As an important geothermal resource, hot dry rock （HDR） reserves have been studied in many countries. HDR resources in China have huge capacity and have become one of the most important resources for the potential r...As an important geothermal resource, hot dry rock （HDR） reserves have been studied in many countries. HDR resources in China have huge capacity and have become one of the most important resources for the potential replacement of fossil fuels. However, HDR resources are difficult to develop and utilise. Technologies for use with HDR, such as high-temperature drilling, reservoir characterisation, reservoir fracturing, microseismic monitoring and high-temperature power stations, originate from the field of oil and drilling. Addressing how to take advantage of these developed technologies is a key factor in the development of HDR reserves. Based on the thermal crustal structure in China, HDR resources can be divided into four types： high radioactive heat production, sedimentary basin, modern volcano and the inner-plate active tectonic belt. The prospective regions of HDR resources are located in South Tibet, West Yunnan, the southeast coast of China, Bohai Rim, Songliao Basin and Guanzhong Basin. The related essential technologies are relatively mature, and the prospect of HDR power generation is promising. Therefore, analysing the formation mechanisms of HDR resources and promoting the transformation of technological achievements, large-scale development and the utilisation of HDR resources can be achieved in China.展开更多
This paper summarizes the distribution and production layout of the major mineral resources in China,including coal,iron ore,copper and bauxite,from a national perspective.It also identifies the incompatibility betwee...This paper summarizes the distribution and production layout of the major mineral resources in China,including coal,iron ore,copper and bauxite,from a national perspective.It also identifies the incompatibility between the mineral resources distribution and regional economic development.Significant issues with China's mineral resource industry cause challenges for the sustainable development of both the mining industry and the national socio-economy.The sustainability of regional mineral resources and the environmental pollution by mining in the western China were also analyzed.Results show that the distribution of China's mineral resources is misaligned with its regional layout of economic development.China's mineral resources have been over-exploited,and the mineral resources production in the eastern China is unsustainable.The continuously expanding production of mineral resources in the western China has heavily endangered the ecological environment.We propose strategies to boost the sustainable development of mineral resources,including measures to accelerate economic development and enhance the sustainability of domestic mineral resources.We also offer suggestions for scientifically planning the mineral resource prospecting and exploitation and regional economic layout,as well as for proactively undertaking industry transfer in the eastern China and raising the environmental benchmark requirements for the mineral industry in the central and western China.展开更多
Service and information resources are two kinds of major shared resources in virtual enterprises, where, service resources include third party’s service resources and enterprise’s legacy service resources,and inform...Service and information resources are two kinds of major shared resources in virtual enterprises, where, service resources include third party’s service resources and enterprise’s legacy service resources,and information resources include database resources and file resources. Since service and information resources have distributed, autonomic, remotely bound as well as some other similar characteristics, an implementation mechanism on managing shared resources based on UDDI are presented. XML instances are used to describe resources authorization information, WSDL based special XML instance represents information resource metadata, and these XML instances are referenced by tModel for realizing the purpose of managing shared resources metadata based on UDDI.展开更多
The quantum key distribution （QKD） allows two parties to share a secret key by typically making use of a one-way quantum channel. Howevery the two-way QKD has its own unique advantages, which means the two-way QKD h...The quantum key distribution （QKD） allows two parties to share a secret key by typically making use of a one-way quantum channel. Howevery the two-way QKD has its own unique advantages, which means the two-way QKD has become a focus recently. To improve the practieM performance of the two-way QKD, we present a security analysis of a two-way QKD protocol based on the decoy method with heralded single-photon sources （HSPSs）. We make use of two approaches to calculate the yield and the quantum bit error rate of single-photon and two-photon pulses. Then we present the secret key generation rate based on the GLLP formula. The numerical simulation shows that the protocol with HSPSs has an advantage in the secure distance compared with weak coherent state sources. In addition, we present the final secret key by considering the statistical fluctuation of the yield generation rate of the LM05 protocol with finite resources and the error rate.展开更多
