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Investigating the tourism image of mountain scenic spots in China through the lens of tourist perception 被引量:2
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作者 LI Feng-jiao LIAO Xia +3 位作者 LIU Jia-ming JIANG Li-li WANG Meng-di LIU Jin-feng 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2298-2314,共17页
A favorable tourism image of high-quality mountain scenic spots(HQMSS)is crucial for tourism prosperity and sustainability.This paper establishes a framework for investigating the tourism image based on cognitive-emot... A favorable tourism image of high-quality mountain scenic spots(HQMSS)is crucial for tourism prosperity and sustainability.This paper establishes a framework for investigating the tourism image based on cognitive-emotion theory and uses natural language processing(NLP)tools to clarify the cognition,emotion,and overall tourist image of the HQMSS in China from the perspective of tourist perception.This paper examines the multi-dimensional spatial differentiation of China's overall image,including province,scenic spot scales,as well as the spatial pattern of the overall comprehensive tourism image.Strategies for comprehensively improving HQMSS's tourism image are also formulated.The results show that:(1)The cognitive image of Chinese HQMSS is categorized into core and marginal images,and the core images such as scenery and cable car are the expression of the uniqueness of mountainous scenic spots.Additionally,the cognitive image is classified into six dimensions:tourism environment,tourism supporting facilities,tourism experience,tourism price,tourism service,and tourism safety.(2)Positive emotions are the dominant mood type of HQMSS in China,followed by neutral emotions,with negative emotions being the least frequent.Emotional images vary across dimensions,with tourism environment and tourism experience evoking relatively higher emotion.(3)The spatial pattern of HQMSS for each dimension at the national,provincial,and scenic scales is diversifying.This article provides a multidimensional perspective for investigating the tourism image of mountainous scenic spots,proposes targeted recommendations to improve the overall image of HQMSS in China,and can greatly contribute to the sustainable development of mountain tourism. 展开更多
关键词 Mountain scenic spot Tourism image Spatial differentiation Natural language processing Cognitive-emotion theory Tourist perception
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Development and Quality Improvement of Lianqingshan Scenic Spot in Tengzhou City
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作者 ZHANG Dongmei WANG Yifan 《Journal of Landscape Research》 2024年第1期91-95,共5页
Since the 21st century,China’s overall national strength has increased continuously.With the rapid development of the tourism industry,people have an increasingly strong demand for travel.Firstly,tourists’satisfacti... Since the 21st century,China’s overall national strength has increased continuously.With the rapid development of the tourism industry,people have an increasingly strong demand for travel.Firstly,tourists’satisfaction to Lianqingshan Scenic Spot was surveyed,and then the types of tourism resources,current development situation and problems in the scenic spot were analyzed.Finally,some countermeasures and suggestions for its development and quality improvement were put forward.It is found that based on the environmental quality,safety and service quality of Lianqingshan Scenic Spot,the basic situation of the development of the scenic spot was investigated,and the comprehensive satisfaction of each item is 3.30,3.24 and 3.32.The tourists of the scenic spot is mainly from Tengzhou City and its surrounding cities,and the popularity of the scenic spot is relatively low.The management personnel of the scenic spot needs to increase the tourist flow by improving its exposure.The problems of the scenic spot include low popularity,poor environmental quality,low safety of tourists,poor operating condition of catering industry and service quality of service personnel. 展开更多
关键词 Lianqingshan scenic spot PROBLEMS COUNTERMEASURES
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 FRACTURES Development characteristics Controlling factors Shale oil Sweet spot
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Key geological factors governing sweet spots in the Wufeng-Longmaxi shales of the Sichuan Basin,China
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作者 Zongquan Hu Zengqin Liu +4 位作者 Wei Du Zhenrui Bai Ruyue Wang Chuanxiang Sun Dongjun Feng 《Energy Geoscience》 EI 2024年第3期163-174,共12页
Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characterist... Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characteristics are investigated to identify key factors governing sweet spots.Siliceous shales with good preservation conditions in the Fuling Field exhibit large thickness,high TOC content and thin-section porosity(TSP),and well-developed OM macropores,thus high initial production and estimated ultimate recovery(EUR).Thin carbonate-containing siliceous shales with good preservation conditions in the Weirong Field feature medium-to-high TOC and well-developed OM macropores but low TSP,leading to high initial production but low EUR.Siliceous shales with poor preservation conditions in the Wulong Field are characterized by large thickness,high TOC,low TSP and poorly-developed OM macropores,causing low initial production and EUR.Both sedimentary and preservation conditions are intrinsic decisive factors of sweet spots,as they control the mineral composition,TOC,and OM macropore development.Deep-water shales in transgressive systems tracts(TSTs)exhibit better-developed OM macropores and greater TOC compared to highstand systems tracts(HSTs).OM macropores are most prevalent in siliceous shales,followed by carbonate-containing siliceous shales and then argillaceous shales.Furthermore,good preservation conditions are conducive to retain OM macropores with low pore aspect ratio(PAR).Comparison among the three fields shows that high-TOC silicious shales with good preservation conditions are the highest in TSP and EUR.Therefore,organic richness,lithofacies,and preservation conditions are the major factors which determine OM pore development,governing the sweet spots of the Wufeng-Longmaxi shales. 展开更多
关键词 Shale gas Organic matter pores Sweet spot Wufeng-Longmaxi shales Sichuan basin
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Research status and hotspots of tight junctions and colorectal cancer:A bibliometric and visualization analysis
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作者 Hui-Min Li Yin Liu +5 位作者 Meng-Di Hao Xiao-Qing Liang Da-Jin Yuan Wen-Bin Huang Wen-Jie Li Lei Ding 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3705-3715,共11页
BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding... BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding the role of tight junction(TJ)proteins in the occurrence and progression of CRC.The causal relationship between the presence of specific TJ proteins and the development of CRC has also been confirmed.Despite the large number of publications in this field,a bibliometric study to review the current state of research and highlight the research trends and hotspots in this field has not yet been performed.AIM To analyze research on TJs and CRC,summarize the field’s history and current status,and predict future research directions.METHODS We searched the Science Citation Index Expanded database for all literature on CRC and TJs from 2001-2023.We used bibliometrics to analyze the data of these papers,such as the authors,countries,institutions,and references.Co-authorship,co-citation,and co-occurrence analyses were the main methods of analysis.CiteSpace and VOSviewer were used to visualize the results.RESULTS A total of 205 studies were ultimately identified.The number of publications on this topic has steadily increased since 2007.China and the United States have made the largest contributions to this field.Anticancer Research was the most prolific journal,publishing 8 articles,while the journal Oncogene had the highest average citation rate(68.33).Professor Dhawan P was the most prolific and cited author in this field.Co-occurrence analysis of keywords revealed that“tight junction protein expression”,“colorectal cancer”,“intestinal microbiota”,and“inflammatory bowel disease”had the highest frequency of occurrence,revealing the research hotspots and trends in this field.CONCLUSION This bibliometric analysis evaluated the scope and trends of TJ proteins in CRC,providing valuable research perspectives and future directions for studying the connection between the two.It is recommended to focus on emerging research hotspots,such as the correlations among intestinal microbiota,inflammatory bowel disease,TJ protein expression,and CRC. 展开更多
关键词 Colorectal cancer Tight junctions Bibliometric analysis Research trends Hot spots
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Research Progress and Prospect of Tourism Carbon Emissions and Its Uncertainty Analysis Under the Goal of Low-Carbon Scenic Spots
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作者 Aihong Wang Qiguang Lyu 《Proceedings of Business and Economic Studies》 2023年第2期25-32,共8页
Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of ... Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of China’s national economy,and scenic spots are the main sites of tourism activities.Research on carbon emissions in scenic spots is of great significance for the construction of low-carbon scenic spots and the realization of the dual carbon goal.In this paper,the research on carbon emissions in tourism is reviewed,the current research progress is discussed,and further prospects are made.The research on tourism carbon emissions in China has a good foundation and achieved certain results.However,there are few studies on micro-scales such as scenic spots.The statistical data caliber and measurement methods of carbon emissions are not uniform,and there is a general lack of uncertainty analysis.Future research should focus on building a multi-spatial dimension research system,unifying the statistical caliber and measurement methods of carbon emission data,increasing uncertainty analysis,and ensuring the robustness of research results. 展开更多
