Population density pattern and change in the City of Riyadh,Saudi Arabia

This paper examines and assesses changes in the population density pattern in the city of Riyadh, the capital of Saudi Arabia where the city has undergone dramatic changes in its physical as well as its social structure. Analysis of data revealed a decline in population density at an exponential rate from the city center with variation between city sectors and zones. The city's rapid horizontal expansion and dispersal of population is the result of factors such as increases in city population and in size and number of single family dwellings, widing of streets, rise in income and residential mobility rates, mass use of automobile, change in family size, zoning regulations, leapfrogging, and huge governmental city development projects. The resulting low population density pattern made it difficult for city officials to provide necessary services and facilities for the dispersed residential development. This paper recommends that city officials make real efforts and workable programs to stop or slow this uneconomical growth by improving quality of life in the central areas to make them residentially desirable by some city residents and reduce the high residential turnover the central area has experienced in last years, and to centralize peripheral growth by planning for self-sufficient satellite communities in outer areas.     

Changes in coastal land use and the reasons for selecting places to live in Banda Aceh 10 years after the 2004 Indian Ocean tsunami

Ten years after the Indian Ocean tsunami in 2004 and following a long process of rehabilitation and reconstruction, Aceh has finally recovered. After the tsunami, Aceh experienced a dramatic migration of its coastal population away from the city; however, after 10 years, the population has mostly recovered. As new houses have been built and new economic activities commenced in the coastal areas, there is now concern regarding potential future tsunami risks for the city. The initial rehabilitation and reconstruction plan sought to prevent the construction of any new houses 500 m from the coastline; however, this failed to happen. This paper elucidates the reasons why these new coastal communities chose their new housing areas and examines the coastal land use changes around Banda Aceh 10 years after the Indian Ocean tsunami. Questionnaires were distributed to 457 respondents, and multiple logistic regressions were used to examine the reasons for household location selection and whether a possible future tsunami was a deciding factor. To examine the coastal land use changes, a series of aerial images from the Banda Aceh coastal area were digitised. It was found that tsunami history was not a major factor in new household selection; rather, rents and land prices, distance from work, and family connections were the top three reasons motivating households to select new living places. These changes and new settlements have given the city’s disaster management agency the challenge of building more emergency infrastructure in the coastal areas.     

New populations in the British city centre: Evidence of social change from the census and household surveys

Encouraged by government policies to promote city centre living and to increase residential land use on brownfield sites, there has been considerable repopulation of the city centre. Through detailed small-area census analysis of Birmingham, Bristol, Cardiff and Swansea, supplemented by household surveys and key informant interviews, the research points to a range of population characteristics and changes occurring in the British city centre. Certain characteristics such as a high proportion of lone person households, fewer children and low car ownership remain fairly consistent. However, substantial population expansion affirms that a large part of the population is “new”. Between 1991 and 2001, men came to outnumber women, and each of the city centres saw a relative expansion of its young adult population. The new residents have a higher appreciation than longer term residents of proximity to work and leisure facilities, and of the stylishness of city centre living. Most of the new residents rent their accommodation, generally in flats, and the predominance of renting is associated with a transient attitude to city centre residence among the new population. Socio-economic evidence indicates a striking rise in social status or gentrification in all the city centres investigated, especially where high status private housing developments encourage the trend. With policies promoting residential development, the city centre is becoming increasingly socially exclusive.     

安徽省建设用地现状及变化趋势和特点

揭示安徽省各类建设用地存量和人均情况及闲、空、批而未用情况;阐述近八年来建设用地扩展情况和时空分布特点;着重分析人均用地与城市规模、人口密度、经济水平、自然条件的关系以及建设用地的内部结构。     

Brackish groundwater as an alternative source of cooling water for nuclear power plants in Israel

Because of a high population density in the coastal plain, any future nuclear power plants will be located in the sparsely settled Negev desert Since this part of Israel has no surface water, the only alternatives to cooling water are piped-in Mediterranean. Water and local, brackish groundwater One particular aquifier was examined for its potential to provide the required amount of cooling water over the lifetime of the plant, without causing a drastic lowering of the regional water table It was concluded that given the assumed range of aquifer properties, extraction of brackish water for cooling purposes will not result in large changes in the regional water table, furthermore, it could possibly halt the gradual deterioration of the quality of the water supply of the city of Beer Sheva     

