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Two-dimensional physical habitat modeling of effects of habitat structures on urban stream restoration 被引量:9
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作者 Dongkyun IM Hyeongsik KANG 《Water Science and Engineering》 EI CAS 2011年第4期386-395,共10页
River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is reco... River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA) using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity. 展开更多
关键词 stream restoration physical habitat River2D weighted usable area
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China Accelerating Development of Two Large Reusable Rocket Models
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《International Journal of Plant Engineering and Management》 2024年第1期63-64,共2页
BEIJING,March 12(Xinhua)——China′s development of both 4⁃meter⁃diameter and 5⁃meter⁃diameter reusable rockets is being accelerated,with their inaugural flights scheduled for 2025 and 2026,respectively.The manufactur... BEIJING,March 12(Xinhua)——China′s development of both 4⁃meter⁃diameter and 5⁃meter⁃diameter reusable rockets is being accelerated,with their inaugural flights scheduled for 2025 and 2026,respectively.The manufacturing of these two new large reusable launching vehicle models is a response to growing demand in the commercial space market,said the China Aerospace Science and Technology Corporation. 展开更多
关键词 ROCKET usable scheduled
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三江平原区域水资源分析(五) 被引量:2
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作者 郭大本 魏永霞 王清 《黑龙江大学工程学报》 1998年第1期10-14,共5页
This paper presents the systematic Summation of the investigation and the re-examination results,and the overall analysis of the quntity, quality, distribution, principle and way of development of water resource in Sa... This paper presents the systematic Summation of the investigation and the re-examination results,and the overall analysis of the quntity, quality, distribution, principle and way of development of water resource in Sanjiang plain. 展开更多
关键词 REGIONAL WATER resouree usable quantity ADVANTAGE EVALUATION
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谈壮语的可利用价值 被引量:3
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作者 罗起君 《河池师专学报》 2002年第3期77-80,共4页
本文提出壮语的三方面的可利用价值 :语言学习的参考价值 ;民族源流的左证价值 ;
关键词 壮语 可利用价值 英语教学 民族语言
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Agglomerative Approach for Identification and Elimination of Web Robots from Web Server Logs to Extract Knowledge about Actual Visitors 被引量:1
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作者 Dilip Singh Sisodia Shrish Verma Om Prakash Vyas 《Journal of Data Analysis and Information Processing》 2015年第1期1-10,共10页
In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of lear... In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of learner. We conduct a comparative study for various ensemble methods (Bagging, Boosting, and Voting) with simple classifiers in perspective of classification. We also evaluate the effectiveness of these classifiers (both ensemble and simple) on five different data sets of varying session length. Presently the results of web server log analyzers are not very much reliable because the input log files are highly inflated by sessions of automated web traverse software’s, known as web robots. Presence of web robots access traffic entries in web server log repositories imposes a great challenge to extract any actionable and usable knowledge about browsing behavior of actual visitors. So web robots sessions need accurate and fast detection from web server log repositories to extract knowledge about genuine visitors and to produce correct results of log analyzers. 展开更多
关键词 WEB Robots WEB Server Log REPOSITORIES Ensemble Learning Bagging Boosting and Voting Actionable KNOWLEDGE usable KNOWLEDGE Browsing Behavior GENUINE VISITORS
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基于聚类分析在老年易用性产品设计中的应用 被引量:2
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作者 张静 颜妗真 《设计》 2022年第11期122-125,共4页
为了解决老年人群对产品易用性功能满意度低的问题,分析用户使用体验与产品功能之间的对映关系,改良设计符合老年消费人群使用的产品。通过调研,分析现有产品的使用感受,采用聚类分析方法,对产品使用需求元素进行分组、聚类,提取老年人... 为了解决老年人群对产品易用性功能满意度低的问题,分析用户使用体验与产品功能之间的对映关系,改良设计符合老年消费人群使用的产品。通过调研,分析现有产品的使用感受,采用聚类分析方法,对产品使用需求元素进行分组、聚类,提取老年人群的需求,分析用户需求与产品造型设计达之间的关系。以老年人群使用的血压仪为例,设计符合老年人群生理特征的产品,从而实现产品的易用性设计。实践结果表明,运用聚类分析方法可以有效提升产品的易用性功能,可以作为产品设计的一种新方法。 展开更多
关键词 聚类分析 老年 易用性 设计 产品
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A high-precision hydrodynamic model coupled with the hydrological habitat suitability model to reveal estuarine vegetation distribution 被引量:2
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作者 Qiao-feng Ma Shu-xiu Liang +3 位作者 Zhao-chen Sun Wen-hao Hou Xin-yue Hu Rui-jin Zhang 《Journal of Hydrodynamics》 SCIE EI CSCD 2022年第3期451-466,共16页
In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a grap... In this paper,based on the finite volume method,a high-precision hydrodynamic model coupled with the habitat suitability model is established,and the computational efficiency of the coupled model is improved by a graphics processing unit(GPU)-accelerated technology.The coupled model is used to solve the problem of the non-conservation of mass that may be caused by the nearshore hydrodynamic model in the processing of wetting and drying,while avoiding the unphysical high velocities at the wetting and drying boundaries.The coupled model is applied to simulate the high-precision hydrodynamic process of the Liao River estuary(LRE)and the hydrological habitat suitability of the estuarine vegetation(Suaeda heteroptera)growing in the LRE.The simulated values of the hydrological variables(the water level,the water depth,the current velocity and direction)are highly consistent with the measured values.The root mean square errors(RMSE)of the hydrological variables are 0.10m,0.12m/s and 17.24°,respectively.Furthermore,the simulated combined suitability index(CSI)distribution of Suaeda heteroptera(S.heteroptera)matches with the distribution of S.heteroptera obtained from the high-resolution remote sensing satellite images during the same time period.The ratio of the simulated weighted usable area(WUA)of S.heteroptera to the area obtained from the remote sensing satellite images during the same period is 81.9%.This study reveals the phenomenon that the distribution of S.heteroptera in the LRE is highly correlated with the high-precision hydrodynamic processes,and provides a scientific basis and a valuable reference for the conservation and the restoration of the estuarine vegetation. 展开更多