关键词 Low-carbon scenic spot Carbon emissions Uncertainty analysis
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Cultivation and Management of Low-carbon Scenic Spots——A case study of Yuntai Mountain Scenic Area in Henan Provicne of China 被引量:1
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作者 史云 田甜 许晓明 《Journal of Landscape Research》 2011年第4期57-60,64,共5页
After analysis of connotation of low-carbon scenic spots,the paper considered that a perfect low-carbon scenic spot is a comprehensive integrity with satisfying tourists' lowest tourist experience effect as the pr... After analysis of connotation of low-carbon scenic spots,the paper considered that a perfect low-carbon scenic spot is a comprehensive integrity with satisfying tourists' lowest tourist experience effect as the premise and with low energy consumption,low pollution and low emission as the foundation.Low-carbon tourist scenic spots had been classified into three types which are ecological type,cultural type and coupling type of ecology and culture.Representatives of each type of tourist scenic spot were illustrated.It proposed that government should play the leading role in cultivation of low-carbon scenic spot;tourism industry should enhance self supervision;tourism development mode should be transformed and upgrading of tourist products should be realized.By taking Yuntai Mountain Scenic Area of Henan Province for example,based on low-carbon tourist resources,low-carbon development of management,following measures realizing low-carbon economy were put forward:① purifying air quality and beautifying environment of scenic area;② sifting laggard productivity and protecting ecological resources in the scenic area by many means;③ sticking to low-carbon environmental protection concept and completing infrastructure service;④ developing tourist native products and souvenirs based on local resources;⑤ applying electronic access control ticket system,intelligent monitor system and LED information and communication platform,so as to achieve low-carbon management. 展开更多
关键词 Low-carbon scenic spot CULTIVATION and development Yuntai MOUNTAIN scenic Area Management
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Research on the Value of Chinese Famous Mountainous Scenic Spots in the Perspective of Cultural Landscape 被引量:1
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作者 刘强 《Journal of Landscape Research》 2012年第6期30-32,共3页
After summarizing relevant researches on famous mountainous scenic spots and the development of cultural landscapes in world cultural heritages, the paper has analyzed the value of famous mountainous scenic spots in C... After summarizing relevant researches on famous mountainous scenic spots and the development of cultural landscapes in world cultural heritages, the paper has analyzed the value of famous mountainous scenic spots in China and considered that Chinese famous mountainous scenic spots are of rich natural science value and unique aesthetic value, have inherited traditional humane landscape aesthetic value, reflected the philosophical view of "the unity between heaven and human" and profound religious culture, and preserved rich cultural remains, corresponding with the definition and requirement of cultural landscape in world heritages. 展开更多
关键词 CHINESE FAMOUS MOUNTAIN Cultural landscape World HERITAGE scenic spot
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An insight on the mechanism of efficient leaching of vanadium from vanadium shale induced by microwave-generated hot spots 被引量:3
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作者 Sheng Li Yimin Zhang +1 位作者 Yizhong Yuan Pengcheng Hu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期293-302,共10页
Microwave heating can rapidly and uniformly raise the temperature and accelerate the reaction rate.In this paper,microwave heating was used to improve the acid leaching,and the mechanism was investigated via microscop... Microwave heating can rapidly and uniformly raise the temperature and accelerate the reaction rate.In this paper,microwave heating was used to improve the acid leaching,and the mechanism was investigated via microscopic morphology analysis and numerical simulation by COMSOL Multiphysics software.The effects of the microwave power,leaching temperature,CaF_(2) dosage,H_(2)SO_(4) concentration,and leaching time on the vanadium recovery were investigated.A vanadium recovery of 80.66%is obtained at a microwave power of 550 W,leaching temperature of 95℃,CaF_(2) dosage of 5wt%,H_(2)SO_(4) concentration of 20vol%,and leaching time of 2.5 h.Compared with conventional leaching technology,the vanadium recovery increases by 6.18%,and the leaching time shortens by 79.17%.More obvious pulverization of shale particles and delamination of mica minerals happen in the microwave-assisted leaching process.Numerical simulation results show that the temperature of vanadium shales increases with an increase in electric field(E-field).The distributions of E-field and temperature among vanadium shale particles are relatively uniform,except for the higher content at the contact position of the particles.The analysis results of scaleup experiments and leaching experiments indicate high-temperature hot spots in the process of microwave-assisted leaching,and the local high temperature destroys the mineral structure and accelerates the reaction rate. 展开更多