Unconventional hydrocarbon resources, which are only marginally economically explored and developed by traditional methods and techniques, are different from conventional hydrocarbon resources in their accumulation me...Unconventional hydrocarbon resources, which are only marginally economically explored and developed by traditional methods and techniques, are different from conventional hydrocarbon resources in their accumulation mechanisms, occurrence states, distribution models, and exploration and development manners. The types of unconventional hydrocarbon are controlled by the evolu- tion of the source rocks and the combinations of different types of unconventional reservoirs. The fundamental dis- tinction between unconventional hydrocarbon resources and conventional hydrocarbon resources is their non- buoyancy-driven migration. The development of the micro- to nano-scale pores results in rather high capillary resis- tance. The accumulation mechanisms of the unconven- tional and the conventional hydrocarbon resources are also greatly different. In conventional hydrocarbon resources, oil and gas entrapment is controlled by reservoir-forming factors and geological events, which is a dynamic balance process; while for unconventional hydrocarbon resources, the gas content is affected by the temperature and pressure fields, and their preservation is crucial. Unconventional and conventional hydrocarbons are distributed in an orderly manner in subsurface space, having three distribution models of intra-source rock, basin-centered, and source rock interlayer. These results will be of great significance to unconventional hydrocarbon exploration.展开更多
Taking an industrial park as an example,this study aims to analyze the characteristics of a distribution network that incorporates distributed energy resources(DERs).The study begins by summarizing the key features of...Taking an industrial park as an example,this study aims to analyze the characteristics of a distribution network that incorporates distributed energy resources(DERs).The study begins by summarizing the key features of a distribution network with DERs based on recent power usage data.To predict and analyze the load growth of the industrial park,an improved back-propagation algorithm is employed.Furthermore,the study classifies users within the industrial park according to their specific power consumption and supply requirements.This user segmentation allows for the introduction of three constraints:node voltage,wire current,and capacity of DERs.By incorporating these constraints,the study constructs an optimization model for the distribution network in the industrial park,with the objective of minimizing the total operation and maintenance cost.The primary goal of these optimizations is to address the needs of DERs connected to the distribution network,while simultaneously mitigating their potential adverse impact on the network.Additionally,the study aims to enhance the overall energy efficiency of the industrial park through more efficient utilization of resources.展开更多
The metamorphosed sedimentary type of iron deposits（BIF） is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Caraj...The metamorphosed sedimentary type of iron deposits（BIF） is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Carajas in Brazil, Hamersley in Australia, Kursk in Russia, Central Province of India and Anshan-Benxi in China. Subordinated types of iron deposits are magmatic, volcanic-hosted and sedimentary ones. This paper briefly introduces the geological characteristics of major super-large iron ore clusters in the world. The proven reserves of iron ores in China are relatively abundant, but they are mainly low-grade ores. Moreover, a considerate part of iron ores are difficult to utilize for their difficult ore dressing, deep burial or other reasons. Iron ore deposits are relatively concentrated in 11 metallogenic provinces（belts）, such as the Anshan-Benxi, eastern Hebei, Xichang-Central Yunnan Province and middle-lower reaches of Yangtze River. The main minerogenetic epoches vary widely from the Archean to Quaternary, and are mainly the Late Archean to Middle Proterozoic, Variscan, and Yanshanian periods. The main 7 genetic types of iron deposits in China are metamorphosed sedimentary type（BIF）, magmatic type, volcanic-hosted type, skarn type, hydrothermal type, sedimentary type and weathered leaching type. The iron-rich ores occur predominantly in the skarn and marine volcanic-hosted iron deposits, locally in the metamorphosed sedimentary type（BIF） as hydrothermal reformation products. The theory of minerogenetic series of mineral deposits and minerogenic models has applied in investigation and prospecting of iron ore deposits. A combination of deep analyses of aeromagnetic anomalies and geomagnetic anomalies, with gravity anomalies are an effective method to seeking large and deep-buried iron deposits. China has a relatively great oresearching potential of iron ores, especially for metamorphosed sedimentary, skarn, and marine volcanic-hosted iron deposits. For the lower guarantee degree of iron and steel industry, China should give a trading and open the foreign mining markets.展开更多
This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously a...This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.展开更多
