Objectives:To measure the effect of social distancing on reducing daily deaths,infections and hospital resources needed for coronavirus disease 2019(COVID-19)patients during the first wave of the pandemic in Nordic co...Objectives:To measure the effect of social distancing on reducing daily deaths,infections and hospital resources needed for coronavirus disease 2019(COVID-19)patients during the first wave of the pandemic in Nordic countries.Methods:The observations of social distancing,daily deaths,infections along with the needed hospital resources for COVID-19 patient hospitalizations including the numbers of all hospital beds,beds needed in ICUs and infection wards,nursing staffs needed in ICUs and infection wards were collected from the Institute for Health Metrics and Evaluation(IHME)by the University of Washington.The observations of social distancing were based on the reduction in human contact relative to background levels for each location quantified by cell phone mobility data collected from IHME.The weighted data per 100,000 population gathered in a 40-day period of the first wave of the pandemic in Denmark,Finland,Iceland,Norway and Sweden.Statistical technique of panel data analysis is used to measure the associations between social distancing and COVID-19 indicators in long-run.Results:Results of dynamic long-run models confirm that a 1%rise in social distancing by reducing human contacts may decline daily deaths,daily infections,all hospital beds needed,beds/nurses needed in ICUs and beds/nurses needed in infection wards due COVID-19 pandemic by 1.13%,15.26%,1.10%,1.17%and 1.89%,respectively.Moreover,results of error correction models verify that if the equilibriums between these series are disrupted by a sudden change in social distancing,the lengths of restoring back to equilibrium are 67,62,40,22 and 49 days for daily deaths,daily infections,all hospital beds needed,nurses/beds needed in ICUs and nurses/beds needed in infection wards,respectively.Conclusion:Proper social distancing was a successful policy for tackling COVID-19 with falling mortality and infection rates as well as the needed hospital resources for patient hospitalizations in Nordic countries.The results alert governments of the need for continuously implementing social distancing policies while using vaccines to prevent national lockdowns and reduce the burden of patient hospitalizations.展开更多
The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extract...The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.展开更多
In October 2024,the Ministry of Natural Resources of PRC released the 2024 China Mineral Resources Report,which focuses on new progress since 2023 in the geological and mineral survey and evaluation,mineral resource e...In October 2024,the Ministry of Natural Resources of PRC released the 2024 China Mineral Resources Report,which focuses on new progress since 2023 in the geological and mineral survey and evaluation,mineral resource exploration and development,mine ecological restoration,green mine construction,new changes in mineral resource policies and regulations,new measures in mineral resource management,new situations in scientific and technological innovation,as well as the new achievements of the international geological and mineral cooperation.展开更多
Hidden champions play a critical role in China’s efforts to overcome technological and industrial“chokepoints”.These enterprises are pivotal for breaking free from Western technological embargoes,avoiding entrapmen...Hidden champions play a critical role in China’s efforts to overcome technological and industrial“chokepoints”.These enterprises are pivotal for breaking free from Western technological embargoes,avoiding entrapment in low-value-added production,and driving industrial upgrading.Given the distinct market environment in which China’s hidden champions have emerged,it is both timely and practically significant to examine their growth trajectories and underlying mechanisms.This study adopts a resource allocation perspective to investigate the development path of Chinese manufacturing enterprises into hidden champions,using a vertical case study of Hailiya Group.The findings reveal that such enterprises achieve hidden champion status by vertically concentrating on niche markets while harnessing technological potential and horizontally diversifying their technology application scenarios.Their growth follows a“T-shaped”strategy,combining vertical specialization in a focused market with horizontal expansion into new applications.Four critical mechanisms underpin the rise of manufacturing hidden champions:market niche positioning,innovation-driven focus,application scenario expansion,and ecosystem development.Specifically,these enterprises strategically target niche markets,establish a technology-oriented competitive edge,broaden technology applications to unlock new profit opportunities,and develop collaborative ecosystems to share resources and drive industrial advancement.This paper not only extends the interpretive boundaries of resource allocation theory but also offers fresh insights into the emergence of Chinese manufacturing enterprises as hidden champions,enriching our understanding of their unique growth dynamics.展开更多
