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21.
DIRK KRUIJT WIM HOOGBERGEN 《Tijdschrift voor economische en sociale geografie = Journal of economic and social geography = Revue de géographie économique et humaine = Zeitschrift für ?konomische und soziale Geographie = Revista de geografía económica y social》2005,96(2):199-208
One effect of Surinam's civil war (1986–1992) has been the migration of the Maroon population and of Brazilian gold diggers to the frontier territory of the Maroni river basin. The region's new political structure is the product of a ‘partial state failure’ or a government void. In Latin America this phenomenon is generally associated with uncontrollable violence of a variety of non‐state armed actors. In our case, extreme violence is absent. The region is even the locus of a fairly peaceful multi‐ethnic social fabric, a peaceful multicultural coexistence of Maroons and Brazilian migrants, but Surinamese Maroons fled to French Guiana. In French Guiana the authorities tend to turn a blind eye to the stream of migrants, in Surinam they are more or less openly tolerated. The institutional perpetrators of the civil war violence have withdrawn from the region, alliances and treaties between the several Maroon clans and the regional indigenous village chiefs have been struck. The (informal) gold economy and the influx of Brazilian garimpeiros brings short‐term prosperity and both ethnic groups enjoy their share of the surplus, whereas transport is protected by local Maroon authorities. The Brazilian migrants have learnt to pay their informal taxes and respect the customary laws of sexual relations and marriage. 相似文献
22.
ELENA MELE 《Journal of Earthquake Engineering》2013,17(1):111-145
Welded connections, widely used in seismic moment resisting frames (MRFs) in USA, Japan and Europe, have been extensively investigated during the 1990s in order to improve their performance under severe earthquakes. In order to correctly evaluate the results of experimental research on welded connections, the differences among the American, Japanese and European current practices in designing the frame structural systems and in detailing the beam-to-column connections should be firstly appraised. In this paper, the major aspects characterising the USA, Japan and Europe design practice in moment resisting welded connections are reported, the differences are underlined and the main issues recently addressed in experimental research are reviewed. Among the several parameters which affect the connection performance, attention is focused on the effect of the beam cross-section size. Thus conclusions are drawn in terms of plastic rotation capacity as dependant on the beam size. 相似文献
23.
R. PARK∗ 《Journal of Earthquake Engineering》2013,17(2):147-174
The results of some simulated seismic load tests on reinforced concrete one-way interior and exterior beam-column joints with substandard reinforcing details typical of buildings constructed in New Zealand before the 1970s are described. The tests were conducted using both deformed and plain round longitudinal reinforcement. The interior beam-column joint cores lacked transverse reinforcement and the longitudinal bars passing through the joint core were poorly anchored. The exterior beam-column joint units contained very little transverse reinforcement in the members and in the joint core. In one exterior beam-column joint unit the beam bar hooks were not bent into the joint core. That is, the hooks at the ends of the top bars were bent up and the hooks at the ends of the bottom bars were bent down. This anchorage detail was common in many older buildings constructed before the 1970s. In the other exterior beam-column joint unit the hooks at the ends of the bars were bent into the joint core as in current practice. The improvement in performance of the joint with beam bars anchored according to current practice is demonstrated. In addition, tests were conducted on interior joints with lap splices in the beam longitudinal reinforcement bars near the column face. The tests were conducted using both deformed and plain round longitudinal reinforcement. Tests were also conducted on columns with plain round bar longitudinal reinforcement and inadequate transverse reinforcement. The reinforcing details were close to identical to those in an existing seven storey reinforced concrete building that was designed and built in New Zealand in the late 1950s. The test results give an indication of the performance of beam-column joints and members with the above now out-of-date reinforcing details. The test results reported are a summary of results reported in a number of publications written since 1994. 相似文献
24.
李续宾败亡三河之役的深层原因,不在于“抢掠与放纵”而“严重地削弱了湘军战斗力”,而主要体现在这四个方面：一是天京事变后太平天国新的领导核心的确立,太平军战斗力由此增强;二是李续宾湘军战线拉得过长,兵力分散,很难发挥集中优势兵力敢打敢拼、攻坚克强的特长;三是湖广总督官文配合不力,赵克彰等部湘军临阵脱逃,致使李续宾部湘军陷入孤军作战的绝境;四是李续宾求胜心切,意气用事,听不进他人建议,未能及时采取战略转移的措施。 相似文献
25.
