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Innovation and Development Policy(中文名:《创新与发展政策(英文)》)征稿启事
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《科研管理》 北大核心 2026年第1期F0004-F0004,共1页
Innovation and Development Policy,简称“IDP”,中文名:《创新与发展政策(英文)》,是由中国科学院主管,中国科学院科技战略咨询研究院、中国科学学与科技政策研究会共同主办,国内外发行(ISSN:2096-5141,CN:10-1513/D)的英文国际期刊... Innovation and Development Policy,简称“IDP”,中文名:《创新与发展政策(英文)》,是由中国科学院主管,中国科学院科技战略咨询研究院、中国科学学与科技政策研究会共同主办,国内外发行(ISSN:2096-5141,CN:10-1513/D)的英文国际期刊。目前期刊每年出版两期。已发表论文在期刊网站可以自由获取,http://idp-journal.casisd.cn/browse/al/al2019/。 展开更多
关键词 创新与发展政策 Innovation and Development policy
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Orientation-and wavelength-dependent sperm motility in optical trapping
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作者 Juan Wang Jifu Lyu +8 位作者 Haoyu Pan Xinyu Fan Xiang Jiang Xuhui Bao Yi Wang Fengya Lu Zhiguo Zhang Zhensheng Zhong Jinhua Zhou 《Journal of Innovative Optical Health Sciences》 2026年第2期54-68,共15页
Optical tweezers technology has the characteristics of noncontact manipulation in three dimensions and steerable separation in solutions,and could be applied to obtain a separated sperm with high quality for intracyto... Optical tweezers technology has the characteristics of noncontact manipulation in three dimensions and steerable separation in solutions,and could be applied to obtain a separated sperm with high quality for intracytoplasmic sperm injection(ICSI).However,the effects of optical tweezers on sperm motility are still unclear.To elucidate the effects on sperm motility for optical tweezers,we systematically investigated the correlation between motility parameters and the parameters of optical tweezers(wavelength,power,trapping duration,and trapping orientation).Under three systems of optical tweezers with different laser wavelengths(1064,850,and 785 nm),the nine motility parameters of free swimming were mainly affected by trapping orientation(vertical/horizontal)and trapping duration.When 850 nm laser and 1064 nm laser are used,vertical trapping significantly reduces sperm free-swimming capability with prolonged exposure time,whereas horizontal trapping exhibits relatively minor interference on sperm motility.Notably,the 785 nm laser does not induce statistically significant changes in key parameters of sperm motility under any experimental conditions(trapping orientation and duration).For the rolling frequency of trapped sperm,horizontal trapping for three wavelengths has a negligible effect compared with vertical trapping,especially for the 785 nm laser.In conclusion,horizontal trapping can preserve sperm motility under low power(below 140mW at 1064 nm,below 100mW at 850nm,below 60mW at 785 nm)and short duration(below 4 min).This trapping duration is suffcient for the separation procedure of single live sperm in ICSI.This study provides critical parameter optimization guidelines for the safe application of optical tweezers technology in reproductive medicine. 展开更多
关键词 Optical tweezers SPERM wavelength trapping duration trapping orientation
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The Relationship between Peer Victimization and Non-Suicidal Self-Injury Behavior among Middle School Students:The Mediating Role of Future Orientation and Social Withdrawal
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作者 Biao Li Xiao Hu +1 位作者 Pengzhan Wei Yunbin Deng 《International Journal of Mental Health Promotion》 2026年第2期157-170,共14页
Objectives:Non-suicidal self-injury(NSSI)represents a prominent and escalating concern within mental health,associated with considerable psychological and physical dangers.Peer victimization is identified as a signifi... Objectives:Non-suicidal self-injury(NSSI)represents a prominent and escalating concern within mental health,associated with considerable psychological and physical dangers.Peer victimization is identified as a significant predictor of NSSI behavior.Although prior research has explored the association between peer victimization and NSSI,the mechanisms underlying this relationship remain insufficiently understood.Utilizing social information processing theory frameworks,the present study seeks to examine the sequential mediating roles of a cognitive factor,future orientation,and a behavioral factor,social withdrawal,in middle school students.Methods:A cross-sectional survey was administered