Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon...Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies.展开更多
Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI ...Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI chip to solve these AI tasks efficiently and powerfully.Rapid progress has been made in the field of advanced chips recently,such as the development of photonic computing,the advancement of the quantum processors,the boost of the biomimetic chips,and so on.Designs tactics of the advanced chips can be conducted with elaborated consideration of materials,algorithms,models,architectures,and so on.Though a few reviews present the development of the chips from their unique aspects,reviews in the view of the latest design for advanced and AI chips are few.Here,the newest development is systematically reviewed in the field of advanced chips.First,background and mechanisms are summarized,and subsequently most important considerations for co-design of the software and hardware are illustrated.Next,strategies are summed up to obtain advanced and AI chips with high excellent performance by taking the important information processing steps into consideration,after which the design thought for the advanced chips in the future is proposed.Finally,some perspectives are put forward.展开更多
To ensure an uninterrupted power supply,mobile power sources(MPS)are widely deployed in power grids during emergencies.Comprising mobile emergency generators(MEGs)and mobile energy storage systems(MESS),MPS are capabl...To ensure an uninterrupted power supply,mobile power sources(MPS)are widely deployed in power grids during emergencies.Comprising mobile emergency generators(MEGs)and mobile energy storage systems(MESS),MPS are capable of supplying power to critical loads and serving as backup sources during grid contingencies,offering advantages such as flexibility and high resilience through electricity delivery via transportation networks.This paper proposes a design method for a 400 V–10 kV Dual-Winding Induction Generator(DWIG)intended for MEG applications,employing an improved particle swarmoptimization(PSO)algorithmbased on a back-propagation neural network(BPNN).A parameterized finite element(FE)model of the DWIG is established to derive constraints on its dimensional parameters,thereby simplifying the optimization space.Through sensitivity analysis between temperature rise and electromagnetic loss of the DWIG,the main factors influencing the machine’s temperature are identified,and electromagnetic loss is determined as the optimization objective.To obtain an accurate fitting function between electromagnetic loss and dimensional parameters,the BPNN is employed to predict the nonlinear relationship between the optimization objective and the parameters.The Latin hypercube sampling(LHS)method is used for random sampling in the FE model analysis for training,testing,and validation,which is then applied to compute the cost function in the PSO.Based on the relationships obtained by the BPNN,the PSO algorithm evaluates the fitness and cost functions to determine the optimal design point.The proposed optimization method is validated by comparing simulation results between the initial design and the optimized design.展开更多
Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety...Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety.The objective of this study is to design a subcritical reactor using a pressurized water reactor(PWR)conventional fuel following two safety points.In the first approach,deeply placed SCR cores with an infinite multiplication factor(k_(∞))of less than unity were identified using the DRAGON lattice code.In the second approach,subcritical reactor cores with an effective multiplication factor(k_(eff))of less than unity were determined by coupling the cell calculations of the DRAGON lattice code and core calculations of the DONJON code.For the deeply subcritical reactor design,it was found that the reactor would remain inherently subcritical while using fuel rods with ^(235)U enrichment of up to 0.9%,regardless of the pitch of the fuel rods.In the second approach,the optimal pitches(1.3 to 2.3 cm)were determined for different fuel enrichment values from 1 to 5%.Subsequently,the k_(eff) was obtained for a fuel rod arrangement of 8×8 to 80×80,and the states in which the reactor would be subcritical were determined for different fuel enrichments at the corresponding optimal pitch.To validate the models used in the DRAGON and DONJON codes,the k_(eff) of the Isfahan Light Water Subcritical Reactor(LWSCR)was experimentally measured and compared with the results of the calculations.Finally,the effects of fuel and moderator temperature changes were investigated to ensure that the designed assemblies remained in the subcritical state at all operational temperatures.展开更多
Building upon previous work （Lancaster, 2014） which defined and theoretically situated political monitoring as an analytical concept, this essay first reiterates the importance of political monitoring to the study o...Building upon previous work （Lancaster, 2014） which defined and theoretically situated political monitoring as an analytical concept, this essay first reiterates the importance of political monitoring to the study of institutions of governance and related policy design. The conceptualization of political monitoring builds upon the psychological notion that people change their behavior if they believe someone is watching them. Second, it discusses theoretically how and why policy design might incorporate political monitoring in order to produce specific outcomes. Third, it presents empirical evidence from several illustrative examples to demonstrate how the institutionalization of political monitoring affects policy outcomes.展开更多
