Página 16 dos resultados de 10406 itens digitais encontrados em 0.017 segundos

‣ Fabrication of microfluidic devices for artificial respiration

Park, Hyesung, Ph. D. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 108 p.
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We are developing elastomeric polydimethylsiloxane (PDMS) microfluidic devices incorporated with photoactive thin films to create an implantable artificial respiration platform. Whereas state-of-the-art respiration support machines deliver oxygen gas directly to the blood via external macroscale devices, our technique utilizes a biomimetic photocatalytic process to generate energy from light and thus produce dissolved oxygen from water which is already present in the blood. Blood oxygenation will be achieved by the interaction between the photoactivated metal oxide film and blood in the setting of a molded microfluidic conduit, providing a stable and implantable oxygenation platform. As a basic, scalable building block, we developed a noble "network" design which was structurally similar to the native pulmonary capillary network. The interconnected channel geometry was designed in such a way to minimize shear stress and reduce hemolysis and thrombosis inside the microchannel. It allowed alternative flow pathways in the event of single channel occlusion while minimizing the establishment of detrimental pressure gradients. The hemocompatibility analysis demonstrated that the network construct showed acceptable levels of hemolysis rate (< 8%) and thrombus formation.; (cont.) Critical to the success of this project is the understanding of the manufacture parameters for microfluidic devices molded from elastomeric materials like PDMS. In the initial development of our work...

‣ Designing a simple, robust, precision robotic platform for medium quantity production

Lieberman, Janet Samantha
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 21 p.
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A niche which has yet to be saturated in the growing market of educational and research robotic platforms is the mechanically-simple, electronically-powerful research robot. Useful in fields such as algorithm and artificial intelligence research, such a robot would support a variety of sensor configurations and run both precisely and autonomously. Such a robot requires a robust, simple, preassembled mechanical platform; an electronics system which easily accepts a variety of sensors; and user friendly computer interface. This paper follows the design of a drive system and chassis for such a robot. Although the prototype developed did not meet the specifications of $250-$500 selling price for five hundred units, data was gathered from the prototype which will allow for a more cost effective redesign.; by Janet Samantha Lieberman.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.; Includes bibliographical references (p. 21).

‣ Design and fabrication of meso-scale flexural testing apparatus for evaluating aligned CNT composite flexures

Panas, Robert M. (Robert Matthew)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 62 p.
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The objective of this research is to explore the possibility of using aligned Carbon Nanotube (CNT) based composites in flexures by measuring the kinematics of a composite flexure. The first phase of the research, described in this thesis, is to design, fabricate and assemble a testing apparatus optimized for evaluating aligned CNT based composites. Using existing literature on composites and present limitations on their growth, functional requirements are set down for the testing apparatus. Several designs are qualitatively evaluated, leading to a near optimal design form. This chosen design is modeled as a spring-mass system, and the exact geometry needed to satisfy the functional requirements is determined. The design of the full apparatus is expanded to contain the necessary probes and actuators. The testing apparatus is fabricated using CNC machining, and assembled in a controlled environment to reduce thermal and mechanical error during operation. The system is calibrated and its resolution is found to be 0.021 N over a range of 28.5 N applied force and 1.5 pm over a range of 816 pm applied displacement. Several non-linearities are noted and corrected mathematically.; by Robert M. Panas.; Thesis (S.B.)--Massachusetts Institute of Technology...

