all assigned targets …

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Combining The Wind Power Generation System With Energy Storage Equipments, Ming-Shun Lu Jan 2008

Combining The Wind Power Generation System With Energy Storage Equipments, Ming-Shun Lu

Electrical Engineering Theses - Archive

With the advance in wind turbine technologies, the cost of wind energy becomes competitive with other fuel-based generation resources. Due to the price hike of the fossil fuel and the concern of the global warming, the development of wind power has rapidly progressed over the last decade. The annual growth rate of the wind generation installation has exceeded 26% since 1990s. Many countries have set goal for high penetration levels of wind generations. Recently, several large-scale wind generation projects have been implemented all over the world. It is economically beneficial to integrate very large amounts of wind capacity in power …

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A Particle Filter Based Framework For Indoor Wireless Localization Using Custom Ieee 802.15.4 Nodes, Vijay Vasant Dixit Jan 2008

A Particle Filter Based Framework For Indoor Wireless Localization Using Custom Ieee 802.15.4 Nodes, Vijay Vasant Dixit

Computer Science and Engineering Theses - Archive

Locating people and objects as soon as possible and fair amount of precision has always been an important part of any organization or industry, especially in manufacturing, healthcare, and logistics. Systems that now have the ability to locate objects or people are called Real Time Location Systems (RTLS). They typically use small low-power transmitters called tags attached to assets (or worn by people) as well as sets of readers that map the location of these tags. Systems that map the longitude and attitude of an object are geo-location systems and generally use GPS for location mapping. Systems that map a …

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Dynacet: A Minimum-Effort Driven Dynamic Faceted Search System Over Structured Databases, Haidong Wang Jan 2008

Dynacet: A Minimum-Effort Driven Dynamic Faceted Search System Over Structured Databases, Haidong Wang

Computer Science and Engineering Theses - Archive

In this thesis, we propose minimum-effort driven navigational techniques for enterprise database systems based on the faceted search paradigm. Our proposed techniques dynamically suggest facets for drilling down into the database such that the cost of navigation is minimized. At every step, the system asks the user a question or a set of questions on different facets and depending on the user response, dynamically fetches the next most promising set of facets, and the process repeats. Facets are selected based on their ability to rapidly drill down to the most promising tuples, as well as on the ability of the …

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Modeling And Simulation Of A General Motors Conveyor System Using A Custom Decision Optimizer, Mirza Mohammad Lutfe Elahi Jan 2008

Modeling And Simulation Of A General Motors Conveyor System Using A Custom Decision Optimizer, Mirza Mohammad Lutfe Elahi

Computer Science and Engineering Theses - Archive

The temporal behavior of conveyor systems can be modeled using discrete event (DE) simulations. DE modeling provides a quick and cost effective method for analyzing complex problems as different scenarios can be tested rapidly without affecting the day to day activities of production systems. A simulation model coupled with decision optimization on routing choices enables the evaluation of different decision strategies.In the General Motors paint shop at Arlington, Texas, the complex conveyor system moving cars to the paint booths has been observed to mix up same color batches of cars coming from the body shop. At the paint booth, every …

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Hybrid Video Coding Design With Variable Size Integer Transforms And Structural Similarity, Att Kruafak Jan 2008

Hybrid Video Coding Design With Variable Size Integer Transforms And Structural Similarity, Att Kruafak

Electrical Engineering Dissertations - Archive

This research proposes a block-based video codec design with two objectives. The first goal is to propose a method for intraframe that improves the rate-distortion (peak signal-to-noise ratio versus bit rate) of a fixed-size transform encoder. The proposed method uses three integer transform sizes (4x4), (8x8), and (16x16). The codec also adopts H.264-like spatial prediction to intraframe encoding. For simplicity of the design, Huffman variable-length code is used as entropy encoding. For intraframe encoding, the simulations show rate-distortion improvement over JPEG and JPEG2000. In some test sequences, the simulations also show improvement over H.264 (baseline profile at low complexity mode …

