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Spatio-temporal Evolution of Marine Fishery Industry Ecosystem Vulnerability in the Bohai Rim Region 被引量:5
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作者 LI Bo JIN Xiaoming 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1052-1064,共13页
The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this p... The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery.Taking vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to 2015.The results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend;2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the west.According to the evolution track of the system’s vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into ‘declining’ and ‘stable’ types of evolutionary structures;3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery’s ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery’s science and technology talents, etc.Then, the marine fishery’s development in the Bohai Rim Region will be moving in the green, circular and sustainable direction. 展开更多
关键词 MARINE FISHERY MARINE INDUSTRY ecosystem vulnerability spatio-temporal EVOLUTION Bohai RIM region
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Spatio-Temporal Impact of Rural Livelihood Capital on Labor Migra- tion in Panxi, Southwestern Mountainous Region of China 被引量:5
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作者 WAN Jiangjun DENG Wei +4 位作者 SONG Xueqian LIU Ying ZHANG Shaoyao SU Yi LU Yafeng 《Chinese Geographical Science》 SCIE CSCD 2018年第1期153-166,共14页
Labor migration to urban centers is a common phenomenon in the Panxi region of the southwestern mountainous region of China, mainly owing to inadequate livelihood capital in rural areas. Numerous studies have been con... Labor migration to urban centers is a common phenomenon in the Panxi region of the southwestern mountainous region of China, mainly owing to inadequate livelihood capital in rural areas. Numerous studies have been conducted to explore the relationship between labor migration and its causes, such as individual and family characteristics, but few studies have focused on livelihood capital. This paper examines the impact factors on labor migration employment location selection and duration from a household livelihood capital perspective. A case study of 279 households from 10 villages in the area was carried out in February 2016. We used both qualitative and quantitative methods to analyze the data. On the basis of the 279 questionnaires, the proportion of households with non-labor migration is 48.4%, whereas households with labor migration within a local city and migration across regions account for 28.7% and 22.9%, respectively. Social, financial, and human capitals are the primary factors that influence migrants' employment location choice positively. Among them, social capital has a significant impact on both migration within a local city and across regions; each of the regression coefficients is 1.111 and 1.183. Social, human, and financial capitals also have a positive impact on the duration of labor migration, and similarly, social capital is the highest coefficient with 2.489. However, physical capital only partly impacts labor migration across regions, whereas the impact of labor