The paradigm shift from a coal-based power system to a renewable-energy-based power system brings more challenges to the supply-demand balance of the grid.Distributed energy resources(DERs),which can provide operating...The paradigm shift from a coal-based power system to a renewable-energy-based power system brings more challenges to the supply-demand balance of the grid.Distributed energy resources(DERs),which can provide operating reserve to the grid,are regarded as a promising solution to compensate for the power fluctuation of the renewable energy resources.Small-scale DERs can be aggregated as a virtual power plant(VPP),which is eligible to bid in the operating reserve market.Since the DERs usually belong to different entities,it is important to investigate the VPP operation framework that coordinates the DERs in a trusted man-ner.In this paper,we propose a blockchain-assisted operating reserve framework for VPPs that aggregates various DERs.Considering the heterogeneity of various DERs,we propose a unified reserve capacity evaluation method to facilitate the aggregation of DERs.By considering the mismatch between actual available reserve capacity and the estimated value,the performance of VPP in the operating reserve market is improved.A hardware-based experimental system is developed,and numerical results are presented to demonstrate the effectiveness of the proposed framework.展开更多
The distribution of resources is the basis of safety management.Based on thesystematic analysis of a resource distribution system affecting the level of safety,the bestdistribution proportion between safety activities...The distribution of resources is the basis of safety management.Based on thesystematic analysis of a resource distribution system affecting the level of safety,the bestdistribution proportion between safety activities and production and best resources distributionproportion among the various links of security activities are presented.Moreover,itis stated that the distribution of resources law needs to be researched deeply in practicalwork to achieve optimization of safety management practice.展开更多
In this study,the resource distribution,morphological characteristics,artificial cultivation and market circulation of Paris Polyphylla var.yunnanensis and its polygerm varieties in Yunnan were investigated by referri...In this study,the resource distribution,morphological characteristics,artificial cultivation and market circulation of Paris Polyphylla var.yunnanensis and its polygerm varieties in Yunnan were investigated by referring to the research literature,field investigation and our planting experience.It is found that P.polyphylla var.yunnanensis is widely distributed in Yunnan Province,realizing large-scale artificial cultivation,while the wild resources of polygerm varieties are almost on the verge of extinction and are in urgent need of protection.展开更多
Geothermal resources have a very broad development prospect owing to their clean nature;accurate evaluation of their potential is an important basis for the realization of fine zoning and large-scale efficient develop...Geothermal resources have a very broad development prospect owing to their clean nature;accurate evaluation of their potential is an important basis for the realization of fine zoning and large-scale efficient development.Here,a geothermal evaluation system is established based on reservoir,cap-rock,transportation-system,heat-source,and water-source data.The entropy weight Technique Order Preference by Similarity to an Ideal Solution(TOPSIS)and Analytic Hierarchy Process-Technique Order Preference by Similarity to an Ideal Solution(AHPTOPSIS)methods are used to evaluate geothermal resources in Eryuan County,and the evaluation results are superimposed with equal weights,and combined with the Moran index,to determine the geothermal exploration potential.Our results show that geothermal resources in Eryuan County are abundant,being concentrated in Liantie Township,Qiaohou Town,junction of Sanying and Cibihu towns,and junction of Fengyu and Yousuo towns.The Moran index indicates that there is significant geothermal accumulation,with high geothermal values mainly distributed around the water system.Three types of geothermal models are established based on control factors.The first one is controlled by the combination of reservoir and cap rock,while the second one is controlled by heat source and the third one is controlled by the combination of reservoir and cap rock and heat source.The junctions of Sanying and Cibihu towns,and Fengyu and Yousuo towns,are evaluated to have high geothermal potential,and these may become the next favorable directions for geothermal exploration in Eryuan County.展开更多
The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,dist...The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,distributed renewable resources,and data-driven intelligence,have emerged as the backbone of this evolution.This convergence,however,introduces unprecedented complexities in resilience,security,stability,and market operation.This special issue presents five pivotal studies addressing these interconnected challenges,offering novel methodologies and insights to advance the efficiency,resilience,and sustainability of modern power systems.展开更多
Dear Editor,This letter deals with distributed resource allocation(DRA)over multiple interacting coalitions,where conflicts of interest may arise due to the relevance of one coalition’s decision to other coalitions’...Dear Editor,This letter deals with distributed resource allocation(DRA)over multiple interacting coalitions,where conflicts of interest may arise due to the relevance of one coalition’s decision to other coalitions’benefits.To address this challenge,a new model called intra-independent resource allocation game(IIRAG)is formulated under the framework of multi-coalition games.A new DRA algorithm is developed,which draws on techniques of variable replacement and leaderfollowing consensus.The proposed algorithm ensures linear convergence of the collective decision to the Nash equilibrium(NE)of the IIRAG,as well as satisfaction of the resource constraint throughout the iteration process.Numerical simulations validate the effectiveness of the proposed approach.展开更多