Aiming at the problems of increasing uncertainty of low-carbon generation energy in active distribution network(ADN)and the difficulty of security assessment of distribution network,this paper proposes a two-phase sch...Aiming at the problems of increasing uncertainty of low-carbon generation energy in active distribution network(ADN)and the difficulty of security assessment of distribution network,this paper proposes a two-phase scheduling model for flexible resources in ADN based on probabilistic risk perception.First,a full-cycle probabilistic trend sequence is constructed based on the source-load historical data,and in the day-ahead scheduling phase,the response interval of the flexibility resources on the load and storage side is optimized based on the probabilistic trend,with the probability of the security boundary as the security constraint,and with the economy as the objective.Then in the intraday phase,the core security and economic operation boundary of theADNis screened in real time.Fromthere,it quantitatively senses the degree of threat to the core security and economic operation boundary under the current source-load prediction information,and identifies the strictly secure and low/high-risk time periods.Flexibility resources within the response interval are dynamically adjusted in real-time by focusing on high-risk periods to cope with future core risks of the distribution grid.Finally,the improved IEEE 33-node distribution system is simulated to obtain the flexibility resource scheduling scheme on the load and storage side.Thescheduling results are evaluated from the perspectives of risk probability and flexible resource utilization efficiency,and the analysis shows that the scheduling model in this paper can promote the consumption of low-carbon energy from wind and photovoltaic sourceswhile reducing the operational risk of the distribution network.展开更多
Accurate estimation of evapotranspiration(ET)is crucial for efficient water resource management,particularly in the face of climate change and increasing water scarcity.This study performs a bibliometric analysis of 3...Accurate estimation of evapotranspiration(ET)is crucial for efficient water resource management,particularly in the face of climate change and increasing water scarcity.This study performs a bibliometric analysis of 352 articles and a systematic review of 35 peer-reviewed papers,selected according to PRISMA guidelines,to evaluate the performance of Hybrid Artificial Neural Networks(HANNs)in ET estimation.The findings demonstrate that HANNs,particularly those combining Multilayer Perceptrons(MLPs),Recurrent Neural Networks(RNNs),and Convolutional Neural Networks(CNNs),are highly effective in capturing the complex nonlinear relationships and tem-poral dependencies characteristic of hydrological processes.These hybrid models,often integrated with optimization algorithms and fuzzy logic frameworks,significantly improve the predictive accuracy and generalization capabilities of ET estimation.The growing adoption of advanced evaluation metrics,such as Kling-Gupta Efficiency(KGE)and Taylor Diagrams,highlights the increasing demand for more robust performance assessments beyond traditional methods.Despite the promising results,challenges remain,particularly regarding model interpretability,computational efficiency,and data scarcity.Future research should prioritize the integration of interpretability techniques,such as attention mechanisms,Local Interpretable Model-Agnostic Explanations(LIME),and feature importance analysis,to enhance model transparency and foster stakeholder trust.Additionally,improving HANN models’scalability and computational efficiency is crucial,especially for large-scale,real-world applications.Approaches such as transfer learning,parallel processing,and hyperparameter optimization will be essential in overcoming these challenges.This study underscores the transformative potential of HANN models for precise ET estimation,particularly in water-scarce and climate-vulnerable regions.By integrating CNNs for automatic feature extraction and leveraging hybrid architectures,HANNs offer considerable advantages for optimizing water management,particularly agriculture.Addressing challenges related to interpretability and scalability will be vital to ensuring the widespread deployment and operational success of HANNs in global water resource management.展开更多
The accelerated population growth of the elderly(individuals aged 60 years or more)across the globe has many indications,including changes in demography,health,the psycho-social milieu,and economic security.This trans...The accelerated population growth of the elderly(individuals aged 60 years or more)across the globe has many indications,including changes in demography,health,the psycho-social milieu,and economic security.This transition has given rise to varied challenges;significant changes have been observed in regard to developing strategies for health care systems across the globe.The World Health Organization(WHO)is also engaging in initiatives and mediating processes.Furthermore,advocacy is being conducted regarding a shift toward the salutogenic model from the pathogenic model.The concept behind this move was to shift from disablement to enablement and from illness to wellness,with the notion of mental health promotion(MHP)being promoted.This article attempts to discuss the MHP of elderly individuals,with special reference to the need to disseminate knowledge and awareness in the community by utilizing the resources of the health sector available in the WHO South-East Asia Region countries.We have tried to present the current knowledge gap by exploring the existing infrastructure,human resources,and financial resources.There is much to do to promote the mental health of the elderly,but inadequate facilities are available.Based on available resources,a roadmap for MHP in elderly individuals is discussed.展开更多
Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fer...Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different ADG.Twelve calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host phenotype.Results During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this effect.Moreover,no significant differences were observed in rumen fermentation parameters and serum indices between the two groups.Conclusions The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves.展开更多
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a...Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC.展开更多