migration within a local city, and the duration, are not significant. Furthermore, the impact of household natural capital on migration space and time are all negative relationships, especially for labor migration across the regions and duration, with coefficient scores of 4.836 and 3.450, respectively. That is to say, a laborer is inclined to migrate within a local city for a short term, or not migrate at all, if natural capital is abundant. Our analysis results show that household livelihood capital has a strong spatio-temporal impact on labor migration. 展开更多
关键词 labor migration livelihood capital spatio-temporal impact southwestern mountainous region China
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Spatio-temporal Variations of Temperature and Precipitation During 1951–2019 in Arid and Semiarid Region, China 被引量:2
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作者 HUANG Yufei LU Chunyan +3 位作者 LEI Yifan SU Yue SU Yanlin WANG Zili 《Chinese Geographical Science》 SCIE CSCD 2022年第2期285-301,共17页
Understanding the spatio-temporal variations of temperature and precipitation in the arid and semiarid region of China(ASRC)is of great significance for promoting regional eco-environmental protection and policy-makin... Understanding the spatio-temporal variations of temperature and precipitation in the arid and semiarid region of China(ASRC)is of great significance for promoting regional eco-environmental protection and policy-making.In this study,the annual and seasonal spatio-temporal patterns of change in average temperature and precipitation and their influencing factors in the ASRC were analyzed using the Mann-Kendall test,linear tendency estimation,accumulative anomaly and the Pearson’s correlation coefficient.The results showed that both annual average temperature and average annual precipitation increased in the ASRC during 1951–2019.The temperature rose by about 1.93℃and precipitation increased by about 24 mm.The seasonal average temperature presented a significant increase trend,and the seasonal precipitation was conspicuous ascension in spring and winter.The spatio-temporal patterns of change in temperature and precipitation differed,with the southwest area showing the most obvious variation in each season.Abrupt changes in annual and seasonal average temperature and precipitation occurred mainly around the 1990 s and after 2000,respectively.Atmospheric circulation had an important effect on the trends and abrupt changes in temperature and precipitation.The East Asian summer monsoon had the largest impact on the trend of average annual temperature,as well as on the abrupt changes of annual average temperature and precipitation.Temperature and precipitation changes in the ASRC were influenced by long-term and short-term as well as direct and indirect anthropogenic and natural factors.This study identifies the characteristics of spatio-temporal variations in temperature and precipitation in the ASRC and provides a scientific reference for the formulation of climate change responses. 展开更多
关键词 multi-source remote sensing data TEMPERATURE PRECIPITATION arid and semiarid region spatio-temporal variation atmospheric circulation
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Methods to evaluate the impacts of physio- geographical pattern on spatio-temporal disparity of regional development 被引量:1
