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Mechanical Engineering - Master's degree

Mostrando recursos 1 - 20 de 3.426

  1. Symbolic and analogic command hardware for computer-aided manipulation.

    Verplank, William Lawrence
    Thesis (M.S.)--Massachusetts Institute of Technology. Dept. of Mechanical Engineering, 1967.

  2. Evaporation from nanoporous membranes

    Wilke, Kyle (Kyle L.)
    Cooling demands of advanced electronics are increasing rapidly, often exceeding capabilities of conventional thermal management techniques. Thin film evaporation has emerged as one of the most promising thermal management solutions. High heat transfer rates can be achieved in thin films of liquids due to a small conduction resistance through the film to the evaporating interface. In this thesis, we investigated evaporation from nanoporous membranes. The capillary wicking of the nanopores supplies liquid to the evaporating interface, passively maintaining the thin film. Different evaporation regimes were predicted through modeling and were demonstrated experimentally. Good agreement was shown between the predicted and...

  3. Investing in quality : identifying the true value of advanced weld inspection technology

    Buelsing, Michael T
    The quality of Caterpillar's welds is becoming increasingly important as their equipment is made leaner with the goals of increased performance, lighter weight and lower unit cost. Due to the inherently variable nature of arc welding, non-destructive weld evaluation is critical to ensure that welding processes remain in control, and that defective parts are quarantined and repaired before being released downstream. The "conventional" ultrasonic weld inspection technology in use at present has several limitations: -- Areas within common joint configurations cannot be adequately inspected due to geometry constraints; -- Discontinuity evaluation requires subjective real-time human interpretation by highly trained operators;...

  4. Design for automation in manufacturing systems and processes

    Ezolino, Juan Stefano
    The Widget' industry has changed significantly over the last 20 years. Although Company A benefited from their historically strong market position for a long time, the market share of widgets has, at this point, been evenly divided between Company A and Company B. There is therefore market pressure for Company A to reassess the way it does business to be more competitive. Automation initiatives in the Widget industry have historically been slow to be implemented, and there has been hesitation to change the way widgets and their parts are designed and manufactured due to the complexity of the widget product....

  5. Supply chain network strategy for consumer medical device introduction

    Haidar, Samer, S.M. Massachusetts Institute of Technology
    This thesis presents an optimization framework to model the trade-offs in strategic supply chain decision-making for a new product introduction in a real-world setting. The focus of the thesis is on a consumer medical device that Johnson & Johnson's Calibra business will launch in the future. As with any new product introduction, the launch exposes the J&J business to risk and uncertainty. We develop a mixed-integer optimization model to guide the optimal design of a global consumer medical device supply chain network comprising component suppliers, assembly facilities, sterilizers, and distribution centers. The model evaluates strategic decisions over a seven-year time...

  6. Quality control improvement in global apparel sourcing

    Heath, Michael Lindsey
    This project addressed challenges within the quality management process of one of the operating groups of Li & Fung. The primary goals were improved product quality and reduced quality control costs. The operating group works with thousands of factories across the world, producing a large variety of apparel and textile products. The industry trend of fast fashion, with small order sizes and shorter lead times, has placed considerable burden on the limited quality control resources. Understanding the current state of the quality management process was the first project step, and this was accomplished through factory visits and interviewing workers. The...

  7. Identifying opportunities to reduce emergency service calls in hematology manufacturing using statistical methods

    Fox, Marshall Edward
    The main goal of this project is to identify opportunities to improve the reliability of the DxHTM product line, an automated hematology instrument for analyzing patient blood samples. The product was developed by Beckman Coulter Diagnostics, a division of a Danaher operating company with principal manufacturing and support operations based near Miami, Florida. A critical business metric used to reflect reliability is the Emergency Service Call (ESC) rate. An ESC for an instrument is defined as the number of unscheduled, on-site technician visits during the one year warranty period. Though Beckman Coulter already deploys an extremely robust quality control system,...