The proliferation of distributed and renewable energy resources introduces additional operational challenges to power distribution systems.Transactive energy management,which allows networked neighborhood communities ...The proliferation of distributed and renewable energy resources introduces additional operational challenges to power distribution systems.Transactive energy management,which allows networked neighborhood communities and houses to trade energy,is expected to be developed as an effective method for accommodating additional uncertainties and security mandates pertaining to distributed energy resources.This paper proposes and analyzes a two-layer transactive energy market in which houses in networked neighborhood community microgrids will trade energy in respective market layers.This paper studies the blockchain applications to satisfy socioeconomic and technological concerns of secure transactive energy management in a two-level power distribution system.The numerical results for practical networked microgrids located at IllinoisTech−Bronzeville in Chicago illustrate the validity of the proposed blockchain-based transactive energy management for devising a distributed,scalable,efficient,and cybersecured power grid operation.The conclusion of the paper summarizes the prospects for blockchain applications to transactive energy management in power distribution systems.展开更多
Catering in scenic areas is an important part of tourist experiences,yet the existing research on catering resources mainly focuses on tourist satisfaction and resource development,with limited analysis on the impact ...Catering in scenic areas is an important part of tourist experiences,yet the existing research on catering resources mainly focuses on tourist satisfaction and resource development,with limited analysis on the impact of catering resources distribution on tourists’visiting willingness.Thus,based on case analysis,surveys and data analysis,this study selected Mount Tai Scenic Area as the research object to conduct an in-depth investigation on the impact of the distribution of catering resources on tourists’visiting willingness,which identified many challenges faced by the distribution of catering resources in the scenic area and their underlying causes,finding that while there were rich varieties and concentrated catering options in high-traffic areas with strong tourists’visiting willingness,significant gaps remained in locations with weak tourists’visiting willingness.Furthermore,the overall catering offerings in Mount Tai Scenic Area demonstrated a notable deficiency in food products that authentically integrate with Mount Tai’s distinctive cultural heritage.To address such issues,improvement strategies were proposed for the development of catering resources in Mount Tai Scenic Area,including spatial development and integration,exploration of cultural connotations,and enhancement of tourism value,which provided insights for refining management of catering resources in forest park scenic spot,optimizing catering services,and enhancing the tourism experience of tourists.展开更多
64 species （including 5 varieties）, 30 genera and 24 families of the edible ferns in Guizhou are preliminartiy confirmed, according to the combination of spot investigation and refereuce analySis：the species, gener...64 species （including 5 varieties）, 30 genera and 24 families of the edible ferns in Guizhou are preliminartiy confirmed, according to the combination of spot investigation and refereuce analySis：the species, genera and families account for 8.13%, 19.74% and 44.44% of ferns in Guizhou, respectively. The floristic composition characters and resource distribution of 23 kinds of the edible ferns in Guizhou are described.展开更多
Monthly fishery survey data of the small yellow croaker Larimichthys polyactis in the southern Yellow Sea from2003 and 2013 were employed to evaluate the variation in the resource distribution and biological character...Monthly fishery survey data of the small yellow croaker Larimichthys polyactis in the southern Yellow Sea from2003 and 2013 were employed to evaluate the variation in the resource distribution and biological characteristics（especially body length and sex ratio） in the population on a decadal scale.The results indicated that the small yellow croaker migrated from the Shawai fishing ground to the Dasha fishing ground in spring and was mainly distributed in the central and western parts of the Dasha fishing ground in April and May.Larimichthys polyactis in the Dasha fishing ground migrated eastward to offshore wintering grounds in autumn and reached the central Dasha fishing ground in October and November.The small yellow croaker entered the western waters of the Shawai fishing ground in winter.A large number of age 0＋ fish occurred in the Shawai and Jiangwai fishing grounds in October of 2003 and 2013.The body lengths of the spawning stock and wintering stock in 2013 were larger than those in 2003,and the monthly sex ratios（female to male） were significantly less than 1 in both years.The monthly distribution of this fish in the southern Yellow Sea was consistent with a previous finding that ＂the stock migrated between the wintering grounds in the west of Jeju Island and the Lüsi spawning grounds＂ but tended to move more northward,with the spawning grounds extending outward.In the past decade,body length variation experienced a decline after an increase,rather than a steady decrease.The sex ratio in the single-stick stow net showed a tendency to increase over the decade,but was either less than or more than 1 depending on the fishing gear;therefore,further studies should be conducted to determine the sex structure.展开更多