Background: In the near future in Japan, chronic dialysis patients will likely face a situation where the aging and the lengthening of hemodialysis treatment periods will adversely affect the mobility-related activiti...Background: In the near future in Japan, chronic dialysis patients will likely face a situation where the aging and the lengthening of hemodialysis treatment periods will adversely affect the mobility-related activities of daily living (MR-ADL). The aim of this study was to investigate chronological change in MR-ADL among chronic dialysis patients in need of long-term care and the effect of admission to long-term care facilities on their MR-ADL. Methods: Data were analyzed from a long-term care eligibility assessment survey conducted in late March 2009 of 1000 individuals residing in Niigata City, Japan who were approved to receive long-term care. Then data from those individuals who had undergone the assessment survey ≥4 times over a period of ≥4 years were statistically evaluated. To reveal change in MR-ADL, this study performed a three-way analysis of variance with mean survey scores from assessment categories 2 - 5 containing questions related to MR-ADL as the independent variable and the number of eligibility assessment surveys (within-subjects factor), facility admission, and dialysis therapy (between-subjects factors) as dependent variables. Results: We observed the effect of facility admission in individuals aged >70 years for categories 2 - 5, and observed the effect of the number of assessment surveys taken only in women ≥80 years for categories 2 and 5. Regarding the effect of dialysis therapy, female dialysis patients aged ≥80 years and in need of long-term care scored significantly higher on survey items for transferring, grooming, toileting, eating, and instrumental activities of daily living, all of which are indicators of a moderate decline in ADL. Conclusions: Because dialysis is often initiated in women aged around 80 years, ADL in this group of individuals can be improved by the initiation and proper provision of dialysis.展开更多
Collaborative edge computing is a promising direction to handle the computation intensive tasks in B5G wireless networks.However,edge computing servers(ECSs)from different operators may not trust each other,and thus t...Collaborative edge computing is a promising direction to handle the computation intensive tasks in B5G wireless networks.However,edge computing servers(ECSs)from different operators may not trust each other,and thus the incentives for collaboration cannot be guaranteed.In this paper,we propose a consortium blockchain enabled collaborative edge computing framework,where users can offload computing tasks to ECSs from different operators.To minimize the total delay of users,we formulate a joint task offloading and resource optimization problem,under the constraint of the computing capability of each ECS.We apply the Tammer decomposition method and heuristic optimization algorithms to obtain the optimal solution.Finally,we propose a reputation based node selection approach to facilitate the consensus process,and also consider a completion time based primary node selection to avoid monopolization of certain edge node and enhance the security of the blockchain.Simulation results validate the effectiveness of the proposed algorithm,and the total delay can be reduced by up to 40%compared with the non-cooperative case.展开更多
A combination of factors, including inadequate interactive influence of professional human resource needs, contributes to low adoption of forest innovations. This study was conducted to assess the influence of quantit...A combination of factors, including inadequate interactive influence of professional human resource needs, contributes to low adoption of forest innovations. This study was conducted to assess the influence of quantity of professional human resource needs on adoption of forest innovations across relevant institutions in Kenya. The study considered 51 main institutions involved in, or support conservation activities, of which 33 were public, 14 non-governmental, and 4 private. Purposive sampling was used due to the heterogeneity of the institutions involved in conservation. Primary data were collected using a structured questionnaire. A quartile graph-based quantitative model was used to establish the differences in capacity variation expressed as expected variation region or the common cause and the unexpected variation region or the special cause. The latter should be investigated and acted upon. Statistical analysis involved Levene’s Test of Equality of Variances. Embracing both approaches confirmed the model as an appropriate quantitative analytical framework for assessing and articulating elements of institutional capacity, and that quantity of professional human capital (P < 0.05) is key to influencing adoption of forest innovations in Kenya. The study reiterates that to overcome professional capacity gaps and respond to conservation paradigm shift, quantity was relevant and was an imperative policy issue.展开更多
In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in th...In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in the world market.In China,resource-based state-owned enterprises(SOEs)are tasked with the mission of safeguarding resource security,and their internationalization development ideas and strategic deployment are significantly and fundamentally different from those of other non-state-owned enterprises and large multinational corporations.This study provides ideas for the globalization policies of enterprises in developing countries.We consider J Group in western China as a case and discuss its productive investment and global production network development from 2010 to 2019.We found that J Group was‘Partly'globalized,and there are multiple core nodes with the characteristics of centralized and decentralized coexistence in the production network;in addition,the overall layout centre shifted to Southeast Asia and China;however,its global production was restricted by the enterprise's investment security considerations,support and restrictions of the home country,political security risk of the host country,and sanctions from the West.These findings provide insights for future research:under the wave of anti-globalization and'internal circulation as the main body',resource SOEs should consider the potential risk of investment,especially keeping the middle and downstream industrial chain in China as much as possible.展开更多