‣ Cryogenic, compressed, and liquid hydrogen fuel storage in vehicles

Reyes, Allan B
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 26 p.
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Hydrogen is the viable energy carrier of future energy and transportation systems due to its clean emissions, light weight, and abundance. Its extremely low volumetric density, however, presents significant challenges to storage onboard vehicles. The study involves a survey of the current state of direct hydrogen storage technologies-cryogenic, compressed, and liquid storage-and an analysis of the problems associated with its storage. The significant storage problems that are reviewed and analyzed are issues with cool-down, boil-off, dormancy, materials, and space limitations. The goal of this study is to ultimately provide design insights on storage tanks, whether they be built for thermal performance (insulated), mechanical performance (pressure vessels), or both. The critical parameter that is analyzed is the inner shell wall thickness, or the layer that holds and encompasses the fuel. Graphs were provided to illustrate the reliance of the aforementioned problems on inner shell wall thickness. The results show that-given current materials-a nominal thickness of 10 cm is appropriate for liquid storage and a thickness of 4 cm is appropriate for flexibly fuelled storage and cryogenic compressed storage mechanisms.; (cont.) Additionally...

‣ Wear modeling with sensitivity to lubricant chemistry

Thomas, Benjamin C. (Benjamin Carl)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 91 p.
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The life of an automotive engine is often limited by the ability of its components to resist wear. Zinc dialkyl-dithiophosphate (ZDDP) is an engine oil additive that reduces wear in an engine by forming solid antiwear films at points of moving contact. The effects of this additive are fairly well understood, but there is little theory behind the kinetics of antiwear film formation and removal. This lack of dynamic modeling makes it difficult to predict the effects of wear at the design stage for an engine component or a lubricant formulation. The purpose of this research is to develop a theoretical and numerical framework for modeling the formation and evolution of ZDDP antiwear films based on the relevant chemical pathways and physical mechanisms at work. The ability to predict the development and function of thin solid films on rough surfaces and their effect on surface wear would be a useful tool in many tribological applications, both automotive and otherwise. Completely deterministic modeling of such films may not be possible due to the complex interactions between the numerous mechanical, thermal, and chemical variables over disparate magnitudes of time and length scales. However, it is believed that useful predictions can be made by constructing a mechanistic model in which all of the most important effects are included...

‣ Powered ankle-foot prosthesis for the improvement of amputee walking economy

Au, Samuel Kwok-Wai
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 108 p.
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The human ankle provides a significant amount of net positive work during the stance period of walking, especially at moderate to fast walking speeds. On the contrary, conventional ankle-foot prostheses are completely passive during stance, and consequently, cannot provide net positive work. Clinical studies indicate that transtibial amputees using conventional prostheses exhibit higher gait metabolic rates as compared to intact individuals. Researchers believe the main cause for the observed increase in metabolism is due to the inability of conventional prostheses to provide net positive work at terminal stance in walking. This objective of this thesis is to evaluate the hypothesis that a powered ankle-foot prosthesis, capable of providing active mechanical power at terminal stance, can improve amputee metabolic walking economy compared to a conventional passive-elastic prosthesis. To test the hypothesis, a powered prosthesis is designed and built that comprises a unidirectional spring, configured in parallel with a force-controllable actuator with series elasticity. The prosthesis is controlled to mimic human ankle walking behavior, in particular, the power generation characteristics observed in normal human walking. The rate of oxygen consumption is measured as a determinant of metabolic rate on three unilateral transtibial amputees walking at self-selected speeds. The initial clinical evaluation shows that the powered prosthesis improves amputee metabolic economy from 7% to 20% compared to the conventional passive-elastic prostheses (Flex-Foot Ceterus and Freedom Innovations Sierra)...

‣ Development of an inertial generator for embedded applications in rotating environments

Conrad, Stephen D. (Stephen David)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 179 p.
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Inertial generators are devices that generate electrical energy from their inertial motion, and have only one mechanical connection with their surroundings. This makes them suitable power sources for embedded systems operating in environments that experience some inertial excitation. Typical inertial generators are designed to generate electricity from linear vibrations, and are often termed vibrational energy harvesters. Traditional sprung mass vibrational energy harvesters must be tuned to achieve resonance at a specific frequency, and perform poorly when the excitation does not fall within a narrow band around this natural frequency. In this thesis, a novel inertial generator is proposed that is specifically designed to take advantage of the unique inertial loads experienced by a system embedded within a large scale rotating part with a horizontal axis of rotation, such as the propeller of a large ship. The design process begins with the identification of the inertial path and then proceeds with the development of a device that takes advantage of the unique inertial loads experienced along that path. The device is designed to achieve resonance at any steady state rotation rate, without any active forms of actuation. This is achieved by utilizing centrifugal forces to produce a natural frequency that tracks the excitation frequency. Experimental results from full-scale spin testing verify that the device has a monotonically increasing power output with increasing frequency. This result contrasts sharply with the frequency response of a traditional sprung mass vibrational energy harvester...

