This article elaborated the characteristics of settlement shape in detail with examples. Aiming at the negative effects on settlement shape by construction, we put forward some measures, such as respect for ecological...This article elaborated the characteristics of settlement shape in detail with examples. Aiming at the negative effects on settlement shape by construction, we put forward some measures, such as respect for ecological environment, selection mode of space development, protection of historical features, and excavation of culture connotation, so as to realize the protection of settlement shape.展开更多
The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagg...The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagging of the signal timing plans to traffic conditions. Utilizing the traffic conditions in current and former intervals, the network topology of the state-space neural network (SSNN), which is derived from the geometry of urban arterial routes, is used to predict the optimal timing plan corresponding to the traffic conditions in the next time interval. In order to improve the effectiveness of the SSNN, the extended Kalman filter (EKF) is proposed to train the SSNN instead of conventional approaches. Raw traffic data of the Guangzhou Road, Nanjing and the optimal signal timing plan generated by a multi-objective optimization genetic algorithm are applied to test the performance of the proposed model. The results indicate that compared with the SSNN and the BP neural network, the proposed model can closely match the optimal timing plans in futuristic states with higher efficiency.展开更多
Since nuclear extrusion was rediscovered in young Allium scale by S.H.WU in the years of 1950's systematic investigations on this phenomenon were carried out with various kinds of microscopic techniques a...Since nuclear extrusion was rediscovered in young Allium scale by S.H.WU in the years of 1950's systematic investigations on this phenomenon were carried out with various kinds of microscopic techniques and plant materials to collect more effective evidence to clarify the debate about whether the nuclear extrusion is an artifact or normal event. In the cooperative research of S. H. WU and C. H. LOU the normality of the occurrence of nuclear extrusion either in growing part of plant or in senescent tissue has been confirmed. This event is intimately associated with the physiological state of the tissues/cells and may play an important role in redistribution and reutilization of cell contents. Based on the results obtained a hypothesis of intercellular movement of protoplasm as a means of translocation of organic material in plants was suggested. Chromatin extrusion was also discovered in the pollen mother cells (cytomixis) of certain angiosperms by G. C. ZHENG and his team. Intercellular migration of chromatin appears most frequently at the stage of synizesis. Cytomixis has been studied in relation to variation and evolution. Chromosome aberration has been considered to be closely associated with chromatin extrusion. By vital microscopic observations of the live tissues of garlic (Allium sativum L.) bud and wheat (Triticum aestivum L.) ovule combined with cinemicroscopy and video recording it has been uncovered that, not only the nuclear material but also the cytoplasm could traverse the intercellular channels by vigorous contraction and expansion, and they may simultaneously extrude out of a cell but often asynchronously migrate from one cell to another. The involvement of cytoplasmic constituents in intercellular migration was also detected in pollen mother cells with electron microscopy. Regarding the mechanism of intercellular movement a series of experiments provide convincing evidence showing that this kind of movement is an active metabolic process closely coupled with energy metabolism, and the motive power for driving the extrusion may be supplied by the contractile proteins in protoplasm.展开更多
A 3D synchronism deployable antenna was designed, analyzed, and manufactured by our research group. This an-tenna consists of tetrahedral elements from central element. Because there are springs at the ends of some of...A 3D synchronism deployable antenna was designed, analyzed, and manufactured by our research group. This an-tenna consists of tetrahedral elements from central element. Because there are springs at the ends of some of the rods, spider joints are applied. For analysis purpose, the structure is simplified and modelled by using 2D beam elements that have no bending stiffness. Displacement vectors are defined to include two translational displacements and one torsional displacement. The stiff-ness matrix derived by this method is relatively simple and well defined. The analysis results generated by using software de-veloped by our research group agreed very well with available test data.展开更多
