Building a technology alliance is the main strategy for the United States to maintain its scientific and technological hegemony under its technopolitical strategic framework.After Joe Biden took office,the United Stat...Building a technology alliance is the main strategy for the United States to maintain its scientific and technological hegemony under its technopolitical strategic framework.After Joe Biden took office,the United States implemented“small yard with high fences”strategy for scientific and technological competition,as the first step toward building a technology alliance.The main goal is to restrict the flow of strategic emerging technologies and factors of innovation to rival countries.展开更多
Self-serving,rational agents sometimes cooperate to their mutual benefit.The two-player iterated prisoner′s dilemma game is a model for including the emergence of cooperation.It is generally believed that there is no...Self-serving,rational agents sometimes cooperate to their mutual benefit.The two-player iterated prisoner′s dilemma game is a model for including the emergence of cooperation.It is generally believed that there is no simple ultimatum strategy which a player can control the return of the other participants.The zero-determinant strategy in the iterated prisoner′s dilemma dramatically expands our understanding of the classic game by uncovering strategies that provide a unilateral advantage to sentient players pitted against unwitting opponents.However,strategies in the prisoner′s dilemma game are only two strategies.Are there these results for general multi-strategy games?To address this question,the paper develops a theory for zero-determinant strategies for multi-strategy games,with any number of strategies.The analytical results exhibit a similar yet different scenario to the case of two-strategy games.The results are also applied to the Snowdrift game,the Hawk-Dove game and the Chicken game.展开更多
The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition...The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search efficiency.First,two update strategies based on decomposition are used to update the evolving population and external archive,respectively.Second,a multiselection strategy is designed.The first strategy is for the subspace without a non-dominated solution.Among the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global search.The second strategy is for the subspace with a non-dominated solution.In the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local search.The third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated solutions.In the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to search.Third,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search efficiency.Finally,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test problems.The results show that the proposed algorithm has better performance.展开更多
Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longe...Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.展开更多
In reward-based crowdfunding, projects are to disclose the operational risks and mitigation strategies for delivering the physical rewards during the funding phase. However, limited knowledge exists regarding projects...In reward-based crowdfunding, projects are to disclose the operational risks and mitigation strategies for delivering the physical rewards during the funding phase. However, limited knowledge exists regarding projects’ operational risks and mitigation strategies during the funding phase. In contributing to the literature, the study uses data on Kickstarter.com and conducts a content analysis to explore themes and their relationships. The results reveal various operational risks and associated mitigation strategies. Among the identified themes, product-related, contract manufacturers, and supply markets are the most expected risks, while outsourced production and proactive sourcing are the popular mitigation strategies. Also, the finding reveals that proactive sourcing and outsourced production, in-house production and post-campaign sourcing, contract manufacturer risk, and project internal risk are themes forming clusters. The results extend crowdfunding risk disclosure literature and set the tone for future research in crowdfunding operational risk management. Finally, other business implications are drawn for crowdfunding practitioners.展开更多
In this paper,we study the optimal investment problem of an insurer whose surplus process follows the diffusion approximation of the classical Cramer-Lundberg model.Investment in the foreign markets is allowed,and the...In this paper,we study the optimal investment problem of an insurer whose surplus process follows the diffusion approximation of the classical Cramer-Lundberg model.Investment in the foreign markets is allowed,and therefore,the foreign exchange rate model is incorporated.Under the allowing of selling and borrowing,the problem of maximizing the expected exponential utility of terminal wealth is studied.By solving the corresponding Hamilton-Jacobi-Bellman equations,the optimal investment strategies and value functions are obtained.Finally,numerical analysis is presented.展开更多
Agriculture has become the backbone of most developing countries in the world, especially Tubah Sub-Division North West region, Cameroon. Following the COVID-19 pandemic and socio-political crisis that hit Cameroon’s...Agriculture has become the backbone of most developing countries in the world, especially Tubah Sub-Division North West region, Cameroon. Following the COVID-19 pandemic and socio-political crisis that hit Cameroon’s economy, there has been a steady increase in food insecurity, which has paved the way for farmers to adopt some sustainable strategies to boost agricultural productivity. Therefore, in trying to find models for survival and the pursuit of growth, farmers adopted some traditional farming methods and the use of local input as a means of sustainability. This study specifically seeks to analyze the effect of sustainability strategies on agricultural productivity in Tubah sub-division North West Region, Cameroon. The data was elicited via a survey questionnaire administered to 202 participating farmers selected from the different farmer organizations in the Tubah sub-division. Using cluster-sampling approach, proximity villages were grouped into four clusters of villages, and stratified sampling was used to select farmers to participate in the study. The objective of the study was achieved using OLS and quantile regression estimation techniques. The result showed evidence that the sustainability strategies implemented by the farmers decreased agricultural productivity in the 25th quantile, and at the 50th and 75th quantile, agricultural productivity still declined. This decline is because of unsustainable agricultural strategies like the use of slash and burn, the use of chemical fertilizers, inadequate capital, low level of education, inadequate farming experience, inadequate income, inadequate farm size, and the type of technology used for farming. Based on the findings, this study recommends that the government should organize training programs and seminars, subsidize farm inputs, grant agricultural loans to farmers, and initiate and support mechanized agriculture to boost agricultural productivity.展开更多
