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W. S. Han M. Lu B. J. McPherson E. H. Keating J. Moore E. Park Z. T. Watson N.‐H. Jung 《Geofluids》2013,13(3):283-297
Geologic carbon capture and storage (CCS) is an option for reducing CO2 emissions, but leakage to the surface is a risk factor. Natural CO2 reservoirs that erupt from abandoned oil and gas holes leak to the surface as spectacular cold geysers in the Colorado Plateau, United States. A better understanding of the mechanisms of CO2‐driven cold‐water geysers will provide valuable insight about the potential modes of leakage from engineered CCS sites. A notable example of a CO2‐driven cold‐water geyser is Crystal Geyser in central Utah. We investigated the fluid mechanics of this regularly erupting geyser by instrumenting its conduit with sensors and measuring pressure and temperature every 20 sec over a period of 17 days. Analyses of these measurements suggest that the timescale of a single‐eruption cycle is composed of four successive eruption types with two recharge periods ranging from 30 to 40 h. Current eruption patterns exhibit a bimodal distribution, but these patterns evolved during past 80 years. The field observation suggests that the geyser's eruptions are regular and predictable and reflect pressure and temperature changes resulting from Joule–Thomson cooling and endothermic CO2 exsolution. The eruption interval between multiple small‐scale eruptions is a direct indicator of the subsequent large‐scale eruption. 相似文献
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Chris C. Park 《Geographical analysis》1978,10(3):211-228
The concept of allometric change, developed and widely applied in biology, is outlined, and the nature of static allometric changes in stream channel size, relative to drainage area, is considered at a variety of scales. Field observations from Devon, England, allow analysis of the allometric variations along individual channels, between tributaries within a network, and between streams within a region. Data collected from the literature allow these to be viewed in a global perspective. The analysis confirms the applicability and value of the concept of allometric change to channel form studies and suggests a tendency for streams to reach a steady-state allometric situation when channel capacity increases at the same rate as drainage area. The importance of a range of factors in affecting the nature of the allometric relationships is also assessed. 相似文献
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Metallurgical examination of brass and bronze objects from the medieval (AD 9th–13th century) site at Talgar in Kazakhstan shows that they were mostly cast from the quaternary copper–zinc–tin–lead system with some exceptions that were forged from binary copper–zinc alloys. Evidence is found that brass was produced in the cementation process and that the addition of tin and lead to the parent brass was considered beneficial in casting but was strictly avoided in forging. The mutual effect of zinc, tin and lead for better casting and the advantages of the binary copper–zinc alloys in forging seem to have been the major factors driving the establishment of this unique brass tradition in a society with probably limited access to tin. 相似文献
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Ji Hoon Park 《Tourism Geographies》2018,20(1):144-162
ABSTRACTA popular trend is for US colleges to organise short-term, self-funded trips for students to volunteer for several weeks in poverty-stricken communities in the global South. To explore the cultural implications of short-term, international volunteer projects, I undertake an ethnographic study of college students of who travel to a small village in Cameroon to improve the quality of drinking water and community health. I examine whether the volunteer tourism can serve as a unique opportunity to see beyond the African stereotypes to recognise the historical and structural context in which Africa continues to suffer. Although a trip such as this can be a disruptive event for students to critically evaluate the global privileges of Westerners, students tend to experience Cameroon through the lens of popular stereotypes about Africa and Western paternalism. The encounters with Africans in the absence of sufficient education about postcolonial Africa can affirm the stereotypes and cultural superiority formed in USA because students negotiate their actual experience in ways to confirm their perception of Africa. Therefore, seminars and workshops about the fundamental aspects about global inequality can help educate volunteers about the postcolonial context of foreign aid of Western countries for the Third World, and White privilege. 相似文献
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Yong Soo Park 《亚洲研究评论》2014,38(1):1-14
