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171.
Mussels (Mytilus galloprovincialis) were transplanted to seven stations around a large shipyard for 126 days to evaluate tributyltin (TBT) contamination. Although the application of TBT-based paints to ships is totally banned in Korea, butyltin compounds were found to accumulate in mussels following transplantation. Concentrations of TBT and total butyltins in transplanted mussels near the shipyard were in the range of 40-350 ng Sn/g and 74-530 ng Sn/g on a dry weight basis, respectively. Obviously, low TBT concentrations (6.0-53 ng Sn/gdw) were determined in mussels at four stations outside the shipyard. A negative gradient of TBT concentrations and TBT portion to total butyltin concentrations were found in both the surface water and transplanted mussels according to distance from the shipyard. In addition, TBT concentrations in surface water and transplanted mussels showed significant correlation (r(2) = 0.71; p < 0.001). These results indicate that the shipyard still releases fresh TBT into surrounding waters even after TBT regulation in Korea, and mussel transplantation is useful in evaluating TBT contamination in shipyard area.  相似文献   
172.
This paper revisits the debate on marriage migration by highlighting the role of governing power and individual response in the process of migration decision‐making and post‐settlement of Vietnamese marriage migrant activist women in South Korea. It contributes to current marriage migration debates by employing the lens of ‘governmobility’ and ‘spatial capability’. The research looks at how female migrant activists maneuver coercion, resistance, and activism, both governed by nation‐state politics, but also actively deciding their fate amidst pressures of the global marriage market. Based on in‐depth interviews with 21 Vietnamese marriage migrant women who have worked in mentoring, counselling and translating for other Vietnamese migrants, our findings demonstrate that marriage migrants are positioned in between two nation‐states whose perspectival focus is on relieving the tensions of their own domestic job and marital markets. At the same time, these women have broken free from the inertia of socio‐familial status quo and state intervention to become self‐governing agents of mobility in various stages of their migration and adaptation. Fueled on by their position as activists, the marriage migrants then expand their spatial capability to place‐making—shifting the notion of freedom from simply taking part in mobility to reshaping their locale.  相似文献   
173.
刘健  秦华峰  孔祥淮  李军 《第四纪研究》2007,27(6):1031-1039
黄东海陆架和朝鲜海峡等5个泥质沉积区全新世中期以来(自约6kaB.P.至今)的细粒沉积物主要是黄河、长江和朝鲜半岛的河流入海物质在复杂的海洋动力系统中的沉积产物。对取自山东半岛北部近岸泥质区和长江口以南的闽浙沿岸泥质区(舟山群岛近岸海区)的表层细粒沉积物(粘土质粉砂和粉砂质粘土)开展了详细的岩石磁学测试,包括磁化率、等温剩磁和样品磁化率随温度的变化等分析,并将实验数据与以往研究过的济州岛西南陆架区、南黄海东南部陆架区和朝鲜海峡西岸等3个泥质沉积区细粒沉积物的磁学特征进行比较研究。结果表明,上述5处细粒沉积物的磁性矿物主要组分为磁铁矿、磁赤铁矿和赤铁矿,其中低矫顽力磁性矿物为主,平均粒度为准单畴(PSD)。根据磁性矿物的粒度和低矫顽力组分的相对含量,这5处细粒沉积物可以划分为3种类型:第1种类型是朝鲜海峡西岸细粒沉积物,其磁性矿物的粒度最粗,低矫顽力组分的相对含量为中等;第2种类型是南黄海东南部陆架细粒沉积物,其磁性矿物的粒度为中等,低矫顽力组分的相对含量最大;第3种类型是山东半岛北部近岸、闽浙沿岸(舟山群岛近岸)和济州岛西南陆架区的细粒沉积物,其磁性矿物的粒度最细,低矫顽力组分的相对含量最低。在这5处细粒沉积物中,闽浙沿岸(舟山群岛近岸)细粒沉积物的磁性矿物含量最高,其他4处细粒沉积物的磁性矿物含量都较低且大体相当。这种磁学特征的差异反映了物源的不同。从磁学特征来分析,济州岛西南陆架区的泥质沉积物主要来自黄河和长江;南黄海东南部泥质区的主要物源是朝鲜半岛进入黄海的河流,黄河和长江对其没有重要贡献。  相似文献   
174.
丹东市赴朝边境旅游发展研究   总被引:8,自引:0,他引:8  
丹东市是中国最大的边境城市,赴朝旅游是丹东市特许经营的旅游项目,赴朝旅游是丹东市特许经营的旅游项目,赴朝旅游是其旅游业发展的龙头,赴朝旅游主要受制于朝鲜半凫局势的走向,其发展趋势是不断增长的,并且市场具有较大的不稳定性。赴朝旅游带动丹东市旅游业全面发展的同时,也为朝鲜经济的全面振兴注入了活力。  相似文献   
175.
Outdoor light at night (LAN) would be a public concern potentially associated with adverse health outcomes mainly in developed countries, but it might also be an environmental health issue in developing countries. However, there have been few studies reporting the spatial and temporal aspects of LAN level changes incorporated with population exposure in such nations. Therefore, we analyzed the spatiotemporal patterns of outdoor LAN exposure changes across the Republic of Korea (ROK), a developing country in Asia, between 1995 and 2010. In addition, we incorporated the population and its demographic characteristics of light exposure in this research. We utilized Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) observations as a spatial proxy of LAN and the ROK census data. This research observed 57.6% (≈57,800 km2) of land areas in the country to experience increases in outdoor artificial illumination at nights. The highest levels of LAN were found to affect about 58% of the total ROK population with major impacts on young and middle-aged people in recent years. Taking this research into account, it would require taking appropriate measures in controlling and abating outdoor artificial lights at night for both developing and developed countries. We anticipate that those efforts could prevent adverse health outcomes, for example, female breast cancer, potentially associated with LAN exposure.  相似文献   
176.