In order to promote cleaner production in China, a package of policy options was presented based on the identification of the barriers encountered in the CP demonstration project and the effectiveness and feasibility ...In order to promote cleaner production in China, a package of policy options was presented based on the identification of the barriers encountered in the CP demonstration project and the effectiveness and feasibility of policy options for the CP implementation were analyzed. Furthermore, the policy mechanism framework was given, which composes of compulsory, economic incentive, social pressure and supportive function. Finally, the implementation strategy of the policy mechanism, in which the emphasis will be changed from compulsory policy options towards economic and social pressure policy options, was proposed.展开更多
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ...Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.展开更多
A necessary way to mitigate global warming is carbon reduction, which the international community is now actively promoting. China has committed a target goal for carbon reduction to the international society, and has...A necessary way to mitigate global warming is carbon reduction, which the international community is now actively promoting. China has committed a target goal for carbon reduction to the international society, and has devoted a great effort toward researching the impact of related policies. Carbon taxation and carbon trading are the two main mechanisms to advocate carbon abatement, which many countries have been using. Each of these two mechanisms possesses advantages and disadvantages, and an appropriate combination of them can make best use of their advantages while bypassing their disadvantages, creating a superior mechanism. In our opinion, the main differences between these two mechanisms are that carbon taxation has a lower institution cost(consisting of the related infrastructural investment and the regulation cost,etc), and is easier to operate, but lacks the flexibility in response to variations of market conditions. However, this flexibility is just the origin of risk, which increases the difficulty for firms in their decision of carbon abatement and is an indirect way to incentivize carbon abatement, compared to carbon trading, which has a more direct effect in carbon reduction. Based on the above observation, we present a hybrid mechanism of carbon abatement, which is an organized combination of carbon taxation and carbon trading. It consists of two parts: first, the carbon taxation, which has a progressive tax rate, second, the carbon trading. Small firms will only pay the carbon tax, while large firms, will first need to get the initial carbon emission quotas by some way, and then trade it in the carbon market if necessary. For firms with extra emissions,they will receive a punishment according to a high carbon tax rate. This hybrid policy considers the equity between different firms in carbon emission rights as well as the efficiency of the mechanism while decreasing the risk level for firms in the carbon emission decision, making it superior to the two previous policies. We also analyze the feasibility of this hybrid policy in China,address some important issues in the implementation of this hybrid policy in China and present the relevant suggestions. The discussion in this paper can serve as a reference to the government in the decision of carbon policies.展开更多
Gender-specific differences in the prevalence,incidence,comorbidities,prognosis,severity,risk factors,drug-related aspects and outcomes of various medical conditions are well documented.We present a literature review ...Gender-specific differences in the prevalence,incidence,comorbidities,prognosis,severity,risk factors,drug-related aspects and outcomes of various medical conditions are well documented.We present a literature review on the extent to which research in this field has developed over the years,and reveal gaps in gender-sensitive awareness between the clinical portrayal and the translation into gender-specific treatment regimens,guidelines and into gender-oriented preventive strategies and health policies.Subsequently,through the lens of gender,we describe these domains in detail for four selected medical conditions:Asthma,obesity and overweight,chronic kidney disease and coronavirus disease 2019.As some of the key gender differences become more apparent during adolescence,we focus on this developmental stage.Finally,we propose a model which is based on three influential issues:(1)Investigating gender-specific medical profiles of related health conditions,rather than a single disease;(2)The dynamics of gender disparities across developmental stages;and(3)An integrative approach which takes into account additional risk factors(ethnicity,socio-demographic variables,minorities,lifestyle habits etc.).Increasing the awareness of gender-specific medicine in daily practice and in tailored guidelines,already among adolescents,may reduce inequities,facilitate the prediction of future trends and properly address the characteristics and needs of certain subpopulations within each gender.展开更多