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作者 LI Guosheng GUO Zhaocheng LIAO Heping 《Journal of Geographical Sciences》 SCIE CSCD 2008年第2期225-236,共12页
With the rapid economic development during the last 30 years in China, more and more disparities have emerged among different regions. It has been one of the hot topics in the fields of physical geography and economic... With the rapid economic development during the last 30 years in China, more and more disparities have emerged among different regions. It has been one of the hot topics in the fields of physical geography and economic geography, and also has been the task for Chinese government to handle. Nevertheless, to quantitatively assess the impacts of physio-geographical patterns (PGP) on the regional development disparity has been ignored for a long time. In this paper, a quantitative method was adopted to assess the marginal effects of the PGP on spatio-temporal disparity using the partial determination coefficients. The paper described the construction of the evaluation model step by step following its key scientific thinking. Total GDP, per capita GDP, primary industrial output value and secondary industrial output value were employed in this study as the indicators to reflect the impacts of PGP on the regional development disparity. Based on the evaluation methods built by researchers, this study firstly analyzed the temporal impacts of the PGP on spatio-temporal disparity of the regional development in China during the past 50 years, and then explained the spatial differences at each development stage. The results show that the spatio-temporal disparity in China is highly related to the PGP, and that the marginal contribution rate could be employed as an effective way to quantitatively assess the impact of the PGP on spatio-temporal disparity of the regional development. 展开更多
关键词 physio-geographical pattern regional development spatio-temporal disparity marginal contribution rate
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Multi-scale regionalization based mining of spatio-temporal teleconnection patterns between anomalous sea and land climate events
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作者 XU Feng SHI Yan +3 位作者 DENG Min GONG Jian-ya LIU Qi-liang JIN Rui 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2438-2448,共11页
Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-de... Climate sequences can be applied to defining sensitive climate zones, and then the mining of spatio-temporal teleconnection patterns is useful for learning from the past and preparing for the future. However, scale-dependency in this kind of pattern is still not well handled by existing work. Therefore, in this study, the multi-scale regionalization is embedded into the spatio-temporal teleconnection pattern mining between anomalous sea and land climatic events. A modified scale-space clustering algorithm is first developed to group climate sequences into multi-scale climate zones. Then, scale variance analysis method is employed to identify climate zones at characteristic scales, indicating the main characteristics of geographical phenomena. Finally, by using the climate zones identified at characteristic