Farmland merging is a significant tool in comprehensive rural areas development. Although a broad range of research relating to this field already exists, not enough emphasis has yet been placed on this issue in Polan...Farmland merging is a significant tool in comprehensive rural areas development. Although a broad range of research relating to this field already exists, not enough emphasis has yet been placed on this issue in Poland. In all probability it would not be a point for broad discussion if this situation related to a country, where agriculture is negligible. Nonetheless, in Poland agriculture plays a very important role in the economy： it employs 17% of labour force and arable land covers about 60% of the total area. Yet, even where land consolidation work has been carried out for years, the expected effects are still not appreciable, mostly because of the disastrous formal and legal policy. This paper intends to make a contribution to the field of knowledge of farmland merging in Poland. Particular attention was focused on the importance of land management policy in the streamlining of land consolidation activities. The study brings a fresh view on the examination of the effectiveness of farmland merging work, based on two different formal procedures carried out in Poland. During the investigation the main obstacles and weaknesses in legal regulation were revealed while at the same time, producing possible solutions.展开更多
The long awaited cloud computing concept is a reality now due to the transformation of computer generations.However,security challenges have become the biggest obstacles for the advancement of this emerging technology...The long awaited cloud computing concept is a reality now due to the transformation of computer generations.However,security challenges have become the biggest obstacles for the advancement of this emerging technology.A well-established policy framework is defined in this paper to generate security policies which are compliant to requirements and capabilities.Moreover,a federated policy management schema is introduced based on the policy definition framework and a multi-level policy application to create and manage virtual clusters with identical or common security levels.The proposed model consists in the design of a well-established ontology according to security mechanisms,a procedure which classifies nodes with common policies into virtual clusters,a policy engine to enhance the process of mapping requests to a specific node as well as an associated cluster and matchmaker engine to eliminate inessential mapping processes.The suggested model has been evaluated according to performance and security parameters to prove the efficiency and reliability of this multilayered engine in cloud computing environments during policy definition,application and mapping procedures.展开更多
Established on June 26, 1986 by the consolidation of four former CAS subordinates (namely,the Office of Policy Research, Division of Management Science, Editorial Department of the Journal of Dialectics of Nature,... Established on June 26, 1986 by the consolidation of four former CAS subordinates (namely,the Office of Policy Research, Division of Management Science, Editorial Department of the Journal of Dialectics of Nature, and Section of Optimization and Overall Planning under the CAS Institute of Applied Mathematics), the Institute of Policy and Management (IPM), CAS, is characterized by interdisciplinary studies of social and natural sciences. It applies itself to theoretical, methodological and applied research into national strategies, policies and management for S&T development. It also provides consultancy services for government departments, local authorities and CAS on issues concerning S&T development, social and economic growth, S&T management and administration of enterprises.……展开更多
The economic valuation of water quality in a rapidly developing country such as China should be undertaken to determine when the benefits from rapid growth begin to exceed the costs from the same. The best approach is...The economic valuation of water quality in a rapidly developing country such as China should be undertaken to determine when the benefits from rapid growth begin to exceed the costs from the same. The best approach is to ascertain the total economic valuation of the environmental resource. This includes all of the various uses of the resource, and even those values that are unconnected to individual use (e.g. natural and aesthetic values). A method known as contingent valuation (CV) is used to ascertain these forms of value. This approach is demonstrated here in an application to river water quality in the Beijing area. A CV study is reported in which Beijing area citizens reported an average willingness to pay about 1.3% of annual income in order to prevent further deterioration of river water quality. Aggregation over the representative population indicates that the perceived cost of further river quality deterioration is in the neighbourhood of USD 60 million. Such a measure provides some indication of the socially desired “stopping point”—— in the pursuit of economic growth at the expense of environmental quality.展开更多