Background:The academic community is increasingly interested in understanding the mechanisms through which gratitude influences coping strategies.In addition,the role of gratitude in fostering long-term resilience and...Background:The academic community is increasingly interested in understanding the mechanisms through which gratitude influences coping strategies.In addition,the role of gratitude in fostering long-term resilience and mental health outcomes has garnered significant attention.This study explores the mechanisms through which gratitude affects problem-focused coping strategies and emotion-focused coping strategies by constructing models involving gratitude,perceived social support,self-esteem,and problem-focused coping strategies,as well as models involving gratitude,perceived social support,self-esteem,and emotion-focused coping strategies.Methods:A longitudinal survey was conducted on 1666 Chinese university students using highly reliable and valid scales,including the Gratitude Scale,Perceived Social Support Scale,Self-Esteem Scale,and Brief Coping Strategies Scale.To examine whether perceived social support and self-esteem play a significant indirect role in the relationship between gratitude and problem-focused coping strategies,as well as between gratitude and emotion-focused coping strategies.Differences in variables based on demographic variables:We used one-way ANOVA to test the differences in gratitude,perceived social support,self-esteem,problem-focused coping strategies,and emotion-focused coping strategies among students of different grades and ages.Additionally,independent samples t-tests were used to examine the differences between students of different genders and household registrations.Results:The study found that(1)Gratitude significantly positively predicted perceived social support(β=0.661,p<0.001),self-esteem(β=0.234,p<0.001),and problemfocused coping strategies(β=0.130,p<0.001);(2)Perceived social support significantly positively predicted self-esteem(β=0.440,p<0.001;β=0.439,p<0.001),problem-focused coping strategies(β=0.443,p<0.001),and emotion-focused coping strategies(β=0.279,p<0.001);(3)Self-esteem significantly positively predicted problem-focused coping strategies(β=0.172,p<0.001)and significantly negatively predicted emotion-focused coping strategies(β=−0.205,p<0.001);(4)Gratitude can influence problem-focused coping strategies through the dual indirect effect of two mediating variables.After the inclusion of the mediating variables,the effect of problem-focused coping strategies in the indirect model was further strengthened.(5)Gratitude can influence emotion-focused coping strategies through a completely indirect effect on perceived social support and self-esteem.After inserting the mediating variables,the effect of emotionfocused coping strategies in the mediating model is enhanced.Conclusion:Gratitude can directly and positively predict problem-focused coping strategies,and it can also positively predict problem-focused coping strategies through the dual indirect effect of two mediating variables.Gratitude does not significantly predict emotion-focused coping strategies directly,but it can influence emotion-focused coping strategies via a double indirect pathway.展开更多
This paper addresses the shortcomings of the Sparrow and Eagle Optimization Algorithm (SBOA) in terms of convergence accuracy, convergence speed, and susceptibility to local optima. To this end, an improved Sparrow an...This paper addresses the shortcomings of the Sparrow and Eagle Optimization Algorithm (SBOA) in terms of convergence accuracy, convergence speed, and susceptibility to local optima. To this end, an improved Sparrow and Eagle Optimization Algorithm (HS-SBOA) is proposed. Initially, the algorithm employs Iterative Mapping to generate an initial sparrow and eagle population, enhancing the diversity of the population during the global search phase. Subsequently, an adaptive weighting strategy is introduced during the exploration phase of the algorithm to achieve a balance between exploration and exploitation. Finally, to avoid the algorithm falling into local optima, a Cauchy mutation operation is applied to the current best individual. To validate the performance of the HS-SBOA algorithm, it was applied to the CEC2021 benchmark function set and three practical engineering problems, and compared with other optimization algorithms such as the Grey Wolf Optimization (GWO), Particle Swarm Optimization (PSO), and Whale Optimization Algorithm (WOA) to test the effectiveness of the improved algorithm. The simulation experimental results show that the HS-SBOA algorithm demonstrates significant advantages in terms of convergence speed and accuracy, thereby validating the effectiveness of its improved strategies.展开更多
Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural stab...Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural stability.However,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in SIBs.Thus,it is of significance to boost the sodium storage performance of NVP cathode material.Up to now,many methods have been developed to optimize the electrochemical performance of NVP cathode material.In this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology design.The foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so on.Furthermore,the challenges and prospects of high-performance NVP cathode material are also put forward.It is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.展开更多
