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Mapping and resource evaluation of deep high-temperature geothermal resources in the Jiyang Depression,China
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作者 Shaozheng Wang Yaoqi Zhou +5 位作者 Xin Zhang Yangzhou Wang Yonghong Yang Yuehan Shang Yang Chen Xiaoxin Shi 《Energy Geoscience》 EI 2024年第4期142-155,共14页
In China,geothermal resource utilization has mainly focused on resources at shallow and medium depths.Yet,the exploration of deep,high-temperature geothermal resources holds significant importance for achieving the“d... In China,geothermal resource utilization has mainly focused on resources at shallow and medium depths.Yet,the exploration of deep,high-temperature geothermal resources holds significant importance for achieving the“dual carbon”goals and the transition of energy structure.The Jiyang Depression in the Bohai Bay Basin has vast potential for deep,high-temperature geothermal resources.By analyzing data from 2187 wells with temperature logs and 270 locations for temperature measurement in deep strata,we mapped the geothermal field of shallow to medium-deep layers in the Jiyang Depression using ArcGIS and predicted the temperatures of deep layers with a burial depth of 4000 m.Through stochastic modeling and numerical simulation,a reservoir attribute parameter database for favorable deep,high-temperature geothermal areas was developed,systematically characterizing the spatial distribution of geothermal resources within a play fairway of 139.5 km2 and estimating the exploitable deep geothermal resource potential by using the heat storage method and Monte Carlo data analysis.The study reveals that the Fan 54 well block in the Boxing-Jijia region is of prime significance to develop deep,high-temperature geothermal resources in the Jiyang Depression.Strata from the Cenozoic to the Upper Paleozoic are identified as effective cap layers for these deep geothermal resources.The Lower Paleozoic capable of effectively storing thermal energy and possessing an exploitable resource volume up to 127 million tons of standard coal,is identified as a target system for the development of deep high-temperature geothermal resources,providing significant insights for the efficient development of geothermal resources in the Jiyang Depression. 展开更多
关键词 Deep high-temperature geothermal resource Geological modeling resource assessment Lower Paleozoic Jiyang Depression
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A Stacking Machine Learning Model for Student Performance Prediction Based on Class Activities in E-Learning
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作者 Mohammad Javad Shayegan Rosa Akhtari 《Computer Systems Science & Engineering》 2024年第5期1251-1272,共22页
After the spread of COVID-19,e-learning systems have become crucial tools in educational systems worldwide,spanning all levels of education.This widespread use of e-learning platforms has resulted in the accumulation ... After the spread of COVID-19,e-learning systems have become crucial tools in educational systems worldwide,spanning all levels of education.This widespread use of e-learning platforms has resulted in the accumulation of vast amounts of valuable data,making it an attractive resource for predicting student performance.In this study,we aimed to predict student performance based on the analysis of data collected from the OULAD and Deeds datasets.The stacking method was employed for modeling in this research.The proposed model utilized weak learners,including nearest neighbor,decision tree,random forest,enhanced gradient,simple Bayes,and logistic regression algorithms.After a trial-and-error process,the logistic regression algorithm was selected as the final learner for the proposed model.The results of experiments with the above algorithms are reported separately for the pass and fail classes.The findings indicate that the accuracy of the proposed model on the OULAD dataset reached 98%.Overall,the proposed method improved accuracy by 4%on the OULAD dataset. 展开更多
关键词 STACKING e-learning student performance prediction machine learning CLASSIFICATION
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Ethics of Human Resources Management in the Cameroonian Health System, Medical Nomadism and the Ineffectiveness of the Fight against High Blood Pressure
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作者 Jean Ndibi Abanda Anicet Onana Akoa +2 位作者 Désiré Tchoffo Ulrich Dama Pierre Yassa Yoniene 《Health》 2024年第1期9-21,共13页
Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of sk... Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of skills on both qualitative and quantitative levels is one of the essential functions of a health system. To better implement policies of fight against High Blood Pressure (HBP) and other chronic diseases, it is important to establish strategies to retain health personnel. This loyalty requires favorable working conditions and consideration of the contribution-reward couple. Good working conditions are likely to reduce the phenomenon of medical nomadism;conversely, poor HR management can contribute to their exodus towards exotic “green pastures”, thus leading to an additional crisis in the Cameroonian health system. The fight against HBP is a complex, multifaceted and multifactorial reality that requires appropriate management model for all types of resources mainly HR. The main objective of this research is to show the impact of poor management of human resources in Cameroon health system on medical nomadism and the ineffectiveness of the fight against High Blood Pressure. Method: A cross-sectional descriptive survey among five hundred (500) health facilities in the center region of Cameroon has been conducted. A stratified probabilistic technique has been used, and the number of health facilities to be surveyed has been determined using the “sample size estimation table” of Depelteau. The physical questionnaires have been printed and then distributed to data collectors. After data collection, the latter were grouped during processing in Excel sheets. The Chi-square test was used for data with a qualitative value and that of Kolmogorov-Sminorf for data with a quantitative value to assess the normality and reliability of data. The Crochach’s Alpha reliability test allowed us to have a summary of the means and variances and then to search for intragroup correlations between variables. Descriptive analysis was possible with the XLSTAT 2016 software. Results: 43.60% of Health Facilities (HF) managers were unqualified. 82.20% of HF managers have staff in a situation of professional insecurity. They are mainly contractual (49.00), decision-making agents (24.40%), casual agents (08.80). The proportion of unstable personnel is average of 22.00% and very unstable, 12.00%. 展开更多
关键词 ETHICS Human resources Management Cameroonian Health System Medical Nomadism Ineffectiveness High Blood Pressure
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Efficient Intelligent E-Learning Behavior-Based Analytics of Student’s Performance Using Deep Forest Model
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作者 Raed Alotaibi Omar Reyad Mohamed Esmail Karar 《Computer Systems Science & Engineering》 2024年第5期1133-1147,共15页
E-learning behavior data indicates several students’activities on the e-learning platform such as the number of accesses to a set of resources and number of participants in lectures.This article proposes a new analyt... E-learning behavior data indicates several students’activities on the e-learning platform such as the number of accesses to a set of resources and number of participants in lectures.This article proposes a new analytics systemto support academic evaluation for students via e-learning activities to overcome the challenges faced by traditional learning environments.The proposed e-learning analytics system includes a new deep forest model.It consists of multistage cascade random forests with minimal hyperparameters compared to traditional deep neural networks.The developed forest model can analyze each student’s activities during the use of an e-learning platform to give accurate expectations of the student’s performance before ending the semester and/or the final exam.Experiments have been conducted on the Open University Learning Analytics Dataset(OULAD)of 32,593 students.Our proposed deep model showed a competitive accuracy score of 98.0%compared to artificial intelligence-based models,such as ConvolutionalNeuralNetwork(CNN)and Long Short-TermMemory(LSTM)in previous studies.That allows academic advisors to support expected failed students significantly and improve their academic level at the right time.Consequently,the proposed analytics system can enhance the quality of educational services for students in an innovative e-learning framework. 展开更多
关键词 e-learning behavior data student evaluation artificial intelligence machine learning
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Dynamical Artificial Bee Colony for Energy-Efficient Unrelated Parallel Machine Scheduling with Additional Resources and Maintenance
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作者 Yizhuo Zhu Shaosi He Deming Lei 《Computers, Materials & Continua》 SCIE EI 2024年第10期843-866,共24页
Unrelated parallel machine scheduling problem(UPMSP)is a typical scheduling one and UPMSP with various reallife constraints such as additional resources has been widely studied;however,UPMSP with additional resources,... Unrelated parallel machine scheduling problem(UPMSP)is a typical scheduling one and UPMSP with various reallife constraints such as additional resources has been widely studied;however,UPMSP with additional resources,maintenance,and energy-related objectives is seldom investigated.The Artificial Bee Colony(ABC)algorithm has been successfully applied to various production scheduling problems and demonstrates potential search advantages in solving UPMSP with additional resources,among other factors.In this study,an energy-efficient UPMSP with additional resources and maintenance is considered.A dynamical artificial bee colony(DABC)algorithm is presented to minimize makespan and total energy consumption simultaneously.Three heuristics are applied to produce the initial population.Employed bee swarm and onlooker bee swarm are constructed.Computing resources are shifted from the dominated solutions to non-dominated solutions in each swarm when the given condition is met.Dynamical employed bee phase is implemented by computing resource shifting and solution migration.Computing resource shifting and feedback are used to construct dynamical onlooker bee phase.Computational experiments are conducted on 300 instances from the literature and three comparative algorithms and ABC are compared after parameter settings of all algorithms are given.The computational results demonstrate that the new strategies of DABC are effective and that DABC has promising advantages in solving the considered UPMSP. 展开更多
