China is one of the countries with the most serious flooding disasters.In China,above 70% of big cities,50% of population and 75% of industrial and agricultural output value are distributed in eastern coastal areas wi...China is one of the countries with the most serious flooding disasters.In China,above 70% of big cities,50% of population and 75% of industrial and agricultural output value are distributed in eastern coastal areas with serious flooding.Therefore,enhancement of theoretical study and experience summarization of urban flood control is of great theoretical and practical significance.As economy is developing rapidly,urban scale is expanding fast,and urban flood control stand is promoted.Urban flood control calls for new concept and methods.This paper makes a systematic summarization of concept evolution and advanced methods concerning urban flood control at home and abroad.The concept of urban flood control has transformed from simple flood control and drainage to coexistence with and use of flood.Flood control measures have transferred form emphasis upon engineering ones to priority to both engineering and non-engineering ones,with special attention to ecological flood control,such as making full use of ecological revetment,ecological realignment of a river,multi-objective management of urban flood detention region,turning flood into resources and utilization of wetlands.展开更多
This paper provides an analysis of the rapid expansion in number and population of large cities in the proeess of China＇s urbanization and the relative decline of small and medium-sized cities and examines the root c...This paper provides an analysis of the rapid expansion in number and population of large cities in the proeess of China＇s urbanization and the relative decline of small and medium-sized cities and examines the root causes of such polarization, including the preference of government resource allocation towards political centers and large cities, market effect underlying the self-reinforced agglomeration of large cities, desire of migrant workers to settle in large cities, as well as the lack of government regulation. Regarding the outlook of China＇s urbanization, the paper believes that the appropriate ratio of new urban population absorption should be 30：18：18：34 among mega, large, small and medium-sized cities and designated towns.展开更多
Urban heat environmental quality (UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area. In the last two decades, many researchers from domestic and overseas have stu...Urban heat environmental quality (UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area. In the last two decades, many researchers from domestic and overseas have studied many problems at the aspect of urban heat environment such as urban heat islands, urban air temperature and their relation with urban land cover, city population, air pollution etc. In the recent years, Hangzhou, acting as a center city of Zhejiang Province in China, its urbanization quantum and quantity have both changed greatly, in particular, representing as business affairs building, resident real property and all kinds of specialty market having arisen in built-up zone. Based on Landsat TM images data in 1991 and 1999, urban underlying surface temperature value and Normalized Difference Vegetation Index (NDVI) were calculated using image interpreting and supervised classification technique by remote sensing software ERDAS image 8.4. The relation model between urban underlying surface temperature (UUST) and urban air temperature was setup according to the certain correlation pattern. Reference to the relational standard of assessing human comfort and other meteorology data of Hangzhou City in summer, the spatial distribution characteristic and the spatial variation degree of human comfort of heat environmental quality are estimated and mapped on a middle scale, that is, in six districts of Hangzhou City . Then the paper reveals the main characteristic of spatial variation from 1991 to 1999. Lastly, the change mechanism is analyzed and discussed from the viewpoint of city planning, construction and environmental protection.展开更多
Japan＇s aging rate has exceeded 26%, ahead of any other country in the world. Aging is progressing rapidly in both rural and urban areas. Recently, super-aging in old suburbs is remarkable. Recently, Japanese old sub...Japan＇s aging rate has exceeded 26%, ahead of any other country in the world. Aging is progressing rapidly in both rural and urban areas. Recently, super-aging in old suburbs is remarkable. Recently, Japanese old suburban housing estates are declining. They are facing several serious problems. Most serious problems are aging of residents and decreasing population, and these are caused by long-term dwelling. Because many Japanese think that ＂Japanese Dream＂ is occupancy of detached house in suburb. Japanese suburban residents tend to stay after child rearing. And another severe problem is the increasing vacant houses. In this study, the authors try to clarify the conditions of shrinking suburbs in Japanese cities and will introduce some activities for revitalization in suburbs. As for aging of suburban residents, in old housing estates, the first generation of migrants grew older and continued to live in their own house in suburban areas. Furthermore, their children grew up and moved out. These are caused by the failure of town planning, which supplied the same type of houses in short term. Furthermore, increases in vacant houses are seen throughout every old suburban housing estate, and it induces new uneasiness and social troubles and drop in housing price.展开更多
