Night vision enhancement systems (NVESs) have been developed to improve visibility at night through supplementing drivers' direct vision with additional information shown on a display, rather than replacing drivers' direct vision. Existing studies have shown that NVESs may increase recognition distance, but may also increase drivers' mental and visual distraction (eyes-off-road). Each scan of the display of the night vision enhancement system involves some visual and mental cost to the driver. Automatic pedestrian warnings (APWs) have been integrated... ]]> Linzhen Nie http://iris.lib.neu.edu/mech_eng_diss/47 http://iris.lib.neu.edu/mech_eng_diss/47 Wed, 08 May 2013 12:23:06 PDT This dissertation is focused on surface and mechanical characterization of freestanding biological and other nano-structures using atomic force microscopy including two parts: cell mechanics and nano-structure mechanics. The main purpose of this work is to investigate how the nano- / micro-scale mechanical properties affect macro-scale function.

In cancer cells, efficacy of drug delivery is oftentimes declined due to the thick dendritic network of oligosaccharide mucin chains on the cell surface. AFM is used to measure the force needed to pierce the mucin layer to reach the cell surface. A pool of ovarian, pancreatic, lung, colorectal and breast cancer cells are... ]]> Xin Wang http://iris.lib.neu.edu/mech_eng_diss/46 http://iris.lib.neu.edu/mech_eng_diss/46 Tue, 07 May 2013 13:36:57 PDT Carbon nanotubes (CNTs) have been widely used as potential components in reported nanoelectromechanical (NEM) devices due to their excellent mechanical and electrical properties. This thesis models the experiments by the continuum mechanics in two distinct scenarios.

In the first situation, measurements are made of CNT configurations after manipulations. Modeling is then used to determine the interfacial properties during the manipulation which led to the observed configuration. This technique is used to determine the shear stress between a SWNT bundle and other materials. During manipulation, a SWNT bundle slipped on two micro-cantilevers. According to the slack due to the slippage after... ]]> Yu-Chiao Wu http://iris.lib.neu.edu/mech_eng_diss/45 http://iris.lib.neu.edu/mech_eng_diss/45 Tue, 07 May 2013 11:43:03 PDT The cold spray process is an additive manufacturing technology primarily suited for ductile metals, and mainly utilized in coating surfaces, manufacturing of freeform parts and repair of damaged components. The process involves acceleration of solid micro-particles in supersonic gas flow and coating build-up by metal bonding upon high velocity impact (300-1200 m/s) onto a substrate. Coating deposition relies on the kinetic energy (impact velocity) of the particles. The main objective of this research was to investigate the mechanics of metal bonding upon high strain-rate deformation in order to improve the technological implementation of the process. The research covers a wider... ]]> Baran Yildirim http://iris.lib.neu.edu/mech_eng_diss/44 http://iris.lib.neu.edu/mech_eng_diss/44 Tue, 07 May 2013 09:31:03 PDT Assembly of nano building blocks offers a versatile route to the creation of complex 1, 2 and 3-dimensional homogenous or hybrid nanostructures with unique properties to be used in many applications including electronics, optics, energy, and biotechnology. Bottom-up directed assembly of nanoparticles has been recently considered as one of the best approaches to manufacture such functional and novel nanostructures. However, current directed assembly techniques have not been shown to make nanostructures homogeneous or hybrid materials with nanoscale precision at a high yield. This is mainly due to the lack of fundamental understanding of the forces driving the assembly of nanoparticles... ]]> Cihan Yilmaz http://iris.lib.neu.edu/mech_eng_diss/43 http://iris.lib.neu.edu/mech_eng_diss/43 Mon, 06 May 2013 10:34:02 PDT Mechanical load is believed to play a critical role in tissue formation, growth, maintenance, and disease in vertebrate animals. Although many studies have investigated the effect of mechanical stimuli on biological processes, the dynamics of these processes have not been closely explored. Live long-term observation of the collective behavior of Primary Human Corneal Fibroblasts (PHCFs) exposed to mechanical load could provide important insight into the mechanisms used by fibroblasts while they migrate, produce multilayered constructs and manage collagen deposition during the synthesis of organized ExtraCellular Matrix (ECM). Previous studies have shown that PHCFs produce locally organized and aligned ECM similar... ]]> Ramin Zareian http://iris.lib.neu.edu/mech_eng_diss/42 http://iris.lib.neu.edu/mech_eng_diss/42 Thu, 25 Apr 2013 13:11:16 PDT Single-walled carbon nanotubes (SWCNTs) are the ideal building blocks for the functional unit in next generation flexible and transparent electronics due to the combination of superior electronic transport and mechanical properties. Even though remarkable progresses have been made towards the assembly and transfer technologies of SWCNTs, highly controllable and affordable SWCNT-polymer hybrid system is still largely exclusive, due to the difficulties in achieving two most important requirements: i) miniaturized functional unit with deliberately controlled properties and ii) high-rate and large scale integration technologies to construct the functional unit into or onto flexible, transparent and insulating polymeric substrates at desired location... ]]> Bo Li http://iris.lib.neu.edu/mech_eng_diss/41 http://iris.lib.neu.edu/mech_eng_diss/41 Tue, 16 Apr 2013 08:35:05 PDT The research contained in this thesis focus on low dimensional semiconductor nanostructures: morphology of core-shell nanowires, vapor-liquid-solid growth of Si nanowires, and assembly of single-walled carbon nanotubes. The morphological instability of low dimensional epitaxial core-shell nanowires consisting dislocation-free and misfit-strained core/shell is investigated using a linear stability analysis. Molecular dynamics and Monte Carlo simulations are performed to study the surface segregation-induced freezing in Au-Si alloy system and the Au-catalyzed vapor-liquid-solid growth of Si nanowire based on the angular-dependent embedded atom method. The assembly of carbon nanotube networks and vertically aligned carbon nanotubes are investigated using coarse-grained molecular dynamics simulations.