The policy and principles on management of radioactive wastes are stipulated.Cement solidification and bituminization unit has come into trial run. Solid radioactive waste is stored in tentative storage vault built...The policy and principles on management of radioactive wastes are stipulated.Cement solidification and bituminization unit has come into trial run. Solid radioactive waste is stored in tentative storage vault built in each of nuclear faCilities. Seventeen storages associated with applications of nuclear technology and radioisotopes have been built for provinces. Disposal of low and intermediate level radioactive wastes pursues the policy of 'regional disposal'. Four repositories have been planned to be built in northwest, southwest, south and east China respectively. A program for treatment and disposal of high level radioactive waste has been made.展开更多
The present study investigates an energy management strategy based on reinforcement learning for seriesparallel hybrid vehicles. Hybrid electric vehicles allow using more advanced power management policies because of ...The present study investigates an energy management strategy based on reinforcement learning for seriesparallel hybrid vehicles. Hybrid electric vehicles allow using more advanced power management policies because of their complexity of power management. Towards this feature, a Q-Learning algorithm is proposed to design an energy management strategy. Compared to previous studies, an online reward function is defined to optimize fuel consumption and battery life cycle. Moreover, in the provided method, prior knowledge of the cycle and exact modeling of the vehicle are not required. The introduced strategy is simulated for four driving cycles in MATLAB software linked with ADVISOR. The simulation results show that in the HWFET cycle, the fuel consumption decreases by 1.25 %, and battery life increases by 65% compared to the rule-based method implemented in ADVISOR. Also, the results for the other driving cycles confirm the self-improvement property. In addition, it has been depicted that in the case of change in the driving cycle, the method performance has been maintained and gained better performance than the rule-based controller.展开更多
Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash cont...Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash content. In addition, many environmental sensitive organic and mineral bound elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, Pb, and Mn etc. remain enriched in these coals. Such characteristics are associated with more severe environmental impacts due to mining and its utilization in coal based industries. Environmental challenges include large scale landscape damage, soil erosion, loss of forest ecosystem and wildlife habitat, air, water and soil pollution. Several physical and chemical methods are reported in literature for the removal of mineral matter, total sulfur and different forms of sulfur from high sulfur coal in northeast India. This paper may help different researchers and stakeholders to understand current state of research in the field. Initiatives may be taken towards sustainable use of coal resources by adopting innovative clean technologies and by implementing effective control measures and regulatory policies.展开更多
Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem h...Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem has often been ignored. The present study used the Xiangjiang River basin(XRB) as the study area, and the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST) model, demand quantification model,supply–demand ratio, and water flow formula were applied to explore the spatial heterogeneity, flow, and equilibrium between water supply and demand. The results demonstrated significant spatial heterogeneity in the upstream, midstream, and downstream regions.The areas of water shortage were mainly located the downstream of the Changsha–Zhuzhou–Xiangtan urban agglomeration, and the Hengyang basin was the most scarcity area. Affected by terrain gradients and human needs, water flow varied from-16.33 × 10^(8) m^(3) to 13.69 × 10^(8) m^(3)from the upstream to the downstream area, which provided a possibility to reduce spatial heterogeneity. In the future, measures such as strengthening water resource system control,sponge city construction, and dynamic monitoring technology should be taken to balance the supply and demand of water in different river sections of the basin. This study can provide references for regulating water resources allocation in different reaches of the basin.展开更多
In order to improve the energy efficiency of large-scale data centers, a virtual machine(VM) deployment algorithm called three-threshold energy saving algorithm(TESA), which is based on the linear relation between the...In order to improve the energy efficiency of large-scale data centers, a virtual machine(VM) deployment algorithm called three-threshold energy saving algorithm(TESA), which is based on the linear relation between the energy consumption and(processor) resource utilization, is proposed. In TESA, according to load, hosts in data centers are divided into four classes, that is,host with light load, host with proper load, host with middle load and host with heavy load. By defining TESA, VMs on lightly loaded host or VMs on heavily loaded host are migrated to another host with proper load; VMs on properly loaded host or VMs on middling loaded host are kept constant. Then, based on the TESA, five kinds of VM selection policies(minimization of migrations policy based on TESA(MIMT), maximization of migrations policy based on TESA(MAMT), highest potential growth policy based on TESA(HPGT), lowest potential growth policy based on TESA(LPGT) and random choice policy based on TESA(RCT)) are presented, and MIMT is chosen as the representative policy through experimental comparison. Finally, five research directions are put forward on future energy management. The results of simulation indicate that, as compared with single threshold(ST) algorithm and minimization of migrations(MM) algorithm, MIMT significantly improves the energy efficiency in data centers.展开更多