关键词 Artificial bee colony parallel machine scheduling ENERGY additional resource
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Knowledge mapping of research on sustainable utilization of landscape resources:a case study of Guilin National Innovation Demonstration Zone for sustainable development in China
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作者 Xiuxiu Gao Yang Li +1 位作者 Yijue Li Zheng He 《Chinese Journal of Population,Resources and Environment》 2024年第3期326-333,共8页
Worldwide interest has increasingly focused on the sustainable utilization of landscape as a resource in urban areas,emphasizing its ecological,cultural and social significance.This study examines Guilin City,China,as... Worldwide interest has increasingly focused on the sustainable utilization of landscape as a resource in urban areas,emphasizing its ecological,cultural and social significance.This study examines Guilin City,China,as a representative case study due to its rich landscape resources and status as a national innovation demonstration zone for implementing the 2030 Agenda for Sustainable Development.This study uses bibliometric visualization tools like CiteSpace and VOSviewer to analyze research trends from 1980 to 2021 in the Chinese Academic Journal Network Publishing Database(CNKI).The results show increasing academic interest over three stages:initiation(1982-1997),exploration(1998-2004),and diversified development(2005-2021).Contributions are predominantly from local academic and tourism sectors,indicating a strong regional influence;however,relatively weak interinstitutional collaboration occurs,suggesting potential for more integrated research efforts.Primary research is also concentrated within economic disciplines,particularly tourism-related ones.The evolution of research frontiers reveals three main paths:urban development strategies,industrial economic theories and empirical validation,and ecosystem analysis and evaluation.A multidisciplinary approach and stronger collaborative efforts are crucial to enhance research on ecological values and empirical models while supporting evidence-based urban development strategies in Guilin City and comparable cities globally. 展开更多
关键词 Sustainable development Landscape resources Bibliometric analysis Knowledge mapping
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Joint Allocation of Computing and Connectivity Resources in Survivable Inter-Datacenter Elastic Optical Networks
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作者 Yang Tao Li Yang Chen Xue 《China Communications》 SCIE CSCD 2024年第8期172-181,共10页
Inter-datacenter elastic optical networks(EON)need to provide the service for the requests of cloud computing that require not only connectivity and computing resources but also network survivability.In this paper,to ... Inter-datacenter elastic optical networks(EON)need to provide the service for the requests of cloud computing that require not only connectivity and computing resources but also network survivability.In this paper,to realize joint allocation of computing and connectivity resources in survivable inter-datacenter EONs,a survivable routing,modulation level,spectrum,and computing resource allocation algorithm(SRMLSCRA)algorithm and three datacenter selection strategies,i.e.Computing Resource First(CRF),Shortest Path First(SPF)and Random Destination(RD),are proposed for different scenarios.Unicast and manycast are applied to the communication of computing requests,and the routing strategies are calculated respectively.Simulation results show that SRMLCRA-CRF can serve the largest amount of protected computing tasks,and the requested calculation blocking probability is reduced by 29.2%,28.3%and 30.5%compared with SRMLSCRA-SPF,SRMLSCRA-RD and the benchmark EPS-RMSA algorithms respectively.Therefore,it is more applicable to the networks with huge calculations.Besides,SRMLSCRA-SPF consumes the least spectrum,thereby exhibiting its suitability for scenarios where the amount of calculation is small and communication resources are scarce.The results demonstrate that the proposed methods realize the joint allocation of computing and connectivity resources,and could provide efficient protection for services under single-link failure and occupy less spectrum. 展开更多
关键词 computing and connectivity interdatacenter networks joint resource allocation service protection