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Complex Directional Wavelet Transforms: Representation, Statistical Modeling And Applications, An Phuoc Nhu Vo Jan 2008

Complex Directional Wavelet Transforms: Representation, Statistical Modeling And Applications, An Phuoc Nhu Vo

Electrical Engineering Dissertations - Archive

The thesis presents an new image decomposition for feature extraction, which is called the pyramidal dual-tree directional filter bank (PDTDFB). The image representation has an overcomplete ratio of less than 8/3 and uses a separable filter bank implementation structure. We discuss how to utilize both magnitude and phase information obtained from the PDTDFB for the purpose of texture image retrieval. The relative phase, which is the difference of phases between two adjacent complex coefficients, has a linear relationship with the angle of dominant orientation within a subband. This information is incorporated to form a new feature vector called CDFB-RP. Another …

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Data Mining-Driven Approahces For Process Monitoring And Diagnosis, Thuntee Sukchotrat Jan 2008

Data Mining-Driven Approahces For Process Monitoring And Diagnosis, Thuntee Sukchotrat

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

The objective of this dissertation is to develop a new set of efficient process monitoring and diagnostic tools through their integration with data mining algorithms. Statistical process control (SPC) is one of the most widely used techniques for quality control. Although traditional SPC tools are effective in simple manufacturing processes that generate a small volume of independent data, these tools falter when confronted by the large streams of complex and correlated data found in modern manufacturing systems. As the limitations of SPC methodology become increasingly obvious in the face of ever more complex manufacturing processes, data mining, because of its …

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Use Of Wireless Signal Characteristics For Mobile Robotics Localization And Access Point Mapping, Joshua Davies Jan 2008

Use Of Wireless Signal Characteristics For Mobile Robotics Localization And Access Point Mapping, Joshua Davies

Computer Science and Engineering Theses - Archive

Mobile robotics is an interesting and challenging emerging field in computer science.To properly achieve true autonomy, a robot must be able to determine where it is in relationshipto a global frame of reference and it must be able to do so with a minimum of interaction fromhuman operators and impose as few constraints on its surroundings as possible. The uncertainnature of mobility and perception requires that advanced probabilistic inference techniques beapplied to minimize error. This work examines the applicability of radio-frequency signals to the mobile robotlocalization problem to localize quickly over a wide area. Particle filtering techniques areemployed to adjust …

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The Thermal Effects Of Self Heating Of Transistors On Analog Amplifier Design And Evaluation, Kamal Ranjan Sinha Jan 2008

The Thermal Effects Of Self Heating Of Transistors On Analog Amplifier Design And Evaluation, Kamal Ranjan Sinha

Electrical Engineering Dissertations - Archive

Electrothermal effects play a major role in the performance of modern silicon-on-insulator (SOI) bipolar junction transistors (BJTs). This research work examines the influence of electrothermal feedback within a single device and within a circuit composed of such devices. Specifically, the frequency-domain thermal effects of self-heating in SOI BJTs on the performance of analog integrated circuits, with emphasis on current mirrors, and current-feedback operational amplifiers (CFOA), are investigated through analytical formulation, simulation, and measurement.For the extensive analysis and characterization of self-heating thermal effects, the Vertical Bipolar Inter-Company (VBIC) models for SOI BJTs are developed from fundamental physical device considerations. Extensive simulations …

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Thermal Characterization Of Dielectrically Isolated Bipolar Junction Transistor, Daewoo Kim Jan 2008

Thermal Characterization Of Dielectrically Isolated Bipolar Junction Transistor, Daewoo Kim

Electrical Engineering Dissertations - Archive

Since the integrated circuit (IC) was invented in 1960, the operating speed of semiconductor devices has steadily increased and the number of semiconductor devices in an IC chip has grown by a size reduction of the devices. This trend has lead to the rapid increase of power consumption and heat generation. As a result of this increase, thermal characterization of semiconductor devices has become more important.It is especially important to consider thermal characteristics of the dielectrically isolated complementary bipolar junction transistor (DIBJT) which offers many advantages. However, a major disadvantage of this device is an increase in self-heating. Because the …

