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Optimization of Shanghai marine environment monitoring sites by integrating spatial correlation and stratified heterogeneity 被引量:2
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作者 FAN Haimei GAO Bingbo +1 位作者 XU Ren WANG Jinfeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期111-121,共11页
The water quality grades of phosphate(PO4-P) and dissolved inorganic nitrogen(DIN) are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validat... The water quality grades of phosphate(PO4-P) and dissolved inorganic nitrogen(DIN) are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validation is used to determine the statistical inference method. To minimize absolute average errors and error mean squares,stratified Kriging(SK) interpolation is applied to DIN and ordinary Kriging(OK) interpolation is applied to PO4-P.Ten percent of the sites is adjusted by considering their impact on the change in deviations in DIN and PO4-P interpolation and the resultant effect on areas with different water quality grades. Thus, seven redundant historical sites are removed. Seven historical sites are distributed in areas with water quality poorer than Grade IV at the north and south branches of the Changjiang(Yangtze River) Estuary and at the coastal region north of the Hangzhou Bay. Numerous sites are installed in these regions. The contents of various elements in the waters are not remarkably changed, and the waters are mixed well. Seven sites that have been optimized and removed are set to water with quality Grades III and IV. Optimization and adjustment of unrestricted areas show that the optimized and adjusted sites are mainly distributed in regions where the water quality grade undergoes transition.Therefore, key sites for adjustment and optimization are located at the boundaries of areas with different water quality grades and seawater. 展开更多
关键词 area of water quality grade stratified Kriging(SK) leave-one-out cross validation method spatial simulated annealing method monitoring sites optimization
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Optimizing the atmospheric sampling sites using fuzzy mathe-matic methods
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作者 FANG Chun sheng WANG Ju +1 位作者 DONG De ming YU Lian sheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第4期464-468,共5页
A new approach applying fuzzy mathematic theorems, including the Primary Matrix Element Theorem and the Fisher Classification Method, was established to solve the optimization problem of atmospheric environmental samp... A new approach applying fuzzy mathematic theorems, including the Primary Matrix Element Theorem and the Fisher Classification Method, was established to solve the optimization problem of atmospheric environmental sampling sites. According to its basis, an application in the optimization of sampling sites in the atmospheric environmental monitoring was discussed. The method was proven to be suitable and effective. The results were admitted and applied by the Environmental Protection Bureau (EPB) of many cities of China. A set of computer software of this approach was also completely compiled and used. 展开更多
关键词 fuzzy set primary matrix element theorem fisher classification method optimization of sampling sites
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城镇应急资源储备点选址与布局优化研究:考虑暴雨灾害和路径长度 被引量:12
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作者 吴坷 宋英华 吕伟 《中国安全科学学报》 CAS CSCD 北大核心 2017年第9期170-174,共5页
针对城镇应急资源配送速度慢与交通组织通达性不通畅的问题,以暴雨灾害为背景,提出一种城镇应急资源储备点快速选取和布局优化的方法。该方法以武汉市洪山区为实例,首先从确定的暴雨灾害影响下应急资源储备点选址的6个基本条件中筛选出... 针对城镇应急资源配送速度慢与交通组织通达性不通畅的问题,以暴雨灾害为背景,提出一种城镇应急资源储备点快速选取和布局优化的方法。该方法以武汉市洪山区为实例,首先从确定的暴雨灾害影响下应急资源储备点选址的6个基本条件中筛选出研究区域中8个合适的应急资源储备点;然后运用弗洛依德算法计算由储备点出发的配送路径,以总路径距离最短为目标,得到这8个储备点当个数不同时其位置分布的关系。分析表明:增加储备点个数会减少配送路径总长度并提高配送效率,但当储备点超过5个后,增加储备点个数的意义已不明显,5是该区域的最佳储备点个数;该结论也适用于其他城市背景。 展开更多
关键词 城镇 应急资源 储备点 选址与布局 优化
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Center for Plant Conservation's Best Practice Guidelines for the reintroduction of rare plants 被引量:2
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作者 Joyce Maschinski Matthew A.Albrecht 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第6期390-395,共6页