空心化村庄成因及治理对策探析——以江苏省邳州市前湖村为例

以邳州市前湖村为例,在逐户调研的基础上,分析其空心化现状,并从法律制度、政府倾向、人口结构、自然历史条件和经济条件五方面探讨村庄空心化成因,进而提出前湖村的整治模式和治理对策,以期为空心化村庄规划整治提供借鉴。     

南昌市2010年规划中心城区建筑密度遥感研究

论述了南昌市建筑密度调查的技术方法，阐明了城市建筑密度的现状分布和分区，分析了建筑密度对 城市发展的影响，探讨了城市规划中存在的问题和对策。     

Ethno-ideological segregation and metropolitan development

The effect of ethnic residential segregation on metropolitan development and expansion is examined. The ethno-ideologically divided city is an extreme case of segregation and Jerusalem, an example of such a city, provides a good case study. Deviations from patterns of population change predicted by the theory of the urban population density gradient are analysed non-statistically using the available data. When the two ethnic sectors are treated as separate cities, these deviations do not seem to be very important and population change conforms to the model. This seen in the light of local patterns of segregation seems to imply that at the local ‘tactical’ level domination and exclusion of the other group seems to result, whereas on the regional strategic level power is shared more equally and economic and demographic factors play the major role in fashioning the distribution of population change.     

Spatial development,density gradients and their planning implications: The Rome case

Like urban space population density patterns are constantly changing. While Newling observed four stages of density gradients from youthful through mature and old stages of a city, this study shows that Rome was not a youthful city at the end of the 19th century yet Newling's youthful stage density gradients were prevalent at that time. In the 20th century, like Newling's later stages Rome also showed depopulation of the center leading to a crater-like density gradient. City planning policies were only partially responsible for patterning the density over the century. Though Newling's model is not applicable in the 19th century Rome, it is largely valid when automobiles were introduced.     

临汾市近期人口变化趋势研究

采用人口密度、人口广狭度、人口集中、分散度对临汾市1990、2000、2008年间人口分布现状、人口分布变化极其变化的原因进行了分析研究,结果表明:近20年来临汾市的人口分布变化极大地受临汾市社会、经济因素的影响,不断向中部平川地区集中,而且今后还将继续沿着这一方向发展.     

Assessment of urban groundwater heat contaminant in Jakarta, Indonesia

Urbanization has become one of the domain processes for city development in Indonesia. The results of the extremely high densities of fast growing population have led to negative subsurface environmental impact. Jakarta, as one of the rapidly developed and urbanized cities in Southeast Asia, has become one of the interesting urbanization city to analyze its effects. In Jakarta, the use of groundwater has greatly accelerated conforming to the rise in its population and the development of the industrial sector, which consume a relatively large amount of water. The increase of groundwater exploitation in Jakarta city has already caused a negative impact on these resources. Therefore, an assessment of groundwater trends in the urban area, including their hazard and risk management, is a necessary action. This paper describes the assessment of urban groundwater loading caused by human concentration in Jakarta city. Subsurface heat contamination under the condition of surface warming shows significant effects of urban groundwater loading during the past century in Jakarta city.     

城区水文循环机制与改善策略分析

在城区化过程中,由于人口快速成长且集中,随之而来的建筑物、道路等不透水面密度增加,导致地下水补给减少及破坏水文循环。为了解土地利用方式改变对长期水文量影响,建立一个适宜的城区水循环模式是非常重要的。选定台湾台北的六馆抽水站集水区进行分析,模式参数经过敏感度分析、率定与验证。采用改变不同透水铺面设置比例的方案,评估其对径流量、入渗量、蒸发散量的改变。并分析设置不同比例屋顶雨水贮集系统对地表径流量及供水量的改变。所建立的城区水循环模式是评估土地利用改变造成水文量的改变的一个有效工具,并可提供决策者做为城区土地利用决策的参考。     