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Functional Data Analysis For Environmental And Biomedical Problems, Chivalai Temiyasathit Jan 2008

Functional Data Analysis For Environmental And Biomedical Problems, Chivalai Temiyasathit

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Vast amounts of data are being generated due to the development of sensing technology. Among those, one of the common types of data usually found in various discipline is the functional data. Because the functional data are generally collected in a wide area of interest over a relatively long period, such analyses should take into account both temporal and spatial characteristics. Furthermore, combinations of observations from multiple locations, each with a large number of serially correlated values, lead to a situation that poses a great challenge to analytical and computational capabilities. In contrast, data obtained from medical and biomedical researches …

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Towards An Implementation Of Avoip: Anonymous Voice-Over-Ip, Bikas Raj Gurung Jan 2008

Towards An Implementation Of Avoip: Anonymous Voice-Over-Ip, Bikas Raj Gurung

Computer Science and Engineering Theses - Archive

Voice over IP (VoIP) is one of the fastest growing telecommunicaiton market today. However with great popularity comes greater security risk. When we communicate over the Internet we expose our identity to all the prying eyes, even if we do not want to. Even though VoIP data can be secured by using encryption, sometimes the relationships between users can be sensitive. To provide stronger privacy for these users, we propose anonymous VoIP (aVoIP) - a means to secure user privacy in VoIP. The biggest challenge in introducing anonymity to VoIP system is in providing acceptable Quality of Service (QoS). Users …

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Temporal Potential Function Approach For Path Planning In Dynamic Environments, Vamsikrishna Gopikrishna Jan 2008

Temporal Potential Function Approach For Path Planning In Dynamic Environments, Vamsikrishna Gopikrishna

Computer Science and Engineering Theses - Archive

A Dynamic environment is one in which either the obstacles or the goal or both are in motion. In most of the current research, robots attempting to navigate in dynamic environments use reactive systems. Although reactive systems have the advantage of fast execution and low overheads, the tradeoff is in performance in terms of the path optimality. Often, the robot ends up tracking the goal, thus following the path taken by the goal, and deviates from this strategy only to avoid a collision with an obstacle it may encounter. In a path planner, the path from the start to the …

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Adapting Harmonic Function Path Planning: To Reflect User Motion Preferences, Giles John D'Silva Jan 2008

Adapting Harmonic Function Path Planning: To Reflect User Motion Preferences, Giles John D'Silva

Computer Science and Engineering Theses - Archive

Every human in the real world has a unique motion preference while moving to achieve a given task. These preferences could be expressed by moving in a straight line, following the wall along a corridor, avoiding sharp turns, preferring hard flat surfaces over damp uneven surfaces, choosing the shortest path to the goal or by giving a high priority towards safety by maintaining a definite distance from obstacles. To automatically incorporate user preferences into motion planning we could extract the trajectories taken by the user to achieve a task in a given local vironment and attempt to use them in …

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Thermal Effects And Analysis On Analog Integrated Circuit Design, Ardasheir Sayek Rahman Jan 2008

Thermal Effects And Analysis On Analog Integrated Circuit Design, Ardasheir Sayek Rahman

Electrical Engineering Theses - Archive

Analog circuit design is an art of circuit designing. With technology becoming more advance and size of devices shrinking, circuit designing has becoming a real chance for the designers to meet up the demands in the market. Density of device transistor is rapidly increasing leading to thermal runaway issues and increasing operational speed of the transistors. Thus transistors are more sensitive to temperature changes, therefore requiring a more sensitive and accurate modeling of the thermal effects of the device as well as its adjacent devices. This research is on the thermal modeling of dielectric bipolar junction devices. It looks into …

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