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61.
The goal of this article is to understand the multidisciplinary field of public affairs. Based on data and text mining on the profiles and publications of all faculty members from a list of research‐oriented U.S. public affairs programs, we describe the landscape of public affairs schools and scholars, identify 15 topics in public affairs research and discuss their trends of change between 1986 and 2015, and show the clustering and hiring networks of public affairs schools. Our results suggest a broader approach to understanding the field of public affairs than the public administration focus in the literature. Although public administration is highly visible in the field, which is evidenced by the journals most favored by public affair scholars, various specific policy areas (such as health, social, urban, environmental, global, and education policies) show strong representations based on our topical analysis of public affairs research. 相似文献
62.
The Preservation and Identification of Piñon Resins by GC‐MS in Pottery from the Western Great Basin
J. Eerkens 《Archaeometry》2002,44(1):95-105
Gas chromatography — mass spectrometry analysis of a sherd from the Nevada Test Site revealed a high quantity of terpenes, including sesquiterpenoids and diterpenoids, demonstrating that piñon resins were prepared in the pot in prehistoric times. The presence of these biomarkers allowed for a very specific identification of the products prepared in the pot, a level of detail not often achieved in lipid residue analysis. That the terpenes are relatively unoxidized demonstrates that they are quite stable over long periods of time. The study also shows that sherds on the surface of archaeological sites can preserve lipids and terpenes and are amenable to organic residue analysis. 相似文献
63.
Urban evolution in the USA 总被引:17,自引:0,他引:17
On a sustained basis, cities are of non-uniform relative sizes.This paper addresses three basic issues which arise from thissimple observation by examining the size distribution of UScities over the period 19001990. First, we explore thereasons why there is a wide distribution of city sizes. Second,we characterize the evolution of the size distribution of cities,documenting growth in sizes and numbers of cities. We ask whetherthe relative size distribution of cities has remained stableover time, or if it has displayed, instead, a tendency to collapse,flatten, or otherwise change its shape. We also examine evidenceon whether the size distribution obeys Zipf's Law. Third, weexamine the degree and determinants of mobility of individualcities within this distribution, asking to what extent citiesare moving up and down in the distribution and how this movementis influenced by cities' geographic characteristics. We usea newly constructed data with consistent metropolitan area definitionsover this century, discussing the issues and linking our resultsto the relevant literature. 相似文献
64.
An important record of ground motion from a M6.4 earthquake occurring on May 1, 2003, at epicentral and fault distances of about 12 and 9 km, respectively, was obtained at a station near the city of Bingöl, Turkey. The maximum peak ground values of 0.55 g and 36 cm/s are among the largest ground-motion amplitudes recorded in Turkey. From simulations and comparisons with ground motions from other earthquakes of comparable magnitude, we conclude that the ground motion over a range of frequencies is unusually high. Site response may be responsible for the elevated ground motion, as suggested from analysis of numerous aftershock recordings from the same station. The mainshock motions have some interesting seismological features, including ramps between the P-and S-wave that are probably due to near- and intermediate-field elastic motions and strong polarisation oriented at about 39 degrees to the fault (and therefore not in the fault-normal direction). Simulations of motions from an extended rupture explain these features. The N10E component shows a high-amplitude spectral acceleration at a period of 0.15 seconds resulting in a site specific design spectrum that significantly overestimates the actual strength and displacement demands of the record. The pulse signal in the N10E component affects the inelastic spectral displacement and increases the inelastic displacement demand with respect to elastic demand for very long periods. 相似文献
65.
湖北省文物考古研究所 《江汉考古》2008,(3)
赤壁古家岭东吴墓位于赤壁市赤壁镇芦林畈村三组,当地村民在兴建住房时发现。该墓规模较大,级别较高,墓室形制结构保存比较完整,虽经两次遭受盗掘,但出土陶器仍较丰富,是研究三国东吴时期考古学文化的重要资料。 相似文献
66.