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Spatial and Temporal Distribution Characteristics of Solar Energy Resources in Tibet
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作者 Yanbo Shen Yang Gao +3 位作者 Yueming Hu Xin Yao Wenzheng Yu Yubing Zhang 《Energy Engineering》 EI 2024年第1期43-57,共15页
The Tibet Plateau is one of the regions with the richest solar energy resources in the world.In the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the regi... The Tibet Plateau is one of the regions with the richest solar energy resources in the world.In the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the region will play an important role.In this study,the gridded solar resource data with 1km resolution in Tibet were obtained by spatial correction and downscaling of SMARTS model.On this basis,the spatial and temporal distribution characteristics of solar energy resources in the region in the past 30 years(1991–2020)are finely evaluated,and the annual global horizontal radiation resource is calculated.The results show that:1)The average annual global horizontal radiation amount in Tibet is 1816 kWh/m^(2).More than 60%of the area belongs to the“Most abundant”(GHI≥1750 kWh/m^(2))area of China’s solar energy resources category A,and nearly 40%belongs to the“Quite abundant”(1400≤GHI<1750)area of China’s solar energy resource category B.2)In space,the solar energy resources in Tibet increased gradually from north to south and from east to west.Lhasa,Central and Eastern Shigatse,Shannan,and Southwestern Ali are the most abundant cities,with a maximum annual radiation level of 2189 kWh/m2.3)In terms of time,the total horizontal radiation in Tibet was the highest in May and the lowest in December.74%of the total area belongs to the“Very stable”(R_(w)≥0.47)area of solar resource stability category A,and 26%belongs to the“stable”(0.36≤R_(w)<0.47)area of solar resource stability category B.Solar energy resources in the region show the characteristics of both strong and stable.Average solar energy resources in the region have shown a fluctuating downward trend over the past 30 years,with an average decline of about 12.86(kWh/m2)per decade.4)In terms of solar radiation resources reaching the earth’s surface,the theoretical total amount of annual horizontal radiation in Tibet is about 240.07 billion tons of standard coal or 222.91 billion kilowatts on average. 展开更多
关键词 TIBET solar resource spatiotemporal distribution
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Conditions for the enrichment of karst hydrothermal resources in Bohai Bay Basin
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作者 Pengwei Li Zhiliang He +2 位作者 Zongquan Hu Ying Zhang Jianyun Feng 《Energy Geoscience》 EI 2024年第1期172-183,共12页
Drilling for karst hydrothermal resources in eastern China has posed challenges,including disparities between the temperature and yield of geothermal water.It is evident that relying solely on geothermal anomalies or ... Drilling for karst hydrothermal resources in eastern China has posed challenges,including disparities between the temperature and yield of geothermal water.It is evident that relying solely on geothermal anomalies or indications of karst reservoirs is inadequate for the exploration of karst hydrothermal resources.This study seeks to elucidate the cause of geothermal sweet spots by analyzing the interplay between geothermal anomalies and karst reservoirs and the underlying geological conditions for karst hydrothermal enrichment.Key findings include:(1)the Bohai Bay Basin has been geologically favorable for the development of karst hydrothermal resources since the Mesozoic era;(2)the karst hydrothermal enrichment varies significantly between the basin’s margin and its interior.On the basin margin,the enrichment is largely driven by groundwater activity and faults,particularly where faults facilitate the upwelling of geothermal water.In contrast,within the basin’s interior,karst hydrothermal resources are predominantly influenced by buried hills and are especially enriched in areas facilitating the discharge of deep geothermal waters. 展开更多
关键词 Buried hill Karst hydrothermal resources Enrichment regularity Bohai bay basin
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Progress in research on the exploration and evaluation of deep geothermal resources in the Fujian-Guangdong-Hainan region,China
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作者 Herong Zheng Jun Luo 《Energy Geoscience》 EI 2024年第2期1-13,共13页