关键词 High-precision hydrodynamic model habitat suitability model conversation of mass weighted usable area vegetation distribution
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Design of Secure and Traceable Requirement Engineering Process for Security-Sensitive Projects
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作者 Abdul Ahad Luqman Tariq +1 位作者 Saba Niaz Muhammad Inam 《Journal of Software Engineering and Applications》 2017年第12期873-883,共11页
With continuous evolution in software industry, security is becoming very important in software projects. However, in many development methodologies, security is thought to be added in the project at later stages of t... With continuous evolution in software industry, security is becoming very important in software projects. However, in many development methodologies, security is thought to be added in the project at later stages of the development lifecycle. There are also many proposed methodologies where the security measures are considered at requirement engineering stage of the development lifecycle, but many of them still do not seem adequate for applicability due to the reason that these approaches do not provide sufficient support for mapping the security requirements to the later stages of development. So, we are in need of a software requirement engineering approach, which is not only helpful in security requirement specification at requirement engineering stage but also provides support for using the specified security requirements at later stages of development. To meet this requirement, we introduce a new method Secure and Traceable Requirement Engineering Process (STREP). This method also helps the non-security-expert requirement engineers to specify requirements in such a way that the specified requirements can be used to derive security related test cases. STREP method not only deals with security issues of the system at requirement engineering stage, but also makes the security requirements more traceable to be used at later stages of development lifecycle, and as a result, secure systems are produced that are also usable as the customer wishes. 展开更多
关键词 TRACEABLE usable SECURITY Requirements REQUIREMENT Specification Development LIFECYCLE SRE Method
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Graph-based visual analytics for cyber threat intelligence 被引量:2
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作者 Fabian Bohm Florian Menges Gunther Pernul 《Cybersecurity》 2018年第1期279-297,共19页
The ever-increasing amount of major security incidents has led to an emerging interest in cooperative approaches to encounter cyber threats.To enable cooperation in detecting and preventing attacks it is an inevitable... The ever-increasing amount of major security incidents has led to an emerging interest in cooperative approaches to encounter cyber threats.To enable cooperation in detecting and preventing attacks it is an inevitable necessity to have structured and standardized formats to describe an incident.Corresponding formats are complex and of an extensive nature as they are often designed for automated processing and exchange.These characteristics hamper the readability and,therefore,prevent humans from understanding the documented incident.This is a major problem since the success and effectiveness of any security measure rely heavily on the contribution of security experts.To meet these shortcomings we propose a visual analytics concept enabling security experts to analyze and enrich semi-structured cyber threat intelligence information.Our approach combines an innovative way of persisting this data with an interactive visualization component to analyze and edit the threat information.We demonstrate the feasibility of our concept using the Structured Threat Information eXpression,the state-ofthe-art format for reporting cyber security issues. 展开更多
关键词 Cyber threat intelligence Visual analytics usable cybersecurity STIX
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Criterion of aerodynamic performance of large-scale offshore horizontal axis wind turbines
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作者 程兆雪 李仁年 +1 位作者 杨从新 胡文瑞 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第1期13-20,共8页
With the background of offshore wind energy projects, this paper studies aerodynamic performance and geometric characteristics of large capacity wind turbine rotors (1 to 10 MW), and the main characteristic paramete... With the background of offshore wind energy projects, this paper studies aerodynamic performance and geometric characteristics of large capacity wind turbine rotors (1 to 10 MW), and the main characteristic parameters such as the rated wind speed, blade tip speed, and rotor solidity. We show that the essential criterion of a high- performance wind turbine is a highest possible annual usable energy pattern factor and a smallest possible dimension, capturing the maximum wind energy and producing the maximum annual power. The influence of the above-mentioned three parameters on the pattern factor and rotor geometry of wind turbine operated in China's offshore meteoro- logical environment is investigated. The variation patterns of aerodynamic and geometric parameters are obtained, analyzed, and compared with each other. The present method for aerodynamic analysis and its results can form a basis for evaluating aerodynamic performance of large-scale offshore wind turbine rotors. 展开更多
