Theses and Dissertations

Intramedullary (IM) nailing is a common fixation procedure for fractures of the distal femur (thighbone). These injuries are commonly associated with older individuals, and aging population demographics present the need to investigate IM nailing procedures for distal femur fracture fixation in osteoporotic bone.

AbstractVarious strain-compensated InGaN-AlGaInN quantum well (QW) structures are investigated by self-consistent 6-band k∙p method, which considers valence band mixing, the strain effect, spontaneous and piezoelectric polarizations and the carrier screening effect, for their spontaneous emission and gain properties. The InGaN QW with In-content of 28% is sandwiched by AlGaInN barriers, which are Al0.2Ga0.8N, Al0.56Ga0.32In0.12N, Al0.72Ga0.13In0.15N, Al0.78Ga0.1In0.12N, and Al0.82Ga0.1In0.08N, with corresponding band gaps of 3.821eV, 4.156eV, 4.465eV, 4.765eV, and 5.065eV, respectively.

Nowadays CAD/CAM/CNC is widely used in all fields of manufacturing andproduction. With the help of them, ideas and designs can be quickly and accuratelybrought to reality. This thesis deals with manufacturing of rather complex high-strengthaluminum parts. The parts will be used for a new kind of alpine ski which incorporatessuspension with springs and dampeners. The requirements of the parts are quite typicalfor high-performance equipment - they need to be lightweight, strong, stiff, and aresubjected to various packaging constraints.

With the advent of nanotechnology, many fields of Engineering and Science took a leap to the next level of advancements. The broad scope of nanotechnology initiated many studies of heat transfer and thermal engineering. Nano-fluids are one such technology and can be thought of as engineered colloidal fluids with nano-sized colloidal particles. There are different types of nano-fluids based on the colloidal particle and base fluids. Nano-fluids can primarily be categorized into metallic, ceramics, oxide, magnetic and carbon based.

A novel additive manufacturing technique is proposed for printing polymers withcontrolled and spatially varying rheological properties. The technique, the Parallel Plates,involves altering the flow area of the polymer melt inside the printing head and applying acontrolled shear on the polymer melt.

A systemic analysis of the influence of experimental conditions on growth of anodic nanostructures on copper was performed. An aqueous electrolyte composed of 0.01 M sodium bicarbonate was used in order to form oxide nanostructures on the surface of coppe

This work determines optimal planar geometric light source and optical imager configurations and electromagnetic wavelengths for maximizing the reflected signal intensity when using machine vision technology to image roadway markings with embedded spherical glass beads. It is found through a first set of experiments that roadway marking samples exhibiting little or no bead rolling effects are uniformly reflective with respect to the azimuthal angle of observation when measured for retroreflectivity within industry standard 30-meter geometry.

In response to the high cost and limited instrumentation available on commercial tribometers a student designed tribometer was conceived, built, and tested. This tribometer combines multiple tribology testing configurations into a single compact and reconfiguration tribometer, dubbed the multifunctional tribometer. This tribometer is also capable of operating in expanded experimental spaces not covered within the limited scope of industry standardized tribological tests.

In DCDS (Distributed Control and Dynamical Systems) laboratory, we are using quadcopter flying inside the building with motion capture system. In the quadcopter base, we are designing a new flight controller which has a high-speed processor and fast Wi-Fi communication. And the price is affordable in case of crashes during the research.The IMU used on the quadcopter is MPU6050 and HMC5883L magnetometer, they provide accurate Euler angle, angular velocity and heading at 200Hz.

The topic of this thesis is coal pre-treatment for mercury and sulfur removal before combustion. Mercury is a neuro toxic impacted in health issue, and is targeted by strict environment regulations. Thermal desorption was used in this investigation, since mercury exists in coal as different mercury species, which can be released at different pre-combustion temperatures. To achieve the thermal desorption process, two different kind of spouted beds, provided by the Advanced Cooling Technologies (ACT), Inc. were tested at the Lehigh University Energy Research Center.