Deep geothermal resources in the Fujian-Guangdong-Hainan region,China,offer significant potential for sustainable energy.The diverse igneous rock formations along the southeast coast present intricate geological chall... Deep geothermal resources in the Fujian-Guangdong-Hainan region,China,offer significant potential for sustainable energy.The diverse igneous rock formations along the southeast coast present intricate geological challenges that impede exploration and evaluation efforts.In this study,we address critical concerns related to the Fujian-Guangdong-Hainan region's deep geothermal resources,encompassing heat source composition,formation conditions,strategic favorable areas,and exploration directions.Our methods involve the analysis of regional geothermal reservoirs and cap rocks.Major findings include:the primary heat sources in the Fujian-Guangdong-Hainan region consist of the radioactive heat generation from granites in the crust,heat conduction in the mantle,and,in specific areas like Yangjiang and Shantou,melts within the middle and lower crust;the deep,high-temperature geothermal resources in the region predominantly reside in basins'depressed areas.These areas are characterized by the confluence of triple heat sources:heat from the Earth's crust,mantle,and other supplementary sources;our analysis led to the identification of three strategic areas favorable for deep geothermal resources in the Fujian-Guangdong-Hainan region.These are the Beibu Gulf Basin's continental area,the Yuezhong Depression,and the Fuzhou-Zhangzhou area. 展开更多
关键词 Deep geothermal resources Geology of geothermal energy Strategic selection
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Enhancing transboundary natural tourism resources governance:unveiling the spatial pattern and its influencing factors
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作者 ZHANG Shengrui ZHANG Tongyan +1 位作者 JU Hongrun WANG Yingjie 《Journal of Mountain Science》 SCIE CSCD 2024年第3期973-986,共14页
Tourism resources that span provincial boundaries in China play a pivotal role in regional development,yet effective governance poses persistent challenges.This study addresses this issue by constructing a comprehensi... Tourism resources that span provincial boundaries in China play a pivotal role in regional development,yet effective governance poses persistent challenges.This study addresses this issue by constructing a comprehensive database of transboundary natural tourism resources(TNTR)through amalgamation of diverse data sources.Utilizing the Getis-Ord Gi^(*),kernel density estimation,and geographical detectors,we scrutinize the spatial patterns of TNTR,focusing on both named and unnamed entities,while exploring the influencing factors.Our findings reveal 7883 identified TNTR in China,with mountain tourism resources emerging as the predominant type.Among provinces,Hunan boasts the highest count,while Shanghai exhibits the lowest.Southern China demonstrates a pronounced clustering trend in TNTR distribution,with the spatial arrangement of biological landscapes appearing more random compared to geological and water landscapes.Western China,characterized by intricate terrain,exhibits fewer TNTR,concurrently unveiling a significant presence of unnamed natural tourism resources.Crucially,administrative segmentation influences TNTR development,generating disparities in regional goals,developmental stages and intensities,and management approaches.In response to these variations,we advocate for strengthening the naming of the unnamed transboundary tourism resources,constructing a geographic database of TNTR for government and establishing a collaborative management mechanism based on TNTR database.Our research contributes to elucidating the intricate landscape of TNTR,offering insights for tailored governance strategies in the realm of cross-provincial tourism resource management. 展开更多
关键词 Transboundary natural tourism resources(TNTR) Spatial difference Spatial autocorrelation Governance optimization China
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Investigation and analysis of vascular plant resources and diversity in Wuyi Mountain,Fujian Province
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作者 Peiying Chen Ruru Xiong +14 位作者 Jun Yuan Minglong Huang Zhuo Tao Bowen Zhang Fanglin Luo Lisha Liu Qian Wang You Zhou Haofan Zhang Zijie Wei Jie Yang Jiangang Chen Kui Wu Anhua Wang Jingming Jia 《Asian Journal of Traditional Medicines》 2024年第1期26-33,共8页
Wuyi Mountain,located in the north of Fujian Province,China,is renowned for its abundant medicinal plant resources.In July 2014,the 8th(second team)of Shenyang Pharmaceutical University’s Chinese Medicine Resources S... Wuyi Mountain,located in the north of Fujian Province,China,is renowned for its abundant medicinal plant resources.In July 2014,the 8th(second team)of Shenyang Pharmaceutical University’s Chinese Medicine Resources Scientific Expedition Team conducted field investigation in the area.Through specimen collection and extensive literature review,the team identified and analyzed 223 vascular plant species from 175 genera and 85 families.The most dominant families were Compositae and Rosaceae,and perennial herbs were the predominant species,accounting for 44.39%of the total species identified.Notably,we documented five precious and rare medicinal plants unique to Wuyi Mountain.This study updates the database of plant resources and diversity in the region,providing a valuable reference for future studies.Finally,we put forward some suggestions to enhance the conservation and sustainable utilization of Wuyi Mountain’s plant resources. 展开更多
关键词 plant resources BIODIVERSITY MEDICINAL protection and utilization resource survey Fujian Province