The informal construction sector is unregulated and operates in a risky environment, thus the need for adoption of appropriate risk management strategies for its survival is essential. Therefore, the aim of this study...The informal construction sector is unregulated and operates in a risky environment, thus the need for adoption of appropriate risk management strategies for its survival is essential. Therefore, the aim of this study was to examine methods used in choosing appropriate risk response strategy in informal construction sector in Tanzania. The study involved construction workers in informal sector in Dar es Salaam and Mwanza in Tanzania. Dar es Salaam and Mwanza are among big cities in Tanzania having more informal construction workers. Questionnaires were prepared in English, translated in Kiswahili and administered by research assistants on informal construction workers. Workers were purposively selected. Out of 1,000 questionnaires distributed 849 questionnaires were fairly filled equating to 84.9%. The collected data was coded and analysed using descriptive statistics mainly frequencies cross tabulation and Chi-square tests. The study established that majority of informal construction workers choose risk response strategies by using common sense followed by previous experience. Within the location, the methods significantly differ whereby Dar es Salaam was dominated by common sense and Mwanza dominated by previous experience. Likewise, use of common sense among respondents was significantly different between gender, age group, level of education and experience. This implies that apart from formal process of choosing risk response strategies, the informal construction sector has its own surviving strategies. The issue of location, gender and experience are essential for risk management in informal construction sector.展开更多
There is a broad recognition that microclimatic conditions contribute to the quality of life in cities. A favorable microclimate has a positive influence on both commercial and social activities. The aim of this study...There is a broad recognition that microclimatic conditions contribute to the quality of life in cities. A favorable microclimate has a positive influence on both commercial and social activities. The aim of this study is to investigate the relationship between the human being and the surrounding thermal environment in terms of thermal acceptability, physical quality of the place, emotional state and the usage of the urban space in hot dry Damascus, Syria. The study is based on questionnaire surveys during the summer and winter in six locations with different microclimates. It is shown that the urban design plays a significant role in improving the microclimate, especially during the summer. The study also illustrates that when people＇s thermal perception is within the thermally acceptable range （i.e., slightly cool, comfortable and slightly warm） they experience the urban design as significantly more beautiful and more pleasant than during thermally unacceptable conditions. The results indicate that there is an interactive relationship between the urban design and humans＇ emotional state. Our findings suggest that a new perspective is needed for determining urban microclimate requirements and incorporating them into the urban design process to enhance the thermal environment in outdoor urban spaces in Damascus.展开更多
Constantine is a big city, particular because of its site and history. But it is especially a city that currently polarizes a huge interest from public authorities, researchers, as well as citizens represented by asso...Constantine is a big city, particular because of its site and history. But it is especially a city that currently polarizes a huge interest from public authorities, researchers, as well as citizens represented by associations that are militating to safeguard and promote the city. Making Constantine ＂a regional capital, a metropolis＂ is the ambitious urban project of this city authorities. It is a prestigious project, but at the same time, a double-edged sword. With the emergence of this project, a new conception of the city and its image is induced, the one that conjures new canons of urban modernity, with the whole discourse that sustains it and indicators that materialize it. A new attitude toward the current city of Constantine has emerged, from both the authorities and citizens. The inhabitants are continuing in spite of all to invest their city and do not accept that the natural process of appropriation of space may be stopped indefinitely. The author will try to expose the conflict situationof a changing city inside numerous and varied issues, as well as stakes and challenges.展开更多
基金supported by the Ministry of Construction Project,the research of the Code for urban planning on flood control(GB50XXX-20XX)
文摘China is one of the countries with the most serious flooding disasters.In China,above 70% of big cities,50% of population and 75% of industrial and agricultural output value are distributed in eastern coastal areas with serious flooding.Therefore,enhancement of theoretical study and experience summarization of urban flood control is of great theoretical and practical significance.As economy is developing rapidly,urban scale is expanding fast,and urban flood control stand is promoted.Urban flood control calls for new concept and methods.This paper makes a systematic summarization of concept evolution and advanced methods concerning urban flood control at home and abroad.The concept of urban flood control has transformed from simple flood control and drainage to coexistence with and use of flood.Flood control measures have transferred form emphasis upon engineering ones to priority to both engineering and non-engineering ones,with special attention to ecological flood control,such as making full use of ecological revetment,ecological realignment of a river,multi-objective management of urban flood detention region,turning flood into resources and utilization of wetlands.
文摘This paper provides an analysis of the rapid expansion in number and population of large cities in the proeess of China＇s urbanization and the relative decline of small and medium-sized cities and examines the root causes of such polarization, including the preference of government resource allocation towards political centers and large cities, market effect underlying the self-reinforced agglomeration of large cities, desire of migrant workers to settle in large cities, as well as the lack of government regulation. Regarding the outlook of China＇s urbanization, the paper believes that the appropriate ratio of new urban population absorption should be 30：18：18：34 among mega, large, small and medium-sized cities and designated towns.
基金Under the auspices of the National Natural Science Foundation of China (No.40001008).
