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991.
As the rent-free compound housing system in Ghana gradually became unpopular, there was the need for state intervention in housing provision. Housing became an important part of the country’s developmental policies through state interventions prior to the late 1970s. The economic crises in 1979 forced the country to opt for Structural Adjustment Programme, compelling the state to relax on its efforts to provide housing for the public. The paper uses the mode of economic integration framework to discuss the various housing forms in the country. It argues, housing provision led by the private sector creates remarked differences between housing for the higher and lower income groups. The study uses two low income communities in Accra to explain different ways by which the urban poor in Ghana accommodate themselves amidst the country’s housing problems. The study concludes there is an alternative to the housing crises in the country which could be found in the public-private investments in the rental form of the compound housing system.  相似文献   
992.
Increase in waste generation calls for an effective waste management as this has become a necessity for environmental sustainability. Several methods are adopted in managing waste, which include waste reduction, reuse, thermal treatment, recycling and landfilling. The landfill method is recognised as the most used of all the waste management methods in developing countries such as Ghana. However, the selection of a suitable landfill site is very difficult and tedious. This is because it involves a consideration of many factors such as environmental, topographic, economic, socio-cultural and civil engineering. This research sought to identify a suitable landfill site by applying GIS multicriteria and weighted overlay approach in the Bongo District of Northern Ghana. The analysis relied on criteria and weights provided by the technocrats and the indigenes in the district as a way of demonstrating how landfill siting impasse can be resolved by incorporating the various stakeholders. The results obtained provided clear areas for landfill sites in the study area from the technocratic and the indigenous perspectives. However, the technocratic perspective failed to include an important cultural criterion, sacred groves, as a factor. The indigenous perspective also compromised on the factor related to nearness to residential areas, and is equally not sufficient on its own. The optimal landfill sites, which meets the expectations of both the technocrats and indigenes, was identified. This perspective has produced technically favourable and socio-culturally acceptable landfill site. However, it is recommended an environmental impact assessment (EIA) be conducted to identify the full environmental and social cost of the site. It is concluded that in landfill site selection much attention be given to cultural factors in the same way as the technical factors.  相似文献   
993.
Urban densification trends combined with redevelopment increasingly moving away from large former industrial and transport sites toward existing town centres and corridors indicate redevelopment is becoming increasingly complex, difficult to plan for and undertake. The interplay between land and property markets and planning frameworks suggest city planners and urban researchers need new tools and methodologies to gain insights into ways to deliver effective responses. Despite the need, there is a limited availability of comprehensive models to fulfil the task. This paper describes a GIS-based tool to assess parcel-level financial feasibility and housing supply associated with urban redevelopment within a precinct. The tool incorporates existing and potential built form and parameters associated with the planning framework and land and property markets. Using a real case study in a workshop, tool performance was evaluated by professional urban planners in terms of its capacity to produce metrics and visualisations of potential scenarios of redevelopment. Results indicate the usefulness of the tool for emulating land market conditions and testing scenarios of planning regulation and market changes for strategic planning purposes.  相似文献   
994.
The research was conducted on the outskirts of Yogyakarta City that administratively include three districts of Sleman Regency, namely Depok, Gamping, and Mlati, and three districts of Bantul Regency, namely Kasihan, Sewon, and Banguntapan. It aimed to obtain a deeper understanding on the perceptions of stakeholders on the regional transformation phenomena occurring on the outskirts of Yogyakarta City. This is a qualitative case study research with a single case. The case study research method was selected because the observed phenomenon is contemporary and the analyzed issue is unique. It used a qualitative method with field observations and in-depth interviews to several informants as data acquisition techniques. The informants were stakeholders from state/government, private sector/entrepreneur, academics, and civil society, which were selected using purposive sampling method. The research data processing and analysis included: (1) data reduction, (2) data presentation, and (3) data conclusion. In order to examine the reliability and validity of the data, the research used source triangulation method. The results showed that all stakeholders perceived the regional transformation on the outskirts of Yogyakarta City to have positive and negative consequences on various dimensions. The positive ones were the economic opportunities, generated by the regional transformation process, for both the native people and the migrants. Aside from these positive consequences, the regional transformation on the outskirts of Yogyakarta City also caused negative impacts on the physical, economic, social, and cultural dimensions of the outskirts.  相似文献   
995.
The economy of the Jammu and Kashmir state depends mostly on traditional forms of occupation. Unaffected and unaltered by modern day industrial developments and changing times, the indigenous traditional occupations of farming, animal husbandry and horticulture forms the backbone of the state economy. But in the last few decades, Agriculture in the state as well as the study area is receiving a set back and Horticulture is flourishing leaps and bounds. The present study aims to analyze various determinants responsible for this change. Climatic as well as field data was thoroughly analyzed to comprehend the situation. A Mann–Kendall test was done on the climatic data to support the hypotheses. It was observed that initially changing climatic trends proved to be the triggering factor supporting this change, but in due course of time, the determinants took an economic and psychological turn. The perusal of Indian Meteorological Data reveals an increasing trend of annual mean maximum temperature from 16.78 °C in 1985 to 17.58 °C in 1995 and an increase from 5.30 °C to 7.00 °C in the annual mean minimum temperature, and as such acting as a triggering factor for the land use conversion. Further, the mean annual rainfall shows a decrease from 100.75 mm in 1981 to 79.43 mm in 1991. The greater economic returns from horticulture as well as the changing behavioral patterns of people over the time further cemented its growth. The farmers have since persisted with the horticulture activity as it has proven to be an economically a much better lucrative enterprise.  相似文献   
996.