In the Jungwon area, South Korea, two contrasting types of deep thermal groundwater (around 20–33 °C) occur together in granite. Compared to shallow groundwater and surface water, thermal groundwaters have significantly lower δ18O and δD values (> 1‰ lower in δ18O) and negligible tritium content (mostly < 2 TU), suggesting a relatively high age of these waters (at least pre-thermonuclear period) and relatively long subsurface circulation. However, the hydrochemical evolution yielded two distinct water types. CO2-rich water (PCO2 = 0.1 to 2 atm) is characterized by lower pH (5.7–6.4) and higher TDS content (up to 3300 mg/L), whereas alkaline water (PCO2 = 10− 4.1–10− 4.6 atm) has higher pH (9.1–9.5) and lower TDS (< 254 mg/L). Carbon isotope data indicate that the CO2-rich water is influenced by a local supply of deep CO2 (potentially, magmatic), which enhanced dissolution of silicate minerals in surrounding rocks and resulted in elevated concentrations of Ca2+, Na+, Mg2+, K+, HCO3 and silica under lower pH conditions. In contrast, the evolution of the alkaline water was characterized by a lesser degree of water–rock (granite) interaction under the negligible inflow of CO2. The application of chemical thermometers indicates that the alkaline water represents partially equilibrated waters coming from a geothermal reservoir with a temperature of about 40 °C, while the immature characteristics of the CO2-rich water resulted from the input of CO2 in Na–HCO3 waters and subsequent rock leaching.  相似文献   
177.
Kosuke  Egawa  Yong Il  Lee 《Island Arc》2008,17(1):109-128
Abstract   Thermal maturity of the Upper Triassic to Lower Jurassic Nampo Group, a sediment-fill of the Chungnam Basin located in the central western part of South Korea, was assessed by illite crystallinity measurement and sandstone microtexture analysis. The Nampo Group consists of a fluvio-lacustrine deposit bearing meta-anthracitic coals and was over-thrusted by the basement rocks. Sandstones are characterized by down sequence increasing illite crystallinity, from anchizone to epizone, which is strongly suggestive of burial heating. Deep-burial diagenesis and deformation are evidenced by well-developed pressure solution textures, whose intensity tends to increase down sequence, and by ductile deformation in the lowermost strata. On the basis of the result of illite crystallinity measurement, the maximum paleo-temperature and total burial depth of the Nampo Group are estimated to be ca 340°C and 10 km, respectively; these conditions are in good agreement with the observed ductile deformation features. The absence of strata younger than the Nampo Group in and around the Chungnam Basin suggests that deep burial of the Nampo Group was caused by tectonic crustal loading. The tectonic overload was because of basement over-thrusting that occurred during the Jurassic Daebo orogeny, which is closely related to the orthogonal subduction of the Izanagi Plate beneath the East Asian continent. Subsequent hydrothermal alteration disturbed the thermal maturity pattern, resulting in anomalously high illite crystallinity and meta-anthracitization.  相似文献   
178.
韩国电子政务建设对我国的启示   总被引:1,自引:0,他引:1  
韩国电子政务起步于20世纪80年代左右,他们在电子政务建设上取得的成绩、有益经验和其建设过程,对加速我国今后电子政务建设具有较好的借鉴意义。  相似文献   
179.
Recent investigation suggests that volume transport through the Tsushima/Korea Strait often has double peaks during the summer to autumn period with decreasing transport in September. The satellite-observed wind changes from weak northwestward (across-strait) in summer to strong southwestward (along-strait) in early autumn (September) in the strait. Such a strong along-strait wind is related to tropical cyclones, which frequently pass through the East China Sea in September. The effect of the along-strait wind component on the transport variation is examined using a three-dimensional numerical model. The simulated volume transport through the Tsushima/Korea Strait shows realistic seasonal and intra-seasonal variations. According to sensitivity experiments on local winds, the transport variations in September are mainly generated by strong along-strait (southwestward) wind rather than weak across-strait wind. The strait transport responds to the along-strait wind (southeastward), which produces a sea level increase along the Korean coast, resulting in the geostrophic balance across the strait. The transport minimum through the Tsushima/Korea Strait in September can be determined by the combination of the across-strait geostrophic and along-strait ageostrophic balances. The Editor-in-Chief does not recommend the usage of the term “Japan/East Sea” in place of “Sea of Japan”.  相似文献   
180.
The study of life course has become a central feature of geographical and other social science approaches to youth and migration. It has offered scholars possibilities to explore the timing of events, experiences of time and in the context of migration, the opportunity to analyse mobility patterns in relation to life stages and transitions. Yet, despite this emphasis, much life-course research rests on a limited understanding of time characterised as a linear or even static entity that regulates life in a way that occludes the complex directionality and rhythms of time. In this paper we seek to push beyond these limitations of life course research by developing broader theoretical understandings of time in migration. In particular, we develop a Heideggerian analysis of the migration stories of western English teachers in South Korea, an example of migration as part of a youth–adult transition. Our analysis reveals that the mobilities of English teachers need to be understood in much more complex and relational ways and we draw attention to their more-than-subjective temporalities, questions of attunement to being (affect) and temporal openness in migration. Through this discussion the paper highlights three key areas for further development of scholarly understandings of time in migration: the situatedness of migrants, the holistic character of migration as a happening in the world, and the eventfulness of migration, always characterised by an openness of possibility for emergent spatio-temporal differentiation.  相似文献   
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