in China,involving 528 participants(261 females and 267 males;Meanage=13.71,standard deviation[SD]=0.93).Participants completed self-report measures assessing peer victimization via the Delaware Bullying Victimization Scale-Student Version,NSSI via the Adolescents Self-Harm Scale,future orientation via the Adolescent Future Orientation Questionnaire,and social withdrawal via the Social Withdrawal Questionnaire.Results:Findings indicated a significant positive correlation between peer victimization and NSSI(r=0.30,p<0.01).Additionally,future orientation and social withdrawal functioned as serial mediators,with an indirect effect of 0.01(95%CI:[0.01,0.02]),representing 2.70%of the total effect(𝛽=0.37,95%CI:[0.25,0.47]).Conclusions:The findings endorse a theoretical framework in which negative future outlook and social withdrawal are sequentially linked within the relationship between peer victimization and NSSI.Although the serial indirect effect observed is modest,it delineates a distinct associative pattern that characterizes adolescents subjected to victimization.These results carry practical significance for school-based intervention programs,indicating that targeting future perspectives and social connections may enhance strategies for preventing NSSI. 展开更多
关键词 Peer victimization non-suicidal self-injurious future orientation social withdrawal
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Chengdu’s Real Estate Market(2019-2024):An Integrated Framework for Data-Driven Insights and Policy Analysis
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作者 HU Xiao WU Jing +1 位作者 WANG Yan JIANG Xinyi 《Cultural and Religious Studies》 2026年第1期26-42,共17页
This study integrates multiple sources of data(transaction data,policy text,public opinion data)with visualization techniques(such as heat maps,time-series trend charts,3D building brochures)to construct an analysis f... This study integrates multiple sources of data(transaction data,policy text,public opinion data)with visualization techniques(such as heat maps,time-series trend charts,3D building brochures)to construct an analysis framework for the Chengdu real estate market.By using the Adaptive Neuro-Fuzzy Inference System(ANFIS)prediction model,spatial GIS(Geographic Information System analysis)analysis,and interactive dashboards,this study reveals market differentiation,policy impacts,and changes in demand structure,thereby providing decision support for the government,enterprises,and homebuyers. 展开更多
关键词 Chengdu City real estate market data-driven insights policy analysis
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Effects of initial spin orientation on the generation of polarized electron beams from laser wakefield acceleration in plasma
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作者 L.R.Yin X.F.Li +6 位作者 Y.J.Gu N.Cao Q.Kong M.Büscher S.M.Weng M.Chen Z.M.Sheng 《Matter and Radiation at Extremes》 2026年第1期20-28,共9页
The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of... The effects of initial spin orientation on the final electron beam polarization in laser wakefield acceleration in a pre-polarized plasma are investigated theoretically and numerically.From the results of variation of the initial spin direction,the spin dynamics of the electron beam are found to depend on the self-injection mechanism.The effects of wakefields and laser fields are studied using test particle dynamics and particle-in-cell simulations based on the Thomas-Bargmann-Michel-Telegdi equation.Compared with transverse injection,longitudinal injection is found to be preferable for obtaining a highly polarized electron beam. 展开更多
关键词 spin dynamics laser fields test particle dynamics initial spin orientation electron beam laser wakefield acceleration electron beam polarization
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基于Off-policy Q-学习的时延系统线性二次型跟踪控制算法
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作者 刘文 蔚保国 +1 位作者 郝菁 王卿 《无线电工程》 2026年第1期166-176,共11页
对被控系统数学模型参数未知的线性离散时间系统,同时考虑工业过程中数据存在控制输入时间延时的问题,提出一种数据驱动算法,解决时延系统线性二次型跟踪(Linear Quadratic Tracking,LQT)控制问题。通过对时延系统控制问题的描述,构建... 对被控系统数学模型参数未知的线性离散时间系统,同时考虑工业过程中数据存在控制输入时间延时的问题,提出一种数据驱动算法,解决时延系统线性二次型跟踪(Linear Quadratic Tracking,LQT)控制问题。通过对时延系统控制问题的描述,构建了基于模型驱动的强化学习算法框架,在此基础上为了避免使用数学模型参数和状态数据信息,引入Smith预估器,提出了基于On-policy Q-学习的时延系统LQT控制算法。考虑On-policy Q-学习算法中探测噪声对学习结果的影响,进一步采用Off-policy算法解决时延系统LQT控制问题。在此基础上改进Q-学习算法中使用的Bellman方程,提出数据驱动的Off-policy Q-学习算法,该算法不受探测噪声的影响,求解得到的解是无偏差的。理论分析和仿真实验表明,在避免依赖系统数学模型参数和状态数据的前提下,有效实现了时延系统的跟踪控制。 展开更多
