1,794 research outputs found

    Etiology of glaucoma

    Get PDF

    Facility Redesign at the Systech Corporation

    Get PDF
    This senior project is a redesign of Systech’s manufacturing floor as they move to their new facility to be able to support the expected increase in customer demand. As of January 2013, Systech was working near full capacity, and because of their new product release, they expect the demand to outstrip the production capabilities of the current facility. Because of this, Systech is moving their final testing operations in San Diego to a larger building. During this transition, they have expressed interest in redesigning the current floor layout in order to maximize the productivity of their employees. To accomplish this, floor plan analysis, ergonomic design principles, and facility planning expertise are used to determine the best fit layout for the new facility. The proposed facility design takes into account a visibly clear layout, using visual management techniques, as well as clustering similar tasks to optimize resources. Measurements of the new facility were made on site with a tape measure and printed file of the general layout. Once main measurements were calculated, Google Sketchup was used to create the frame of the building. This design took into account visual management, future production expansion, and a decreased footprint. In the financial analysis of the proposed facility, the expected monthly distance savings were 25.4 miles, which can be extrapolated to an annual savings due to reduced transportation costs of approximately 2,500.Asproductionisscaled,thissavingswouldincreaseto2,500. As production is scaled, this savings would increase to 5,000+. This proposed layout design can be utilized by Systech management as a roadmap as they move forward with the production in the new facility. Ideally, the proposed facility design should be implemented to gain the most savings as operations increase in the coming months

    A Study of Factors Which Influence Type IV Sand Mix Performance

    Get PDF

    Targeted Derepression of the Human Immunodeficiency Virus Type 1 Long Terminal Repeat by Pyrrole-Imidazole Polyamides

    Get PDF
    The host factor LSF represses the human immunodeficiency virus type 1 long terminal repeat (LTR) by mediating recruitment of histone deacetylase. We show that pyrrole-imidazole polyamides targeted to the LTR can specifically block LSF binding both in vitro and within cells via direct access to chromatin, resulting in increased LTR expression

    Arrested Cracks in Nonlinear Lattice Models of Brittle Fracture

    Full text link
    We generalize lattice models of brittle fracture to arbitrary nonlinear force laws and study the existence of arrested semi-infinite cracks. Unlike what is seen in the discontinuous case studied to date, the range in driving displacement for which these arrested cracks exist is very small. Also, our results indicate that small changes in the vicinity of the crack tip can have an extremely large effect on arrested cracks. Finally, we briefly discuss the possible relevance of our findings to recent experiments.Comment: submitted to PRE, Rapid Communication

    EVA Swab Tool to Support Planetary Protection and Astrobiology Evaluations

    Get PDF
    When we send humans to search for life on other planets, we'll need to know what we brought with us versus what may already be there. To ensure our crewed systems meet planetary protection requirements-and to protect our science from human contamination-we'll need to assess whether microorganisms may be leaking or venting from our spacecraft. Microbial sample collection outside of a pressurized spacecraft is complicated by temperature extremes, low pressures that preclude the use of laboratory standard (wetted) swabs, and operation either in bulky spacesuits or with robotic assistance. Engineers at the National Aeronautics and Space Administration (NASA) recently developed a swab kit for use in collecting microbial samples from the external surfaces of crewed spacecraft, including spacesuits. The Extravehicular Activity (EVA) Swab Kit consists of a single swab tool handle and an eight-canister sample caddy. The design team minimized development cost by re-purposing a heritage Space Shuttle tile repair handle that was designed to quickly snap into different tool attachments by engaging a mating device in each attachment. This allowed the tool handle to snap onto a fresh swab attachment much like popular shaving razor handles can snap onto a disposable blade cartridge. To disengage the handle from a swab, the user performs two independent functions, which can be done with a single hand. This dual operation mitigates the risk that a swab will be inadvertently released and lost in microgravity. Each swab attachment is fitted with commercially available foam swab tips, vendor-certified to be sterile for Deoxyribonucleic Acid (DNA). A microbial filter installed in the bottom of each sample container allows the container to outgas and repressurize without introducing microbial contaminants to internal void spaces. Extensive ground testing, post-test handling, and sample analysis confirmed the design is able to maintain sterile conditions as the canister moves between various pressure environments. To further minimize cost, the design team acquired extensive ground test experience in a relevant flight environment by piggy-backing onto suited crew training runs. These training runs allowed the project to validate tool interfaces with pressurized EVA gloves and collect user feedback on the tool design and function, as well as characterize baseline microbial data for different types of spacesuits. In general, test subjects found the EVA Swab Kit relatively straightforward to operate, but identified a number of design improvements that will be incorporated into the final design. Although originally intended to help characterize human forward contaminants, this tool has other potential applications, such as for collecting and preserving space-exposed materials to support astrobiology experiments
    corecore