The... ]]> Hailong Wang http://iris.lib.neu.edu/mech_eng_diss/40 http://iris.lib.neu.edu/mech_eng_diss/40 Tue, 09 Apr 2013 12:20:12 PDT The uniform-droplet-spray (UDS) process, a controlled capillary jet breakup process, provides an ultimate means for the direct manufacturing of mono-size balls of metals and alloys in diameters ranging about 40-1000 microns. Commercialization of mono-size balls has already been realized in electronics packaging industry and other potential applications are in R&D. However, the direct use of solidified mono-size balls in manufacturing critically hinges on the ability to control the size uniformity, surface quality and sphericity of the balls.

In the present research, the nucleation kinetics of mono-sized droplets of Fe-5Si-2.7B-0.4C-0.8Mo alloy (JH201) and 99.99% pure copper generated by the UDS process... ]]> Mehmet Bora Islier http://iris.lib.neu.edu/mech_eng_diss/39 http://iris.lib.neu.edu/mech_eng_diss/39 Tue, 12 Mar 2013 09:16:38 PDT A primary goal of modeling virtual environments for driving simulations is to reproduce the real world as completely as possible. Designers have to accurately represent the geometric information about real roadways and reproduce the real traffic as if autonomous agents were controlled by human beings. Another goal that is equally important is to build the virtual environment with efficiency. Both workloads and time consumed are expected to be minimized.

This thesis introduces improved methods to build large-scale driving simulations. The process of modeling the virtual environment is categorized into two levels: geometric and topological. Traditionally, most driving simulations model the... ]]> Zhishuai Yin http://iris.lib.neu.edu/mech_eng_diss/38 http://iris.lib.neu.edu/mech_eng_diss/38 Fri, 08 Mar 2013 12:07:13 PST Rehabilitation robotics is a rapidly developing field that shows great potential for aiding people with movement disabilities in their recovery, and consequently in improving their quality of life and independence. Rehabilitation robots not only serve as physical aids to therapists, but also present new avenues in rehabilitation that were formerly unavailable. Increased motivation can be achieved via interactive virtual environments. Their integrated sensing and data logging abilities can provide quantitative feedback on the patient progress and therapy outcomes, which in turn can guide us in defining more effective therapy methods.

The control strategies of rehabilitation robots differ significantly from that... ]]> Özer Ünlühisarcikli http://iris.lib.neu.edu/mech_eng_diss/37 http://iris.lib.neu.edu/mech_eng_diss/37 Fri, 08 Mar 2013 10:34:49 PST In recent years there has been an increasing interest in effective integration of nano scale functional oxides with semiconductors for third and fourth generation nano devices including high-K dielectrics based electronic devices and paradigm-shifting spintronics-based circuits. In this research we investigate the growth of MgO nano thin films on 6H-SiC substrate in a molecular beam epitaxy process. Here MgO serves as a template layer to minimize the mismatch with both substrate and a functional oxide films such as BTO and BaM. In this research we constructed neural network based process models using historical experimental data. Based on these process models... ]]> Ghulam Moeen Uddin http://iris.lib.neu.edu/mech_eng_diss/36 http://iris.lib.neu.edu/mech_eng_diss/36 Tue, 05 Mar 2013 09:35:09 PST Adhesion has significant impacts in life sciences, such as, cell adhesion, bacterial aggregation and drug delivery vesicles in micro-scale, and contact lens adhesion in macro-scale. In order to quantify adhesion, several classical models for solid adhesion were constructed and widely adopted by the scientific community over the past decades, such as the celebrated Johnson-Kendall-Roberts (JKR), Derjaguin-Muller-Toporov (DMT), and the Tabor-Muller-Maugisfs JKR-DMT transition models. However, nano-shells / particles, vesicles and biological cells are shells instead of solid spheres, rendering the classical models invalid. A new mechanics model is necessary for shell adhesion.

