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ANALYSIS OF CELL-AVERAGING BASED DETECTORS FOR χ^2 FLUCTUATING TARGETS IN MULTITARGET ENVIRONMENTS 被引量:1
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作者 Mohamed B. El_Mashade 《Journal of Electronics(China)》 2006年第6期853-863,共11页
The χ^2 family of signal fluctuation distributions represents the main fluctuation models which most radar targets follow it in their reflections. This family can be categorized as fluctuation distribution with two d... The χ^2 family of signal fluctuation distributions represents the main fluctuation models which most radar targets follow it in their reflections. This family can be categorized as fluctuation distribution with two degrees of freedom and those with four degrees of freedom. The first category represents all important class of fluctuation models which when illuminated by a coherent pulse train, return a train of fully correlated pulses (Swerling Ⅰ model) or fully decorrelated pulses (Swerling Ⅱ model). The detection of this type of fluctuating targets is therefore of great importance. This paper is devoted to the analysis of Cell-Averaging (CA) based detectors for the case where the radar receiver noncoherently integrates M square-law detected pulses and the signal fluctuation obeys 2 statistics with two degrees of freedom. These detectors include the Mean-Of (MO), the Greatest-Of (GO) and the Smallest-Of(SO) schemes. In these processors, the estimation of the noise power levels from the leading and the trailing reference windows is based on the CA technique. Exact formulas for the detection probabilities are derived, in the absence as well as in the presence of spurious targets. The primary and the secondary interfering targets are assumed to be fluctuating in accordance with the χ^2 fluctuation model with two degrees of freedom (SWI & SWII). The numerical results show that the MO version has the best homogeneous performance, the SO scheme has the best multiple-target performance, while the GO procedure does not offer any merits, neither in the absence nor in the presence of outlying targets. 展开更多
关键词 Adaptive detectors Cell-averaging processors Noncoherent integration χ^2 fluctuating targets target multiplicity environments
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Influence of local environmental target constraints on enterprise OFDI
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作者 DING Qi-nan ZHOU Quan GAO Hong-gui 《Ecological Economy》 2022年第1期2-17,共16页
By collecting the environmental target constraints in the annual government work report of prefecture-level cities,this paper studies its impact on local enterprises’OFDI.The main conclusions are as follows:(1)Both d... By collecting the environmental target constraints in the annual government work report of prefecture-level cities,this paper studies its impact on local enterprises’OFDI.The main conclusions are as follows:(1)Both direct and indirect constraints have a significant positive impact on enterprises’OFDI,and the degree of direct constraints is stronger than that of indirect constraints.(2)Environmental target constraints of local governments will affect corporate OFDI behavior by affecting production costs,local economic development level and local openness,and(3)There are regional heterogeneity and investment type heterogeneity in the impact of environmental goal constraints on corporate OFDI.The suggestions are as follows:government departments can appropriately strengthen the constraint intensity of environmental targets and formulate specific restraint rules for industries with different levels of pollution,so as to effectively make use of the technology spillover effects brought about by OFDI to promote the upgrading of domestic industrial structure.When making OFDI,enterprises should clarify the investment motivation,strengthen corporate social responsibility,and make use of technology spillover effect to promote the upgrading and development of home country industry while being beneficial to their own development. 展开更多
关键词 local environmental target constraint environmental regulation outward foreign direct investment
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Heterogeneous performance analysis of the new model of CFAR detectors for partially-correlated χ~2-targets
