Geomatics Natural Hazards & Risk最新文献_第3页

Stability analysis of a deep and large open pit based on fine geological modeling and large-scale parallel computing: a case study of Fushun West Open-pit Mine 基于精细地质建模和大规模并行计算的深大型露天矿稳定性分析——以抚顺西露天矿为例

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-10-09 DOI: 10.1080/19475705.2023.2266663

Yuan Gao, Jinduo Li, Tianhong Yang, Wenxue Deng, Dongming Wang, Hao Cheng, Kai Ma

{"title":"Stability analysis of a deep and large open pit based on fine geological modeling and large-scale parallel computing: a case study of Fushun West Open-pit Mine","authors":"Yuan Gao, Jinduo Li, Tianhong Yang, Wenxue Deng, Dongming Wang, Hao Cheng, Kai Ma","doi":"10.1080/19475705.2023.2266663","DOIUrl":"https://doi.org/10.1080/19475705.2023.2266663","url":null,"abstract":"Accurate input of geological elements is essential for evaluating or predicting natural hazards such as subsidence, landslides, and earthquakes. This paper proposes an approach to carry out an open pit’s overall and whole-process mechanical analysis with complex geological conditions, using precise modeling and large-scale parallel calculation techniques. Taking the Fushun West Open-pit Mine (the largest open-pit coal mine in Asia) as an example, through the elaborate multi-method geological investigation, the interfaces of interbedded shales and mudstones, the unloading zones, and the small structures were identified, a detailed 3D geological model was built and finely meshed in full-size with 100 million degrees of freedom, large-scale parallel numerical simulation was then performed, the results agree well with the InSAR monitoring data and in situ observations. Besides, the simulation can replicate the landslides in recent years. Through the simulation, it is possible to locate the potential landslide area, and targeted backfilling schemes for stability treatment were put forward and further simulated. The results indicate that the proposed approach can more effectively and reliably evaluate the Fushun West Open-pit Mine’s overall slope stability and closure plan.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135095833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hazard assessment of a pair of glacial lakes in Nepal Himalaya: unfolding combined outbursts of Upper and Lower Barun 尼泊尔喜马拉雅一对冰川湖的危害评估:展开上巴伦和下巴伦的联合爆发

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-10-09 DOI: 10.1080/19475705.2023.2266219

Manish Raj Gouli, Kaiheng Hu, Nitesh Khadka, Rocky Talchabhadel

{"title":"Hazard assessment of a pair of glacial lakes in Nepal Himalaya: unfolding combined outbursts of Upper and Lower Barun","authors":"Manish Raj Gouli, Kaiheng Hu, Nitesh Khadka, Rocky Talchabhadel","doi":"10.1080/19475705.2023.2266219","DOIUrl":"https://doi.org/10.1080/19475705.2023.2266219","url":null,"abstract":"Due to climate change, the future Glacial Lake Outburst Flood (GLOF) risk is more likely in the Himalayas. Despite several GLOF studies, little attention has been given to the combined surge that can result from a pair of upstream-downstream glacial lakes. We chose Upper and Lower Barun glacial lakes as a pilot study due to the region’s increasing population and hydropower investments and the possible outbursts of upper-lower glacial lakes. This study mainly considered four scenarios (100 and 50% breach combination of upper-lower lakes), using a two-dimensional dam break model and inundation propagation. Based on our observations, the glaciers in the study area shrank by 33 km2, and the two glacial lakes expanded by 2.06 km2 between 1976 and 2020. The modeling result suggests that the single flood triggered by Upper Barun cannot travel beyond 50 km; however, the combined flow from the lakes could reach over 85 km. Our results illustrate that at least 60 buildings, motorable bridges, and infrastructures of Arun hydropower along the river course have high damage potential. The study insights can be helpful for effectively planning and formulating various disaster risk reduction initiatives to mitigate the likely effects of glacial lake(s) outbursts.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135095249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stability analysis and support requirements for haulage drift in the vicinity of mined stopes 稳定性分析和支持要求运输平巷附近的开采采场

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-10-08 DOI: 10.1080/19475705.2023.2265146