Brachystemma calycinum D. Don as an important rare medicinal plant, the market prospect is very promising. In this paper, the resource distribution, ecological environment, community structure, domestication of wild c...Brachystemma calycinum D. Don as an important rare medicinal plant, the market prospect is very promising. In this paper, the resource distribution, ecological environment, community structure, domestication of wild cultivar and market demand and status of Brachystemma calycinum were systematically studied, so as to provide a basis for resource development and utilization.展开更多
基金funded by the geological survey program of China Geology Survey(No.12120113078100)program of Chinese Academy of Engineering(The strategic research on the utilization of geothermal resources in China)
文摘As an important geothermal resource, hot dry rock （HDR） reserves have been studied in many countries. HDR resources in China have huge capacity and have become one of the most important resources for the potential replacement of fossil fuels. However, HDR resources are difficult to develop and utilise. Technologies for use with HDR, such as high-temperature drilling, reservoir characterisation, reservoir fracturing, microseismic monitoring and high-temperature power stations, originate from the field of oil and drilling. Addressing how to take advantage of these developed technologies is a key factor in the development of HDR reserves. Based on the thermal crustal structure in China, HDR resources can be divided into four types： high radioactive heat production, sedimentary basin, modern volcano and the inner-plate active tectonic belt. The prospective regions of HDR resources are located in South Tibet, West Yunnan, the southeast coast of China, Bohai Rim, Songliao Basin and Guanzhong Basin. The related essential technologies are relatively mature, and the prospect of HDR power generation is promising. Therefore, analysing the formation mechanisms of HDR resources and promoting the transformation of technological achievements, large-scale development and the utilisation of HDR resources can be achieved in China.
文摘This paper summarizes the distribution and production layout of the major mineral resources in China,including coal,iron ore,copper and bauxite,from a national perspective.It also identifies the incompatibility between the mineral resources distribution and regional economic development.Significant issues with China's mineral resource industry cause challenges for the sustainable development of both the mining industry and the national socio-economy.The sustainability of regional mineral resources and the environmental pollution by mining in the western China were also analyzed.Results show that the distribution of China's mineral resources is misaligned with its regional layout of economic development.China's mineral resources have been over-exploited,and the mineral resources production in the eastern China is unsustainable.The continuously expanding production of mineral resources in the western China has heavily endangered the ecological environment.We propose strategies to boost the sustainable development of mineral resources,including measures to accelerate economic development and enhance the sustainability of domestic mineral resources.We also offer suggestions for scientifically planning the mineral resource prospecting and exploitation and regional economic layout,as well as for proactively undertaking industry transfer in the eastern China and raising the environmental benchmark requirements for the mineral industry in the central and western China.
文摘Service and information resources are two kinds of major shared resources in virtual enterprises, where, service resources include third party’s service resources and enterprise’s legacy service resources,and information resources include database resources and file resources. Since service and information resources have distributed, autonomic, remotely bound as well as some other similar characteristics, an implementation mechanism on managing shared resources based on UDDI are presented. XML instances are used to describe resources authorization information, WSDL based special XML instance represents information resource metadata, and these XML instances are referenced by tModel for realizing the purpose of managing shared resources metadata based on UDDI.
基金Supported by the National Basic Research Program of China under Grant No 2013CB338002the National Natural Science Foundation of China under Grant Nos 11304397 and 61505261
文摘The quantum key distribution （QKD） allows two parties to share a secret key by typically making use of a one-way quantum channel. Howevery the two-way QKD has its own unique advantages, which means the two-way QKD has become a focus recently. To improve the practieM performance of the two-way QKD, we present a security analysis of a two-way QKD protocol based on the decoy method with heralded single-photon sources （HSPSs）. We make use of two approaches to calculate the yield and the quantum bit error rate of single-photon and two-photon pulses. Then we present the secret key generation rate based on the GLLP formula. The numerical simulation shows that the protocol with HSPSs has an advantage in the secure distance compared with weak coherent state sources. In addition, we present the final secret key by considering the statistical fluctuation of the yield generation rate of the LM05 protocol with finite resources and the error rate.