This study investigates the critical intersection of cyberpsychology and cybersecurity policy development in small and medium-sized enterprises (SMEs). Through a mixed-methods approach incorporating surveys of 523 emp...This study investigates the critical intersection of cyberpsychology and cybersecurity policy development in small and medium-sized enterprises (SMEs). Through a mixed-methods approach incorporating surveys of 523 employees across 78 SMEs, qualitative interviews, and case studies, the research examines how psychological factors influence cybersecurity behaviors and policy effectiveness. Key findings reveal significant correlations between psychological factors and security outcomes, including the relationship between self-efficacy and policy compliance (r = 0.42, p β = 0.37, p < 0.001). The study identifies critical challenges in risk perception, policy complexity, and organizational culture affecting SME cybersecurity implementation. Results demonstrate that successful cybersecurity initiatives require the integration of psychological principles with technical solutions. The research provides a framework for developing human-centric security policies that address both behavioral and technical aspects of cybersecurity in resource-constrained environments.展开更多
This article explores the design of a wireless fire alarm system supported by advanced data fusion technology.It includes discussions on the basic design ideas of the wireless fire alarm system,hardware design analysi...This article explores the design of a wireless fire alarm system supported by advanced data fusion technology.It includes discussions on the basic design ideas of the wireless fire alarm system,hardware design analysis,software design analysis,and simulation analysis,all supported by data fusion technology.Hopefully,this analysis can provide some reference for the rational application of data fusion technology to meet the actual design and application requirements of the system.展开更多
With the progress of urbanization,urban landscape design has garnered increasing attention.Urban landscape design can not only reflect the construction level of a city but also has the functions of beautifying the urb...With the progress of urbanization,urban landscape design has garnered increasing attention.Urban landscape design can not only reflect the construction level of a city but also has the functions of beautifying the urban environment and enhancing the city image.Modern art enriches the expression forms of urban landscape design,and its integration with urban landscape design can greatly improve the urban landscape.This article elaborated on the connotations of modern art and urban landscape design and analyzed the application of modern art in urban landscape design.The application of modern art can help to achieve the goal of urban landscape design to the maximum extent.展开更多
As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Ze...As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Zero Waste City pilot policy on PM_(2.5)concentration offers valuable insights into the policy’s effectiveness and provides a potential model for environmental governance worldwide.This study employs panel data from 293 Chinese cities from 2014 to 2022 to systematically analyze the impact of the Zero-Waste City policy on PM_(2.5)concentration using a difference-in-differences model.The findings indicate that the policy not only directly reduces PM_(2.5)concentration but also indirectly curbs PM_(2.5)emissions by enhancing green innovation and green economic efficiency.Moreover,the policy’s effects are found to be positively moderated by urban energy dependence and digital financial inclusion,while they are negatively moderated by the government debt ratio.Based on these findings,this study suggests that cities should actively develop their digital economy,reduce government debt,promote green innovation,and improve green economic efficiency,as doing so will enhance their implementation of environmental policies and promote sustainable urban development.展开更多
A high-temperature and high-pressure valve is the key equipment of a wind tunnel system;it controls the generation of high-temperature and high-pressure gas.To reduce the adverse impact of high-temperature and high-pr...A high-temperature and high-pressure valve is the key equipment of a wind tunnel system;it controls the generation of high-temperature and high-pressure gas.To reduce the adverse impact of high-temperature and high-pressure gas on the strength of the valve body,a cooling structure is set on the valve seat.This can significantly reduce the temperature of the valve body and valve seat.The effects of its structure on the cooling characteristics and stress of the valve seat are studied,and six main parameters that can completely describe the geometry of the cooling structure are proposed.The central composite design method is used to select sample points,and the multi-objective genetic algorithm(MOGA)method is used for optimal structural design.A modification method according to the main parameters for the valve seat is proposed.The results show that the cooling structure weakens the pressure-bearing capability of the valve seat.Among the six main parameters of the valve seat,the distance from the end face of the lower hole to the Z-axis and the distance from the axis of the lower hole to the origin of the coordinates have the most obvious effects on the average stress of the valve seat.An optimum design value is proposed.This work can provide a reference for the design of high-temperature and high-pressure valves.展开更多
基金Supported by the National Key Research and Development Program of China(2023YFB4104500,2023YFB4104502)the National Natural Science Foundation of China(22138013)the Taishan Scholar Project(ts201712020).
