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空间、时间、技术三位一体的教学实践探索——基于美国密西根大学的教学观察 被引量:5
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作者 胡晓红 李美希 《教育理论与实践》 CSSCI 北大核心 2018年第30期38-40,共3页
教学环境是教学实践的重要载体,教学实践的有效开展不仅仅需要教师深厚的理论底蕴和教学方法的创新,更需要优良教学环境的支持。对于教学而言,灵活多变和多样化的教学环境将会赋予教学以想象力和创新力,进而创造出良好的教学效果。密西... 教学环境是教学实践的重要载体,教学实践的有效开展不仅仅需要教师深厚的理论底蕴和教学方法的创新,更需要优良教学环境的支持。对于教学而言,灵活多变和多样化的教学环境将会赋予教学以想象力和创新力,进而创造出良好的教学效果。密西根大学创造出独特的教学环境,突出表现为以教师空间和桌椅设计为特色的空间环境、灵活多样的教学时间环境以及以网络多媒体为代表的技术环境,体现的是以学生为中心、尽一切可能激发学生自主探索未知世界的求知欲的教学理念。 展开更多
关键词 空间、时间与技术三位一体教学 教学环境 教学实践 密西根大学 多样空间 多元化时间 多维的技术教学
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列斐伏尔《节奏分析:空间、时间和日常生活》一书的结构 被引量:1
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作者 关巍 张晓娜 《濮阳职业技术学院学报》 2016年第5期7-10,共4页
《节奏分析:空间、时间和日常生活》是法国哲学家列斐伏尔思考资本主义条件下异化问题的核心著作,这部著作构建了一个有关节奏化与异化的哲学体系。该著作七大章节之间具有深层次的逻辑关系,其中,节奏化即异化是该书作出的基本判断,&qu... 《节奏分析:空间、时间和日常生活》是法国哲学家列斐伏尔思考资本主义条件下异化问题的核心著作,这部著作构建了一个有关节奏化与异化的哲学体系。该著作七大章节之间具有深层次的逻辑关系,其中,节奏化即异化是该书作出的基本判断,"节奏分析"和"身体"是其基本的建构主线。 展开更多
关键词 列斐伏尔 《节奏分析:空间、时间和日常生活》 异化
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希格弗莱德·吉迪恩与《空间、时间与建筑》第一版解读
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作者 闵晶 《建筑师》 CSSCI 2023年第4期109-120,共12页
作为现代建筑历史的经典著作,希格弗莱德·吉迪恩的《空间、时间与建筑:一种新传统的成长》在推动现代运动中扮演了关键的角色。尽管这本书的第一版出版于1941年,但它在帮助我们理解现代建筑方面起着非常重要的作用,为现代建筑提供... 作为现代建筑历史的经典著作,希格弗莱德·吉迪恩的《空间、时间与建筑:一种新传统的成长》在推动现代运动中扮演了关键的角色。尽管这本书的第一版出版于1941年,但它在帮助我们理解现代建筑方面起着非常重要的作用,为现代建筑提供了理论基础。本文将通过《空间、时间与建筑》第一版来分析吉迪恩对现代建筑的史学建构。 展开更多
关键词 希格弗莱德·吉迪恩 空间、时间与建筑》 现代建筑 史学
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图文之间:《空间、时间与建筑》的视觉策略 被引量:1
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作者 闵晶 《建筑学报》 CSSCI 北大核心 2023年第3期108-116,共9页
希格弗莱德·吉迪恩的《空间、时间与建筑:一种新传统的成长》作为一本现代建筑历史的经典之作,为现代建筑建立了宏大的史学。分析了这本书的成功不仅在于它的历史叙事质量,还在于视觉品质与文本论述的相辅相成,其中,视觉策略在书... 希格弗莱德·吉迪恩的《空间、时间与建筑:一种新传统的成长》作为一本现代建筑历史的经典之作,为现代建筑建立了宏大的史学。分析了这本书的成功不仅在于它的历史叙事质量,还在于视觉品质与文本论述的相辅相成,其中,视觉策略在书中起了至关重要的作用。 展开更多
关键词 希格弗莱德·吉迪恩 空间、时间与建筑》 视觉策略
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群体突发异常事件检测与事件源定位算法 被引量:3
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作者 李海丰 姜子政 +1 位作者 范龙飞 陈新伟 《中国民航大学学报》 CAS 2019年第3期49-53,64,共6页
提出一种群体突发异常事件检测与事件源定位算法以提高检测的准确性。算法分为群体异常行为检测和事件源定位两个阶段,在异常行为检测阶段,提出一种空间、时间联合的异常行为检测算法:在空间角度,提取平均动能分布直方图来描述人群的运... 提出一种群体突发异常事件检测与事件源定位算法以提高检测的准确性。算法分为群体异常行为检测和事件源定位两个阶段,在异常行为检测阶段,提出一种空间、时间联合的异常行为检测算法:在空间角度,提取平均动能分布直方图来描述人群的运动特征,并使用支持向量机分类器对不同状态的人群运动特征进行分类;在时间角度,构建隐马尔可夫模型,对场景中连续的人群行为状态进行异常检测。在事件源定位阶段,在随机抽样一致性算法框架下通过计算异常行为人群的反向延长线交点,实现了事件源位置的定位,并可同时标记多个事件源位置。在UMN公共数据集上进行实验,并与传统光流法、SIFT点检测法与社会力法进行对比,结果表明,该算法能够有效检测出群体异常行为,且AUC=0.967,比上述3种方法的AUC分别提高0.127、0.074、0.007,并成功标记出事件源的合理位置。 展开更多
关键词 群体异常事件检测 事件源定位 空间、时间联合 随机抽样一致性
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High angle prestack depth migration with absorption compensation 被引量:1
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作者 周辉 林鹤 +1 位作者 盛善波 王颖 《Applied Geophysics》 SCIE CSCD 2012年第3期293-300,360,361,共10页
The absorption effect of actual subsurface media can weaken wavefield energy, decrease the dominating frequency, and further lead to reduced resolution. In migration, some actions can be taken to compensate for the ab... The absorption effect of actual subsurface media can weaken wavefield energy, decrease the dominating frequency, and further lead to reduced resolution. In migration, some actions can be taken to compensate for the absorption effect and enhance the resolution. In this paper, we derive a one-way wave equation with an attenuation term based on the time- space domain high angle one-way wave equation. A complicated geological model is then designed and synthetic shot gathers are simulated with acoustic wave equations without and with an absorbing term. The derived one-way wave equation is applied to the migration of the synthetic gathers without and with attenuation compensation for the simulated shot gathers. Three migration profiles are obtained. The first and second profiles are from the shot gathers without and with attenuation using the migration method without compensation, the third one is from the shot gathers with attenuation using the migration method with compensation. The first and third profiles are almost the same, and the second profile is different from the others below the absorptive layers. The amplitudes of the interfaces below the absorptive layers are weak because of their absorption. This method is also applied to field data. It is concluded from the migration examples that the migration method discussed in this paper is feasible. 展开更多
关键词 one-way wave equation prestack depth migration absorption compensation time-space domain