The understanding of balance and sway remain a continuous field of study for avariety of purposes such as the understanding of what sorts of balance cause falls and injuryto happen, as well as what can be done to prevent this injury. Balance and sway amon

With increase in the indoor usage of communication, there has been increase in the need for optimal design of mobile coverage for buildings with a lot of users. Cellular service companies had been pushing the limits with their macro-cell approach however, with the advent of 4G LTE and their higher frequency use, the penetration inside the buildings adds to their troubles. A Distributed Antenna System(DAS) extends the mobile coverage from the base station to distributed antennas through a network topology of coaxial cables and power splitters.

This work presents a new numerical method for processing atomic force microscopy (AFM) data to determine the elasticity of cultured adherent biological cells. Raw AFM force-indentation data is commonly interpreted using the Hertz and Sneddon contact mechanics models to fit a Young’s modulus or apparent cell elasticity. This apparent cell elasticity is highly dependent on the method used to identify the first point of contact between the AFM probe and the cell surface.

This thesis discusses the problem of characterizing, identifying and computing a class of critical configurations of a multi-segment robot arm in planer workspace with point obstacles. The motivation of this research is to efficiently solve the path plann

Acceleration is a basic concept in physics and engineering which is widely applied in fluid mechanics and vibration analysis. Recently, research has evolved to create a miniature device capable of measuring three components of acceleration. Electrical engineers have created a device called MinIMU-9 v2 that measures three components of acceleration. The system obtains acceleration components paralleling global (earth) coordinates. MinIMU-9 is designed to connect with an Arduino board (hardware) to maximize its functionality.

Over the past decade, select multi-principal element alloys (MPEAs) have exhibited excellent structural properties, especially at high temperatures, outperforming conventional alloys in some cases. Phase stabilization by entropy maximization has been attributed, albeit inconclusively, as one of the primary factors underlying such unique material properties. A conventional approach to discovering new MPEAs requires scavenging an enormous search space consisting of over half a trillion new material compositions.

A suspension boat concept was developed and patented by Grenestedt [1] with the purpose to reduce high vertical accelerations when a boat operates at high speed in waves. A two-seat manned suspension boat is presently being built in the Lehigh University

The human mind is very imprecise and uncertain most of the time. We are allowed to think as we wish, as things really are. This, however, is not how computers are designed to allow us to solve realistic problems. Now the question arises: how do we represent uncertainty and impreciseness using very accurate devices? In order to add flexibility into mechanical design, fuzzy logic can be used to represent the imprecise data, such as how humans think.

The III-nitride material system has revolutionized the 21st century solid statelighting industry with the development of power-saving blue and white light-emitting diodes. Current research efforts into this material system include achieving highefficiency at longer wavelengths (green into red and beyond), the development of low-threshold current density and high gain solid state lasers, extending the capabilities of these materials into high voltage and current density power electronic devices, and reducing the cost of devices to compete with alternatives on the market.

Tissue engineering has a significant impact on biological and medical area. It helps to eventually realize the repair, replace or improve tissue function or even the complete organ. Inkjet cell printing, as a simple and novel way in bio-fabrication, is a promising tool to fabricate cell pattern and scaffolds that directly serve the purpose of tissue engineering.This thesis introduces a thermal inkjet cell printing device. The mechanical design, software and pertinent test data are described.

The Lehigh Ocean Research Craft Autonomous, or LORCA, was designed and built at Lehigh University's Composites Laboratory as a versatile unmanned boat, or Unmanned Surface Vehicle (USV). Ten 1.2m long boats have been built in various configurations, with the last seven built identically. The boat is fully self-righting with an enclosed electric motor, allowing it to be deployed in ocean conditions and rolled over without losing power or damaging equipment. Composite materials were used wherever possible in construction resulting in a craft that is strong, fast, and lightweight.