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Articles 2341 - 2370 of 3180

Full-Text Articles in Engineering

Silicon Wafer Defect Segmentation Using Modified Pulse Coupled Neural Network, Chaitanya Telidevara Jan 2011

Silicon Wafer Defect Segmentation Using Modified Pulse Coupled Neural Network, Chaitanya Telidevara

Electrical Engineering Theses - Archive

Defect segmentation has been a focal point in silicon wafer inspection research and it remains challenging because the defects are complicated by large variations in intensity distribution. An algorithm for silicon wafer defect segmentation is developed using a modified pulse coupled neural network (PCNN). The modified PCNN is simple version of the PCNN in which segmentation depends only on the linking coefficient and initial threshold. The initial threshold and linking coefficient are determined automatically from image statistics using method described in [17] and Otsu's method respectively. The modified PCNN method was found to be simple and efficient for silicon wafer …

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Design And Development Of A General Purpose Embedded Acquisition System For Transportation Applications, Akshay Avinash Joshi Jan 2011

Design And Development Of A General Purpose Embedded Acquisition System For Transportation Applications, Akshay Avinash Joshi

Electrical Engineering Theses - Archive

The Texas Department of Transportation (TxDOT) uses many different instruments for quality assurance of new and existing pavements. These instruments measure the different characteristics of the pavement such as the longitudinal profile, transverse profile, texture, rut formation etc to determine the smoothness and ride quality of the pavement. These instruments mainly consist of different sensors such as a laser, an accelerometer and/or a gyroscope to calculate the ride quality. Different ride statistics like the International Roughness Index (IRI), Mean Profile Depth (MPD), Present Serviceability Index (PSI) are then calculated andused to determine the need for repair of the pavements. Currently …

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Wlan Based Indoor Localization, Sreejith Sisupalan Lathikumari Jan 2011

Wlan Based Indoor Localization, Sreejith Sisupalan Lathikumari

Electrical Engineering Theses - Archive

Localization based on received signal strength has been a topic of Interest due to its relative simplicity in measurement and minimal hardware requirements. Much of the research in this field has been on developing an indoor propagation model. A generic indoor propagation model has largely been unsuccessful due to the complex multipath environment present in indoor environments. The main focus of this study is to find the position of the target when the estimated distance from the measurement points are known. The straightforward approach to this problem is by using trilateration techniques. A novel weighted centroid based method is introduced …

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Pilot Based Channel Estimation For 3gpp Lte Downlink, Ankit Ashok Agarwal Jan 2011

Pilot Based Channel Estimation For 3gpp Lte Downlink, Ankit Ashok Agarwal

Electrical Engineering Theses - Archive

Channel estimation is an important part for the design of receivers in mobile communication systems. In order to recover the transmitted information correctly, the effect of the channel on the transmitted signal must be correctly estimated. In this thesis, the pilot based channel estimation algorithms for 3GPP LTE downlink is studied. Channel estimation algorithms such as Least Square (LS), Minimum Mean Square Error (MMSE) and Modified MMSE (M-MMSE) channel estimation algorithm have been evaluated for LTE downlink 5 MHz bandwidth configuration. The performance of these algorithms for Block type and Comb type pilot arrangement has been measured in terms of …

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Second Order Training Algorithms For Radial Basis Function Neural Networks, Kanishka Tyagi Jan 2011

Second Order Training Algorithms For Radial Basis Function Neural Networks, Kanishka Tyagi

Electrical Engineering Theses - Archive

A systematic two step batch approach for constructing and training of Radial basis function (RBF) neural networks is presented. Unlike other RBF learning algorithms, the proposed paradigm uses optimal learning factors (OLF's) to train the network parameters, i.e. spread parameters, mean vector parameters and weighted distance measure (DM) coefficients. Newton's algorithm is proposed for obtaining multiple optimal learning factors (MOLF) for the network parameters. The weights connected to the output layer are trained by a supervised-learning algorithm based on orthogonal least squares (OLS). The error obtained is then back-propagated to tune the RBF parameters. The proposed hybrid training algorithm has …

