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2015

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Sustainability Assessment For Energy Systems And Chemical Process Industries, Michael J. Matzen Dec 2015

Sustainability Assessment For Energy Systems And Chemical Process Industries, Michael J. Matzen

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Sustainability has become an important factor in the chemical process and energy industries with a strong drive for process improvements towards more environmentally conscious solutions. However, there are many ways of defining sustainability and even more ways of trying to determine how sustainable a process is. This work looks into applying a conjunction of tools including; process simulation, multi-criteria decision matrices and life-cycle assessment to more quantitatively determine sustainability metrics. We have applied these tools for the production of electricity, methanol and dimethyl ether. A novel method of electricity production, in chemical looping combustion (CLC), was used that inherently involves …

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Openline Newsletter, December 2015/January 2016, Civil Service Council Dec 2015

Openline Newsletter, December 2015/January 2016, Civil Service Council

OpenLine Newsletter

A monthly newsletter for Civil Service employees, December 2015/January 2016.

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Studying An All-Vanadium Photoelectrochemical Cell For Highly Efficient Solar Energy Conversion And Storage Via Photocatalytic Redox Reaction, Dong Liu Dec 2015

Studying An All-Vanadium Photoelectrochemical Cell For Highly Efficient Solar Energy Conversion And Storage Via Photocatalytic Redox Reaction, Dong Liu

Material Science and Engineering Dissertations - Archive

This study aims at developing a promising alternative approach to utilize solar energy continuously with high efficiency by employing photocatalytic vanadium redox reactions to overcome major drawbacks associated with conventional photoelectrochemical water splitting. The preliminary study was implemented on TiO2 and WO3/TiO2 by linear sweep voltammetry (LSV), cyclic voltammetry (CV) and zero-resistance ammetry (ZRA) in a photoelectrochemical cell (PEC). The results show much enhanced photoelectrochemical response with the assistance of vanadium(IV, VO2+) redox species. Such photoresponse improvement is attributed to the hole scavenging effect by fast vanadium redox reaction to depress charge recombination at semiconductor/liquid interface in both TiO2 and …

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Magnetic-Plasmonic Multilayered Nanorods, Orathai Thumthan Dec 2015

Magnetic-Plasmonic Multilayered Nanorods, Orathai Thumthan

Material Science and Engineering Dissertations - Archive

Multilayered nanorods which consist of alternating magnetic layers separated by Au layers combine two distinctive properties, magnetic properties and surface plasmonic resonance (SPR) properties into one nano-entity. Their magnetic properties are tunable by changing the layer thickness, varying from single domain to superparamagnetic state. Superparamagnetic is a key requirement for magnetic nanoparticles for bioapplications. Superparamagnetic nanoparticles exhibit high magnetic moments at low applied magnetic field while retain no magnetic moments when magnetic field is removed preventing them from aggregation due to magnetic attraction. Au layers in the nanorods provide anchorage sites for functional group attachment. Also, Au nanodisks exhibit SPR …

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Comprehensive Study Of Composition Gradient Strontium Doped Lanthanum Manganite Thin Films Deposited By Magnetron Co-Sputtering, Yishu Wang Dec 2015

Comprehensive Study Of Composition Gradient Strontium Doped Lanthanum Manganite Thin Films Deposited By Magnetron Co-Sputtering, Yishu Wang

Material Science and Engineering Dissertations - Archive

In this body of work, the examination of three different types of Strontium doped lanthanum manganite thin films synthesized by magnetron sputtering in the Surface and Nano Engineering Laboratory (SaNEL) allowed for the development of a detailed understanding between the processing conditions, the nano-scale structure and strain relaxation of the as-deposited thin films. Pure Lanthanum manganite and strontium doped lanthanum manganite thin films which were epitaxially grown on (001) single crystalline lanthanum alumina (LAO) and magnesium oxide (MgO) were fabricated by using single target deposition. The optimum deposition conditions were explored as preparation for synthesis epitaxial composition gradient strontium doped …

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Reactions Of The Transgender Community Regarding Media Representation, Chani Wellborn Dec 2015