关键词 vanadium shale microwave-assisted leaching hot spots numerical simulation
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Allocation optimization of bicycle-sharing stations at scenic spots 被引量:5
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作者 郭唐仪 张平 +1 位作者 邵飞 刘英舜 《Journal of Central South University》 SCIE EI CAS 2014年第8期3396-3403,共8页
Bicycle-sharing system is considered as a green option to provide a better connection between scenic spots and nearby metro/bus stations. Allocating and optimizing the layout of bicycle-sharing system inside the sceni... Bicycle-sharing system is considered as a green option to provide a better connection between scenic spots and nearby metro/bus stations. Allocating and optimizing the layout of bicycle-sharing system inside the scenic spot and around its influencing area are focused on. It is found that the terrain, land use, nearby transport network and scenery point distribution have significant impact on the allocation of bicycle-sharing system. While the candidate bicycle-sharing stations installed at the inner scenic points, entrances/exits and metro stations are fixed, the ones installed at bus-stations and other passenger concentration buildings are adjustable. Aiming at minimizing the total cycling distance and overlapping rate, an optimization model is proposed and solved based on the idea of cluster concept and greedy heuristic. A revealed preference/stated preference (RP/SP) combined survey was conducted at Xuanwu Lake in Nanjing, China, to get an insight into the touring trip characteristics and bicycle-sharing tendency. The results reveal that 39.81% visitors accept a cycling distance of 1-3 km and 62.50% respondents think that the bicycle-sharing system should charge an appropriate fee. The sttrvey indicates that there is high possibility to carry out a bicycle-sharing system at Xuanwu Lake. Optimizing the allocation problem cluster by cluster rather than using an exhaustive search method significantly reduces the computing amount from O(2^43) to O(43 2). The 500 m-radius-coverage rate for the alternative optimized by 500 m-radius-cluster and 800 m-radius-cluster is 89.2% and 68.5%, respectively. The final layout scheme will provide decision makers engineering guidelines and theoretical support. 展开更多
关键词 bicycle-sharing allocation optimization scenic spot CLUSTER
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Accessibility Comparison and Spatial Differentiation of Xi’an Scenic Spots with Different Modes Based on Baidu Real-time Travel 被引量:5
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作者 WANG Li CAO Xiaoshu +1 位作者 LI Tao GAO Xingchuan 《Chinese Geographical Science》 SCIE CSCD 2019年第5期848-860,共13页
A study of the accessibility of a city’s scenic spots via different travel modes can contribute to optimization of tourism-related transportation while improving tourists’ travel-related satisfaction levels and adva... A study of the accessibility of a city’s scenic spots via different travel modes can contribute to optimization of tourism-related transportation while improving tourists’ travel-related satisfaction levels and advancing tourism. We systematically analyzed the accessibility of 56 scenic spots in Xi’an City, China, via car and public transport travel modes using the real-time travel function of the Baidu Maps API(Application Programming Interface) along with spatial analysis methods and the modal accessibility gap index of scenic spots. We obtained the following results. First, maximum and minimum travel times using public transport exceeded those using cars. Moreover, the accessibility of scenic spots via cars and public transport presented a circular spatial pattern of increasing travel time from the center to the periphery. Contrasting with travel by public transport, car travel showed a clear time-space compression effect. Second, accessibility of the scenic spots via cars and public transport showed some spatial heterogeneity, with no clear advantages of car accessibility in the central urban area. However, advantages of car accessibility were increasingly evident moving from the center to the periphery. Third, whereas the correlation of the modal accessibility gap index of scenic spots in Xi’an with global space was significantly positive, local spatial interdependence was only evident in some inner city areas and in marginal areas. Moreover, spatial heterogeneity was evident in two regions but was insignificant in other areas, indicating that the spatial interdependence of the modal accessibility gap index in most scenic spots was not apparent in terms of the overall effect of public transport routes, road networks, and the distribution of scenic spots. The improvement of public transport coverage in marginal areas and the optimization of public transport routes in central urban areas are essential tasks for improving travel using public transport in the future. 展开更多
