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2016

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The Influence Of The Interaction Of Carbon Based Materials With Ionic Liquid On The Tribological Performance Of Lubricating Grease And Oil, Kimaya Vyavhare Dec 2016

The Influence Of The Interaction Of Carbon Based Materials With Ionic Liquid On The Tribological Performance Of Lubricating Grease And Oil, Kimaya Vyavhare

Material Science and Engineering Theses - Archive

Stringent government regulation on environment emissions and demand to develop energy efficient and durable modern mechanical systems has imposed a significant challenge on the lubricant additive manufacturer to develop environment friendly and high performance additives for the lubricating medias like oil and grease. The current industrial additive technology is dominated by phosphorus and sulfur containing the liquid antiwear additive, Zinc dialkyl dithiophosphate and extreme pressure solid additives like Graphite, Molybdenum disulfide. This current additive package possesses harm to the environment and has already met performance limit for applications working under severe operating condition. A proposed solution to combat with this …

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Towards Artificial Proprioception In The Mandibular Full Arch Fixed Implant Prosthesis, Md Abu Hasan Dec 2016

Towards Artificial Proprioception In The Mandibular Full Arch Fixed Implant Prosthesis, Md Abu Hasan

Mechanical and Aerospace Engineering Dissertations - Archive

Full arch fixed implant prosthesis has been one of the most effective treatment modalities for fully edentulous patients over the last few decades. However, due to lack of proprioception occlusal overload is experienced by the prosthesis and its components causing major biomechanical complications such as screw/abutment fracture, framework fracture, and bone loss. The currently available approaches for the overload management rely on external appliances such as an occlusal splint or bite guard and result in occlusal discomfort and high patient dissatisfaction. In this research, an approach to induce artificial proprioception in the full arch fixed implant prosthesis is proposed. However, …

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A Novel Approach For Fabrication Of Single Silicon/Silicon Oxide Nanopillars At Precise Locations, Sravan Chowdary Talasila Dec 2016

A Novel Approach For Fabrication Of Single Silicon/Silicon Oxide Nanopillars At Precise Locations, Sravan Chowdary Talasila

Material Science and Engineering Theses - Archive

Nanopillars exhibit novel electrical and optical properties which could not be obtained from bulk materials. Many of their practical applications would require controlled placement of nanopillars at exact locations. However, precise placement and large scale fabrication of nanopillars have been challenging with conventional fabrication techniques. This thesis investigates a new approach to fabricate nanopillars at exact locations on a large scale. In this approach, fabrication of nanopillars is accomplished by first placing nanoparticles (NP) at exact locations and then performing anisotropic dry etching using these NPs as hard masks, resulting in formation of nanopillars on exact substrate positions. Precise placement …

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A Framework For Employing Femtosatellites In Planetary Science Missions, Including A Proposed Mission Concept For Titan, Tracie Renea Conn Perez Dec 2016

A Framework For Employing Femtosatellites In Planetary Science Missions, Including A Proposed Mission Concept For Titan, Tracie Renea Conn Perez

Mechanical and Aerospace Engineering Dissertations - Archive

Over the past 15 years, there has been a growing interest in femtosatellites, a class of tiny satellites having mass less than 100 grams. Research groups from Peru, Spain, England, Canada, and the United States have proposed femtosat designs and novel mission concepts for them. In fact, Peru made history in 2013 by releasing the first – and still only – femtosat tracked from LEO. However, femtosatellite applications in interplanetary missions have yet to be explored in detail. An interesting operations concept would be for a space probe to release numerous femtosatellites into orbit around a planetary object of interest, …

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Pilot Demonstration Based Reinforcement Learning With Application To Low Speed Airship Control, Onur Daskiran Dec 2016

Pilot Demonstration Based Reinforcement Learning With Application To Low Speed Airship Control, Onur Daskiran

Mechanical and Aerospace Engineering Dissertations - Archive

Designing control systems for airship has unique challenges as compared to conventional aircraft. Highly nonlinear dynamics, different mass/inertia relations, vast uncertainties in the model parameters and underactuation are the main reasons behind this. Airship dynamics is greatly influenced by the variations in the environmental (e.g.,room temperature) and internal (e.g., helium distribution in envelope) factors that can completely change the response characteristics of the blimp and make it infeasible for a model-based controller to perform. On the other hand, a skilled RC pilot can operate the manual flight easily under these conditions. This makes LfD (learning from demonstration) and RL (reinforcement …