Objectives:The statistics from World Health Organization show a high incidence of childhood maltreatment which has a negative impact on the development of middle school students;for this reason,it is necessary to inve...Objectives:The statistics from World Health Organization show a high incidence of childhood maltreatment which has a negative impact on the development of middle school students;for this reason,it is necessary to investigate the potential harms of childhood maltreatment.This study aimed to explore the direct negative consequences of childhood maltreatment on subjective well-being as well as the mediating roles of shyness and emotion regulation strategies.Methods:A random cluster sampling survey was conducted among 1021 Chinese middle school students(male 49.2%,female 50.8%).The Subjective Well-Being Scale(SWLS),The Positive affect and Negative affect scale(PANAS),and The Childhood Trauma were adopted Questionnaire-28 item Short Form(CTQ-SF),the Cheek and Buss Shyness Scale(RCBS),and the Emotion Regulation Questionnaire(ERQ)for data collection.SPSS PROCESS macros were used for data analysis.Results:The findings demonstrated that:(a)childhood maltreatment was negatively correlated with subjective well-being(r=−0.482,p<0.001);(b)shyness(β=−0.141,95%CI=[−0.190,−0.097])and the two emotion regulation strategies,namely cognitive reappraisal(β=−0.120,95%CI=[−0.167,−0.079])and expression suppression(β=−0.034,95%CI=[−0.063,−0.010]),partially mediated the association between childhood maltreatment and subjective well-being separately;(c)shyness and the two emotion regulation strategies partially mediated the relationship between childhood maltreatment and subjective well-being in a sequential pattern(β=−0.026,95%CI=[−0.041,−0.015];β=−0.022,95%CI=[−0.035,−0.012]).Conclusion:These findings provide new perspectives and strategies to understand and deal with children’s mental health problems.It shows that the intervention of shyness and emotion regulation strategies in adolescents is of great significance to improve individual subjective happiness.展开更多
University student Party branches serve as the Party’s grassroots organizations within universities and act as a bridge and link between the Party and students.Therefore,it is essential to strengthen the development ...University student Party branches serve as the Party’s grassroots organizations within universities and act as a bridge and link between the Party and students.Therefore,it is essential to strengthen the development of student Party branches and enhance the effectiveness of student Party member education and training.This paper summarizes and analyzes the issues in the construction of student Party branches in universities and explores strategies for improving their quality,aiming to provide a reference for relevant personnel.展开更多
Student engagement in learning is a concern for teachers in the implementation of blended learning,which reflects the effectiveness of the pedagogical measures taken by teachers.Blended learning encompasses traditiona...Student engagement in learning is a concern for teachers in the implementation of blended learning,which reflects the effectiveness of the pedagogical measures taken by teachers.Blended learning encompasses traditional blended,blended online,and blended synchronous,which combine synchronous and asynchronous teaching and learning activities.This paper adopts an inductive approach to investigate and analyse students‘engagement in learning from three dimensions:behavioural,affective and cognitive,specifically focusing on three meta-categories,namely,course structure and arrangement,choice of teaching and learning activities,and teacher’s role in relation to the course,to investigate the teaching of teachers of different disciplines in three vocational colleges and to analyse the pedagogical strategies that the teachers use in order to improve students’engagement in blended learning.The findings suggest that communicating about the course at the beginning of the semester,clarifying course requirements,and building a trusting relationship with students play a key role in increasing student engagement in blended learning,and that the use of digital tools is an important means of promoting students’behavioural and emotional active participation in learning.展开更多
This article focuses on the study of high school English teaching strategies from an interdisciplinary perspective.Through an in-depth analysis of the significance and implementation path of interdisciplinary teaching...This article focuses on the study of high school English teaching strategies from an interdisciplinary perspective.Through an in-depth analysis of the significance and implementation path of interdisciplinary teaching in high school English education,combined with practical teaching cases to explore how to effectively integrate knowledge from other disciplines with English teaching,this study aims to provide a useful reference for improving the quality of high school English teaching and cultivating students’comprehensive literacy.Interdisciplinary teaching can significantly stimulate students’interest in learning and improve their language proficiency and interdisciplinary thinking,laying a solid foundation for their future development.展开更多
Assessment is a crucial aspect of the teaching process for teachers.Teachers’assessment literacy is closely related to students’learning outcomes.The language assessment literacy of foreign language teachers is a si...Assessment is a crucial aspect of the teaching process for teachers.Teachers’assessment literacy is closely related to students’learning outcomes.The language assessment literacy of foreign language teachers is a significant component of both teachers’professional development and students’learning,and it has become a research hotspot in the field of domestic language testing.Based on clarifying the theoretical framework of language assessment literacy,this paper proposes the main cultivation paths for pre-service English teachers’language assessment literacy,aiming to provide inspiration and references for the cultivation,reform,and development of teachers in basic foreign language education.展开更多
To safeguard the ocean ecosystem,fuel cells are excellent candidates as the primary energy supply for marine vessels due to their high efficiency,low noise,and cleanliness.However,fuel cells in hybrid power systems ar...To safeguard the ocean ecosystem,fuel cells are excellent candidates as the primary energy supply for marine vessels due to their high efficiency,low noise,and cleanliness.However,fuel cells in hybrid power systems are highly susceptible to load transients,which can severely damage fuel cells and shorten their lifespan.Therefore,the formulation of energy management strategies accounting for power degradation is crucial and urgent.In this study,an improved strategy for equivalent consumption minimization strategy(ECMS)considering power degradation is proposed.The improved energy control strategy effectively controls the energy distribution of hydrogen fuel cells,lithium batteries,and supercapacitors in hybrid power ships.The proposed control strategy combines the ECMS with an adaptive filteringmethod.The main objective of the ECMS is to allocate power to the fuel cell systems and energy storage systems(ESS)to stabilize the power output of fuel cells,prolong their service life,and reduce the hydrogen consumption in fuel cells.The adaptive filteringmethod,by low-pass filtering of the energy in the energy storage system,is used to allocate power between lithium batteries and supercapacitors to minimize the effect of transient and peak energy output on the lifespan of lithium batteries.To verify the superiority of the control strategy,a mathematical model for the hybrid power system is developed.In comparison to traditional ECMS and traditional ECMS considering degradation,the improved ECMS considering power degradation shows better performance in the overall economy,the durability of fuel cells and batteries,and system dynamic performance.展开更多