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Horizontal Distribution and Annual Variations of Fecal Coliform Bacteria in Luoyuan Bay 被引量:2
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作者 蔡雷鸣 《Marine Science Bulletin》 CAS 2010年第1期48-58,共11页
Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100... Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100 mL) to 540 cfu/100 mL in Luoyuan Bay. Values of FCB during August to October were significantly higher than those during January to April during three year period. Monthly changes of FCB values at each year period were mainly due to monthly precipitation. In addition, compared with FCB values in difference sample sites, values of FCB in Bay-heed were significantly higher than those in middle of bay and Bay-mouth, Luoyuan Bay. However, values of FCB in Bay-mouth were significantly less than those in middle of bay. The ratios to the par of FCB in 2003, 2004, and 2005 years were 100%, 98.0%, and 97.9%, respectively. Therefore, we considered that the pollution of FCB of surface marine water in Luoyuan Bay was not serious. 展开更多
关键词 Luoyuan Bay fecal coliform bacteria horizontal distribution annual variations
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Probabilistic durability assessment approach of deteriorating RC bridges 被引量:5
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作者 朱劲松 高嫦娥 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期70-76,共7页
A stochastic finite element computational methodology for probabilistic durability assessment of deteriorating reinforced concrete(RC) bridges by considering the time-and space-dependent variabilities is presented.F... A stochastic finite element computational methodology for probabilistic durability assessment of deteriorating reinforced concrete(RC) bridges by considering the time-and space-dependent variabilities is presented.First,finite element analysis with a smeared cracking approach is implemented.The time-dependent bond-slip relationship between steel and concrete,and the stress-strain relationship of corroded steel bars are considered.Secondly,a stochastic finite element-based computational framework for reliability assessment of deteriorating RC bridges is proposed.The spatial and temporal variability of several parameters affecting the reliability of RC bridges is considered.Based on the data reported by several researchers and from field investigations,the Monte Carlo simulation is used to account for the uncertainties in various parameters,including local and general corrosion in rebars,concrete cover depth,surface chloride concentration,chloride diffusion coefficient,and corrosion rate.Finally,the proposed probabilistic durability assessment approach and framework are applied to evaluate the time-dependent reliability of a girder of a RC bridge located on the Tianjin Binhai New Area in China. 展开更多
关键词 stochastic finite element method space-dependent reliability time-dependent reliability durability assessment concrete carbonation corrosion of rebars
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The Operation Model of Pig Supply Chain Based on Temporal and Spatial Perspectives
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作者 高阔 甘筱青 《Agricultural Science & Technology》 CAS 2014年第9期1624-1628,共5页
This paper constructed pig supply chain based on theoretical study and practical research, then analyzed the operation model of pig supply chain from tem- poral and spatial perspectives. The results showed that from t... This paper constructed pig supply chain based on theoretical study and practical research, then analyzed the operation model of pig supply chain from tem- poral and spatial perspectives. The results showed that from the spatial perspective, pig supply chain had five models of operation, such as vertical integration pig sup- ply chain, quasi-vertical integration pig supply chain (tightly-knit pig supply chain), semi-tightly pig supply chain, loosely-organized pig supply chain and market-oriented pig supply chain. In contrast, from temporal aspect, pig supply chain experiences the pure market transaction, contract form, cooperatives, vertical integration and hori- zontal integration model of operation; the future pig supply chain model in China might be the longitudinal transverse group alliance pig supply chain, namely, the upper vertical integration or quasi-vertical integration (leading processing enterprise + farmer) and down horizontal integration (leading processing enterprises + logistics company + sales), and it would be a kind of competition among interest groups by division of cooperation. 展开更多
关键词 Pig supply chain Operation model TIME SPACE
