Mechanical Engineering Commons^™

Development Of Economic Water Usage Sensor And Cyber-Physical Systems Co-Simulation Platform For Home Energy Saving, Joe Singer

Mechanical Engineering Master's Theses

In this thesis, two Cyber-Physical Systems (CPS) approaches were considered to reduce residential building energy consumption. First, a flow sensor was developed for residential gas and electric storage water heaters. The sensor utilizes unique temperature changes of tank inlet and outlet pipes upon water draw to provide occupant hot water usage. Post processing of measured pipe temperature data was able to detect water draw events. Conservation of energy was applied to heater pipes to determine relative internal water flow rate based on transient temperature measurements. Correlations between calculated flow and actual flow were significant at a 95% confidence level. Using …

Material Characterization Of Intermetallic Compound Formation With Respect To Thermosonic Bonding Duration, Mahin Khan

Mechanical Engineering Master's Theses

Intermetallic Metallic Compounds (IMCs) formation is a common cause for wire bond failures. This research studied the effect of US vibration duration on IMC formation and growth in Copper-Aluminum (Cu-Al) wire bonded samples. Wire bonded samples, using 2.5 mil (63.5 μm) thick Palladium coated Copper wire, is ultrasonically bonded on a 2 cm thick Aluminum (1”x1”) coupon. Segmented bonding technique using 200 gf force and 220 gf force are applied during segment 1 and segment 2 of the bonding respectively. Ultrasonic (US) vibration frequency of 115-117 khz and a bonding temperature of 175°C is used. A pair of 5 samples …

Evaluation Of Heat Available From Calcium Chloride Desiccant Hydration Reaction For Domestic Heating In San Francisco, Ca, Michael Giglio

Mechanical Engineering Master's Theses

Thermochemical energy storage has the potential to support the use of solar thermal energy collection in ways that traditional thermal energy storage, like sensible and latent heat storage, have fallen short. Thermochemical energy storage has been shown to have higher storage capacities than sensible and latent storage for dehumidifying applications and does not require insulation like sensible and latent heating do. Sensible heating is focused on maintaining an increased temperature of a storage medium while latent heat storage is focused on maintaining a phase of the storage material. Both sensible and latent heat storage have been shown to have lower …

Computerized Heat Transfer Modeling For Solar Powered Water Purification System, Houtan Neynavaee

Mechanical Engineering Master's Theses

Since drinkable water resources are limited, as the human population increases it is predicted that providing pure water is a future human challenge. However, a huge resource of the water exists on the earth surface in seas and oceans, which are not proper for drinking and cultivate. Exploiting of a solar powered water purification system is an economy and environment-friendly solution to this human problem.

In this thesis, we present computerized heat transfer model for solar powered water purification system. This Model can be used for calculating the heat transfer, system temperature, and other variable parameters such as boiler pressure, …

Influence Of Slippery Pacemaker Leads On Lead-Induced Venous Occlusion, Sagar Bhatia

Mechanical Engineering Master's Theses

The use of medical devices such as pacemakers and implantable cardiac defibrillators have become commonplace to treat arrhythmias. Pacing leads with electrodes are used to send electrical pulses to the heart to treat either abnormally slow heart rates, or abnormal rhythms. Lead induced vessel occlusion, which is commonly seen after placement of pacemaker or implantable cardiac defibrillators leads, may result in lead malfunction and/or superior vena cava syndrome, and makes lead extraction difficult. The association between the anatomic locations at risk for thrombosis and regions of venous stasis have been reported previously. The computational studies reveal obvious flow stasis in …

Hybrid Fuzzy Logic And Extremum Seeking Attitude Control Of Solar Sail Spacecraft, Nikolai Kalnin

Mechanical Engineering Master's Theses

This thesis explores four controllers applied to the attitude control of a solar sail craft with control masses with the goal of showing benefits over more standard control schemes. The controllers examined in this paper are: 1) a PID controller that incorporates a discrete extremum seeking algorithm, 2) a type-1 fuzzy logic controller that incorporates a discrete extremum seeking algorithm, 3) a type-1 fuzzy logic controller, and 4) a type-2 fuzzy logic controller. The first two controllers are examined for their ability to quickly converge to a set of optimal gains over time. The latter two controllers are evaluated for …

Object Manipulation Using A Multirobot Cluster With Force Sensing, Matthew H. Chin

Mechanical Engineering Master's Theses

This research explored object manipulation using multiple robots by developing a control system utilizing force sensing. Multirobot solutions provide advantages of redundancy, greater coverage, fault-tolerance, distributed sensing and actuation, and reconfigurability. In object manipulation, a variety of solutions have been explored with different robot types and numbers, control strategies, sensors, etc. This research involved the integration of force sensing with a centralized position control method of two robots (cluster control) and building it into an object level controller. This controller commands the robots to push the object based on the measured interaction forces between them while maintaining proper formation with …

A Molecular Dynamics Study Of Self-Diffusion Along A Screw Dislocaton Core In Face-Centered Cubic Crystals, Siavash Soltanibajestani

Mechanical Engineering Master's Theses

The topic of this research is self-diffusion along a 1⁄2 〈110〉 screw dislocation core in face-centered cubic metals. Using molecular dynamics, self-diffusion along a screw dislocation core in four FCC metals, aluminum, copper, nickel and silver is investigated. In all metals under study except in Ag, the results show high diffusivity along the core even in the absence of any preexisting point defects (intrinsic diffusion). Enhanced self-diffusion due to screw dislocations is more remarkable in Al and Ni than in Cu. This behavior has been related to the stacking fault energy and dissociation width of partial dislocations.

The simulations show …