Recent estimates indicate that one-fifth of botanical species worldwide are considered at risk of becoming extinct in the wild. One available strategy for conserving many rare plant species is reintroduction, which ho... Recent estimates indicate that one-fifth of botanical species worldwide are considered at risk of becoming extinct in the wild. One available strategy for conserving many rare plant species is reintroduction, which holds much promise especially when carefully planned by following guidelines and when monitored long-term. We review the Center for Plant Conservation Best Reintroduction Practice Guidelines and highlight important components for planning plant reintroductions. Before attempting reintroductions practitioners should justify them, should consider alternative conservation strategies, understand threats, and ensure that these threats are absent from any recipient site. Planning a reintroduction requires considering legal and logistic parameters as well as target species and recipient site attributes.Carefully selecting the genetic composition of founders, founder population size, and recipient site will influence establishment and population growth. Whenever possible practitioners should conduct reintroductions as experiments and publish results. To document whether populations are sustainable will require long-term monitoring for decades, therefore planning an appropriate monitoring technique for the taxon must consider current and future needs. Botanical gardens can play a leading role in developing the science and practice of plant reintroduction. 展开更多
关键词 REINTRODUCTION Monitoring GENETICS Optimal site selection FOUNDERS Managed relocation
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Effect of Intertidal Elevation at Tsuyazaki Cove,Fukuoka,Japan on Survival Rate of Horseshoe Crab Tachypleus tridentatus Eggs 被引量:1
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作者 ITAYA Shinji SHUUNO Mari +2 位作者 ONIKURA Norio TAI Akira YANO Shinichiro 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第3期601-610,共10页
Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg s... Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg survival rates per day were highest in the mid intertidal zone(45.1%±25.4%)and the lowest in the low intertidal zone(13.3%±27.6%).Differences in the elevation,air exposure time,and water content of the spawning ground were significant factors determining the egg survival rates.Excessive or insufficient air exposure time resulted in inadequate water content at higher and lower intertidal zones and could reduce egg survival.On the other hand,moderate saturation and dehydration were repeated with each tidal movement in the mid intertidal zone.This dynamic is considered as one of the crucial factors for the survival of eggs and is considered optimal for spawning.Therefore,the protection of the mid intertidal zone is imperative for maximizing the egg survival rate in Tsuyazaki Cove where almost all suitable nesting sites have disappeared due to coastal development.By protecting these optimal sites for spawning and recovering other optimal sites on suitable beaches,a positive contribution can be made to future management and conservation.The study also suggests that translocating eggs from marginal to optimal spawning sites might be a recovery strategy for this globally endangered species. 展开更多
关键词 air exposure time globally endangered species intertidal elevation intertidal zone optimal spawning site Tachypleus tridentatus translocated horseshoe crab eggs Tsuyazaki Cove
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Fe-N-C氧还原电催化剂中FeN_(4)位点微观环境的调节 被引量:2
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作者 王青 陆瑞虎 +10 位作者 杨予琪 李玄泽 陈广波 尚露 彭力山 Dongxiao Sun-Waterhouse Bruce C.C.Cowie 孟祥敏 赵焱 张铁锐 Geoffrey I.N.Waterhouse 《Science Bulletin》 SCIE EI CSCD 2022年第12期1264-1273,M0004,共11页
Fe-N-C电催化剂,即FeN_(4)单原子位点负载于氮掺杂的碳载体上,是一种优良的氧还原催化剂,有望取代贵金属铂催化剂,应用于金属空气电池和燃料电池.目前,提高Fe-N-C材料氧还原性能的策略包括:(1)提高铁单原子活性位点的数目;(2)调节铁单... Fe-N-C电催化剂,即FeN_(4)单原子位点负载于氮掺杂的碳载体上,是一种优良的氧还原催化剂,有望取代贵金属铂催化剂,应用于金属空气电池和燃料电池.目前,提高Fe-N-C材料氧还原性能的策略包括:(1)提高铁单原子活性位点的数目;(2)调节铁单原子中心与含氧中间体的吸附能,从而提高本征活性.该工作报道了一种简单NaCl熔盐煅烧Fe掺杂金属有机配合物前驱体(Fe-ZIF)的方法,可有效提高煅烧产物Fe-N-C催化剂中FeN_(4)单原子位点数量和本征活性.原位透射电子显微镜(TEM)实验结果表明:在高温煅烧过程中,NaCl蒸发后沉积附着在Fe-ZIF颗粒表面,加速Fe-ZIF中配体的分解和锌中心的挥发,从而使煅烧产物中碳载体呈多孔结构,并改变Fe单原子位点的配位环境.X射线吸收谱进一步表明,该Fe-N-C催化剂中Fe单原子位点的Fe-N键变长,Fe的氧化态降低,从而有利于氧还原反应中间体的脱附.因此,针对碱性氧还原反应过程,该催化剂表现出比商业化铂碳催化剂更优异的性能,并可作为锌空气电池阴极催化剂,用于手机充电. 展开更多
关键词 Fe-N-C MICROENVIRONMENT Optimized FeN_4 site Oxygen reduction reaction Zinc-air battery
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