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作者 EL_MASHADE Mohamed Bakry 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第1期1-17,共17页
To mitigate the deleterious effects of clutter and jammer, modern radars have adopted adaptive processing techniques such as constant false alarm rate(CFAR) detectors which are widely used to prevent clutter and noise... To mitigate the deleterious effects of clutter and jammer, modern radars have adopted adaptive processing techniques such as constant false alarm rate(CFAR) detectors which are widely used to prevent clutter and noise interference from saturating the radar’s display and preventing targets from being obscured.This paper concerns with the detection analysis of the novel version of CFAR schemes(cell-averaging generalized trimmed-mean,CATM) in the presence of additional outlying targets other than the target under research. The spurious targets as well as the tested one are assumed to be fluctuating in accordance with the χ~2-model with two-degrees of freedom. In this situation, the processor performance is enclosed by the swerling models(SWI and SWII). Between these bounds, there is an important class of target fluctuation which is known as moderately fluctuating targets. The detection of this class has many practical applications. Structure of the CATM detector is described briefly. Detection performances for optimal, CAM, CA, trimmed-mean(TM) and ordered-statistic(OS) CFAR strategies have been analyzed and compared for desired probability of false alarm and determined size of the reference window. False alarm rate performance of these processors has been evaluated for different strengths of interfering signal and the effect of correlation among the target returns on the detection and false alarm performances has also been studied. Our numerical results show that, with a proper choice of trimming parameters,the novel model CAM presents an ideal detection performance outweighing that of the Neyman-Pearson detector on condition that the tested target obeys the SWII model in its fluctuation. Although the new models CAS and CAM can be treated as special cases of the CATM algorithm, their multi-target performance is modest even it has an enhancement relative to that of the classical CAcheme. Additionally, they fail to maintain the false alarm rate constant when the operating environment is of type target multiplicity. Moreover, the non-coherent integration of M pulses ameliorates the processor performance either it operates in homogeneous or multi-target environment. 展开更多
关键词 adaptive target detection multi-pulse performance noise and interference partially-correlated χ~2-targets SWI & SWII target fluctuation models target multiplicity environments
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环境目标约束对地方政府清洁生产型行业土地出让的影响
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作者 卢娜 刘轩 +2 位作者 冯淑怡 刘志荣 刘子铭 《中国人口·资源与环境》 CSSCI CSCD 北大核心 2024年第7期146-157,共12页
土地资源配置对产业发展具有重要的引导和支撑作用,优化配置工业用地对中国实现发展方式绿色转型发挥着重要的基础性作用。该研究从环境政策与地方领导干部政绩考核相结合的视角,以2007—2020年中国280个地级市的面板数据作为研究样本,... 土地资源配置对产业发展具有重要的引导和支撑作用,优化配置工业用地对中国实现发展方式绿色转型发挥着重要的基础性作用。该研究从环境政策与地方领导干部政绩考核相结合的视角,以2007—2020年中国280个地级市的面板数据作为研究样本,分别采用固定效应模型、工具变量法、中介效应模型实证检验了环境目标约束对地方政府清洁生产型行业土地出让的影响及其作用机制,并进一步采用调节效应模型分析了地方政府面临的经济增长压力和财政压力所发挥的调节作用。研究结果表明:①环境目标约束能够显著促进地方政府增加清洁生产型行业土地出让,该结果在经过内生性处理和多种稳健性检验后依然成立。从土地供应政策、产业结构和领导干部特征差异性视角来看,分别在土地供给充裕、工业主导、在任市长非本地来源、在任市长年龄≤55岁的城市,环境目标约束对地方政府增加清洁生产型行业土地出让的促进作用显著。②机制分析发现,环境目标约束会促使地方政府通过提升环境规制强度、加大环境治理监管力度等途径增加清洁生产型行业土地出让。③进一步研究发现,地方政府面临的经济增长压力会削弱环境目标约束对其清洁生产型行业土地出让的促进作用,而财政压力则与环境目标约束的促进作用具有协同作用。以上结论表明中央实施的环境目标“硬约束”政策已促使地方政府在工业用地出让时向绿色产业偏向性配置,为中国实现环境污染治理和资源优化配置的“双赢”提供了重要的现实证据。 展开更多
关键词 环境目标约束 土地出让 清洁生产型行业 经济增长压力 财政压力
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Defining a mountain landscape characterized by grazing using actor perception, governmental strategy, and environmental monitoring data
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作者 Wiebke NEUMANN Camilla SANDSTROM +1 位作者 Lina HOLMGREN Goran ERICSSON 《Journal of Mountain Science》 SCIE CSCD 2019年第7期1691-1701,共11页