基金supported by Major Projects of Oil and Gas of China (No. 2011ZX05018-002)
文摘Unconventional hydrocarbon resources, which are only marginally economically explored and developed by traditional methods and techniques, are different from conventional hydrocarbon resources in their accumulation mechanisms, occurrence states, distribution models, and exploration and development manners. The types of unconventional hydrocarbon are controlled by the evolu- tion of the source rocks and the combinations of different types of unconventional reservoirs. The fundamental dis- tinction between unconventional hydrocarbon resources and conventional hydrocarbon resources is their non- buoyancy-driven migration. The development of the micro- to nano-scale pores results in rather high capillary resis- tance. The accumulation mechanisms of the unconven- tional and the conventional hydrocarbon resources are also greatly different. In conventional hydrocarbon resources, oil and gas entrapment is controlled by reservoir-forming factors and geological events, which is a dynamic balance process; while for unconventional hydrocarbon resources, the gas content is affected by the temperature and pressure fields, and their preservation is crucial. Unconventional and conventional hydrocarbons are distributed in an orderly manner in subsurface space, having three distribution models of intra-source rock, basin-centered, and source rock interlayer. These results will be of great significance to unconventional hydrocarbon exploration.
基金supported by the Shanghai Municipal Social Science Foundation(No.2020BGL032).
文摘Taking an industrial park as an example,this study aims to analyze the characteristics of a distribution network that incorporates distributed energy resources(DERs).The study begins by summarizing the key features of a distribution network with DERs based on recent power usage data.To predict and analyze the load growth of the industrial park,an improved back-propagation algorithm is employed.Furthermore,the study classifies users within the industrial park according to their specific power consumption and supply requirements.This user segmentation allows for the introduction of three constraints:node voltage,wire current,and capacity of DERs.By incorporating these constraints,the study constructs an optimization model for the distribution network in the industrial park,with the objective of minimizing the total operation and maintenance cost.The primary goal of these optimizations is to address the needs of DERs connected to the distribution network,while simultaneously mitigating their potential adverse impact on the network.Additionally,the study aims to enhance the overall energy efficiency of the industrial park through more efficient utilization of resources.
基金supported by the National Natural Science Foundation of China (grant No. 40773038the Program of High-level Geological Talents (201309)Youth Geological Talents (201112) of the China Geological Survey
文摘The metamorphosed sedimentary type of iron deposits（BIF） is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Carajas in Brazil, Hamersley in Australia, Kursk in Russia, Central Province of India and Anshan-Benxi in China. Subordinated types of iron deposits are magmatic, volcanic-hosted and sedimentary ones. This paper briefly introduces the geological characteristics of major super-large iron ore clusters in the world. The proven reserves of iron ores in China are relatively abundant, but they are mainly low-grade ores. Moreover, a considerate part of iron ores are difficult to utilize for their difficult ore dressing, deep burial or other reasons. Iron ore deposits are relatively concentrated in 11 metallogenic provinces（belts）, such as the Anshan-Benxi, eastern Hebei, Xichang-Central Yunnan Province and middle-lower reaches of Yangtze River. The main minerogenetic epoches vary widely from the Archean to Quaternary, and are mainly the Late Archean to Middle Proterozoic, Variscan, and Yanshanian periods. The main 7 genetic types of iron deposits in China are metamorphosed sedimentary type（BIF）, magmatic type, volcanic-hosted type, skarn type, hydrothermal type, sedimentary type and weathered leaching type. The iron-rich ores occur predominantly in the skarn and marine volcanic-hosted iron deposits, locally in the metamorphosed sedimentary type（BIF） as hydrothermal reformation products. The theory of minerogenetic series of mineral deposits and minerogenic models has applied in investigation and prospecting of iron ore deposits. A combination of deep analyses of aeromagnetic anomalies and geomagnetic anomalies, with gravity anomalies are an effective method to seeking large and deep-buried iron deposits. China has a relatively great oresearching potential of iron ores, especially for metamorphosed sedimentary, skarn, and marine volcanic-hosted iron deposits. For the lower guarantee degree of iron and steel industry, China should give a trading and open the foreign mining markets.
文摘This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.
基金The Science and Technology Development Fund,Macao SAR(File No.0011/2022/AGJFile No.SKL-IOTSC(UM)-2021-2023).
文摘The paradigm shift from a coal-based power system to a renewable-energy-based power system brings more challenges to the supply-demand balance of the grid.Distributed energy resources(DERs),which can provide operating reserve to the grid,are regarded as a promising solution to compensate for the power fluctuation of the renewable energy resources.Small-scale DERs can be aggregated as a virtual power plant(VPP),which is eligible to bid in the operating reserve market.Since the DERs usually belong to different entities,it is important to investigate the VPP operation framework that coordinates the DERs in a trusted man-ner.In this paper,we propose a blockchain-assisted operating reserve framework for VPPs that aggregates various DERs.Considering the heterogeneity of various DERs,we propose a unified reserve capacity evaluation method to facilitate the aggregation of DERs.By considering the mismatch between actual available reserve capacity and the estimated value,the performance of VPP in the operating reserve market is improved.A hardware-based experimental system is developed,and numerical results are presented to demonstrate the effectiveness of the proposed framework.