Reactions Of The Transgender Community Regarding Media Representation, Chani Wellborn

Communication Theses - Archive

Lesbian, gay, bisexual, and transgender (LGBT) issues have increasingly been focused on in society and also in communication media research. However, academic studies focusing on transgender reactions to recent representation developments of their community in the media world have not been done. The researcher conducted one-on-one interviews with those identifying as male to female (MtF) transgender in order to study their reactions to media coverage of the transgender community. Cultural studies and communication theories, as well as transgender and trans-identity theories provided a theoretical structure and basis for developing the study and interview questions. Qualitative methodology using an inductive grounded …

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Guanidinium Based Anion Exchange Membranes For Solid Polymer Alkaline Fuel Cell Applications, Syed Dawar Sajjad Dec 2015

Guanidinium Based Anion Exchange Membranes For Solid Polymer Alkaline Fuel Cell Applications, Syed Dawar Sajjad

Material Science and Engineering Dissertations - Archive

Low temperature traditional PEM Fuel Cells and also other fuel cells in general suffer from the acute yet long standing issues of cost and performance. This has severely hindered the commercialization of fuel cells but Alkaline Anion Exchange Membrane Fuel Cells (AAEMFCs) pose as a breakthrough technology by offering improved conversion efficiency (a virtue of fast kinetics in the alkaline media) and the lower costs (from the prospect of using non-noble metal catalysts). However, before systematic testing of non-noble metal catalysis is tested on this system, it is imperative to develop a reliable anion exchange membrane which lies at the …

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Detecting Real-Time Check-Worthy Factual Claims In Tweets Related To U.S. Politics, Fatma Dogan Dec 2015

Detecting Real-Time Check-Worthy Factual Claims In Tweets Related To U.S. Politics, Fatma Dogan

Computer Science and Engineering Theses - Archive

In increasing democracy and improving political discourse, political fact-checking has come to be a necessity. While politicians make claims about facts all the time, journalists and fact-checkers oftentimes reveal them as false, exaggerated, or misleading. Use of technology and social media tools such as Facebook and Twitter has rapidly increased the spread of misinformation. Thus, human fact-checkers face difficulty in keeping up with a massive amount of claims, and falsehoods frequently outpace truths. All U.S. politicians have successively adopted Twitter, and they make use of Twitter for a wide variety of purposes, a great example being making claims to enhance …

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Qp-Subdue: Processing Queries Over Graph Databases, Ankur Goyal Dec 2015

Qp-Subdue: Processing Queries Over Graph Databases, Ankur Goyal

Computer Science and Engineering Theses - Archive

Graphs have become one of the preferred ways to store structured data for various applications such as social network graphs, complex molecular structure, etc. Proliferation of graph databases has resulted in a growing need for effective querying methods to retrieve desired information. Querying has been widely studied in relational databases where the query optimizer finds a sequence of query execution steps (or plans) for efficient execution of the given query. Until now, most of the work on graph databases has concentrated on mining. For querying graph databases, users have to either learn a graph query language for posing their queries …

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Lung Cancer Subtype Classification From Whole Slide Histopathological Images, Dheeraj Ganti Dec 2015

Lung Cancer Subtype Classification From Whole Slide Histopathological Images, Dheeraj Ganti

Computer Science and Engineering Theses - Archive

Lung Cancer is one of the most serious diseases causing death for human be- ings. The progression of the disease and response to treatment di ers widely among patients. Thus it is very important to classify the type of tumor and also able to predict the clinical outcomes of patients. Majority of lung cancers is Non-Small Cell Lung Cancer (NSCLC) which constitutes of 84 % of all the type of lung cancers. The two major subtypes of NSCLC are Adenocarcinoma (ADC) and Squamous Cell Car- cinoma (SCC). Accurate classi cation of the lung cancer as NSCLC and its subtype classi …

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Quantitative Analysis Of Scalable Nosql Databases, Surya Narayanan Swaminathan Dec 2015