文摘Urban heat environmental quality (UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area. In the last two decades, many researchers from domestic and overseas have studied many problems at the aspect of urban heat environment such as urban heat islands, urban air temperature and their relation with urban land cover, city population, air pollution etc. In the recent years, Hangzhou, acting as a center city of Zhejiang Province in China, its urbanization quantum and quantity have both changed greatly, in particular, representing as business affairs building, resident real property and all kinds of specialty market having arisen in built-up zone. Based on Landsat TM images data in 1991 and 1999, urban underlying surface temperature value and Normalized Difference Vegetation Index (NDVI) were calculated using image interpreting and supervised classification technique by remote sensing software ERDAS image 8.4. The relation model between urban underlying surface temperature (UUST) and urban air temperature was setup according to the certain correlation pattern. Reference to the relational standard of assessing human comfort and other meteorology data of Hangzhou City in summer, the spatial distribution characteristic and the spatial variation degree of human comfort of heat environmental quality are estimated and mapped on a middle scale, that is, in six districts of Hangzhou City . Then the paper reveals the main characteristic of spatial variation from 1991 to 1999. Lastly, the change mechanism is analyzed and discussed from the viewpoint of city planning, construction and environmental protection.
文摘Japan＇s aging rate has exceeded 26%, ahead of any other country in the world. Aging is progressing rapidly in both rural and urban areas. Recently, super-aging in old suburbs is remarkable. Recently, Japanese old suburban housing estates are declining. They are facing several serious problems. Most serious problems are aging of residents and decreasing population, and these are caused by long-term dwelling. Because many Japanese think that ＂Japanese Dream＂ is occupancy of detached house in suburb. Japanese suburban residents tend to stay after child rearing. And another severe problem is the increasing vacant houses. In this study, the authors try to clarify the conditions of shrinking suburbs in Japanese cities and will introduce some activities for revitalization in suburbs. As for aging of suburban residents, in old housing estates, the first generation of migrants grew older and continued to live in their own house in suburban areas. Furthermore, their children grew up and moved out. These are caused by the failure of town planning, which supplied the same type of houses in short term. Furthermore, increases in vacant houses are seen throughout every old suburban housing estate, and it induces new uneasiness and social troubles and drop in housing price.
文摘The informal construction sector is unregulated and operates in a risky environment, thus the need for adoption of appropriate risk management strategies for its survival is essential. Therefore, the aim of this study was to examine methods used in choosing appropriate risk response strategy in informal construction sector in Tanzania. The study involved construction workers in informal sector in Dar es Salaam and Mwanza in Tanzania. Dar es Salaam and Mwanza are among big cities in Tanzania having more informal construction workers. Questionnaires were prepared in English, translated in Kiswahili and administered by research assistants on informal construction workers. Workers were purposively selected. Out of 1,000 questionnaires distributed 849 questionnaires were fairly filled equating to 84.9%. The collected data was coded and analysed using descriptive statistics mainly frequencies cross tabulation and Chi-square tests. The study established that majority of informal construction workers choose risk response strategies by using common sense followed by previous experience. Within the location, the methods significantly differ whereby Dar es Salaam was dominated by common sense and Mwanza dominated by previous experience. Likewise, use of common sense among respondents was significantly different between gender, age group, level of education and experience. This implies that apart from formal process of choosing risk response strategies, the informal construction sector has its own surviving strategies. The issue of location, gender and experience are essential for risk management in informal construction sector.
文摘There is a broad recognition that microclimatic conditions contribute to the quality of life in cities. A favorable microclimate has a positive influence on both commercial and social activities. The aim of this study is to investigate the relationship between the human being and the surrounding thermal environment in terms of thermal acceptability, physical quality of the place, emotional state and the usage of the urban space in hot dry Damascus, Syria. The study is based on questionnaire surveys during the summer and winter in six locations with different microclimates. It is shown that the urban design plays a significant role in improving the microclimate, especially during the summer. The study also illustrates that when people＇s thermal perception is within the thermally acceptable range （i.e., slightly cool, comfortable and slightly warm） they experience the urban design as significantly more beautiful and more pleasant than during thermally unacceptable conditions. The results indicate that there is an interactive relationship between the urban design and humans＇ emotional state. Our findings suggest that a new perspective is needed for determining urban microclimate requirements and incorporating them into the urban design process to enhance the thermal environment in outdoor urban spaces in Damascus.
文摘Constantine is a big city, particular because of its site and history. But it is especially a city that currently polarizes a huge interest from public authorities, researchers, as well as citizens represented by associations that are militating to safeguard and promote the city. Making Constantine ＂a regional capital, a metropolis＂ is the ambitious urban project of this city authorities. It is a prestigious project, but at the same time, a double-edged sword. With the emergence of this project, a new conception of the city and its image is induced, the one that conjures new canons of urban modernity, with the whole discourse that sustains it and indicators that materialize it. A new attitude toward the current city of Constantine has emerged, from both the authorities and citizens. The inhabitants are continuing in spite of all to invest their city and do not accept that the natural process of appropriation of space may be stopped indefinitely. The author will try to expose the conflict situationof a changing city inside numerous and varied issues, as well as stakes and challenges.
