Engineering Commons^™

Comparison Of Martin’S Empirical Correlation With Measurements On A Compact Plate Heat Exchanger, Abdulmohsen A. Alothman

Masters Theses

The need for more effective heat exchangers is becoming more necessary these days. At the same time, the size of the heat exchanger also plays a big role. Therefore, in many applications the compact plate heat exchanger is used where high effectiveness and small size are required. As a result, it is a necessary to study and understand the performance of compact plate heat exchangers. More specifically, the performance of heat transfer, represented by the Colburn factor j, and friction factor f, must be deeply studied and understood.

A mathematical model has been built to express f and j factors …

Evaluation Of Silver/Graphite Ink Blends For Use In Printed Electronics, Sagar Satish Joshi

Masters Theses

Many organizations around the globe are actively involved in the research and development of printed displays, circuits, printed batteries, RFID tags and other printed electronics applications. The requirements for using printing techniques in the manufacturing of circuits are much more demanding than for conventional printing.There are many challenges that have to be overcome for successful printing and functioning of the printed circuits. These challenges are not only for the printing process and the substrates, but also for the functional inks used for printed electronics manufacturing.

This work focuses on gravure printing of conductive inks, more specifically silver, graphite and silver-graphite …

Parametric Study Of Gear Rattle And The Effect Of Flexible Enclosures On Gearbox Vibratory Responses, Joshuah Thomas Racine

Masters Theses

Gearbox noise emitted from vehicles has become of particular importance to manufacturers due to the significant reduction of engine and masking noises in most modem designs. The reduction of gearbox rattle was the subject of this research using Romax Designer. Both drive and neutral loading conditions were considered for a parametric study of the influence of altering input torque fluctuation, backlash between gears, component rigidities and driveline inertia. Next, an external enclosure was added, where its effect was studied by altering the wall thickness, material properties and fixed boundary positions. Finally, results obtained from Romax Designer for a physical gearbox …

On-Board Monitoring Of Engine Oil, Ryan James Clark

Masters Theses

Engine oil condition was quantified in a diesel engine through direct, real-time measurements of lubricant properties using an on-board oil-condition sensor. The sensor measures the lubricant temperature, density, dynamic viscosity and dielectric constant. Comparative bench-top experiments using ASTM methods or equivalent techniques validated the accuracy and precision of the lubricant property measurements from the oil-condition sensor for a specific temperature range. Bench-top experiments were also used to establish correlations between fuel contamination levels and changes in lubricant properties.

Through engine experiments, the change in the lubricant properties with respect to operating time was quantified. A correlation was found between the …

Ductile Mode Material Removal Of Ceramics And Semiconductors, Deepak Ravindra

Dissertations

Ceramics and semiconductors are hard, strong, inert and lightweight. They also have good optical properties, wide energy bandgap and high maximum current density. This combination of properties makes them ideal candidates for tribological, semiconductor, MEMS and optoelectronic applications respectively. Manufacturing these materials without causing surface and subsurface damage is extremely challenging due to their high hardness, brittle characteristics and poor machinability. However, ductile regime machining of these materials is possible due to the high-pressure phase transformation occurring in the material caused by the high compressive stresses induced by the single point diamond tool tip. In this study, to further augment …

Beading And Dimpling Techniques To Improve The Vibration And Acoustic Characteristics Of Plate Structures, Nabeel Taiseer Alshabtat

Dissertations

A method of improving the vibroacoustic characteristics of beams and plates is presented. This method is based on creating dimples or beads on the surface of the structures. The proposed method couples the finite element method with an optimization technique based on the genetic algorithm (GA). The improvement of the vibroacoustic characteristics of beams and plates is achieved by two separate strategies. The first strategy is optimizing the natural frequencies of beams and plates. The second strategy is minimizing the sound radiation from such vibrating structures. Optimizing the natural frequencies of some types of beams and simply supported plates by …

Cross-Layer Design For Mobile Ad-Hoc Unmanned Aerial Vehicle Communication Networks, Abdel Ilah Nour Alshbatat

Dissertations

Mobile Ad-Hoc network (MANET) is a popular type of wireless network that is formed by a collection of mobile nodes. Each node in such a network has the capability to communicate with its neighbors and non-neighbors through a wireless medium without using any existing network infrastructure. Due to the lack of infrastructure, all nodes in Ad-Hoc network are designed to act as an end system and a router for other nodes.

