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第一书记来了 梨树村变了
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作者 高艳红 《新长征》 2019年第4期29-30,共2页
在距延吉市区约70公里的三道湾镇梨树村,村民们谈起驻村第一书记刘永时,总有说不完的话、道不完的情,言语间透着的都是感激,脸上带着的是质朴的笑容。人们都说:'第一书记来了,梨树村真的变了。'让基础设施先行'脱贫'201... 在距延吉市区约70公里的三道湾镇梨树村,村民们谈起驻村第一书记刘永时,总有说不完的话、道不完的情,言语间透着的都是感激,脸上带着的是质朴的笑容。人们都说:'第一书记来了,梨树村真的变了。'让基础设施先行'脱贫'2018年1月,延边州教育局干部刘永到三道湾镇梨树村担任第一书记兼驻村工作队队长,开展脱贫攻坚工作。 展开更多
关键词 梨树 驻村 延边州 村民 区约 质朴 三道湾
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Soil Nutrients in Intensive Agricultural Areas with Different Land-Use Types in Qingzhou County, China 被引量:9
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作者 ZHAO Geng-Xing LI Xiu- Juan +2 位作者 WANG Ri-Yan LI Tao YUE Yu-De 《Pedosphere》 SCIE CAS CSCD 2007年第2期165-171,共7页
On the basis of the data obtained from a field survey, the relationship between land use and soil nutrients was evaluated in Qingzhou County, Shandong Province, China, through a statistical analysis of differences in ... On the basis of the data obtained from a field survey, the relationship between land use and soil nutrients was evaluated in Qingzhou County, Shandong Province, China, through a statistical analysis of differences in 17 nutrients in five types of cultivated land. The results showed significant effects (P < 0.05 or P < 0.01) of land-use type on soil organic matter and concentration of macronutrients, secondary nutrients, and micronutrients, as well as total salt and soil pH. In vegetable land, because of the large amounts of fertilizer applied to vegetable crops, the concentrations of most soil nutrients, with exception of available Si and micronutrients, were higher than those in grain cropland. Grain cropland had a significantly lower total salt content (P < 0.01) and tended to have a higher soil pH than vegetable land. Within subtypes of land use, dry land, irrigable land, and open-air vegetable land had the highest coefficient of variation (CV) for available P, whereas protected vegetable land had the highest CV for total N and available S. In general, land-use types had greater impact on macronutrients than on secondary nutrients and micronutrients. 展开更多
关键词 cultivated land land-use type Qingzhou County soil nutrients
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Spacecraft Attitude Control with Saturation and Attitude Forbidden Constraints via Second⁃Order Cone Programming
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作者 CHEN Xi CAO Ruihao HU Qinglei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第2期237-248,共12页
This paper investigates the optimal control problem of spacecraft reorientation subject to attitude forbidden constraints,angular velocity saturation and actuator saturation simultaneously.A second-order cone programm... This paper investigates the optimal control problem of spacecraft reorientation subject to attitude forbidden constraints,angular velocity saturation and actuator saturation simultaneously.A second-order cone programming(SOCP)technology is developed to solve the strong nonlinear and non-convex control problem in real time.Specifically,the nonlinear attitude kinematic and dynamic are transformed and relaxed to a standard affine system,and linearization and L1 penalty technique are adopted to convexify non-convex inequality constraints.With the proposed quadratic performance index of angular velocity,the optimal control solution is obtained with high accuracy using the successive SOCP algorithm.Finally,the effectiveness of the algorithm is validated by numerical simulation. 展开更多
关键词 spacecraft reorientation attitude forbidden constraints actuator saturation velocity saturation secondorder cone programming(SOCP)
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Matrix-bound phosphine in Ny-Alesund Area of Arctic
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作者 封颖 Wang Qiang +1 位作者 Yao Ziwei Geng Jinju 《High Technology Letters》 EI CAS 2009年第3期331-336,共6页