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A spectrum measurement system for arc plasma with time and spatial indentification
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作者 李志勇 冯立 +1 位作者 杨军涛 范力予 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期75-82,共8页
Spectrum analysis of the plasma has over the years been growing both in methods and instrument, which makes it become a widely used non-contact detection method, without disturbing the arc plasma itself. With noticeab... Spectrum analysis of the plasma has over the years been growing both in methods and instrument, which makes it become a widely used non-contact detection method, without disturbing the arc plasma itself. With noticeable developments in the industry application of the method, a need for careful analysis of the plasma with both time and space identification is desirable. Therefore, a spectral measurement system is developed in this paper for diagnosing arc plasma with time and space identification. With a new hollow probe scanning method, the instrument can be used to provide information like energy distribution of plasma, temperature within the arc plasma, which are of great significance with the requirement of space identification. Furthermore, the system can also be used to capture the instant state of the arc plasma with the synchronic triggering system, which uses high speed photo and electrical signal as the time criterion. The industry applications prove that the system works well for online detection of the arc plasma. 展开更多
关键词 SPECTRUM PLASMA time identification space identification
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游戏中幼儿自主意识的培养策略初探
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作者 白壮霞 《电子乐园》 2019年第1期295-295,共1页
据有关专家调查发现,目前幼儿素质发展中有部分孩子由于生长在 4+2+1 的家庭模式当中,因此造成其自主意识淡薄,这一现 状亟待改善。游戏活动是幼儿园一日活动的基本活动,因此我们以游戏活动为载体,通过转变游戏活动的教育观念、创设轻... 据有关专家调查发现,目前幼儿素质发展中有部分孩子由于生长在 4+2+1 的家庭模式当中,因此造成其自主意识淡薄,这一现 状亟待改善。游戏活动是幼儿园一日活动的基本活动,因此我们以游戏活动为载体,通过转变游戏活动的教育观念、创设轻松愉悦的游戏 环境、提供足够的游戏空间、时间、重视自主游戏过程的指导等策略在游戏中培养幼儿的自主意识。 展开更多
关键词 自主意识 教育观念 游戏环境 空间、时间 指导
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Re-engineering of the forest stand database:case study of Bilahe Forestry Bureau,Inner Mongolia of China 被引量:1
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作者 陈文波 郑蕉 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第3期231-234,共4页
The forest stand database of Bilahe Forestry Bureau, Inner Mongolia of China was taken as an example to demonstrate the whole process of building a temporal geodatabase by means of reengineering. The process was compo... The forest stand database of Bilahe Forestry Bureau, Inner Mongolia of China was taken as an example to demonstrate the whole process of building a temporal geodatabase by means of reengineering. The process was composed of establishing a conceptual data model from the initial database, constructing a logical database by means of mapping, and building a temporal geodatabase with the help of Computer-Aided Software Engineering (CASE) tool and Unified Markup Language (UML). The results showed that as the reengineered forest stand geodatabase was dynamic, it could easily store the historical data and answer time related questions by Structured Query Language (SQL), meanwhile, it maintains the integrity of database and eliminates the redundancy. 展开更多
关键词 RE-ENGINEERING spatial-temporal database CASE tool forest stand
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Detecting Global Vegetation Changes Using Mann-Kendal(MK) Trend Test for 1982–2015 Time Period 被引量:10
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作者 GUO Meng LI Jing +2 位作者 HE Hongshi XU Jiawei JIN Yinghua 《Chinese Geographical Science》 SCIE CSCD 2018年第6期907-919,共13页
Vegetation is the main component of the terrestrial ecosystem and plays a key role in global climate change. Remotely sensed vegetation indices are widely used to detect vegetation trends at large scales. To understan... Vegetation is the main component of the terrestrial ecosystem and plays a key role in global climate change. Remotely sensed vegetation indices are widely used to detect vegetation trends at large scales. To understand the trends of vegetation cover, this research examined the spatial-temporal trends of global vegetation by employing the normalized difference vegetation index(NDVI) from the Advanced Very High Resolution Radiometer(AVHRR) Global Inventory Modeling and Mapping Studies(GIMMS) time series(1982–2015). Ten samples were selected to test the temporal trend of NDVI, and the results show that in arid and semi-arid regions, NDVI showed a deceasing trend, while it showed a growing trend in other regions. Mann-Kendal(MK) trend test results indicate that 83.37% of NDVI pixels exhibited positive trends and that only 16.63% showed negative trends(P < 0.05) during the period from 1982 to 2015. The increasing NDVI trends primarily occurred in tree-covered regions because of forest growth and re-growth and also because of vegetation succession after a forest disturbance. The increasing trend of the NDVI in cropland regions was primarily because of the increasing cropland area and the improvement in planting techniques. This research describes the spatial vegetation trends at a global scale over the past 30+ years, especially for different land cover types. 展开更多