scales, a time association rule mining algorithm based on sliding time windows is employed to discover spatio-temporal teleconnection patterns. Experiments on sea surface temperature, sea level pressure, land precipitation and land temperature datasets show that many patterns obtained by the multi-scale approach are coincident with prior knowledge, indicating that this method is effective and reasonable. In addition, some unknown teleconnection patterns discovered from the multi-scale approach can be further used to guide the prediction of land climate. 展开更多
关键词 CLIMATE sequences ANOMALOUS climatic EVENTS spatio-temporal teleconnection patterns MULTI-SCALE regionALIZATION
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AN H_∞ FUZZY TRACKING CONTROL SCHEME FOR AFFINE COUPLED SPATIO-TEMPORAL CHAOS
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作者 DouChunxia ZhangShuqing 《Journal of Electronics(China)》 2005年第1期59-65,共7页
Due to the interactions among coupled spatio-temporal subsystems and the constant bias term of affine chaos, it is difficult to achieve tracking control for the affine coupled spatiotemporal chaos. However, every subs... Due to the interactions among coupled spatio-temporal subsystems and the constant bias term of affine chaos, it is difficult to achieve tracking control for the affine coupled spatiotemporal chaos. However, every subsystem of the affine coupled spatio-temporal chaos can be approximated by a set of fuzzy models; every fuzzy model represents a linearized model of the subsystem corresponding to the operating point of the controlled system. Because the consequent parts of the fuzzy models have a constant bias term, it is very difficult to achieve tracking control for the affine system. Based on these fuzzy models, considering the affine constant bias term, an H∞ fuzzy tracking control scheme is proposed. A linear matrix inequality is employed to represent the feedback controller, and parameters of the controller are achieved by convex optimization techniques. The tracking control for the affine coupled spatio-temporal chaos is achieved, and the stability of the system is also guaranteed. The tracking performances are testified by simulation examples. 展开更多
关键词 Coupled spatio-temporal chaos fuzzy model H∞ fuzzy tracking control Linear Matrix Inequality(LMI)
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Applying the AHP-FUZZY method to evaluate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau: a case study of Chaidaer-Muli Railway 被引量:1
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作者 Wei Cao Yu Sheng +1 位作者 Ji Chen JiChun Wu 《Research in Cold and Arid Regions》 CSCD 2018年第6期447-457,共11页
This article attempts to investigate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau. As a case study, Chaidaer-Muli Railway is used to evaluate the measure effect of ru... This article attempts to investigate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau. As a case study, Chaidaer-Muli Railway is used to evaluate the measure effect of rubble roadbed engineering in permafrost regions. The AHP(Analytic Hierarchy Process) method is thus employed to establish the evaluation indicator system. The evaluation factor is selected by analyzing the mutual relation between the permafrost