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2011

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Articles 3961 - 3990 of 5801

Full-Text Articles in Engineering

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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Infrared-Based Measurements Of Velocity, Turbulent Kinetic Energy, And Dissipation At The Water Surface In A Tidal River, C. Chris Chickadel, Stefan A. Talke, Alexander R. Horner-Devine, Andrew T. Jessup Jan 2011

Infrared-Based Measurements Of Velocity, Turbulent Kinetic Energy, And Dissipation At The Water Surface In A Tidal River, C. Chris Chickadel, Stefan A. Talke, Alexander R. Horner-Devine, Andrew T. Jessup

Civil and Environmental Engineering Faculty Publications and Presentations

Thermal infrared (IR) based particle image velocimetry (PIV) is used to measure the evolution of velocity, turbulent kinetic energy (TKE), and the TKE dissipation rate at the water surface in the tidally influenced Snohomish River. Patterns of temperature variability in the IR imagery arise from disruption of the cool skin layer and are used to estimate the 2D velocity field. Comparisons of IR based PIV mean velocity made against a collocated acoustic velocimeter demonstrate high correlation (r2 > 0.9). Over a tidal period, surface TKE computed from the IR velocity varies from 10-4 J·kg-1 to 3x10-3 J·kg-1, with an average difference …

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Key Factors Affecting The Accuracy Of Reidentification Of Trucks Over Long Distances Based On Axle Measurement Data, Mecit Cetin, Christopher Monsere, Andrew Nichols, Ilyas Ustun Jan 2011

Key Factors Affecting The Accuracy Of Reidentification Of Trucks Over Long Distances Based On Axle Measurement Data, Mecit Cetin, Christopher Monsere, Andrew Nichols, Ilyas Ustun

Civil and Environmental Engineering Faculty Publications and Presentations

Vehicle reidentification methods can be used to anonymously match vehicles crossing two locations based on vehicle attribute data. This paper investigates key factors that affect the accuracy of vehicle reidentification algorithms. The analyses are performed with reidentification algorithms to match commercial vehicles that cross upstream and down-stream pairs of weigh-in-motion (WIM) sites that are separated by long distances, ranging from 70 to 214 mi. The data to support this research come from 17 fixed WIM sites in Oregon. Data from 14 pairs of WIM sites are used to evaluate how various factors affect matching accuracy; factors include the distance between …

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Multi-Sensor Optimization Of The Simultaneous Turning And Boring Operation, Erick Johan Deane Jan 2011

Multi-Sensor Optimization Of The Simultaneous Turning And Boring Operation, Erick Johan Deane

Electronic Theses and Dissertations

To remain competitive in today’s demanding economy, there is an increasing demand for improved productivity and scrap reduction in manufacturing. Traditional manufacturing metal removal processes such as turning and boring are still one of the most used techniques for fabricating metal products. Although the essential metal removal process is the same, new advances in technology have led to improvements in the monitoring of the process allowing for reduction of power consumption, tool wear, and total cost of production. Replacing used CNC lathes from the 1980’s in a manufacturing facility may prove costly, thus finding a method to modernize the lathes …

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Reduction Of Vibration Transmission In String Trimmers, Paurakh Rajbhandary, Jack Leifer, Bryan J. Weems Jan 2011

Reduction Of Vibration Transmission In String Trimmers, Paurakh Rajbhandary, Jack Leifer, Bryan J. Weems

Engineering Faculty Research

It has been well documented that over long periods of time, people who regularly operate hand tools powered by small internal-combustion engines can become affected by a debilitating set of clinically irreversible effects, collectively referred to as hand-arm vibration syndrome (HAVS). Although HAVS cannot be cured, the onset of the disorder can be delayed or, in fact, prevented, by restricting either the duration of the exposure, and/or the magnitude of the vibration transmitted from the tool to an operator's hands and arms (per ANSI and similar standards). In this paper, we’ve evaluated an approach for reducing the magnitude of transmitted …

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The Sensitivity Of Land Emissivity Estimates From Amsr-E As C And X Bands To Surface Properties, Hamid Norouzi, Marouane Temimi, William B. Rossow, Cindy Pearl, M. Azarderakhsh, Reza Khanbilvardi Jan 2011

The Sensitivity Of Land Emissivity Estimates From Amsr-E As C And X Bands To Surface Properties, Hamid Norouzi, Marouane Temimi, William B. Rossow, Cindy Pearl, M. Azarderakhsh, Reza Khanbilvardi

Publications and Research

Microwave observations at low frequencies exhibit more sensitivity to surface and subsurface properties with little interference from the atmosphere. The objective of this study is to develop a global land emissivity product using passive microwave observations from the Advanced Microwave Scanning Radiometer – Earth Observing System (AMSR-E) and to investigate its sensitivity to land surface properties. The developed product complements existing land emissivity products from SSM/I and AMSU by adding land emissivity estimates at two lower frequencies, 6.9 and 10.65 GHz (C- and X-band, respectively). Observations at these low frequencies penetrate deeper into the soil layer. Ancillary data used in …