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A Stochastic Distributed Control Allocation Method Using Probability Collectives, Christopher Michael Elliot Dec 2016

A Stochastic Distributed Control Allocation Method Using Probability Collectives, Christopher Michael Elliot

Mechanical and Aerospace Engineering Dissertations - Archive

The configuration of the aerospace vehicle of tomorrow marches forward in complexity in step with technological advances in computation, materials, propulsion, and beyond. One of many attributes resulting from this evolution is the multiple effector concept, replacing the traditional aircraft design approach of a dedicated four channel mixer where pitch-roll-yaw-speed is controlled by elevator-aileron-rudder-engine, respectively. Instead, for example on the propulsion front, a distributed suite of smaller engines can substitute the larger power plant and can be used in concert for multiple axis control with both simultaneous, collective thrust for force generation and differential cyclic thrust for moment generation. The …

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System Health Monitoring Using Multiple-Model Adaptive Estimation Techniques, Stanley Ryan Sifford Dec 2016

System Health Monitoring Using Multiple-Model Adaptive Estimation Techniques, Stanley Ryan Sifford

Mechanical and Aerospace Engineering Dissertations - Archive

Monitoring system health for fault detection and diagnosis by tracking system parameters concurrently with state estimates is approached using a new multiple-model adaptive estimation (MMAE) method. This novel method is called GRid-based Adaptive Parameter Estimation (GRAPE). GRAPE expands existing MMAE methods by using new techniques to sample the parameter space. GRAPE expands on MMAE with the hypothesis that sample models can be applied and resampled without relying on a predefined set of models. GRAPE is initially implemented in a linear framework using Kalman filter models. A more generalized GRAPE formulation is presented using extended Kalman filter (EKF) models to represent …

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Numerical Modeling Of Capillary Driven Microfluidic Flow, Md Ashraful Islam Dec 2016

Numerical Modeling Of Capillary Driven Microfluidic Flow, Md Ashraful Islam

Mechanical and Aerospace Engineering Dissertations - Archive

Capillary driven two dimensional axisymmetric and three dimensional asymmetric flow in various microfluidic applications have been modeled and analyzed numerically. The transient Navier-Stokes equations are solved using a finite-difference formulation with a two-step projection method on a fixed grid. The vapor-liquid interface of the micro-droplet is tracked by volume-of-fluid (VOF) and coupled level set and volume-of-fluid (CLSVOF) methods with the surface tension force determined by the continuum surface force (CSF) model. The static contact angle at the three phase contact line has been modeled using wall adhesion scheme within the CSF framework. The developed numerical method for capturing the microfluidic …

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Optimization Of Water And Energy Use In Indirect Evaporative Cooling System By Cfd, Mansi Vijay Prajapati Dec 2016

Optimization Of Water And Energy Use In Indirect Evaporative Cooling System By Cfd, Mansi Vijay Prajapati

Mechanical and Aerospace Engineering Theses - Archive

Data center cooling is becoming important to maintain environmental condition for ITE- Information technology equipment. Conventional evaporative wet cooling media lowers the temperature of the dry bulb temperature of incoming air in which heat transfer to water film and sensibly cool the product air by increasing moisture into air. Wet cooling media technique requires large quantity of clean water, which is reducing area where water is very less. Therefore, indirect evaporative cooling is good alternative. Chiller plants/Indirect Evaporative cooling(IEC) are used as a cooling source for larger data centers as they are more efficient in heat transfer without adding moisture …

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Self-Propulsion Of Liquid Drops Between Non-Parallel Structures At Leidenfrost State, Manjarik Mrinal Dec 2016

Self-Propulsion Of Liquid Drops Between Non-Parallel Structures At Leidenfrost State, Manjarik Mrinal

Mechanical and Aerospace Engineering Theses - Archive

In this work, we explored self-propulsion of a liquid drop between non-parallel structures at a temperature above its Leidenfrost point. A theoretical model was first developed to determine conditions for a drop to move away from the corner of two non-parallel plates. Subsequently, these results were validated by experiments. Finally, in Leidenfrost states, both lyophilic and lyophobic drops were shown to have the same dimensional movements away from the corner of two non-parallel plates.