Traditionally, the dominant design methodology for network protocols was based on the open systems interconnection (OSI) reference model. This methodology divided the stack into seven layers in which each …

A Study To Determine The Influence Of Workload On Nursing Personnel, Supreeta G. Amin

Dissertations

The alarming number of adverse medical events and associated costs have placed immense importance toward the safety and health of both patients and medical personnel. A shrinking nurse workforce, an aging patient and nursing population coupled with a mismatch between hospital demands and the available nursing staff have created a situation detrimental to both patient and nursing personnel. Long working hours, working more than one job, low staffing ratios, high patient acuity, minimal social support, low experience level, complicated equipment, complex procedures and varying workload are some factors that may have a negative impact on the quality of care provided …

Leach-Sm: A Protocol For Extending Wireless Sensor Network Lifetime By Management Of Spare Nodes, Bilal Abu Bakr

Dissertations

Operational lifetime of a wireless sensor network (WSN) depends on its energy resources. Significant improvement of WSN lifetime can be achieved by adding spare sensor nodes to WSN. Spares are ready to be switched on when any primary (a node that is not a spare) exhausts its energy. A spare replacing a primary becomes a primary itself.

The LEACH-SM protocol (Low-Energy Adaptive Clustering Hierarchy with Spare Management) proposed by us is a modification of the prominent LEACH protocol. LEACH extends WSN lifetime via rotation of cluster heads but allows for inefficiencies due to redundant sensing target coverage. There are two …

Virtual Design Verification And Process Improvement Of Composite Sheet Material Products Using Intelligent Finite Element Analysis (Ifea), Sathyanarayanan Narasimhan

Dissertations

Engineering design decisions influence more than 70% of product costs. Various computational analysis tools such as Finite Element Analysis (FEA) are typically utilized, to achieve an effective design cycle. Literature review in design process indicates a striking reality that about 75% of design errors can be eliminated through analysis and about 20% of analyses are misrepresented, leading to inadequate or faulty design. Also, analyses in general, generate more information about the problem than is often looked into, leading to a vast potential to study the knowledge creation.

This research bridges these gaps in design process through efficient use of computer-based …

New Media Icc Profiles Construction And Concerns, Reem El Asaleh

Dissertations

With the advent of the modern digital technology, users can now capture an image and reproduce it between different media, such as display it on LCD monitor or tablet computer, print it on desktop printer or send it to a printing press. The challenge has been then to maintain the accuracy of image colors during this reproduction, which has led to the development of Color Management Systems. Using these systems, the color reproduction across-media will be accomplished using device ICC profiles that describe each device’s color characterization data in a standardized format based on International Color Consortium (ICC) specifications.

ICC …

Direct Forcing And Heating Immersed Boundary- Lattice Boltzmann Method For Arterial Wall Thermography, Oluyinka Olugbenga Bamiro

Dissertations

Vulnerable atherosclerotic plaques have high probability of rupture and are characterized by non-homogenous temperature along the arterial wall. The nonhomogeneous temperature is attributed to the accumulation of heat releasing inflammatory cells in the arterial wall. Rupture of the vulnerable plaque can lead to acute coronary syndrome and sudden cardiac death. Arterial wall thermography (AWT) can be applied to detect the presence of temperature hot spots along the arterial wall by using temperature measurement devices and provide an early detection of a vulnerable atherosclerotic plaque. AWT, however, is invasive in nature.

Computational fluid and heat transport models provide a more efficient …

Benefits Of Cpfr And Vmi Collaboration Strategies In A Variable Demand Environment, Dattaraj Kamalapurkar

Dissertations

In recent years, practitioners and academic researchers have emphasized that organizations need to collaborate with suppliers and customers to improve their competitive advantage. The availability of cost efficient information technologies like EDI, XML, etc. have made it possible to develop and implement many forms of collaboration strategies. Among them, Vendor Managed Inventory (VMI) and Collaborative Planning, Forecasting and Replenishment (CPFR) are most popular, which are considered for this study. While many studies have identified the benefits of demand information sharing in supply chains; however the benefits gained by implementing collaboration strategies like VMI and CPFR in a variable demand environment …