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Carrying Capacity and Coupling Coordination of Water and Land Resources Systems in Arid and Semi-arid Areas: A Case Study of Yulin City, China
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作者 ZHANG Qianxi CAO Zhi +1 位作者 WANG Yongsheng HUANG Yijia 《Chinese Geographical Science》 SCIE CSCD 2024年第5期931-950,共20页
Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as... Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as a case study and employing the Criteria Importance Through Intercriteria Correlation(CRITIC)method,a modified model of coupling degree was developed to evaluate the car-rying capacity of water and land resources systems endowment and utilization,as well as their coupling coordination degree from 2013 to 2020.Our findings indicate that the water and land resources of Yulin are diminishing due to declines in agriculture,higher industrial water use,and wetland shrinkage.However,reallocating domestic water for ecological sustainability and reducing sloping farmland can mitigate this trend of decline.Temporally,as the coupling coordination between water and land resources system endowment in Yulin continuously improved,the coupling coordination between water and land resources system utilization first decreased and then in-creased with 2016 as the turning point.Spatially,the carrying capacity of water and land resources systems,the coupling coordination degree between water and land resources system endowment,and the coupling coordination degree between water and land resources system utilization in Yulin exhibited the same pattern of being higher in the six northern counties than in the six southern counties.Improving the water resources endowment is vital for the highly efficient use of water and land resources. 展开更多
关键词 water and land resources systems carrying capacity coupling coordination human-earth system sustainable development Yulin City China
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A Brief Analysis of Ranunculaceae Family Resources Based on Yu Tuo Ben Cao
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作者 Hongye YIN Namucuo Longzhuduojie 《Medicinal Plant》 2024年第1期41-44,共4页
[Objectives]To facilitate the rational use and timely protection of the Tibetan medicinal plant resources to count and reorganize Tibetan medicines recorded in Yu Tuo Ben Cao.[Methods]Based on literature research and ... [Objectives]To facilitate the rational use and timely protection of the Tibetan medicinal plant resources to count and reorganize Tibetan medicines recorded in Yu Tuo Ben Cao.[Methods]Based on literature research and data analysis,this paper analyzed the plant genera,and their habitat characteristics and the main types of diseases.[Results]Yu Tuo Ben Cao contains 191 kinds of botanicals,of which Ranunculaceae has the largest number of 11 genera and 25 species,with a wide distribution of habitats and 5 categories,and the main therapeutic efficacy covers 16 fields.[Conclusions]As a part of Yu Tuo Ben Cao,Tibetan medicines of Ranunculaceae have great research value because of their variety,large number,wide distribution,and diverse uses. 展开更多
关键词 Yu Tuo Ben Cao Plant resources RANUNCULACEAE
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Securing offshore resources development:A mathematical investigation into gas leakage in long-distance flexible pipes
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作者 Xiang-An Lu Liang-Liang Jiang +1 位作者 Jian-Sheng Zhang Min-Gui Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2734-2744,共11页
Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development.Under high pressure conditions,small molecular components of natural gas dissolve into the polymer inner liner of the flexib... Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development.Under high pressure conditions,small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space,incurring annular pressure build-up and/or production of acidic environment,which poses serious challenges to the structure and integrity of the flexible pipes.Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature,annular structure,external temperature.In a long-distance gas flexible pipe,moreover,gas permeation exhibits non-uniform features,and the gas permeated into the annular space flows along the metal gap.To assess the complex gas transport behavior in long-distance gas flexible pipes,a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes,the diffusion of gas in the inner liner,and the gas seepage in the annular space under varying permeable properties of the annulus.In addition,the effect of a variable temperature is accounted.A numerical calculation method is accordingly constructed to solve the coupling mathematical equations.The annular permeability was shown to significantly influence the distribution of annular pressure.As permeability increases,the annular pressure tends to become more uniform,and the annular pressure at the wellhead rises more rapidly.After annular pressure relief followed by shut-in,the pressure increase follows a convex function.By simulating the pressure recovery pattern after pressure relief and comparing it with test results,we deduce that the annular permeability lies between 123 and 512 m D.The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources. 展开更多
