排序方式： 共有97条查询结果，搜索用时 527 毫秒
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Haoyuan Hong Biswajeet Pradhan Maher Ibrahim Sameen Bahareh Kalantar Axing Zhu Wei Chen 《Landslides》2018,15(4):753-772
Landslide is a natural disaster that threatens human lives and properties worldwide. Numerous have been conducted on landslide susceptibility mapping (LSM), in which each has attempted to improve the accuracy of final outputs. This study presents a novel region-partitioning approach for LSM to understand the effects of partitioning a focused region into smaller areas on the prediction accuracy of common regression models. Results showed that the partitioning of the study area into two regions using the proposed method improved the prediction rate from 0.77 to 0.85 when support vector machine was used, and from 0.87 to 0.88 when logistic regression model was utilized. The spatial agreements of the models were also improved after partitioning the area into two regions based on Shannon entropy equations. Our comparative study indicated that the proposed method outperformed the geographically weighted regression model that considered the spatial variations in landslide samples. Overall, the main advantages of the proposed method are improved accuracy and the reduction of the effects of spatial variations exhibited in landslide-conditioning factors. 相似文献
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Basal stem rot (BSR) is a type of disease that induces oil palm death within a short span of the appearance of symptoms. BSR early detection would facilitate to curb this by adopting appropriate strategies. In this paper, a systematic review was undertaken to demonstrate the need for authentic health condition monitoring of oil palm plantations. The currently used remotely sensed (RS) techniques for BSR detection and classification were reviewed. Several kinds of RS techniques were exerted for BSR detection and its severity classification up to four levels. It was identified that applied geospatial technologies, including multispectral and hyperspectral remote sensing, terrestrial laser scanning, spatial maps, tomography images, intelligent e-nose and Microfocus X-ray fluorescence, were capable of distinguishing infected oil palms from the non-infected ones. Furthermore, some of them are able to categorize BSR severity level up to four levels as well as of its early detection. 相似文献
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Biswajeet Pradhan 《地学前缘(英文版)》2021,12(6):354-355
Energy is a vital commodity that sustains human lives,as well as eco-nomic processes.The challenges towards energy generation,demand and supply are plenty owing to the use of fossil fuels leading to climate change and environmental problems like water and air pollution.With the increasing awareness over climate change,post Paris Agreement,the role of energy plays a key role towards achieving the proposed tar-get.The contributions in this Special Issue of Geoscience Frontiers on En-ergy includes 8 papers from esteemed research groups worldwide which explores,highlights and provide new insights towards the vari-ous aspects of energy. 相似文献
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Groundwater potential zonation for basaltic watersheds using satellite remote sensing data and GIS techniques 总被引：5，自引：0，他引：5
Biswajeet Pradhan 《Central European Journal of Geosciences》2009,1(1):120-129
This paper summarizes the findings of groundwater potential zonation mapping at the Bharangi River basin, Thane district, Maharastra, India, using Satty’s Analytical Hierarchal Process model with the aid of GIS tools and remote sensing data. To meet the objectives, remotely sensed data were used in extracting lineaments, faults and drainage pattern which influence the groundwater sources to the aquifer. The digitally processed satellite images were subsequently combined in a GIS with ancillary data such as topographical (slope, drainage), geological (litho types and lineaments), hydrogeomorphology and constructed into a spatial database using GIS and image processing tools. In this study, six thematic layers were used for groundwater potential analysis. Each thematic layer’s weight was determined, and groundwater potential indices were calculated using groundwater conditions. The present study has demonstrated the capabilities of remote sensing and GIS techniques in the demarcation of different groundwater potential zones for hard rock basaltic basin. 相似文献
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Landslide Susceptibility Mapping along Bhalubang–Shiwapur Area of Mid-Western Nepal Using Frequency Ratio and Conditional Probability Models 总被引：3，自引：3，他引：0
Amar Deep Regmi Kohki Yoshida Hamid Reza Pourghasemi Megh Raj DhitaL Biswajeet Pradhan 《山地科学学报》2014,11(5):1266-1285
Roads constructed in fragile Siwaliks are prone to large number of instabilities. Bhalubang–Shiwapur section of Mahendra Highway lying in Western Nepal is one of them. To understand the landslide causative factor and to predict future occurrence of the landslides, landslide susceptibility mapping(LSM) of this region was carried out using frequency ratio(FR) and weights-of-evidence(W of E) models. These models are easy to apply and give good results. For this, landslide inventory map of the area was prepared based on the aerial photo interpretation, from previously published/unpublished reposts, and detailed field survey using GPS. About 332 landslides were identified and mapped, among which 226(70%) were randomly selected for model training and the remaining 106(30%) were used for validation purpose. A spatial database was constructed from topographic, geological, and land cover maps. The reclassified maps based on the weight values of frequency ratio and weights-of-evidence were applied to get final susceptibility maps. The resultant landslide susceptibility maps were verified andcompared with the training data, as well as with the validation data. From the analysis, it is seen that both the models were equally capable of predicting landslide susceptibility of the region(W of E model(success rate = 83.39%, prediction rate = 79.59%); FR model(success rate = 83.31%, prediction rate = 78.58%)). In addition, it was observed that the distance from highway and lithology, followed by distance from drainage, slope curvature, and slope gradient played major role in the formation of landsides. The landslide susceptibility maps thus produced can serve as basic tools for planners and engineers to carry out further development works in this landslide prone area. 相似文献