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Effect Of Pcb Thickness On Solder Joint Reliability Of Qfn Package Under Power And Thermal Cycling, Srinivas Rahul Rao Dec 2016

Effect Of Pcb Thickness On Solder Joint Reliability Of Qfn Package Under Power And Thermal Cycling, Srinivas Rahul Rao

Mechanical and Aerospace Engineering Theses - Archive

Failure analysis and its effects are major reliability concerns in electronic packaging. More accurate fatigue life prediction can be obtained after the consideration of all affecting loads on the electronic devices. When an electronic device is turned off and then turned on multiple times, it creates a loading condition called power cycling. The die is the only heat source causing non-uniform temperature distribution. The solder joint reliability assessment of Quad Flat no-lead Package (QFN) is done through computational method i.e. Finite element analysis (FEA) under two different loads. In this paper, the power cycling and thermal cycling act as a …

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Finite Element Modeling And Stress Distribution Of Unidirectional Composite Materials Under Transversal Loading, Pavan Agarwal Dec 2016

Finite Element Modeling And Stress Distribution Of Unidirectional Composite Materials Under Transversal Loading, Pavan Agarwal

Mechanical and Aerospace Engineering Theses - Archive

Micromechanics of Composites analyze stresses inside any heterogeneous material. These stresses can not only be used for calculation of effective stiffness or compliance, but also for predicting strength and failure modes for these materials. This thesis is devoted to the stress analysis of unidirectional composites by finite element method. The key distinction from other finite element method modeling of the unidirectional composite was that the load on the cell was not prescribed, but was to be calculated taking into account the influence of the closest neighbors of the cell. Transversal unidirectional tension/compression and transversally symmetrical biaxial tension/compression were analyzed. In …

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Non-Invasive Measurement Of The Internal Temperature Of Heat-Generating Bodies, Dean Raymond Anthony Dec 2016

Non-Invasive Measurement Of The Internal Temperature Of Heat-Generating Bodies, Dean Raymond Anthony

Mechanical and Aerospace Engineering Theses - Archive

While the surface temperature of a heat-generating solid body can be measured using a variety of methods, there is a scarcity of techniques that exist for non-invasively measuring the temperature inside the solid body. Internal temperature measurement is very desirable as mere measurement of surface temperature gives no indication of the internal temperature. The highest temperature, usually located at the core of the body, dictates system performance and safety. For example, Li-ion cells provide good energy storage and conversion characteristics, but unfortunately suffer from safety problems related to overheating due to insufficient heat removal during operation. The following thesis presents …

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Remote Patient Monitoring Using Health Bands With Activity Level Prescription, Pranay Shirolkar Dec 2016

Remote Patient Monitoring Using Health Bands With Activity Level Prescription, Pranay Shirolkar

Mechanical and Aerospace Engineering Theses - Archive

With the advent of new commercially available consumer grade fitness and health devices, it is now possible and very common for users to obtain, store, share and learn about some of their important physiological metrics such as steps taken, heart rate, quality of sleep and skin temperature. For devices with this wearable technology, it is common to find these sensors embedded in a smart watch, or dedicated wearable wrist bands such that among other functionalities of a wearable device, it is capable of smartly assisting users about their activity levels by leveraging the fact that these devices can be, and …

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Evaluation Of Water Consumption And Savings Achieved In Datacenters Through Air Side Economization, Ravi Mishra Dec 2016

Evaluation Of Water Consumption And Savings Achieved In Datacenters Through Air Side Economization, Ravi Mishra

Mechanical and Aerospace Engineering Theses - Archive

Recent researches and a few facility owners have focused on eliminating the chiller plant altogether by implementing ‘Evaporative Cooling’, as an alternative or augmentation to compressor-based air conditioning since the energy consumption is dominated by the compressor work (around 41%) in the chiller plant. Because evaporative cooling systems consume water, when evaluating the energy savings potential of these systems, it is imperative to consider not just their impacts on electricity use, but also their impacts on water consumption as well since Joe Kava, Google’s head of data center operations, was quoted as saying that water is the “big elephant in …