关键词 时延系统 强化学习 Off-policy 数据驱动 输出反馈
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Research on the Policy Orientation of Government in Agricultural Industrialization Development 被引量:1
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作者 HUANG Hong-qiu 《Asian Agricultural Research》 2011年第1期7-10,33,共5页
Governmental functions in agricultural industrialization management are analyzed, mainly including supplying public products, providing property right security, managing and protecting resources and environment as wel... Governmental functions in agricultural industrialization management are analyzed, mainly including supplying public products, providing property right security, managing and protecting resources and environment as well as stabilizing the agro-product market. The policy orientation promoted by the government in agricultural industrialization management is pointed out: formulating a series of macro-management planning to guide and regulate agricultural industrialization operation; fully playing the comprehensive coordinating role of "economic manager"; making and carrying out relevant laws and regulations to normalize the implementation of agricultural industrialization management. To implement the industrial management of agriculture and promote the construction of new countryside, governments at all levels should eliminate the institutional barriers, transform governmental functions gradually and prioritize planning, regulation, service and supervision, changing from merely management to playing the role of market mechanism. Meanwhile, economic, legal and administrative means should be properly adopted to advance the industrial management and the healthy improvement of modern agriculture. 展开更多
关键词 GOVERNMENT Agricultural industrialization policy orientation China
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Micro-reconstruction Strategies of Urban Villages in Small Towns from the Perspective of Policy Orientation:A Case Study of Zhuangqian Xiongjia Village,Fengcheng City
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作者 WU Na FAN Qindan 《Journal of Landscape Research》 2023年第4期41-44,49,共5页
As China’s economy shifts from high-speed development to high-quality development,China’s urbanization also shifts from incremental expansion to stock optimization,providing a new direction for the transformation of... As China’s economy shifts from high-speed development to high-quality development,China’s urbanization also shifts from incremental expansion to stock optimization,providing a new direction for the transformation of urban villages.At present,the reconstruction work office of urban villages in small towns is mainly promoted based on government-led and villager main body in the initial exploration stage.From the perspective of policy orientation,to solve the main problems in urban villages in small towns,Zhuangqian Xiongjia Village,Fengcheng City was taken as an example,and the micro-transformation strategies of urban villages were put forward from the perspective of satisfying the appeals of the government,village committee and villagers,so as to provide some references for the transformation of urban villages in other small towns across the country. 展开更多
关键词 policy orientation Urban village in a small town Micro-transformation strategies
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Reflection on the Basic Orientation of China's Policy-Oriented Financial System
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作者 JIA Kang MENG Yan 《当代财经》 CSSCI 北大核心 2013年第S1期50-56,共7页
At present stage,active exploration and healthy development of China’s policy-oriented financial system is hindered by such problems as unclear understanding of policy finance,dislocation of the functions of policy b... At present stage,active exploration and healthy development of China’s policy-oriented financial system is hindered by such problems as unclear understanding of policy finance,dislocation of the functions of policy banks and so on.While sticking to pushing forward the reforms of market-oriented financial system and fully improving the efficiency of the financial system,we must correctly handle the relationship between policy finance and commercial finance,re-examine the position and role of policy finance in the entire financial system of the country,take the policy-oriented financial system as one of the important parts of financing of the social funds,make up and fill in reasonably the"intermediate zone"between the direct fiscal expenditures and commercial financing,pursue the transition of the mechanism relying on government financial resources,realize the multiplexing effect of efficiency promotion,serve the comprehensive,coordinated,sustainable and unified development required by the concept of scientific development and catching-up and breakthrough at some strategic focuses. 展开更多
