3,887 research outputs found

    Corporate blue : a novel presented in partial fulfilment of the requirements for the degree of Master of Arts in English, Massey University

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    My first day on the job with those nutcases, I was greeted by the loser's end of a very large handgun. Were I a more intuitive man, I could have taken that as a sign to just turn around and walk away. Leave that place and never think of it again. It would've been the wise thing to do. In my own defence however, I could point out that I didn't have a lot of options as to where I could turn. The President of the United States, among others, was pissed-off with me. And I had promised myself that I would make the best of this new situation in a new country. In time-I figured a year max-I was sure they would all forgive me back in America and let me come home

    On the use of NAND flash memory in high-performance relational databases

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    Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (p. 47-49).High-density NAND flash storage has become relatively inexpensive due to the popularity of various consumer electronics. Recently, several manufacturers have released IDE-compatible NAND flash-based drives in sizes up to 64 GB at reasonable (sub-$1000) prices. Because flash is significantly more durable than mechanical hard drives and requires considerably less energy, there is some speculation that large data centers will adopt these devices. As database workloads make up a substantial fraction of the processing done by data centers, it is interesting to ask how switching to flash-based storage will affect the performance of database systems. We evaluate this question using IDE-based flash drives from two major manufacturers. We measure their read and write performance and find that flash has excellent random read performance, acceptable sequential read performance, and quite poor write performance compared to conventional IDE disks. We then consider how standard database algorithms are affected by these performance characteristics and find that the fast random read capability dramatically improves the performance of secondary indexes and index-based join algorithms. We next investigate using logstructured filesystems to mitigate the poor write performance of flash and find an 8.2x improvement in random write performance, but at the cost of a 3.7x decrease in random read performance. Finally, we study techniques for exploiting the inherent parallelism of multiple-chip flash devices, and we find that adaptive coding strategies can yield a 2x performance improvement over static ones. We conclude that in many cases flash disk performance is still worse than on traditional drives and that current flash technology may not yet be mature enough for widespread database adoption if performance is a dominant factor. Finally, we briefly speculate how this landscape may change based on expected performance of next-generation flash memories.by Daniel Myers.S.M

    The Role of Osteopontin in Vascular Remodeling

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    Chronic obstructive vascular disease is a major contributor to mortality in developed nations. The pathology typically involves neointima formation accompanied by vascular remodeling in the presence of inflammation. The disease can be modeled in animals with the response to a direct injury of the vasculature. This text describes a project examining the role of osteopontin (OPN) in vascular remodeling. The projectis goal was to mechanistically describe the contribution of OPN to the vascular injury response. The hypothesis that the presence of OPN affects the formation of neointima and constrictive remodeling associated with vascular injury was addressed using the strategy of comparing the remodeling response induced by carotid artery ligation of wild type mice to mice with a null mutation in the geen encoding OPN at time points known to be critical to lesion development. OPN null mutant mice were compared to wild type mice before and after carotid artery ligation. As substantial variation is observed in the response to carotid artery ligation, the variance was analyzed for potential contributing variables. Distance from the site of ligation was shown to be a significant predictor, and data was analyzed using curvilinear regression. Prior to ligation, OPN null mice had increased heart rate, lower blood pressure, and increased circulating lymphocytes compared to wild type mice. OPN null vessels also demonstrated greater compliance accompanied by a loosely organized collagen network. Following carotid artery ligation, significant differences were also found in the remodeling response of OPN null animals. At 4 days after ligation, leukocyte adhesiodinvasion was diminished by 10-fold in OPN null mice compared to wild type. At 14 days following ligation, the ligated arteries of OPN null mice had smaller neointimal lesions, but greater constrictive remodeling compared to wild type mice, resulting in similar lumen area. Continued remodeling resulted in a similar morphological phenotype in both groups at 28 days. These data show that endogenous OPN regulates normal vascular physiology, and contributes to the vascular remodeling response by regulating vascular compliance and the inflammatory response

