5,418 research outputs found
Winter Concert: Andrews University Wind Symphony & SMC Brass Band
Winter Concert: Andrews University Wind Symphony & SMC Brass Bandhttps://digitalcommons.andrews.edu/events-2015-2016/1000/thumbnail.jp
Freedom Village Concert
Village Freedom Concert - A tribute to John and Dede Howardhttps://digitalcommons.andrews.edu/events-2015-2016/1005/thumbnail.jp
STABILITY OF RIDGE-RIDGE-RIDGE TRIPLE JUNCTIONS BASED ON THE MECHANICS OF RIFT INTERACTION: THE NORTHERN GALĂPAGOS AND RODRIGUEZ TRIPLE JUNCTIONS
Although known to be kinematically stable, Ridge-Ridge-Ridge (RRR) triple junctions sometimes display a complex sequence of short-lived rifts and no direct connection between the ridges. The GalĂĄpagos Triple Junction, in the Eastern Equatorial Pacific Ocean and the Rodriguez Triple Junction, in the Central Indian Ocean, serve as end-members of stability observed as RRR triple junctions. I propose that the stability of RRR triple junctions, principally whether secondary rifts are generated or direct connection between the spreading centers is favored, can be understood based on the mechanics of crack interaction. I develop numerical models of the stress field in an elastic plate under tension, with cracks representing rifts in the vicinity of a RRR triple junction and GIS spatial analysis to demonstrate the factors that control RRR triple junction's stability. Although RRR triple junctions are kinematically stable, rift junctions are mechanically unstable, generating a rapidly evolving and complex plate boundary
Takt Time Grouping: A Method to Implement Kanban-Flow Manufacturing in an Unbalanced Process with Moving Constraints
One-piece flow and kanban/pull methods have been used to reduce WIP and speed flowtime in manufacturing flow processes; however, these methods have limitations. For example, one-piece flow does not work well when there are relatively large set-up times required between different components. One-piece flow also requires operations to be well-balanced. Unfortunately, these conditions often do not exist. The Theory of Constraints drum-buffer-rope (DBR) method is designed for unbalanced processes, and it has been shown to be effective for products with large operation time variation. However, DBR does not generally optimize flowtime and cannot handle a process with moving constraints (bottlenecks). Recognizing that there are manufacturing applications that have these limitations, we have developed a method called Takt Time Grouping (TTG) for implementing kanban-flow manufacturing when one-piece flow or DBR do not perform well. TTG combines one-piece flow, transfer-batch sizing and DBR concepts through the use of a grouping algorithm. Using a discrete event simulation model, the application of TTG, one-piece flow, DBR and a dynamic version of DBR, that moves the time-buffer and drum when it is known that constraints move (DynDBR), was investigated under varying conditions and production processes. Generalized findings of TTGâs advantages over competing methods are presented
Addressing Questions of Prehistoric Occupation Seasonality at Freshwater Mussel Shell Ring Sites in the Mississippi Delta: Applications in Carbonate Geochemistry and Zooarchaeology
Seasonality estimates based on archaeological shellfish remains have been an important component of settlement pattern reconstruction. Investigations of this nature allow researchers to place prehistoric people on the landscape at points in space at different times of the year. Many of the previous seasonality studies, however, have focused on marine species from coastal sites, with little attention given to freshwater locales, especially ones in the Mississippi Delta. To address that disparity, this study examines freshwater mussel âseason of captureâ via analysis of stable oxygen isotope ratios in specimens recovered from two Late Woodland sites located along the Yazoo River, Mississippi. As freshwater mussel shells are composed of aragonite, a metastable form of calcium carbonate (CaCO3), they can suffer greatly from the impact of meteoric diagenesis. Because of this, samples must be evaluated for diagenesis prior to any geochemical analysis taking place. Archaeological shell samples were examined via thin-section petrography and scanning electron microscopy (SEM). Visual analysis indicated pristine aragonite microstructure and crystallography in all archaeological shell samples, and confirmed their suitability for isotope analysis. Vetted shells were then micromilled across accretionary growth bands, and analyzed for their oxygen isotope signatures. Isotope profiles were then interpreted for their individual âseason of captureâ, and oscillation patterns for 22 shell specimens indicated mussels were being collected in all four seasons. These data support the view that at least some portion of the human population at both sites engaged in shellfishing activities year-round, indicating sedentary populations at both locales. The shell assemblages were also investigated for the purpose of informing modern conservation efforts (i.e., âapplied zooarchaeologyâ). Nearly 24,000 valves were analyzed taxonomically, yielding the presence of 37 species, of which 24 represented new river records for the Yazoo River. These data provide a valuable historical perspective, cataloging communities as they existed prior to extensive modern impacts, thus representing an ecological baseline to be compared with modern populations. Though modern data are extremely limited for the river, the study revealed it once supported a diverse mussel community containing numerous species currently considered rare, endangered, or extinct in Mississippi
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Enhancing adolescent development : the development of the Maple Valley School program and a theory for psychoeducational practice.
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Smugglers and state-builders : opiate trafficking and institutional development in interwar Egypt and Turkey
During the late 1920s and early 1930s, Turkey and Egypt constituted the worldâs largest producer and consumer of opiates respectively. Throughout this period, tons of heroin and morphine flowed across the Eastern Mediterranean, triggering an unprecedented epidemic that swept through Egypt and claimed nearly four percent of the countryâs population as addicts. However, the immense impact of the interwar opiate trade and epidemic on the societies, economies, and institutions of interwar Turkey and Egypt remains largely absent from Middle Eastern historiography.
Drawing on Egyptian and Turkish state records, memoirs, and periodicals, this research incorporates the complex networks of opiate traffickers, distributors, consumers, law enforcement agents, bureaucrats, and diplomats into the narrative of regional history. It contends that Egyptians, by participating in the opiate trade, formed profitable networks that helped relieve local economic pressures resulting from the Great Depression, which devastated the national cotton economy and, with it, the Egyptian middle class. While the interwar opiate trade generated considerable illicit economic activity, government responses to the epidemic created opportunities for local bureaucrats and politicians to overcome the stringent fiscal austerity of the semi-colonial Egyptian state, build enforcement institutions like the Central Narcotics Intelligence Bureau, and provide public health services such as drug treatment. Simultaneously, Egyptian journalists and diplomats responded to the epidemic by contributing to a growing tide of international diplomatic, economic, and popular pressure that prevailed upon Turkey to introduce narcotics regulation in the early 1930s. Turkeyâs subsequent move to regulate the opiate industry by creating the Narcotic Substances Monopoly transformed this illicit trade into a major source of government revenue that fueled an emerging program of statist development.Middle Eastern Studie
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