This paper employs the SWOT-QSPM(Strength,Weakness,Opportunity,Threat-Quantitative Strategic Planning Matrix)analytical framework to conduct a strategic study on the preschool teacher education program,taking the pres...This paper employs the SWOT-QSPM(Strength,Weakness,Opportunity,Threat-Quantitative Strategic Planning Matrix)analytical framework to conduct a strategic study on the preschool teacher education program,taking the preschool teacher major of Zengcheng Vocational and Technical School in Guangzhou City as an example.Through in-depth interviews and qualitative and quantitative analysis methods,the current external opportunities and threats,internal strengths,and weaknesses faced by the major are assessed.Alternative strategies are proposed,and then the QSPM method is used to quantitatively evaluate these alternative strategies.It is concluded that a differentiation strategy should be adopted as the competitive strategy for the preschool teacher education program.The research findings have significant reference value for the development and planning of similar preschool teacher majors in higher vocational colleges.The practical significance lies in the fact that the research conclusions can be directly applied by education providers.The innovative significance lies in providing career planning references for current preschool teacher major students and their parents through strategic analysis.展开更多
Nature education program is an essential teaching content in kindergarten,which is not only conducive to enhancing children’s knowledge of the natural environment and awareness of protection but also cultivating thei...Nature education program is an essential teaching content in kindergarten,which is not only conducive to enhancing children’s knowledge of the natural environment and awareness of protection but also cultivating their exploratory ability.As the future practitioners of kindergarten education,preschool education majors in colleges and universities are now actively exploring the implementation strategies of kindergarten nature education programs and innovating the construction method of nature education programs,which not only directly affects the high quality of their future teaching work,but also helps to promote the cognitive development of young children and the enhancement of their practical skills.Based on this,this paper outlines the teaching strategies of a kindergarten nature education program from the perspective of letting young children get close to nature,discovering nature,and other aspects of preschool education majors in colleges and universities.展开更多
Infrared optoelectronic sensing is the core of many critical applications such as night vision,health and medication,military,space exploration,etc.Further including mechanical flexibility as a new dimension enables n...Infrared optoelectronic sensing is the core of many critical applications such as night vision,health and medication,military,space exploration,etc.Further including mechanical flexibility as a new dimension enables novel features of adaptability and conformability,promising for developing next-generation optoelectronic sensory applications toward reduced size,weight,price,power consumption,and enhanced performance(SWaP^(3)).However,in this emerging research frontier,challenges persist in simultaneously achieving high infrared response and good mechanical deformability in devices and integrated systems.Therefore,we perform a comprehensive review of the design strategies and insights of flexible infrared optoelectronic sensors,including the fundamentals of infrared photodetectors,selection of materials and device architectures,fabrication techniques and design strategies,and the discussion of architectural and functional integration towards applications in wearable optoelectronics and advanced image sensing.Finally,this article offers insights into future directions to practically realize the ultra-high performance and smart sensors enabled by infrared-sensitive materials,covering challenges in materials development and device micro-/nanofabrication.Benchmarks for scaling these techniques across fabrication,performance,and integration are presented,alongside perspectives on potential applications in medication and health,biomimetic vision,and neuromorphic sensory systems,etc.展开更多
Background:Childhood environmental unpredictability(CEU)is crucial to personal development,profoundly influence physical and psychological growth particularly,and psychopathy is recognized as a dark personality trait....Background:Childhood environmental unpredictability(CEU)is crucial to personal development,profoundly influence physical and psychological growth particularly,and psychopathy is recognized as a dark personality trait.The aim of this study is to investigate the effects of insecure attachment and life history strategy(LHS)on the relationship between CEU and psychopathy by establishing a sequential mediation model based on evolutionary life history theory and cognitive-affective personality system.Methods:A group of 532 undergraduates completed the measurements for CEU,insecure attachment,LHS,and psychopathy,and Bootstrap mediation test through SPSS 25.0 and PROCESS macro tool was used to examine the relationship among these variables.Results:The results revealed positive relations between CEU and insecure attachment(β=0.87,p<0.001),CEU and LHS(β=0.11,p<0.001),and CEU and psychopathy(β=0.14,p<0.001).Insecure attachment was also positively associated with LHS(β=0.62,p<0.001)and psychopathy(β=0.04,p<0.001).In addition,LHS was significantly associated with psychopathy(β=0.08,p<0.001).The relationship between CEU and psychopathy is mediated independently and sequentially by insecure attachment and LHS.Conclusion:The current research shows the relationship between CEU and psychopathy,as well as the mechanism of insecure attachment and life history strategy as mediators.展开更多
文摘Building a technology alliance is the main strategy for the United States to maintain its scientific and technological hegemony under its technopolitical strategic framework.After Joe Biden took office,the United States implemented“small yard with high fences”strategy for scientific and technological competition,as the first step toward building a technology alliance.The main goal is to restrict the flow of strategic emerging technologies and factors of innovation to rival countries.