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Design Optimization Of Pressure Vessel With Particular Design Considerations, Artik Patel Dec 2016

Design Optimization Of Pressure Vessel With Particular Design Considerations, Artik Patel

Mechanical and Aerospace Engineering Theses - Archive

The pressure vessels in industries are generally designed with a high safety factor because the rupture of a pressure vessel can be extremely dangerous. A vessel that is poorly designed or ineffectively designed to handle high pressure pose a very significant threat to life and property. Because of this, the design and verification of pressure vessels is governed by design codes specified by the ASME (American Society of Mechanical Engineers) Boiler and Pressure Vessel Code. The objective of this thesis work is to minimize the total weight of a real-world pressure vessel structure subjected to stress constraints specified by the …

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Smartwalker – Rolling Walker Instrumentation And Data Acquisition System Development To Monitor, Visualize And Store Rolling Walker Usage Data, Mauricio Jaguan Nieves Dec 2016

Smartwalker – Rolling Walker Instrumentation And Data Acquisition System Development To Monitor, Visualize And Store Rolling Walker Usage Data, Mauricio Jaguan Nieves

Mechanical and Aerospace Engineering Theses - Archive

The Smart Walker project was designed to fill a necessity of monitoring in real time the use of rolling walkers (RW) and study the causes that contribute to the high rate of fallings among its users. The main objectives of the project were to measure the major forces applied by RW users in real time and store it safely for further analysis. The first prototype of the Smart Walker includes the measurement of axial load, torque and gripping force applied on the handle as well as acceleration and rotation angles while it is being used. The axial load was measured …

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Automated System For The Characterization Of The Biomechanical Properties Of Human Soft Tissue, Michael R. Abraham Dec 2016

Automated System For The Characterization Of The Biomechanical Properties Of Human Soft Tissue, Michael R. Abraham

Mechanical and Aerospace Engineering Theses - Archive

Vaginal prolapse is a common condition that affects a large number (approximately 3.3 million in the US) of women, mainly above the age of 50 years. The condition is characterized by the weakening and breakdown of the pelvic support structures such as muscles and connective tissues, leading to the dislodging and prolapse of pelvic organs. Current examinations of the pelvic tissue are manually performed by the physician who assesses its rigidity. These exams are subjective and offer qualitative rather than quantitative results of the state of the pelvic tissue. In this research, a complete system was conceptualized and designed to …

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Automated Lattice Optimization Of Hinge Fitting With Displacement Constraint, Vignesh Dakshnamoorthy Dec 2016

Automated Lattice Optimization Of Hinge Fitting With Displacement Constraint, Vignesh Dakshnamoorthy

Mechanical and Aerospace Engineering Theses - Archive

Additive manufacturing enables fabrication of complex lattice cell structures that are not manufacturable using conventional methods. In order to exploit this lattice capability in structural designs, the effect on structural performance must be considered. This paper uses a goose neck door hinge component to illustrate the effects of lattice structure optimization when stiffness criteria drive part design. The effect of intermediate lattice cell density parameters on resulting lattice configurations from automated lattice structure optimization are studied and it is found that the compliance of the model depends upon the range of intermediate density elements present. The paper then compares the …

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Hole Size, Location Optimization In A Plate And Cylindrical Shell For Minimum Stress Points Interfacing Ansys And Matlab, Soundararaj Thangavel Dec 2016

Hole Size, Location Optimization In A Plate And Cylindrical Shell For Minimum Stress Points Interfacing Ansys And Matlab, Soundararaj Thangavel

Mechanical and Aerospace Engineering Theses - Archive

Discontinuities in Structures are inevitable. One such discontinuity in a plate and cylindrical shell is presence of a hole / holes. In Plates they are used for mounting bolts where as in Cylinder / Pressure Vessel, they provide provision for mounting Nozzles / Instruments. Location of these holes plays a primary role in minimizing the stress acting with out any external reinforcement. In this Thesis work, Location Parameters are optimized for the presence of one or more holes in a plate and cylindrical shell interfacing ANSYS and MATLAB with boundary constraints based on the geometry. Contour plots are generated for …