Shift-share analysis has been confirmed a useful approach in the study of regional economics and many kinds of extended shift-share models have been advanced and put into practice in economic studies, but few have hit...Shift-share analysis has been confirmed a useful approach in the study of regional economics and many kinds of extended shift-share models have been advanced and put into practice in economic studies, but few have hitherto been introduced and applied to the tourism research in China. Moreover understanding the spatially competitive relationship is of paramount importance for marketers, developers, and planners involved in tourism strategy development. Based on international tourism receipts from 1995 to 2004, this study aims at probing into the spatial competitiveness of interna- tional tourism in Jiangsu Province in comparison with its neighbors by applying a spatially extended shift-share model and a modified dynamic shift-share model. The empirical results illustrate that exceptional years may exist in the ap- plication of dynamic shift-share models. To solve this issue, modifications to dynamic shift-share model are put forward. The analytical results are not only presented but also explained by the comparison of background conditions of tourism development between Jiangsu and its key competitors. The conclusions can be drawn that the growth of international tourism receipts in Jiangsu mainly attributes to the national component and the competitive component and Zhejiang is the most important rival to Jiangsu during the period of 1995-2004. In order to upgrade the tourism competitiveness, it is indispensable for Jiangsu to take proper positioning, promoting and marketing strategies and to cooperate and integrate with its main rivals.展开更多
We discuss the existence results of the parabolic evolution equation d(x(t)+g(t,x(t)))/dt+A(t)x(t)=f(t,x(t)) in Banach spaces, where A(t) generates an evolution system and functions f,g are continuous. We get the theo...We discuss the existence results of the parabolic evolution equation d(x(t)+g(t,x(t)))/dt+A(t)x(t)=f(t,x(t)) in Banach spaces, where A(t) generates an evolution system and functions f,g are continuous. We get the theorem of existence of a mild solution, the theorem of existence and uniqueness of a mild solution and the theorem of existence and uniqueness of an S-classical (semi-classical) solution. We extend the cases when g(t)=0 or A(t)=A.展开更多
We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di...We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di- rection analysis and landscape pattern analysis, were employed. The results show that: 1) the residential land grew very rapidly in Hefei from 1978 to 2004, and the increased land was distributed mainly in the central city zone surrounded by a moat; however, after 1994, it was distributed mainly outside the 1th Ring Road; 2) the expansion speeds were very different in different directions: there exists a fastest expansion of residential land in the directions of NE-NNE, SW and SSE, and a slowest one in the directions of E and SEE; 3) the residential land growth went through four stages: slow circular expansion in 1978-1991, 'axes + fan wings' expansion in 1991-1994, more rapid circular expansion in 1994-2000 and 'fan-wings' expansion in 2000-2004; 4) the expansion intensity was also different in all directions in the period of 1978 to 1994, and the most was in SW and then NW; and 5) there were more and more residential land area, and the spatial agglomeration was improved increasingly.展开更多
The existing researches on the influence of information and communication technology (ICT) are mainly focused on human activity, whilst with few efforts on urban space. In the e-society, the widespread adoption of 1...The existing researches on the influence of information and communication technology (ICT) are mainly focused on human activity, whilst with few efforts on urban space. In the e-society, the widespread adoption of 1CT devices not only affects almost every aspect of people's daily life and thereby reshapes the spatial development of regions and cities, but also generates a large amount of real-time activity data with location information. These georeferenced data, however, have relatively recently attracted attention from geographers. Adapted from Lynch's framework based on people's perceptions, this paper proposes a framework of urban spatial struc- ture based on people's actual activity, including five elements, namely activity path, activity node, central activity zone (CAZ), activity district, and activity edge. In the empirical study, by using one week's check-in tweets (from February 25 to March 3 in 2013) collected in Nanjing City, the five elements are recognized and analyzed. Through the comparison between our results and urban spatial structure based on population (and land use), we argue that ICT uses: 1) lead to polarize, rather than to smooth, the urban structural hierarchy, due to the dual role of distance; 2) enable a partial decoupling of activity and activity space node, which challenges our conventional under- standing of the role of home and the utility of travel; 3) blur the boundaries of activity districts and hence may play a positive role in enriching districts' functions, which should not be overlooked in the current urban transformation in China.展开更多
With the development of the Internet, the Internet language-a new social variant of language comes into being. Owing to its distinctive features, the Internet language draws extensive attention and evokes dispute. Sho...With the development of the Internet, the Internet language-a new social variant of language comes into being. Owing to its distinctive features, the Internet language draws extensive attention and evokes dispute. Should we make laws to restrict its development or be magnanimous and tolerant? The present authors think that the dispute reflects the clash between the traditional culture and the "fast food" culture. The two cultures would co-exist harmoniously and co-develop healthily only if we cherish the law in the development of language and grasp the indirect correlation between them.展开更多