Phosphine, a ubiquitous trace gas in the atmosphere, acts as a carrier of gasous phosphorus in the biogeochemical cycle. The research of phosphine will show new light on the mechanisms of how the phos- phorus suppleme... Phosphine, a ubiquitous trace gas in the atmosphere, acts as a carrier of gasous phosphorus in the biogeochemical cycle. The research of phosphine will show new light on the mechanisms of how the phos- phorus supplement influence the biogeochemical cycle and global wanning. In this paper, we detect the phosphine in Arctic Pole area for the first time. The result shows that matrix-bound phosphine(MBP) ex- ists in all the samplings. Phosphine distributions varied with different environmental origins. Average phosphine concentrations in tundra soil, lake sediments, sea sediments, seabird-droppings and deer guanos were 14.17ng/kg dry, 35.44 kg dry, 67.20 kg dry, 32.9 ng/kg dry, and 25.52 ng/kg dry re- spectively. Correlation analysis shows that there is an obviously positive correlation between Porg and MBP. It could be concluded that anaerobic decomposition of Porg and the mechano-chemistry action of the rock probably are the possible reasons explaining the mechanism of MBP production in Arctic Pole area. 展开更多
关键词 matrix-bound phosphine (MBP) Arctic Pole area distribution Porg rock
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Recognition and depiction of special geologic bodies of Member 3 of Dongying Formation in Littoral Slope Zone,Qikou Sag 被引量:4
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作者 陈思 王华 +6 位作者 周立宏 黄传炎 任培罡 王家豪 廖远涛 向雪梅 夏存银 《Journal of Central South University》 SCIE EI CAS 2011年第3期898-908,共11页
The purpose of this study is to forecast the profitable oil and gas reservoir,which is the key of finding hydrocarbon,based on the conception of special geologic bodies.With the guiding methodology of the research thi... The purpose of this study is to forecast the profitable oil and gas reservoir,which is the key of finding hydrocarbon,based on the conception of special geologic bodies.With the guiding methodology of the research thinking of integration of point-line-surface by using the methods and techniques of logging,seismic,seismic attribute,and logging constrained inversion in 3D data volume,the special geologic bodies of Member 3 of Dongying Formation in Littoral Slope Zone of Qikou Sag,which has important hydrocarbon exploration potential,are recognized and described under the constraint of sequence stratigraphic framework.As a result,the developed scale,geometric shape and space distribution feature of the special geologic bodies are forecasted;the inner structure and sequence structure patterns of the geologic bodies are also ascertained.From the lowstand system tract (LST) and lacustrine expanding system tract (EST) to the highstand system tract (HST),the geologic bodies have evolved from relative centralization of lake basin reducing period to three relative dispersive isolated parts of broad lake basin period.According to the relevance and regularity of the development of geologic bodies,the conclusions can be obtained that three types of potential profitable reservoir traps,including the lithologic lens traps,lithologic updip pinchout traps and structural-lithologic composite traps,are forecasted.In addition,scientific basis for further hydrocarbon exploration in new area (few-well area and no-well area) is offered in the guidance of sequence stratigraphic model. 展开更多
关键词 Qikou Sag Littoral Slope Zone Dongying Formation special geologic bodies
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Assessment of Industrial Land Use Intensity: A Case Study of Beijing Economic-technological Development Area 被引量:3
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作者 HUANG Daquan WAN Wei +1 位作者 DAI Teqi LIANG Jinshe 《Chinese Geographical Science》 SCIE CSCD 2011年第2期222-229,共8页
In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity ... In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity of land use needs to be evaluated. The current method of comprehensive evaluation and grading by one index system has the limitations due to the existence of differences between regions and industries. This paper evaluates industrial land use intensity by Total Factor Productivity (TFP) analysis, which not only measures the intensity but also illustrates the ef-ficiency of input factors. This method is applied to the Beijing Economic-technological Development Area (BDA). A comparison analysis on factor use efficiency and input structure of capital and labor between industries is also carried out in the absence of a labor-income ratio. 展开更多
关键词 land use intensity industrial land use Total Factor Productivity (TFP) Beijing Economic-technological Development Area (BDA)
