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Hot spot detection with satellite images, especially with synthetic aperture radar (SAR) images is still a challenging task. Several researchers have used TM/optical data for identification of hot spot but the use of SAR data is very limited for this type of application. The fusion of SAR data with TM/optical data may add additional information which in turn will lead for enhancement of detection capability of the hot spot. Therefore, this study explores the possibility of fusion of Moderate Resolution Imaging Spectroradiometer (MODIS) and Phased Array L-band Synthetic Aperture Radar (PALSAR) satellite images for the hot spot detection. Image fusion is emerging as a powerful tool where information of various sensors can be used for obtaining better results. For this purpose, vegetation greenness and roughness information which is obtained from MODIS and PALSAR satellite images, respectively, are used for fusion, and then, a contextual-based thresholding algorithm is applied to the fused image for hot spot detection. The proposed approach comprises of two steps: (1) application of genetic algorithm-based scheme for image fusion of MODIS and PALSAR satellite images, and (2) classification of the fused image as either hot spot or non-hot spot pixels by employing a contextual thresholding technique. The algorithm is tested over the Jharia Coal Field region of India, where hot spot is one of the major problems and it is observed that the proposed thresholding technique classifies the each pixel of the fused image into two categories: hot spot and non-hot spot and the proposed approach detects the hot spot with better accuracy and less false alarm. 相似文献
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Soyeun Kim Godwin Uyi Ojo Rukhe Zehra Zaidi Raymond L. Bryant 《Singapore journal of tropical geography》2012,33(1):34-48
For all its vitality political ecology often appears to be a project in which work by Anglo‐Americans in particular, if it is not privileged, certainly predominates. This trend reflects wider language and intellectual tendencies in human geography and the social sciences that distort the development of the field by downplaying or obscuring the contributions of many non‐Anglo‐Americans and by naturalizing Anglo‐American assumptions at the heart of research. The latter in turn determine what constitutes ‘good’ work – even as there is no single definition of political ecology. Arguing against this tendency, this paper draws on postcolonial thinking to emphasize the need to reassess and reorient the field as ‘other’ political ecologies are feasible and desirable. 相似文献
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Rukhe Zehra Zaidi 《Singapore journal of tropical geography》2012,33(1):63-76
The widening empirical and theoretical scope of political ecology has been accompanied by discussions on the coherence and content of the field. While these evaluations necessarily focus on what is included in the conceptual boundaries of political ecology, little is said about what is left out. This paper considers the struggle for land rights by Anjuman Muzareen Punjab, a movement of tenant farmers in Pakistan, to illustrate how changing research priorities, difficulties in crossing theoretical and conceptual boundaries, and geopolitics and research access can hinder the visibility of particular forms of socioenvironmental events in mainstream political ecology scholarship. 相似文献
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Mustafa Erdik Karin Sesetyan Mine Demircioglu Ufuk Hancilar Can Zulfikar Eser Cakti Yaver Kamer Cem Yenidogan Cuneyt Tuzun Zehra Cagnan Ebru Harmandar 《Acta Geophysica》2010,58(5):855-892
The almost-real time estimation of ground shaking and losses after a major earthquake in the Euro-Mediterranean region was performed in the framework of the Joint Research Activity 3 (JRA-3) component of the EU FP6 Project entitled “Network of Research Infra-structures for European Seismology, NERIES”. This project consists of finding the most likely location of the earthquake source by estimating the fault rupture parameters on the basis of rapid inversion of data from on-line regional broadband stations. It also includes an estimation of the spatial distribution of selected site-specific ground motion parameters at engineering bedrock through region-specific ground motion prediction equations (GMPEs) or physical simulation of ground motion. By using the Earthquake Loss Estimation Routine (ELER) software, the multi-level methodology developed for real time estimation of losses is capable of incorporating regional variability and sources of uncertainty stemming from GMPEs, fault finiteness, site modifications, inventory of physical and social elements subjected to earthquake hazard and the associated vulnerability relationships. 相似文献