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A Planar And Integrated Rectenna For Wireless Power Reception, Vinay Ramachanndra Gowda Jan 2011

A Planar And Integrated Rectenna For Wireless Power Reception, Vinay Ramachanndra Gowda

Electrical Engineering Theses - Archive

In this thesis, a rectenna ("rectifier + antenna") for wireless power reception is designed and experimentally verified. The rectenna consists of two major components: one is a microstrip patch antenna and the other is a half-wave rectifier circuit. The microstrip antenna collects wireless power, and then, the received radio-frequency power is rectified to DC by the rectifier. The microstrip antenna and the rectifier circuit are simulated, fabricated, and tested separately. Before they are integrated, matching network is designed in between them to match the first harmonic. A few integrated rectenna's are built around 2.4 GHz ISM band. The rectenna's are …

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Behavioural Analysis Of Thermal Actuator Made Up Of Metals Like Titanium, Stainless Steel And Brass, Praveen Balaji Thangamani Balasubramanian Jan 2011

Behavioural Analysis Of Thermal Actuator Made Up Of Metals Like Titanium, Stainless Steel And Brass, Praveen Balaji Thangamani Balasubramanian

Electrical Engineering Theses - Archive

Out of the various MEMS actuators, thermal actuators are easy to realize and creates more force by consuming less power compared with other types of MEMS based actuators [2]-[4].Conventional thermal actuators are made up of poly silicon which requires the use of costlier equipment's for its fabrication and further it has to go through dark room processing which is time consuming. In our system the thermal actuator are made up of metals like titanium, stainless steel and brass which were fabricated using a programmable 5-W 355-nm laser system, which makes the fabrication process cheaper and less time consuming. Performance of …

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Organic Biocompatible Nanolayered Polymerization Of Solid-State Devices, Sri Divya Vidyala Jan 2011

Organic Biocompatible Nanolayered Polymerization Of Solid-State Devices, Sri Divya Vidyala

Bioengineering Theses - Archive

Nanotechnology plays a major role in today's society due to its convergence of nanoscale which is the level of atoms and molecules as a part of miniaturization trend. The interference between biomedical and nanotechnology are of intense research. It concerns about the utilization of miniature biological systems such as nucleic acids, proteins, cells and cellular components to fabricate functional organic and inorganic nanostructures. This research work focuses on the process of developing a simple method to obtain fluorinated organic nanocoating which can be used to coat 3D structures and also explain the extended applications of the coating in the fields …

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Substrate Stiffness Adjustable Pdms Device/Array For Understanding Its Effect On Cell Growth, Differentiation And Migration, Chetan Bhuwania Jan 2011

Substrate Stiffness Adjustable Pdms Device/Array For Understanding Its Effect On Cell Growth, Differentiation And Migration, Chetan Bhuwania

Bioengineering Theses - Archive

The mechanical properties of the cellular environment play an important role in the functioning of the cell. Cells attach to the extracellular matrix or other surrounding cells, thus sensing their mechanical properties and tune their own internal mechanical properties accordingly. A number of in vitro studies have been performed to study various cellular mechanical phenomena, but most of them employ a very stiff substrate such as glass or plastic that does not encompass the physiologically relevant range. Also, for tissues of the nervous system, the relationship between the substrate stiffness and the cellular behavior is less understood. In this study, …

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Diagnosis Of Breast Cancer Using Auto-Flourescence Lifetime And Light Reflectance Spectroscopy: A Potential Tool For Positive Margin Assessment, Shivaranjani Shivalingaiah Jan 2011

Diagnosis Of Breast Cancer Using Auto-Flourescence Lifetime And Light Reflectance Spectroscopy: A Potential Tool For Positive Margin Assessment, Shivaranjani Shivalingaiah