‣ Mechanotransduction by talin : a molecular dynamics study of force-induced recruitment of vinculin to a focal adhesion complex; Molecular dynamics study of force-induced recruitment of vinculin to a focal adhesion complex

Lee, Seung Eun, Ph. D. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 149 p.
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It is now well established that cells can sense mechanical force, but the mechanisms by which force is transduced into a biochemical signal remain poorly understood. One example is the recruitment of vinculin to reinforce initial contacts between a cell and the extracellular matrix due to tensile force. Talin, an essential structural protein in the adhesion, contains the N-terminal five-helix bundle in the rod domain with a known cryptic vinculin binding site 1 (VBS1). The perturbation of this stable structure through elevated temperature or destabilizing mutation activates vinculin binding. Here, molecular dynamics (MD) is employed to demonstrate a force-induced conformational change that exposes the cryptic vinculin-binding-residues of VBS1 to solvent under applied forces along a realistic pulling direction. VBS 1 undergoes a rigid body rotation by an applied torque transmitted through hydrogen-bonds and salt bridges. Activation was observed with mean force of 13.2±8.0pN during constant velocity simulation and with steady force greater than 18.0pN. The crystal structure of vinculin head subdomain (Vhl) bound to the talin VBS1 implies that vinculin undergoes a large conformational change upon binding to talin, but the molecular basis for this...

‣ On a class of strain gradient plasticity theories : formulation and numerical implementation

Lele, Suvrat Pratapsinh
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 251 p.
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This study develops strain-gradient theories for isotropic and crystal plasticity. The following four theories were developed and numerically implemented: * A one-dimensional theory to understand the basic nature of strain gradient theories; * A small deformation crystal plasticity theory; * A small deformation theory for isotropic viscoplastic materials; and, * A large deformation theory for isotropic viscoplastic materials. The theories are based on: (i) microstresses consistent with microforce balances; (ii) a mechanical version of the two laws of thermodynamics for isothermal conditions, that includes via the microstresses the work performed during viscoplastic flow; and (iii) a thermodynamically consistent constitutive theory. The microscopic force balance, when augmented by constitutive relations for the microscopic stresses, results in a nonlocal flow rule in the form of a second-order partial differential equation for the plastic strain. The flow rule, being nonlocal, requires microscopic boundary conditions. The theories are numerically implemented by writing a user-element for a commercial finite element program. Using this numerical capability, the major characteristics of the theory are revealed by studying the standard problem of simple shear of a constrained plate. Additional boundary-value problems representing idealized two-dimensional models of grain-size-strengthening and dispersion-strengthening of metallic materials are also studied using the small deformation version of the isotropic theory. For problems that do not involve boundary conditions on plastic strain...