文摘Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies.
基金supported by the Hong Kong Polytechnic University(1-WZ1Y,1-W34U,4-YWER).
文摘Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI chip to solve these AI tasks efficiently and powerfully.Rapid progress has been made in the field of advanced chips recently,such as the development of photonic computing,the advancement of the quantum processors,the boost of the biomimetic chips,and so on.Designs tactics of the advanced chips can be conducted with elaborated consideration of materials,algorithms,models,architectures,and so on.Though a few reviews present the development of the chips from their unique aspects,reviews in the view of the latest design for advanced and AI chips are few.Here,the newest development is systematically reviewed in the field of advanced chips.First,background and mechanisms are summarized,and subsequently most important considerations for co-design of the software and hardware are illustrated.Next,strategies are summed up to obtain advanced and AI chips with high excellent performance by taking the important information processing steps into consideration,after which the design thought for the advanced chips in the future is proposed.Finally,some perspectives are put forward.
基金funded by the Science and Technology Projects of State Grid Corporation of China(Project No.J2024136).
文摘To ensure an uninterrupted power supply,mobile power sources(MPS)are widely deployed in power grids during emergencies.Comprising mobile emergency generators(MEGs)and mobile energy storage systems(MESS),MPS are capable of supplying power to critical loads and serving as backup sources during grid contingencies,offering advantages such as flexibility and high resilience through electricity delivery via transportation networks.This paper proposes a design method for a 400 V–10 kV Dual-Winding Induction Generator(DWIG)intended for MEG applications,employing an improved particle swarmoptimization(PSO)algorithmbased on a back-propagation neural network(BPNN).A parameterized finite element(FE)model of the DWIG is established to derive constraints on its dimensional parameters,thereby simplifying the optimization space.Through sensitivity analysis between temperature rise and electromagnetic loss of the DWIG,the main factors influencing the machine’s temperature are identified,and electromagnetic loss is determined as the optimization objective.To obtain an accurate fitting function between electromagnetic loss and dimensional parameters,the BPNN is employed to predict the nonlinear relationship between the optimization objective and the parameters.The Latin hypercube sampling(LHS)method is used for random sampling in the FE model analysis for training,testing,and validation,which is then applied to compute the cost function in the PSO.Based on the relationships obtained by the BPNN,the PSO algorithm evaluates the fitness and cost functions to determine the optimal design point.The proposed optimization method is validated by comparing simulation results between the initial design and the optimized design.
文摘Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety.The objective of this study is to design a subcritical reactor using a pressurized water reactor(PWR)conventional fuel following two safety points.In the first approach,deeply placed SCR cores with an infinite multiplication factor(k_(∞))of less than unity were identified using the DRAGON lattice code.In the second approach,subcritical reactor cores with an effective multiplication factor(k_(eff))of less than unity were determined by coupling the cell calculations of the DRAGON lattice code and core calculations of the DONJON code.For the deeply subcritical reactor design,it was found that the reactor would remain inherently subcritical while using fuel rods with ^(235)U enrichment of up to 0.9%,regardless of the pitch of the fuel rods.In the second approach,the optimal pitches(1.3 to 2.3 cm)were determined for different fuel enrichment values from 1 to 5%.Subsequently,the k_(eff) was obtained for a fuel rod arrangement of 8×8 to 80×80,and the states in which the reactor would be subcritical were determined for different fuel enrichments at the corresponding optimal pitch.To validate the models used in the DRAGON and DONJON codes,the k_(eff) of the Isfahan Light Water Subcritical Reactor(LWSCR)was experimentally measured and compared with the results of the calculations.Finally,the effects of fuel and moderator temperature changes were investigated to ensure that the designed assemblies remained in the subcritical state at all operational temperatures.
