9,209 research outputs found

    A strategy for reducing turnaround time in design optimization using a distributed computer system

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    There is a need to explore methods for reducing lengthly computer turnaround or clock time associated with engineering design problems. Different strategies can be employed to reduce this turnaround time. One strategy is to run validated analysis software on a network of existing smaller computers so that portions of the computation can be done in parallel. This paper focuses on the implementation of this method using two types of problems. The first type is a traditional structural design optimization problem, which is characterized by a simple data flow and a complicated analysis. The second type of problem uses an existing computer program designed to study multilevel optimization techniques. This problem is characterized by complicated data flow and a simple analysis. The paper shows that distributed computing can be a viable means for reducing computational turnaround time for engineering design problems that lend themselves to decomposition. Parallel computing can be accomplished with a minimal cost in terms of hardware and software

    Processing a Workmen\u27s Compensation Case in Ohio

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    The Workmen\u27s Compensation system, which has been a part of Ohio law since May 31, 1911, represents a sharp departure in concept from the earlier methods of redressing work injuries. Under Workmen\u27s,Compensation, neither the negligence of the employer nor that of, the employee plays any part in the determination of the employee\u27s entitlement to the stated benefits. It is the fact of injury sustained in the course of and arising out of employment which is critical

    Innate Immunity in Type 2 Diabetes Pathogenesis: Role of the Lipopolysaccharide Signaling Cascade: A Dissertation

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    Once seen as a disease of wealthy nations, type 2 diabetes mellitus is now showing unprecedented growth throughout the world, fueling increases in microvascular and macrovascular complications. A compelling and growing body of evidence suggests that glucose intolerance and insulin resistance, hallmarks of the diabetic patient, may be driven by chronic inflammation. In particular, a predominance of visceral fat has been associated with enhanced inflammatory cytokine secretion that may contribute to enhanced risk of diabetes and comorbid cardiovascular disease in these individuals. As a function of its potency and wide environmental and biological distribution, we hypothesized that bacterial lipopolysaccharide (LPS, also known as endotoxin) may promote adipose inflammation and concomitant metabolic dysfunction. Indeed, expression of the LPS receptor CD14 is enhanced on visceral adipocytes of ob/ob mice, paralleling enhanced IL-6 secretion ex vivo. Furthermore, rosiglitazonefed ob/obmice demonstrated a reduction in CD14 that coordinated with diminished IL-6 secretion, suggesting a basis for the touted anti-inflammatory effects of this commonly employed type 2 diabetes medication. Mice deficient in components of the LPS signaling cascade, namely CD14, TLR4, and MyD88, yielded adipocytes with markedly attenuated IL-6 secretion, corroborating the central importance of LPS in adipocyte inflammation and supporting the role of this signaling pathway in depot-specific inflammation. Despite the prominent role of LPS signaling in adipocyte inflammation, CD14-, TLR4-, and MyD88-deficient mice failed to show resistance to diet induced obesity. Surprisingly, cd14-/- and tlr4-/- mice had marked glucose intolerance without alteration in total weight or adipose accumulation. In contrast, myd88-/- mice revealed minor glucose intolerance only with high fat diet challenge at an advanced age despite being overtly obese. In cd14-/- and tlr4-/-, but not myd88-/-, mice, an exaggerated rebound to hypoglycemia was associated with enhanced norepinephrine secretion, which could be abrogated by the adrenergic β-blocker propranolol. The overlay of these mouse models reveals a divergence of phenotypes that demonstrate LPS signaling disruption may lead to glucose intolerance and insulin resistance in part due to enhanced sympathoadrenal tone, uncovering an essential role of innate immunity in physiological stress and its impact upon glucose homeostasis