environment and roadbed engineering. Thus, a hierarchical structure model is established based on the selected evaluation indices. Each factor is weighted to determine the status in the evaluation system, and grading standards are built for providing a basis for the evaluation. Then, the fuzzy mathematical method is introduced to evaluate the measure effect of rubble roadbed engineering in permafrost regions along the Chadaer-Muli Railway. Results show that most of the permafrost roadbed is in a preferable condition(b) along the Chaidaer-Muli Railway due to rubble engineering measures. This proportion reaches to 86.1%. The proportion in good(a), general(c) and poor states(d) are 0.0%, 7.5% and 6.4%, respectively, in all the evaluation sections along the Chaidaer-Muli Railway. Ground-temperature monitoring results are generally consistent with AHP-FUZZY evaluation results. This means that the AHP-FUZZY method can be applied to evaluate the effect of rubble roadbed engineering measures in permafrost regions. The effect evaluation of engineering measures will provide timely and effective feedback information for further engineering design. The series of engineering measures will more effectively protect permafrost stability. 展开更多
关键词 measure effect evaluation rubble roadbed engineering permafrost regions of Qinghai-Tibet Plateau AHP-fuzzy method Chaidaer-Muli Railway
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EVOLUTIONARY FUZZY GUIDANCE LAW WITH SELF-ADAPTIVE REGION 被引量:3
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作者 邹庆元 姜长生 吴柢 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期234-240,共7页
Effective guidance is one of the most important tasks to the performance of air-to-air missile. The fuzzy logic controller is able to perform effectively even in situations where the information about the plant is ina... Effective guidance is one of the most important tasks to the performance of air-to-air missile. The fuzzy logic controller is able to perform effectively even in situations where the information about the plant is inaccurate and the operating conditions are uncertain. Based on the proportional navigation, the fuzzy logic and the genetic algorithm are combined to develop an evolutionary fuzzy navigation law with self-adapt region for the air-to-air missile guidance. The line of sight (LOS) rate and the closing speed between the missile and the target are inputs of the fuzzy controller. The output of the fuzzy controller is the commanded acceleration. Then a nonlinear function based on the conventional fuzzy logic control is imported to change the region. This nonlinear function can be changed with the input variables. So the dynamic change of the fuzzy variable region is achieved. The guidance law is optimized by the genetic algorithm. Simulation results of air-to-air missile attack using MATLAB show that the method needs less acceleration and shorter flying time, and its realization is simple.[KH*3/4D] 展开更多
关键词 guidance law fuzzy logic genetic algorithm self-adaptive region
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基于模糊数学(Fuzzy)法的中国水稻土肥力质量近30年的时空变化特征 被引量:3
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作者 黄晶 韩天富 +7 位作者 申哲 柳开楼 马常宝 王慧颖 曲潇琳 于子坤 谢建华 张会民 《土壤学报》 CAS CSCD 北大核心 2023年第2期355-366,共12页
