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排序方式: 共有2735条查询结果,搜索用时 359 毫秒
171.
R. Saravanathamizhan N. Mohan N. Balasubramanian V. Ramamurthi C. Ahmed Basha 《洁净——土壤、空气、水》2007,35(4):355-361
In the present investigation, treatment of textile effluent using an electrochemical technique was designed and analyzed using the Box-Behnken method. The influence of individual parameters on electro-oxidation of textile effluent has been critically examined using the response surface method (RSM), and a quadratic model for chemical oxygen demand (COD) reduction has been developed. It has been observed from the present analysis that the predicted values are in good agreement with experimental data with a correlation coefficient of 0.945. 相似文献
172.
东天山秋黄韧性剪切带位于新疆东部两大板块碰撞接合地带,东西延长逾600km,由石炭系组成,规模巨大,分带明显,宏微观变形标志清晰,石英C轴组构呈点极密型,分为四期变形,序列演化明显,应变测量属平面单剪,剪切位移量达75km以上,存在脆韧性变形转换,变形时代为海西中晚期,强弱应变相间排列的标度不变性特征明显,变形机制属地壳中深层次塑性流变和韧性剪切,与板块间的俯冲碰撞构造演化密切相关。控制着金铜矿分布。 相似文献
173.
尚钢 《武汉大学学报(信息科学版)》1998,(3)
将关于形状不变的自建模回归模型推广到多元自变量,解决了计算问题,并结合教育测量数据给出了实例。该模型既可以反映多条曲线走势的共性,又可以反映每条曲线之间的相互关系及其个性。 相似文献
174.
175.
THETHEORETICALSTUDYONTHELAWSOFDRAGREDUCTIONBYAERATIONINOPENCHANNEL1ZHENGYonggang2,FANGDuo3andLIGuifen4ABSTRACTThelawsofdragre... 相似文献
176.
铁路隧道的施工工程地质及围岩量测数据处理系统 总被引:1,自引:0,他引:1
吉随旺 《地质灾害与环境保护》1998,9(1):61-64
讨论了铁路隧道的施工工程地质工作的内容及必要性,并介绍围岩变形量测及其数据处理系统。 相似文献
177.
湖南省青山硫铁矿矿体形态较复杂 ,区内构造以断裂为主 ,溶洞发育。采用多层矿体房柱法开采 ,采矿顺序从上而下 ,由矿体两翼向轴部回采 ,使得井下围岩应力逐步向中央轴部集中 ,引起地压活动 ,导致坍塌事故 ,迫使矿山停产闭坑。改进采矿方法 ,改变回采顺序 ,加快回采速度 ,是有效地控制地压活动的主要方法。加强研究和观测 ,及时预报 ,采取措施 ,能避免地压活动引起突发性事故 ,防止造成不必要的损失 相似文献
178.
INVESTIGATION OF STATUS AND DEMAND ON PUBLIC SERVICE OF EARTHQUAKE DISASTER MITIGATION IN CHINA
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In order to make a comprehensive and systematic evaluation of the status and demands of public service of earthquake disaster mitigation, we launched an investigation with Social Opinion Polling Center of National Bureau of Statistics on the current situation of public service of earthquake disaster mitigation and the demands for it in 2018. The investigation was conducted for 18~75-year-old residents for both urban and rural areas in 31 provinces of China mainland using the Computer Assisted Telephone Interview(CATI)method and 20 078 valid samples were received in total. The questionnaire mainly includes two parts: the current situation assessment and the demand survey. The assessment of public service status consists of five indicators: earthquake emergency drill, knowledge publicity of earthquake prevention and disaster reduction, acquisition of earthquake information, reliability of information released by earthquake agencies, and overall satisfaction. The results indicate that only 27.4% of public have participated the earthquake emergency drill, and 73.5% of public have learned some knowledge about earthquake prevention and disaster reduction in different level. It shows that rural residents have a lower level of scientific knowledge of earthquake disaster mitigation although the rural residents have a higher level of satisfaction. Meanwhile, 82.9% of the public are very concerned about earthquake-related information, and the earthquake information acquisition convenience score is 81.51 points(the full score is 100 points). At present, TV is still the most popular way to obtain the earthquake-related information, besides that, network and the new media app such as Wechat and Weibo play a more and more important role. In terms of the reliability of official information published by the earthquake administration, the score is 83.69 points which indicates that the public tend to believe in official departments. Furthermore, the degree of satisfaction evaluation of public service of earthquake disaster mitigation is marked 76.44 points which shows that there is still much room for improvement. The more educated the public, the less satisfied they are with the public service of earthquake prevention and disaster reduction. The results also show that 51.81% of the public are willing to obtain earthquake warning information at their own expense. As for the demand, the most expectative services for the public are post-earthquake rescue and reconstruction, earthquake warning, and house earthquake resilience test. The results of the investigation may provide some reference for the government to provide better services of earthquake disaster mitigation and to make scientific knowledge popularization in a more scientific way. 相似文献
179.
180.
Leif Kahl Kristensen 《Celestial Mechanics and Dynamical Astronomy》2007,98(3):203-215
Initial asteriod orbits are determined by a least squares adjustment of an arbitrary number (N) of optical and radar observations. The usual separation, into an orbit determination by three observations and a subsequent
differential orbit improvement, is combined into a single algorithm. A priori information is used for very small arcs. Ephemerides
very suitable for linking are obtained by strictly linear computations. 相似文献