‣ Robust adaptive control of switched systems

El-Rifai, Khalid, 1979-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 158 leaves
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In this thesis, robust adaptive controllers are developed for classes of switched nonlinear systems. Switched systems are those governed by differential equations, which undergo vector field switching due to sudden changes in model characteristics. Such systems arise in many applications such as mechanical systems with contacts, electrical systems with switches, and thermal-fluidic systems with valves and phase changes. The presented controllers guarantee system stability, under typical adaptive control assumptions, for systems with piecewise differentiable bounded parameters and piecewise continuous disturbances without requiring a priori knowledge on such parameters or disturbances. The effect of plant variation and switching is reduced to piecewise continuous and impulsive inputs acting on a Bounded Input Bounded State (BIBS) stable closed loop system. This, in turn, provides a separation between the robust stability and robust performance control problems. The developed methodology provides clear guidelines for steady-state and transient performance optimization and allows for parameter scheduling and multiple model controller adjustment techniques to be utilized with no stability concerns. The results are illustrated for various systems including contact-based robotic manipulation and Atomic Force Microscope (AFM) based nano-manipulation.; by Khalid El Rifai.; Thesis (Ph. D.)--Massachusetts Institute of Technology...

‣ Ductile fracture modeling : theory, experimental investigation and numerical verification

Xue, Liang, 1973-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 228 p.
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The fracture initiation in ductile materials is governed by the damaging process along the plastic loading path. A new damage plasticity model for ductile fracture is proposed. Experimental results show that fracture initiation in uncracked ductile solids is sensitive to the hydrostatic pressure and is dependent on the Lode angle. The damage plasticity model is established on a "cylindrical decomposition" system accounting for the pressure dependence, Lode angle dependence and the non-linear damage rule. Two internal variables are adopted to quantify the evolution of material properties. One is the plastic strain and the other is so-called damage variable. The joint effects of pressure and Lode angle define a fracture envelope in the principal stress space. Plastic deformation induced damage is expressed by an integral of the damage rate measured at current loading and deformation status with respect to the fracture envelope. A non-linear damage rule is proposed to characterize the damage accumulation with respect to the plastic strain. Furthermore, a damage related weakening factor is adopted to describe the material deterioration.; (cont.) Aluminum alloy 2024-T351 is selected and a series of experiments have been conducted to determine the necessary material parameters for the description of the mechanical and damage properties. The numerical integration procedure is presented. The proposed model is numerically implemented into an explicit code. Simulations were performed and the results show good agreement with the experimental data. Several representative load conditions are also modeled. These simulations illustrate realistic crack patterns. In addition to the damage plasticity model...

‣ Applied high resolution digital control for universal precision systems

Gawlik, Aaron John
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 225 p.
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This thesis describes the design and characterization of a high-resolution analog interface for dSPACE digital control systems and a high-resolution, high-speed data acquisition and control system. These designs are intended to enable higher precision digital control than currently available. The dSPACE system was previously designed within the PMC Lab and includes higher resolution A/D and D/A interfaces than natively available. Characterization on the custom A/D channel demonstrates 20.1 effective bits, or a 121 dB dynamic range, and the custom D/A channel demonstrates 15.1 effective bits, or a 91 dB dynamic range. This compares to a 15.7 effective bits on the A/D dSPACE channel and 12.3 effective bits on the D/A dSPACE channel. The increased resolution is attained by higher performance hardware and oversampling and averaging the A/D channel. The sampling rate is limited to 8 kHz. The high-resolution, high-speed data acquisition and control system can sample two A/D channels at 2.5 MHz and display/save an acquired one second burst. The A/D channel is characterized at 109 dB dynamic range with a grounded input and 96 dB dynamic range, or 0.74 nm RMS over a 50 [mu]m range, with a fixtured capacitive probe. Acquisition at 2.5 MHz and closed-loop control at 625 kHz sampling rate is implemented on a National Instruments FPGA. The A/D circuit was designed and built on a custom printed circuit board around the commercially available AD7760 sigma-delta converter from Analog Devices and includes fully differential ±10 V inputs...

‣ Landmine removal : technology review and design proposal as pertaining to humanitarian demining with a focus on locomotion across soft terrain

Poteet, Amanda N
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 42 p.
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A study into the field of humanitarian landmine removal was conducted; with significant attention devoted to an in depth review of existing removal technologies, as well as alternative detection methods. A design proposal was also presented in addition to the technology review. The design is for an autonomous robot which is capable of working in conjunction with canine demining units, with further implications for the development of a robotic unit capable of landmine detection. Further investigation was done into the possible modes of robotic locomotion, resulting in the determination that mechanical legs, as opposed to wheels, are the better choice when traversing across soft terrain.; by Amanda N. Poteet.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.; Includes bibliographical references (p. 42).

