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11.
王波  雷雅钦  张琪 《人文地理》2022,37(1):164-170
本研究收集2000、2010、2018年环南海区域各国家/地区间国际机场的跨境客运、货运航线和航班数目,探究近20年该区域跨境航空客运和货运网络的整体结构与空间格局演化特征,并综合客运和货运网络分析枢纽机场体系演化。研究发现:①该区域跨境航空网络的整体结构具有覆盖范围扩大、“小世界”效应明显和“无标度”特征显著的特点,但客、货运网络的演化存在差异。②该区域跨境航空客运网络具有明显的轴—辐组织结构特征,并呈现“多核心化”的演化趋势,而货运网络中以香港、新加坡为枢纽的轴—辐组织结构与局部性的“点—点”航空货运联系并存,尚未形成全局性的轴—辐组织结构。③该区域的区域客、货运枢纽机场发展呈现综合化、专业化趋势,香港(HKG)和新加坡(SIN)长期以来保持优势地位。  相似文献   
12.
The Impact of Energy,Transport, and Trade on Air Pollution in China   总被引:1,自引:0,他引:1  
A team of U.S.- and China-based geographers examines the relationship between China's economic development and its environment by modeling the effects of energy, transport, and trade on local air pollution emissions (sulfur dioxide and soot particulates) using the Environmental Kuznets model. Specifically, the latter model is investigated using spatial econometrics that take into account potential regional spillover effects from high-polluting neighbors. The analysis finds an inverted-U relationship for sulfur dioxide but a U-shaped curve for soot particulates. This suggests that soot particulates such as black carbon may pose a more serious environmental problem in China than sulfur dioxide. Journal of Economic Literature, Classification Numbers: C50, F10, Q43, R40. 4 figures, 3 tables, 47 references.  相似文献   
13.
龙庆  任瑞俊  谭旭菲  韩明  薛延涛 《神州》2012,(26):48-49
随着人们生活水平的不断提高,对于家中装饰品的选择也更为美观化、健康化。但由于装修等原因,目前室内环境的有害物质达数千种之多。另外,电器使用的增多,使室内的负氧离子数量降低,而摆放绿色植物不仅可以美化环境,还可净化空气,排除居室有害物质。随着人们对环境美观和身心健康更加深刻的理解和认识,绿色植物,自然成为大众对于家庭装饰中最为青睐的"产品"。在提倡创建和谐社会的今天,将观赏植物应用于室内设计也是一种需要,一种时尚,同时也解析了未来室内装饰的发展方向。  相似文献   
14.
Late Pleistocene Ice Age Crocuta crocuta spelaea ( Goldfuss, 1823) hyenas from the open-air gypsum karst site Westeregeln (Saxony-Anhalt, central Germany) is dated into the early to middle Late Pleistocene. Hyena clans apparently used the karst for food storage and as “commuting den”, where typical high amounts (15% of the NISP) of hyena remains appear, also faecal pellets in concentrations for den marking purposes. Additionally small carnivores Meles, Vulpes and Mustela appear to have used some cavities as dens. Several hundreds of lowland “mammoth steppe fauna” bones (NISP = 572) must have been accumulated primarily by hyenas, and not by Neanderthals at the contemporary hyena/human camp site. Abundant caballoid horse remains of “E. germanicus Nehring, (1884)” are revised by the holotype and original material to the small E. c. przewalskii horse. Woolly rhinoceros Coelodonta antiquitatis remains are also abundant, and were left in several cases with typical hyena scavenging damages. Rangifer tarandus (11%) is mainly represented by numerous fragments of shed female antlers that were apparently gathered by humans, and antler bases from male animals that were collected and chewed in few cases (only large male antlers) by hyenas. The large quantities of small reindeer antlers must have been the result of collection by humans; their stratigraphic context is unclear but such large quantities most probably resulted from schamanic activities. The hyena site overlaps with a Middle Palaeolithic Neanderthal camp, as well as possibly with a later human Magdalénian site.  相似文献   
15.
Two American geographers comment on the preceding analysis of restructuring of Beijing's social space (Feng et al., 2007) by presenting observations on the city's Olympic Games, forthcoming in the summer of 2008. The authors focus on some of the more salient geographical impacts stemming from construction, relocation, and related measures undertaken by the authorities to accommodate the event. Included in the paper are sections on environmental concerns (particularly air pollution), infrastructure (water supply, automobile traffic, and mass transit), and relocation and displacement of residents (particularly of migrants and other disadvantaged segments of the population). Journal of Economic Literature, Classification Numbers: I31, O15, O18, P20. 2 figures, 2 tables, 44 references.  相似文献   
16.
This Article investigates the assertion by many Indian agronomists that methods of water management advocated by various Research Institutes are not being applied in the field. The sample village studies on the coastal plain around Madras and in the Cumbum Valley to the West of Madurai were carried out in 1969. Particular reference is also made to the Coimbatore Agricultural Research Centre in Tamilnad and the value of informed leadership in the villages of South India. “Although India can boast of her gigantic feats in the storage of water for irrigation and the distribution thereof in well planned channel systems, her performance in the actual application within the field continues to be outdated”. — (A. P. Bhattacharya1).  相似文献   
17.
MARTIN KITCHEN. A World in Flames: A Short History of the Second World War in Europe and Asia, 1939–1945. London and New York: Longman, 1990. Pp. xii, 377. $24.95 (CAN);