为研究南澳I号明代船体木材的保存状况,选择对其部分木材S6隔舱板和尾舱板进行树种鉴定、含水率分析,并采用现代科学的分析手段对样品进行了形貌及化学组成等分析。研究表明:南澳I号S6隔舱板和尾舱板均为山茶科的荷木;目前其平均含水率为327.78%,而正常荷木的最大含水率只有68.26%;与正常木材的化学组分相比,综纤维素降低显著,而灰分、1%NaOH抽出物含量等都有一定程度提高;木材中溶出大量可溶盐,主要以Na+、K+、Mg2+、Ca2+、Cl-、SO2-4等离子为主,总体来看各类离子的含量较高,其中,SO2-4含量最高。且含有较多硫铁化合物,主要成分为黄铁矿。总体分析表明,在海水中长期浸泡后,南澳I号木材中的纤维素等有机支撑体已经发生了严重降解,水和大量盐分充盈在细胞腔内,木船构件样品的基本密度显著降低。所以除了水浸泡除去可溶性盐之外,还要选择恰当的化学吸附剂对南澳I号木材进行脱硫工作。 相似文献
67.
YAN Huifa 《Frontiers of History in China》2022,17(3):481
The use of ding-tripod in Chu tombs was well established in the Warring States period and in most cases, it was strictly implemented. However, exceptions do exist. For example, in tomb of Marquis Yi of the Zeng state, archaeologists found two qiao-ding, which consists of two ding- tripods, one with a fitted lid and the other with a hooped lid. In the tomb No. 1 at Jiuliandun, a ding-tripod with a hooped lid was intentionally used and served as xu-ding. This paper attempts to understand burial rituals of the Chu state during the Warring State period by examining the tomb inventories (catalogues of funerary goods in the tombs) unearthed from the tomb No. 2 at Baoshan. It proposes that the use of ding-tripod in tombs was often adjusted according to the burial rituals. 相似文献
68.
Alice A. Storey Daniel Quiroz Nancy Beavan Elizabeth Matisoo‐Smith 《Archaeology in Oceania》2013,48(2):101-119
In 2007, based on direct radiocarbon dates, we presented evidence that chickens were introduced to Chile before Europeans first made contact with the New World. The pre‐Columbian age of the chicken bones and their mtDNA affinities with one of two prehistoric Pacific chicken haplogroups (E) led us to conclude that Polynesia was the most likely origin for these pre‐Columbian chickens. Subsequently, the mtDNA and radiocarbon evidence provided has been applied to a range of studies and occasionally reinterpreted. This has revealed issues related to the brevity of the initial report in 2007. Here, we provide a full discussion of the evidence, including the relevant archaeological, historical and biological information necessary to provide the context for interpreting genetic analyses and understanding their implications for addressing archaeological questions. We include a comprehensive analysis of the isotope data within a geographical and temporally relevant dataset to verify the pre‐Columbian age of the El Arenal chickens. In addition, we provide longer DNA sequences obtained from some of the ancient Chilean chicken remains to address objections raised by critics and to demonstrate that longer sequences do not change the observed affinities of the mtDNA sequences, nor their interpretation. In this analysis, historical information is used to critically evaluate the results of phylogenetic analyses. This comprehensive approach demonstrates that the examination of modern chicken DNA sequences does not contribute to our understanding of the origins of Chile's earliest chickens. Interpretations based on poorly sourced and documented modern chicken populations, divorced from the archaeological and historical evidence, do not withstand scrutiny. Instead, this expanded account will confirm the pre‐Columbian age of the El Arenal remains and lend support to our original hypothesis that their appearance in South America is most likely due to Polynesian contact with the Americas in prehistory. 相似文献
69.
70.
《SJOT: Scandinavian Journal of the Old Testament》2012,26(2):185-202
ABSTRACTThis article asks for the possible sociological and theological background of the so-called Psalms of the Righteous in the Book of Psalms. First, I discuss Christoph Levin’s understanding of this group of psalms. Then I make a close reading of Psalm 141 as a psalm which is obsessed with the implied psalmist’s fear of urging a heterodox theology. On the background of theories of “Charter Groups” (John Porter, John Kessler) and “Carrier Groups” (J.C. Alexander) and of Mary Douglas’ “group-grid theory” I propose to place Psalm 141 as well as Psalms 1, 37, and 73 within the intellectual framework of an enclave of ṣaddiqîm in Persian period Judah (and later). 相似文献