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Buffer Sizing Method for Constructing Stable Schedules with Duration Constraints
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作者 Piotr Jaskowski Slawomir Biruk 《Journal of Civil Engineering and Architecture》 2010年第10期24-30,共7页
The assumption of static and deterministic conditions is common in the practice of construction project planning. However, at the construction phase, projects are subject to uncertainty. This may lead to serious sched... The assumption of static and deterministic conditions is common in the practice of construction project planning. However, at the construction phase, projects are subject to uncertainty. This may lead to serious schedule disruptions and, as a consequence, serious revisions oft.he schedule baseline. The aim of the paper is developing a method for constructing robust project schedules with a proactive procedure. Robust project scheduling allows for constructing stable schedules with time buffers introduced to cope with multiple disruptions during project execution. The method proposed by the authors, based on Monte Carlo simulation technique and mathematical programming for buffer sizing optimization, was applied to scheduling an example project. The results were compared, in terms of schedule stability, to those of the float factor heuristic procedttre. 展开更多
关键词 Construction project scheduling stable solution robust schedule BUFFERING risk management
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Informal Settlements: A Shape Grammar Approach 被引量:1
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作者 Maria Angela Dias 《Journal of Civil Engineering and Architecture》 2014年第11期1389-1395,共7页
Informal urban development is seldomly covered in academic studies or professional architectural training. This article sets forth the first stage of a novel study that observes the informal city using the methodology... Informal urban development is seldomly covered in academic studies or professional architectural training. This article sets forth the first stage of a novel study that observes the informal city using the methodology of analysis of architecture called shape grammars. The idea is to recognize peculiarities in the occupation of the land and the volumetric features of the buildings. Rocinha favela, in Rio de Janeiro, Brazil, is taken as a case study with the primary aim of extrapolating a set of rules for its morphological features so that these rules can be used to generate new shapes, whilst bearing in mind the issues of adaptation and transformation which are so characteristic of informal settlements. There is some expectation that this study may help improve the housing and public space in the favela and enable new housing programs to observe the way the buildings and different architectural elements combined, forming a new channel of interchange with the spatial organization of the favela. 展开更多
关键词 Shape grammar analysis of the form informal architecture.
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Favela’s Houses as Design Reference: Using Shape Grammar 被引量:1
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作者 Margaret Lica Chokyu Maria Angela Dias 《Journal of Civil Engineering and Architecture》 2018年第7期483-492,共10页
Shape grammar has been used by many researchers to identify and/or define languages in architectural design. This paper presents a methodology developed using shape grammar to analyze the informal city, specifically F... Shape grammar has been used by many researchers to identify and/or define languages in architectural design. This paper presents a methodology developed using shape grammar to analyze the informal city, specifically Favela da Rocinha’s buildings, in Rio de Janeiro. The goal was finding the organizational foundations of self-built houses in an informal settlement. A methodology was developed to find composition patterns and to infer a set of rules which defines a shape grammar of Rocinha houses, allowing synthesis and analysis of low cost solutions for house designs. And above all, it highlights underlying design solutions produced empirically by inhabitants of favelas, emphasizing the diversity in favela’s architecture, and, that is also able to reflect the particular necessities of targeted population. 展开更多
关键词 Shape grammar shape analysis informal architecture favela.
