Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 79). / Due to the global expansion of Company A's supply chain network, it is becoming more vulnerable to many disruptions. These disruptions often incur additional costs; and require time to respond to and recover from these disruptions. The base paper supply chain was identified as the most vulnerable area of the Company A Jurong and South & Southeast Asia Cluster supply chain; and a multi-stage supply chain was proposed to improve the supply chain's resilience. A statistical model was constructed to select the optimal location of the central warehouse for the proposed multi-stage supply chain. After evaluating the resilience to disruptions and the cost effectiveness of supply chains, the multi-stage supply chain with central warehouse in Tanjung Pelepas, Malaysia was found to be overall most resilient and cost effective among all the supply chains. It also incurs a lower additional cost in the event of a disruption such as changes in exchange rates and demand forecast accuracy, fuel price fluctuation, labor cost increase and shipping disruptions. As a result, establishing this multistage supply chain is recommended. / by Jingxia Yang. / M.Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000. / Includes bibliographical references (p. 45-46). / by Felix F. AuYeung. / S.M.

Thesis: S.B., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 51-52). / This thesis describes two aspects of a project designed to understand the liquid-vapor interface in microstructured heat exchangers. The two aspects include: design and fabrication of a custom vacuum chamber faceplate and the investigation of the liquid meniscus shape on microstructured devices. The faceplate for the vacuum chamber consisted of two metal components that serve to house and seal a viewport. Addition of the viewport to the chamber was of interest so that experimentation within a pure environment could be conducted.The second component of this project was to map the meniscus profile of water on three different device geometries under various conditions by laser interferometry. The first experiment was a transient study where a droplet of water fully evaporated from the surface. The purpose was to determine how the profile changes as evaporation progresses. As evaporation occurs a more curved meniscus is established within the liquid which causes a greater capillary pressure. The second experiment was a steady state study with the samples partially submerged in water. This aimed to determine the profile that arises when evaporation is balanced by fluid replenishment. The profile that arises after the first several microstructure unit cells remains constant for the remainder of the microstructured region of the sample and the meniscus has the highest curvature near the fluid front, indicating a higher capillary pressure. The final experiment was varying heat applied to the surface. The aim was to determine how the applied heat flux changes the steady state profile. With higher temperature more fluid evaporates from the surface, resulting in an increase of meniscus curvature with increased temperature. / by Edgardo Farias. / S.B.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007. / Includes bibliographical references (leaves 46-47). / In Haiti, most families have traditionally relied on wood and wood-derived charcoal as their primary fuel source for indoor cooking. This resource has proven to be unsustainable, however, as over 90% of the Haitian countryside has already been deforested and wood is now in low supply. As a poor country, importing fuel is not a viable option and thus, the ability to utilize renewable energy sources is critical. The work of the Edgerton Development Lab, under the guidance of Amy Smith, has developed a process utilizing an oil drum kiln to convert readily available agricultural waste from sugarcane, known as bagasse, into clean burning charcoal briquettes. In order to improve the efficiency of the existing oil drum kiln, this research will explore the design of a brick kiln that is relevant for the social dynamic of developing countries, inexpensive to manufacture and simple to operate. By defining the best system applicable to the Haitian context, this research will enable the efficient production of charcoal. This research will also define the shape of the chamber and the steps involved in the conversion process, enabling Haitians to make use of their natural resources to address a critical energy need. In addition, the enhanced energy efficiency will reduce the production time of the charcoal briquettes. Lastly, this research will explore how this technology can be best integrated into the existing culture and lifestyle of the Haitian community and propose a strategy for community participation. / by Etienne Clement Toussaint. / S.B.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. [110]-114). / This work develops a practical approach to explore rough environments when time is critical. The harsh environmental conditions prevent the use of range, force/torque or tactile sensors. A representative case is the mapping of oil wells. In these conditions, tactile exploration is appealing. In this work, the environment is mapped tactilely, by a manipulator whose only sensors are joint encoders. The robot autonomously explores the environment collecting few, sparse tactile data and monitoring its free movements. These data are used to create a model of the surface in real time and to choose the robot's movements to reduce the mapping time. First, the approach is described and its feasibility demonstrated. Real-time impedance control allows a robust robot movement and the detection of the surface using a manipulator mounting only position sensors. A representation based on geometric primitives describes the surface using the few, sparse data available. The robustness of the method is tested against surface roughness and different surrounding fluids. Joint backlash strongly affect the robot's precision, and it is inevitable because of the thermal expansion in the joints. Here, a new strategy is developed to compensate for backlash positioning errors, by simultaneously identifying the surface and the backlash values. Second, an exploration strategy to map a constraining environment with a manipulator is developed. To maximize the use of the acquired data, this work proposes a hybrid approach involving both workspace and configuration space. The amount of knowledge of the environment is evaluated with an approach based on information theory, and the robot's movements are chosen to maximize the expected increase of such knowledge. Since the robot only possesses position sensors, the location along the robot where contact with the surface occurs cannot be determined with certainty. Thus a new approach is developed, that evaluates the probability of contact with specific parts of the robot and classifies and uses the data according to the different types of contact. This work is validated with simulations and experiments with a prototype manipulator specifically designed for this application. / by Francesco Mazzini. / Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000. / Includes bibliographical references (leaves 63-64). / by George Costa. / S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1988. / Includes bibliographical references. / by Andrew Glenn Ziegler. / M.S.

Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 59-60). / Access to surgical care for people in remote settings and/or developing countries is limited: 30% of the world's population receives 75% of major operations [1]. In developing countries, up to a third of patients acquire a surgical site infection (SSI), which is nine times more likely than in developed countries [2]. An estimated 85,500 cases of HIV and hepatitis are contracted by obstetrical/gynecological providers every year, and 90% of those cases are the result of treating patients living in poverty. SurgiBox aims to address these issues by providing a portable, sterile operating environment for use in austere settings. Not only are patients protected from environmental hazards through the use of SurgiBox, but medical personnel are also shielded from patient fluids, blood, and aerosols. SurgiBox consists of a clear, disposable plastic enclosure that is adhered to the patient's surgical site and inflated with filtered air. Long gloves, similar those used in a glovebox, are integrated into the enclosure and used by the medical personnel to perform the surgery. Surgical instruments are sterilized before the surgery and are placed inside the enclosure prior to the procedure, but materials, or even a baby in the case of a cesarean section, can be passed in or out of the sterile field during the procedure through a resealable port. Particle count testing inside the enclosure shows that particle counts could be maintained at less than 25% of operating room standards for particles greater than 0.5 microns (OR standard: less than 83,000 particles/m3)and 0.3 microns (OR standard: less than 1,000,000 particles/m 3 ). / by Sally A. Miller. / S.M.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1993. / Includes bibliographical references (leaf 50). / by Sean W. LaHousse. / B.S.

Thesis: S.M. in Naval Architecture and Marine Engineering, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 121-123). / In ship design projects, it is of utmost importance to investigate a wide range of options during the concept design phase in order to determine which one best suits to the requirements. Although, keeping the concept design phase shorter in order to be competitive in the market is as important. The chances for a shipyard to win a contract would surely increase with a proposed design whose performances are demonstrated through a systematic evaluation of alternative solutions. However, the number of the design alternatives is inversely proportional to the time span of concept design for each alternative. The detailed evaluations at this stage can only be performed with CFD (Computational Fluid Dynamics) and FE (Finite Element) tools, and both require a complete representation of the ship hull geometry. So, only having a faster hull form generation tool would enable the designer to evaluate more options. It is possible to achieve rapid geometry generation through fully parametric modeling. Fully parametric hull modeling is the practice of creating the entire hull shape definition only from form parameters, without the need for offset data or predefined lines plan. In this thesis a fully parametric modeling tool, PHull, is developed using Java programming language for rapid geometry generation of high speed displacement monohulls, in order to be used in hydrodynamic optimization process. The results from the validation cases, FFG-7 and ATHENA Model 5365, are presented. / Mert Timur. / S.M. in Naval Architecture and Marine Engineering