Bioengineering Theses - Archive

Malignant Breast Neoplasm (MBN) or breast cancer is a heterogeneous cancer type originating in the breast tissue. Surgery is considered the primary treatment for breast cancer, with many early stage patients being cured without recurrence. The goals of the surgery include complete resection of the primary tumor, with negative margins to reduce the risk of local recurrences. Further, pathological staging of the tumor and axillary lymph nodes are carried out to extract necessary prognostic information. Surgery works well in case of complete Mastectomies. However, the biggest challenge for this technique is determining adequate margins on the partial mastectomy (lumpectomy) specimen. …

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A Viscoelastic Model For Human Prolapsed Vaginal Wall Tissue, Milton Ma Jan 2011

A Viscoelastic Model For Human Prolapsed Vaginal Wall Tissue, Milton Ma

Bioengineering Theses - Archive

Pelvic organ prolapse (POP) affects thousands of elderly women each year. Improvements in surgical repair could benefit from the understanding of the biomechanical properties of the vaginal wall (VW) tissues to better tailor the needed repair. VW tissue property has been measured by uniaxial tensile test on excised fresh human anterior VW tissues. Data available, however, are limited to elastic modulus obtained in vitro. Recently, in vivo biomechanical data of VW from POP patients have been obtained by adapting a cutometer-like device, the BTC-2000TM (SRLI). The Voigt and Standard Linear models in conjunction with the framework of quasi-linear viscoelasticity theory …

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3-Dimensional Scanning And Reconstruction Using A Modified Hrt-Rcm Corneal Confocal Microscope, Saurabh Vaidya Jan 2011

3-Dimensional Scanning And Reconstruction Using A Modified Hrt-Rcm Corneal Confocal Microscope, Saurabh Vaidya

Bioengineering Theses - Archive

The HRT II - Rostock Corneal Module (HRT II-RCM) provides excellent resolution, contrast and optical sectioning capability for cornea imaging. It offers the most detailed views of cornea structure and pathology. However, the major limitation of this microscope is its scanning method. It has a threaded dial on the front side of the microscope which is coupled to the objective, and this dial has to be rotated manually to change the focal plane and to scan through the cornea.The dial is within inches of the cornea. During the scans, manual control causes serious interference and degrades the quality of the …

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Optimization Of Hydrogel System For Complex Wound Healing, Nikhil Vilas Aphale Jan 2011

Optimization Of Hydrogel System For Complex Wound Healing, Nikhil Vilas Aphale

Bioengineering Theses - Archive

Various conventional therapies and preventive measures have been developed and used for treating complex wounds; however, patients with complex wounds still develop wound infection and consist of delayed wound healing. These limitations necessitate the development of a novel therapeutic system, which is cost effective, easily apply onto the complex wounds, and consists of an efficient therapeutic nature. An in situ forming hydrogel system, made up of a novel biodegradable elastomer poly (ethylene glycol) maleate citrate (PEGMC), was designed and optimized for complex wound healing. Biocompatibility of this hydrogel system was studied by determining the toxicity of both the formation factors, …

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Process Modeling System For Press Cure, Closed-Cavity Tooled Thick Composites, Arven H. Saunders Jan 2011

Process Modeling System For Press Cure, Closed-Cavity Tooled Thick Composites, Arven H. Saunders

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Thick structural composite parts often use press curing with closed-cavity tooling for achieving dimensional tolerances. A commonly encountered defect for these parts is fiber waviness, whick limits its structural strength. The yield for such parts often suffers due to trial and error methods used to develop successful cure processes. In addition, yield for these parts suffers due to material variation. The objectives of this research were to: develop and validate a simplified yet practical cure process model for press cured thick composite parts, utilize the model in order to seek time-efficient optimized cure processes, investigate the effects of material variation …

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Control Of Airship Motion In The Presence Of Wind, Jatuporn Nakpiam Jan 2011

Control Of Airship Motion In The Presence Of Wind, Jatuporn Nakpiam

Mechanical and Aerospace Engineering Theses - Archive

This research effort develops a guidance and control system for a small airship to fly through assigned waypoints in the three dimensional space with a desired speed in the presence of wind and wind gust. In the control system development and validation, a simulation environment based on the nonlinear 6-DOF model of an airship, including the effect of the wind, is used. The airship has five control variables, the main thrust, the main thrust angle, the tail thrust, elevator and rudder deflections. The effectiveness of the elevator and rudder degrades as the speed of the airship decreases. The controller design …