    The House Price Impacts of Corporate Headquarter Relocations

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    This project examines the house price impacts of corporate headquarter relocations. Corporate relocations potentially impact house prices through the increase or decrease in local economic activity that results from the relocation event. Using a difference in differences approach, I compare the impacts of a relocation on a metropolitan statistical area (MSA) house prices to similar metropolitan statistical areas house prices that have not seen relocations by corporations. Local house price indexes from the Federal Housing Finance Agency (FHFA) are used to examine changes in house prices at the MSA level to gauge a relocation effect. Data on the housing market characteristics from the U.S. Census Bureau is used to create a sample of comparison cities. Analysis is conducted using data before and after a relocation to analyze house prices appreciation rate impacts from a corporation’s headquarter relocation or merger during the 2000 to 2015 time period. It is expected that data will indicate a negative effect due to the exit of a firm and a boost to the local economy that receives a firm’s new headquarters

    Time Zones As Cues For Coordination: Latitude, Longitude, And Letterman

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    Market productivity is often greater, and leisure and other household activities more enjoyable, when people perform them simultaneously. Beyond pointing out the positive externalities of synchronicity, economists have not attempted to identify exogenous determinants of timing. We develop a theory illustrating conditions under which synchronicity will vary and identify three factors — the amount of daylight, the timing of television programming, and differences in time zones — that can alter timing. Using the American Time Use Survey for 2003 and 2004, we first show that an exogenous shock to time in one area due to non-adherence to daylight-saving time leads its residents to alter their work schedules to continue coordinating their activities with those of people elsewhere. With time use data from Australia, we also demonstrate the same response to a similar shock there. We then show that both television timing and the benefits of coordinating across time zones in the U.S. generally affect the timing of market work and sleep, the two most time-consuming activities people undertake. While these impacts do not differ greatly by people's demographic characteristics,workers in industries where we would expect more coordination outside of their local areas are more responsive to the effects of time zones.banking, market discipline

    Process and information integration via hypermedia

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    Success stories for advanced automation prototypes abound in the literature but the deployments of practical large systems are few in number. There are several factors that militate against the maturation of such prototypes into products. Here, the integration of advanced automation software into large systems is discussed. Advanced automation systems tend to be specific applications that need to be integrated and aggregated into larger systems. Systems integration can be achieved by providing expert user-developers with verified tools to efficiently create small systems that interface to large systems through standard interfaces. The use of hypermedia as such a tool in the context of the ground control centers that support Shuttle and space station operations is explored. Hypermedia can be an integrating platform for data, conventional software, and advanced automation software, enabling data integration through the display of diverse types of information and through the creation of associative links between chunks of information. Further, hypermedia enables process integration through graphical invoking of system functions. Through analysis and examples, researchers illustrate how diverse information and processing paradigms can be integrated into a single software platform

    Time Zones as Cues for Coordination: Latitude, Longitude, and Letterman

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    Market productivity is often greater, and leisure and other household activities more enjoyable, when people perform them simultaneously. Beyond pointing out the positive externalities of synchronicity, economists have not attempted to identify exogenous determinants of timing. We develop a theory illustrating conditions under which synchronicity will vary and identify three factors %u2014 the amount of daylight, the timing of television programming, and differences in time zones %u2014 that can alter timing. Using the American Time Use Survey for 2003 and 2004, we first show that an exogenous shock to time in one area due to non-adherence to daylight-saving time leads its residents to alter their work schedules to continue coordinating their activities with those of people elsewhere. With time use data from Australia, we also demonstrate the same response to a similar shock there. We then show that both television timing and the benefits of coordinating across time zones in the U.S. generally affect the timing of market work and sleep, the two most time-consuming activities people undertake. While these impacts do not differ greatly by people's demographic characteristics, workers in industries where we would expect more coordination outside of their local areas are more responsive to the effects of time zones.
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