Federated Edge Learning(FEL),an emerging distributed Machine Learning(ML)paradigm,enables model training in a distributed environment while ensuring user privacy by using physical separation for each user’s data.Howe...Federated Edge Learning(FEL),an emerging distributed Machine Learning(ML)paradigm,enables model training in a distributed environment while ensuring user privacy by using physical separation for each user’s data.However,with the development of complex application scenarios such as the Internet of Things(IoT)and Smart Earth,the conventional resource allocation schemes can no longer effectively support these growing computational and communication demands.Therefore,joint resource optimization may be the key solution to the scaling problem.This paper simultaneously addresses the multifaceted challenges of computation and communication,with the growing multiple resource demands.We systematically review the joint allocation strategies for different resources(computation,data,communication,and network topology)in FEL,and summarize the advantages in improving system efficiency,reducing latency,enhancing resource utilization,and enhancing robustness.In addition,we present the potential ability of joint optimization to enhance privacy preservation by reducing communication requirements,indirectly.This work not only provides theoretical support for resource management in federated learning(FL)systems,but also provides ideas for potential optimal deployment in multiple real-world scenarios.By thoroughly discussing the current challenges and future research directions,it also provides some important insights into multi-resource optimization in complex application environments.展开更多
In the past 40 years of China's reform and opening up, China's economy has been developing rapidly, and industrialization and urbanization have begun to take shape. At present, China is heading towards an informatio...In the past 40 years of China's reform and opening up, China's economy has been developing rapidly, and industrialization and urbanization have begun to take shape. At present, China is heading towards an information society. Mineral resources have played a great supporting role during this process. During the whole of 2017, China consumed 2.344 billion tons of iron ore, 2.4 billion tons of cement and 3.65 billion tons of raw coal (Fig. 1).展开更多
Cloud Datacenter Network(CDN)providers usually have the option to scale their network structures to allow for far more resource capacities,though such scaling options may come with exponential costs that contradict th...Cloud Datacenter Network(CDN)providers usually have the option to scale their network structures to allow for far more resource capacities,though such scaling options may come with exponential costs that contradict their utility objectives.Yet,besides the cost of the physical assets and network resources,such scaling may also imposemore loads on the electricity power grids to feed the added nodes with the required energy to run and cool,which comes with extra costs too.Thus,those CDNproviders who utilize their resources better can certainly afford their services at lower price-units when compared to others who simply choose the scaling solutions.Resource utilization is a quite challenging process;indeed,clients of CDNs usually tend to exaggerate their true resource requirements when they lease their resources.Service providers are committed to their clients with Service Level Agreements(SLAs).Therefore,any amendment to the resource allocations needs to be approved by the clients first.In this work,we propose deploying a Stackelberg leadership framework to formulate a negotiation game between the cloud service providers and their client tenants.Through this,the providers seek to retrieve those leased unused resources from their clients.Cooperation is not expected from the clients,and they may ask high price units to return their extra resources to the provider’s premises.Hence,to motivate cooperation in such a non-cooperative game,as an extension to theVickery auctions,we developed an incentive-compatible pricingmodel for the returned resources.Moreover,we also proposed building a behavior belief function that shapes the way of negotiation and compensation for each client.Compared to other benchmark models,the assessment results showthat our proposed models provide for timely negotiation schemes,allowing for better resource utilization rates,higher utilities,and grid-friend CDNs.展开更多
The cloud platform has limited defense resources to fully protect the edge servers used to process crowd sensing data in Internet of Things.To guarantee the network's overall security,we present a network defense ...The cloud platform has limited defense resources to fully protect the edge servers used to process crowd sensing data in Internet of Things.To guarantee the network's overall security,we present a network defense resource allocation with multi-armed bandits to maximize the network's overall benefit.Firstly,we propose the method for dynamic setting of node defense resource thresholds to obtain the defender(attacker)benefit function of edge servers(nodes)and distribution.Secondly,we design a defense resource sharing mechanism for neighboring nodes to obtain the defense capability of nodes.Subsequently,we use the decomposability and Lipschitz conti-nuity of the defender's total expected utility to reduce the difference between the utility's discrete and continuous arms and analyze the difference theoretically.Finally,experimental results show that the method maximizes the defender's total expected utility and reduces the difference between the discrete and continuous arms of the utility.展开更多