关键词 offshore wind energy project horizontal axis wind turbine rotor aerody-namic design annual usable energy pattern factor power coefficient wind turbine rotor wind turbine blade
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Estimating Usable-Security Through Hesitant Fuzzy Linguistic Term Sets Based Technique
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作者 Abdulaziz Attaallah Raees Ahmad Khan 《Computers, Materials & Continua》 SCIE EI 2022年第3期5683-5705,共23页
The apparent contradiction between usability and security has been discussed in the literature for several years.This continuous trade-off requires be acknowledging and handling whenever security solutions are introdu... The apparent contradiction between usability and security has been discussed in the literature for several years.This continuous trade-off requires be acknowledging and handling whenever security solutions are introduced.However,some progressive analysts point out that present security solutions are usually very difficult for several users,and they have expressed a willingness to simplify the security product user experience.Usable security is still mostly unexplored territory in computer science.Which we are all aware with security and usability on many levels,usable security has received little operational attention.Companies have recently focused primarily on usable security.As consumers prefer to discard unsatisfactory solutions,attaining well-balanced degrees of both is a prerequisite for adequate security.Usability should be examined from the viewpoint of security to be properly assessed.The aim of this research study is to explore and discuss universally accepted and solutionindependent factors influencing the perceived usable-security of institutional websites.An integrated Hesitant Fuzzy Linguistic term sets based technique was chosen as the methodology,and the experts and academicians opinion were collected.The use of predetermined selection criteria resulted in the compilation of statistical findings and were used to determine the usable-security of five different instituational websites. 展开更多
关键词 usable security ACCESSIBILITY expert evaluation usability criteria fuzzy logic
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Promoting International Cooperation on Nuclear Security
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作者 Page O Stoutland 《Peace》 2014年第2期54-55,共2页
If terrorists can obtain a sufficient quantity of weapons usable nuclear material,they could design,construct and detonate a nuclear bomb.The consequences of such a catastrophe would reverberate around the globe,with ... If terrorists can obtain a sufficient quantity of weapons usable nuclear material,they could design,construct and detonate a nuclear bomb.The consequences of such a catastrophe would reverberate around the globe,with thousands of casualties,disruptions to economic markets,long-term implications for public health and the environment,and risks to civil liberties-not to mention the staggering cost of any response. 展开更多
关键词 NUCLEAR consequences usable CIVIL COOPERATION glob
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Development of Bioinfo-Portal Tool for the Analysis of Genomic and Proteomic Data
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作者 Rana Rehan Khalid Bilal Hussain +3 位作者 Muhammad Ali Muhammad Sajjad Ahmad Asma Haque Hira Qamar 《Journal of Life Sciences》 2012年第5期485-488,共4页
The recent explosion of biological data and the concomitant proliferation of distributed databases make it challenging for biologists and bioinformaticians to discover the best data resources for their needs, and the ... The recent explosion of biological data and the concomitant proliferation of distributed databases make it challenging for biologists and bioinformaticians to discover the best data resources for their needs, and the most efficient way to access and use them For the biologist, running bioinformatics analyses involve a time-consuming management of data and tools. Users need support to organize their work, retrieve parameters and reproduce their analyses. They also need to be able to combine their analytic tools using a safe data flow software mechanism. Finally we have designed a system, Bioinfo-Portal, to provide a flexible and usable web environment for defining and running bioinformatics analyses. It embeds simple yet powerful data management features that allow the user to reproduce analyses and to combine tools using an adobe flex tool. Bioinfo-Portal can also act as a front end to provide a unified view of already-existing collections of bioinformatics resources. Users can analyze genomic and proteomic data by using the tools that has been integrated in the portal (tools for alignments, dotplots, motif detection, domain analysis, profile searching and tertiary structure prediction). The sequences that user obtained from portal's nucleotide and protein databases are easily analyzed by the portal tools on the same interface in no time. User can also take benefit from the animations. 展开更多
关键词 Bioinfo-Portal analytic tools flexible and usable web environment tertiary structure prediction domain analysis motifdetection alignments.