Huaibin Li, Changxiang Wang, Xinzhu Hua, Xingdong Zhao, Bibo Dai, Zujun Huang

{"title":"Stability analysis and support requirements for haulage drift in the vicinity of mined stopes","authors":"Huaibin Li, Changxiang Wang, Xinzhu Hua, Xingdong Zhao, Bibo Dai, Zujun Huang","doi":"10.1080/19475705.2023.2265146","DOIUrl":"https://doi.org/10.1080/19475705.2023.2265146","url":null,"abstract":"In this study, combined empirical, numerical, and in-situ monitoring methods were combined to carry out stability analyses and support design for a haulage drift subjected to mining activity. The rock mass quality of the haulage drift was characterized by the RMR, Q, and GSI, and the rock mass properties were calculated. The support requirements for haulage drift during mining were determined by rock mass classification systems. RS2 was used to analyze the plastic zone and displacement of the haulage drift during mining. After the stope was mined, the surrounding rock exhibited a butterfly plastic zone with an asymmetric distribution, and the roof damage was most severe near the stope side. Overall, the haulage drift tended to move in the stope direction, which is consistent with engineering expectations. The support systems determined using the empirical method were analyzed using RS2 and UNWEDGE software. The maximum plastic zone depth of the roof decreased from 4.2 to 2.01 m, and the safety factor of the unstable wedge block increased from 0 to 10.2 after support. In-situ drilling detection shows that the failure depth of the haulage drift roof is 2.37 m. Therefore, a combination of empirical, numerical, and in-situ monitoring methods can be effective for quantitative stability assessments and support design optimization of haulage drifts in the vicinity of mined stopes.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135250849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Site response measurements and implications to soil liquefaction potential using microtremor H/V in Greater Metro Manila, Philippines 利用微震H/V测量菲律宾大马尼拉地区的现场反应及其对土壤液化潜力的影响

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-10-05 DOI: 10.1080/19475705.2023.2256936

A. Daag, L. E. Aque, O. Locaba, R. Grutas, R. Solidum

{"title":"Site response measurements and implications to soil liquefaction potential using microtremor H/V in Greater Metro Manila, Philippines","authors":"A. Daag, L. E. Aque, O. Locaba, R. Grutas, R. Solidum","doi":"10.1080/19475705.2023.2256936","DOIUrl":"https://doi.org/10.1080/19475705.2023.2256936","url":null,"abstract":"This research explores the use of microtremor horizontal-to-vertical spectral ratio (H/V) in obtaining site response characteristics and investigating its relationship with soil liquefaction potential in Greater Metro Manila. We performed single station microtremor measurements in 61 sites along with in situ geotechnical techniques to verify liquefaction potential. The resulting 238 spectral curves were classified according to dominant features and subsequently grouped with the calculated liquefaction potential index (LPI) of the soil. Based on a robust comparison of obtained primary parameters, it is revealed that the shape of the H/V curve, its predominant period and relative amplitude are fundamentally linked to the spatial variability and the shear strength of soils. Therefore, areas of high seismic demand can also have high liquefaction potential, and vice versa. We then correlated the predominant period with the LPI of the soil and extracted a boundary using simple statistical techniques to classify high and low potential for liquefaction subsequently validating its use as a complementary tool for rapid site-specific liquefaction assessment. Such findings are a novel contribution to liquefaction studies employing rapid techniques since the application of microtremors to liquefaction in the Philippines has not been practiced extensively.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"440 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135483567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Causes and effects of Shisper glacial lake outburst flood event in Karakoram in 2022 2022年喀喇昆仑地区Shisper冰湖溃决洪水事件成因及影响

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-10-03 DOI: 10.1080/19475705.2023.2264460

Sandeep Kumar Mondal, Vatsal D. Patel, Rishikesh Bharti, Ramesh P. Singh

{"title":"Causes and effects of Shisper glacial lake outburst flood event in Karakoram in 2022","authors":"Sandeep Kumar Mondal, Vatsal D. Patel, Rishikesh Bharti, Ramesh P. Singh","doi":"10.1080/19475705.2023.2264460","DOIUrl":"https://doi.org/10.1080/19475705.2023.2264460","url":null,"abstract":"Karakoram Himalayas are vulnerable to glacial lake outburst floods (GLOFs), which cause catastrophic floods in the surrounding areas. The increasing natural and anthropogenic activities, especially in the Indo-Gangetic Plains at the southern flank of the towering Himalayas, could be the cause of climate change affecting the frequency of the natural hazards in the Himalayas. In the present study, a detailed analysis of the Shisper Lake breach of 7 May 2022 is carried out using satellite remote sensing. A decreasing trend in the glacial mass balance is observed between 2017 and 2021; in this period, frequent GLOF episodes occurred. A pronounced decline in the snow cover and glacial debris (before the cascade) and an abnormal increase in land surface temperature (LST) retrieved from satellite data could be responsible for the enhanced snow/glacial melting prior to the breach. Alteration in glacial mobility (cm/12 days) is observed at the locations where the glacier melts due to an increase in LST with increased debris cover. In the paper, we have studied changes in water quality and land cover along the stream after the GLOF. An increment in normalized difference turbidity index (NDTI) is observed before the flood showing turbulence and sediment load. Increased glacial melt contribution into the stream results in increased flow rate and decreased water quality as observed through normalized difference water index (NDWI) and normalized difference chlorophyll index (NDCI), near the Karakoram Highway Bridge. Sentinel-1 backscatter coefficient indicates increased discharge from the melting of glaciers. A significant reduction in co-flood coherence is observed, attributed to the bridge collapse and severe bank erosion.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135740399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Creeping slopes in NW Himalaya and Joshimath slide: constraints from GPS measurements 喜马拉雅西北部的爬坡和Joshimath滑坡:来自GPS测量的约束