From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have s...From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have some problems unsolved since the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts made theoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flow with Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system included environmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservation and construction industry and renewable resource production incentive system that turn the direct administration and operation to management and services. The detail figure of the new model of cost-benefit flow is provided and the main points related are discussed in this paper.展开更多
In this paper, we explore network architecture anal key technologies for content-centric networking （CCN）, an emerging networking technology in the big-data era. We descrihe the structure anti operation mechanism of...In this paper, we explore network architecture anal key technologies for content-centric networking （CCN）, an emerging networking technology in the big-data era. We descrihe the structure anti operation mechanism of tl CCN node. Then we discuss mobility management, routing strategy, and caching policy in CCN. For better network performance, we propose a probability cache replacement policy that is based on cotent popularity. We also propose and evaluate a probability cache with evicted copy-up decision policy.展开更多
Ecological restoration measures implemented in China have profoundly impacted vegetation NPP.This study aimed to estimate the effects of the land conversion and management measures on the grassland ecosystem in semi-a...Ecological restoration measures implemented in China have profoundly impacted vegetation NPP.This study aimed to estimate the effects of the land conversion and management measures on the grassland ecosystem in semi-arid regions.Land use data were employed from 2000 to 2015 to compare land conversion and coverage changes in Xilingol grassland.Then,the contributions of land conversion and management policies were quantified by assessing the difference between actual NPP and climate-induced NPP changes.The results indicated that the grassland area had a net loss of 534.42 km^(2),and the net area of increased vegetation coverage was 74,683.05 km^(2).Furthermore,the total NPP increased by 8,010.73 Gg C·yr^(−1)(1 Gg=10^(9)g),of which the human activities,including grazing management measures(+6,809.40 Gg C·yr^(−1))and land conversion(45.72 Gg C·yr^(−1))contributed to 85.58%of the increase in NPP.Transformation from desert and farmland dominated grassland expansion and NPP increase,while urbanization and desertification caused large grassland reduction and NPP loss.The grazing management increased vegetation NPP in most regions except for some regions in the desert steppe and the farming-pastoral zone.Related policies should be further adjusted to strengthen the management of the desert steppe and farming-pastoral regions.展开更多
On 14 March 2019,Zimbabwe was hit by Cyclone Idai,leaving immeasurable destruction of unprecedented magnitude in its wake.In Chimanimani District,many lives were lost,many people were reported missing,and others were ...On 14 March 2019,Zimbabwe was hit by Cyclone Idai,leaving immeasurable destruction of unprecedented magnitude in its wake.In Chimanimani District,many lives were lost,many people were reported missing,and others were displaced.The question that immediately comes to mind is:Was the country prepared to manage the Cyclone Idai disaster?Reflecting on the community experiences,the purpose of this research was to interrogate the strength of the disaster risk reduction legislation and institutions in Zimbabwe in the face of meteorological hazards.The research also evaluated the extent of the impact Cyclone Idai had on the Chimanimani communities and the factors that increased the vulnerability to the cyclone.A mixed method approach that involved 1180 participants was used.The study found that disaster risk management legislation and institutions in Zimbabwe are weak.Cyclone Idai resulted in the loss of many human lives,loss of livelihoods,and massive damage to infrastructure.The cyclone exposed capacity and policy gaps in Zimbabwe’s disaster risk management system.The study makes a number of recommendations,including strengthening disaster legislation and policy,and disaster risk governance.Given the communities’response to the disaster occurrence,the study also recommends strengthening social capital.展开更多