‣ Concept to prototype : musical instrument effect pedal : an exercise in design and manufacturing; Musical instrument effect pedal : an exercise in design and manufacturing

Molina, Homar, Jr
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 34 leaves
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It was the goal of this thesis to use skill sets and manufacturing methods discussed or introduced but not practiced in the undergraduate curriculum for mechanical engineers to create a working prototype of a musical instrument effect pedal. Specifically these skills include post-failure metallurgical examinations and circuit board design, and the manufacturing methods include metal forming (not cutting) with a lathe and sand casting. A musical instrument effect was chosen because it is a simple device with relatively simple circuitry, yet it still poses issues of system integration and design problems on multiple fronts. A typical design process was followed. However, in choosing manufacturing processes typical factors were examined (cost, rate, quality, etc.) as well as the stipulation that the process chosen must have been practiced before in the curriculum, forcing the designer to encounter different challenges and learn the detailed workings of an unfamiliar process. Finally recommendations concerning assembly and process modifications for mass production were given in light of the experience gained from building the prototype.; by Homar Molina, Jr.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering...

‣ Rapid prototyping of rapid prototyping machines

Moyer, Ilan Ellison
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 50 leaves
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Rapid prototyping tools empower individuals to create almost anything. Unfortunately, these tools are still far too expensive for personal ownership. The do-it-yourself community has responded with a slew of home-made rapid prototyping machines, but development times are slow because of the complexity of the necessary control system and the need to design the mechanical elements from scratch. This thesis seeks to address both of these issues. A control system is developed which treats the machine as a distributed Internet Zero network controlled by a software virtual machine with the benefits of simplified configuration and greater flexibility. A low cost circuit board milling machine, built as the test bed for this distributed controller, is described in detail. Finally, a parametrically designed XY table is introduced as a prototype for a universal machine axis and a first step towards the creation of reusable machine designs. These contributions will hopefully aid in accelerating the development of new rapid prototyping machines.; by Ilan Ellison Moyer.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.; Includes bibliographical references (leaf 50).

‣ Hip function characterization in the sagittal plane with varying gait speed

Cerda, Erika R. (Erika Rocio)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 22 p.
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The function of the human hip joint during the stance phase of walking can be characterized with a configuration of simple mechanical elements. This combination of elements is capable of providing general hip behavior in the sagittal plane. Data was collected from two healthy, young subjects who walked at slow, normal and fast gait speeds. The hip can be modeled with a torque actuator and two independent, linear torsional springs, which are activated at different times during the stance phase of gait. The activation times consistently identify gait cycle events across all three gait speeds. The first spring operates during the single limb stance of the gait cycle. The second spring is actuated during second double support, in the pre-swing phase. The springs effectively reduce the amount of work an unaccompanied torque actuator would have to exert in order to reproduce the hip gait pattern.; by Erika R. Cerda.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.; Includes bibliographical references (p. 22).

‣ Mechanics of periodic elastomeric structures with varying void volume fraction and thin-film coating

Kozlowski, Michael C. (Michael Charles)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 45 leaves
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Super-elastic periodic structures possess special mechanical, photonic, phononic, and topological properties, making them particularly relevant for application at the micro and nano length scales. This study examines the behavior of such materials in two and three dimensions when void volume fraction is varied and a thin-film coating is incorporated. Computer modeling was used to predict and understand the mechanics of the transformation behavior; results showed that three-dimensional specimens behaved like their 2D counterparts and that addition of the film influenced structural transformation. Specifically, increasing volume fraction brought pattern transformation at lower values of stress and strain. Conversely, film presence postponed transformation and made it a gradual process. The film also showed considerable out-of-plane displacement and created a channel which spanned the structure. Out-of-plane motion and pattern transformation were verified experimentally by loading a 90 x 110 mm specimen to a strain of about 13% using a testing fixture. Although conducted in the macroscopic domain, experimental behavior can be expected at smaller length scales. The transformations and the surface topology alterations are reversible upon unloading...