This paper presents an integrated study of urban spatial expansion in the Hexi Corridor, Gansu Province, China based on TM, ETM remote sensing data in 1987, 1990, 1995, 2000, 2006 and 2011. The study explores the char...This paper presents an integrated study of urban spatial expansion in the Hexi Corridor, Gansu Province, China based on TM, ETM remote sensing data in 1987, 1990, 1995, 2000, 2006 and 2011. The study explores the characteristics of urban spatial expansion and dynamic mechanism by using expansion speed index, expansion intensity index, compact index, fractal dimension, and extended flexibility index. We built the index system of influencing factors of urban spatial expansion by using the grey incidence model. The results showed that urban spatial expansion rate in the Hexi Corridor has been on the upward trend since 1987. Expansion intensity showed an obvious upward trend, however, the upward trend varied in different urban areas. In addition, the urban structure was loose relatively, but the urban compactness was more obvious. The urban spatial form tended to be simple, and the urban land use tended to become more intensive. Urban spatial expansion experienced several stages: padding internally, external expansion and padding internally. The main driving factors of urban spatial expansion are not the urban water resources and the oasis scale, but one or several factors such as economy, traffic, population, resource and national policy.展开更多
Tourism spatial distribution has played an important role in local tourism development.The tourism function and development direction can be determined,as well as the complementary resources can be realized through in...Tourism spatial distribution has played an important role in local tourism development.The tourism function and development direction can be determined,as well as the complementary resources can be realized through investigating the status of tourism in the region,identifying the status of tourism development and division of the tourism spatial distribution.The Mongolian Autonomous Prefecture of Xinjiang Bortala has been selected as a study area.Status of tourism development,tourism spatial distribution and some problem in Bortala were summarized.Finally,countermeasures were put forward pertinently.展开更多
Under the theoretical framework of the New Trade Theory and the New Economic Geography, Home Market Effects (HMEs) is considered to be important sources of comparative advantage and significant reasons for industry ag...Under the theoretical framework of the New Trade Theory and the New Economic Geography, Home Market Effects (HMEs) is considered to be important sources of comparative advantage and significant reasons for industry agglomeration. Through the analysis on the input-output tables in China, the paper confirms the existence of HMEs for the manufacturing industries and their export trades on the national and provincial level in China. Several conclusions have been drawn in this study. Firstly, there exist prominent HMEs for manufacturing industries related with nondurable goods and materials in China. Secondly, 10 of the 15 kinds of manufacturing industries considered in this study display the existence of HMEs. Thirdly, the comparative advantage of factor endowment for the export trade of manufacturing industries is declining, while HMEs for them are increasing. Fourthly, among the 30 provincial regions studied in this paper, 11 regions show the existence of HMEs, most of which are located in the eastern coast region. This paper illustrates the simultaneous existence of the comparative advantage of factor endowment and scale economies of HMEs for China's manufacturing industries. HMEs will not only be the new dynamic for the increase of manufacturing industries and their export trade, but also be the primary power for urban economic growth, industry improvement, and urban space expansion for China.展开更多
A nonlinear analysis of urban evolution is made by using of spatial autocorrelation theory. A first-order nonlinear autoregression model based on Clark’s negative exponential model is proposed to show urban populatio...A nonlinear analysis of urban evolution is made by using of spatial autocorrelation theory. A first-order nonlinear autoregression model based on Clark’s negative exponential model is proposed to show urban population density. The new method and model are applied to Hangzhou City, China, as an example. The average distance of population activities, the auto-correlation coefficient of urban population density, and the auto-regressive function values all show trends of gradual increase from 1964 to 2000, but there always is a sharp first-order cutoff in the partial auto- correlations. These results indicate that urban development is a process of localization. The discovery of urban locality is significant to improve the cellular-automata-based urban simulation of modeling spatial complexity.展开更多
After 1995, Tibet entered the stage of accelerated urbanization. The large floating population fi'om outside Tibet has become the driving force for urban expansion and the rising of urbanization rate. After analyzing...After 1995, Tibet entered the stage of accelerated urbanization. The large floating population fi'om outside Tibet has become the driving force for urban expansion and the rising of urbanization rate. After analyzing the changes of urban functions and spatial structure of urban system in Tibet, this paper argues that before 1995 the urbanization in Tibet was mainly driven by administrative function, resulting in certain population migration, whereas in the past decade economic function has become the key factor accelerating urban expansion with the market mechanism creating large-scale inflow of population. The floating population-based urbanization and high population growth in the agricultural and pastoral areas of Tibet has promoted the regional economic prosperity, but exerted resources and environmental pressure and brought some problems for Tibetan culture protection at the same time. The conflicts and contradictions between urbanization and the sustainability of natural resources, environment and social development have been intensified. Addressing these problems, this paper proposes some countermeasures for improving the sustainability of Tibetan urbanization.展开更多