In this dissertation, adhesion models for two extreme shell... ]]> Jiayi Shi http://iris.lib.neu.edu/mech_eng_diss/35 http://iris.lib.neu.edu/mech_eng_diss/35 Tue, 05 Mar 2013 09:04:30 PST Calorimeter devices and temperature sensors are widely used tools in pharmaceutical, biochemical and clinical diagnostic application areas. The observed energy released during a reaction is a direct measure of the performance of the interaction between tested molecules. This information is important in selecting which compounds should be taken into later stages of drug development process. The main goal in the current calorimeter development research is to reduce the amount of valuable compound used and the experiment time. In the present research, the design and development of a calorimeter utilizing a photonic temperature sensor based on the Extraordinary Optical Transmission (EOT)... ]]> Mehmet Ali Sen http://iris.lib.neu.edu/mech_eng_diss/34 http://iris.lib.neu.edu/mech_eng_diss/34 Mon, 04 Mar 2013 08:05:45 PST The research presented investigates a new method and design of embedded sensors for medical applications using an injected piezoresistive elastomer inside a structure built using Additive Manufacturing (AM) methods as the exemplary fabrication. The sensing element is embedded into specifically designed geometry for hollow cavities and voids. Depending on the geometry and applied loads it can be used to sense different types of physical loads like force and torque. This expands the design capabilities of health care practitioners for such devices by not just building a custom-shaped part, but having the ability to monitor their interaction with the human, and... ]]> Richard G. Ranky http://iris.lib.neu.edu/mech_eng_diss/33 http://iris.lib.neu.edu/mech_eng_diss/33 Fri, 01 Mar 2013 09:00:39 PST The method of Rate-Controlled Constrained-Equilibrium (RCCE) has been further developed to study the combustion of CH₄/Air and C₂H₅OH/O₂/Diluent mixtures. The method is based on local maximization of entropy or minimization of a relevant free energy at any time during the non-equilibrium evolution of the system subject to a set of kinetic constraints. These constraints are imposed by slow rate-limiting reactions. Direct integration of the rate equations for the constraint potentials were used, once the values of which are known, the concentration of all species can be calculated.

It is well established that oxidation of C₁-C₂ molecules constitutes a major part... ]]> Ghassan Jawdat Nicolas http://iris.lib.neu.edu/mech_eng_diss/32 http://iris.lib.neu.edu/mech_eng_diss/32 Mon, 25 Feb 2013 08:45:57 PST Plastic anisotropy in rolled sheets has traditionally been analyzed by conducting tensile tests on strips cut at different angles from the rolling direction and measuring the contraction ratios during testing. This method is tedious, yet sufficient for sheet metals but the application to other material systems is limited. For example, if one were to seek the properties of a coating-substrate system, such an analysis would be impractical due to the combined effects of the coating and the substrate on which it lies. Indentation-based experiments are a great candidate for evaluation of such properties in various material systems for a few,... ]]> Salmon Masbooghi Kalkhoran http://iris.lib.neu.edu/mech_eng_diss/31 http://iris.lib.neu.edu/mech_eng_diss/31 Mon, 25 Feb 2013 08:10:30 PST Recent technological advancements have given birth to the growth in electronics and the availability of inexpensive products with high quality. Due to human nature, consumers constantly look for newer products although what they have may be still functional. Functional or not, used products are routinely discarded. This trend has led to extreme depletion of virgin resources to satisfy the ever increasing demands of the customers. In addition, the waste created by products reaching the end of their useful lives pose challenges for the environment. Environmental and economic concerns together with the stricter government regulations and public awareness on the disposal... ]]> Can B. Kalayci http://iris.lib.neu.edu/mech_eng_diss/30 http://iris.lib.neu.edu/mech_eng_diss/30 Thu, 07 Feb 2013 09:20:30 PST Optode based sensors present a novel approach for the development of new tools to make concentration measurements in biology. Currently measurements of cellular concentrations are performed with fluorescence molecular probes that optically report concentrations from within cells. However, these probes are capable of measuring the concentration of a few ions, which limits the understanding of complete cellular function. Electrophysiology measurements are also used to determine cellular ion channel function, but do not provide specificity of ion activity, requiring the uses chemicals that alter overall cellular function. In other biological measurements, concentration measurements of the blood require blood removal from the... ]]> John Dubach http://iris.lib.neu.edu/mech_eng_diss/29 http://iris.lib.neu.edu/mech_eng_diss/29 Fri, 01 Feb 2013 09:44:10 PST Bone remodeling and bone healing are both complex biological processes that involve well-coordinated cellular activities. Mechanical loading is believed to influence the cellular responses during the development, maintenance, adaptation, and repair of bone. The works contained within this dissertation are aimed to investigate that the role of mechanics plays in the (1) mandibular bone development, (2) bone remodeling around dental implant, and (3) bone healing around dental implant. Regulatory algorithms of bone remodeling and bone healing are implemented in the finite element models.

In the first part of this work, the mandibular bone is shown to be determined by bone... ]]> Hsuan-Yu Chou