关键词 vegetation trend NDVI3g.v1 Mann-Kendall (MK) trend test land cover types
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Spatio-temporal Difference and Influencing Factors of Environmental Adaptability Measurement of Human-sea Economic System in Liaoning Coastal Area 被引量:6
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作者 LI Bo SHI Zhaoyuan TIAN Chuang 《Chinese Geographical Science》 SCIE CSCD 2018年第2期313-324,共12页
Adaptability theory is an important tool to analyze the degree, mechanism and process of interaction between human and environment, which provides a new perspective for the research of sustainability assessment. Based... Adaptability theory is an important tool to analyze the degree, mechanism and process of interaction between human and environment, which provides a new perspective for the research of sustainability assessment. Based on the entropy weight-TOPSIS method and the panel Tobit model from the perspective of adaptability, spatio-temporal difference and influencing factors of environmental adaptability assessment of human-sea economic system in Liaoning coastal area was measured by using the city panel data from 2000 to 2014. The results indicate that: 1) The environmental adaptability of human-sea economic system in Liaoning coastal area rose slowly from 2000 to 2014, the developing trend of each city was linearly related, and Dalian was in a leading position. 2) The different adaptability elements and adaptability subsystem show polarization phenomenon and completely different regional evolution characteristics. The adaptability of human-sea environment system and human-sea economic system rose slowly and had the characteristics of linear relationship, and the adaptability of human-sea environment system is the main reason for the difference of environmental adaptability of human-sea economic system. 3) Science and technology, environmental management, marine economic development level, port construction are the driving factors of the healthy development of environmental adaptability of urban human-sea economic system. 展开更多
关键词 human-sea economic system ADAPTABILITY human-sea environment system influencing factors Liaoning coastal area
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Spatial and Temporal Pattern of Urban Smart Development in China and Its Driving Mechanism 被引量:3
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作者 CHEN Xiaohong WEI Luyao ZHANG Haifeng 《Chinese Geographical Science》 SCIE CSCD 2018年第4期584-599,共16页
Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly ... Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly in forming scientific and sustainable development concept and responding to new normal strategic opportunities. Based on statistic data of 294 prefecture-level cities and above in China from 2000 to 2015, we analyzed spatial and temporal evolution of urban smart development in China by constructing a dynamic fitting model of urban land expansion, population growth, and economic development as well as the coefficient of variation of urban smart development(CVSD). Further efforts were then made to consider differential distribution regularity of urban smart development so as to understand the driving mechanisms of heterogeneous classification of urban smart development in China from different scales and scale variation. Our results indicate that: 1) the disordered growth tendency of urban cities in China is overall well controlled in the middle, and late research and it mainly presented a doublet coexistence of shrinkage disordered cities and smart developing cities. It is particularly obvious that Northeast China and East China have regarded shrinkage disordered cities and smart developing cities as main development tendency separately. 2) Areas with basic stability and relative variation were relatively dispersed across the time period, but the proportion was far beyond areas with significant variation. It demonstrates a relative equilibrium spatial and temporal differential evolution pattern of prefecture-level cities and above in China, except for Tongling, Lanzhou and Chaoyang. 