基于农业农村部在我国主要稻区的长期定位监测数据(1988—2017年),采用模糊数学(Fuzzy)法对水稻土肥力质量进行评价,并结合地统计学和机器学习,阐明我国水稻土肥力质量时空变化特征及其影响因素。近30 a来全国稻区土壤肥力质量呈显著上... 基于农业农村部在我国主要稻区的长期定位监测数据(1988—2017年),采用模糊数学(Fuzzy)法对水稻土肥力质量进行评价,并结合地统计学和机器学习,阐明我国水稻土肥力质量时空变化特征及其影响因素。近30 a来全国稻区土壤肥力质量呈显著上升趋势(P<0.05),从前期(1988—1999年)至中期(2000—2009年)和从中期至近期(2010—2017年),全国稻田土壤肥力指数(SFI)分别平均增加了6.9%和17.7%。各稻区SFI阶段性变化特征存在差异,西南和长江中游稻区呈前慢后快的显著上升趋势(P<0.05),华南和长江三角洲(长三角)稻区呈前快后稳的上升趋势,东北稻区呈前降后升的变化趋势。近期全国稻田SFI呈现北高南低、东高西低的分布特征,SFI超过全国平均值(0.61)的区域占50.2%。与中期相比较,近期全国稻区SFI总体呈上升趋势,SFI增加的区域占69.3%。各稻区在前期和中期(东北稻区的中期除外)均表现为土壤有机质和全氮影响SFI变化的相对重要性占比(19.4%~60.3%)远大于其他指标(0.1%~13.3%)。至近期,所有稻区各指标影响SFI变化的相对重要性占比差距缩小(7.4%~26.8%),土壤有效磷和速效钾及土壤pH(东北稻区pH除外)等指标的相对重要性增加,其中长江中游稻区土壤有效磷含量的相对重要性增至最大,但各稻区仍均以土壤全氮和有机质含量的相对重要性较大。综上,应综合考虑不同阶段和不同稻区土壤肥力质量时空差异特征及其关键肥力指标相对重要性的变化,针对性地优化施肥措施,防治水稻土酸化,以改善和提高水稻土肥力质量。 展开更多
关键词 水稻土 主要稻区 模糊数学(fuzzy)法 土壤肥力指数 时空变化 增强回归树
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Seismic Activity and Fuzzy Comprehensive Evaluation of Crustal Stability in the Beijing Region
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作者 Huang Qinghua, Ma Yinsheng, Institute of Geomechanics, C hinese Academy of Geological Science, Beijingand Song Xinchu Seismological Bureau of Zhejiang Province, Hangzhou, Zhejiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1994年第1期1-13,共13页
This paper discusses the seismic activity in Beijing M unicipality and its adjacent areas (which are referred to as the Beijing region in the paper). By using fuzzy mathematics, the factors controlling regional crusta... This paper discusses the seismic activity in Beijing M unicipality and its adjacent areas (which are referred to as the Beijing region in the paper). By using fuzzy mathematics, the factors controlling regional crustal stability are transformed into fuzzy information and then a model of fuzzy diagnosis is established. A fuzzy comprehensive evaluation of regional crustal stability in the Beijing region is made according to the seismic and geological conditions of the region. 展开更多
关键词 fuzzy mathematics regional stability BEIJING
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A data model for regions with indeterminate boundaries
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作者 NHAN Vu thi hong CHI Jeong hee RYU Keun ho 《重庆邮电学院学报(自然科学版)》 2004年第5期89-94,共6页
Most of spatial phenomena like natural vegetation units and land use areas constantly change over time and have uncertainty spatial extents. Till now, a considerable number of data models have been proposed for spatia... Most of spatial phenomena like natural vegetation units and land use areas constantly change over time and have uncertainty spatial extents. Till now, a considerable number of data models have been proposed for spatial objects with sharp boundaries as well as with indeterminate boundaries. However, they mainly concern space and time or space and fuzziness and not yet integrate them into a single unified framework. This paper introduces a formal definition of the conceptual fuzzy spatiotemporal data model, called FSTDM for fuzzy regions based on fuzzy set theory. We also contribute a method of manipulating queries with the presence of both temporal predicate and fuzzy spatial predicate in the condition clause efficiently. We then implement a prototype system. Through the experimental results, we prove that our work can be used to build a specialized system such as GIS, spatial database, and so on. 展开更多