The growing attention on urban tourism was very widespread. There are two angles to study urban tourism: supply-side and demand-side. And the supply-side of the tourism remains very important. The RBD (Recreation Busi...The growing attention on urban tourism was very widespread. There are two angles to study urban tourism: supply-side and demand-side. And the supply-side of the tourism remains very important. The RBD (Recreation Business District) is a useful framework to understand the components of urban tourism and how they fit together. The paper begins with a review on the RBD and the spatial structure of tourism in urban areas and then attempts to develop a more general understanding of the spatial structure evolution of RBDs in a tourist-historic city-Suzhou. The spatial structures and functions of the RBDs in Suzhou are examined, based on field observations, interviews with city officials and industry leaders, and a review of available documents. The urban tourism of Suzhou has developed in a range of contexts, that various types of RBDs have emerged as a result of different urban development strategies. The spatial structure has evolved from the past "Single-cored Structure" to "Double-cored Structure" at present, and then to "Chain Structure" in the future. The spatial form and evolution of RBD in Suzhou are closely relative with its urban spatial expansion. Urban area dispersal is the prerequisite of the emergence of the RBD. Planning and constructing the RBD becomes a new impetus to urban growth or renewal. Finally, a number of strategies for planning and developing the RBD in Suzhou are suggested. The different RBDs should adopt different strategies. Intensification can be the possible strategy for the RBDs in the ancient city. Accreting with the urban theme park or engrafting on the Jinji Lake is suggested respectively for the RBD in the Suzhou New District and the Suzhou Industrial Park.展开更多
Based on the remote sensing images of urban land use of Chongqing City Proper in the last 30years(from 1978 to 2011),The paper focuses on the impact of urban spatial expansion on urban ecosystem service.The charactere...Based on the remote sensing images of urban land use of Chongqing City Proper in the last 30years(from 1978 to 2011),The paper focuses on the impact of urban spatial expansion on urban ecosystem service.The charactereristics of urban spatial expansion pattern are expressed by Landscape Expansion Index and Index of Fractal Dimension.Taking advantage of calculation of these two indices,changes of the ecological service values in the main urban area of Chongqing caused by the variation of urban expansion patterns are evaluated and the interrelationship is analyzed.The main conclusions and results are as follows;in Chongqing City Proper,the ecological service value decreased rapidly from 1978 to 2011,especially in the period of 2002-2011.Urban spatial expansion pattern has exerted significant impact on urban ecosystem service value.Edge-expansion pattern broke into a great deal of urban enclaves and caused the disadvantage effect of the function of urban ecological system.At the same time,negative correlation existed between the indices of fractal dimension and the ecosystem service value.展开更多
基金Supported by the 11th 5-year Scientific Supporting Project Fund of the Ministry of Science and Technology(2006BAJ01A12-06)the 11th 5-years Planning Philosophy and Social Science Project of Sichuan Province(SC06B014)~~
文摘This article elaborated the characteristics of settlement shape in detail with examples. Aiming at the negative effects on settlement shape by construction, we put forward some measures, such as respect for ecological environment, selection mode of space development, protection of historical features, and excavation of culture connotation, so as to realize the protection of settlement shape.
基金The National Natural Science Foundation of China (No.50422283)the Soft Science Research Project of Ministry of Housing and Urban-Rural Development of China (No.2008-K5-14)
文摘The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagging of the signal timing plans to traffic conditions. Utilizing the traffic conditions in current and former intervals, the network topology of the state-space neural network (SSNN), which is derived from the geometry of urban arterial routes, is used to predict the optimal timing plan corresponding to the traffic conditions in the next time interval. In order to improve the effectiveness of the SSNN, the extended Kalman filter (EKF) is proposed to train the SSNN instead of conventional approaches. Raw traffic data of the Guangzhou Road, Nanjing and the optimal signal timing plan generated by a multi-objective optimization genetic algorithm are applied to test the performance of the proposed model. The results indicate that compared with the SSNN and the BP neural network, the proposed model can closely match the optimal timing plans in futuristic states with higher efficiency.