1. Local ContentPolicy The approaches of combining the tax revenue preference of import tariff with the localization rate are performed first for the car products during the proceedings of accepting and using the adva...1. Local ContentPolicy The approaches of combining the tax revenue preference of import tariff with the localization rate are performed first for the car products during the proceedings of accepting and using the advanced technologies introduced from foreign countries and the proceeding of localization promoted by our展开更多
The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and ...The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders.展开更多
The Sundarban Mangrove Forest(SMF)is an intricate ecosystem containing the most varied and profuse natural resources of Bangladesh.This study presents empirical research,based on primary and secondary data,regarding t...The Sundarban Mangrove Forest(SMF)is an intricate ecosystem containing the most varied and profuse natural resources of Bangladesh.This study presents empirical research,based on primary and secondary data,regarding the social-ecological system(SES),social-ecological dynamics,different stakeholders and relevant management policies of small-scale or artisanal fisheries such as the SMF;showing how,despite extensive diversification,the livelihood activities of the artisanal fishers in the SMF all depend on the forest itself.Regardless of this critical importance of mangroves,however,deforestation continues due to immature death of mangroves,illegal logging,increased salinity,natural disasters and significant household consumption of mangrove wood by local people.As the mangroves are destroyed fish stocks,and other fishery resources are reduced,leading to moves of desperation among those whose livelihood has traditionally been fishing.The present study also considers several risks and shock factors in the fishers'livelihood:attacks by wild animals(especially tigers)and local bandits,illness,natural disasters,river bank erosion,and the cost of paying off corrupt officials.The artisanal fishers of the SMF have adopted different strategies for coping with these problems:developing partnerships,violating the fisheries management laws and regulations,migrating,placing greater responsibility on women,and bartering fishing knowledge and information.This study shows how the social component(human),the ecological component(mangrove resources)and the interphase aspects(local ecological knowledge,stakeholder's interest,and money lenders or middle man roles)of the SMF as an SES are linked in mutual interaction.It furthermore considers how the social-ecological dynamics of the SMF have negative impacts on artisanal fishermen's livelihoods.Hence there is an urgency to update existing policies and management issues for the sustainable utilization of the SMF resources,eventually contributing to the improvement of the artisanal fishers'livelihoods.展开更多
文摘Farmland merging is a significant tool in comprehensive rural areas development. Although a broad range of research relating to this field already exists, not enough emphasis has yet been placed on this issue in Poland. In all probability it would not be a point for broad discussion if this situation related to a country, where agriculture is negligible. Nonetheless, in Poland agriculture plays a very important role in the economy： it employs 17% of labour force and arable land covers about 60% of the total area. Yet, even where land consolidation work has been carried out for years, the expected effects are still not appreciable, mostly because of the disastrous formal and legal policy. This paper intends to make a contribution to the field of knowledge of farmland merging in Poland. Particular attention was focused on the importance of land management policy in the streamlining of land consolidation activities. The study brings a fresh view on the examination of the effectiveness of farmland merging work, based on two different formal procedures carried out in Poland. During the investigation the main obstacles and weaknesses in legal regulation were revealed while at the same time, producing possible solutions.
文摘The long awaited cloud computing concept is a reality now due to the transformation of computer generations.However,security challenges have become the biggest obstacles for the advancement of this emerging technology.A well-established policy framework is defined in this paper to generate security policies which are compliant to requirements and capabilities.Moreover,a federated policy management schema is introduced based on the policy definition framework and a multi-level policy application to create and manage virtual clusters with identical or common security levels.The proposed model consists in the design of a well-established ontology according to security mechanisms,a procedure which classifies nodes with common policies into virtual clusters,a policy engine to enhance the process of mapping requests to a specific node as well as an associated cluster and matchmaker engine to eliminate inessential mapping processes.The suggested model has been evaluated according to performance and security parameters to prove the efficiency and reliability of this multilayered engine in cloud computing environments during policy definition,application and mapping procedures.