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Urban Sprawl Analysis of Tripoli Metropolitan City (Libya) Using Remote Sensing Data and Multivariate Logistic Regression Model 总被引：1，自引：0，他引：1
Abubakr A. A. Alsharif Biswajeet Pradhan 《Journal of the Indian Society of Remote Sensing》2014,42(1):149-163
The main objective of this paper is to analyze urban sprawl in the metropolitan city of Tripoli, Libya. Logistic regression model is used in modeling urban expansion patterns, and in investigating the relationship between urban sprawl and various driving forces. The 11 factors that influence urban sprawl occurrence used in this research are the distances to main active economic centers, to a central business district, to the nearest urbanized area, to educational area, to roads, and to urbanized areas; easting and northing coordinates; slope; restricted area; and population density. These factors were extracted from various existing maps and remotely sensed data. Subsequently, logistic regression coefficient of each factor is computed in the calibration phase using data from 1984 to 2002. Additionally, data from 2002 to 2010 were used in the validation. The validation of the logistic regression model was conducted using the relative operating characteristic (ROC) method. The validation result indicated 0.86 accuracy rate. Finally, the urban sprawl probability map was generated to estimate six scenarios of urban patterns for 2020 and 2025. The results indicated that the logistic regression model is effective in explaining urban expansion driving factors, their behaviors, and urban pattern formation. The logistic regression model has limitations in temporal dynamic analysis used in urban analysis studies. Thus, an integration of the logistic regression model with estimation and allocation techniques can be used to estimate and to locate urban land demands for a deeper understanding of future urban patterns. 相似文献
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Yusuf Ahmed Yusuf Biswajeet Pradhan Mohammed O. Idrees 《Journal of the Indian Society of Remote Sensing》2014,42(4):829-837
Alteration in climatic pattern has resulted to a steady decline in quality of life and the environment, especially in and around urbanized areas. These areas are faced with increasing surface temperature arising mostly from human activities and other natural sources; hence land surface temperature has become an important variable in global climate change studies. In this paper, Landsat TM/ETM imagery acquired between 1997 and 2013 were used to extract ground brightness temperature and land use/land cover change in Kuala Lumpur metropolis. The main objective of this paper is to examine the effectiveness of quantifying UHI effects, in space and time, using remote sensing data and, also, to find the relationship between UHI and land use change. Four land use types (forest, farmland, built-up area and water) were classified from the Landsat images using maximum likelihood classification technique. The result reveals that Greater KL experienced an increase in average temperature from 312.641°K to 321.112°K which was quite eminent with an average gain in surface temperature of 8.4717°K. During the period of investigation (1997–2013), generally high temperature is been experienced mostly in concentrated built-up areas, the less concentrated have a moderate to intermediate temperature. Again, the study also shows that low and intermediate temperature classes loss more spatial extent from 2,246.89 Km2 to 1,164.53 Km2 and 6,102.42 Km2 to 3,013.63 Km2 and a gain of 4,165.963 Km2 and 307.098 Km2 in moderate and high temperature respectively from 1997 to 2013. The results of this study may assist planners, scientists, engineers, demographers and other social scientists concerned about urban heat island to make decisions that will enhance sustainable environmental practices. 相似文献
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Amar Deep Regmi Kohki Yoshida Megh Raj Dhital Biswajeet Pradhan 《Environmental Earth Sciences》2014,71(6):2711-2727
Sangrumba landslide is one of the largest and the most active landslides in Nepal Himalaya. Geologically the landslide belongs to the Higher Himalaya and consists of Pre-Cambrian biotite–garnet and sillimanite gneiss with some quartzite. The present paper aims at describing various degrees of rock weathering and their effect in Sangrumba landslide. Field study followed by mineralogical, geochemical and geotechnical analyses of the collected rock and soil samples from the landslide zone were used in characterizing weathering degree. The gneisses are intensely weathered while quartzite is unweathered. Petrographical and X-ray diffraction analyses showed that the rocks in the landslide zone had undergone weathering process with the formation of different types of clay minerals as kaolinite, vermiculite, smectite and chlorite. This was further confirmed by the Scan Electron Microscope and Energy Dispersive X-ray analyses. These clay minerals drastically reduced the rock strength facilitating the extensive failure of the Sangrumba landslide. The major and trace element composition of the rock and soil samples was calculated from the XRF analyses. The geochemical analyses and weathering indexes of rocks showed that they are significantly weathered and had a major influence in the formation of the Sangrumba landslide. In addition, mechanical strength measurement of rock/soil showed that the strength drastically decreases as the weathering intensity increases. Rainfall followed by the rock type are the most dominant parameters influencing the weathering process which leads to the formation of large landslide as the present one. These findings can be used in other areas with similar geological and topographical conditions. 相似文献