文摘Since nuclear extrusion was rediscovered in young Allium scale by S.H.WU in the years of 1950's systematic investigations on this phenomenon were carried out with various kinds of microscopic techniques and plant materials to collect more effective evidence to clarify the debate about whether the nuclear extrusion is an artifact or normal event. In the cooperative research of S. H. WU and C. H. LOU the normality of the occurrence of nuclear extrusion either in growing part of plant or in senescent tissue has been confirmed. This event is intimately associated with the physiological state of the tissues/cells and may play an important role in redistribution and reutilization of cell contents. Based on the results obtained a hypothesis of intercellular movement of protoplasm as a means of translocation of organic material in plants was suggested. Chromatin extrusion was also discovered in the pollen mother cells (cytomixis) of certain angiosperms by G. C. ZHENG and his team. Intercellular migration of chromatin appears most frequently at the stage of synizesis. Cytomixis has been studied in relation to variation and evolution. Chromosome aberration has been considered to be closely associated with chromatin extrusion. By vital microscopic observations of the live tissues of garlic (Allium sativum L.) bud and wheat (Triticum aestivum L.) ovule combined with cinemicroscopy and video recording it has been uncovered that, not only the nuclear material but also the cytoplasm could traverse the intercellular channels by vigorous contraction and expansion, and they may simultaneously extrude out of a cell but often asynchronously migrate from one cell to another. The involvement of cytoplasmic constituents in intercellular migration was also detected in pollen mother cells with electron microscopy. Regarding the mechanism of intercellular movement a series of experiments provide convincing evidence showing that this kind of movement is an active metabolic process closely coupled with energy metabolism, and the motive power for driving the extrusion may be supplied by the contractile proteins in protoplasm.
基金Project (No. 863-2-4) supported by the National Basic Research Program (863) of China
文摘A 3D synchronism deployable antenna was designed, analyzed, and manufactured by our research group. This an-tenna consists of tetrahedral elements from central element. Because there are springs at the ends of some of the rods, spider joints are applied. For analysis purpose, the structure is simplified and modelled by using 2D beam elements that have no bending stiffness. Displacement vectors are defined to include two translational displacements and one torsional displacement. The stiff-ness matrix derived by this method is relatively simple and well defined. The analysis results generated by using software de-veloped by our research group agreed very well with available test data.
基金Under the auspices of the National Natural Science Foundation of China (No. 40371030)
文摘Shift-share analysis has been confirmed a useful approach in the study of regional economics and many kinds of extended shift-share models have been advanced and put into practice in economic studies, but few have hitherto been introduced and applied to the tourism research in China. Moreover understanding the spatially competitive relationship is of paramount importance for marketers, developers, and planners involved in tourism strategy development. Based on international tourism receipts from 1995 to 2004, this study aims at probing into the spatial competitiveness of interna- tional tourism in Jiangsu Province in comparison with its neighbors by applying a spatially extended shift-share model and a modified dynamic shift-share model. The empirical results illustrate that exceptional years may exist in the ap- plication of dynamic shift-share models. To solve this issue, modifications to dynamic shift-share model are put forward. The analytical results are not only presented but also explained by the comparison of background conditions of tourism development between Jiangsu and its key competitors. The conclusions can be drawn that the growth of international tourism receipts in Jiangsu mainly attributes to the national component and the competitive component and Zhejiang is the most important rival to Jiangsu during the period of 1995-2004. In order to upgrade the tourism competitiveness, it is indispensable for Jiangsu to take proper positioning, promoting and marketing strategies and to cooperate and integrate with its main rivals.
文摘We discuss the existence results of the parabolic evolution equation d(x(t)+g(t,x(t)))/dt+A(t)x(t)=f(t,x(t)) in Banach spaces, where A(t) generates an evolution system and functions f,g are continuous. We get the theorem of existence of a mild solution, the theorem of existence and uniqueness of a mild solution and the theorem of existence and uniqueness of an S-classical (semi-classical) solution. We extend the cases when g(t)=0 or A(t)=A.
基金Under the auspices of the National Natural Science Foundation of China (No. 40371038)
文摘We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di- rection analysis and landscape pattern analysis, were employed. The results show that: 1) the residential land grew very rapidly in Hefei from 1978 to 2004, and the increased land was distributed mainly in the central city zone surrounded by a moat; however, after 1994, it was distributed mainly outside the 1th Ring Road; 2) the expansion speeds were very different in different directions: there exists a fastest expansion of residential land in the directions of NE-NNE, SW and SSE, and a slowest one in the directions of E and SEE; 3) the residential land growth went through four stages: slow circular expansion in 1978-1991, 'axes + fan wings' expansion in 1991-1994, more rapid circular expansion in 1994-2000 and 'fan-wings' expansion in 2000-2004; 4) the expansion intensity was also different in all directions in the period of 1978 to 1994, and the most was in SW and then NW; and 5) there were more and more residential land area, and the spatial agglomeration was improved increasingly.