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Cyanuric acid is a suspected gastrointestinal or liver toxicant in humans. Therefore, determination of trace cyanuric acid is very important, in this work a novel, sensitive, and reliable method was developed using differential pulse polarography. Optimum conditions for analytical determination were found to be at a pH of 9.5, Britton–Robinson at a reduction potential of ?105 mV. Experimental results indicate an excellent linear correlation between the peak current and the concentration in the range of cyanuric acid from 0.5 to 27.0 µM (0.06–3.5 µg mL?1) with a correlation coefficient of 0.997. The limit of detection and limit of quantification were obtained as 0.15 and 0.5 µM (0.02–0.06 µg mL?1), respectively. The proposed method was successfully applied to the determination of cyanuric acid in pool water and in spiked milk. Cyanuric acid level in swimming pool water was found as 2.54 ± 0.47 µg mL?1 (19.7 ± 2.29 µM) in swimming pool water for N = 4 and 95% confidence interval. The recoveries were found to be sufficient. Also, the standard deviation of the data was low which shows high accuracy and precision of proposed differential pulse polarographic method. The influences of some other commonly found inorganic salts on the determination of cyanuric acid were also examined. Some interfering species were eliminated using complexing agents, e.g., EDTA. 相似文献
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Sumaira Khan Tasneem G. Kazi Muhammad B. Arain Nida F. Kolachi Jameel A. Baig Hassan I. Afridi Abdul Q. Shah 《洁净——土壤、空气、水》2013,41(8):808-815
Sequential extraction procedures are widely used to characterize the different operational fractions with different potential toxicity of metals in environmental solid samples. The present work describes the application of different analytical approaches for sequential extraction of aluminum to evaluate its mobility, availability, and persistent chemical forms in sediment samples of different fresh water ecosystems (lake, canal, and river). The conventional BCR three‐stage sequential extraction procedure (C‐BCR) was modified at each stage, by applying ultrasonic device (U‐BCR), in order to shorten the required shaking time of 16 h for each three steps (excluding the hydrogen peroxide digestion in step 3, which was not performed with ultrasonic bath), could be completed in 40, 50, and 45 min, respectively. The aluminum in all extracts were determination by atomic absorption spectrometry using nitrous oxide – acetylene flame. The accuracy of results obtained from C‐BCR and proposed U‐BCR was verified with literature reported values of certified sediment sample (BCR 701). The overall recoveries of aluminum obtained by proposed U‐BCR were found in the range of 96.7–113% of those values obtained with C‐BCR for all fractions. Use of ultrasonic device, provided a large saving in extraction time relative to conventional shaking. It was observed that major part of Al in real sediment samples (80–83% of total Al) were bound to residual fraction. The acid soluble fraction of aluminum extracted by 0.11 mol/L CH3COOH has good correlation with aluminum content in corresponding water samples of each ecosystem. 相似文献
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GeoJournal - Present study examines the current situation of food insecurity in Banda district of Bundelkhand region on the basis of measures of food quality and food quantity. Coping strategy... 相似文献
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A framework for spatio-temporal scales and concepts from different disciplines: the ‘vulnerability cube’ 总被引：1，自引：0，他引：1
The concept of vulnerability is increasingly used in the fields of disaster risk reduction and climate change adaptation, as well as socioeconomic studies. This paper reviews research inputs into the concept of vulnerability and highlights the challenges of resolving its spatial and temporal variability with building resilience and adaptation. We hypothesise that a clear understanding of scale is key to integrating these related issues, by differentiating three dimensions of scale when analysing relationships between the observed and the intrinsic scale of a given phenomenon, namely space, time and dimensional level. The paper analyses 20 vulnerability assessment approaches, ranging from the global down to the local scale, and positions them with regard to their integration of the spatial component. We then develop a vulnerability cube as a framework to position existing approaches and to map them in a three-dimensional space. The three axes represent space, time and dimension and provide a structure for the different notions of scales and ultimately for a spatial analysis workflow. The vulnerability cube framework helps us to position different vulnerability assessments and to identify overlaps, differences and specific characteristics. Additionally, this three-dimensional conceptualisation allows the identification and discussion of appropriate scaling issues. 相似文献