关键词 policy-oriented FINANCIAL SYSTEM commercial FINANCIAL SYSTEM policy BANK REFORM
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MAKING CLEAR STRATEGIC PRIORITIES, STRENGTHENING POLICY ORIENTATION AND PROMOTING INSTITUTIONAL ADJUSTMENT
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作者 Lu Yongxiang(The Chinese Academy of Sciences) 《Bulletin of the Chinese Academy of Sciences》 1995年第2期116-121,共6页
Ⅰ. CURRENT DEVELOPMENT AND FUTURE TASKS The period from the "Ninth Five-Year Plan"(1990-2000) to the year 2010 is the key stage for realizing the three-step strategy for economic construction in China. The ... Ⅰ. CURRENT DEVELOPMENT AND FUTURE TASKS The period from the "Ninth Five-Year Plan"(1990-2000) to the year 2010 is the key stage for realizing the three-step strategy for economic construction in China. The socialist market economy system will gradually develop to perfection,the market will play a fundamental role in allocating resources,and the State’s centralizing guidance and macro-control over the social and economic development will be more scientific,reasonable and effective.In recent years,despite of 展开更多
关键词 CAS MAKING CLEAR STRATEGIC PRIORITIES STRENGTHENING policy orientation AND PROMOTING INSTITUTIONAL ADJUSTMENT WILL high
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Simulation Analysis of Macroeconomic Policy Orientations' Effects on the Industrial Economy——Based on Dynamic CGE Model
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作者 原磊 王秀丽 《China Economist》 2014年第2期100-112,共13页
There are three different orientations of the macroeconomic policies,namely,factor-expansion,prudent-continuation and structural-adjustment.The paper uses the dynamic CGE model to simulate the effects of the three dif... There are three different orientations of the macroeconomic policies,namely,factor-expansion,prudent-continuation and structural-adjustment.The paper uses the dynamic CGE model to simulate the effects of the three different orientations on the economy,and arrives at the following conclusions:while the factor-expansion policies can lead to growth of economic output,they also result in the further imbalance in the industrial structure and the "crowding-out effect" on the private investment.In addition,such growth is unsustainable in the long run;the growth of the industrial economy will decline rapidly to a lower level after reaching a certain high level.The prudent-continuation policies refer to the continuation of the current policies that sustain the current trends of the industrial economy,and such policies reduce the growth of the industrial economy to a lower level in the long run.The structural-adjustment policies reduce the economic output at the current stage;however,it can bring a gradual improvement of industrial structure and a balance of the supply and demand.In the long run,the optimized structure will improve the total factor productivity(TFP) and the production-possibility frontier,and thereby realize a longterm steady and rapid growth of the industrial economy.Four policy recommendations are proposed based on the simulation of the models,including taking the structural adjustment as the fundamental orientation of macroeconomic policies,lowering the "floor level" of economic growth with macro regulation,giving play to the fundamental role of market mechanism in structural adjustment and increasing the role of TFP in the growth of the industrial economy. 展开更多
关键词 dynamic CGE model factor-expansion policies prudent-continuationpolicies structural-adjustment policies
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An Analysis of Donald Trump's Political Personality Traits and Policy Orientations
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作者 Yin Jiwu Zheng Jianjun Li Hongzhou 《Contemporary International Relations》 2017年第2期82-91,共10页