Quantitative Analysis Of Scalable Nosql Databases, Surya Narayanan Swaminathan

Computer Science and Engineering Theses - Archive

NoSQL databases are rapidly becoming the customary data platform for big data applications. These databases are emerging as a gateway for more alternative approaches outside traditional relational databases and are characterized by efficient horizontal scalability, schema-less approach to data modeling, high performance data access, and limited querying capabilities. The lack of transactional semantics among NoSQL databases has made the application determine the choice of a particular con- sistency model. Therefore, it is essential to examine methodically, and in detail, the performance of different databases under different workload conditions. In this work, three of the most commonly used NoSQL databases: MongoDB, …

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Speaker Identification In Live Events Using Twitter, Minumol Joseph Dec 2015

Speaker Identification In Live Events Using Twitter, Minumol Joseph

Computer Science and Engineering Theses - Archive

The prevalence of social media has given rise to a new research area. Data from social media is now being used in research to gather deeper insights into many different fields. Twitter is one of the most popular microblogging websites. Users express themselves on a variety of different topics in 140 characters or less. Oftentimes, users “tweet” about issues and subjects that are gaining in popularity, a great example being politics. Any development in politics frequently results in a tweet of some form. The research which follows focuses on identifying a speaker’s name at a live event by collecting and …

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Interactive Dashboard For User Activity Using Network Flow Data, Lalit Kumar Naidu Dec 2015

Interactive Dashboard For User Activity Using Network Flow Data, Lalit Kumar Naidu

Computer Science and Engineering Theses - Archive

Data visualization is critical in analytical systems containing multi-dimensional dataset and problems associated with increasing data size. It facilitates the data explanation process of reasoning data and discovering trends with visual perception that are otherwise not evident within the data in its raw form. The challenge involved in visualization is presenting data in such a way that helps end users in the process of information discovery with simple visuals. Interactive visualizations have increasingly become popular in recent years with prominent research in the field of information visualization. These techniques are heavily used in web-based applications to present myriad forms of …

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Energy And Water Impacts Of Data Center Cooling Systems: A Triple Bottom Line Assessment For Facility Design, Marianna Louisa Vallejo Dec 2015

Energy And Water Impacts Of Data Center Cooling Systems: A Triple Bottom Line Assessment For Facility Design, Marianna Louisa Vallejo

Mechanical and Aerospace Engineering Dissertations - Archive

Increasingly, society is being transferred to a dependence upon electronic technologies and networked systems, usually accessed via the internet. Physically, these systems reside within clusters of servers and storage banks which are collectively housed and maintained in data center facilities. In order for a data center to function properly, the environment must be tightly controlled to ensure maximum reliability of the electronic hardware components. Any method of controlling the environment has a cost, either in capital or in resources, and therefore becomes an issue for the sustainability of a building or complex. Currently data centers are one of the largest …

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Material Changes Of Bone Following Ishcemia Of The Immature Femoral Head, Olumide O. Aruwajoye Dec 2015

Material Changes Of Bone Following Ishcemia Of The Immature Femoral Head, Olumide O. Aruwajoye

Mechanical and Aerospace Engineering Dissertations - Archive

Legg-Calvé-Perthes disease (LCPD) is a childhood hip disorder resulting from the loss of blood flow to the femoral head. In severe cases of the disease, the femoral head can develop a flattening deformity; additionally, if the disease is diagnosed at a later stage, it leaves most patients to develop early osteoarthritis of the hip. Due to a lack of pathological specimen from patients, an experimental piglet model of femoral head ischemia was developed. The model closely follows the radiographic changes seen in LCPD patients, where there is subchondral fracture, resorption, and a flattening deformity of the femoral head. After ischemia, …

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Development Of A Methodology And Sample Preparation To Evaluate Reliability Of Oil Cooled Data Center, Venkata Naga Indu Sravani Kota Dec 2015

Development Of A Methodology And Sample Preparation To Evaluate Reliability Of Oil Cooled Data Center, Venkata Naga Indu Sravani Kota