文摘 Established on June 26, 1986 by the consolidation of four former CAS subordinates (namely,the Office of Policy Research, Division of Management Science, Editorial Department of the Journal of Dialectics of Nature, and Section of Optimization and Overall Planning under the CAS Institute of Applied Mathematics), the Institute of Policy and Management (IPM), CAS, is characterized by interdisciplinary studies of social and natural sciences. It applies itself to theoretical, methodological and applied research into national strategies, policies and management for S&T development. It also provides consultancy services for government departments, local authorities and CAS on issues concerning S&T development, social and economic growth, S&T management and administration of enterprises.……
文摘The economic valuation of water quality in a rapidly developing country such as China should be undertaken to determine when the benefits from rapid growth begin to exceed the costs from the same. The best approach is to ascertain the total economic valuation of the environmental resource. This includes all of the various uses of the resource, and even those values that are unconnected to individual use (e.g. natural and aesthetic values). A method known as contingent valuation (CV) is used to ascertain these forms of value. This approach is demonstrated here in an application to river water quality in the Beijing area. A CV study is reported in which Beijing area citizens reported an average willingness to pay about 1.3% of annual income in order to prevent further deterioration of river water quality. Aggregation over the representative population indicates that the perceived cost of further river quality deterioration is in the neighbourhood of USD 60 million. Such a measure provides some indication of the socially desired “stopping point”—— in the pursuit of economic growth at the expense of environmental quality.
文摘The policy and principles on management of radioactive wastes are stipulated.Cement solidification and bituminization unit has come into trial run. Solid radioactive waste is stored in tentative storage vault built in each of nuclear faCilities. Seventeen storages associated with applications of nuclear technology and radioisotopes have been built for provinces. Disposal of low and intermediate level radioactive wastes pursues the policy of 'regional disposal'. Four repositories have been planned to be built in northwest, southwest, south and east China respectively. A program for treatment and disposal of high level radioactive waste has been made.
文摘The present study investigates an energy management strategy based on reinforcement learning for seriesparallel hybrid vehicles. Hybrid electric vehicles allow using more advanced power management policies because of their complexity of power management. Towards this feature, a Q-Learning algorithm is proposed to design an energy management strategy. Compared to previous studies, an online reward function is defined to optimize fuel consumption and battery life cycle. Moreover, in the provided method, prior knowledge of the cycle and exact modeling of the vehicle are not required. The introduced strategy is simulated for four driving cycles in MATLAB software linked with ADVISOR. The simulation results show that in the HWFET cycle, the fuel consumption decreases by 1.25 %, and battery life increases by 65% compared to the rule-based method implemented in ADVISOR. Also, the results for the other driving cycles confirm the self-improvement property. In addition, it has been depicted that in the case of change in the driving cycle, the method performance has been maintained and gained better performance than the rule-based controller.
文摘Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash content. In addition, many environmental sensitive organic and mineral bound elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, Pb, and Mn etc. remain enriched in these coals. Such characteristics are associated with more severe environmental impacts due to mining and its utilization in coal based industries. Environmental challenges include large scale landscape damage, soil erosion, loss of forest ecosystem and wildlife habitat, air, water and soil pollution. Several physical and chemical methods are reported in literature for the removal of mineral matter, total sulfur and different forms of sulfur from high sulfur coal in northeast India. This paper may help different researchers and stakeholders to understand current state of research in the field. Initiatives may be taken towards sustainable use of coal resources by adopting innovative clean technologies and by implementing effective control measures and regulatory policies.