As a political leader, US President Trump's personality traits affect his policy orientations and current US foreign policy. The authors analyze Trump's personality in several categories—uninhibited and capri... As a political leader, US President Trump's personality traits affect his policy orientations and current US foreign policy. The authors analyze Trump's personality in several categories—uninhibited and capricious, dynamic and capable, profit-orientated and self-centered,competitive and persistent, positive and extraverted. The traits of breaking traditions, skill at strategic deception and negotiation, action-motivated implementation, intuitive decision-making, pursuit of respect and interest exchange, and vengefulness will shape his policy and behavioral orientations. Initial study shows Trump to be a political leader with positive personality traits and double-sided dimensions. The analysis offers insight toward understanding the new US executive and his policy direction. 展开更多
关键词 Donald Trump personality traits policy preference US
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The Cyberpsychology of Small and Medium-Sized Enterprises Cybersecurity: A Human-Centric Approach to Policy Development 被引量:1
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作者 Troy C. Troublefield 《Journal of Information Security》 2025年第1期158-183,共26页
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
关键词 Cyberpsychology CYBERSECURITY SMES policy Development Human Factors Risk Perception Compliance Behavior Organizational Culture Psychological Resilience Security Awareness
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The Policy for Education of Migrant Workers' Children:Situation Analysis and the Future Orientation
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作者 Liu Yanli Tang Yaner 《International English Education Research》 2015年第9期70-72,共3页
The education of migrant workers' children is not only education but also social issue. Countries and places have introduced a number of policies to address the issue in a timely manner. At first, this paper analyzes... The education of migrant workers' children is not only education but also social issue. Countries and places have introduced a number of policies to address the issue in a timely manner. At first, this paper analyzes the compulsory education policy for migrant workers' children and off-site college entrance policy, then find that there are still many problems in the formulation and implementation of policy. In the future, the relevant departments should be through improving the social status of migrant workers, increasing efforts to support the private school children of migrant workers, increasing investment in adult education, increasing the publicity of city, such the four aspects of policy guidance to coordinate and solve the education of migrant workers' children. 展开更多
关键词 Migrant works' children Compulsory Education Off-site College Entrance Examination policy
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Integrating well logs,3D seismic,and earthquake data for comprehensive prediction of 3D in-situ stress orientations:A case study from the Weiyuan area in the Sichuan Basin,China 被引量:1
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作者 Huan Cao Yang Zhao +4 位作者 Hai-Chao Chen Le-Le Zhang Cheng-Gang Xian Ji-Dong Yang Lu Liu 《Petroleum Science》 2025年第1期210-221,共12页
Determining the orientation of in-situ stresses is crucial for various geoscience and engineering appli-cations.Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(F... Determining the orientation of in-situ stresses is crucial for various geoscience and engineering appli-cations.Conventional methods for estimating these stress orientations often depend on focal mechanism solutions(FMSs)derived from earthquake data and formation micro-imager(FMI)data from well logs.However,these techniques can be costly,depth-inaccurate,and may lack spatial coverage.To address this issue,we introduce the use of three-dimensional(3D)seismic data(active sources)as a lateral constraint to approximate the 3D stress orientation field.Recognizing that both stress and fracture patterns are closely related to seismic velocity anisotropy,we derive the orientation of azimuthal anisotropy from multi-azimuth 3D seismic data to compensate for the