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-09-28 DOI: 10.1080/19475705.2023.2263622

V. K. Gahalaut, Niraj Gurjar, Avanish Kumar, Shubham Rajewar, Aditya Mohanty, Amit Kumar, Rajeev Kumar Yadav, S. P. Sati, Saroj Mondal

{"title":"Creeping slopes in NW Himalaya and Joshimath slide: constraints from GPS measurements","authors":"V. K. Gahalaut, Niraj Gurjar, Avanish Kumar, Shubham Rajewar, Aditya Mohanty, Amit Kumar, Rajeev Kumar Yadav, S. P. Sati, Saroj Mondal","doi":"10.1080/19475705.2023.2263622","DOIUrl":"https://doi.org/10.1080/19475705.2023.2263622","url":null,"abstract":"Slow slope movement is very common in the Himalayan region. In most cases, the topsoil, weathered rock mass, debris of paleo-landslide or of glacial origin, etc. slowly slides until it stabilizes or fails. In some cases, even the bedrock may be involved in sliding. Here we report four such sliding slopes on which GPS were actually installed for tectonic deformation monitoring in the Himalayan region after a careful investigation but they recorded slow slope sliding. The slow sliding motion on these slopes varied from 10-15 mm/year to 5-6 m/year. The slow slides did not show any anomalous seasonal variation due to hydrological loading. Amongst the four, the Joshimath slide exhibited a large variation in sliding motion which varied from less than a mm/day to 15 mm/day during 2022-2023, causing cracks on the ground and buildings and panic amongst the residents. Even the highly non-linear motion with a sudden change in sliding motion at Joshimath appears to be of viscous creep type. The exact time of initiation of this episode of slide is not known but the available InSAR analyses imply that it is moving at least since 2018. Its motion does not seem to be affected by the February 7, 2021 floods, however, whether the anthropogenic activities around the sliding zone influenced its motion and initiation, remains to be debated.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135344919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Flood modelling and its impacts on groundwater vulnerability in sub-Himalayan region of Pakistan: integration between HEC-RAS and geophysical techniques 巴基斯坦亚喜马拉雅地区洪水模拟及其对地下水脆弱性的影响:HEC-RAS与地球物理技术的整合

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-09-25 DOI: 10.1080/19475705.2023.2257360

Abrar Niaz, Umair Bin Nisar, Sarfraz Khan, Rashida Faiz, Asim Javed, Jawad Niaz, Muhammad Aaqib, Mohsin Raza, Bikram Bhusal

{"title":"Flood modelling and its impacts on groundwater vulnerability in sub-Himalayan region of Pakistan: integration between HEC-RAS and geophysical techniques","authors":"Abrar Niaz, Umair Bin Nisar, Sarfraz Khan, Rashida Faiz, Asim Javed, Jawad Niaz, Muhammad Aaqib, Mohsin Raza, Bikram Bhusal","doi":"10.1080/19475705.2023.2257360","DOIUrl":"https://doi.org/10.1080/19475705.2023.2257360","url":null,"abstract":"Hydropower projects play a pivot role in the development of a country. Constructions of reservoirs create job opportunities and provide cheap energy but at the same time cause several environmental issues. The current study utilizes geoelectric and flood modelling data to develop a relationship between flood scenarios and their effect on river flows in association with the vulnerability of groundwater due to hydroelectric projects on Neelum River, Pakistan. The resistivity data delineated local aquifer systems that comprised both confined and unconfined aquifers ranging from 05 to 48 m depth, having poor to weak protective capacity with good groundwater development potential. The flood zonation models indicate a decline in the flow rate of the Neelum River from 317 to 39 m3/s with a drop in stage and flow velocity that contributes to a high risk of leachate penetration in the poorly protected shallow aquifer. The aquifer systems that mostly lie near the banks of the river face a serious threat of contamination due to low river flow. The flood modelling revealed that in case of dam burst, maximum probable flood will affect the land cover of 30,43,250 m2 and 33,64,433 m2 in Muzaffarabad and Patikka areas, respectively, affecting major population.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135817388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimizing soil erosion estimates of RUSLE model by analyzing land use/cover dynamics in upper Awash River Basin, Central Ethiopia 埃塞俄比亚中部阿瓦什河上游土地利用/覆被动态优化RUSLE模型土壤侵蚀估算