基金supported by National Natural Science Foundation of China(grant number 42171258,41877084)Natural Science Foundation of Hunan Province(grant number 2021JJ30448)。
文摘Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem has often been ignored. The present study used the Xiangjiang River basin(XRB) as the study area, and the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST) model, demand quantification model,supply–demand ratio, and water flow formula were applied to explore the spatial heterogeneity, flow, and equilibrium between water supply and demand. The results demonstrated significant spatial heterogeneity in the upstream, midstream, and downstream regions.The areas of water shortage were mainly located the downstream of the Changsha–Zhuzhou–Xiangtan urban agglomeration, and the Hengyang basin was the most scarcity area. Affected by terrain gradients and human needs, water flow varied from-16.33 × 10^(8) m^(3) to 13.69 × 10^(8) m^(3)from the upstream to the downstream area, which provided a possibility to reduce spatial heterogeneity. In the future, measures such as strengthening water resource system control,sponge city construction, and dynamic monitoring technology should be taken to balance the supply and demand of water in different river sections of the basin. This study can provide references for regulating water resources allocation in different reaches of the basin.
基金Project(61272148) supported by the National Natural Science Foundation of ChinaProject(20120162110061) supported by the Doctoral Programs of Ministry of Education of China+1 种基金Project(CX2014B066) supported by the Hunan Provincial Innovation Foundation for Postgraduate,ChinaProject(2014zzts044) supported by the Fundamental Research Funds for the Central Universities,China
文摘In order to improve the energy efficiency of large-scale data centers, a virtual machine(VM) deployment algorithm called three-threshold energy saving algorithm(TESA), which is based on the linear relation between the energy consumption and(processor) resource utilization, is proposed. In TESA, according to load, hosts in data centers are divided into four classes, that is,host with light load, host with proper load, host with middle load and host with heavy load. By defining TESA, VMs on lightly loaded host or VMs on heavily loaded host are migrated to another host with proper load; VMs on properly loaded host or VMs on middling loaded host are kept constant. Then, based on the TESA, five kinds of VM selection policies(minimization of migrations policy based on TESA(MIMT), maximization of migrations policy based on TESA(MAMT), highest potential growth policy based on TESA(HPGT), lowest potential growth policy based on TESA(LPGT) and random choice policy based on TESA(RCT)) are presented, and MIMT is chosen as the representative policy through experimental comparison. Finally, five research directions are put forward on future energy management. The results of simulation indicate that, as compared with single threshold(ST) algorithm and minimization of migrations(MM) algorithm, MIMT significantly improves the energy efficiency in data centers.
文摘From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have some problems unsolved since the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts made theoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flow with Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system included environmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservation and construction industry and renewable resource production incentive system that turn the direct administration and operation to management and services. The detail figure of the new model of cost-benefit flow is provided and the main points related are discussed in this paper.
基金supported by National Natural Science Foundation of China under Grant No.60872018 and No. 60902015Major National Science and Technology Project No. 2011ZX03005-004-03
文摘In this paper, we explore network architecture anal key technologies for content-centric networking （CCN）, an emerging networking technology in the big-data era. We descrihe the structure anti operation mechanism of tl CCN node. Then we discuss mobility management, routing strategy, and caching policy in CCN. For better network performance, we propose a probability cache replacement policy that is based on cotent popularity. We also propose and evaluate a probability cache with evicted copy-up decision policy.
基金This work was supported primarily by the State Key Research Development Program of China(No.2016YFC0501101),(No.2016YFC0503603).
文摘Ecological restoration measures implemented in China have profoundly impacted vegetation NPP.This study aimed to estimate the effects of the land conversion and management measures on the grassland ecosystem in semi-arid regions.Land use data were employed from 2000 to 2015 to compare land conversion and coverage changes in Xilingol grassland.Then,the contributions of land conversion and management policies were quantified by assessing the difference between actual NPP and climate-induced NPP changes.The results indicated that the grassland area had a net loss of 534.42 km^(2),and the net area of increased vegetation coverage was 74,683.05 km^(2).Furthermore,the total NPP increased by 8,010.73 Gg C·yr^(−1)(1 Gg=10^(9)g),of which the human activities,including grazing management measures(+6,809.40 Gg C·yr^(−1))and land conversion(45.72 Gg C·yr^(−1))contributed to 85.58%of the increase in NPP.Transformation from desert and farmland dominated grassland expansion and NPP increase,while urbanization and desertification caused large grassland reduction and NPP loss.The grazing management increased vegetation NPP in most regions except for some regions in the desert steppe and the farming-pastoral zone.Related policies should be further adjusted to strengthen the management of the desert steppe and farming-pastoral regions.
