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
Urbanization in modern times led to a series of development strategies that brought new opportunities in China. Rapid urbanization caused severe stress to the ecosystems and the environment. Using the center-of-gravit...Urbanization in modern times led to a series of development strategies that brought new opportunities in China. Rapid urbanization caused severe stress to the ecosystems and the environment. Using the center-of-gravity(COG) method and parameters such as population, economy, and land, we studied the urbanization pattern in Songhua River Basin and its southern source sub-basin from 1990 to 2010. Urbanization was analyzed based on the COG position, eccentric distance, movement direction of COG, and distance of COG movement. Various characteristics of urbanization in the southern source sub-basin of the Songhua River were explained in relation to the whole Songhua River Basin. Urbanization in the southern source sub-basin of the Songhua River is balanced, relatively advanced, and stable compared to the whole Songhua River Basin. The average eccentric distance between the urbanization COGs in the Songhua River′s south source basin indicated rapid expansion of land urbanization during the span of this study. A basic pattern of urbanization COG in the whole Songhua Basin was observed, but there existed differences among the three aspects of urbanization process. Land urbanization is still in its active stage, so future studies should focus on analysis of such urbanization trends.展开更多
After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks （VANETs） by a qualitative comparison, this paper proposes a novel self-adaptive routing protocol, named ARPP. Wit...After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks （VANETs） by a qualitative comparison, this paper proposes a novel self-adaptive routing protocol, named ARPP. With respect to the specific characteristics of VANETs, the proposed routing protocol adopts a dynamic topology establishment and time-varying control message sending mechanism. A direction-based forwarding strategy and a specific warning solution enhance the routing performance in ARPP. Simulation results show that the ARPP protocol outperforms the classic AODV in urban vehicle environment.展开更多
The paper investigates the places of an urban region inside a Biosphere Reserve in southern Brazil and explores the potentialities for synergies between their biological and sociocultural systems. It assumes： （i） t...The paper investigates the places of an urban region inside a Biosphere Reserve in southern Brazil and explores the potentialities for synergies between their biological and sociocultural systems. It assumes： （i） the perception of their regional rootedness works beneficially for enhancing sustainability; （ii） current progress in place＇s conceptualization helps in the quest for sustainability, since the core factors of the concept deal precisely with the relationships between people and environment. The paper works both with the perception of existing, as invented places, analysing the perception they stimulate. Real places are seen as socially constructed; invented places, as economically promoted. Selection of empirical regional cases is based on their： perception （real and invented places）; scale （urban and ex-urban）; management （public or private）. In the area of Architecture-Urbanism, place is a created environmental form, imbued with symbolic significance to its users. In the present shift of paradigms from modernism to postmodernism, the discipline evolves towards a more thorough concern with the philosophical implications of places on phenomenological grounds. Also, the making and marketing of new places become increasingly accepted as influential tools to foster prosperity and well-being, by means of the economic development attributed to the creation of places. The concerted private and public management of the region＇s places and the restrained design they presently employ are providing grounds for an affluent development, showing a wise use of the regional resources. Altogether, it seems inhabitants have learned how to work in conjunction with the environment. This hints at a clear manifestation of sustainable development, worth investigating. Presumably, the concept of place, positioned as it is at the very interface of physical, social, economic and behavioural disciplines, seems to provide a likely means for tackling the challenges for a sustained regional development planning.展开更多
Integrating various resource advantages including location, land, coastline and waterway, Heng- sha, Shanghai will be the new space of strategic development in the future （especially after 2020）. Inspired by marine ...Integrating various resource advantages including location, land, coastline and waterway, Heng- sha, Shanghai will be the new space of strategic development in the future （especially after 2020）. Inspired by marine economic development and continual establishment for new strategic space of coastal cities, in this pa- per we will take the strategic development direction of Hengsha new space into consideration when enlarging on the positioning of the new development space in Hengsha, which includes international logistic center （free har- bor and logistic transshipment center）, modem port industry, high-end services, tourism, leisure, and recre- ation and ecological village in downtown area.展开更多
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.
基金National Key Technologies R&D Program(No.2012BAD22B04)Talent Introduction Project of Jilin Province
文摘Urbanization in modern times led to a series of development strategies that brought new opportunities in China. Rapid urbanization caused severe stress to the ecosystems and the environment. Using the center-of-gravity(COG) method and parameters such as population, economy, and land, we studied the urbanization pattern in Songhua River Basin and its southern source sub-basin from 1990 to 2010. Urbanization was analyzed based on the COG position, eccentric distance, movement direction of COG, and distance of COG movement. Various characteristics of urbanization in the southern source sub-basin of the Songhua River were explained in relation to the whole Songhua River Basin. Urbanization in the southern source sub-basin of the Songhua River is balanced, relatively advanced, and stable compared to the whole Songhua River Basin. The average eccentric distance between the urbanization COGs in the Songhua River′s south source basin indicated rapid expansion of land urbanization during the span of this study. A basic pattern of urbanization COG in the whole Songhua Basin was observed, but there existed differences among the three aspects of urbanization process. Land urbanization is still in its active stage, so future studies should focus on analysis of such urbanization trends.
基金Supported by the National Natural Science Foundation of China （No.61070182, No. 60873192, No. 61170225）
文摘After presenting weaknesses of several classic routing protocols applied in vehicular ad hoc networks （VANETs） by a qualitative comparison, this paper proposes a novel self-adaptive routing protocol, named ARPP. With respect to the specific characteristics of VANETs, the proposed routing protocol adopts a dynamic topology establishment and time-varying control message sending mechanism. A direction-based forwarding strategy and a specific warning solution enhance the routing performance in ARPP. Simulation results show that the ARPP protocol outperforms the classic AODV in urban vehicle environment.
文摘The paper investigates the places of an urban region inside a Biosphere Reserve in southern Brazil and explores the potentialities for synergies between their biological and sociocultural systems. It assumes： （i） the perception of their regional rootedness works beneficially for enhancing sustainability; （ii） current progress in place＇s conceptualization helps in the quest for sustainability, since the core factors of the concept deal precisely with the relationships between people and environment. The paper works both with the perception of existing, as invented places, analysing the perception they stimulate. Real places are seen as socially constructed; invented places, as economically promoted. Selection of empirical regional cases is based on their： perception （real and invented places）; scale （urban and ex-urban）; management （public or private）. In the area of Architecture-Urbanism, place is a created environmental form, imbued with symbolic significance to its users. In the present shift of paradigms from modernism to postmodernism, the discipline evolves towards a more thorough concern with the philosophical implications of places on phenomenological grounds. Also, the making and marketing of new places become increasingly accepted as influential tools to foster prosperity and well-being, by means of the economic development attributed to the creation of places. The concerted private and public management of the region＇s places and the restrained design they presently employ are providing grounds for an affluent development, showing a wise use of the regional resources. Altogether, it seems inhabitants have learned how to work in conjunction with the environment. This hints at a clear manifestation of sustainable development, worth investigating. Presumably, the concept of place, positioned as it is at the very interface of physical, social, economic and behavioural disciplines, seems to provide a likely means for tackling the challenges for a sustained regional development planning.
文摘Integrating various resource advantages including location, land, coastline and waterway, Heng- sha, Shanghai will be the new space of strategic development in the future （especially after 2020）. Inspired by marine economic development and continual establishment for new strategic space of coastal cities, in this pa- per we will take the strategic development direction of Hengsha new space into consideration when enlarging on the positioning of the new development space in Hengsha, which includes international logistic center （free har- bor and logistic transshipment center）, modem port industry, high-end services, tourism, leisure, and recre- ation and ecological village in downtown area.