3) prefecture-level cities and above in China are mostly characterized by shrinkage disordered and smart development classification under the background of different scale and scale variation from 2000–2015; however, the spatial resonance relation is not obvious. 4) There are many interaction factors forming an important driving mechanism in developing the spatial and temporal pattern of urban smart development in China, including natural geographical factors, industrial structure adjustment, human capital radiation, regional traffic accessibility, and government decision-making intervention. 展开更多
关键词 urban smart development spatial and temporal differential pattern driving mechanism interaction factors China
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THERMAL EFFECTS OF BUILDING′S EXTERNAL SURFACES IN CITY——Characteristics of Heat Flux into and out of External Wall Surfaces 被引量:2
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作者 ZHANGYi-ping HEYun-ling +3 位作者 LIUYu-hong MAYou-xin LIYou-rong DOUJun-xia 《Chinese Geographical Science》 SCIE CSCD 2004年第4期343-349,共7页
This study examined the thermal effects of building′s external wall surfaces, using observational data of spatial-temporal distribution of surface temperature, air temperature, and heat flux into and out of external ... This study examined the thermal effects of building′s external wall surfaces, using observational data of spatial-temporal distribution of surface temperature, air temperature, and heat flux into and out of external surface. Results indicate that external wall surface temperature and nearby air temperature vary with the change of orientation, height and season. In general, the external wall surface temperature is lower near the ground, and is higher near the roof, than nearby air temperature. But north wall surface temperature is mostly lower than nearby air temperature at the same height; south wall surface temperature during the daytime in December, and west wall surface temperature all day in August, is respectively higher than nearby air temperature. The heat fluxes into and out of external wall surfaces show the differences that exist in the various orientations, heights and seasons. In December, south wall surface at the lower sites emits heat and north wall surface at the higher sites absorbs heat. In April, all external wall surfaces, emit heat near the ground and absorb heat near the roof. In August, west wall surface all day emits heat, and other wall surfaces just show the commensurate behavior with that in April. 展开更多
关键词 external wall surface thermal effect heat flux intensity spatial-temporal distribution
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City Size Distribution and Its Spatiotemporal Evolution in China 被引量:4
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作者 SHI Lifeng ZHANG Zengxiang +8 位作者 LIU Fang ZHAO Xiaoli WANG Xiao LIU Bin HU Shunguang WEN Qingke ZUO Lijun YI Ling XU Jinyong 《Chinese Geographical Science》 SCIE CSCD 2016年第6期703-714,共12页
Based on the National Land Use/Cover Database of China(NLUD-C) in the end of the 1980s(the 1980s,hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban... Based on the National Land Use/Cover Database of China(NLUD-C) in the end of the 1980s(the 1980s,hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban lands in China. In this study, the spatiotemporal evolutions of urban land size distribution as well as the influence of administrative-level on these cities were explored by combining urban spatial positions and administrative-levels. Results indicate that: 1) City size distribution using urban lands was more practical and reasonable than using non-agricultural population. 2) In the 1980s, cities with ascending urban land rank were centralized in Eastern China, specially the Changjiang(Yangtze) River Delta, the Zhujiang(Pearl) River Delta, and Beijing-Tianjin-Hebei region. Cities in Central, Western, and Northeast China mainly indicated descending urban land rank. 3) The transfer of national development focus resulted in cities with ascending urban land rank becoming evenly distributed nationwide; however, this trend was slightly centralized around Chengdu, Chongqing, and Wuhan in different periods. 4) During the 1980s to 2010, the proportion of cities with ascending urban land rank in provincial capitals, municipalities, and special administrative regions(high-level cities, hereafter) was consistently higher than those in prefecture- and county-level cities except for 2005–2010. The ranks of the majority of the prefecture- and county-level cities were mainly descending, supported by ascending; the proportion of cities with unchanged rank is small. This study breaks through the bottleneck of traditional research in the area of city size distribution by examining urban land replacing the non-agricultural population. The current study also provides scientific explanation for the healthy and reasonable development of urban land as well as the coordinated development of population urbanization and land urbanization. 展开更多