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Development Of Multimodal Imaging System Combined With Laser Microbeam For Nanoscale Manipulation And Characterization., Ninad Ingle Jan 2011

Development Of Multimodal Imaging System Combined With Laser Microbeam For Nanoscale Manipulation And Characterization., Ninad Ingle

Material Science and Engineering Theses - Archive

Optical microscopy has fascinated biologists for probing and observing cellular structure while performing scientific research. While numerous wide-field and scanning microscopic techniques are being developed for probing cellular structure and function with high spatial and temporal resolution, mapping of complete biochemical, material and structural properties of the cell in three dimensions requires integration of multiple microscopic imaging techniques. In this thesis, conventional phase contrast microscopy and epifluorescence microscopy techniques were combined with other imaging methods such as digital holography microscopy (DHM) also known as quantitative phase microscopy, atomic force microscopy (AFM), near-field scanning optical microscopy (NSOM), total internal reflection fluorescence …

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Evaluation Of Resistivity Imaging (Ri) Method For Determining Unknown Deep Foundation Depth, Mohammad Sadik Khan Jan 2011

Evaluation Of Resistivity Imaging (Ri) Method For Determining Unknown Deep Foundation Depth, Mohammad Sadik Khan

Civil Engineering Theses - Archive

There are approximately 580,000 highway bridges in the National Bridge inventory and 104,000 of these bridges are estimated to have unknown foundations type and/or depth. Determining unknown foundation length and type of bridge foundation is becoming an important issue for State DOTs to ensure the safety of the bridge. There are several methods available to determine unknown foundation depth based on specific site conditions and type of foundation to be tested. Resistivity Imaging (RI) is a non destructive method to investigate the subsurface condition. The objective of current study was to determine unknown bridge foundation depth of three bridges at …

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Carbon Footprint Analysis Of A Large Diameter Water Transmission Pipeline Installation, Lalit Chilana Jan 2011

Carbon Footprint Analysis Of A Large Diameter Water Transmission Pipeline Installation, Lalit Chilana

Civil Engineering Theses - Archive

The term pipeline refers to a long line of connected segments of pipe, with pumps, valves, control devices, and other equipment or facilities needed for operating the system. Water transmission pipelines are generally large diameter (more than 12 in.) pipes which transport the water from one place to another. Installation of these pipes is a complex process due to variability of ground conditions over long distance installations. Sometimes, it is difficult to relate pipelines to the environment because of the out of sight nature. But it follows a close relationship with our environment due to various energy consuming activities involved …

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Experimental Investigation Of The Behavior Of The Steel Reinforced High Density Polyethylene And Corrugated Metal Pipe, Safa Sadat Masajedian Jan 2011

Experimental Investigation Of The Behavior Of The Steel Reinforced High Density Polyethylene And Corrugated Metal Pipe, Safa Sadat Masajedian

Civil Engineering Theses - Archive

Steel reinforced high density polyethylene pipes are gaining popularity these days because of their good performance and advantages of them in comparison to the other pipe materials. By inverting the steel ribs vertically in to the HDPE materials, strength of steel and flexibility and light weight of HDPE materials have been combined. However due the limited study in this area, the failure modes and design parameters are not classified.This study investigates the behavior and failure modes of SR-HDPE pipes under the simulated soil load and compares the results with the data obtained from the test on corrugated metal pipe under …

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Evaluation Of Building Information Modeling Applications For Small Construction Companies, Agustin Villafana Jan 2011

Evaluation Of Building Information Modeling Applications For Small Construction Companies, Agustin Villafana