Assessing the resilience of Delhi to climate-related disasters: a comprehensive approach

The study addresses disaster risks in Delhi through a resilience approach. It utilizes the Climate Disaster Resilience Index (CDRI) tool, which assesses disaster resilience from five dimensions: physical, social, economic, institutional, and natural. Each dimension comprises 5 parameters, and each parameter consists of 5 variables. The study is carried out in the nine revenue districts of Delhi and reveals that East Delhi is least resilient and New Delhi is most resilient. The CDRI analysis in East Delhi points out the urgent need to focus on key parameters such as housing and land use, population, intensity and frequency of natural hazards, ecosystem services, and land use in natural terms. On the other hand, New Delhi is the most resilient due to all five dimensions, where most significant parameters responsible for its high resilience are housing and land use, population, income, employment, intensity and frequency of natural hazards, ecosystem services, and land use in natural terms. In addition, the overall results of all nine districts show an inverse relationship between resilience score and population density. For example, districts with higher population density show low resilience and vice versa. Moreover, districts located on hazard-prone areas show low resilience. For example, East Delhi and North East Delhi scored low resilience because they both are situated on the Yamuna flood catchment areas. The study further develops key suggestions that are required to address disaster risk in all nine districts of Delhi and discusses future implications of CDRI to address city??s vulnerability. The approach??s distinctness is reflected through its consideration of micro-level diversities and presents some implications to resilience.     

基于大数据的上海市人居环境适宜性评价

人居环境是居民生活和社会发展的重要基础,科学量化人居环境适宜性有助于引导区域人口规划,促进人口与资源协调发展。本文基于大数据,运用GIS技术,从居住环境、社会环境、经济环境和生态环境四个方面构建综合评价指标体系,以1 km栅格为基本单元,对上海市人居环境适宜性进行空间测度评价。结果表明:上海市人居环境指数介于-1.79~45.57之间,空间分布上呈现中心城区向周边区域递减的态势,整体分布趋势与人口密度相关性较高。高值区主要集中在中心城区一带,土地面积较小,人口密度大,承载压力较大;发展潜力较高的中等适宜区主要涉及外环及新城区域,土地面积大,是未来人口导向的潜力区。     

混合热源与热泵联动空调技术及其在天津"975"工程中的应用

混合热源与热泵联动空调技术以天然、廉价和低品位的资源为主,以高品位资源为尖峰负荷的系统能源配置设计新方法,实现以单投入多功能的新型能源利用方式替代多投入单功能传统的能源利用方式,使建筑物的空调系统具有经济、节能与环保等特点.该项技术能较好地应用于能源获取难度大、单一冷热源不能满足要求的工程.在天津"975"工程供暖及制冷系统中的应用结果表明:混合热源与热泵联动空调技术成功地解决了系统的冷热源、热(冷)负荷需求大等难题,具有明显的环境与经济效益.     

Assessment of land-use change and its impact on the environment using GIS techniques: a case of Kolkata Municipal Corporation,West Bengal,India

It is axiomatically true that urbanization in India's metropolises and large cities has been exacerbated since the beginning of the millennium, consuming the natural and semi-natural ecosystem on the outskirts of the city, resulting in a zone with a distinct climate known as urban climate. Such a climate—the result of a built-up environment is distinctly different from the natural climate as the paved surface and concrete skyscrapers not only destroy the natural ecosystem, it peculiarly induce a different kind of insolation, cooling and air drainage were lacking in green space, water bodies and open space cannot accommodate with environmental rhythm properly, resulting into the accumulation of heat, ecological derangement of subsurface soil which can easily be predicted by GIS analysis. This paper is an attempt to measure urban growth and its impact on the environment in the metropolitan city Kolkata. The use of satellite data and GIS techniques to detect urban expansion is a highly scientific strategy. Using geospatial techniques, the current study attempts to examine major urban changes in Kolkata and its surroundings from 1988 to 2021. Landsat 5 TM and Landsat 8 OLI temporal data are used to identify land-use change through unsupervised classification; Spectral Radiance Model and Split Window Algorithm method are used for identifying land surface temperature change. SRTM DEM (30 m) has been used to identify flood risk zones and several spectral indices like Normalized Difference Vegetation Index and Modified Normalized Difference Water Index are a further extension for environmental assessment. By all such suitable methods, a clearer change in an urban environment is detected within the period of 33 years (1988–2021). The result shows that the population changes, vegetation cover and built-up area, and accessibility are at a rapid rate. These changes are causing major environmental degradation in the city. The classification result indicates that appropriate land use planning and environmental monitoring are required for the long-term exploitation of these resources.