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Conserving Agricultural Heritage Systems through Tourism: Exploration of Two Mountainous Communities in China 被引量:11
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作者 SUN Ye-hong Mary Jane DELA CRUZ +2 位作者 MIN Qing-wen LIU Mou-cheng ZHANG Ling-yun 《Journal of Mountain Science》 SCIE CSCD 2013年第6期962-975,共14页
Community plays an important role in the preservation of agricultural heritage system (AHS). Recently, many AHS have been valorized as interesting resources for rural tourism. The expectations are that tourism devel... Community plays an important role in the preservation of agricultural heritage system (AHS). Recently, many AHS have been valorized as interesting resources for rural tourism. The expectations are that tourism development (TD) can be supportive for the conservation of AHS while creating benefits for local communities. In this study, two mountainous pilot villages (Longxian and Xiaohuang) in a global conservation project for traditional agricutural systems - Globally Important Agricultural Heritage Systems (GIAHS) were selected to identify the relationship between AHS conservation and TD. The study undertook in-depth interviews, and questionnaires of village residents and informal discussions with local villagers. A t-test and a linear regression model were implemented to explore the comparative dimensions of the two communities with different geographical location, economic situation, and stage of TD. The research found some similarities and differences in the two mountainous communities during AHS conservation and TD. Firstly, AHS are preservaed well in both villages unconsiously, while the residents in Xiaohuang value more highly the heritage elements than the respondents in Longxian, and the villagers in Xiaohuang are more worried about their heritage system; Secondly, both villages expect lots of benefits from TD and they clearly perceive more positive than negative impact from tourism and thus approve TD, while the hugedifferent perception on transportation and accessibility in the two villages reflects the bottleneck of TD in Xiaohuang village. At the same time, the respondents from Xiaohuang perceive more positive and fewer negative impact from tourism than the respondents from Longxian. Thirdly, the respondents in the two villages all show positive attitudes towards participation in tourism mostly motivated by the high income expectation. The main factors to determine the community perception in two villages were also analyzed based on the data process. A location-based coneeputal framework of AHS conservation in partnership with TD at community scale is proposed at the end of the paper. The dynamics of tourism development, that could enhance a better understanding of the complex relationship between conservation objectives and tourism development are discussed. 展开更多
关键词 Agricultural heritage system Tourismdevelopment Mountainous communities ZhejiangProvince Guizhou Province China
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The Diseases of Coffee under the Changing Climate: The Established Situation in Kenya
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作者 Harrison M. Mugo Lucy W. Irungu Paul N. Ndegwa 《Journal of Agricultural Science and Technology(A)》 2012年第2期265-272,共8页
The distribution of key diseases of coffee particularly the Coffee berry disease (CBD) and Coffee leaf rust (CLR) in Kenya depended on coffee growing agro-ecological zones, which have varied climatic conditions. U... The distribution of key diseases of coffee particularly the Coffee berry disease (CBD) and Coffee leaf rust (CLR) in Kenya depended on coffee growing agro-ecological zones, which have varied climatic conditions. Under the changing climate, there has been an observed shift in their altitudinal distribution. To ascertain whether these diseases have shifted in their distribution, an extensive field survey covering 120 coffee farmers/households in all the coffee growing agro ecological zones was conducted. The survey established four coffee diseases; -viz. Coffee berry disease, Coffee leaf rust, Fusarium root disease (FRD) and Bacterial blight of coffee (BBC) as of economic importance to the farming community. The CBD, CLR and FRD were widely distributed in all coffee growing agro ecological zones. Of the four diseases, the CBD (65%) and CLR (63.3%) were most common as reported by the farmers, however these diseases dominated in their respective agro ecological zones; CBD (72.2%) in Upper Midland 1 (UM1) and CLR (75.0%) in Upper Midland 2 (UM2). Both diseases equally infected coffee farms (69.2%) in main coffee zone (UM2). According to the survey said diseases have increased their altitudinal range, a trend that will increase diseases pressure in coffee growing areas. 展开更多
关键词 Coffee berry disease coffee leaf rust climate change agro-ecological zones altitudinal range.
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Assessment of Wind Characteristics and Wind Potential Energy Yield in the Jordanian Southern Region
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作者 Mohammed Sulaiman Al-Soud 《Journal of Energy and Power Engineering》 2015年第4期348-357,共10页
This study presents investigation and assessment of wind characteristics and wind energy potential for four sites at the Jordanian southern region (Hareer, Ma'an, Aqaba and Fujaij). Based on the available measured ... This study presents investigation and assessment of wind characteristics and wind energy potential for four sites at the Jordanian southern region (Hareer, Ma'an, Aqaba and Fujaij). Based on the available measured data sources, the data were analyzed using hourly and mean monthly WS (wind speed) data at different heights, using a two-parameter probability distribution of Weibull function. The recognized monthly and yearly Weibull functions were considered for the second analysis step. The wind potential energy yields assessment for an ideal capable wind turbine was implemented. Finally, for energy yield estimation, a wind turbine from Vestas with a 660 kW rated power was chosen. The wind turbine characteristics: AF (availability factor), CF (capacity factor) and wind turbine efficiency (η), were defined and calculated for each site. The result of the analysis showed that, all sites have good wind energy potential, the Hareer site at Tafila has the best wind resources. 展开更多
关键词 Wind energy Weibull distribution PROBABILITY availability factor.