关键词 Offshore resources development Transport security Long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation
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Analysis of vascular plant resources and diversity in Liupan Mountains of Ningxia Province,China
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作者 Dongdong Wang Minli Ruan +1 位作者 Jingming Jia Anhua Wang 《Asian Journal of Traditional Medicines》 2024年第5期266-274,共9页
Liupan Mountains are situated in the south of Ningxia Hui Autonomous Region and east of Gansu Province.This area is rich in forests and vegetation.After field investigation,literature review and specimen identificatio... Liupan Mountains are situated in the south of Ningxia Hui Autonomous Region and east of Gansu Province.This area is rich in forests and vegetation.After field investigation,literature review and specimen identification,the plant resources and diversity of Liupan Mountains were studied by the 4th Shenyang Pharmaceutical University Chinese Medicine Resources Scientific Expedition Team.There were 161 species of vascular plants belonging to 60 families and 119 genera collected from July to August 2010 in this area.Among them,the dominant families are Campanulaceae,Ranunculaceae,Orobanchaceae,Asparagaceae,Fabaceae,Rosaceae and Asteraceae,with 6,7,8,8,10,10,and 22 species,respectively.Although representing only 11.7%of the total number of families,these families had a species occupancy rate of over 44.1%.At the genus level,Pedicularis is the most dominant genus with 6 species,while 92 genera contain only 1 species,accounting for 77.3%of the total number of genera.In a word,our research has updated the plant resources and diversity in Liupan Mountains.Furthermore,by providing practical and meaningful suggestions for strengthening the protection and utilization of plant resources in Liupan Mountains,our research is of great significance for maintaining the diverse ecosystem in this area. 展开更多
关键词 plant resources DIVERSITY Liupan Mountains
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Efficient utilization of ecological and cultural-tourism resources:Taking Guangzhou Cultural Park as an example
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作者 XU Shu-sheng SUN Qing-yang CHEN Mian-run 《Ecological Economy》 2024年第3期278-289,共12页
Land space is precious resource and carrier of various economic activities.Ecosystem Product Value Realization and Cultural Tourism is new economic growth point for green and low-carbon development.It is necessary to ... Land space is precious resource and carrier of various economic activities.Ecosystem Product Value Realization and Cultural Tourism is new economic growth point for green and low-carbon development.It is necessary to study how to intensively and efficiently utilize ecological and cultural-tourism resources under"Three zones three lines for land use"(3Z3L),which is basic land space planning policy.However,there are few research and cases due to difficulties of interdisciplinary research.This article adopts the methods of policies research,graphic analysis,and visiting,to study efficient utilization of ecological and cultural-tourism resources.This study found that the development of land spaces of ecology,agriculture,and urban areas is 3D trend,multi-purpose resource utilization can be achieved by improving the utilization efficiency of 3D space and differentiating spatial utilization in different periods.Taking Guangzhou Cultural Park as an example,the research object has improved the efficiency of ecological and cultural-tourism resource utilization by its managements and technology,such as“house under the tree,tree inside the house”.However,there are shortcomings just as planning and protection policies with it.We proposed to optimize the spatial planning and regulations,and improve the protection of overlapping areas of 3Z3L by planning and regulations,improve the utilization efficiency of ecological and cultural-tourism space,meet the urban young people's multiple needs such as culture and ecology in 3D space,use new technologies to improve ecological services quality such as biological methods,strengthen the coordination of multiple management departments with the concept of nature based solutions,develop the“Reversed Transmission Effect”,keep the boundary of urban development strictly. 展开更多
关键词 culture-tourism three zones three lines intensive utilization of resources
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Analysis of plant resources and diversity in Shennongjia Area of Hubei Province,China
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作者 Terigen Bao Min Li +1 位作者 Jingming Jia Anhua Wang 《Asian Journal of Traditional Medicines》 2024年第2期66-87,共22页