In multi-functional mountainous landscapes worldwide,conservation of natural values is a major task.Here,pro-active policies can be a way forward.National Environmental Quality Objectives(EQO)to solve environmental pr... In multi-functional mountainous landscapes worldwide,conservation of natural values is a major task.Here,pro-active policies can be a way forward.National Environmental Quality Objectives(EQO)to solve environmental problems for future generations,however,often wrestle with being too visionary and lacking specificity,which complicates their implementation.The EQO“A Magnificent Mountain Landscape”that has been adopted by the Swedish Parliament in 1999 to preserve the pristine mountain environment in Sweden,experiences all these flaws.To aid its implementation,we studied the conditions and processes needed to define,to evaluate,and to preserve its goals across the Swedish mountain chain,using one of its milestone targets(a landscape characterized by grazing)as a study system.Applying qualitative and quantitative methods,we analyzed three types of data:1)referral responses to the governmental strategy document,2)interviews with relevant actors,and 3)environmental monitoring data(reindeer position data).Nationally,our results suggest a need for geographical differentiation to match regional/local conditions.Regionally,difference in both perception and definition of the milestone target among the actors hinders the formulation,monitoring,and evaluation of a common goal.Next to a culture-nature divide,we found that a“within as a user”and“from the outside as an observer”perspective influenced suggested definitions.Moreover,we found a need for better defining whether the goal is maintaining current conditions or restoring previous ones.Our result supports the use of animal position data as a decision support tool to monitor and to aid evaluation of the target.Given the number of actors involved and conflicts of interests present,we suggest the application of a structured decision process to accomplish agreements on a common goal.Here,environmental monitoring data can aid a“landscape assessment step”as a natural part in the decision process to target landscape management actions resourcefully and effectively. 展开更多
关键词 Milestone target Structured decision process REINDEER HERDING HERBIVORY environmentAL Conservation STRATEGY Sweden
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基于能动司法视角的蓝碳治理环境司法探讨
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作者 邢鸿飞 庄潇 《水利经济》 北大核心 2024年第5期47-53,共7页
在系统梳理相关规范体系和实践现状的基础上,分析了蓝碳治理的司法困境及成因,探讨了环境司法能动助力蓝碳治理的路径。结果表明:我国蓝碳存在司法适用规范阙如、司法权与行政权配置不合理、司法能动与克制的标准不明、责任承担方式各... 在系统梳理相关规范体系和实践现状的基础上,分析了蓝碳治理的司法困境及成因,探讨了环境司法能动助力蓝碳治理的路径。结果表明:我国蓝碳存在司法适用规范阙如、司法权与行政权配置不合理、司法能动与克制的标准不明、责任承担方式各异等问题;指出环境司法下的蓝碳治理守正创新,须归纳其表层现象、挖掘深层逻辑,从正面肯定蓝碳司法本土化的制度创新,将积累的实践经验上升为理论模型,以环境司法能动回应蓝碳治理,保障审前有限能动、审中适度能动和审后积极能动,以免具有生命力的司法经验在司法改革中被悄无声息地抹除,以蓝碳司法能动与国际社会共谋生态文明之道。 展开更多
关键词 蓝碳 “双碳”目标 司法能动 环境司法
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“双碳”目标下企业环境合规法律问题分析
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作者 潘晓滨 范庆哲 《天津法学》 2024年第1期69-76,共8页
企业合规是避免企业违法犯罪的重要手段,也是企业自身规避经营风险,实现可持续发展的重要方式。为应对当前生态环境保护、应对气候变化的新形势,有必要明确推进企业环境合规制度发展的重要价值。首先完善相关法律规范体系,明确以“立法... 企业合规是避免企业违法犯罪的重要手段,也是企业自身规避经营风险,实现可持续发展的重要方式。为应对当前生态环境保护、应对气候变化的新形势,有必要明确推进企业环境合规制度发展的重要价值。首先完善相关法律规范体系,明确以“立法论”路径将“双碳”目标融入刑法规制相对于“解释论”的优势与合理性。抓住刑事合规这一关键环节,推进事前合规的应用,优化对企业责任人员从宽的适用路径。进一步构建企业环境合规制度体系,促进刑事合规、行政合规等共同发展,借鉴合规援助制度等制度经验助力更大范围内合规建设的开展,充分发挥企业环境合规的制度价值与作用。 展开更多
关键词 “双碳”目标 企业环境合规 立法论 合规援助制度
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Environmental accounting: Theoretical review and research prospects
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作者 ZHANG Shan XU Su-bo 《Ecological Economy》 2018年第2期147-160,共14页