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10 Breakthrough Technologies 2015
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《China Rare Earth Information》 2015年第3期3-6,共4页
Source:MIT Technology ntroduction Not all breakthroughs are created equal.Some arrive more or less as usable things;others mainly set the stage for innovations that emerge later,and we have to estimate when that will ... Source:MIT Technology ntroduction Not all breakthroughs are created equal.Some arrive more or less as usable things;others mainly set the stage for innovations that emerge later,and we have to estimate when that will be.But we’d bet that every one of the milestones on this list will be worth following in the coming years.1.Magic 展开更多
关键词 usable created THINGS Magic arrive emerge COMING IMAGERY EDUCATIONAL GENOMICS
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The Purchase of the Louisiana Territory
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作者 杨玉伟 《中学英语园地(高二版)》 2006年第5期19-20,共2页
In 1803, the USA paid France $15,000,000 for the Louisiana Territory(地域, 领土), an area more than four times the size of France. The land which was bought included everything between the Rocky Mountains and the Miss... In 1803, the USA paid France $15,000,000 for the Louisiana Territory(地域, 领土), an area more than four times the size of France. The land which was bought included everything between the Rocky Mountains and the Mississippi River except Texas. The main port for the second longest river system in the world was within this territory. Although few realized it at that time, the purchase included the vast forests of Arkansas and Minnesota, the oilfields of Oklahoma, the cornfields of Iowa, the wheat lands of the Dakotas, the copper, silver, and gold of Colorado and Montana, the rice and sugar of Louisiana. Without doubt, the Louisiana Purchase was one of the greatest events in the history of the United States. In a single action, as planned, a thirdclass nation successfully doubled its size, united its states and population, and became a great power in the world. 展开更多
关键词 GOODS LIVED PURCHASE SHIPPING tobacco usable getti
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理工科大学生英语词汇水平研究 被引量:95
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作者 马广惠 《外语教学》 北大核心 2001年第2期48-52,共5页
本文对我国非英语专业学生的大学英语词汇水平进行了多层面、多因素的实证研究。研究对象是我国三所高校的 133名理工科大学生。研究结果显示 ,我国学生在大学英语学习期间 ,英语词汇水平提高速度比较低。学生的大学英语词汇水平与大纲... 本文对我国非英语专业学生的大学英语词汇水平进行了多层面、多因素的实证研究。研究对象是我国三所高校的 133名理工科大学生。研究结果显示 ,我国学生在大学英语学习期间 ,英语词汇水平提高速度比较低。学生的大学英语词汇水平与大纲的要求尚有相当大的差距。本研究还发现 ,重点院校学生的词汇水平显著高于非重点院校的学生 ,女生的词汇水平显著高于男生。学校和性别在词汇水平上的差异 ,在很大程度上体现在中级词汇水平上。 展开更多