Civil Engineering Theses - Archive

This thesis concerns developing recommendations to help small construction company's transition from traditional two dimensional plans to a Building Information Modeling (BIM) management process. Due to the cost of implementing BIM, the primary focus of the thesis is onthe transitioning state of these two management areas in an effort to facilitate full integration of smaller contractors into BIM technologies at a future time.Three case studies are used to assess and evaluate the effects of building information modeling on the schedule, material procurement, and information modeling aspects of a project. The intent of the case studies is to demonstrate a net …

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An Overview Of Mitigation Strategies For Settlements Under Bridge Approach Slabs, Raja Veerendra Yenigalla Jan 2011

An Overview Of Mitigation Strategies For Settlements Under Bridge Approach Slabs, Raja Veerendra Yenigalla

Civil Engineering Theses - Archive

Settlement and heave related movements of bridge approach slabs relative to bridge decks create a bump in the roadway causing inconvenience to the travelling public and at times so large as to make travelling unsafe. Hence, it is important to adopt suitable remedial methods to mitigate the approach settlements so as to ensure safe traveling conditions and also to decrease the repair/maintenance costs. This thesis presents an overview of a few case studies on different mitigation techniques applied on bridge approach settlement problems at various locations in the state of Texas. The methods employed to mitigate the settlement including Polyurethane …

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Use Of Steel Fiber Reinforced Concrete In Structural Members With Highly Complex Stress Fields, Tarun Pareek Jan 2011

Use Of Steel Fiber Reinforced Concrete In Structural Members With Highly Complex Stress Fields, Tarun Pareek

Civil Engineering Theses - Archive

Reinforced concrete (RC) members with significant geometric discontinuities and complex stress distributions under loading require considerable analyses and usually complicated reinforcement detailing. RC members with large openings are one of the examples. These large openings may interrupt the load transfer by direct concrete struts and cause substantial decrease in strength and unpredictable failure modes. The reinforcement detailing of these concrete members based on strut-and-tie models (STMs) is generally complicated and very often, these models cannot predict the failure mechanism due to localized damages. The actual stress fields in such members are typically very different from that predicated by STMs, as …

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The Effects Of A Variable Modulus Of Elasticity On Prestress Losses In Bridge Girders, Brahama Prakashni Singh Jan 2011

The Effects Of A Variable Modulus Of Elasticity On Prestress Losses In Bridge Girders, Brahama Prakashni Singh

Civil Engineering Theses - Archive

The purpose of this research is to evaluate a method proposed by Franz Dischinger (Dischinger, 1939) to consider the effects of a variable modulus of elasticity (MOE) of concrete over a period of time. Current guidelines suggested by the American Association of State Highways and Transportation Officials (AASHTO) assume a constant value for the MOE and base its calculation on the unit weight of concrete and the twenty eight day compressive strength of concrete. A few methods such as the ACI 209 Model Code (ACI 209, 1982) and CEB-FIP 1990 (CEB-FIP 1990, 1990) provide guidelines for the calculation of a …

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Targeted Nanoparticles For Cancer Therapy: Promises And Challenge, Kytai Truong Nguyen Jan 2011

Targeted Nanoparticles For Cancer Therapy: Promises And Challenge, Kytai Truong Nguyen

Bioengineering Faculty Publications - Archive

No abstract provided.

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Implementation Of Complexity Reduction Algorithm For Intra Mode Selection In H.264/Avc, Santosh Kumar Muniyappa Jan 2011

Implementation Of Complexity Reduction Algorithm For Intra Mode Selection In H.264/Avc, Santosh Kumar Muniyappa

Electrical Engineering Theses - Archive

For applications with low computational capabilities like handheld devices, it is necessary that the encoding complexity is minimal. But H.264, which is the most widely accepted video platform employs several powerful coding techniques that increase encoding complexity. Hence, the objective of this thesis is to implement an algorithm which reduces the encoding complexity by about 25%, but retains the quality of the existing intra prediction algorithm. H.264 offers nine modes for intra prediction of 4x4 luminance blocks, which includes DC prediction and eight directional modes (N4). For regions with less spatial detail, H.264 supports 16x16 intra coding, where in one …