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A Methodology To Develop A Control System App For Data Center Cooling, Varun Rahul Dec 2016

A Methodology To Develop A Control System App For Data Center Cooling, Varun Rahul

Mechanical and Aerospace Engineering Theses - Archive

DCIM (Data Center Infrastructure Management), are tools that are available in the industry to serve the purpose of controlling different parameters in the data center. But their cost is significantly high. The idea of developing a tool that is easily accessible at highly competitive costs will be the USP for its development. While developing such a software tool, there will be a few points that will be thoroughly emphasized upon: The software tool will have the flexibility of being used on any Operating System. It will be portable i.e. it can be set up on any device that supports a …

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Interactive Analysis Of General Beam Configurations Using Finite Element Methods And Javascript, Christopher G. Hernandez Dec 2016

Interactive Analysis Of General Beam Configurations Using Finite Element Methods And Javascript, Christopher G. Hernandez

Mechanical and Aerospace Engineering Theses - Archive

Advancements in computer technology have contributed to the widespread practice of modelling and solving engineering problems through the use of specialized software. The wide use of engineering software comes with the disadvantage to the user of costs from the required purchase of software licenses. The creation of accurate, trusted, and freely available applications capable of conducting meaningful analysis of engineering problems is a way to mitigate to the costs associated with every-day engineering computations. Writing applications in the JavaScript programming language allows the applications to run within any computer browser, without the need to install specialized software, since all internet …

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Slicing Algorithm For Complex Contour Generation From Coarse Meshed Iso-Surface Data, Divya Hareshkumar Shukla Dec 2016

Slicing Algorithm For Complex Contour Generation From Coarse Meshed Iso-Surface Data, Divya Hareshkumar Shukla

Mechanical and Aerospace Engineering Theses - Archive

Finite element based topology optimization is used to develop complex geometric configurations for additive manufacturing. Complex coarse-meshed Iso-surface data is extracted from topology optimization results and smooth mathematical geometry must be fit to that data in order to accomplish further design development. To accomplish this geometry fitting, cross-section data must be extracted at specific locations. The stereo lithography (STL) file format is a triangular mesh format which can be developed using 3D CAD Software and is widely used for additive layer manufacturing processes. The main aim of this research work is to generate cross-section contours using a nearest tail-to-head distance …

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Experimental And Numerical Study Of Heat Transfer Phenomenon In A Micro Droplet Reactor, Chintan Jitendra Gandhi Dec 2016

Experimental And Numerical Study Of Heat Transfer Phenomenon In A Micro Droplet Reactor, Chintan Jitendra Gandhi

Mechanical and Aerospace Engineering Theses - Archive

Temperature is an important control parameter during chemical reaction process. Micro reactors have attracted much attention due to its capability of excellent heat and mass transfer, fast reaction, and inherent safety of small scale. Among various types of micro reactors, micro droplet as a batch reactor has its own advantages such as high multiplexing capability. However, strong heat dissipation characteristics of microscale systems (due to large surface to volume ratio) hampers the measurement and monitor of enthalpy changes during the reaction. This study mainly focuses on temperature monitoring at micro droplet reactor by using thin film resistance temperature detector (RTD). …

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An Open Source App-Hardware Setup To Control The System For Data Center Cooling, Anay Satish Darekar Dec 2016

An Open Source App-Hardware Setup To Control The System For Data Center Cooling, Anay Satish Darekar

Mechanical and Aerospace Engineering Theses - Archive

Control systems for data center cooling exists in the proprietary form and are often sold as part of the overall unit. They provide vital information related to the cooling systems and supply information on the temperature and humidity conditions inside the data center. Since most of these control systems software are proprietary they are expensive and hence not accessible to all. This project aims to develop a control system that operates on similar lines, but is economical and easily available. Developing a desktop or mobile based application not only gives the end user control over the cooling method (ex. DEC …

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Computational Study And Optimization Of Wet Cooling Media In Direct Evaporative Heat Exchanger, Tejas Vijay Bhongale Dec 2016

Computational Study And Optimization Of Wet Cooling Media In Direct Evaporative Heat Exchanger, Tejas Vijay Bhongale

