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961.
1997年11月8日藏北玛尼7.5级大震的预报问题 总被引:2,自引:0,他引:2
对 1997年 11月 8日的藏北玛尼大地震 ,我们曾在 1991年进行过预报 ,1997年又曾重申过这个预报。本文用我们过去提出的预报理论和方法 ,对玛尼大震的预报问题再进行更广泛的讨论。文中 ,用立交模式讨论了玛尼大震的孕育机制 ,用 35°线上的 6 0a周期讨论了该震的发生年份 ,用构造交会及“静中动判据”讨论了该地震发生的地点 ,用磁暴倍九法和引潮力增长速度讨论了该震的发震日期 ,用科里奥利力效应讨论了该震余震震级偏小的原因 ,另外 ,还讨论了有关大震 -雪灾链的问题。 相似文献
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963.
宁夏区域西夏建筑文化景观及其开发利用 总被引:4,自引:0,他引:4
蕴涵博大精深的党项族文化的西夏建筑景观表现出很高的艺术价值和独特的艺术风格,是西部难得的旅游资源。作者运用文化景观学的理论分析了宁夏区域西夏建筑文化景观,以及宁夏自然环境对西夏建筑文化景观的影响,同时指出人文社会环境与宁夏区域西夏建筑文化景观营造有更大意义。最后,作者认为宁夏区域西夏建筑文化景观的旅游开发,要在借助西夏学热,促进西夏建筑文化游的理论研究的基础上,积极展开区域协作,精心设计旅游线路,拓展旅游市场。 相似文献
964.
Self‐efficacy belief is a significant predictor of behavioral choices in terms of goal setting, the amount of effort devoted to a particular task, and actual performance. This study conceives of formation and change of self‐efficacy as a social and context‐dependent process. We hypothesized that different group factors (discretionary and ambient group stimuli) influence changes in members' self‐efficacy through differing routes (individual‐level and cross‐level processes). We tested our hypotheses using data from individuals in 169 training groups who attended a 5‐day workshop designed to increase participants' job‐search skills and efficacy. Specifically, we examined the degree of change in participants' job‐search efficacy before and after the workshop. The results showed that (a) membership diversity in education was positively related to increases in job‐search efficacy, (b) supportive leadership contributed to job‐search efficacy at the individual level of analysis with no cross‐level effects, and (c) open group climate contributed to job‐search efficacy through both individual‐level and cross‐level processes. Limitations and directions for future research are discussed. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
965.
Jin‐Yong Choi Bernard A. Engel Suresh Muthukrishnan Jon Harbor 《Journal of the American Water Resources Association》2003,39(3):623-635
ABSTRACT: To adequately manage impacts of ongoing or future land use changes in a watershed, the magnitude of their hydrologic impacts needs to be assessed. A grid based daily streamflow model was calibrated with two years of observed streamflow data, using time periods when land use data are available and verified by comparison of model predictions with observed streamflow data. Streamflow data were separated into direct runoff and baseflow to estimate the impacts of urbanization on each hydrologic component. Analysis of the ratio between direct runoff and total runoff from 30 years of simulation results and the change in these ratios with urbanization shows that estimated annual direct runoff increased from 49.2 percent (1973) to 63.1 percent (1984) and 65.0 percent (1991), indicating the effects of urbanization are greater on direct runoff than on total runoff. The direct runoff ratio also varies with annual rainfall, with dry year ratios larger than those for wet years. This suggests that the impact of urbanization on areas that are sensitive to runoff ratios, such as stream ecosystems, might be more serious during drier years than in wetter years in terms of water quality and water yield. This indicates that sustainable base‐flow is important to maintaining sound stream ecosystems. 相似文献
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968.
烟气输运和水喷淋相互作用的大涡模拟研究 总被引:2,自引:0,他引:2
本文应用大涡模拟方法,并结合Smagorinsky亚格子尺度模型,数值研究了烟气输运和水喷淋的相互作用问题。为了有效地模拟烟气输运过程,文中采用低马赫数近似下的三维可压缩Navier-Stokes方程和组分方程进行求解,并采用有限差分法数值计算了滤波后的控制方程。对于燃烧过程扣所产生的热释放,采用Lagrangian粒子携带热量的近似方法来模拟,这些运动粒子进一步用来标识烟气的输运过程,同时还近似模拟了水喷淋和热气流的相互作用过程。文中数值计算了燃烧火源所形成的热气流和烟气输运过程,以及与水喷淋的相互作用,并探讨了喷水装置的喷水量、喷射角和水颗粒直径对流动特性的影响。 相似文献
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970.
Zhang Juntao & Li Jin School of Public Administration Dongbei University of Finance Economics Dalian China 《中国人口.资源与环境(英文版)》2004,2(3)
The vulnerable eco-area is one of the important research targets in the field of sustainable development. It is the requirement of building a well-off society in an all-round way that we should study more on the vulnerable eco-areas, deal with the relationship between environmental protection and economic development, speed up the economic development in these areas and increase the living standard of the local people. This paper puts forward the countermeasures of environment---economy coordination, on the basis of the recognition of eco-environment features and social economic conditions in the vulnerable eco-areas of China, in view of the progress in sustainable development studies of the vulnerable ones, taking the transitional areas of farming and pasturing in northeast China as an example to study the regional environment vulnerability. 相似文献