关键词 BAIDU REAL-TIME TRAVEL car ACCESSIBILITY public transport ACCESSIBILITY modal ACCESSIBILITY gap scenic spots Xi’an City
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Analysis of Names of Twelve Scenic Spots in Baoding Ancient Lotus Pond Garden in China
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作者 果治 段艳霞 +1 位作者 杨玉梅 魏汉朝 《Journal of Landscape Research》 2012年第4期26-28,共3页
By taking the twelve scenic spots in Ancient Lotus Pond Garden as study objects, they have been introduced and their names have been classified in accordance with allege and symbol nomenclature, linguistic rhetoric no... By taking the twelve scenic spots in Ancient Lotus Pond Garden as study objects, they have been introduced and their names have been classified in accordance with allege and symbol nomenclature, linguistic rhetoric nomenclature, narration and description nomenclature, and emotion-endowing and ambition-expressing nomenclature adopted in related articles. Then, the cultural connotations of these scenic spots have been summarized, and Confucian thought and Taoist thought contained in "Surge Including Pavilion" and "High Principle Tower" have been analyzed. The research is aimed at enlightening modern garden workers through illustrating the connotation of the names of scenic spots, so that they can be inspired in the naming process. 展开更多
关键词 ANCIENT LOTUS POND GARDEN TWELVE scenic spots Analysis of NAMES
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Managing Soil Erosion Potential by Integrating Digital Elevation Models with the Southern China's Revised Universal Soil Loss Equation——A Case Study for the West Lake Scenic Spots Area of Hangzhou,China 被引量:1
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作者 WANG Weiwu 《Journal of Mountain Science》 SCIE CSCD 2007年第3期237-247,共11页
In China, many scenic and tourism areas are suffering from the urbanization that results from physical development of tourism projects, leading to the removal of the vegetative cover, the creation of areas impermeable... In China, many scenic and tourism areas are suffering from the urbanization that results from physical development of tourism projects, leading to the removal of the vegetative cover, the creation of areas impermeable to water, in-stream modifications, and other problems. In this paper, the risk of soil erosion and its ecological risks in the West Lake Scenic Spots (WLSS) area were quantitatively evaluated by integrating the revised universal soil loss equation (RUSLE) with a digital elevation model (DEM) and geographical information system (GIS) software. The standard RUSLE factors were modified to account for local climatic and topographic characteristics reflected in the DEM maps, and for the soil types and vegetation cover types. An interface was created between the Areinfo software and RUSLE so that the level of soil erosion and its ecological risk in the WLSS area could be mapped immediately once the model factors were defined for the area. The results from an analysis using the Areinfo-RUSLE interface showed that the risk value in 93 % of the expanding western part of the WLSS area was moderate or more severe and the soil erosion risk in this area was thus large compared with that in the rest of the area. This paper mainly aimed to increase the awareness of the soil erosion risk in urbanizing areas and suggest that the local governments should consider the probable ecological risk resulting from soil erosion when enlarging and developing tourism areas. 展开更多
关键词 West Lake scenic spots RUSLE model modification GIS digital elevation model ecological risk of soil erosion China
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Entropy Method Based Evaluation for Plant Landscape in Tourist Scenic Spots 被引量:2
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作者 Xunfan SU Wenfeng YANG 《Asian Agricultural Research》 2017年第9期36-39,46,共5页
Taking five scenic spots in southeast region of Tibet as research objects,this paper calculated the weight of plant landscape evaluation system by entropy weight method,and compared the plant landscape in scenic spots... Taking five scenic spots in southeast region of Tibet as research objects,this paper calculated the weight of plant landscape evaluation system by entropy weight method,and compared the plant landscape in scenic spots from aesthetic effect,ecological harmony and service functions. The results show that the rank of the comprehensive attributes from high to low is as follows: Nanyigou,Lulang Forest,Kading Mountain Waterfall,Yarlung Zangbo Grand Canyon,and Basomtso Lake. 展开更多
关键词 Entropy method TIBET scenic spots Plant landscape evaluation
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The effect of activating fluxes on the cathode spots in the activating TIG welding 被引量:1
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作者 黄勇 王伯洋 +4 位作者 郭建航 刘永刚 黄健康 樊丁 余淑荣 《China Welding》 CAS 2023年第1期7-17,共11页