lack of spatial stress orientation information.We apply our proposed workflow to a case study in the Weiyuan area of the Sichuan Basin,China,a region targeted for shale gas production.By integrating diverse datasets,including 3D seismic,earthquakes,and well logs,we develop a comprehensive 3D model of in-situ stress(orientations and magnitudes).Our results demonstrate that the estimated anisotropy orientations from 3D seismic data are consistent with the direction of maximum horizontal principal stress(SHmax)obtained from FMIs.We analyzed 12 earthquakes(magnitude>3)recorded between 2016 and 2020 for their FMSs and compressional axis(P-axis)orientations.The derived SHmax direction from our 3D stress model is 110°ES(East-South),which shows excellent agreement with the FMSs(within 3.96°).This close alignment validates the reliability and precision of our integrated method for predicting 3D SHmax orientations. 展开更多
关键词 In-situ stress orientation SHmax Azimuthal velocity anisotropy Focal source mechanism Formation micro-imager
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Breaking down the barriers to clean air:The effects of China’s Zero-Waste City policy on PM_(2.5)concentration 被引量:2
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作者 Wei Wang 《Chinese Journal of Population,Resources and Environment》 2025年第1期75-84,共10页
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
关键词 Zero-Waste City pilot policy PM_(2.5) Green innovation Green economy Sustainable development Difference-in-differences model
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Financial Policy Orientation to Realize Sustainable Development of Forestry
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作者 CHENXiaohui 《外文科技期刊数据库(文摘版)经济管理》 2022年第4期118-121,共4页
The sustainable development of forestry can reflect the development level of forestry productivity, fully reflect the degree of social ecological civilization, and at the same time can meet the diverse needs of the so... The sustainable development of forestry can reflect the development level of forestry productivity, fully reflect the degree of social ecological civilization, and at the same time can meet the diverse needs of the society. It is helpful to promote the construction of an environment-friendly society and the harmonious development of man and nature. The important way to realize the sustainable development of forestry is classified management. The national forestry financial policy should focus on public finance and consider various factors. This paper expounds the goal of forestry sustainable development, analyzes the characteristics of capital operation under forestry classified management, and puts forward suggestions on financial policies for realizing forestry sustainable development, hoping to provide reference for relevant research. 展开更多
关键词 FORESTRY sustainable development fiscal policy
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Influence of orientation of the intermediate principal stress on fracture reactivation in granite 被引量:1
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作者 Wei Wang Fanzhen Meng +6 位作者 Zhufeng Yue Guanghao Cui Qijin Cai Zhiyuan Li Dongliang Tian Hui Zhou Zaiquan Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期859-876,共18页
Fracture(fault)reactivation can lead to dynamic geological hazards including earthquakes,rock collapses,landslides,and rock bursts.True triaxial compression tests were conducted to analyze the fracture reactivation pr... Fracture(fault)reactivation can lead to dynamic geological hazards including earthquakes,rock collapses,landslides,and rock bursts.True triaxial compression tests were conducted to analyze the fracture reactivation process under two different orientations of σ_(2),i.e.