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Integrated assessment model of water resources constraint intensity on urbanization in arid area 被引量:5
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作者 鲍超 方创琳 《Journal of Geographical Sciences》 SCIE CSCD 2009年第3期273-286,共14页
Water has become a key restricting factor of the urbanization process in developing arid areas.Based on qualitative and quantitative methods,we constructed an integrated in-dicator system to assess the status of water... Water has become a key restricting factor of the urbanization process in developing arid areas.Based on qualitative and quantitative methods,we constructed an integrated in-dicator system to assess the status of water resources and urbanization system in arid area,and established an AHP model reformed by entropy technology to evaluate the temporal and spatial variations of water resources constraint intensity on urbanization.This model is ap-plied to the Hexi Corridor,a typical arid area in NW China.Results show that,water resources constraint intensity on urbanization in the Hexi Corridor is bigger in the east and smaller in the west.It has changed from the less strong constraint type into the strong constraint type from 1985 to 2005,yet it decreased appreciably in recent years.At present,most areas in the Hexi Corridor belong to the less strong or strong constraint type.Through rational adjustment of water resources and urbanization system,the Hexi Corridor can still promote water resources sustainable utilization and accelerate the urbanization process.This study suggests that the integrated assessment model of water resources constraint intensity on urbanization is an effective method to analyze the conflicts between water resources and urbanization system in arid area. 展开更多
关键词 water resources constraint intensity (WRCI) URBANIZATION AHP model temporal and spatial variation Hexi Corridor
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Comparison between several seismic inversion methods and their application in mountainous coal fields of western China 被引量:9
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作者 XU Yongzhong CHEN Tongjun +2 位作者 CHEN Shizhong HUANG Weichuan WU Gang 《Mining Science and Technology》 EI CAS 2010年第4期585-590,共6页
With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploratio... With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploration of coal fields. First, we introduce principles and features of three kinds of inversion methods. i.e., Model-Based Inversion, Constrained Sparse Spike Inversion (CSSI) and Geology-Seismic Feature Inversion. Secondly, these inversion methods are contrasted in their application to 3D seismic data from some coalfields in western China. The main information provided by the research includes: improving the vertical resolution of coal deposit strata, inferring lateral variation of the lithology and predicting coal seams and their roof lithology. Finally, the comparison between the three methods shows that the model-based inversion has the higher resolution, while CSSI inversion has better waveform continuity. The geology-seismic feature inversion requires information from a large number of wells and many types of logging curves of good quality. All three methods can meet the requirements of seismic exploration for lithological exploration in coal fields. 展开更多
关键词 model-based inversion constrained sparse spike inversion geology-seismic feature inversion coal seam lithological exploration
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Current Status, Challenges and Policy Recommendations Regarding the Sustainable Development of Mining Areas in China 被引量:3
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作者 李倩 张文忠 王岱 《Journal of Resources and Ecology》 CSCD 2014年第1期42-52,共11页
As important suppliers of energy resources, mining areas have made huge contributions to China’s socio-economic development. However, some factors are inhibiting the further development of mining areas and, thereby p... As important suppliers of energy resources, mining areas have made huge contributions to China’s socio-economic development. However, some factors are inhibiting the further development of mining areas and, thereby pose a threat to social stability, as wel as resource and energy security in the country. In 2012, the National Development and Reform Commission formulated a project aiming to support the sustainable development of mining areas. This study collected and compiled the project’s first-hand survey data from 128 mining areas across China and comprehensively investigated the current development status of the country’s mining areas. The problems facing the development of China’s mining areas are analyzed, and four speciifc suggestions are provided, namely:promote industry transformation, remove institutional constraints, improve people’s livelihoods to maintain the stability of mining areas, and protect the environment to provide a clean, healthy living environment for mining area residents. This paper provides the ifrst comprehensive and systematic picture of China’s mining areas and highlights the importance of mining areas for the country’s economic and social development. 展开更多
关键词 mining areas status evaluation limiting factors policy suggestions