Soon after the death of Kim Jong-il on 17 December 2011, his youngest and previously least-known son, Kim Jong-un, was declared the next leader of North Korea. At least for now, it seems clear that the Kim Jong-un regime is determined to uphold the established policies and ideologies of its predecessor. The present study attempts to explain why that is the case using path-dependence theory. Obviously, the old policies and ideologies are intimately bound up with the political processes of the present regime. North Korea’s unique monolithic system, comprising the Juche ideology and the military-first policy, which was constructed during the Kim Il-sung and Kim Jong-il regimes, has exerted a comprehensive influence on the country’s political and socioeconomic development processes for decades, and it is clear that the existing policy and the institutional framework based on it wield a powerful influence on the current political processes. This greatly restricts the autonomy and the range of choices of the new incumbent, suggesting that path dependence is relevant in the case of the North Korean regime. 相似文献
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This article examines Korean American comedian Margaret Cho's attempts to represent Asian American identity as the star of two television sitcoms, All-American Girl (1994) and The Cho Show (2008). It begins with All-American Girl, showing how its contradictions around race, ethnicity and gender demonstrate the ideological boundaries of the network sitcom genre. It then looks at how the post-network ‘celebreality’ sitcom, The Cho Show, reproduces the assimilationist identity politics promulgated in All-American Girl even as it purports to critique them. The commercial failure of these shows is traced ultimately to the broader institutionalised racism and sexism of the US entertainment industry, its perpetuation of the neoliberal ideology of the American Dream and the internationalisation of that ideology by social minorities. 相似文献
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Sang Mi Park 《亚洲研究评论》2015,39(3):357-374
In the 1950s and 1960s, the modern Japanese state employed overseas cultural promotion as a way to maximise its interests and image not only in international contexts but also at home. By juxtaposing the Takarazuka Revue’s performances in the United States and Japan during the postwar period, this paper argues that the overseas promotion of this Japanese theatre troupe both depended upon and reinforced the Japanese populace’s nationalistic pride in its culture. The paper also addresses the ways in which the Japanese government used Takarazuka’s theatrical presentations as a means of pursuing its domestic and diplomatic agendas: improving Japan’s international position by proposing shared aspects of popular culture with the US and increasing its sense of nationalism by propagating cultural pride. In doing so, the paper explicates the ways in which Japanese popular cultural considerations interfaced with political concerns in the shaping of postwar Japan’s national identity. 相似文献
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B. S. Chang C. S. Uhm C. H. Park H. K. Kim H. S. Jung J. H. Ham G. Y. Lee D. H. Kim K. J. Lee I. S. Bang C. S. Oh D. H. Shin 《International Journal of Osteoarchaeology》2008,18(6):624-631
Our previous studies on the ultramicroscopic structure of mummy hair from Joseon Dynasty (1392–1910) tombs sealed with a lime‐soil mixture barrier (LSMB) have provided initial, basic information on their preservation status. Numerous additional cases of various conditions are required in order to provide data sufficient for establishing Korean mummy preservation patterns on a firm basis, however, and so we performed electron microscopic studies on hair taken from a full‐term, intrauterine baby mummy found in Paju, Korea. The baby mummy was found within the uterus of a 16th‐century mummified woman aged 20–30 years old. Since the labour and delivery stage for this case was 2, and the uterus was found to be ruptured, the cause of death of both the mother and the baby was likely to have been hypovolemic shock occurring during labour. In scanning electron microscopic (SEM) and transmission electron microscopic (TEM) studies, we found that the surface of the hair of the baby mummy was coated with crystalline substances, mainly on the side facing the vaginal orifice. We also observed well‐preserved cuticle, cortex and medullar layers, completely preserved cuticle‐layer scales, as well as macrofibrils and melanin granules evenly spread within the cuticle and cortex layers. Because studies on infant or subadult mummies are very few, and since they have focused mainly on the palaeopathological aspects of those mummies, the preservation pattern of the hair of a full‐term baby mummy could contribute significantly to our knowledge of mummies from around the world. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献