文摘Objectives:To measure the effect of social distancing on reducing daily deaths,infections and hospital resources needed for coronavirus disease 2019(COVID-19)patients during the first wave of the pandemic in Nordic countries.Methods:The observations of social distancing,daily deaths,infections along with the needed hospital resources for COVID-19 patient hospitalizations including the numbers of all hospital beds,beds needed in ICUs and infection wards,nursing staffs needed in ICUs and infection wards were collected from the Institute for Health Metrics and Evaluation(IHME)by the University of Washington.The observations of social distancing were based on the reduction in human contact relative to background levels for each location quantified by cell phone mobility data collected from IHME.The weighted data per 100,000 population gathered in a 40-day period of the first wave of the pandemic in Denmark,Finland,Iceland,Norway and Sweden.Statistical technique of panel data analysis is used to measure the associations between social distancing and COVID-19 indicators in long-run.Results:Results of dynamic long-run models confirm that a 1%rise in social distancing by reducing human contacts may decline daily deaths,daily infections,all hospital beds needed,beds/nurses needed in ICUs and beds/nurses needed in infection wards due COVID-19 pandemic by 1.13%,15.26%,1.10%,1.17%and 1.89%,respectively.Moreover,results of error correction models verify that if the equilibriums between these series are disrupted by a sudden change in social distancing,the lengths of restoring back to equilibrium are 67,62,40,22 and 49 days for daily deaths,daily infections,all hospital beds needed,nurses/beds needed in ICUs and nurses/beds needed in infection wards,respectively.Conclusion:Proper social distancing was a successful policy for tackling COVID-19 with falling mortality and infection rates as well as the needed hospital resources for patient hospitalizations in Nordic countries.The results alert governments of the need for continuously implementing social distancing policies while using vaccines to prevent national lockdowns and reduce the burden of patient hospitalizations.
基金financially supported by the National Natural Science Foundation of China(Nos.52404328,52274412,and 52374418)the China Postdoctoral Science Foundation(No.2024M753248)。
文摘The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.
文摘In October 2024,the Ministry of Natural Resources of PRC released the 2024 China Mineral Resources Report,which focuses on new progress since 2023 in the geological and mineral survey and evaluation,mineral resource exploration and development,mine ecological restoration,green mine construction,new changes in mineral resource policies and regulations,new measures in mineral resource management,new situations in scientific and technological innovation,as well as the new achievements of the international geological and mineral cooperation.
基金supported by the following projects:The Youth Project of the National Natural Science Foundation of China(NSFC)“Research on Chinese Multinational Companies’Componovation under Resource Constraint:From a Dynamic Circulation Logic of Home and Host Countries”(Grant No.72102030)The Research Project of Humanities and Social Sciences of the Ministry of Education“Research on Chinese Multinational Companies’Learning by Doing Mechanism under Resource Constraint”(Grant No.21C10173022)The General Project of the China Postdoctoral Science Foundation“Research on the Realization Path and Motivations for the Domestic Replacement of Core Technologies for Chinese Manufacturing Enterprises”(Grant No.2022M720975).
文摘Hidden champions play a critical role in China’s efforts to overcome technological and industrial“chokepoints”.These enterprises are pivotal for breaking free from Western technological embargoes,avoiding entrapment in low-value-added production,and driving industrial upgrading.Given the distinct market environment in which China’s hidden champions have emerged,it is both timely and practically significant to examine their growth trajectories and underlying mechanisms.This study adopts a resource allocation perspective to investigate the development path of Chinese manufacturing enterprises into hidden champions,using a vertical case study of Hailiya Group.The findings reveal that such enterprises achieve hidden champion status by vertically concentrating on niche markets while harnessing technological potential and horizontally diversifying their technology application scenarios.Their growth follows a“T-shaped”strategy,combining vertical specialization in a focused market with horizontal expansion into new applications.Four critical mechanisms underpin the rise of manufacturing hidden champions:market niche positioning,innovation-driven focus,application scenario expansion,and ecosystem development.Specifically,these enterprises strategically target niche markets,establish a technology-oriented competitive edge,broaden technology applications to unlock new profit opportunities,and develop collaborative ecosystems to share resources and drive industrial advancement.This paper not only extends the interpretive boundaries of resource allocation theory but also offers fresh insights into the emergence of Chinese manufacturing enterprises as hidden champions,enriching our understanding of their unique growth dynamics.
基金supported by Key Technology Research and Application of Online Control Simulation and Intelligent Decision Making for Active Distribution Network(5108-202218280A-2-377-XG).