文摘Self-serving,rational agents sometimes cooperate to their mutual benefit.The two-player iterated prisoner′s dilemma game is a model for including the emergence of cooperation.It is generally believed that there is no simple ultimatum strategy which a player can control the return of the other participants.The zero-determinant strategy in the iterated prisoner′s dilemma dramatically expands our understanding of the classic game by uncovering strategies that provide a unilateral advantage to sentient players pitted against unwitting opponents.However,strategies in the prisoner′s dilemma game are only two strategies.Are there these results for general multi-strategy games?To address this question,the paper develops a theory for zero-determinant strategies for multi-strategy games,with any number of strategies.The analytical results exhibit a similar yet different scenario to the case of two-strategy games.The results are also applied to the Snowdrift game,the Hawk-Dove game and the Chicken game.
基金supported by National Natural Science Foundations of China(nos.12271326,62102304,61806120,61502290,61672334,61673251)China Postdoctoral Science Foundation(no.2015M582606)+2 种基金Industrial Research Project of Science and Technology in Shaanxi Province(nos.2015GY016,2017JQ6063)Fundamental Research Fund for the Central Universities(no.GK202003071)Natural Science Basic Research Plan in Shaanxi Province of China(no.2022JM-354).
文摘The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search efficiency.First,two update strategies based on decomposition are used to update the evolving population and external archive,respectively.Second,a multiselection strategy is designed.The first strategy is for the subspace without a non-dominated solution.Among the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global search.The second strategy is for the subspace with a non-dominated solution.In the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local search.The third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated solutions.In the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to search.Third,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search efficiency.Finally,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test problems.The results show that the proposed algorithm has better performance.
基金supported by a Horizontal Project on the Development of a Hybrid Energy Storage Simulation Model for Wind Power Based on an RT-LAB Simulation System(PH2023000190)the Inner Mongolia Natural Science Foundation Project and the Optimization of Exergy Efficiency of a Hybrid Energy Storage System with Crossover Control for Wind Power(2023JQ04).
文摘Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.
文摘In reward-based crowdfunding, projects are to disclose the operational risks and mitigation strategies for delivering the physical rewards during the funding phase. However, limited knowledge exists regarding projects’ operational risks and mitigation strategies during the funding phase. In contributing to the literature, the study uses data on Kickstarter.com and conducts a content analysis to explore themes and their relationships. The results reveal various operational risks and associated mitigation strategies. Among the identified themes, product-related, contract manufacturers, and supply markets are the most expected risks, while outsourced production and proactive sourcing are the popular mitigation strategies. Also, the finding reveals that proactive sourcing and outsourced production, in-house production and post-campaign sourcing, contract manufacturer risk, and project internal risk are themes forming clusters. The results extend crowdfunding risk disclosure literature and set the tone for future research in crowdfunding operational risk management. Finally, other business implications are drawn for crowdfunding practitioners.
基金supported by the National Natural Science Foundation of China(Grant No.12301603).
文摘In this paper,we study the optimal investment problem of an insurer whose surplus process follows the diffusion approximation of the classical Cramer-Lundberg model.Investment in the foreign markets is allowed,and therefore,the foreign exchange rate model is incorporated.Under the allowing of selling and borrowing,the problem of maximizing the expected exponential utility of terminal wealth is studied.By solving the corresponding Hamilton-Jacobi-Bellman equations,the optimal investment strategies and value functions are obtained.Finally,numerical analysis is presented.