Mechanical and Aerospace Engineering Theses - Archive

Liquid immersion cooling is not a new concept which is slowly emerging as an alternative solution to conventional chilled air cooling systems for data centers. The main idea is to build a body of knowledge to help industry make more informed regarding mechanical reliability of IT equipment in mineral oil immersed systems. The goal is to develop a testing procedure for evaluating the reliability of electronic packages and components when immersed in mineral oil. PCB’s, chip packages, passive components like capacitors, inductors, resistors, diodes, cables and wiring form the most important parts of a server used in data centers. The …

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Neural Network Modeling And Control Of Data Center, Nachiket Rajendra Kansara Dec 2015

Neural Network Modeling And Control Of Data Center, Nachiket Rajendra Kansara

Mechanical and Aerospace Engineering Theses - Archive

Data Center has become a definitive element of Modern IT infrastructure. With the development of high performance computing architectures and equipment, data centers consume large amount of electricity. Due to low Demand/Supply ratio of electricity production there is need to develop ways to reduce power footprint. Many researchers are working on approaches to resolve problems related to en- ergy usage of Data Center. One of these approaches is to develop a model-based control system that would control data centers in efficient way to reduce power footprint. Computational Fluid Dynamic (CFD) has been used to model the dynamic and complex environment …

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Impact Of Layer Thickness Of Qfn Package Mounted Printed Circuit Boards During Drop Testing, Sayalee Pradeep Sabne Dec 2015

Impact Of Layer Thickness Of Qfn Package Mounted Printed Circuit Boards During Drop Testing, Sayalee Pradeep Sabne

Mechanical and Aerospace Engineering Theses - Archive

In past studies, it was established that board level reliability of the packages depends mainly upon the design of the package and the soldering technology used for mounting the components. There are many methods to test the reliability, such as temperature cycling test, bend test, power cycling, etc. which have been studied and practiced. We need to consider the failure rate and failure mechanism both, to understand how specific loading conditions affect the failure of an assembly. In this study, PCB’s with variable thicknesses and QFN package mountings are subjected to drop test. It has been observed previously that the …

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Fabrication And Characterization Of Low-Density Polymeric Materials With 3d Microstructures, Hakan Arslan Dec 2015

Fabrication And Characterization Of Low-Density Polymeric Materials With 3d Microstructures, Hakan Arslan

Mechanical and Aerospace Engineering Theses - Archive

Low-density polymeric materials with octet-truss and quad-truss 3D microstructures were studied. The materials with 3D microstructures were created using digital light processing technology with polyethylene glycol (PEG). The mechanical properties of the materials with different relative densities were characterized in air and water. The experimental results were also compared and analyzed with the results from simulation studies. This work reveals that the material with octet-truss microstructures stand at least three times higher deformation than the materials with quad-truss microstructures. The polymeric material with internal 3D microstructures also shows a higher water absorption rate than the same material without internal microstructures.

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Non Thermal Reliability Considerations For Oil Cooled Data Centers And Its Serviceability, Sahithi Reddy Nagilla Dec 2015

Non Thermal Reliability Considerations For Oil Cooled Data Centers And Its Serviceability, Sahithi Reddy Nagilla

Mechanical and Aerospace Engineering Theses - Archive

The interest in Oil immersion cooling is increasing day by day which can be attributed to the recent research that shows the potential of its performance when compared to other techniques that add a little more expenses to the organization. Even though the performance of oil immersion cooling has its own capabilities and advantages, this technique is not widely adopted and there is limited published information regarding the important aspects of the design of the system. This paper presents the non-thermal aspects of oil immersion cooling and explains the chemistry of mineral oil and the factors that affect its performance. …

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Quantitative Evaluation Of A Thrust Vector Controlled Transport At The Conceptual Design Phase, Vincent Patrick Ricketts Dec 2015

Quantitative Evaluation Of A Thrust Vector Controlled Transport At The Conceptual Design Phase, Vincent Patrick Ricketts