关键词 数据模型 分界线 模糊区域 GIS 空间对象
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五螺旋框架下高校参与区域科技创新组态效应研究 被引量:1
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作者 尤莉 王瑞 《重庆高教研究》 北大核心 2024年第3期54-68,共15页
高校是推动区域科技创新和产业变革的关键力量,对区域科技创新系统具有支撑性和引领性。利用五螺旋创新理论框架,探究政府支持、产业基础、学术能力、公众需求、创新环境等关键要素影响高校参与区域科技创新的前因条件和交互效应。对比... 高校是推动区域科技创新和产业变革的关键力量,对区域科技创新系统具有支撑性和引领性。利用五螺旋创新理论框架,探究政府支持、产业基础、学术能力、公众需求、创新环境等关键要素影响高校参与区域科技创新的前因条件和交互效应。对比我国31个省份组态效应,结合NCA和fsQCA方法,发现高校参与区域科技创新具有“多重并发”特征。高校参与区域科技创新没有绝对最优路径,只有相对最优路径,不同驱动路径之间存在差异性和等效性。政府支持、产业基础、学术能力、公众需求、创新环境之间不同组态形成了3条高区域科技创新路径和4条非高区域科技创新路径。3条高区域科技创新路径分别是政产学公众联合导向型、政产公众环境联合导向型、产学公众环境联合导向型;4条非高区域科技创新路径分别是产业缺失型、政环境缺失型、政产环境缺失型、学术环境缺失型。其中,政府组织协调职能、持续稳定的公众参与机制和区域内部规模化创新环境有效促进了高校内部创新活动与区域整体要素资源的结构性契合,增加了不同驱动路径之间的等效转化机会。为此,不同区域应依据产业资源禀赋特点和高校发展特色,科学调整高校在区域科技创新系统的协同嵌入形式,从单一优化转向组态耦合,实现多重条件的组态优化。以新型举国体制为主线持续推动科教融汇、产教协同,激活公众创新基因和区域创新势能,不断提升高校参与区域科技创新的能力。 展开更多
关键词 区域科技创新 高校参与 五螺旋 模糊集定性比较分析
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贝叶斯优化模糊聚类地级行政区声环境
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作者 曾宇 姚琨 +1 位作者 任爽 户文成 《应用声学》 CSCD 北大核心 2024年第2期385-392,共8页
声环境功能区划是噪声污染管理的重要手段。当前声环境功能区划研究大多是基于某个特定的地级行政区来进行的,难以反映各地级行政区声环境的异同。该文基于134个地级行政区的人口、面积、各声环境功能区面积和及面积占比,进行地级行政... 声环境功能区划是噪声污染管理的重要手段。当前声环境功能区划研究大多是基于某个特定的地级行政区来进行的,难以反映各地级行政区声环境的异同。该文基于134个地级行政区的人口、面积、各声环境功能区面积和及面积占比,进行地级行政区声环境表征和归一化处理。以轮廓系数作为聚类有效性评价指标,基于贝叶斯优化模糊聚类方法对地级行政区声环境表征进行聚类分析。通过与谱聚类、K-medoids聚类、高斯混合模型聚类的聚类性能对比,验证了该方法的有效性。结果表明,我国地级行政区声环境分为9类,城市规模和用地情况发生显著变化导致其声环境表征和归类发生变化后应重新评估当前噪声污染管理政策,并借鉴同类的地级行政区的噪声污染管理政策做出必要的调整。 展开更多
关键词 声环境功能区 地级行政区 模糊聚类 贝叶斯优化 轮廓系数
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我国学前教育高质量发展的多组态路径——基于DPSIR框架的模糊集定性比较分析(fsQCA)
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作者 蔡文伯 龚杏玲 《教育与教学研究》 2024年第4期94-115,共22页
文章基于DPSIR框架设计评价指标体系对区域学前教育高质量发展水平进行评价,以熵权-TOPSIS计算指标权重和综合得分,结合模糊集定性比较分析(fsQCA)进行组态路径分析。研究发现:(1)我国学前教育高质量发展水平呈现由东向西递减的趋势,除... 文章基于DPSIR框架设计评价指标体系对区域学前教育高质量发展水平进行评价,以熵权-TOPSIS计算指标权重和综合得分,结合模糊集定性比较分析(fsQCA)进行组态路径分析。研究发现:(1)我国学前教育高质量发展水平呈现由东向西递减的趋势,除东部外,中部与西部区域学前教育高质量发展水平均值均低于全国均值;(2)基于DPSIR框架的区域学前教育发展系统驱动学前教育高质量发展具有“多重并发”与非对称性的特点;(3)存在两条高水平组态路径与3条非高水平组态路径,多条组态路径殊途同归,且高水平组态与非高水平组态处于非对称状态;(4)东部、中部与西部组态路径存在一定差异,三大区域学前教育高质量发展均离不开状态因子与响应因子的支持。为此,要完善机制体制建设,为学前教育发展提供保障;因地制宜制定发展策略,以协同路径驱动学前教育高质量发展;聚焦区域重点,以重点发展引领区域学前教育高质量发展。 展开更多
关键词 学前教育 高质量发展 DPSIR 模糊集定性比较分析(fsQCA) 区域差异 组态效应
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鲁南地区流体监测台网优化与监测效能评估
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作者 刘莉 王玲 +1 位作者 孔令爱 赵培 《四川地震》 2024年第1期30-34,共5页
结合鲁南地区地质构造背景,通过自主研发的高精度水位水温实时监测仪器,对地下流体监测站点软硬件设施进行升级改造,建设鲁南地区地下流体数字化监测台网。同时,构建基于层次分析法的鲁南地区地下流体监测效能评价体系,利用模糊综合评... 结合鲁南地区地质构造背景,通过自主研发的高精度水位水温实时监测仪器,对地下流体监测站点软硬件设施进行升级改造,建设鲁南地区地下流体数字化监测台网。同时,构建基于层次分析法的鲁南地区地下流体监测效能评价体系,利用模糊综合评价法对各观测站点进行量化的效能评估,为进一步提升该地区地下流体监测台网监测能力提供参考意见。 展开更多
关键词 鲁南地区 流体监测台网 效能评估 层次分析法 模糊综合评价法
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干旱半干旱区典型林分持水性能比较研究 被引量:2
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作者 韩青池 孙凯 +3 位作者 裴志永 陈宏伟 曹艳伟 孙小添 《水土保持研究》 CSCD 北大核心 2024年第3期239-246,共8页