文摘Building upon previous work （Lancaster, 2014） which defined and theoretically situated political monitoring as an analytical concept, this essay first reiterates the importance of political monitoring to the study of institutions of governance and related policy design. The conceptualization of political monitoring builds upon the psychological notion that people change their behavior if they believe someone is watching them. Second, it discusses theoretically how and why policy design might incorporate political monitoring in order to produce specific outcomes. Third, it presents empirical evidence from several illustrative examples to demonstrate how the institutionalization of political monitoring affects policy outcomes.
文摘In order to promote cleaner production in China, a package of policy options was presented based on the identification of the barriers encountered in the CP demonstration project and the effectiveness and feasibility of policy options for the CP implementation were analyzed. Furthermore, the policy mechanism framework was given, which composes of compulsory, economic incentive, social pressure and supportive function. Finally, the implementation strategy of the policy mechanism, in which the emphasis will be changed from compulsory policy options towards economic and social pressure policy options, was proposed.
基金National Natural Science Foundation of China(U22A20191)。
文摘Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.
文摘A necessary way to mitigate global warming is carbon reduction, which the international community is now actively promoting. China has committed a target goal for carbon reduction to the international society, and has devoted a great effort toward researching the impact of related policies. Carbon taxation and carbon trading are the two main mechanisms to advocate carbon abatement, which many countries have been using. Each of these two mechanisms possesses advantages and disadvantages, and an appropriate combination of them can make best use of their advantages while bypassing their disadvantages, creating a superior mechanism. In our opinion, the main differences between these two mechanisms are that carbon taxation has a lower institution cost(consisting of the related infrastructural investment and the regulation cost,etc), and is easier to operate, but lacks the flexibility in response to variations of market conditions. However, this flexibility is just the origin of risk, which increases the difficulty for firms in their decision of carbon abatement and is an indirect way to incentivize carbon abatement, compared to carbon trading, which has a more direct effect in carbon reduction. Based on the above observation, we present a hybrid mechanism of carbon abatement, which is an organized combination of carbon taxation and carbon trading. It consists of two parts: first, the carbon taxation, which has a progressive tax rate, second, the carbon trading. Small firms will only pay the carbon tax, while large firms, will first need to get the initial carbon emission quotas by some way, and then trade it in the carbon market if necessary. For firms with extra emissions,they will receive a punishment according to a high carbon tax rate. This hybrid policy considers the equity between different firms in carbon emission rights as well as the efficiency of the mechanism while decreasing the risk level for firms in the carbon emission decision, making it superior to the two previous policies. We also analyze the feasibility of this hybrid policy in China,address some important issues in the implementation of this hybrid policy in China and present the relevant suggestions. The discussion in this paper can serve as a reference to the government in the decision of carbon policies.
文摘Gender-specific differences in the prevalence,incidence,comorbidities,prognosis,severity,risk factors,drug-related aspects and outcomes of various medical conditions are well documented.We present a literature review on the extent to which research in this field has developed over the years,and reveal gaps in gender-sensitive awareness between the clinical portrayal and the translation into gender-specific treatment regimens,guidelines and into gender-oriented preventive strategies and health policies.Subsequently,through the lens of gender,we describe these domains in detail for four selected medical conditions:Asthma,obesity and overweight,chronic kidney disease and coronavirus disease 2019.As some of the key gender differences become more apparent during adolescence,we focus on this developmental stage.Finally,we propose a model which is based on three influential issues:(1)Investigating gender-specific medical profiles of related health conditions,rather than a single disease;(2)The dynamics of gender disparities across developmental stages;and(3)An integrative approach which takes into account additional risk factors(ethnicity,socio-demographic variables,minorities,lifestyle habits etc.).Increasing the awareness of gender-specific medicine in daily practice and in tailored guidelines,already among adolescents,may reduce inequities,facilitate the prediction of future trends and properly address the characteristics and needs of certain subpopulations within each gender.