基金National Natural Science Foundation of China(No.40971094)
文摘The existing researches on the influence of information and communication technology (ICT) are mainly focused on human activity, whilst with few efforts on urban space. In the e-society, the widespread adoption of 1CT devices not only affects almost every aspect of people's daily life and thereby reshapes the spatial development of regions and cities, but also generates a large amount of real-time activity data with location information. These georeferenced data, however, have relatively recently attracted attention from geographers. Adapted from Lynch's framework based on people's perceptions, this paper proposes a framework of urban spatial struc- ture based on people's actual activity, including five elements, namely activity path, activity node, central activity zone (CAZ), activity district, and activity edge. In the empirical study, by using one week's check-in tweets (from February 25 to March 3 in 2013) collected in Nanjing City, the five elements are recognized and analyzed. Through the comparison between our results and urban spatial structure based on population (and land use), we argue that ICT uses: 1) lead to polarize, rather than to smooth, the urban structural hierarchy, due to the dual role of distance; 2) enable a partial decoupling of activity and activity space node, which challenges our conventional under- standing of the role of home and the utility of travel; 3) blur the boundaries of activity districts and hence may play a positive role in enriching districts' functions, which should not be overlooked in the current urban transformation in China.
文摘With the development of the Internet, the Internet language-a new social variant of language comes into being. Owing to its distinctive features, the Internet language draws extensive attention and evokes dispute. Should we make laws to restrict its development or be magnanimous and tolerant? The present authors think that the dispute reflects the clash between the traditional culture and the "fast food" culture. The two cultures would co-exist harmoniously and co-develop healthily only if we cherish the law in the development of language and grasp the indirect correlation between them.
基金Under the auspices of National Natural Science Foundation of China(No.41271133,41261104)National Social Science Foundation of China(No.12CTJ001)
文摘This paper presents an integrated study of urban spatial expansion in the Hexi Corridor, Gansu Province, China based on TM, ETM remote sensing data in 1987, 1990, 1995, 2000, 2006 and 2011. The study explores the characteristics of urban spatial expansion and dynamic mechanism by using expansion speed index, expansion intensity index, compact index, fractal dimension, and extended flexibility index. We built the index system of influencing factors of urban spatial expansion by using the grey incidence model. The results showed that urban spatial expansion rate in the Hexi Corridor has been on the upward trend since 1987. Expansion intensity showed an obvious upward trend, however, the upward trend varied in different urban areas. In addition, the urban structure was loose relatively, but the urban compactness was more obvious. The urban spatial form tended to be simple, and the urban land use tended to become more intensive. Urban spatial expansion experienced several stages: padding internally, external expansion and padding internally. The main driving factors of urban spatial expansion are not the urban water resources and the oasis scale, but one or several factors such as economy, traffic, population, resource and national policy.
文摘Tourism spatial distribution has played an important role in local tourism development.The tourism function and development direction can be determined,as well as the complementary resources can be realized through investigating the status of tourism in the region,identifying the status of tourism development and division of the tourism spatial distribution.The Mongolian Autonomous Prefecture of Xinjiang Bortala has been selected as a study area.Status of tourism development,tourism spatial distribution and some problem in Bortala were summarized.Finally,countermeasures were put forward pertinently.
基金Under the auspices of Humanities and Social Sciences Research Fund Project of Ministry of Education of China(No. 2009JJD790014, 10YJA790005)
文摘Under the theoretical framework of the New Trade Theory and the New Economic Geography, Home Market Effects (HMEs) is considered to be important sources of comparative advantage and significant reasons for industry agglomeration. Through the analysis on the input-output tables in China, the paper confirms the existence of HMEs for the manufacturing industries and their export trades on the national and provincial level in China. Several conclusions have been drawn in this study. Firstly, there exist prominent HMEs for manufacturing industries related with nondurable goods and materials in China. Secondly, 10 of the 15 kinds of manufacturing industries considered in this study display the existence of HMEs. Thirdly, the comparative advantage of factor endowment for the export trade of manufacturing industries is declining, while HMEs for them are increasing. Fourthly, among the 30 provincial regions studied in this paper, 11 regions show the existence of HMEs, most of which are located in the eastern coast region. This paper illustrates the simultaneous existence of the comparative advantage of factor endowment and scale economies of HMEs for China's manufacturing industries. HMEs will not only be the new dynamic for the increase of manufacturing industries and their export trade, but also be the primary power for urban economic growth, industry improvement, and urban space expansion for China.