文摘Aiming at the problems of increasing uncertainty of low-carbon generation energy in active distribution network(ADN)and the difficulty of security assessment of distribution network,this paper proposes a two-phase scheduling model for flexible resources in ADN based on probabilistic risk perception.First,a full-cycle probabilistic trend sequence is constructed based on the source-load historical data,and in the day-ahead scheduling phase,the response interval of the flexibility resources on the load and storage side is optimized based on the probabilistic trend,with the probability of the security boundary as the security constraint,and with the economy as the objective.Then in the intraday phase,the core security and economic operation boundary of theADNis screened in real time.Fromthere,it quantitatively senses the degree of threat to the core security and economic operation boundary under the current source-load prediction information,and identifies the strictly secure and low/high-risk time periods.Flexibility resources within the response interval are dynamically adjusted in real-time by focusing on high-risk periods to cope with future core risks of the distribution grid.Finally,the improved IEEE 33-node distribution system is simulated to obtain the flexibility resource scheduling scheme on the load and storage side.Thescheduling results are evaluated from the perspectives of risk probability and flexible resource utilization efficiency,and the analysis shows that the scheduling model in this paper can promote the consumption of low-carbon energy from wind and photovoltaic sourceswhile reducing the operational risk of the distribution network.
文摘Accurate estimation of evapotranspiration(ET)is crucial for efficient water resource management,particularly in the face of climate change and increasing water scarcity.This study performs a bibliometric analysis of 352 articles and a systematic review of 35 peer-reviewed papers,selected according to PRISMA guidelines,to evaluate the performance of Hybrid Artificial Neural Networks(HANNs)in ET estimation.The findings demonstrate that HANNs,particularly those combining Multilayer Perceptrons(MLPs),Recurrent Neural Networks(RNNs),and Convolutional Neural Networks(CNNs),are highly effective in capturing the complex nonlinear relationships and tem-poral dependencies characteristic of hydrological processes.These hybrid models,often integrated with optimization algorithms and fuzzy logic frameworks,significantly improve the predictive accuracy and generalization capabilities of ET estimation.The growing adoption of advanced evaluation metrics,such as Kling-Gupta Efficiency(KGE)and Taylor Diagrams,highlights the increasing demand for more robust performance assessments beyond traditional methods.Despite the promising results,challenges remain,particularly regarding model interpretability,computational efficiency,and data scarcity.Future research should prioritize the integration of interpretability techniques,such as attention mechanisms,Local Interpretable Model-Agnostic Explanations(LIME),and feature importance analysis,to enhance model transparency and foster stakeholder trust.Additionally,improving HANN models’scalability and computational efficiency is crucial,especially for large-scale,real-world applications.Approaches such as transfer learning,parallel processing,and hyperparameter optimization will be essential in overcoming these challenges.This study underscores the transformative potential of HANN models for precise ET estimation,particularly in water-scarce and climate-vulnerable regions.By integrating CNNs for automatic feature extraction and leveraging hybrid architectures,HANNs offer considerable advantages for optimizing water management,particularly agriculture.Addressing challenges related to interpretability and scalability will be vital to ensuring the widespread deployment and operational success of HANNs in global water resource management.
文摘The accelerated population growth of the elderly(individuals aged 60 years or more)across the globe has many indications,including changes in demography,health,the psycho-social milieu,and economic security.This transition has given rise to varied challenges;significant changes have been observed in regard to developing strategies for health care systems across the globe.The World Health Organization(WHO)is also engaging in initiatives and mediating processes.Furthermore,advocacy is being conducted regarding a shift toward the salutogenic model from the pathogenic model.The concept behind this move was to shift from disablement to enablement and from illness to wellness,with the notion of mental health promotion(MHP)being promoted.This article attempts to discuss the MHP of elderly individuals,with special reference to the need to disseminate knowledge and awareness in the community by utilizing the resources of the health sector available in the WHO South-East Asia Region countries.We have tried to present the current knowledge gap by exploring the existing infrastructure,human resources,and financial resources.There is much to do to promote the mental health of the elderly,but inadequate facilities are available.Based on available resources,a roadmap for MHP in elderly individuals is discussed.
基金funded by National Key R&D Program of China(2022YFA1304204)Agricultural Science and Technology Innovation Program(CAAS-ASTIP-2017-FRI-04)Beijing Innovation Consortium of livestock Research System(BAIC05-2023)。
文摘Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different ADG.Twelve calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host phenotype.Results During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this effect.Moreover,no significant differences were observed in rumen fermentation parameters and serum indices between the two groups.Conclusions The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves.
基金the National Natural Science Foundation of China(No.52374279)the Natural Science Foundation of Shaanxi Province(No.2023-YBGY-055).
文摘Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC.