     

青岛核心城区饱和负荷预测研究

本文以青岛市经济社会发展现状为基础,结合城市发展定位和发展规划,分别采用基于人口容量的特征参数类比法、饱和负荷密度特征参数类比法以及空间负荷预测法,对青岛市核心城区饱和负荷进行了预测,为确定城市电网最终规模,并在核心城区用地中为电力可持续发展预留必要的空间提供依据。     

城市人口分布空间自相关的功率谱分析

从理论上可以证明标准的城市人口密度负指数距离衰减模型本质上是一种空间相关函数,基于这种思想对Clark模型进行Fourier变换,可以导出城市人口密度的幂次频谱分布,且功率谱指数理应为β=2±。负指数与幂指数的这种变换关系暗示了城市地理系统简单与复杂的辩证关系。借助中国杭州市4年的人口普查资料转换的平均人口密度分布数据对上述推论进行检验,发现β渐进式趋近于2但并不约等于2。将β值进一步换算为人口过程的分维D和Hurst指数H,结果表明：城市人口具有长程负相关作用,但这种空间作用显示明确的局域化倾向。目前的城市形态演化模拟几乎无一例外地引入了长程作用,根据杭州人口分布的局域化特征,有关地理长程作用的假设和应用有必要重新探讨。     

Strategies for addressing climate change on the industrial level: affecting factors to CO2 emissions of energy-intensive industries in China

Urban earthquake disaster prevention is regarded as an integrated systematic engineering. Urban earthquake disaster prevention system is made up of all the earthquake disaster prevention activities. The concept and composition of urban earthquake disaster prevention system periphery were presented based on system periphery theory. A seismic risk-control mechanism model of system periphery was deduced using exchange rate of periphery as a dependent variable, and an observability–controllability model of system periphery was established and crystallized in its application to the quantitative analysis of practice problem. The input sets of urban earthquake disaster prevention system are determined as the maximum earthquake magnitude happened in or around the city, the measurable earthquake frequency, population density and fixed assets density. The inside state sets of urban earthquake disaster prevention system are determined as disaster resistant ability of buildings, disaster resistant ability of lifelines and investment dynamics in disaster prevention per urban built-up area. The system output is urban seismic risk. The calculative results show the model presented in this study can analyze the influence of system periphery intensity and inside state on seismic risk and can control urban seismic risk by adjusting the parameters of system periphery, the system inside state and human influence intensity.     

Heat risk assessment based on mobile phone data: case study of Bratislava,Slovakia

The aim of this interdisciplinary study is to assess the heat risk for Bratislava. The following layers were created to compute the risk index: the hazard layer of air temperature, a mitigation layer of tree vegetation, an exposure layer of population and a vulnerability layer of individuals over 65 years of age. The MUKLIMO_3 model was used to evaluate the field of mean surface air temperature at 9 PM during selected days of the summer heat wave in August 2018. The tree vegetation layer, in the form of percentage per grid cell, was derived from Sentinel-2 satellite data. Population density data are based on mobile positioning data, and elderly population data are based on a gridded database from the statistical census. Input layers were unified into a resolution of 500 × 500 m, and the heat risk index was calculated by summation of the weighted input layers. The results reflect the variability of the population and the elderly population within the city, as well as the variability of the temperature field, which is caused by the joint effect of an urban heat island and topography. The highest values of risk index occur within the broader city centre, with specific hot spots at several places.