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Low Complexity Avs-M Using Machine Learning Algorithm C4.5, Pragnesh Ramolia Jan 2011

Low Complexity Avs-M Using Machine Learning Algorithm C4.5, Pragnesh Ramolia

Electrical Engineering Theses - Archive

AVS China is the latest video coding standard developed by the AVS work group of China employing the latest video coding tools for achieving high compression while preserving the quality of the video [15]. AVS China video standard has been proven superior to the existing video standards such as MPEG-2 and MPEG-4 part 2, in terms of reduced complexity and coding efficiency. AVS is a set of integrated standard system which contains systems, video, audio and media copyright management. AVS-M, the 7th part of the system is video codec targeting mobile devices. AVS-M uses high efficiency tools like macroblock portioning, …

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Estimation Of Thermal Impedance Parameters Of Silicon Germanium Heterojunction Bipolar Transistors, Arun Thomas Karingada Jan 2011

Estimation Of Thermal Impedance Parameters Of Silicon Germanium Heterojunction Bipolar Transistors, Arun Thomas Karingada

Electrical Engineering Theses - Archive

Silicon Germanium (SiGe) hetero junction bipolar transistors (HBTs) are used in a variety of circuits like analog mixed signal and RF(radio frequency ) circuits. As the device gets smaller these days the self heating affects the performance of the SiGe HBTs. This paper uses theoretical methods based on device geometry and material properties to calculate the thermal resistance and thermal capacitance of SiGe HBT. In addition to theoretical estimations time domain, frequency domain and DC measurements are done on National Semiconductor's CBC8 HBTs which is used to extract the values of thermal impedance parameters.

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Optimal Path Planning, Implementation And Simulation For A Breast Biopsy System, Sridhar Rajaram Jan 2011

Optimal Path Planning, Implementation And Simulation For A Breast Biopsy System, Sridhar Rajaram

Electrical Engineering Theses - Archive

Core needle biopsy is a non-invasive method of confirming the presence of cancer cells in the breast. Image guided breast biopsy is a procedure performed to extract suspicious tissue and test it under the microscope for cancer. Common imaging modalities used are X-ray, MRI and Ultrasound. X-rays and MRI involve ionizing radiation which is harmful when a patient is suspected to have cancer. Apart from this, patients go through much discomfort during biopsy. Sometimes, multiple incisions are required to extract the desired tissue which prolongs the discomfort.This thesis describes a breast biopsy system using Ultrasound images. The main aim of …

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An Identifier-Tracking Based Model Reference Adaptive Control Without The Knowledge Of Relative Degree, Xiao Hu Jan 2011

An Identifier-Tracking Based Model Reference Adaptive Control Without The Knowledge Of Relative Degree, Xiao Hu

Electrical Engineering Dissertations - Archive

The purpose of Model Reference Adaptive Control (MRAC) is to create a controller with adjustable parameters to obtain the desired response from a reference model. One of the basic assumptions in MRAC is that the relative degree of the plant is known exactly. However, this assumption is too restrictive for some practical plants, since the relative degree of the plant may not be specified in advance. The study of MRAC with unknown relative degree has been important from both theoretical and practical point of view. This dissertation focuses on a new design approach for the model reference adaptive control of …

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Mixed Integer Programming Models For Selecting Ground-Level Ozone Control Strategies, Wei-Che Hsu Jan 2011

Mixed Integer Programming Models For Selecting Ground-Level Ozone Control Strategies, Wei-Che Hsu

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Under the Clean Air Act (CAA) in 1990, the U.S Environmental Protection Agency (EPA) was required to set National Ambient Air Quality Standards (NAAQS) for six common air pollutants that are considered harmful to public health and the environment. Ground–level ozone was one of the six criteria pollutants monitored by the EPA and considered the most widespread health threat. Two precursors of ground level ozone are nitrogen oxides (NOx) and volatile organic compounds (VOC) and the common sources of these two precursors include on–road vehicles, non–road engines, area sources, point sources, and biogenic and miscellaneous sources. An area …

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