文摘Background: In the near future in Japan, chronic dialysis patients will likely face a situation where the aging and the lengthening of hemodialysis treatment periods will adversely affect the mobility-related activities of daily living (MR-ADL). The aim of this study was to investigate chronological change in MR-ADL among chronic dialysis patients in need of long-term care and the effect of admission to long-term care facilities on their MR-ADL. Methods: Data were analyzed from a long-term care eligibility assessment survey conducted in late March 2009 of 1000 individuals residing in Niigata City, Japan who were approved to receive long-term care. Then data from those individuals who had undergone the assessment survey ≥4 times over a period of ≥4 years were statistically evaluated. To reveal change in MR-ADL, this study performed a three-way analysis of variance with mean survey scores from assessment categories 2 - 5 containing questions related to MR-ADL as the independent variable and the number of eligibility assessment surveys (within-subjects factor), facility admission, and dialysis therapy (between-subjects factors) as dependent variables. Results: We observed the effect of facility admission in individuals aged >70 years for categories 2 - 5, and observed the effect of the number of assessment surveys taken only in women ≥80 years for categories 2 and 5. Regarding the effect of dialysis therapy, female dialysis patients aged ≥80 years and in need of long-term care scored significantly higher on survey items for transferring, grooming, toileting, eating, and instrumental activities of daily living, all of which are indicators of a moderate decline in ADL. Conclusions: Because dialysis is often initiated in women aged around 80 years, ADL in this group of individuals can be improved by the initiation and proper provision of dialysis.
基金supported in part by the National Key R&D Program of China under Grant 2020YFB1005900the National Natural Science Foundation of China under Grant 62001220+3 种基金the Jiangsu Provincial Key Research and Development Program under Grants BE2022068the Natural Science Foundation of Jiangsu Province under Grants BK20200440the Future Network Scientific Research Fund Project FNSRFP-2021-YB-03the Young Elite Scientist Sponsorship Program,China Association for Science and Technology.
文摘Collaborative edge computing is a promising direction to handle the computation intensive tasks in B5G wireless networks.However,edge computing servers(ECSs)from different operators may not trust each other,and thus the incentives for collaboration cannot be guaranteed.In this paper,we propose a consortium blockchain enabled collaborative edge computing framework,where users can offload computing tasks to ECSs from different operators.To minimize the total delay of users,we formulate a joint task offloading and resource optimization problem,under the constraint of the computing capability of each ECS.We apply the Tammer decomposition method and heuristic optimization algorithms to obtain the optimal solution.Finally,we propose a reputation based node selection approach to facilitate the consensus process,and also consider a completion time based primary node selection to avoid monopolization of certain edge node and enhance the security of the blockchain.Simulation results validate the effectiveness of the proposed algorithm,and the total delay can be reduced by up to 40%compared with the non-cooperative case.
文摘A combination of factors, including inadequate interactive influence of professional human resource needs, contributes to low adoption of forest innovations. This study was conducted to assess the influence of quantity of professional human resource needs on adoption of forest innovations across relevant institutions in Kenya. The study considered 51 main institutions involved in, or support conservation activities, of which 33 were public, 14 non-governmental, and 4 private. Purposive sampling was used due to the heterogeneity of the institutions involved in conservation. Primary data were collected using a structured questionnaire. A quartile graph-based quantitative model was used to establish the differences in capacity variation expressed as expected variation region or the common cause and the unexpected variation region or the special cause. The latter should be investigated and acted upon. Statistical analysis involved Levene’s Test of Equality of Variances. Embracing both approaches confirmed the model as an appropriate quantitative analytical framework for assessing and articulating elements of institutional capacity, and that quantity of professional human capital (P < 0.05) is key to influencing adoption of forest innovations in Kenya. The study reiterates that to overcome professional capacity gaps and respond to conservation paradigm shift, quantity was relevant and was an imperative policy issue.
基金supported by National Natural Science Foundation of China(Grants No.41971198 and 42371198)Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2023-it24).
文摘In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in the world market.In China,resource-based state-owned enterprises(SOEs)are tasked with the mission of safeguarding resource security,and their internationalization development ideas and strategic deployment are significantly and fundamentally different from those of other non-state-owned enterprises and large multinational corporations.This study provides ideas for the globalization policies of enterprises in developing countries.We consider J Group in western China as a case and discuss its productive investment and global production network development from 2010 to 2019.We found that J Group was‘Partly'globalized,and there are multiple core nodes with the characteristics of centralized and decentralized coexistence in the production network;in addition,the overall layout centre shifted to Southeast Asia and China;however,its global production was restricted by the enterprise's investment security considerations,support and restrictions of the home country,political security risk of the host country,and sanctions from the West.These findings provide insights for future research:under the wave of anti-globalization and'internal circulation as the main body',resource SOEs should consider the potential risk of investment,especially keeping the middle and downstream industrial chain in China as much as possible.