Shennongjia Area is located in northwest of Hubei Province with Shennongding,the highest peak(3105.4 m above sea level)in central China.The unique geographical location and complex terrain of this region make it rich ... Shennongjia Area is located in northwest of Hubei Province with Shennongding,the highest peak(3105.4 m above sea level)in central China.The unique geographical location and complex terrain of this region make it rich in plant resources.After field investigation,th literature review,and specimen identification,the 7 Shenyang Pharmaceutical University Chinese Medicine Resources Scientific Expedition Team studied the plant resources and diversity of Shennongjia Area.454 species of vascular plants belonging to 106 families and 275 genera were collected from July to August in 2013.The dominant families are Lamiaceae,Ranunculaceae,Rosaceae,and Asteraceae,with 20,21,37 and 48 species respectively.At the genus level,Rubus is the dominant one with 11 species.3 species of national first-class protective plants,13 species of“Huan yang yao”and 36 species of“Qi yao”were collected.In all,our research has updated the plant recources and diversity in Shennongjia Area.Furthermore,by putting forward practical and meaningful suggestions on strengthening the protection and utilization of plant resources in Shennongjia Area,our research will help to protect the diverse ecosystem there. 展开更多
关键词 plant resources DIVERSITY medicinal use Shennongjia Area
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Defining Cities by Water: Addressing Capital Misallocation in a Race to Conserve Resources
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作者 Yao Peng Li Jinze 《China Economist》 2024年第1期86-102,共17页
As part of its efforts to promote a sustainable and high-quality development,China has pledged to reduce water consumption and create a water-efficient society.On the basis of identifying the institutional root causes... As part of its efforts to promote a sustainable and high-quality development,China has pledged to reduce water consumption and create a water-efficient society.On the basis of identifying the institutional root causes of excessive capital allocation and excessive water consumption in China’s water-intensive industrial sectors,this study elaborates how the national water-efficient cities assessment contributes to optimized capital allocation.Our research shows that national water-efficient cities assessment has motivated local governments to compete for water efficiency.To conserve water,local governments regulated the entry and exit of water-intensive enterprises,discouraged excessive investments in water-intensive sectors,and phased out obsolete water-intensive capacities within their jurisdictions.This approach has resulted in mutually beneficial outcomes,including improved allocation of capital,enhanced water efficiency,and reduced emissions.This paper offers policy recommendations for establishing a water-efficient society throughout the 14^(th) Five-Year Plan(2021-2025)period by presenting empirical evidence on the policy effects of resource efficiency evaluation. 展开更多
关键词 Competitive evaluation for resource efficiency national water-efficient cities assessment capital misallocation water efficiency emissions abatement
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A Pre-Selection-Based Ant Colony System for Integrated Resources Scheduling Problem at Marine Container Terminal
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作者 Rong Wang Xinxin Xu +2 位作者 Zijia Wang Fei Ji Nankun Mu 《Computers, Materials & Continua》 SCIE EI 2024年第8期2363-2385,共23页
Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation pe... Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation performance of MCT.To solve the practical resource scheduling problem(RSP)in MCT efficiently,this paper has contributions to both the problem model and the algorithm design.Firstly,in the problem model,different from most of the existing studies that only consider scheduling part of the resources in MCT,we propose a unified mathematical model for formulating an integrated RSP.The new integrated RSP model allocates and schedules multiple MCT resources simultaneously by taking the total cost minimization as the objective.Secondly,in the algorithm design,a pre-selection-based ant colony system(PACS)approach is proposed based on graphic structure solution representation and a pre-selection strategy.On the one hand,as the RSP can be formulated as the shortest path problem on the directed complete graph,the graphic structure is proposed to represent the solution encoding to consider multiple constraints and multiple factors of the RSP,which effectively avoids the generation of infeasible solutions.On the other hand,the pre-selection strategy aims to reduce the computational burden of PACS and to fast obtain a higher-quality solution.To evaluate the performance of the proposed novel PACS in solving the new integrated RSP model,a set of test cases with different sizes is conducted.Experimental results and comparisons show the effectiveness and efficiency of the PACS algorithm,which can significantly outperform other state-of-the-art algorithms. 展开更多
关键词 resource scheduling problem(RSP) ant colony system(ACS) marine container terminal(MCT) pre-selection strategy
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