基金the Tsuro Trust for providing the funding for the research。
文摘On 14 March 2019,Zimbabwe was hit by Cyclone Idai,leaving immeasurable destruction of unprecedented magnitude in its wake.In Chimanimani District,many lives were lost,many people were reported missing,and others were displaced.The question that immediately comes to mind is:Was the country prepared to manage the Cyclone Idai disaster?Reflecting on the community experiences,the purpose of this research was to interrogate the strength of the disaster risk reduction legislation and institutions in Zimbabwe in the face of meteorological hazards.The research also evaluated the extent of the impact Cyclone Idai had on the Chimanimani communities and the factors that increased the vulnerability to the cyclone.A mixed method approach that involved 1180 participants was used.The study found that disaster risk management legislation and institutions in Zimbabwe are weak.Cyclone Idai resulted in the loss of many human lives,loss of livelihoods,and massive damage to infrastructure.The cyclone exposed capacity and policy gaps in Zimbabwe’s disaster risk management system.The study makes a number of recommendations,including strengthening disaster legislation and policy,and disaster risk governance.Given the communities’response to the disaster occurrence,the study also recommends strengthening social capital.
文摘1. Local ContentPolicy The approaches of combining the tax revenue preference of import tariff with the localization rate are performed first for the car products during the proceedings of accepting and using the advanced technologies introduced from foreign countries and the proceeding of localization promoted by our
基金supported by the National Natural Science Foundation of China(No.41271501)
文摘The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders.
基金We thank the fishers and other stakeholders who generously shared their time and knowledge.We are grateful to DAAD(Deutscher Akademisher Austausdienst),for financial support to conduct the research.We thank the anonymous reviewers and the editorial board for their helpful comments and suggestions on earlier versions of the manuscript.Special thanks to David Huisjen for helping with the English edition.
文摘The Sundarban Mangrove Forest(SMF)is an intricate ecosystem containing the most varied and profuse natural resources of Bangladesh.This study presents empirical research,based on primary and secondary data,regarding the social-ecological system(SES),social-ecological dynamics,different stakeholders and relevant management policies of small-scale or artisanal fisheries such as the SMF;showing how,despite extensive diversification,the livelihood activities of the artisanal fishers in the SMF all depend on the forest itself.Regardless of this critical importance of mangroves,however,deforestation continues due to immature death of mangroves,illegal logging,increased salinity,natural disasters and significant household consumption of mangrove wood by local people.As the mangroves are destroyed fish stocks,and other fishery resources are reduced,leading to moves of desperation among those whose livelihood has traditionally been fishing.The present study also considers several risks and shock factors in the fishers'livelihood:attacks by wild animals(especially tigers)and local bandits,illness,natural disasters,river bank erosion,and the cost of paying off corrupt officials.The artisanal fishers of the SMF have adopted different strategies for coping with these problems:developing partnerships,violating the fisheries management laws and regulations,migrating,placing greater responsibility on women,and bartering fishing knowledge and information.This study shows how the social component(human),the ecological component(mangrove resources)and the interphase aspects(local ecological knowledge,stakeholder's interest,and money lenders or middle man roles)of the SMF as an SES are linked in mutual interaction.It furthermore considers how the social-ecological dynamics of the SMF have negative impacts on artisanal fishermen's livelihoods.Hence there is an urgency to update existing policies and management issues for the sustainable utilization of the SMF resources,eventually contributing to the improvement of the artisanal fishers'livelihoods.
