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981.
AbstractThe current system of federal advisory committees in the United States is both extensive and expanding. While there are significant differences between specific advisory bodies regarding their constitution, construction, and role in the process of public policy-making, the system itself facilitates the permanent institutionalization of linkages and dependencies between interest associations and federal administrative agencies. Indeed, it moves the role of pressure group influence on the policy-making process from that of a suspect input to that of a welcome withinput. Utilizing data derived from advisory committee compliance with the 1972 Federal Advisory Committee Act and selected case study material this article begins the process of exploring how the system functions, who participates in it, what impact it has on the development and formation of public policy, and who are its ultimate beneficiaries. It concludes by developing a framework for the assessment of potential advisory committee power and influence on the process of administrative policy-making and advances a preliminary assessment of the domination of industry interests on departmental advisory committees. 相似文献
982.
David K. Thulman 《Southeastern Archaeology》2013,32(3):171-192
ABSTRACTSince a radiocarbon chronology of the Dalton culture in the Southeast was first proposed, several new sites have been dated. I propose a new chronology based on radiocarbon dates from sites in the Dalton Heartland and its eastern periphery using Bayesian statistical models in OxCal and an analysis of the associated diagnostic projectile points. The analyses indicate that the Dalton culture probably evolved from the Clovis or Gainey phenomena about 12,680?cal?BP (ca. 10,700?BP) and lasted at least until ca. 10,400?cal?BP (ca. 9,200?BP), if not several centuries later. I propose early and late Dalton phases that follow changes in how Dalton points were made and resharpened. It appears that the people living to the east of the Heartland followed a different trajectory of projectile point evolution. There, notched points appear about 11,500?cal?BP, while in the Heartland, true notched points do not appear in large numbers until the Graham Cave point over 2,000 years later. The chronologies demonstrate that early, coeval, region-wide cultural changes may not have been the norm. They also raise interesting questions about how people in the Heartland and its eastern periphery interacted. 相似文献
983.
Michael K. Steinberg 《Journal of Cultural Geography》2013,30(1):91-105
This paper discusses how Protestant missionaries have affected the core cultural ecological activities among the Mopan Maya, specifically focusing on the maintenance of maize diversity and stingless beekeeping. Although seemingly unrelated to activities such as maize farming and beekeeping, foreign Protestant missionaries disrupt the traditional relationship with and perception of the natural world held by the Mopan Maya. Core cultural ecological activities have declined in importance and frequency as the spiritual landscape changes. This paper will demonstrate that in the traditional Mopan Maya world, religion, environment, and land use activities are often interwoven. When change occurs in one area, the ramifications of this change are often seen in other areas of the Mopan Maya cultural ecological landscape. The Mopan interweave objects in the natural world with those in the spiritual world. 相似文献
984.
985.
986.
The spatial aspects of marriage in two Sikh villages in the Indian state of Punjab are investigated with the findings compared to earlier sudies in other parts of India. One village had experienced the Green Revolution, hut the second had not. A radius of roughly 25 miles demarcates the limit of over 80% of marriage interaction in both villages, and a “crater effect” was observed in the distance decay of marriages. An expansion of the marriage field had taken place in the village influenced by Green Revolution changes, whereas no similar change occurred in the village practicing traditional agriculture. Both the extent of the marriage field and the variations in the intensity of marriage links within the field were affected by socio-economic factors including level of education, caste and extent of land ownership. 相似文献
987.
988.
A new approach has been developed for finding optimal location of sensors in 3D multi-storeyed buildings. This approach is based on the compact probabilistic representation of acceleration response in terms of its covariance matrix. For a specified number of sensors, the optimal location has been taken to be the one for which the computed covariance matrix is closest to the exact covariance matrix of the random field constituted by the acceleration response process. It has been found that the determined sensor locations match favourably with those predicted by earlier studies for the special case of shear buildings. Further, the optimality of the determined sensor locations has also been verified by identifying the system parameters from the time series data and comparing them with those of the Finite Element Model. 相似文献
989.
Non-ductile response of structural elements, particularly columns, has been the cause of numerous documented failures during earthquakes. The objective of this experimental study was to evaluate the non-linear behaviour of non-ductile reinforced concrete short columns under lateral cyclic deformations and to evaluate rehabilitation schemes. Three reinforced concrete short columns were tested under cyclic lateral loads and constant axial load. The behaviour and effectiveness of different rehabilitation systems using carbon fibre reinforced polymers (CFRP) were investigated. Two different techniques to improve concrete confinement were used in the two rehabilitated specimens. It was found that it is possible to eliminate the non-ductile modes of failure of short column using anchored CFRP wraps. In addition, an analytical model to predict the confining effect and the total shear resistance of rectangular reinforced concrete columns with anchored fibre wraps was introduced. The confinement model is an extension to an available model for concrete confined by steel reinforcement. The model was used to predict the shear capacity of the tested specimens and has shown good results. 相似文献
990.
J. David Rogers Deniz Karadeniz Craig K. Kaibel 《Journal of Earthquake Engineering》2013,17(3):400-424
Three highway bridges spanning the Missouri River flood plain were selected for evaluation of seismic site response for moderate size earthquakes emanating from the New Madrid Seismic Zone (NMSZ) in the Midwestern United States. The NMSZ is known to be capable spawning earthquakes larger than magnitude (M) 7.0, four of which occurred in a three-month period between 1811 and 1812, and the Mw 6.0 earthquake of October 1895 centered near Charleston, Missouri. This study evaluated the likely impacts of long period motion of these historic earthquakes on three long-span highway bridges using geotechnical data obtained from recent investigations. Our results suggest site amplification between 6× and 9×, depending on the magnitude and epicentral distance. We believe that threshold magnitude for serious foundation failure and damage to these bridges is between Mw 6.5 and 6.6. Above these magnitudes widespread liquefaction is predicted, which would effect the peak horizontal acceleration and spectral accelerations, causing the ground motions to be different than predicted. Increase in amplification of the response spectra also should be expected where the periods are higher than 1.0 sec. Therefore, Mw 6.5+ earthquakes at ranges 210–260 km could be expected to engender resonant frequency problems for multiple span bridges and tall buildings (10 to 25 stories) in channel corridors containing 20 to 46 m of unconsolidated sediment. 相似文献