  8. Improving outpatient non-oncology infusion through centralization and scheduling heuristics

    Marshall, Adam Ryan
    The use of highly effective intravenously infused specialty drugs has increased significantly over the past two decades as they have led to dramatic improvements in patients' quality-of- life. At Massachusetts General Hospital, these drugs are administered in ten independent outpatient clinics. While some clinics only need to offer sporadic treatments and have low utilization of resources, other clinics find patient access is severely limited due to high utilization, poor scheduling practices, and inadequate staffing. This thesis describes methods to increase patient access to infusion while improving resource utilization. Underlying this improvement is a specially developed scheduling algorithm that smooths chair...

  9. Advancing lean implementation for next generation biomanufacturing operations

    Jensen, Joshua David
    Amgen Singapore Manufacturing (ASM) is a "first of its kind" commercial biomanufacturing site, incorporating myriad innovations including a full scale single-use bioreactor production model. Known internally at Amgen as Next Generation Biomanufacturing, this model will be the future of drug substance manufacturing at Amgen Inc. With the creation of Next Generation Biomanufacturing, significant changes are required within site operations including how Lean principles and methodologies are implemented and utilized in this model. An opportunity had been identified to determine an effective Lean implementation for ASM in order to capitalize on its full potential and set the Lean strategy for future...

  10. Glass siliconization process characterization for insulin delivery device performance

    Schacherl, Jeffrey D
    Baked-in siliconization of glass cylinders, primary insulin containers, is a manufacturing process that is critical to the performance of drug delivery devices. Delivery devices are evolving and placing additional burden on production processes. Variability in siliconization and baking processes affects the resulting friction characteristics that are related to device performance criteria such as injection time and velocity, which are critical to the patient experience. The principal objective is to better characterize the performance of siliconized and baked glass, enabling improvement of device injection performance. A controlled study was conducted in order to strip away extraneous variables and enhance experimental control....

  11. Artificial intelligence opportunities and an end-do-end data-driven solution for predicting hardware failures

    Orozco Gabriel, Mario
    Dell's target to provide quality products based on reliability, security, and manageability, has driven Dell Inc. to become one of the largest PC suppliers. The recent developments in Artificial Intelligence (AI) combined with a competitive market situation have encouraged Dell to research new opportunities. Al research and breakthroughs have risen in the last years, bringing along revolutionary technologies and companies that are disrupting all businesses. Over 30 potential concepts for Al integration at Dell Inc. were identified and evaluated to select the ones with the highest potential. The top-most concept consisted of preventing in real time the failure of hardware....

  12. Operations and strategy improvement : form and functionality optimization of an assembly system design

    Falvella, Joseph M
    The purpose of this thesis is to show a systematic approach to identify bottlenecks and "pain points" in the operations of a manufacturing firm, to identify the root causes of such problems, and explore viable solutions. Furthermore, the purpose of this thesis is to serve as a strategic tool for implementation of the proposed solutions. This thesis covers the entire mapping of the manufacturer's current facility, the physical layout as well as the material and process flow, and includes a proposal for a new streamlined layout that optimizes floor space, reduces work in progress, and ultimately increases efficiency in the...

  13. An experimental study of the one Atmosphere Diving Suit (ADS) and data analysis of military diving

    Colgary, James J., Jr
    The Atmospheric Diving Suit (ADS) is a one-man submarine with moveable, humanlike appendages with internal pressure maintained at one atmosphere. This precludes the possibility of common diving related illnesses while giving the operator an increased depth of operation compared to traditional diving systems. The ADS provides additional capability for industries and militaries around the world, but is not without its own unique challenges and limitations. Current ADS maneuverability, specifically that associated with joint rotation, lacks natural movement and range of motion, rendering most normal underwater tasks more challenging and taxing on the operator. Concerns about the lack of maneuverability and...

  14. Design and testing of a pan-tilt mechanism for severe environments

    Mills, Nathan (Nathan Matthew)
    U.S. Navy ships have non-rotating radar and electronic warfare devices installed, which are often supported and trained by two-axis gimbals. In current shipboard solutions the payloads are often placed on a platform above the gimbal drive train, which results in high moment loads on drive components during a wave impact. As the payloads grow in size, the moment grows as well, and the current gimbal design is insufficient to support some payload geometries. This thesis presents a novel design for a low-mass two-axis machine that supports large payloads without large impact moments by locating the center of action along the...