Understanding climate variability and change is essential for designing adaptation policies and strategies to deal with the impacts of climate change on the agricultural sector. This Paper aims at assessing climate variability/change, the perception of rural farmers on climate change and preferred  adaptation strategies among the farmers in some selected farming communities in Nigeria. The study thus used both meteorology data and social survey, to examine variability/change in climate and factors determining the adaptation techniques adopts by rural farmers. The results show a relatively uniform temperatures and some seasonal variations in recent years (diurnal range of temperature is about 10 °C) but the rainfall shows much more seasonal variations. The rainfall has relatively undeviating trend from 1981 to 1996 but the trend appears to be upwards from the year 1997 to 2010. About 72.8% participants responded in the affirmative that climate is changing but there appears to be a significant relationship between the length of farming experiences and farmers’ perceptions of climate change adaptation techniques. Water-related (about 53%) and nutrient related (about 52%) technologies appear to have a high preference among the farmers. The major driver that determines farmers’ preference for climate change adaptation techniques is their incomes and experiences.  相似文献   
997.
Spatial and temporal trends of dust storms across desert regions of Iran   总被引:1,自引:1,他引:0  
Dust storms are among natural and anthropogenic hazards for socioeconomic resources, especially in desert regions. In recent years, dust storms have become a serious problem, especially in desert regions of Iran. This study investigates temporal and spatial variation of dust storm frequency in desert regions of Iran. The number of dusty days (NDD) are collected from 22 stations across the region. The statistical analysis of NDD time series is carried out to show both spatial and seasonal pattern of dust storm occurrence in the region. The regional map of statistical characteristics indicates a north to south increasing dust storm frequency. The spatial map also reveals higher year-to-year variation in south eastern Iran. The seasonality of NDD shows the highest frequency for summer followed by the spring and autumn seasons. The popular Mann–Kendall and the bootstrap MK test to consider serial correlation are then applied for Trend assessment. Results showed both negative (across the north and northwestern regions) and positive trend (across south and south eastern regions) in the annual and seasonal NDD time series. This north-to-south gradient in the spatial and temporal frequency NDD may arise from harsh dry and gusty winds as well as intense land use change in the south eastern territories of Iran. However, more careful and detailed studies are required to connect environmental conditions to change in NDD frequency.  相似文献   
998.
Windblown dust originating in China and Mongolia causes health effects and agricultural damage in its source areas and causes Asian dust events in Japan. An early warning system that could be combined with weather forecasts would be helpful in preventing serious damage. However, it is difficult to specify source areas of dust with current dust modeling systems because land surface information, including vegetation coverage and land surface soil water content, is inadequate. To find and monitor dust source regions, a semi-real-time dust erodibility map was developed based on MODIS satellite data that focuses particularly on the threshold wind speed in a target area of northeast Asia including China and Mongolia (35°–50°N, 75°–120°E). The mapping system incorporates satellite data on snow cover, areas of frozen soil, surface soil water content, and vegetation cover.  相似文献   
999.
The paper discusses a model which predicts the trajectory of floating rigid bodies and may be applied to compute the motion of woody “debris” mobilized during floods. The model couples a Discrete Element (DE) Lagrangian approach for the calculation of motion of rigid bodies with the Eulerian solution of the shallow water equations (SWE), in order to simulate the transport of a cylinder in a two-dimensional stream. It differs from existing models since it is based on a dynamic approach, adapting the Basset–Boussinesq–Oseen equation. In a first step, forces are computed from flow and log velocities; then, the equations of dynamics are solved to model the planar roto-translation of the body. Model results and physical reliability are clearly affected by the values of the drag and side coefficients, especially since logs, modelled as cylinders, are able to change their orientation towards the flow. Experimental studies to evaluate drag and side coefficients can be found in the literature for a submerged cylinder, with various orientations. To extend such results to the case of a floating log, the authors performed a series of laboratory tests on partially submerged cylinders, implementing the outcomes in the proposed DE-SWE model. The coupled model is validated against existing laboratory data concerning spheres and wooden cylinder transport.  相似文献   
1000.
Mining exploitation has a negative impact on the natural environment. Voids created in the rockmass result in displacements and deformations of land surface. During planning and conducting the exploitation, the range of exploitation influence in the form of linear deformations is being determined. On the basis of mining-geological parameters of exploitation, the exploitation range of influences is calculated. According to the literature, many different ranges of exploitation influences can be determined depending on what has been the purpose of it. Different types of exploitation influence ranges can be distinguished, such as theoretical, damage or measurable. In the paper, the matters connected with determining those three types of the influence range are taken under consideration. The comparison of magnitudes of determined influence ranges is illustrated with two practical examples.  相似文献   
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