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981.
982.
Jinge Wang Aijun Su Wei Xiang Hsin-Fu Yeh Chengren Xiong Zongxing Zou Cheng Zhong Qingbing Liu 《Landslides》2016,13(4):795-804
The original Badong County, Hubei, China, was mainly below the highest water level of the Three Gorges Reservoir, which is 175 m above sea level. The new downtown of Badong was rebuilt in the Huangtupo area between 1982 and 1991. After detailed geological investigation in the Huangtupo area, four independent landslides were identified, making it one of the largest and most harmful landslide group in the Three Gorges Reservoir area. Since 2003, abundant data have been obtained from the Huangtupo No. 1 sliding mass about rainfall, water level, earth surface deformation and deep deformation. The monitoring data indicate that the earth surface and deep deformation of this landslide is closely related to the seasonal rainfall and water level fluctuation of the reservoir. During increases in the water level, the earth surface deformation velocity decreases, and then increases obviously in the subsequent water level decreasing stage. Because the water level drawdown period overlaps with the rainy season in this area, the earth surface deformation is affected by both rainfall and water level. The deformation velocity of the earth surface caused by rainfall is about 5 mm/month, while that caused by water level decrease is 5–7 mm/month. On the contrary, the deformation velocity of the deep sliding mass accelerates 2 to 3 times faster than average during water level increase. The distinction of surface and deep deformation regulations indicates that the effects of seasonal rainfall and water level fluctuation on the stability of reservoir wading landslides are different. Based on all monitoring data, we also found that the Huangtupo No. 1 riverside sliding mass is creeping seasonally during the seasonal rainfall and periodic reservoir water level fluctuation. The deformation velocities of the east regions of the sliding body indicate acceleration, making these regions even more dangerous. 相似文献
983.
E.?Spisni S.?Seo S.?H.?JooEmail author C.?Su 《International Journal of Environmental Science and Technology》2016,13(10):2485-2494
Many consumer products containing ZnO have raised concern for safety in regard to environmental impact and the public health. Widely used sunscreens for protecting against UV and avoiding sunburns represent a great exposure to nano-ZnO, one of the ingredients commonly applied in sunscreens. Applying nanoproducts on beaches may release nanoparticles unintentionally into the ocean. Despite the accumulation of such nanoproducts in the ocean harming or being detrimental to critical marine organisms, few studies have investigated the release and potential toxicity of nanoparticles extracted from products and compared them with those from industrial-type nanoparticles. Results show that the cytotoxicity of both industrial- and sunscreen-derived nano-ZnO to the marine diatom algae, Thalassiosira pseudonana, increased as exposure increases over time, as measured by growth inhibition (%) of the algae at a constant concentration of nano-ZnO (10 mg/L). The extent of toxicity appeared to be higher from industrial-type nano-ZnO compared with sunscreen-extracted nano-ZnO, though the extent becomes similar when concentrations increase to 50 mg/L. On the other hand, at a fixed exposure time of 48 h, the cytotoxicity increases as concentrations increase with the higher toxicity shown from the industrial-type compared with sunscreen-induced nano-ZnO. Results indicate that while industrial-type nano-ZnO shows higher toxicity than sunscreen-derived nano-ZnO, the release and extent of toxicity from nano-ZnO extracted from sunscreen are not trivial and should be monitored for the development of safe manufacturing of nanomaterials-induced products. 相似文献
984.
Cheng Su Cunjun Feng Xizhi Wang Zhicai Huang Xiaocan Zhang 《Earth Science Informatics》2016,9(2):225-233
Flat surfaces or areas with no local gradient are general types of terrain in raster Digital Elevation Models (DEMs). When a DEM is used for automated hydrological analysis, it is necessary to assign flow directions over flat surfaces. This paper presents an improved algorithm for assigning flow directions over flat surfaces that builds on earlier work and offers efficiency improvements. The improved algorithm use distance transform method to calculate the distance values of cells in flat surfaces towards lower terrain and away from higher terrain, which can replace the recursive process in the earlier algorithm by a linear process, and reduce random data access. Furthermore, the improved algorithm assigns weights with different values and signs to the two distance values to guarantee that all flat surfaces are drained, which avoids the need to label each flat surface using the flood-fill algorithm in the earlier work. Comparisons of speed indicate that the improved algorithm is more efficient in assigning flow directions over flat surfaces. 相似文献
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987.
Culture provides an important perspective to understand society. It is one of the key factors that impact how people behave themselves, interact with one another, view the world; what they believe and value. Therefore, a good understanding of public disaster awareness and disaster coping is impossible without taking their culture context into consideration. Since the 1960s, cultural dimension in disaster issues and/or disaster reduction practices has been attracting increasingly attention; many empirical or theoretical explorations have been reported. This review aims to give an overview of research progresses on how culture impacts public awareness and coping of disasters, and analyze the corresponding implications for disaster research and disaster reduction practice. This review summarizes that: ①There is unanimous consensus on public awareness and coping of disaster, which are affected by their culture context. While the knowledge about the ways and degree of impact is still limited, further research is warranted. In addition, more systematic and in-depth studies conducted from cross-cultural perspectives are needed to design to further explore the origins of variance in public disaster awareness and coping, and to what extent from cultural differences. ②Research on public awareness of disaster, emergency response and recovery indicated that culture might have double-side impacts on disaster management—sometimes cultural factors such as value, norm, custom and belief might lead to people more vulnerable than the others, even could be the root causes, but they could also be the source of people’s resilience to disaster in some cases. How to identify those positive and negative impacts, then develop cultural-oriented disaster management policy is a challenge issue, which need special attention. ③There is an increasing acknowledgement that local knowledge and disaster subculture could play an important role in public disaster coping, while the lacking of the awareness of the value of local knowledge, the change of lifestyle, and the impact from external culture pose a threat to the inheritance of some local, traditional disaster coping strategies. So exploring how to conserve, protect, identify, document them, then combine them with modern science and technology should and will be the focus of relevant studies. On the bases of these summarizations, in terms of cultural dimension of natural disaster research in China, systematic and in-depth studies are needed to explore how Chinese culture affects public disaster awareness and coping, what cultural resources can be used in disaster (risk) reduction and for building and enhancing disaster resilience, and how to use them. 相似文献
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990.
Slope-confined submarine canyons in the Baiyun deep-water area,northern South China Sea: variation in their modern morphology 总被引:1,自引:0,他引:1
X. S. Li Q. J. Zhou T. Y. Su L. J. Liu S. Gao S. W. Zhou 《Marine Geophysical Researches》2016,37(2):95-112
On the basis of newly collected multibeam bathymetric data, chirp profiles and existing seismic data, we presented a detailed morphological interpretation of a series of slope-confined canyons in water depths of 300–2000 m in the Baiyun deep-water area, northern margin of the South China Sea. Although these canyons are commonly characterized by regular spacing and a straight-line shape, they vary in their lengths, starting and ending water depths, canyon relief, slope gradients, wall slope gradients and depth profiles along the axis. The eastern canyons (C1–C8) have complex surface features, low values in their slope gradient, canyon relief and wall slope gradient and high values in their length and starting and ending depth contrasting to the western ones (C9–C17). From the bathymetric data and chirp profiles, we interpret two main processes that have controlled the morphology and evolution of the canyons: axial incision and landsliding. The western part of the shelf margin where there were at least four stages of submerged reefs differs from the eastern part of the shelf margin where sedimentary undulations occurred at a water depth of ~650 m. We consider that the variation in morphology of submarine canyons in the study area is the result of multiple causes, with the leading cause being the difference in stability of the upper slope which is related to the submerged reefs and sedimentary undulations. 相似文献