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Evolution Characteristics of Urban Land Use Efficiency under Environmental Constraints in China 被引量:6
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作者 SHI Jiaying HE Yafen 《Journal of Resources and Ecology》 CSCD 2021年第2期143-154,共12页
In the context of high-quality economic development and coordinated regional development,this paper measures the urban land use efficiency of 275 prefecture-level cities in China from 2003 to 2016,taking into account ... In the context of high-quality economic development and coordinated regional development,this paper measures the urban land use efficiency of 275 prefecture-level cities in China from 2003 to 2016,taking into account the unexpected output(environmental pollution),and explores the temporal and spatial evolution of urban land use efficiency through kernel density estimation and spatial autocorrelation analysis.The results show that:(1)From 2003 to 2016,China’s urban land use efficiency showed an overall fluctuating growth,but it remained at a low level.The mean value of urban land use efficiency has been gradually decreasing in east,west and central regions.(2)In the whole country and the eastern,central and western regions,the regional differences have been increasing,and the efficiency values of the whole country and the east have become polarized.(3)Urban land use efficiency shows a weak spatial positive correlation,but the degree of spatial agglomeration is increasing.High-high agglomeration areas are mostly distributed in the southeastern coastal areas,and extend into the central region,while most of the high-low polarized areas are the capital cities of the central and western regions.The low-high depressed areas are scattered around the high-value accumulation areas,some of which have turned into high-high agglomeration areas during the study period,while the low-low homogeneous areas are mainly distributed in the central,western and northeastern regions.Therefore,it is proposed that strengthening the utilization of urban stock land,strengthening the regional cooperation mechanism,and formulating policies which improve the efficiency of land use are effective ways to promote the intensive and economical use of urban land,as well as regional coordinated development. 展开更多
关键词 urban land use efficiency regional coordinated development environmental constraints SBM-undesirable model spatiotemporal evolution
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Remote sensing-based artificial surface cover classification in Asia and spatial pattern analysis 被引量:13
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作者 KUANG WenHui CHEN LiJun +6 位作者 LIU JiYuan XIANG WeiNing CHI WenFeng LU DengSheng YANG TianRong PAN Tao LIU AiLin 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第9期1720-1737,共18页
Artificial surfaces, characterized with intensive land-use changes and complex landscape structures, are important indicators of human impacts on terrestrial ecosystems. Without high-resolution land-cover data at cont... Artificial surfaces, characterized with intensive land-use changes and complex landscape structures, are important indicators of human impacts on terrestrial ecosystems. Without high-resolution land-cover data at continental scale, it is hard to evaluate the impacts of urbanization on regional climate, ecosystem processes and global environment. This study constructed a hierarchical classification system for artificial surfaces, promoted a remote sensing method to retrieve subpixel components of artificial surfaces from 30-m resolution satellite imageries(Globe Land30) and developed a series of data products of high-precision urban built-up areas including impervious surface and vegetation cover in Asia in 2010. Our assessment, based on multisource data and expert knowledge, showed that the overall accuracy of classification was 90.79%. The mean relative error for the impervious surface components of cities was 0.87. The local error of the extracted information was closely related to the heterogeneity of urban buildings and vegetation in different climate zones. According to our results, the urban built-up area was 18.18×104 km2, accounting for 0.59% of the total land surface areas in Asia; urban impervious surfaces were 11.65×104 km2, accounting for 64.09% of the total urban built-up area in Asia. Vegetation and bare soils accounted for 34.56% of the urban built-up areas. There were three gradients: a concentrated distribution, a scattered distribution and an indeterminate distribution from east to west in terms of spatial pattern of urban impervious surfaces. China, India and Japan ranked as the top three countries with the largest impervious surface areas, which respectively accounted for 32.77%, 16.10% and 11.93% of the urban impervious surface area of Asia. We found the proportions of impervious surface and vegetation cover within urban built-up areas were closely related to the economic development degree of the country and regional climate environment. Built-up areas in developed countries had relatively low impervious surface and high public green vegetation cover, with 50–60% urban impervious surfaces in Japan, South Korea and Singapore. In comparison, the proportion of urban impervious surfaces in developing countries is approaching or exceeding 80% in Asia. In general, the composition and spatial patterns of built-up areas reflected population aggregation and economic development level as well as their impacts on the health of the environment in the sub-watershed. 展开更多