文摘The distribution of resources is the basis of safety management.Based on thesystematic analysis of a resource distribution system affecting the level of safety,the bestdistribution proportion between safety activities and production and best resources distributionproportion among the various links of security activities are presented.Moreover,itis stated that the distribution of resources law needs to be researched deeply in practicalwork to achieve optimization of safety management practice.
基金Sichuan Provincial Department of Science and Technology(2017SZYZF0004).
文摘In this study,the resource distribution,morphological characteristics,artificial cultivation and market circulation of Paris Polyphylla var.yunnanensis and its polygerm varieties in Yunnan were investigated by referring to the research literature,field investigation and our planting experience.It is found that P.polyphylla var.yunnanensis is widely distributed in Yunnan Province,realizing large-scale artificial cultivation,while the wild resources of polygerm varieties are almost on the verge of extinction and are in urgent need of protection.
基金supported by Research project on key technologies of exploration and development of middle and deep geothermal energy in Yunnan Province(202302AF080001).
文摘Geothermal resources have a very broad development prospect owing to their clean nature;accurate evaluation of their potential is an important basis for the realization of fine zoning and large-scale efficient development.Here,a geothermal evaluation system is established based on reservoir,cap-rock,transportation-system,heat-source,and water-source data.The entropy weight Technique Order Preference by Similarity to an Ideal Solution(TOPSIS)and Analytic Hierarchy Process-Technique Order Preference by Similarity to an Ideal Solution(AHPTOPSIS)methods are used to evaluate geothermal resources in Eryuan County,and the evaluation results are superimposed with equal weights,and combined with the Moran index,to determine the geothermal exploration potential.Our results show that geothermal resources in Eryuan County are abundant,being concentrated in Liantie Township,Qiaohou Town,junction of Sanying and Cibihu towns,and junction of Fengyu and Yousuo towns.The Moran index indicates that there is significant geothermal accumulation,with high geothermal values mainly distributed around the water system.Three types of geothermal models are established based on control factors.The first one is controlled by the combination of reservoir and cap rock,while the second one is controlled by heat source and the third one is controlled by the combination of reservoir and cap rock and heat source.The junctions of Sanying and Cibihu towns,and Fengyu and Yousuo towns,are evaluated to have high geothermal potential,and these may become the next favorable directions for geothermal exploration in Eryuan County.
文摘The accelerating global energy transition,driven by climate imperatives and technological advancements,demands fundamen-tal transformations in power systems.Smart grids,characterized by cyber-physical integration,distributed renewable resources,and data-driven intelligence,have emerged as the backbone of this evolution.This convergence,however,introduces unprecedented complexities in resilience,security,stability,and market operation.This special issue presents five pivotal studies addressing these interconnected challenges,offering novel methodologies and insights to advance the efficiency,resilience,and sustainability of modern power systems.
基金supported by the National Natural Science Foundation of China(62003167,62376029,62325304,U22B2046,62073079,62088101,62133003,61991403)the General Joint Fund of the Equipment Advance Research Program of Ministry of Education(8091B022114)the China Postdoctoral Science Foundation(2023M730255).
文摘Dear Editor,This letter deals with distributed resource allocation(DRA)over multiple interacting coalitions,where conflicts of interest may arise due to the relevance of one coalition’s decision to other coalitions’benefits.To address this challenge,a new model called intra-independent resource allocation game(IIRAG)is formulated under the framework of multi-coalition games.A new DRA algorithm is developed,which draws on techniques of variable replacement and leaderfollowing consensus.The proposed algorithm ensures linear convergence of the collective decision to the Nash equilibrium(NE)of the IIRAG,as well as satisfaction of the resource constraint throughout the iteration process.Numerical simulations validate the effectiveness of the proposed approach.
基金funded in part by Grant No.RG-15-135-43 from the Deanship of Scientific Research(DSR)at King Abdulaziz University in Saudi Arabia.