‣ A study of the stretch-induced softening behavior of particle filled elastomers/

Greb, Andrea (Andrea L.)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 61 leaves
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Elastomers are able to undergo relatively large deformations in an elastic manner, which makes them the material of choice for a wide range of applications. In some cases, filler particles, such as carbon black, are added to the elastomer to alter the mechanical behavior when subjected to different loading conditions. When subjected to cyclic loading conditions, elastomers undergo stress-induced softening, known as the Mullins effect, and this softening behavior is influenced by the amount of filler particle present. The softening is considered to be an evolution of the soft and hard domain microstructure of the material, with the effective soft domain increasing with stretch. In this study, finite element analysis will be used to understand the softening behavior of particle reinforced elastomers. The softening behavior of the parent elastomer will be modeled using a constitutive model proposed by Qi and Boyce (2004). Nonlinear finite element analysis using the ABAQUS code was used to model elastomers with various volume fractions of filler particles, and the stress-strain behavior of the composite and evolution of the soft domain within the matrix is computed. The addition of filler particles was found to increase the overall stiffness of the elastomer...

‣ Silicon cast wafer recrystallization for photovoltaic applications

Hantsoo, Eerik T. (Eerik Torm)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 122 p.
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Current industry-standard methods of manufacturing silicon wafers for photovoltaic (PV) cells define the electrical properties of the wafer in a first step, and then the geometry of the wafer in a subsequent step. The geometry is typically defined by a combination of grinding and abrasive wire sawing. While mature, these processes remain slow and wasteful of raw materials. As the PV industry scales to meet increasing global demand for renewable energy, new processes for creating wafers must be explored. This project sets out to enable high-speed casting of individual wafers, by developing a zone recrystallization process to improve rapid-cast wafers of low electrical quality. In the process, individual wafer geometry is defined in an upstream high-speed casting step with little regard to electrical quality. Subsequently, the electrical properties (through grain structure, dislocation density, and segregation of impurities) are optimized by zone recrystallization. The work outlined in this report documents the development of a custom, high- purity zone recrystallization furnace; an encapsulation mechanism for molten wafers; a mechanical fixturing scheme to preserve the planarity of recrystallized samples; and a release layer to prevent adhesion of the wafer to support structures. Further...

‣ Supply chain management in the dry bulk shipping industry

Nicholson, Bryan E. (Bryan Edward)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 85 leaves
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This paper is intended to show the importance of supply chain management in the dry-bulk shipping industry. A hypothetical company, the Texas Grain and Bakery Corporation, was created. The values and calculations used are artificial but representative of the industry. A well defined fleet analysis of Texas Intercoastal Transport's vessels and supply chain infrastructure show that an increase in productivity and profitability are possible with proper implementation. A systems approach of tying together the subsidiaries of Texas Grain and Bakery is used. This analysis is broken into seven sections: (1) Overview of the Systems Approach, which breaks down the seven step process. (2) Establishing a Baseline, which shows an annualized view of cargo movement of the core trade based on the first half of 2005. (3) Analysis of "Ideal" Allocation of Current Fleet, which defines assumptions used in the model and proposes a core trade fleet. (4) Analysis of Intermediate Fleet Allocation, which is a fleet analysis executable within the next 18 months.; (cont.) (5) Analysis of Long-Term Fleet Allocation, which is a fleet analysis executable around 2009. Two new-build vessels are added into the core trade along with sharply increasing the amount of grain moved. (6) Analysis of Delays...