[目的]水分供给是制约干旱及半干旱区发展的决定因素,科学评估干旱半干旱区典型林分的持水性能是规划防护林建设,调控林分结构与进行树种选择的重要依据。[方法]以库布齐沙漠鄂尔多斯造林总场内5种典型人工林为研究对象,利用野外收获法... [目的]水分供给是制约干旱及半干旱区发展的决定因素,科学评估干旱半干旱区典型林分的持水性能是规划防护林建设,调控林分结构与进行树种选择的重要依据。[方法]以库布齐沙漠鄂尔多斯造林总场内5种典型人工林为研究对象,利用野外收获法与室内浸水法分析林冠层、林下植被层、枯落物层及土壤层持水性能,引入模糊物元模型,结合欧式贴近度对不同林分持水性能进行定量评价。[结果](1)不同树种间林冠持水能力差异显著,表现为杨树旱柳混交林>榆树林>杨树林>沙柳林>樟子松林,林分持水量介于2.36~9.98 t/hm^(2)。(2)各林分林下植被的持水量介于0.84~3.66 t/hm^(2),生物量介于1.33~3.92 t/hm^(2),生物量表现出与持水量相同的变化趋势。(3)枯落物持水量介于1.96~29.25 t/hm^(2),生物量介于1.43~13.62 t/hm^(2),对数函数和幂函数可较好表现枯落物的动态持水量和动态吸水率。(4)各林分间土壤毛管持水量介于543.80~645.71 t/hm^(2),饱和持水量介于562.87~694.78 t/hm^(2),杨柳混交林土壤容重低于其他纯林,同时孔隙度比其他林分高。(5)欧式贴近度大小排序为杨柳混交林(0.805 6)>沙柳林(0.387 7)>榆树林(0.374 7)>杨树林(0.357 2)>樟子松林(0.163 2),欧式贴近度越大,林分持水性能越强,5种林型中杨柳混交林持水能力最强,樟子松林最差。[结论]建议未来经营干旱半干旱区人工防护林建设中,适当提高混交林比例,并尝试通过更多林分合理搭配进行防护林建设保护。 展开更多
关键词 干旱半干旱区 林分持水性能 模糊物元模型 欧式贴近度
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农村现代化区域差异AHP-Fuzzy综合评判 被引量:9
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作者 陈海燕 彭补拙 +1 位作者 朱振华 刘晶 《经济地理》 CSSCI 北大核心 1999年第6期27-31,共5页
根据系统分析原理,按照全面、可比、层次及可操作原则,建立了农村现代化指标体系。在确定农村现代化的层次结构基础上,首先采用层次分析法确定各指标的权重,其次运用模糊多级综合评判法对华东6 省1 市1996 年农村现代化水平... 根据系统分析原理,按照全面、可比、层次及可操作原则,建立了农村现代化指标体系。在确定农村现代化的层次结构基础上,首先采用层次分析法确定各指标的权重,其次运用模糊多级综合评判法对华东6 省1 市1996 年农村现代化水平进行了综合的评价,最后,阐述农村现代化区域差异产生的原因,扩大的机制和均衡发展的对策。 展开更多
关键词 农村现代化 AHP fuzzy 区域差异 中国
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区域旱灾风险评估与诊断的动态差异度系数模糊数随机模拟方法
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作者 赵齐雅 金菊良 +3 位作者 崔毅 汪洁 张诗琪 周乐 《灾害学》 CSCD 北大核心 2024年第1期195-201,共7页
为更准确、稳健地进行旱灾风险动态评估、关键障碍因子的定量识别,构建了差异度系数随评价指标样本值动态变化的三角模糊数与随机模拟耦合方法,并用于宿州市2007—2017年旱灾风险评估与诊断研究中,得到宿州市置信概率为95%的旱灾风险评... 为更准确、稳健地进行旱灾风险动态评估、关键障碍因子的定量识别,构建了差异度系数随评价指标样本值动态变化的三角模糊数与随机模拟耦合方法,并用于宿州市2007—2017年旱灾风险评估与诊断研究中,得到宿州市置信概率为95%的旱灾风险评价值区间,结果表明:旱灾风险评价结果呈“先增加,后减小,最后趋于稳定”的变化趋势,旱灾风险综合评价结果为“轻险”;危险性、暴露性、抗旱能力三个子系统是影响研究区域旱灾风险综合评价结果趋势变化的主因;耕地率、水库调蓄率、农业人口比例评价指标被诊断为中阻碍型因子,是需要重点调控的对象;置信概率区间增加了风险评价结果的可靠性信息,可反映受多种不确定影响因素综合作用下的实际旱灾风险情况,充分体现了联系数所表征的“不确定性”这一信息。 展开更多
关键词 区域 旱灾风险 评估与诊断 动态差异度系数 三角模糊数 随机模拟 安徽宿州
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基于群组决策的寒区隧道冻害风险评价研究
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作者 张亚琴 王道远 +5 位作者 袁金秀 张业权 赵斌 崔光耀 章浩天 孙梁 《铁道工程学报》 EI CSCD 北大核心 2024年第3期91-99,共9页
研究目的:为客观有效评估隧道冻害程度,基于群组决策和三角模糊数法构建寒区隧道冻害风险评价模型。首先,采用更有利于专家表达的三角模糊数建立判断矩阵,利用相容度指标确定专家判断水平,从而赋予相应权重;其次,综合考虑引起寒区隧道... 研究目的:为客观有效评估隧道冻害程度,基于群组决策和三角模糊数法构建寒区隧道冻害风险评价模型。首先,采用更有利于专家表达的三角模糊数建立判断矩阵,利用相容度指标确定专家判断水平,从而赋予相应权重;其次,综合考虑引起寒区隧道冻害的温度、水文、围岩条件和工程措施等因素,形成二级评价指标,通过三角模糊数群组决策模型确定各指标权重;再次,将二级评价指标分为10个定量指标和6个定性指标,定量指标按梯形分布建立隶属度函数,定性指标由专家按百分制打分,再按梯形分布函数确定各等级隶属度;最后,通过模糊综合评价方法计算确定隧道冻害等级,并提供相应的预防措施。研究结论:(1)选取温度、水文、围岩条件和工程措施4个一级指标、16个二级指标,设置4个冻害等级,构建了基于三角模糊数的群组决策寒区隧道冻害风险综合评价体系;(2)本文提出的冻害风险评价模型应用于杀虎口隧道,风险等级评价结果与隧道实际冻害一致,验证了模型的合理性;(3)本文模型更加客观全面,可为隧道冻害风险提供安全预警和防控建议。 展开更多
关键词 寒区隧道 三角模糊数 群组决策 冻害风险 综合评价
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区域投资环境评价的Fuzzy群体多准则决策方法 被引量:4
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作者 吴小月 王坚强 《系统工程》 CSCD 北大核心 2008年第3期86-90,共5页
区域投资环境评价是一种信息不完全确定的多准则决策问题。针对这类问题,利用传统TOPSIS方法的基本思路,提出了一种信息不完全确定的Fuzzy群体多准则决策方法。在该方法中,首先对每一决策者,利用TOPSIS方法进行方案的准则集成,求解多目... 区域投资环境评价是一种信息不完全确定的多准则决策问题。针对这类问题,利用传统TOPSIS方法的基本思路,提出了一种信息不完全确定的Fuzzy群体多准则决策方法。在该方法中,首先对每一决策者,利用TOPSIS方法进行方案的准则集成,求解多目标优化模型得到各准则的权系数,并计算方案的准则集成值;然后进行方案的群体集成,通过求解线性规划模型得到决策者的权重,进而得到方案集的整体排序。最后用实例验证了方法的可行性和有效性。 展开更多
关键词 区域投资环境 信息不完全 fuzzy群体多准则决策 模糊数 TOPSIS方法
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