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1.
Nourani Vahid Elkiran Gozen Abdullahi Jazuli Tahsin Ala 《Natural Resources Research》2019,28(4):1217-1238
Natural Resources Research - Solar radiation data are crucial for the design and evaluation of solar energy systems, climatic studies, water resources management, estimating crop productivity, etc.... 相似文献
2.
In recent decades, attaining urban sustainability is the primary goal for urban planners and decision makers. Among various aspects of urban sustainability, environmental protection such as agricultural and forest conservations is very important in tropical countries like Malaysia. In this regard, compact urban development due to high density, rural development containment is known as the most sustainable urban forms. This paper attempts to propose an integrated modeling approach to predict the future land use changes by considering city compactness paradigms. First, the cellular automata (CA) were applied for calculating land use conversion. Next, weights-of-evidence (WoE) which is based on Bayes theory was utilized to calibrate CA model and to support the transitional rule assessment. Several urban-related parameters as well as compact city indicators were utilized to estimate the future land use maps. The results showed how compact development parameters and site characteristics can be combined using the WoE model to predict the probability of land use changes. The modeling approach supports the essential logic of probabilistic methods and indicates that spatial autocorrelation of various land use types and accessibility is the main drivers of urban land use changes. 相似文献
3.
Changes in Geomorphic characteristics in the lower reaches of the Gongola River channel following construction of Kiri dam have been investigated. The study focused on changes in the channel bankfull width and of riverbed width after the control of the river flow, variation in discharge characteristics between pre- and post- dam periods and the impact of discharge variation on post- dam river channel. Results of the analysis revealed that the main effect of the impoundment of the Gongola channel is a drastic decrease in flood peaks below the reservoir by 11.5% (from 1,420 m3/sec to 1,256 m3/sec). The low flows have on the other hand increased by 268% (from 5.7 m3/sec to 21 m3/sec). The resultant effect of decrease in the discharge was reduction in the channel bankfull and riverbed widths by 38.3% and 72.2% respectively. Also, the post- dam channel became less sinuous and braided in some of the reaches downstream. Discharges of high peaks were found during the period of maximum precipitation (June to September) whereas low discharges were recorded during the period of minimum or no precipitation (December to May). Some of the observed implications of the flow control on the geometric variables were reduction in the overall channel width, concave bank erosion and emergence of vegetation in some of the reaches. 相似文献
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After the fall of the Mengistu regime in 1991 the extreme south of Ethiopia first went through a period of relative peace in spite, or because of, the total absence of state institutions. The structures of local societies, among them thegada or generation set system, and the local forms of food production appeared to be sufficient for the needs of the local population. Then a variety of parties and liberation fronts started to compete for the control of state institutions which were expected to reappear. This led to a local war in which group identities were re-drawn to fit the patterns of ethnic movements or micro nationalisms. The paper examines primarily the examples of Oromo and Somali identity in this context. 相似文献
6.
Surface electrical and electromagnetic surveys were conducted on top of a solid waste facility in Unguwan Dosa, Kaduna State,
Northwest Nigeria. The aim of the geophysical survey was to detect vertical and subvertical fractures that may provide pathways
for groundwater and contaminant transport. Results from the 2D electrical resistivity imaging showed vertical and subvertical
contacts overlain by 6–10 m thick overburden. Quantitative interpretation of the VLF-EM data correlates well with the results
of the 2D resistivity imaging delineating the vertical and subvertical contacts as good and weak conductors (fractures zones)
with resistivity values of 40–220 and 300–420 Ω m, respectively. Azimuthal Schlumberger VES measurements yield apparent anisotropy
values ranging from 1.01 to 1.47 for electrode spacings of 1–45 m with the highest value recorded at spacing of 2 m. However,
azimuthal variations at large spacings (30–45 m) showed no fracture anisotropy due possibly to the array’s low sensitivity
to anisotropy at these spacings. The result of the study showed that pollutants in the leachate can reach and contaminate
the groundwater. Therefore, urgency for leachate treatment at this site is recommended to prevent contamination of groundwater. 相似文献
7.
Due to the population growth and continuous migration of people from rural areas to urban areas, it is important to identify the suitable locations for future development in order to find suitable sites for various kinds of facilities such as schools, hospital and fire stations for new and existing urban areas. Site suitability modelling is a complex process involving various kinds of objectives and issues. Such a complex process includes spatial analysis, use of several decision support tools such as high-spatial resolution remotely sensed data, geographical information system (GIS) and multi criteria analysis (MCA) such as analytical hierarchy process (AHP), and in some cases, prediction techniques like cellular automata (CA) or artificial neural networks (ANN). This paper presents a comparison between the results of AHP and the ordinary least square (OLS) evaluation model, based on various criteria, to select suitable sites for new hospitals in Qazvin city, Iran. Based on the obtained results, proximity to populated areas (0.3) and distance to air polluted areas (0.23–0.26) were the two highest important criteria with high weight value. The results show that these two techniques not only have similarity in size (in m2) for each suitability class but they also have similarity in spatial distribution of each class in the entire study area. Based on calculations of both techniques, 1–2%, 25%, 40–43%, 16–20% and 14% of study areas are assigned as ‘not suitable', ‘less suitable', ‘moderately suitable', ‘suitable' and ‘most suitable' areas for construction of new hospitals. Results revealed that a 75% similarity was found in the distribution of suitability classes in Qazvin city using both techniques. Nineteen per cent (19%) of the study area are assigned as ‘suitable' and ‘most suitable' by both methods, so these areas can be considered as safe or secure areas for clinical purposes. Moreover, almost all (99.8%) suitable areas are located in district 3, because of its higher population, less numbers of existing hospitals and large numbers of barren land plots of acceptable size. 相似文献
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The physically disabled persons represent a special group of the transportation disadvantaged who have suffered many deprivations. The study explores the travel patterns and some of the challenges being encountered by the physically disabled in Jos, Nigeria. Using the questionnaire and focus group discussion methods, the study found that the respondents are of low social and economic statuses. Walking, with enormous time and energy costs, is the most common means of travel among the group. Commercial vehicle drivers apparently hardly attend to the transportation needs of the group even when they can afford the fare. The physically disabled persons view this “injustice” as a reflection of a whole gamut of perceived discriminatory policies of the “able” society to isolate and disempower them. There is therefore a deep-seated feeling of resentment among the physically disabled towards society’s perceived apathy, marginalization and discrimination that manifest even in access to transportation. They believe that the social and physical environments are deliberately hostile to them. Any plans to alleviate the transportation problems of the disabled and integrate them into the mainstream of the economic and social activities of the larger society should address, fundamentally, these perceived marginalization and injustices. 相似文献
9.
Abdullahi Osman El-Tom 《GeoJournal》1998,46(2):155-161
Focusing on the Berti of Sudan, this article assesses the role of Islam and Arabism as important variables in the social construction
of cultural identity of the studied people. In line with most relevant recent literature, the author looks at cultural identity
as a social construct, a dynamic ideology of shifting borders and a historical process that is grounded on diachronic social
formation. The article argues that the present Berti identity is a conscious reflection of their subordinate position vis-à-vis
the kingdoms and states which have dominated Sudan over the past few centuries.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Abdullahi Osman El-Tom 《GeoJournal》1998,46(2):163-170
This article assesses the state of female circumcision in the Sudan with the primary emphasis being placed on the Berti of
Darfur. Among other things, the article examines the factors that have so far led to the perpetuation of the practice and
the failure of the anti-circumcision campaign. The author suggests a renewal of the campaign through the use of a comprehensive
approach which encompasses the social, aesthetic, medical, identificational and religious variables involved in the practice.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献