文摘Agriculture has become the backbone of most developing countries in the world, especially Tubah Sub-Division North West region, Cameroon. Following the COVID-19 pandemic and socio-political crisis that hit Cameroon’s economy, there has been a steady increase in food insecurity, which has paved the way for farmers to adopt some sustainable strategies to boost agricultural productivity. Therefore, in trying to find models for survival and the pursuit of growth, farmers adopted some traditional farming methods and the use of local input as a means of sustainability. This study specifically seeks to analyze the effect of sustainability strategies on agricultural productivity in Tubah sub-division North West Region, Cameroon. The data was elicited via a survey questionnaire administered to 202 participating farmers selected from the different farmer organizations in the Tubah sub-division. Using cluster-sampling approach, proximity villages were grouped into four clusters of villages, and stratified sampling was used to select farmers to participate in the study. The objective of the study was achieved using OLS and quantile regression estimation techniques. The result showed evidence that the sustainability strategies implemented by the farmers decreased agricultural productivity in the 25th quantile, and at the 50th and 75th quantile, agricultural productivity still declined. This decline is because of unsustainable agricultural strategies like the use of slash and burn, the use of chemical fertilizers, inadequate capital, low level of education, inadequate farming experience, inadequate income, inadequate farm size, and the type of technology used for farming. Based on the findings, this study recommends that the government should organize training programs and seminars, subsidize farm inputs, grant agricultural loans to farmers, and initiate and support mechanized agriculture to boost agricultural productivity.
基金Tourism College of Zhejiang Fund provided financial support for this research(Project Number:2023CGYB05).
文摘Background:The academic community is increasingly interested in understanding the mechanisms through which gratitude influences coping strategies.In addition,the role of gratitude in fostering long-term resilience and mental health outcomes has garnered significant attention.This study explores the mechanisms through which gratitude affects problem-focused coping strategies and emotion-focused coping strategies by constructing models involving gratitude,perceived social support,self-esteem,and problem-focused coping strategies,as well as models involving gratitude,perceived social support,self-esteem,and emotion-focused coping strategies.Methods:A longitudinal survey was conducted on 1666 Chinese university students using highly reliable and valid scales,including the Gratitude Scale,Perceived Social Support Scale,Self-Esteem Scale,and Brief Coping Strategies Scale.To examine whether perceived social support and self-esteem play a significant indirect role in the relationship between gratitude and problem-focused coping strategies,as well as between gratitude and emotion-focused coping strategies.Differences in variables based on demographic variables:We used one-way ANOVA to test the differences in gratitude,perceived social support,self-esteem,problem-focused coping strategies,and emotion-focused coping strategies among students of different grades and ages.Additionally,independent samples t-tests were used to examine the differences between students of different genders and household registrations.Results:The study found that(1)Gratitude significantly positively predicted perceived social support(β=0.661,p<0.001),self-esteem(β=0.234,p<0.001),and problemfocused coping strategies(β=0.130,p<0.001);(2)Perceived social support significantly positively predicted self-esteem(β=0.440,p<0.001;β=0.439,p<0.001),problem-focused coping strategies(β=0.443,p<0.001),and emotion-focused coping strategies(β=0.279,p<0.001);(3)Self-esteem significantly positively predicted problem-focused coping strategies(β=0.172,p<0.001)and significantly negatively predicted emotion-focused coping strategies(β=−0.205,p<0.001);(4)Gratitude can influence problem-focused coping strategies through the dual indirect effect of two mediating variables.After the inclusion of the mediating variables,the effect of problem-focused coping strategies in the indirect model was further strengthened.(5)Gratitude can influence emotion-focused coping strategies through a completely indirect effect on perceived social support and self-esteem.After inserting the mediating variables,the effect of emotionfocused coping strategies in the mediating model is enhanced.Conclusion:Gratitude can directly and positively predict problem-focused coping strategies,and it can also positively predict problem-focused coping strategies through the dual indirect effect of two mediating variables.Gratitude does not significantly predict emotion-focused coping strategies directly,but it can influence emotion-focused coping strategies via a double indirect pathway.
文摘This paper addresses the shortcomings of the Sparrow and Eagle Optimization Algorithm (SBOA) in terms of convergence accuracy, convergence speed, and susceptibility to local optima. To this end, an improved Sparrow and Eagle Optimization Algorithm (HS-SBOA) is proposed. Initially, the algorithm employs Iterative Mapping to generate an initial sparrow and eagle population, enhancing the diversity of the population during the global search phase. Subsequently, an adaptive weighting strategy is introduced during the exploration phase of the algorithm to achieve a balance between exploration and exploitation. Finally, to avoid the algorithm falling into local optima, a Cauchy mutation operation is applied to the current best individual. To validate the performance of the HS-SBOA algorithm, it was applied to the CEC2021 benchmark function set and three practical engineering problems, and compared with other optimization algorithms such as the Grey Wolf Optimization (GWO), Particle Swarm Optimization (PSO), and Whale Optimization Algorithm (WOA) to test the effectiveness of the improved algorithm. The simulation experimental results show that the HS-SBOA algorithm demonstrates significant advantages in terms of convergence speed and accuracy, thereby validating the effectiveness of its improved strategies.
基金partly supported by the National Natural Science Foundation of China(Grant No.52272225).