σ_(2) parallel to the fracture plane(Scheme 2)and σ_(2) cutting through the fracture plane(Scheme 3),under varying σ_(3) from 10 MPa to 40 MPa.The peak or fracture reactivation strength,deformation,failure mode,and post-peak mechanical behavior of intact(Scheme 1)and pre-fractured(Schemes 2 and 3)specimens were also compared.Results show that for intact specimens,the stress remains nearly constant in the residual sliding stage with no stick-slip,and the newly formed fracture surface only propagates along the σ_(2) direction when σ_(3) ranges from 10 MPa to 30 MPa,while it extends along both σ_(2) and σ_(3) directions when σ_(3) increases to 40 MPa;for the pre-fractured specimens,the fractures are usually reactivated under all the σ_(3) levels in Scheme 2,but fracture reactivation only occurs when σ_(3) is greater than 25 MPa in Scheme 3,below which new faulting traversing the original macro fracture occurs.In all the test schemes,both ε_(2) and ε_(3) experience an accumulative process of elongation,after which an abrupt change occurs at the point of the final failure;the degree of this change is dependent on the orientation of the new faulting or the slip direction of the original fracture,and it is generally more than 10 times larger in the slip direction of the original fracture than in the non-slip direction.Besides,the differential stress(peak stress)required for reactivation and the post-peak stress drop increase with increasing σ_(3).Post-peak stress drop and residual strength in Scheme 3 are generally greater than those in Scheme 2 at the same σ_(3) value.Our study clearly shows that intermediate principal stress orientation not only affects the fracture reactivation strength but also influences the slip deformation and failure modes.These new findings facilitate the mitigation of dynamic geological hazards associated with fracture and fault slip. 展开更多
关键词 True triaxial Fracture reactivation Intermediate principal stress orientation Minimum principal stress levels Computed tomography
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财政科技政策实施特征与科技成果转化 被引量:1
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作者 刘大勇 李妍 +1 位作者 王孟柔 胡秋阳 《科学学研究》 北大核心 2026年第1期178-193,共16页
畅通科技成果转化通道,将科技成果转化为现实生产力,离不开财政政策的有效支持和精准发力。基于政策实施视角,研究构建了财政科技政策实施特征影响地区科技成果转化的理论分析框架,并基于城市层面的样本数据实证考察了相应的作用效果。... 畅通科技成果转化通道,将科技成果转化为现实生产力,离不开财政政策的有效支持和精准发力。基于政策实施视角,研究构建了财政科技政策实施特征影响地区科技成果转化的理论分析框架,并基于城市层面的样本数据实证考察了相应的作用效果。论证指出:政府增强财政科技政策实施力度有助于促进科技成果转化;当政策指向性较强,以科技成果转化为政策实施目标时,有助于推动成果转化相关的服务完善及创新资源集聚,从而有效促进科技成果转化;当政策稳定性较强,为市场主体提供持续稳定的政策环境时,有助于提升市场主体的预期,进而更加有效地促进科技成果转化。基于不同市场条件的作用分析表明,当地区科技创新基础较强时,提升财政科技政策实施力度可以更显著地促进科技成果转化:当地区技术市场活跃度较高,对技术创新和转化的需求较充分时,财政科技政策实施力度对科技成果转化的促进作用更明显。研究可以为深入理解财政科技政策的实施特征及其对科技成果转化的作用效果提供理论支持,并为政府制定和实施财政科技政策提供实践参考。 展开更多
关键词 财政科技政策 政策实施特征 科技成果转化 政策指向性 政策稳定性
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Deep reinforcement learning based integrated evasion and impact hierarchical intelligent policy of exo-atmospheric vehicles 被引量:1
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作者 Leliang REN Weilin GUO +3 位作者 Yong XIAN Zhenyu LIU Daqiao ZHANG Shaopeng LI 《Chinese Journal of Aeronautics》 2025年第1期409-426,共18页
Exo-atmospheric vehicles are constrained by limited maneuverability,which leads to the contradiction between evasive maneuver and precision strike.To address the problem of Integrated Evasion and Impact(IEI)decision u... Exo-atmospheric vehicles are constrained by limited maneuverability,which leads to the contradiction between evasive maneuver and precision strike.To address the problem of Integrated Evasion and Impact(IEI)decision under multi-constraint conditions,a hierarchical intelligent decision-making method based on Deep Reinforcement Learning(DRL)was proposed.First,an intelligent decision-making framework of“DRL evasion decision”+“impact prediction guidance decision”was established:it takes the impact point deviation correction ability as the constraint and the maximum miss distance as the objective,and effectively solves the problem of poor decisionmaking effect caused by the large IEI decision space.Second,to solve the sparse reward problem faced by evasion decision-making,a hierarchical decision-making method consisting of maneuver timing decision and maneuver duration decision was proposed,and the corresponding Markov Decision Process(MDP)was designed.A detailed simulation experiment was designed to analyze the advantages and computational complexity of the proposed method.Simulation results show that the proposed model has good performance and low computational resource requirement.The minimum miss distance is 21.3 m under the condition of guaranteeing the impact point accuracy,and the single decision-making time is 4.086 ms on an STM32F407 single-chip microcomputer,which has engineering application value. 展开更多
关键词 Exo-atmospheric vehicle Integrated evasion and impact Deep reinforcement learning Hierarchical intelligent policy Single-chip microcomputer Miss distance
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