  15. An experimental study of the human interface with one atmosphere diving suit by appendages

    Wilkins, Christopher Michael
    This experimental study of the human interface with an Atmospheric Diving Suit (ADS) develops a method for quantitatively evaluating how the pilot interacts with the suit's appendages to inform design improvements and to provide a baseline of joint performance for existing technologies. An Atmospheric Diving Suit is a one person anthropomorphic pressure vessel, with manually operated maneuverable appendages, capable of carrying a diver to great depths in the sea while maintaining the internal cabin pressure at one atmosphere (14.7 psi). Commercial ADS are used regularly around the world in offshore industries, and military ADS are used by a large number...

  16. Integrating Model Based Engineering and trade space exploration into naval acquisitions

    Stepanchick, Justin
    The Navy Acquisition force is faced with designing, procuring, and managing some of the most complex systems and technologies imagined. Balancing a shrinking and fickle budget environment with a program that has dynamic requirements and scheduling pressures only complicates this already difficult job. While developing these increasingly complex systems, major programs often face decisions without a sufficient analysis on a performance-versus-cost tradeoff. To surmount these challenges, the Navy must look at how industries excelled in similar environments. The concept of Model Based Engineering (MBE) is introduced as an approach that could move Navy Acquisition from document-centric to model-centric, enabling efficiency...

  17. Multi-attribute tradespace exploration for US Navy surface ship survivability: a framework for balancing capability, survivability, and affordability

    Walker, Johnathan C. (Johnathan Clyde)
    In a political environment of austerity, the importance of understanding the design tradeoffs for new naval ship concept designs cannot be understated. A combination of a tightened shipbuilding budget, large high-priority procurement programs, and an emphasis on affordability will require high level tradeoffs to be made in future ship programs. Understanding tradeoffs in naval ship capability and survivability for the sake of affordability early in concept ship design gives Navy leadership real options for affordable ships and reduces the likelihood of detailed design changes late in the acquisition process. In the naval ship design process capability and affordability are typical...

  18. Bragg reflector geometries for colorimetric orientation and deformation sensing

    Wing, Christopher (Christopher John)
    Propulsion systems of commercial and naval ships are typically large and expensive. They must be kept well-aligned and free of corrosion to efficiently and reliably transfer torque to a ship's propeller. Early identification of misalignment or surface corrosion is therefore crucial, making an easily deployable, reliable, lightweight system that visually indicates potential alignment and structural integrity issues desirable. This thesis demonstrates the design of a system for visual deformation and orientation indication based on naturally occurring micro-scale surface geometries that show a strong variation in their optical appearance as a function of illumination and observation directions. Specifically, the fabrication of...

  19. Modeling brake specific fuel consumption to support exploration of doubly fed electric machines in naval engineering applications

    Rowles, Jr., Michael R. , Jr
    The dynamic operational nature of naval power and propulsion requires Ship Design and Program Managers to design and select prime movers using a much more complex speed profile rather than typical of commercial vessels. The inherently reduces the overall efficiency of the plant as operated in comparison to its potential. The fuel consumption of prime movers is a multi-variable function of power demand and rotational speed. Mechanically coupled power and propulsion arrangements constrain this two degree of freedom relationship by removing the independence of the speed parameter. Fixed frequency power generation requires a constant prime mover speed that has a...

  20. Development of designer-relevant Lattice-Boltzmann Wind Field Model for urban canyons and their neighborhoods

    Chen, Tianyi, S.M. Massachusetts Institute of Technology
    Wind field analysis is one of the most important components for designers to achieve a thermally-comfortable and energy-efficient building design. Designers need a fast and relatively accurate wind field model to get integrated into the design workflow, but current platforms to work on are either costly and time-consuming conventional Computational Fluid Dynamics (CFD) tools or over-simplified data correlation factors, which makes the workflow undesirable for designers' use. In this thesis, a novel Lattice-Boltzmann Wind Field Model (LBWFM) is developed and integrated in a designer-relevant Rhino-based environment. Lattice-Boltzmann Method (LBM) is introduced as the solver due to its open-source and parallelism...

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