文摘The proliferation of distributed and renewable energy resources introduces additional operational challenges to power distribution systems.Transactive energy management,which allows networked neighborhood communities and houses to trade energy,is expected to be developed as an effective method for accommodating additional uncertainties and security mandates pertaining to distributed energy resources.This paper proposes and analyzes a two-layer transactive energy market in which houses in networked neighborhood community microgrids will trade energy in respective market layers.This paper studies the blockchain applications to satisfy socioeconomic and technological concerns of secure transactive energy management in a two-level power distribution system.The numerical results for practical networked microgrids located at IllinoisTech−Bronzeville in Chicago illustrate the validity of the proposed blockchain-based transactive energy management for devising a distributed,scalable,efficient,and cybersecured power grid operation.The conclusion of the paper summarizes the prospects for blockchain applications to transactive energy management in power distribution systems.
文摘Catering in scenic areas is an important part of tourist experiences,yet the existing research on catering resources mainly focuses on tourist satisfaction and resource development,with limited analysis on the impact of catering resources distribution on tourists’visiting willingness.Thus,based on case analysis,surveys and data analysis,this study selected Mount Tai Scenic Area as the research object to conduct an in-depth investigation on the impact of the distribution of catering resources on tourists’visiting willingness,which identified many challenges faced by the distribution of catering resources in the scenic area and their underlying causes,finding that while there were rich varieties and concentrated catering options in high-traffic areas with strong tourists’visiting willingness,significant gaps remained in locations with weak tourists’visiting willingness.Furthermore,the overall catering offerings in Mount Tai Scenic Area demonstrated a notable deficiency in food products that authentically integrate with Mount Tai’s distinctive cultural heritage.To address such issues,improvement strategies were proposed for the development of catering resources in Mount Tai Scenic Area,including spatial development and integration,exploration of cultural connotations,and enhancement of tourism value,which provided insights for refining management of catering resources in forest park scenic spot,optimizing catering services,and enhancing the tourism experience of tourists.
基金Supported by Guiyang Science and Technology Planning Project~~
文摘64 species （including 5 varieties）, 30 genera and 24 families of the edible ferns in Guizhou are preliminartiy confirmed, according to the combination of spot investigation and refereuce analySis：the species, genera and families account for 8.13%, 19.74% and 44.44% of ferns in Guizhou, respectively. The floristic composition characters and resource distribution of 23 kinds of the edible ferns in Guizhou are described.
基金The Natural Science Foundation of Jiangsu Province of China under contract No.BK20140438the Special Fund for the Fishery Resource Survey Project of East China Sea Region by the Ministry of Agriculture+1 种基金the Jiangsu Innovative Experiment Project for Postgraduate Students of China under contract No.CXZZ13_0275the Jiangsu Science and Technology Support Program of China under contract No.BE2012422
文摘Monthly fishery survey data of the small yellow croaker Larimichthys polyactis in the southern Yellow Sea from2003 and 2013 were employed to evaluate the variation in the resource distribution and biological characteristics（especially body length and sex ratio） in the population on a decadal scale.The results indicated that the small yellow croaker migrated from the Shawai fishing ground to the Dasha fishing ground in spring and was mainly distributed in the central and western parts of the Dasha fishing ground in April and May.Larimichthys polyactis in the Dasha fishing ground migrated eastward to offshore wintering grounds in autumn and reached the central Dasha fishing ground in October and November.The small yellow croaker entered the western waters of the Shawai fishing ground in winter.A large number of age 0＋ fish occurred in the Shawai and Jiangwai fishing grounds in October of 2003 and 2013.The body lengths of the spawning stock and wintering stock in 2013 were larger than those in 2003,and the monthly sex ratios（female to male） were significantly less than 1 in both years.The monthly distribution of this fish in the southern Yellow Sea was consistent with a previous finding that ＂the stock migrated between the wintering grounds in the west of Jeju Island and the Lüsi spawning grounds＂ but tended to move more northward,with the spawning grounds extending outward.In the past decade,body length variation experienced a decline after an increase,rather than a steady decrease.The sex ratio in the single-stick stow net showed a tendency to increase over the decade,but was either less than or more than 1 depending on the fishing gear;therefore,further studies should be conducted to determine the sex structure.
基金Supported by the Special Fund for Major Research Program of Guangxi Province(GKZ1298001-1-8)Medical Treatment and Public Health Research and Development Project of Guangxi Province(S201416-02)~~
文摘Brachystemma calycinum D. Don as an important rare medicinal plant, the market prospect is very promising. In this paper, the resource distribution, ecological environment, community structure, domestication of wild cultivar and market demand and status of Brachystemma calycinum were systematically studied, so as to provide a basis for resource development and utilization.