文摘This study investigates the critical intersection of cyberpsychology and cybersecurity policy development in small and medium-sized enterprises (SMEs). Through a mixed-methods approach incorporating surveys of 523 employees across 78 SMEs, qualitative interviews, and case studies, the research examines how psychological factors influence cybersecurity behaviors and policy effectiveness. Key findings reveal significant correlations between psychological factors and security outcomes, including the relationship between self-efficacy and policy compliance (r = 0.42, p β = 0.37, p < 0.001). The study identifies critical challenges in risk perception, policy complexity, and organizational culture affecting SME cybersecurity implementation. Results demonstrate that successful cybersecurity initiatives require the integration of psychological principles with technical solutions. The research provides a framework for developing human-centric security policies that address both behavioral and technical aspects of cybersecurity in resource-constrained environments.
基金Chongqing Engineering University Undergraduate Innovation and Entrepreneurship Training Program Project:Wireless Fire Automatic Alarm System(Project No.:CXCY2024017)Chongqing Municipal Education Commission Science and Technology Research Project:Development and Research of Chongqing Wireless Fire Automatic Alarm System(Project No.:KJQN202401906)。
文摘This article explores the design of a wireless fire alarm system supported by advanced data fusion technology.It includes discussions on the basic design ideas of the wireless fire alarm system,hardware design analysis,software design analysis,and simulation analysis,all supported by data fusion technology.Hopefully,this analysis can provide some reference for the rational application of data fusion technology to meet the actual design and application requirements of the system.
文摘With the progress of urbanization,urban landscape design has garnered increasing attention.Urban landscape design can not only reflect the construction level of a city but also has the functions of beautifying the urban environment and enhancing the city image.Modern art enriches the expression forms of urban landscape design,and its integration with urban landscape design can greatly improve the urban landscape.This article elaborated on the connotations of modern art and urban landscape design and analyzed the application of modern art in urban landscape design.The application of modern art can help to achieve the goal of urban landscape design to the maximum extent.
基金The authors declare that fund support was received from National Social Science Fund of China[Grant No.23BJL010].
文摘As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Zero Waste City pilot policy on PM_(2.5)concentration offers valuable insights into the policy’s effectiveness and provides a potential model for environmental governance worldwide.This study employs panel data from 293 Chinese cities from 2014 to 2022 to systematically analyze the impact of the Zero-Waste City policy on PM_(2.5)concentration using a difference-in-differences model.The findings indicate that the policy not only directly reduces PM_(2.5)concentration but also indirectly curbs PM_(2.5)emissions by enhancing green innovation and green economic efficiency.Moreover,the policy’s effects are found to be positively moderated by urban energy dependence and digital financial inclusion,while they are negatively moderated by the government debt ratio.Based on these findings,this study suggests that cities should actively develop their digital economy,reduce government debt,promote green innovation,and improve green economic efficiency,as doing so will enhance their implementation of environmental policies and promote sustainable urban development.
基金supported by the National Natural Science Foundation of China(No.52175067)the Zhejiang Key Research&Development Project(No.2021C01021)+1 种基金the Natural Science Foundation of Zhejiang Province(No.LY20E050016)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(CPSF)(No.GZC20241478)。
文摘A high-temperature and high-pressure valve is the key equipment of a wind tunnel system;it controls the generation of high-temperature and high-pressure gas.To reduce the adverse impact of high-temperature and high-pressure gas on the strength of the valve body,a cooling structure is set on the valve seat.This can significantly reduce the temperature of the valve body and valve seat.The effects of its structure on the cooling characteristics and stress of the valve seat are studied,and six main parameters that can completely describe the geometry of the cooling structure are proposed.The central composite design method is used to select sample points,and the multi-objective genetic algorithm(MOGA)method is used for optimal structural design.A modification method according to the main parameters for the valve seat is proposed.The results show that the cooling structure weakens the pressure-bearing capability of the valve seat.Among the six main parameters of the valve seat,the distance from the end face of the lower hole to the Z-axis and the distance from the axis of the lower hole to the origin of the coordinates have the most obvious effects on the average stress of the valve seat.An optimum design value is proposed.This work can provide a reference for the design of high-temperature and high-pressure valves.