关键词 Chinese city urban land size distribution spatiotemporal evolution remote sensing
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Synchronization and Asynchronization in Two Coupled Excitable Systems 被引量:4
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作者 YUANGuo-Yong ZHANGGuang-Cai +1 位作者 WANGGuang-Rui CHENShi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期459-465,共7页
The synchronization and asynchronization of two coupled excitable systems are investigated. The two systems with different initial configurations, which are separately a single spiral wave (or a travel wave) and the r... The synchronization and asynchronization of two coupled excitable systems are investigated. The two systems with different initial configurations, which are separately a single spiral wave (or a travel wave) and the rest state, can be developed to the synchronizing state with the same spiral wave (or travel wave) in each system, when the coupling is very strong. Decreasing the coupling intensity, two rest states or two different configurations appear in the two systems. The qualitative analysis and interpretation are given. 展开更多
关键词 excitable system spiral wave SYNCHRONIZATION
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RLS channel estimation with adaptive forgetting factor in space-time coded MIMO-OFDM systems 被引量:2
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作者 LIANG Yong-ming LUO Han-wen HUANG Jian-guo 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期507-515,共9页
Considering that channel estimation plays a crucial role in coherent detection, this paper addresses a method of Recursive-least-squares (RLS) channel estimation with adaptive forgetting factor in wireless space-time ... Considering that channel estimation plays a crucial role in coherent detection, this paper addresses a method of Recursive-least-squares (RLS) channel estimation with adaptive forgetting factor in wireless space-time coded multiple-input and multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems. Because there are three different forgetting factor scenarios including adaptive, two-step and conventional ones applied to RLS channel estimation, this paper describes the principle of RLS channel estimation and analyzes the impact of different forgetting factor scenarios on the performances of RLS channel estimation. Simulation results proved that the RLS algorithm with adaptive forgetting factor (RLS-A) outperformed that with two-step forgetting factor (RLS-T) or with conventional forgetting factor (RLS-C) in both estimation accuracy and robustness over the multiple-input multiple-output (MIMO) channel, i.e., a wide-sense stationary uncorrelated scattering (WSSUS) and frequency-selective slowly fading channel. Hence, we can employ the RLS-A method by adjusting forgetting factor adaptively to track and estimate channel state parameters successfully in space-time coded MIMO-OFDM systems. 展开更多
关键词 MIMO-OFDM Channel estimation RLS algorithm Adaptive forgetting factor
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DEVELOPMENT OF A GIS DATA MODEL WITH SPATIAL,TEMPORAL AND ATTRIBUTE COMPONENTS BASED ON OBJECT-ORIENTED APPROACH 被引量:2
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作者 SHI Wenzhong ZHANG Minwen 《Geo-Spatial Information Science》 2000年第1期17-23,共7页
This paper presents a conceptual data model, the STA-model, for handling spatial, temporal and attribute aspects of objects in GIS. The model is developed on the basis of object-oriented modeling approach. This model ... This paper presents a conceptual data model, the STA-model, for handling spatial, temporal and attribute aspects of objects in GIS. The model is developed on the basis of object-oriented modeling approach. This model includes two major parts: (a) modeling the signal objects by STA-object elements, and (b) modeling relationships between STA-objects. As an example, the STA-model is applied for modeling land cover change data with spatial, temporal and attribute components. 展开更多
关键词 OBJECT-ORIENTATION GIS data modeling spatial temporal and attribute model
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