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21.
通过对“辽宁省农村集体土地确权登记发证”项目0.2m分辨率航空遥感影像成果的检查验收,阐述了应用Leica ADS80系统生产航空遥感影像成果的检查内容、检查方法及质量控制的关键点,进而提出了航空遥感影像成果检查的技术核心。本文对于其它生产单位应用Leica ADS80系统生产的高分辨率航空遥感影像成果的检查验收提供了可以借鉴的经验。 相似文献
22.
Simulation of the Arabian Sea Tsunami propagation generated due to 1945 Makran Earthquake and its effect on western parts of Gujarat (India) 总被引:1,自引:1,他引:0
The 1945 Tsunami generated due to Makran Earthquake in the Arabian Sea was the most devastating tsunami in the history of
the Arabian Sea and caused severe damage to property and loss of life. It occurred on 28th November 1945, 21:56 UTC (03:26
IST) with a magnitude of 8.0 (M
w), originating off the Makran Coast of Pakistan in the Arabian Sea. It has impacted as far as Mumbai in India and was noticed
up to Karvar Coast, Karnataka. More than 4,000 people were killed as a result of the earthquake and the tsunami. In this paper
an attempt is made for a numerical simulation of the tsunami generation from the source, its propagation into the Arabian
Sea and its effect on the western coast of India through the use of a numerical model, referred to as Tunami-N2. The present
simulation is carried out for a duration of 300 min. It is observed from the results that the simulated arrival time of tsunami
waves at the western coast of India is in good agreement with the available data sources. The paper also presents run-up elevation
maps prepared using Shuttle Radar Topographic Mission (SRTM) data, showing the possible area of inundation due to various
wave heights along different parts of the Gujarat Coast. Thus, these results will be useful in planning the protection measures
against inundation due to tsunami and in the implementation of a warning system. 相似文献
23.
Kevin Leleu Frédérique AlbanDominique Pelletier Eric CharbonnelYves Letourneur Charles F. Boudouresque 《Marine Policy》2012,36(2):414-422
How users perceive the performance of Marine Protected Areas (MPAs) is fundamental for the social acceptance of these zones. Moreover, their perceptions may be relevant for monitoring the effects of MPAs on extractive activities. This study analyzes artisanal fishers' perceptions of the performance of a north-western Mediterranean coastal MPA, which encompasses two no-take zones (NTZs). Three viewpoints have been considered: the effect on the personal activity of fishers, the effect on the local fishery and the effect on the ecosystem. In order to test the hypothesis that biomass export (spillover) - which had previously been evidenced from the two NTZs - may influence fishers' perceptions of NTZ effects, fishers' perceptions were compared with both declared and observed fishing activity over an one-year period.The results show that negative perceptions of NTZs are either nil or are negligible. Most fishers are aware of the beneficial effects of NTZs on ecosystems and fisheries. However, they remain to be convinced of the beneficial effects of the NTZs on their own activity. For instance, the proximity of a NTZ appears never to be involved in the choice of a fishing spot. This partial lack of correspondence between scientific expectation and fishers' perceptions is discussed in the light of fishing habits in the zone adjacent to NTZs, and takes into account fishing grounds, targeted species and seniority (defined as the number of years the fisher has been fishing within the MPA). All three factors appear to influence fishers' perceptions. For example, having a positive perception about a NTZ and spending more time fishing in the adjacent zone are habits that can be associated with fishers with less seniority. Fishers' perceptions obviously indicate the social acceptance of the MPA and are an essential monitoring tool for MPA managers. However, perceptions cannot be seen as a substitute for scientific monitoring, as both approaches are clearly complementary. 相似文献
24.
现行《建筑边坡工程技术规范》存在着一些争议。规范中规定适用范围可为岩石基坑,但很多条款是针对边坡工程的,对基坑工程不适用,建议适用范围不要扩大到基坑;规定临时性边坡使用年限为2年,已不满足工程建设要求,建议提高为5年;几个术语定义不准确,宜重新定义;适用边坡高度及边坡安全等级已不满足工程建设要求,建议适当调整;滑塌区范围估算公式意义不大且有缺陷,建议取消;对坡率法适用范围限制过于严格,建议放宽;查坡率表设计法已过时,建议取消;规定锚杆基本试验时可将锚固段长度减短,但这样得到的极限粘结强度值偏高,将导致工程设计不安全,不能减短;锚杆验收试验标准不明确且应用困难,建议按相关原则重新编写等等。这些意见供规范修编时参考。 相似文献
25.