Mechanical and Aerospace Engineering Theses - Archive

Evaporative cooling media pads are the primary component of importance in direct evaporative cooling units. To increase the overall efficiency of direct evaporative cooling systems, a wet cooling media pad is considered for further optimization in design and operation. An installation technique called ‘staging’ of cooling media pads is examined and evaluated for its incremental cooling, water usage, and operational cooling efficiency. For Staging, a cooling media is divided into multiple vertical sections, and separate water distribution headers control each part. Staging of cooling media can reduce water consumption in data centers and potentially lessen the amount of cooling media …

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Fabrication, Calibration And Characterization Of Micro-Scale Resistance Temperature Detectors, Kunjan Anilkumar Chaudhari Dec 2016

Fabrication, Calibration And Characterization Of Micro-Scale Resistance Temperature Detectors, Kunjan Anilkumar Chaudhari

Mechanical and Aerospace Engineering Theses - Archive

Through this research, fabrication, calibration and characterization of micro-scale Resistance Temperature Detector (RTD) were studied. The RTD is meant to sense the temperature at the micro scale level on the hot spot of integrated circuit devices. Material that we focused in this study was indium tin oxide (ITO). Indium tin oxide thin films are widely used as an electrode owing to its optically transparent and electrical conducting properties. However, ITO thin film behavior as an RTD has not been well studied yet, which we aimed in this study. The commercially available ITO thin film deposited on a glass substrate was …

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Fem Analysis Of Composite Stringers For An Airplane Fuselage, Akashsingh Birendrasingh Thakur Dec 2016

Fem Analysis Of Composite Stringers For An Airplane Fuselage, Akashsingh Birendrasingh Thakur

Mechanical and Aerospace Engineering Theses - Archive

With the advent of technology, materials have advanced many folds; One such technical revelation has been Fiber-reinforced Composite Materials. Composite materials have two major advantages, among many others: Improved strength and stiffness, especially compared to other materials on a unit weight basis. For example, Composite materials have stiffness comparable to the stiffness of steel but with a strength decimal order higher and more than three times lighter. These advantages have led to new aircraft and spacecraft designs that are radical departures from past efforts based on conventional materials. The stringers serve to take up(along with the skin) the compression and …

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Solder Ball Reliability Assessment Of Wafer Level Chip Scale Package (Wlcsp) Through Power Cycling, Bhavna Conjeevaram Dec 2016

Solder Ball Reliability Assessment Of Wafer Level Chip Scale Package (Wlcsp) Through Power Cycling, Bhavna Conjeevaram

Mechanical and Aerospace Engineering Theses - Archive

Failure analysis and its effects are major reliability concerns in electronic packaging. More accurate fatigue life prediction can be obtained after the consideration of all affecting loads on the electronic devices. When an electronic device is turned OFF and then turned ON multiple times, it creates a loading condition called Power Cycling. The die is the main heat source causing non-uniform temperature distribution. The solder ball reliability assessment of wafer level chip scale package (WLCSP) is done through computational methods such as Finite element analysis. WLCSPs use wafer level package technology which is an extension of the Wafer Fab process, …

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Computational Study Of Impact Of Thermal Shadowing In Non-Directed Flow For Air And Oil Cooled Servers. Form Factor Study And Customization Of Heat Sink For Data Center Application, Chinmay Hemantkumar Bhatt Dec 2016

Computational Study Of Impact Of Thermal Shadowing In Non-Directed Flow For Air And Oil Cooled Servers. Form Factor Study And Customization Of Heat Sink For Data Center Application, Chinmay Hemantkumar Bhatt

Mechanical and Aerospace Engineering Theses - Archive

In today’s networking world, the usage of Servers and Data centers has been increasing significantly with a corresponding increase in power. The data center energy efficiency largely depends on thermal management of servers. Currently, air cooling is the most widely used thermal management technology in data centers. However, air cooling is starting to reach its limits due to high powered microprocessors and packaging. To overcome these limitations of air cooling in data centers, liquid cooling methods are starting to gain more traction. Thermal shadowing is the effect in which temperature of a cooling medium increases by carrying heat from one …

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