基金Under the auspices of the National Natural Science Foundation of China (No. 40371039)
文摘A nonlinear analysis of urban evolution is made by using of spatial autocorrelation theory. A first-order nonlinear autoregression model based on Clark’s negative exponential model is proposed to show urban population density. The new method and model are applied to Hangzhou City, China, as an example. The average distance of population activities, the auto-correlation coefficient of urban population density, and the auto-regressive function values all show trends of gradual increase from 1964 to 2000, but there always is a sharp first-order cutoff in the partial auto- correlations. These results indicate that urban development is a process of localization. The discovery of urban locality is significant to improve the cellular-automata-based urban simulation of modeling spatial complexity.
基金Under the auspices of Key Program of National Natural Science Foundation of China (No. 40830741)
文摘After 1995, Tibet entered the stage of accelerated urbanization. The large floating population fi'om outside Tibet has become the driving force for urban expansion and the rising of urbanization rate. After analyzing the changes of urban functions and spatial structure of urban system in Tibet, this paper argues that before 1995 the urbanization in Tibet was mainly driven by administrative function, resulting in certain population migration, whereas in the past decade economic function has become the key factor accelerating urban expansion with the market mechanism creating large-scale inflow of population. The floating population-based urbanization and high population growth in the agricultural and pastoral areas of Tibet has promoted the regional economic prosperity, but exerted resources and environmental pressure and brought some problems for Tibetan culture protection at the same time. The conflicts and contradictions between urbanization and the sustainability of natural resources, environment and social development have been intensified. Addressing these problems, this paper proposes some countermeasures for improving the sustainability of Tibetan urbanization.
文摘The growing attention on urban tourism was very widespread. There are two angles to study urban tourism: supply-side and demand-side. And the supply-side of the tourism remains very important. The RBD (Recreation Business District) is a useful framework to understand the components of urban tourism and how they fit together. The paper begins with a review on the RBD and the spatial structure of tourism in urban areas and then attempts to develop a more general understanding of the spatial structure evolution of RBDs in a tourist-historic city-Suzhou. The spatial structures and functions of the RBDs in Suzhou are examined, based on field observations, interviews with city officials and industry leaders, and a review of available documents. The urban tourism of Suzhou has developed in a range of contexts, that various types of RBDs have emerged as a result of different urban development strategies. The spatial structure has evolved from the past "Single-cored Structure" to "Double-cored Structure" at present, and then to "Chain Structure" in the future. The spatial form and evolution of RBD in Suzhou are closely relative with its urban spatial expansion. Urban area dispersal is the prerequisite of the emergence of the RBD. Planning and constructing the RBD becomes a new impetus to urban growth or renewal. Finally, a number of strategies for planning and developing the RBD in Suzhou are suggested. The different RBDs should adopt different strategies. Intensification can be the possible strategy for the RBDs in the ancient city. Accreting with the urban theme park or engrafting on the Jinji Lake is suggested respectively for the RBD in the Suzhou New District and the Suzhou Industrial Park.
基金Supported by the Key Technologies R&D Program(No.2012 BAJ23B05)the National Natural Science Foundation of China(No.40701179)
文摘Based on the remote sensing images of urban land use of Chongqing City Proper in the last 30years(from 1978 to 2011),The paper focuses on the impact of urban spatial expansion on urban ecosystem service.The charactereristics of urban spatial expansion pattern are expressed by Landscape Expansion Index and Index of Fractal Dimension.Taking advantage of calculation of these two indices,changes of the ecological service values in the main urban area of Chongqing caused by the variation of urban expansion patterns are evaluated and the interrelationship is analyzed.The main conclusions and results are as follows;in Chongqing City Proper,the ecological service value decreased rapidly from 1978 to 2011,especially in the period of 2002-2011.Urban spatial expansion pattern has exerted significant impact on urban ecosystem service value.Edge-expansion pattern broke into a great deal of urban enclaves and caused the disadvantage effect of the function of urban ecological system.At the same time,negative correlation existed between the indices of fractal dimension and the ecosystem service value.