Mechanical and Aerospace Engineering Theses - Archive

The impetus to innovate, to push the bounds and break the molds of evolutionary design trends, often comes from competition but sometimes requires catalytic political legislature. For this research endeavor, the ‘catalyzing legislation’ comes in response to the rise in cost of fossil fuels and the request put forth by NASA on aircraft manufacturers to show reduced aircraft fuel consumption of +60% within 30 years. This necessitates that novel technologies be considered to achieve these values of improved performance. One such technology is thrust vector control (TVC). The beneficial characteristic of thrust vector control technology applied to the traditional tail-aft …

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Thermal Analysis Of Disk Brake In Order To Study The Brake Fluid Vaporization Phenomenon Of A Formula Sae Car, Anurag Dey Dec 2015

Thermal Analysis Of Disk Brake In Order To Study The Brake Fluid Vaporization Phenomenon Of A Formula Sae Car, Anurag Dey

Mechanical and Aerospace Engineering Theses - Archive

The brake system is inarguable one of the most critical aspect of a vehicle safety. It has always been the major concern for design engineers to develop a system that gives a steady performance with respect to time. In order to achieve that feat, one of the most common problems that arises in maintaining a brake is the problem of brake fluid vaporization. Brake fluids, being hygroscopic in nature, absorb moisture over a period of time. It is one of the prime reasons for reducing the longevity of brake fluid volume inside the brake caliper as the boiling point of …

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Automatic Carrier Landing System For V/Stol Aircraft Using L1 Adaptive And Optimal Control, Shashank Hariharapura Ramesh Dec 2015

Automatic Carrier Landing System For V/Stol Aircraft Using L1 Adaptive And Optimal Control, Shashank Hariharapura Ramesh

Mechanical and Aerospace Engineering Theses - Archive

This thesis presents a framework for developing automatic carrier landing systems for aircraft with vertical or short take-off and landing capability using two different control strategies - gain-scheduled linear optimal control, and L1 adaptive control. The carrier landing sequence of V/STOL aircraft involves large variations in dynamic pressure and aerodynamic coefficients arising because of the transition from aerodynamic-supported to jet-borne flight, descent to the touchdown altitude, and turns performed to align with the runway. Consequently, the dynamics of the aircraft exhibit a highly non-linear dynamical behavior with variations in flight conditions prior to touchdown. Therefore, the implication is the need …

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The Effect Of Temperature And Relative Humidity On The Corrosion Rates Of Copper And Silver In Electronic Equipment In The Presence Of Sulfur Environment, Kanan Pujara Dec 2015

The Effect Of Temperature And Relative Humidity On The Corrosion Rates Of Copper And Silver In Electronic Equipment In The Presence Of Sulfur Environment, Kanan Pujara

Mechanical and Aerospace Engineering Theses - Archive

Data center consume a significant amount of energy for the continuous air-conditioning of the servers with high internal heat loads and to maintain the indoor temperatures within recommended operating levels as recommended by ASHRAE. As an alternate source to air-conditioning, air-side economizers are used to reduce power consumption. However, there is a reluctance in using this technique due to undetermined equipment reliability by introducing outside air pollutants which over time could cause failures. There is a need to know the degree of reliability degradation when the equipment is operated, outside the recommended range, in the allowable temperature-humidity range in geographies …

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Additive Manufacturing And Stress Analysis Of Naturally And Artificially Optimized Celullar Structures, Sachin Jose Dec 2015

Additive Manufacturing And Stress Analysis Of Naturally And Artificially Optimized Celullar Structures, Sachin Jose

Mechanical and Aerospace Engineering Theses - Archive

The main objective of our research is to manufacture topology optimized cellular structures using 3D printing and polymer infusion and obtain their structural response. First, we have obtained topology optimized cellular structure of beam using an in-house topology optimization tool. The Solid Isotropic material with Penalization (SIMP) method of optimization is used for finding the optimal topology. Since we require a continuous structure where we can take advantage of additive manufacturing, a no-penalty approach was chosen. For 3D printing, first the optimized condition for manufacturing was determined. Important parameters on which manufacturing depend are Number of Shells, Infill percentage and …

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Experimental Analysis Validating A Control Scheme To Develop A Dynamic Cooling Solution For Non-Uniform High Powered Electronic Devices In Data Center, Ruturaj Kiran Kokate Dec 2015