皇城台护墙是石峁皇城台的重要组成部分,也是保证皇城台安全的关键,目前护墙灰缝材料风化严重且存在一定外倾变形,急需对其稳定性进行评估。通过理论推导得出了适合皇城台护墙稳定性计算公式,通过室内试验验证了公式的准确性,分析了高宽比、灰缝强度和竖向外荷载对护墙稳定性的影响。研究结果表明：护墙为内部松散的重力式挡墙,存在沿内部灰缝滑移和倾覆两种破坏类型,倾覆破坏时的倾覆角度和墙体高度、灰缝强度等多种因素相关;护墙灰缝强度相同时,在护墙底部稳定性系数最小,最易发生倾覆破坏;护墙稳定性随着高宽比及竖向外荷载增加、灰缝强度减小而降低。研究结果为石峁皇城台护墙的稳定性评估和加固提供科学依据。 相似文献
26.
近年来阿房宫考古发掘表明,秦始皇与秦二世在位时兴建的阿房宫是没有建成的“半拉子”工程,而且阿房宫遗址中未发现火烧的遗迹,这与《史记》中“阿房宫未成”的记载是相一致的,即阿房宫没有建成。秦代两度修建阿房宫之所以未成,其原因主要是由于工程规模庞大,所需的土、木、石建筑材料需要大批人力去采集、运输和加工,加之施工人力不足、修建工期短,导致秦代两度修建阿房宫均以“未成”而告终。 相似文献
27.
Anita Gulczyńska 《Children's Geographies》2019,17(4):413-426
ABSTRACTThe paper contributes to ‘geographies of education’ (Holloway, S., and H. Jöns. 2012. “Geographies of Education and Learning.” Transactions of the Institute of British Geographers 37 (4): 482–488), as it presents the typical school careers of students stigmatized in educational institutions because of their disadvantaged neighbourhoods. Drawing on qualitative research with male residents of one disadvantaged neighbourhood in ?ód? (Poland), I identify their typical careers as ‘doomed-to-fail school careers’. The paper has three aims. First, it highlights the significance of stigma-based spatially embedded school practices on the educational failure and low-paid employment of students from disadvantaged neighbourhoods. Second, it uncovers forms of school control over stigmatized students and the students’ resistance to these. Finally, I argue that Erving Goffman’s theory of stigma in human geography (Goffman, E. 1963. Stigma. Notes on Management of Spoiled Identity. Englewood Cliff, NJ: Prentice Hall) offers a unique language to describe and explain the spatially embedded educational experiences of marginalized students. 相似文献
28.
永历王朝在明清易代之际播迁于粤、桂、湘、黔、滇和缅甸等地,期间与农民军余部进行合作,建立抗清统一战线,但是在坚持了15年之后终告失败,本文试着从其内政的腐败以及与农民军合作的困难重重探寻失败的缘由。 相似文献
29.
传统观点认为刘备夷陵之战失败,原因在于"备不知兵"。本文认为,夷陵之败,并非"备不知兵",而是有其客观原因和主观原因。客观原因为刘备兵力本不占优势,加之手下缺乏得力将才,后勤供应困难,以及水军力量薄弱。主观原因则为,刘备未做好充分准备,贸然出兵;初期的军事胜利,使其产生了骄傲轻敌情绪;对形势认识不足,缺乏战略考量,卒为敌所乘。 相似文献
30.
近年来,随着语际语用学（interlanguage pragmatics）的兴起,语言迁移问题备受人们的关注,其中母语的负迁移更是跨文化和二语习得领域内学者们关注的一个重点问题,本文拟从语用迁移中的语用语言迁移和社交语用迁移的两个层面,以跨文化交际中的实例来探讨母语语用负迁移对跨文化交际中的语用失误的影响作用。 相似文献