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Lyapunov-Based Control Design For Uncertain Mimo Systems, Zhao Wang Jan 2011

Lyapunov-Based Control Design For Uncertain Mimo Systems, Zhao Wang

Electronic Theses and Dissertations

In this dissertation. we document the progress in the control design for a class of MIMO nonlinear uncertain system from five papers. In the first part, we address the problem of adaptive control design for a class of multi-input multi-output (MIMO) nonlinear systems. A Lypaunov based singularity free control law, which compensates for parametric uncertainty in both the drift vector and the input gain matrix, is proposed under the mild assumption that the signs of the leading minors of the control input gain matrix are known. Lyapunov analysis shows global uniform ultimate boundedness (GUUB) result for the tracking error under …

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Integration Of High-Q Filters With Highly Efficient Antennas, Yazid Yusuf Jan 2011

Integration Of High-Q Filters With Highly Efficient Antennas, Yazid Yusuf

Electronic Theses and Dissertations

The integration of high-quality (Q)-factor 3-D filters with highly efficient antennas is addressed in this dissertation. Integration of filters and antennas into inseparable units eliminates the transitions between the otherwise separate structures resulting in more compact and efficient systems. The compact, highly efficient integrated 3-D filter/antenna systems, enabled by the techniques developed herein, allow for the realization of integrated RF front ends with significantly- reduced form factors. Integration of cavity filters with slot antennas in a single planar substrate is first demonstrated. Due to the high Q factor of cavity resonators, the efficiency of the integrated filter/antenna system is found …

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Environmental Study Of Solid Waste Collection, Mousa Awad Maimoun Jan 2011

Environmental Study Of Solid Waste Collection, Mousa Awad Maimoun

Electronic Theses and Dissertations

The growing municipal solid waste generation rates have necessitated more efficient, optimized waste collection facilities. The majority of the US collection fleet is composed of diesel-fueled vehicles which contribute significant atmospheric emissions including greenhouse gases. In order to reduce emissions to the atmosphere, more collection agencies are investigating alternative fuel technologies such as natural gas, biofuels (bio-gas and bio-diesel), and hybrid electric technology. This research is an in-depth environmental analysis of potential alternative fuel technologies for waste collection vehicles. This study will evaluate the use of alternative fuels by waste collection vehicles. Lifecycle emissions, cost, fuel and energy consumption were …

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Design Of The Layout Of A Manufacturing Facility With A Closed Loop Conveyor With Shortcuts Using Queueing Theory And Genetic Algorithms, Vernet Michael Lasrado Jan 2011

Design Of The Layout Of A Manufacturing Facility With A Closed Loop Conveyor With Shortcuts Using Queueing Theory And Genetic Algorithms, Vernet Michael Lasrado

Electronic Theses and Dissertations

With the ongoing technology battles and price wars in today's competitive economy, every company is looking for an advantage over its peers. A particular choice of facility layout can have a significant impact on the ability of a company to maintain lower operational expenses under uncertain economic conditions. It is known that systems with less congestion have lower operational costs. Traditionally, manufacturing facility layout problem methods aim at minimizing the total distance traveled, the material handling cost, or the time in the system (based on distance traveled at a specific speed). The proposed methodology solves the looped layout design problem …

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Study Of High Efficiency Micro Thermoelectric Energy Harvesters, Steven Michael Pedrosa Jan 2011

Study Of High Efficiency Micro Thermoelectric Energy Harvesters, Steven Michael Pedrosa

Electronic Theses and Dissertations

Thermal energy sources, including waste heat and thermal radiation from the sun, are important renewable energy resources. Thermal energy can be converted into electricity by thermoelectric phenomena; the thermoelectric phenomena can also be operated in reverse when provided an electric current, producing a temperature gradient across the device. Thermoelectric devices are scalable, renewable, and cost effective products that offer capabilities to harness waste heat or environmental heat sources, and convert the captured heat into usable electricity. The operating principle of a thermoelectric device requires that a temperature gradient be present across the device, which induces the flow of electrons from …

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Exploring Techniques For Measurement And Improvement Of Data Quality With Application To Determination Of The Last Known Position (Lkp) In Search And Rescue (Sar) Data, Abhijit Wakchaure Jan 2011

Exploring Techniques For Measurement And Improvement Of Data Quality With Application To Determination Of The Last Known Position (Lkp) In Search And Rescue (Sar) Data, Abhijit Wakchaure