文摘Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural stability.However,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in SIBs.Thus,it is of significance to boost the sodium storage performance of NVP cathode material.Up to now,many methods have been developed to optimize the electrochemical performance of NVP cathode material.In this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology design.The foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so on.Furthermore,the challenges and prospects of high-performance NVP cathode material are also put forward.It is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.
基金Funded by the scientific research project of Hunan Department of Education(23A0098).
文摘Objectives:The statistics from World Health Organization show a high incidence of childhood maltreatment which has a negative impact on the development of middle school students;for this reason,it is necessary to investigate the potential harms of childhood maltreatment.This study aimed to explore the direct negative consequences of childhood maltreatment on subjective well-being as well as the mediating roles of shyness and emotion regulation strategies.Methods:A random cluster sampling survey was conducted among 1021 Chinese middle school students(male 49.2%,female 50.8%).The Subjective Well-Being Scale(SWLS),The Positive affect and Negative affect scale(PANAS),and The Childhood Trauma were adopted Questionnaire-28 item Short Form(CTQ-SF),the Cheek and Buss Shyness Scale(RCBS),and the Emotion Regulation Questionnaire(ERQ)for data collection.SPSS PROCESS macros were used for data analysis.Results:The findings demonstrated that:(a)childhood maltreatment was negatively correlated with subjective well-being(r=−0.482,p<0.001);(b)shyness(β=−0.141,95%CI=[−0.190,−0.097])and the two emotion regulation strategies,namely cognitive reappraisal(β=−0.120,95%CI=[−0.167,−0.079])and expression suppression(β=−0.034,95%CI=[−0.063,−0.010]),partially mediated the association between childhood maltreatment and subjective well-being separately;(c)shyness and the two emotion regulation strategies partially mediated the relationship between childhood maltreatment and subjective well-being in a sequential pattern(β=−0.026,95%CI=[−0.041,−0.015];β=−0.022,95%CI=[−0.035,−0.012]).Conclusion:These findings provide new perspectives and strategies to understand and deal with children’s mental health problems.It shows that the intervention of shyness and emotion regulation strategies in adolescents is of great significance to improve individual subjective happiness.
文摘University student Party branches serve as the Party’s grassroots organizations within universities and act as a bridge and link between the Party and students.Therefore,it is essential to strengthen the development of student Party branches and enhance the effectiveness of student Party member education and training.This paper summarizes and analyzes the issues in the construction of student Party branches in universities and explores strategies for improving their quality,aiming to provide a reference for relevant personnel.
文摘Student engagement in learning is a concern for teachers in the implementation of blended learning,which reflects the effectiveness of the pedagogical measures taken by teachers.Blended learning encompasses traditional blended,blended online,and blended synchronous,which combine synchronous and asynchronous teaching and learning activities.This paper adopts an inductive approach to investigate and analyse students‘engagement in learning from three dimensions:behavioural,affective and cognitive,specifically focusing on three meta-categories,namely,course structure and arrangement,choice of teaching and learning activities,and teacher’s role in relation to the course,to investigate the teaching of teachers of different disciplines in three vocational colleges and to analyse the pedagogical strategies that the teachers use in order to improve students’engagement in blended learning.The findings suggest that communicating about the course at the beginning of the semester,clarifying course requirements,and building a trusting relationship with students play a key role in increasing student engagement in blended learning,and that the use of digital tools is an important means of promoting students’behavioural and emotional active participation in learning.
文摘This article focuses on the study of high school English teaching strategies from an interdisciplinary perspective.Through an in-depth analysis of the significance and implementation path of interdisciplinary teaching in high school English education,combined with practical teaching cases to explore how to effectively integrate knowledge from other disciplines with English teaching,this study aims to provide a useful reference for improving the quality of high school English teaching and cultivating students’comprehensive literacy.Interdisciplinary teaching can significantly stimulate students’interest in learning and improve their language proficiency and interdisciplinary thinking,laying a solid foundation for their future development.
基金2021 Young Teacher Research Funding Project of Hubei Normal University(HS2021QN014)。
文摘Assessment is a crucial aspect of the teaching process for teachers.Teachers’assessment literacy is closely related to students’learning outcomes.The language assessment literacy of foreign language teachers is a significant component of both teachers’professional development and students’learning,and it has become a research hotspot in the field of domestic language testing.Based on clarifying the theoretical framework of language assessment literacy,this paper proposes the main cultivation paths for pre-service English teachers’language assessment literacy,aiming to provide inspiration and references for the cultivation,reform,and development of teachers in basic foreign language education.
基金The study was founded by the National Key R&D Program of China(2022YFB4301403).