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-09-15 DOI: 10.1080/19475705.2023.2257363

Eyasu Mekonnen, Asfaw Kebede, Solomon Asfaw, Samuel Feyissa

{"title":"Optimizing soil erosion estimates of RUSLE model by analyzing land use/cover dynamics in upper Awash River Basin, Central Ethiopia","authors":"Eyasu Mekonnen, Asfaw Kebede, Solomon Asfaw, Samuel Feyissa","doi":"10.1080/19475705.2023.2257363","DOIUrl":"https://doi.org/10.1080/19475705.2023.2257363","url":null,"abstract":"The Revised Universal Soil Loss Equation (RUSLE) is the most widely used erosion model for decision making on conservation priority. However, interpreting estimates of the mean annual soil loss alone could not accurately depict the spatial variation of soil erosion severity due to its inherent mathematical errors. This study aims to optimize the model’s outputs through detailed analysis of land use/cover dynamics in Upper Awash River Basin, central Ethiopia (7815.1 km2). The analysis include annual rate of change, net gain or loss, and conversion pathways. Results of the estimated mean annual soil loss in the basin varies between 4.1 t/ha/y and 5.1 t/ha/y during three consecutive decades (1990-2000, 2000-2010, and 2010-2020). The cultivated land cover exhibits slight erosion severity (< 5 t/ha/y), while contributing up to 59% the total annual soil loss (3198.8 Mt/ha). Although the net loss of cultivated land cover outweighing the gain during these decades, it progressively encroaches forests (142.2 km2), shrubs (780.8 km2), and grasslands (274.5 km2). Such net loss of protective land covers will inevitably increase the soil erosion risk. Findings from the study would be useful, enabling conservation practitioners to understand the overall severity of soil erosion and make informed decisions.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135436323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The influence of saturation and loading angle on sandstone damage characteristics after freeze-thaw cycle 饱和度和加载角度对冻融循环后砂岩损伤特性的影响

3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-09-14 DOI: 10.1080/19475705.2023.2250526

Shihao Yuan, Jiaxu Jin, Xiaoli Liu, Shaohua Li, Bing Liang

{"title":"The influence of saturation and loading angle on sandstone damage characteristics after freeze-thaw cycle","authors":"Shihao Yuan, Jiaxu Jin, Xiaoli Liu, Shaohua Li, Bing Liang","doi":"10.1080/19475705.2023.2250526","DOIUrl":"https://doi.org/10.1080/19475705.2023.2250526","url":null,"abstract":"The strength deterioration and fracture tendency of freeze-thaw rock determine the construction and operation safety of rock engineering. This article conducted compression-shear composite load tests on sandstones with various saturations to examine the failure law of rocks in cold climates and the contributing elements of strength degradation. It was found that with an increase in saturation and loading angle, the compressive strength and elastic modulus dropped. The concept of freeze crack threshold and saturation threshold was proposed. The peak shear stress was negatively correlated with saturation and positively correlated with loading angle. The σCI (crack initiation stress) and σCD (crack damage stress) in the saturated state were only 39.91% and 45.18% of those in the dry state. Serious damage occurred at high saturations, which is consistent with the scanning electron microscopy results. The σCI and σCD under 30°loading angle are 49.72% and 42.91% of those under uniaxial, respectively. This is mainly due to the change of the failure mode from tensile-shear failure to combined tension-shear failure, and finally to single-shear failure. A strength prediction model was established based on sandstone damage characteristics. The research results have important reference value for rock engineering design in frigid climates and complex load environments.","PeriodicalId":51283,"journal":{"name":"Geomatics Natural Hazards & Risk","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134912352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multi-temporal InSAR and Sentinel-1 for assessing land surface movement of Joshimath town, India 印度Joshimath镇地表运动的多时相InSAR和Sentinel-1评估

IF 4.2 3区地球科学

Geomatics Natural Hazards & Risk Pub Date : 2023-09-05 DOI: 10.1080/19475705.2023.2253972

Hari Shankar, Prakash Chauhan, D. Singh, Ravi Bhandari, C. M. Bhatt, Arijit Roy, Suresh Kannaujiya, Raghavendra Pratap Singh

引用次数: 1