Experimental Analysis Validating A Control Scheme To Develop A Dynamic Cooling Solution For Non-Uniform High Powered Electronic Devices In Data Center, Ruturaj Kiran Kokate

Mechanical and Aerospace Engineering Theses - Archive

The trend towards higher heat fluxes and non-uniform power distribution continues as we follow Moore’s law with technology nodes now approaching 10nm. Cooling is always designed for maximum junction temperature and as such it is important to mitigate hot spots. All cold plates have a static design by nature and do not possess the capability to respond to non-uniform heat dissipation. The unique “dynamic cold plate” concept aims to improving on conventional static designs through implementation of sensing and control, by redistributing the liquid across its body to counter varying power dissipation across the device being cooled.

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Smart Bed And Contact Impact Of Flexible Bodies Using Energy Compensation Method, Pranav Parikh Dec 2015

Smart Bed And Contact Impact Of Flexible Bodies Using Energy Compensation Method, Pranav Parikh

Mechanical and Aerospace Engineering Theses - Archive

This work investigates robotic means to prevent pressure ulcers in human bodies. The smart bed is intended to act as an intelligent assistant to a care-giver that relieves some of the physical and mental burden involved in preventing pressure ulcers. This type of device is needed because of a labor shortage in the nursing field. The smart bed distinguishes itself from the current available measures by redistributing pressure and minimizing shear forces acting on the skin in contact. This is done by using data from the sensor grid installed on the bed surface and actuating the degrees of freedom associated …

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Cfd Modeling And Parametric Study Of Vapor Chamber As Heat Spreaders For High-Power Electronic Devices, Dhanraj Arun Patil Dec 2015

Cfd Modeling And Parametric Study Of Vapor Chamber As Heat Spreaders For High-Power Electronic Devices, Dhanraj Arun Patil

Mechanical and Aerospace Engineering Theses - Archive

Technological developments have resulted in a growing demand for high power electronic devices. Although these high power devices meet the high performance requirements, they also generate a very large amount of heat which adversely affects their operating efficiency. Most part of the heat within a package is generated at the chip and hence it is imperative to keep junction temperature as low as possible. This is commonly achieved by using heat sinks mounted directly on top of the package. Heat sinks provide a significant enhancement in cooling by increasing the surface area. However, base thickness of heat sinks limits its …

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The Effect Of Material Strain Hardening On The Buckling Strength Of A Perforated Plate Under Uniaxial Loading, Mayuri Suresh Patil Dec 2015

The Effect Of Material Strain Hardening On The Buckling Strength Of A Perforated Plate Under Uniaxial Loading, Mayuri Suresh Patil

Mechanical and Aerospace Engineering Theses - Archive

Plates or members containing plate elements have been used in the offshore, aerospace and construction industry. Cutouts are often located to lighten the weight of the structure, but these cutouts reduce the ultimate strength of the plate. A number of studies have taken place for determining the buckling strength of a perforated plated but few discuss the effect of material strain hardening on the buckling strength of a perforated plate. Buckling strength is often considered as an important criterial to determine the serviceable limit of the perforated plate in the offshore structure. The aim of the present study is to …

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Estimation Of Fracture Mechanics Parameters In 3d Tsv Package During Chip Attachment Process, Mohammed Shahid Ali Dec 2015

Estimation Of Fracture Mechanics Parameters In 3d Tsv Package During Chip Attachment Process, Mohammed Shahid Ali

Mechanical and Aerospace Engineering Theses - Archive

Nowadays, the packaging of electronic products is becoming revolutionized, since the packages are becoming more and more complex, dense, thinner and lighter for greater portability. Miniaturization of packages is being taken to the next level, and hence, 3D packaging has become a hot topic in the present research area. Three dimensional chips stacking with TSV technology has gained momentum to meet such requirements of significant miniaturization and power reduction which result in increased performance. However, the unique issues related to yield and reliability of critical areas in TSV based 3D ICs need to be evaluated. Therefore, Reliability of such electronic …

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