基金supported in part by the National Natural Science Foundation of China under Grant No.61701197in part by the National Key Research and Development Program of China under Grant No.2021YFA1000500(4)in part by the 111 Project under Grant No.B23008.
文摘Federated Edge Learning(FEL),an emerging distributed Machine Learning(ML)paradigm,enables model training in a distributed environment while ensuring user privacy by using physical separation for each user’s data.However,with the development of complex application scenarios such as the Internet of Things(IoT)and Smart Earth,the conventional resource allocation schemes can no longer effectively support these growing computational and communication demands.Therefore,joint resource optimization may be the key solution to the scaling problem.This paper simultaneously addresses the multifaceted challenges of computation and communication,with the growing multiple resource demands.We systematically review the joint allocation strategies for different resources(computation,data,communication,and network topology)in FEL,and summarize the advantages in improving system efficiency,reducing latency,enhancing resource utilization,and enhancing robustness.In addition,we present the potential ability of joint optimization to enhance privacy preservation by reducing communication requirements,indirectly.This work not only provides theoretical support for resource management in federated learning(FL)systems,but also provides ideas for potential optimal deployment in multiple real-world scenarios.By thoroughly discussing the current challenges and future research directions,it also provides some important insights into multi-resource optimization in complex application environments.
文摘In the past 40 years of China's reform and opening up, China's economy has been developing rapidly, and industrialization and urbanization have begun to take shape. At present, China is heading towards an information society. Mineral resources have played a great supporting role during this process. During the whole of 2017, China consumed 2.344 billion tons of iron ore, 2.4 billion tons of cement and 3.65 billion tons of raw coal (Fig. 1).
基金The Deanship of Scientific Research at Hashemite University partially funds this workDeanship of Scientific Research at the Northern Border University,Arar,KSA for funding this research work through the project number“NBU-FFR-2024-1580-08”.
文摘Cloud Datacenter Network(CDN)providers usually have the option to scale their network structures to allow for far more resource capacities,though such scaling options may come with exponential costs that contradict their utility objectives.Yet,besides the cost of the physical assets and network resources,such scaling may also imposemore loads on the electricity power grids to feed the added nodes with the required energy to run and cool,which comes with extra costs too.Thus,those CDNproviders who utilize their resources better can certainly afford their services at lower price-units when compared to others who simply choose the scaling solutions.Resource utilization is a quite challenging process;indeed,clients of CDNs usually tend to exaggerate their true resource requirements when they lease their resources.Service providers are committed to their clients with Service Level Agreements(SLAs).Therefore,any amendment to the resource allocations needs to be approved by the clients first.In this work,we propose deploying a Stackelberg leadership framework to formulate a negotiation game between the cloud service providers and their client tenants.Through this,the providers seek to retrieve those leased unused resources from their clients.Cooperation is not expected from the clients,and they may ask high price units to return their extra resources to the provider’s premises.Hence,to motivate cooperation in such a non-cooperative game,as an extension to theVickery auctions,we developed an incentive-compatible pricingmodel for the returned resources.Moreover,we also proposed building a behavior belief function that shapes the way of negotiation and compensation for each client.Compared to other benchmark models,the assessment results showthat our proposed models provide for timely negotiation schemes,allowing for better resource utilization rates,higher utilities,and grid-friend CDNs.
基金supported by the National Natural Science Foundation of China(NSFC)[grant numbers 62172377,61872205]the Shandong Provincial Natural Science Foundation[grant number ZR2019MF018]the Startup Research Foundation for Distinguished Scholars No.202112016.
文摘The cloud platform has limited defense resources to fully protect the edge servers used to process crowd sensing data in Internet of Things.To guarantee the network's overall security,we present a network defense resource allocation with multi-armed bandits to maximize the network's overall benefit.Firstly,we propose the method for dynamic setting of node defense resource thresholds to obtain the defender(attacker)benefit function of edge servers(nodes)and distribution.Secondly,we design a defense resource sharing mechanism for neighboring nodes to obtain the defense capability of nodes.Subsequently,we use the decomposability and Lipschitz conti-nuity of the defender's total expected utility to reduce the difference between the utility's discrete and continuous arms and analyze the difference theoretically.Finally,experimental results show that the method maximizes the defender's total expected utility and reduces the difference between the discrete and continuous arms of the utility.