    Space station mobile transporter

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    The first quarter of the next century will see an operational space station that will provide a permanently manned base for satellite servicing, multiple strategic scientific and commercial payload deployment, and Orbital Maneuvering Vehicle/Orbital Transfer Vehicle (OMV/OTV) retrieval replenishment and deployment. The space station, as conceived, is constructed in orbit and will be maintained in orbit. The construction, servicing, maintenance and deployment tasks, when coupled with the size of the station, dictate that some form of transportation and manipulation device be conceived. The Transporter described will work in conjunction with the Orbiter and an Assembly Work Platform (AWP) to construct the Work Station. The Transporter will also work in conjunction with the Mobile Remote Servicer to service and install payloads, retrieve, service and deploy satellites, and service and maintain the station itself. The Transporter involved in station construction when mounted on the AWP and later supporting a maintenance or inspection task with the Mobile Remote Servicer and the Flight Telerobotic Servicer is shown

    Economics of Using On-farm Reservoirs to Distribute Diverted Surface Water to Depleted Ground Water Areas of the Southern Mississippi Valley Region

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    Rapid ground water depletion has become a significant problem for parts of the Southern Mississippi River Valley. In 1997, the Arkansas Soil and Water Conservation Commission (ASWCC) declared six counties in the Grand Prairie of Arkansas critical ground water areas. A proposed solution to the ground water depletion problem in this region is to divert surplus flows from the White River by a canal system to the farmer stakeholders. To make the system work, on-farm reservoirs will be needed to store and manage the diverted surface water for crop irrigation use during the growing season

    Study of the Properties of Coarse Aggregates

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    Research Project C-22 is an investigation of the geologic aspects of limestone aggregate that might cause failure if used in highway construction. This represents work being carried on at the Highway Materials Research Laboratory in Lexington. The end point of this work is to determine the cause or causes of failure and provide a test that will delete faulty materials from construction work. In order to evaluate the engineering aspect of the author\u27s work, a study ef the physical tests of these same aggregates is to be made. A correlation between Laboratory Analysis and performance Surveys of these same aggregates in roads should be sufficient to make pertinent observations. Limestone varies in any and all proportions of its basic constituents, with the introduction of some new minerals from time to time. As defined, limestone should be composed of calcium carbonate plus some small amount of impurities. The variation in amount and types of impurity give a limestone its characteristics and this variation is so unique that very rarely will two limestones be identical. The variation in minerals is complex, inasmuch as two different minerals having the same elements, may have entirely different reactions to any influence brought upon them. As to the limits set on the name limestone , the presence of 50% carbonate material should assign a rock as limestone. A chemical analysis, although helpful, will not be a positive criterion as the analysis tells only the compounds present and not the way in which they are combined. It seems a reasonable hypothesis that the impurities present are the dominant agents in any failure of limestone aggregate and a careful comparative study of these impurities should show whether the premise is well founded. This, then, is the main objective of the study

    A Study of the Properties of Coarse Aggregates

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    Research Project C-22 is an investigation of the geologic aspects of limestone aggregate that might cause failure if used in highway construction, as reported earlier. As the study was to be approached from a new standpoint, it was allowed to mature along significant lines. At present a working plan has been adopted and is shown here in some detail

    Distributed computer system enhances productivity for SRB joint optimization

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    Initial calculations of a redesign of the solid rocket booster joint that failed during the shuttle tragedy showed that the design had a weight penalty associated with it. Optimization techniques were to be applied to determine if there was any way to reduce the weight while keeping the joint opening closed and limiting the stresses. To allow engineers to examine as many alternatives as possible, a system was developed consisting of existing software that coupled structural analysis with optimization which would execute on a network of computer workstations. To increase turnaround, this system took advantage of the parallelism offered by the finite difference technique of computing gradients to allow several workstations to contribute to the solution of the problem simultaneously. The resulting system reduced the amount of time to complete one optimization cycle from two hours to one-half hour with a potential of reducing it to 15 minutes. The current distributed system, which contains numerous extensions, requires one hour turnaround per optimization cycle. This would take four hours for the sequential system
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