The cathode spots are a common phenomenon in the TIG(tungsten inert gas)welding process.However,it is rarely observed in the activating TIG welding process.This research is mainly focused on the effect of activating f... The cathode spots are a common phenomenon in the TIG(tungsten inert gas)welding process.However,it is rarely observed in the activating TIG welding process.This research is mainly focused on the effect of activating flux on cathode spots in the activating TIG welding.The characteristics and behaviors of cathode spots were investigated in activating TIG welding by the high-speed camera and the spectrograph.Three kinds of oxide(TiO_(2),SiO_(2),MnO_(2))and two halide(MnCl_(2),CaF_(2))activating fluxes are used in the activating TIG welding process.The results show that differ from the TIG welding,the oxide activating flux increases the number of cathode spots and decreases the velocity.The effect is the opposite for the halide activating flux.Moreover,the number of spots no longer varies with the current except TiO2 activating flux.As the temperature of the weld pool surface increases the spot moves away from the center.But this rule is not valid when silica and manganese compounds activating fluxes are used.The variation of cathode spots is caused by the oxide film reformed and the distribution of weld slag.The formation mechanism of cathode spots might be the impact of ions on the cathode surface and the strong electric field formed near the cathode surface. 展开更多
关键词 cathode spots behaviors activating tungsten inert gas welding high-speed photography spectrum
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Research on New Media Marketing Strategy of Quzhou Jianglang Mountain Scenic Spot Based on 4R Marketing Theory
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作者 XU Rui-xia YUAN Zhi-qian 《Sino-US English Teaching》 2023年第8期326-333,共8页
With the increasing popularity of new media,new media marketing plays an increasingly important role in the marketing of tourism scenic spots,bringing a new marketing opportunity to tourism scenic spots.Based on the 4... With the increasing popularity of new media,new media marketing plays an increasingly important role in the marketing of tourism scenic spots,bringing a new marketing opportunity to tourism scenic spots.Based on the 4R theory in marketing theory,this paper takes Quzhou Jianglang Mountain as the research object and finds that the following problems exist in the new media marketing of Quzhou Jianglang Mountain:1.The new media users are not closely enough connected;2.the response to the new media market changes is not fast enough;3.the new media marketing relationship interaction is not timely enough;and 4.the return of new media marketing is not ideal.The new media marketing strategy of Quzhou Jianglang Mountain Scenic Spot is proposed from four perspectives:association,reaction,relationship,and return.Finally,the research on the new media marketing strategy of Quzhou Jianglang Mountain Scenic Spot based on the 4R theory is summarized. 展开更多
关键词 4R theory Quzhou Jianglang Mountain scenic spot new media marketing
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Effects of spot size on the operation mode of Ga As photoconductive semiconductor switch employing extrinsic photoconductivity 被引量:1
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作者 韦金红 李嵩 +5 位作者 陈红 曾凡正 贾成林 付泽斌 葛行军 钱宝良 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期91-99,共9页
To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insul... To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insulating wafer with a thickness of 1 mm,triggered by a 1064-nm extrinsic laser beam with the rectangular spot,has been investigated experimentally.It is found that the variation of the spot size in length and width can act on the different parts of the output waveform integrating the characteristics of the linear and nonlinear modes,and then significantly boosts the PCSS toward different operation modes.On this basis,a two-channel model containing the active and passive parts is introduced to interpret the relevant influencing mechanisms.Results indicate that the increased spot length can peak the amplitude of static domains in the active part to enhance the development of the nonlinear switching,while the extended spot width can change the distribution of photogenerated carriers on both parts to facilitate the linear switching and weaken the nonlinear switching,which have been proved by comparing the domain evolutions under different spot sizes. 展开更多
关键词 GaAs PCSS operation mode spot size on-state performances two-channel model domain evolution
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The Spatial Patterns of Road Traffic Crash Black Spots and Emergency Facilities in Federal Capital City
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作者 Mamman Saba Jibril David Sesugh Aule Badiatu Danladi Garba 《Journal of Geoscience and Environment Protection》 2023年第2期121-134,共14页