关键词 Artificial surface cover CITY Impervious surface Vegetation cover Remote sensing classification ASIA
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The Institutional Supply of China's Participation in the International Monetary System Reform 被引量:2
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作者 Yonghui Wang 《Fudan Journal of the Humanities and Social Sciences》 2014年第2期287-305,共19页
There exist dual features of internationalization and regionalization in the current international monetary system, and the U.S. dollar is still in a dominant position in the system. A lack of relevant institutional c... There exist dual features of internationalization and regionalization in the current international monetary system, and the U.S. dollar is still in a dominant position in the system. A lack of relevant institutional constraints has led to institutional deficiencies and systematic risks in the international monetary system, and resulted in the frequent financial crises in the world in recent years. As an emerging economy closely related to the current international monetary system, China has responsibilities and obligations to participate actively in international monetary system reform and push forward international monetary system reform through institutional supply. 展开更多
关键词 China International monetary system Institutional innovation Institutional supply
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Community Detection with the Weighted Parsimony Criterion
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作者 BETTINELLI Andrea HANSEN Pierre LIBERTI Leo 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第3期517-545,共29页
Community detection in networks has been studied extensively in the last decade. Many criteria, expressing the quality of the partitions obtained, as well as a few exact algorithms and a large number of heuristics hav... Community detection in networks has been studied extensively in the last decade. Many criteria, expressing the quality of the partitions obtained, as well as a few exact algorithms and a large number of heuristics have been proposed. The parsimony criterion consists in minimizing the number of edges added or removed from the given network in order to transform it into a set of disjoint cliques.Recently Zhang, Qiu and Zhang have proposed a weighted parsimony model in which a weight coefficient is introduced to balance the numbers of inserted and deleted edges. These authors propose rules to select a good value of the coefficient, use simulated annealing to find optimal or near-optimal solutions and solve a series of real and artificial instances. In the present paper, an algorithm is proposed for solving exactly the weighted parsimony problem for all values of the parameter. This algorithm is based on iteratively solving the problem for a set of given values of the parameter using a row generation algorithm. This procedure is combined with a search procedure to find all lowest breakpoints of the value curve(i.e., the weighted sum of inserted and deleted edges). Computational results on a series of artificial and real world networks from the literature are reported. It appears that several partitions for the same network may be informative and that the set of solutions usually contains at least one intuitively appealing partition. 展开更多
关键词 Community detection complex networks parsimony.
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Attribute reduction in interval-valued information systems based on information entropies 被引量:9
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作者 Jian-hua DAI Hu HU +3 位作者 Guo-jie ZHENG Qing-hua HU Hui-feng HAN Hong SHI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第9期919-928,共10页
Interval-valued data appear as a way to represent the uncertainty affecting the observed values. Dealing with interval-valued information systems is helpful to generalize the applications of rough set theory. Attribut... Interval-valued data appear as a way to represent the uncertainty affecting the observed values. Dealing with interval-valued information systems is helpful to generalize the applications of rough set theory. Attribute reduction is a key issue in analysis of interval-valued data. Existing attribute reduction methods for single-valued data are unsuitable for interval-valued data. So far, there have been few studies on attribute reduction methods for interval-valued data. In this paper, we propose a framework for attribute reduction in interval-valued data from the viewpoint of information theory. Some information theory concepts, including entropy, conditional entropy, and joint entropy, are given in interval-valued information systems. Based on these concepts, we provide an information theory view for attribute reduction in interval-valued information systems. Consequently, attribute reduction algorithms are proposed. Experiments show that the proposed framework is effective for attribute reduction in interval-valued information systems. 展开更多
关键词 Rough set theory Interval-valued data Attribute reduction Entropy
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