关键词 领会词汇 使用词汇 词汇水平
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西北地区水资源可利用量与承载能力估算 被引量:55
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作者 贾绍凤 周长青 +3 位作者 燕华云 周宏飞 汤奇成 张捷斌 《水科学进展》 EI CAS CSCD 北大核心 2004年第6期801-807,共7页
界定了水资源可利用量和径流口径生态需水的概念。对西北地区的径流口径生态需水和水资源可利用量进行估算。西北地区水资源总量为1638 5×108m3,但需净出境水量为411 9×108m3,实有水资源总量为1226 6×108m3,径流口径生... 界定了水资源可利用量和径流口径生态需水的概念。对西北地区的径流口径生态需水和水资源可利用量进行估算。西北地区水资源总量为1638 5×108m3,但需净出境水量为411 9×108m3,实有水资源总量为1226 6×108m3,径流口径生态需水量为454 4×108m3,除去保留给生态的生态需水、偏远封闭流域难以利用的水量,人类可以消耗利用的可利用量有742×108m3,其中黄河流域可利用量为187×108m3,西北内流区当地可利用量为555×108m3。建立了水资源承载能力优化计算模型,估算西北地区的水资源承载能力,并建议用水资源承载能力图谱表示水资源承载能力。在人均GDP每10年翻一番、水资源利用效率每年提高7%的条件下,西北地区水资源承载能力2010年为11310万人,2020年为12019万人,2030年为12733万人。 展开更多
关键词 水资源可利用量 生态需水量 水资源承载能力 西北地区
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基于物理栖息地模拟的河道内生态流量研究 被引量:55
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作者 张文鸽 黄强 蒋晓辉 《水科学进展》 EI CAS CSCD 北大核心 2008年第2期192-197,共6页
结合物理栖息地模拟模型的水力学与栖息地模型,以黄河干流兰州-石嘴山河段为研究样区及该河段的关键鱼种黄河鲤鱼为对象物种,以流速及水深二水力学因子进行研究,推求该研究样区兰州、安宁渡、下河沿、青铜峡和石嘴山五断面对象物种的流... 结合物理栖息地模拟模型的水力学与栖息地模型,以黄河干流兰州-石嘴山河段为研究样区及该河段的关键鱼种黄河鲤鱼为对象物种,以流速及水深二水力学因子进行研究,推求该研究样区兰州、安宁渡、下河沿、青铜峡和石嘴山五断面对象物种的流量与权重可使用面积的关系。通过对上述各断面1975-1985年汛前共11年生态、水文及断面资料的分析计算,归纳出研究断面汛前适合的生态流量分别为195、220、220、220、175 m3/s,计算结果在Tennant法界定的生态流量范围之内。 展开更多
关键词 河道 生态流量 物理栖息地 水深 流速 权重可使用面积
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水资源可利用量估算初步分析 被引量:37
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作者 郭周亭 《水文》 CSCD 北大核心 2001年第5期23-26,共4页
水资源可利用量的概念、内涵、影响因素和制约条件都是研究可利用量计算方法所不可忽视的前提,探讨一种可行的计算方法,对水资源开发利用、区域工程规划、经济发展规划具有重要意义。通过对水资源开发利用程度及其发展状况分析研究,提... 水资源可利用量的概念、内涵、影响因素和制约条件都是研究可利用量计算方法所不可忽视的前提,探讨一种可行的计算方法,对水资源开发利用、区域工程规划、经济发展规划具有重要意义。通过对水资源开发利用程度及其发展状况分析研究,提出了不同开发利用条件下的计算方法。 展开更多
关键词 水资源 可利用量 地表水 地下水 可开采量
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基于物理栖息地模拟的长江中游生态流量研究 被引量:43
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作者 李建 夏自强 《水利学报》 EI CSCD 北大核心 2011年第6期678-684,共7页
将Delft3D水力学模型和栖息地模型组成物理栖息地模拟模型以研究鱼类的生态环境。以长江中游宜昌至枝江河段为研究区域,以长江的重要经济鱼类四大家鱼为目标物种,结合流速及水深两个栖息地限制因子计算研究区域内不同流量下四大家鱼4个... 将Delft3D水力学模型和栖息地模型组成物理栖息地模拟模型以研究鱼类的生态环境。以长江中游宜昌至枝江河段为研究区域,以长江的重要经济鱼类四大家鱼为目标物种,结合流速及水深两个栖息地限制因子计算研究区域内不同流量下四大家鱼4个产卵场的栖息地面积,得到了流量与栖息地面积关系曲线。分析该曲线,结果表明:长江中游四大家鱼4—6月份产卵期间的最小生态流量为4570m3/s,适宜生态流量范围为12000~15500m3/s。计算结果在传统水文学法界定的生态流量范围之内,分析认为该计算结果更加合理,可为四大家鱼的保护和三峡及葛洲坝工程的生态调度提供参考建议。 展开更多
关键词 物理栖息地 生态流量 加权可利用面积 数值模拟
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