This study aimed at determining the spatial patterns of Road Traffic Crash (RTC) black spots, Federal Road Safety Commission (FRSC) zebra points and emergency health care facilities in Federal Capital City (FCC). The ... This study aimed at determining the spatial patterns of Road Traffic Crash (RTC) black spots, Federal Road Safety Commission (FRSC) zebra points and emergency health care facilities in Federal Capital City (FCC). The aim was to provide stakeholders with information that will aid their understanding of accident prone locations and accessible rescue possibilities for accident victims on the roads in FCT. GPS Map 76S Mark (GARMIN) was used to locate and pick coordinates of data in the study area. A total of 16 possible emergency health care facilities, seventy (70) RTC black spots and Five Zebra point locations were obtained from FRSC. ArcGIS 10.0 was used to compute the data by plotting the coordinates to produce maps of the spatial relationship and to carry out Nearest Neighbour Analysis (NNA). The result was further used to determine the spatial patterns of RTC black spots as well as patterns of the emergency facilities. Generally, the result shows that the spatial trend is turning towards dispersion. However, there is less than 1% likelihood that the dispersed patterns could be the result of random chance. It was recommended that, the Federal Road Safety Commission should be staffed with trained professionals that can be responsible for accident data surveillance and analysis using geospatial techniques. 展开更多
关键词 ACCIDENT Black spot EMERGENCY Pattern Spatial Zebra Point
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Storage of Gamma-Glutamyltransferase from Dried Serum Spots: Matrix for Field Based Studies
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作者 Ram Kumar Rizwana Quraishi 《Pharmacology & Pharmacy》 2023年第11期478-481,共4页
Background: Gamma-glutamyltransferase is recognised as a biomarker to assess the harms associated with alcohol misuse. The objective ways to measure GGT in areas lacking central lab facilities are desirable. This stud... Background: Gamma-glutamyltransferase is recognised as a biomarker to assess the harms associated with alcohol misuse. The objective ways to measure GGT in areas lacking central lab facilities are desirable. This study aims to measure GGT from dried serum spots and its storage from dried serum spots. Method: The study was approved by the institutional ethical committee. One hundred and eighty (180) patients were included in the study. Their blood samples were collected. The serum samples were spotted onto filter paper (Whatman 903) dried and stored at 4°C. The GGT levels were measured on the day of collection and at various time periods to assess the effect of storage. All the analysis was performed on SPSS version 21. Result: The GGT levels measured from fresh serum GGT levels mean (SD) 286.5 (539.4) correlated well with their respective dried serum levels 287.18 (538.2) (P = 0.80). The mean recovery of GGT from dried serum was observed to be 103.3%. A sub-sample (n = 12) was stored at 4°C. The dried serum spots were found to be stable at the end of four weeks using repeated measure analysis of variance (ANOVA) (P = 0.39). Conclusion: This method has the potential to be used for epidemiological or field based studies to assess harms associated with alcohol use. 展开更多
关键词 STORAGE GAMMA-GLUTAMYLTRANSFERASE Dried Serum spots
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Quantitative and Comprehensive Prediction of Shale Oil Sweet Spots in Qingshankou Formation, Songliao Basin
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作者 Tiantian Wu Xin Bai +9 位作者 Fei Shang Haiyan Zhou Lan Wang Xuexian Zhou Zhi Zhong Zhi Yang Jinyou Zhang Xinyang Cheng Peiyu Zhang Ruiqian Chen 《Journal of Geoscience and Environment Protection》 2023年第5期290-315,共26页
The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”.... The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”. To accurately identify and optimize the favorable sweet spots of shale oil in Qingshankou Formation, Songliao Basin, the original logging data were preprocessed in this paper. Then the thin mud shale interlayer of Qingshankou Formation was identified effectively by using the processed logging data. Based on the artificial neural network method, the mineral content of mud shale in Qingshankou Formation was predicted. The lithofacies were identified according to the mineral and TOC content. Finally, a three-dimensional (3-D) model of total organic carbon (TOC), vitrinite reflectance (Ro), mineral content, and rock of Qingshankou Formation in Songliao Basin was established to evaluate and predict the favorable sweet spots of shale oil in the study area. The results show that there are a lot of calcareous and siliceous thin interlayers in Qingshankou Formation, and TOC content is generally between 2% and 3%. Ro is the highest in Gulong sag, followed by Sanzhao sag. The lithofacies mainly consists of felsic shale and mixed shale, mainly in the first member of Qingshankou Formation. Comprehensive analysis shows that shale oil development potential is enormous in the eastern part of Sanzhao Sag and the northern part of Gulong Sag. 展开更多
关键词 Songliao Basin Qingshankou Formation Shale Oil Sweet spot Artificial Neural Network
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