26.
通过对重塑粉质黏土的液、塑限和固结慢速直剪试验,探讨了粉质黏土液限、塑性指数及抗剪强度与不同浓度NaCl孔隙溶液的关系。试验结果表明,随着孔隙溶液浓度增加,液限随之减小,塑性指数表现出粉土的性质;不同竖向正应力下的强度随浓度变化表现出较大的差异,正应力较低时,强度不断减小,而正应力较高时,则强度不断增大,正应力介于二者之间强度则先降后升;内摩擦角随浓度增加而增大,最终趋于稳定;黏聚力先迅速减小后逐渐回升,且均为负值。其性质变化主要是因为扩散双电层、颗粒间作用力以及孔隙比发生了改变。基于Terzaghi的有效应力原理,对饱和粉质黏土固结慢速直剪试验测得的负值黏聚力进行了分析和讨论,认为渗透压力对黏聚力起了非常重要的作用,从而使黏聚力成为负值。 相似文献
27.
误差限的病态总体最小二乘解算 总被引:2,自引:2,他引:0
大地测量和地球物理数据解算中时常会涉及病态问题的处理。基于客观的观测精度,利用设计矩阵与观测向量的误差限制,一方面降低了病态性对求解造成的波动;另一方面避免引入正常数,从而提高整个解算过程的客观性与可靠性。计算表明,本文提出的方法可以有效地处理病态总体最小二乘问题,并且具有较高的稳定性。 相似文献
28.
29.
中国的生态补偿实施主要通过制度安排进行。在内蒙古农牧交错带,生态补偿主要通过两种模式进行,即对农牧户放弃土地使用和生产结构调整给予补偿。基于详尽的野外调查,本研究对农牧户经济受偿意愿进行了对比分析,并对两种生态补偿模式的效应进行了详细评价。结果表明,放弃土地使用的生态补偿模式缺乏创造就业机会的机制,因此不具有可持续性。与此相反,调整生产结构的补偿方式不但使农户从事农牧业的规模有了明显下降,而且有助于创造更多的就业机会。虽然这种模式会使农户面临很大的市场风险,但是它为解决区域生态系统恢复和社会经济发展之间的矛盾提供了一种有效方法。 相似文献
30.
Cengiz Kahraman İhsan Kaya 《Stochastic Environmental Research and Risk Assessment (SERRA)》2009,23(4):451-462
Water covers over 70% of the Earth surface and is a very important resource to people and the environment. Water pollution affects drinking water, rivers, lakes and oceans all over the world. This consequently harms human health and the natural environment. Water pollution can also affect the crops. So, water pollution is an important issue for humanity. Therefore, the control of irrigation water is a necessity. In this paper, a methodology based on process capability indices (PCIs) has been presented to control the levels of pH, dissolved oxygen (DO) and temperature (T) in dam’s water for irrigation. Fuzzy PCIs have been proposed for this aim. The fuzzy estimates of $ \hat C_p Water covers over 70% of the Earth surface and is a very important resource to people and the environment. Water pollution
affects drinking water, rivers, lakes and oceans all over the world. This consequently harms human health and the natural
environment. Water pollution can also affect the crops. So, water pollution is an important issue for humanity. Therefore,
the control of irrigation water is a necessity. In this paper, a methodology based on process capability indices (PCIs) has
been presented to control the levels of pH, dissolved oxygen (DO) and temperature (T) in dam’s water for irrigation. Fuzzy PCIs have been proposed for this aim. The fuzzy estimates of and are obtained for pH, DO, and T based on Buckley’s interval estimation approach and based on fuzzy specification limits. An application has been made for
Kesikk?prü Dam in Ankara, Turkey. In this paper, Buckley’s approach is re-arranged to obtain a triangular fuzzy membership
function because it cannot be obtained from Buckley’s approach in some situation. 相似文献