文摘To safeguard the ocean ecosystem,fuel cells are excellent candidates as the primary energy supply for marine vessels due to their high efficiency,low noise,and cleanliness.However,fuel cells in hybrid power systems are highly susceptible to load transients,which can severely damage fuel cells and shorten their lifespan.Therefore,the formulation of energy management strategies accounting for power degradation is crucial and urgent.In this study,an improved strategy for equivalent consumption minimization strategy(ECMS)considering power degradation is proposed.The improved energy control strategy effectively controls the energy distribution of hydrogen fuel cells,lithium batteries,and supercapacitors in hybrid power ships.The proposed control strategy combines the ECMS with an adaptive filteringmethod.The main objective of the ECMS is to allocate power to the fuel cell systems and energy storage systems(ESS)to stabilize the power output of fuel cells,prolong their service life,and reduce the hydrogen consumption in fuel cells.The adaptive filteringmethod,by low-pass filtering of the energy in the energy storage system,is used to allocate power between lithium batteries and supercapacitors to minimize the effect of transient and peak energy output on the lifespan of lithium batteries.To verify the superiority of the control strategy,a mathematical model for the hybrid power system is developed.In comparison to traditional ECMS and traditional ECMS considering degradation,the improved ECMS considering power degradation shows better performance in the overall economy,the durability of fuel cells and batteries,and system dynamic performance.
文摘This paper employs the SWOT-QSPM(Strength,Weakness,Opportunity,Threat-Quantitative Strategic Planning Matrix)analytical framework to conduct a strategic study on the preschool teacher education program,taking the preschool teacher major of Zengcheng Vocational and Technical School in Guangzhou City as an example.Through in-depth interviews and qualitative and quantitative analysis methods,the current external opportunities and threats,internal strengths,and weaknesses faced by the major are assessed.Alternative strategies are proposed,and then the QSPM method is used to quantitatively evaluate these alternative strategies.It is concluded that a differentiation strategy should be adopted as the competitive strategy for the preschool teacher education program.The research findings have significant reference value for the development and planning of similar preschool teacher majors in higher vocational colleges.The practical significance lies in the fact that the research conclusions can be directly applied by education providers.The innovative significance lies in providing career planning references for current preschool teacher major students and their parents through strategic analysis.
文摘Nature education program is an essential teaching content in kindergarten,which is not only conducive to enhancing children’s knowledge of the natural environment and awareness of protection but also cultivating their exploratory ability.As the future practitioners of kindergarten education,preschool education majors in colleges and universities are now actively exploring the implementation strategies of kindergarten nature education programs and innovating the construction method of nature education programs,which not only directly affects the high quality of their future teaching work,but also helps to promote the cognitive development of young children and the enhancement of their practical skills.Based on this,this paper outlines the teaching strategies of a kindergarten nature education program from the perspective of letting young children get close to nature,discovering nature,and other aspects of preschool education majors in colleges and universities.
基金support from the National Natural Science Foundation of China(62204015)the Beijing Natural Science Foundation(L223006).
文摘Infrared optoelectronic sensing is the core of many critical applications such as night vision,health and medication,military,space exploration,etc.Further including mechanical flexibility as a new dimension enables novel features of adaptability and conformability,promising for developing next-generation optoelectronic sensory applications toward reduced size,weight,price,power consumption,and enhanced performance(SWaP^(3)).However,in this emerging research frontier,challenges persist in simultaneously achieving high infrared response and good mechanical deformability in devices and integrated systems.Therefore,we perform a comprehensive review of the design strategies and insights of flexible infrared optoelectronic sensors,including the fundamentals of infrared photodetectors,selection of materials and device architectures,fabrication techniques and design strategies,and the discussion of architectural and functional integration towards applications in wearable optoelectronics and advanced image sensing.Finally,this article offers insights into future directions to practically realize the ultra-high performance and smart sensors enabled by infrared-sensitive materials,covering challenges in materials development and device micro-/nanofabrication.Benchmarks for scaling these techniques across fabrication,performance,and integration are presented,alongside perspectives on potential applications in medication and health,biomimetic vision,and neuromorphic sensory systems,etc.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(2020A1515110608)Department of Education of Guangdong Province-Guangdong Province General University Youth Innovative Talent Project(2019KQNCX039).
文摘Background:Childhood environmental unpredictability(CEU)is crucial to personal development,profoundly influence physical and psychological growth particularly,and psychopathy is recognized as a dark personality trait.The aim of this study is to investigate the effects of insecure attachment and life history strategy(LHS)on the relationship between CEU and psychopathy by establishing a sequential mediation model based on evolutionary life history theory and cognitive-affective personality system.Methods:A group of 532 undergraduates completed the measurements for CEU,insecure attachment,LHS,and psychopathy,and Bootstrap mediation test through SPSS 25.0 and PROCESS macro tool was used to examine the relationship among these variables.Results:The results revealed positive relations between CEU and insecure attachment(β=0.87,p<0.001),CEU and LHS(β=0.11,p<0.001),and CEU and psychopathy(β=0.14,p<0.001).Insecure attachment was also positively associated with LHS(β=0.62,p<0.001)and psychopathy(β=0.04,p<0.001).In addition,LHS was significantly associated with psychopathy(β=0.08,p<0.001).The relationship between CEU and psychopathy is mediated independently and sequentially by insecure attachment and LHS.Conclusion:The current research shows the relationship between CEU and psychopathy,as well as the mechanism of insecure attachment and life history strategy as mediators.