Electronic Theses and Dissertations

There is a tremendous volume of data being generated in today’s world. As organizations around the globe realize the increased importance of their data as being a valuable asset in gaining a competitive edge in a fast-paced and a dynamic business world, more and more attention is being paid to the quality of the data. Advances in the fields of data mining, predictive modeling, text mining, web mining, business intelligence, health care analytics, etc. all depend on clean, accurate data. That one cannot effectively mine data, which is dirty, comes as no surprise. This research is an exploratory study of …

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A Model To Integrate Sustainability Into The User-Centered Design Process, Adrienne Shevonne Brown Jan 2011

A Model To Integrate Sustainability Into The User-Centered Design Process, Adrienne Shevonne Brown

Electronic Theses and Dissertations

With concerns for the environment becoming more prevalent in business and the government, it is increasingly important to re-evaluate and update processes to include sustainability considerations early in the design process. In response to this charge, this research effort was designed to integrate sustainability factors into the usercentered design process. The results of this research highlight the benefits of sustainability requirement planning, as well as those derived from integrating sustainability into the current user-centered design model

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Analysis Of Behaviors In Crowd Videos, Ramin Mehran Jan 2011

Analysis Of Behaviors In Crowd Videos, Ramin Mehran

Electronic Theses and Dissertations

In this dissertation, we address the problem of discovery and representation of group activity of humans and objects in a variety of scenarios, commonly encountered in vision applications. The overarching goal is to devise a discriminative representation of human motion in social settings, which captures a wide variety of human activities observable in video sequences. Such motion emerges from the collective behavior of individuals and their interactions and is a significant source of information typically employed for applications such as event detection, behavior recognition, and activity recognition. We present new representations of human group motion for static cameras, and propose …

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Spectrum Sharing And Service Pricing In Dynamic Spectrum Access Networks, Swastik Kumar Brahma Jan 2011

Spectrum Sharing And Service Pricing In Dynamic Spectrum Access Networks, Swastik Kumar Brahma

Electronic Theses and Dissertations

Traditionally, radio spectrum has been statically allocated to wireless service providers (WSPs). Regulators, like FCC, give wireless service providers exclusive long term licenses for using specific range of frequencies in particular geographic areas. Moreover, restrictions are imposed on the technologies to be used and the services to be provided. The lack of flexibility in static spectrum allocation constrains the ability to make use of new technologies and the ability to redeploy the spectrum to higher valued uses, thereby resulting in inefficient spectrum utilization [23, 38, 42, 62, 67]. These limitations have motivated a paradigm shift from static spectrum allocation towards …

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Finite Depth Seepage Below Flat Apron With End Cutoffs And A Downstream Step, Arun K. Jain Jan 2011

Finite Depth Seepage Below Flat Apron With End Cutoffs And A Downstream Step, Arun K. Jain

Electronic Theses and Dissertations

Hydraulic structures with water level differences between upstream and downstream are subjected to seepage in foundation soils. Two sources of weakness are to be guarded against: (1) percolation or seepage may cause under-mining, resulting in the collapse of the whole structure, and (2) the floor of the apron may be forced upwards, owing to the upward pressure of water seeping through pervious soil under the structure. Many earlier failures of hydraulic structures have been reported due to these two reasons. The curves and charts prepared by Khosla, Bose, and Taylor still form the basis for the determination of uplift pressure …

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A Framework For Quantifying Sustainability Of Lean Implementation In Healthcare Organizations, Haitham Ahmed Bahaitham Jan 2011

A Framework For Quantifying Sustainability Of Lean Implementation In Healthcare Organizations, Haitham Ahmed Bahaitham

Electronic Theses and Dissertations

Due to the remarkable positive effect of lean adoption in various firms in the manufacturing sector, it has been adopted by several organizations within the healthcare industry. Although the rate of adopting lean by hospitals in the developed countries is slower than it should be, it proved to be effective in helping healthcare organizations maintain or even improve their quality of care while containing their related costs. However, such adoption did not take place until the beginning of the new millennium. And with such adoption, it has been accompanied with major challenges related to proper lean implementation, sustainability of achieved …

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Landfill Gas To Energy Incentives And Benefits, Hamid R. Amini Jan 2011

Landfill Gas To Energy Incentives And Benefits, Hamid R. Amini

Electronic Theses and Dissertations

Municipal solid waste (MSW) management strategies typically include a combination of three approaches, recycling, combustion, and landfill disposal. In the US approximately 54% of the generated MSW was landfilled in 2008, mainly because of its simplicity and cost-effectiveness. However, landfills remain a major concern due to potential landfill gas (LFG) emissions, generated from the chemical and biological processes occurring in the disposed waste. The main components of LFG are methane (50-60%) and carbon dioxide (40-50%). Although LFG poses a threat to the environment, if managed properly it is a valuable energy resource due to the methane content. Currently there are …

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