R.A.C. PARKER. Struggle for Survival: The History of the Second World War. Oxford: Oxford University Press, 1990. Pp. xii, 328. £5.95;

H.P. WiLLMOTT. The Great Crusade: A New Complete History of the Second World War. New York: Free Press (Macmillan), 1989. Pp. xii, 500. $24.95 (us);

JOHN KEEGAN. The Second World War. Sydney: Hutchinson, 1989. Pp. vii, 608. Aus $39.95;

JOHN ELLIS. Brute Force: Allied Strategy and Tactics in the Second World War. London: André Deutsch, 1990. Pp. xxii, 643. £19.95;

ALAN F. WILT. War from the Top: German and British Military Decision Making during World War II. Bloomington and Indianapolis: Indiana University Press, 1990. Pp. x, 390. $35.00 (us).  相似文献   
18.
A senior American specialist on China and noted geographer presents a framing commentary and analysis of three preceding papers (Yeung et al., 2008; Shen, 2008; and Tang, 2008) comprising a symposium on Hong Kong and Macao under Chinese sovereignty after Great Britain and Portugal ceased to govern these cities in the late 1990s. The paper commences with an historical overview, noting the years of colonial rule, discussing relations with Mainland China before and after its economic reforms were set in motion, and evaluating the post-handover period in light of the material and arguments in the preceding papers. Included in the paper is also a section on environmental degradation in Hong Kong. Journal of Economic Literature, Classification Numbers: N950, O18, Q30, R11. 3 figures, 17 references.  相似文献   
19.
This article examines the processes of displacement and dislocation for the aircrew that came together in 1940–42 to form the Forces aériennes françaises libres (FAFL). It uses quantitative and qualitative methodologies to examine the background and motivations of the men of the FAFL. It also seeks to utilise current understandings about the French right in examining the political impulses of Free French pilots. The article concludes with some suggestions about the long term significance on French life of the displacements and dislocations of 1940–42.  相似文献   
20.
Years ago, Bill Gormley introduced public policy scholars to a new and innovative salience- complexity typology for regulatory policies. This typology not only helps scholars catalog numerous policies into distinct categories, but also helps explain variation in political processes. Specifically, different policies provide different incentives for political actors to be involved in policymaking. Salience encourages activity on the part of elected officials; complexity often requires policymaking outside of the public sphere. In this article, I extend Gormley's salience-complexity typology to more than just regulatory policies and confirm that levels of institutional activity vary across this range of public policies. I also expand on Gormley's contribution by differentiating the distinct impacts that policy type has on the policy activities of Congress and the presidency, and propose that institutional activity differs according to the dynamics of a policy's salience.  相似文献   
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