This paper is based on the ecological and harmonious development concept of ecological civilization, and combines economic development, environmental governance and accounting research as the basis for the development... This paper is based on the ecological and harmonious development concept of ecological civilization, and combines economic development, environmental governance and accounting research as the basis for the development of environmental accounting theory. In order to analyze the relevant theories of environmental accounting development at home and abroad, we use the historical measurement research and hierarchical division methods to systematiccally review the theoretical literatures and research progress. It is concluded that:(1) The development of foreign environmental accounting focuses on the formulation of industry norms, the interpretation of regulations and policies, and the organization of the overall structural framework. Relevant environmental costs, environmental accounting, uncertainties and environmental accounting information disclosure throughout the study of Western environmental accounting. The theory is applied to practice and tested in the free market.(2) Domestic related research is mostly based on comprehensive considerations. It started late. Although the overall environmental accounting framework is basically formed and related laws and regulations are gradually improved, there are still some: the environmental accounting subsystem is not clear, and the accounting standards are not unified. Through the combing of domestic and international environmental accounting theories and combining with China's actual national conditions, this paper proposes that in the field of environmental accounting, China needs to further improve relevant legal norms, improve the environmental accounting theory system, clarify the field of environmental accounting research, and determine environmental accounting requirements and methods. 展开更多
关键词 environmental accounting theoretical review framework system target outlook
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Water resources optimization and eco-environmental protection in Qaidam Basin
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作者 FANG Chuang-lin~1, BAO Chao~2 (1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China 2. Dept. of Geography, Peking University, Beijing 100871, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第2期231-238,共8页
In order to realize sustainable development of the arid area of Northwest China, rational water resources exploitation and optimization are primary prerequisites. Based on the essential principle of sustainable develo... In order to realize sustainable development of the arid area of Northwest China, rational water resources exploitation and optimization are primary prerequisites. Based on the essential principle of sustainable development, this paper puts forward a general idea on water resources optimization and eco-environmental protection in Qaidam Basin, and identifies the competitive multiple targets of water resources optimization. By some qualitative methods such as Input-output Model & AHP Model and some quantitative methods such as System Dynamics Model & Produce Function Model, some standard plans of water resources optimization come into being. According to the Multiple Targets Decision by the Closest Value Model, the best plan of water resources optimization, eco-environmental protection and sustainable development in Qaidam Basin is finally decided. 展开更多
关键词 water resources optimization Multiple targets Decision by the Closest Value Model eco-environmental protection Qaidam Basin
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地方政府环境治理目标约束能否提升企业ESG质量?——基于文本分析法的经验证据 被引量:3
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作者 徐妍 宋怡瑾 沈悦 《中国人口·资源与环境》 CSSCI CSCD 北大核心 2024年第3期137-150,共14页
全面实现地区高质量发展对地方政府的环境治理工作提出了更高的标准。作为推动该发展过程的核心主体,企业如何实施环保减排措施、承担社会责任并提升治理水平已成为地区发展的关键因素。该研究整理了2010—2020年中国275个地级市的政府... 全面实现地区高质量发展对地方政府的环境治理工作提出了更高的标准。作为推动该发展过程的核心主体,企业如何实施环保减排措施、承担社会责任并提升治理水平已成为地区发展的关键因素。该研究整理了2010—2020年中国275个地级市的政府年度工作报告,通过文本挖掘方法构建了地方政府环境治理目标的约束性指标,并明确了“规则导向”和“原则导向”两种不同类型的环境治理目标约束。实证分析发现:与原则导向相比,规则导向的环境治理目标约束更有效地提升了区域内企业的ESG质量,且这一结果在更换解释变量和被解释变量、安慰剂检验、工具变量法、倾向得分匹配、外生事件冲击等一系列稳健性检验后依旧稳健。政府绿色补助、公众环境关注、企业信息披露质量、社会责任承担和绿色技术创新能力,都是规则导向的地方政府环境治理目标约束提高企业ESG质量的重要机制。表明区域内企业提升ESG质量的过程,需要政府、公众和企业三方的共同努力和使能。进一步研究发现,在市场化程度高的地区、国有企业,以及高度响应政策的企业中,规则导向的环境治理目标约束表现出更为显著的效果。特别是在环境(E)、社会(S)和治理(G)三个方面,规则导向的治理都有着显著的促进作用,其中在环境方面尤为突出。这为实现减污降碳与可持续发展提供经验证据。 展开更多
关键词 环境治理目标约束 ESG质量 政府行为 公众环境关注
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环境目标约束对能源结构低碳转型的影响 被引量:5
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作者 方文君 邓峰 +1 位作者 张战仁 朱雪丽 《中国人口·资源与环境》 CSSCI CSCD 北大核心 2024年第1期84-96,共13页
加快能源消费结构低碳转型是实现中国式现代化发展的重要途径。鉴于中国资源禀赋的特殊性和区域能源分布差异,各地区对煤炭的依赖程度有很大差别。煤炭资源依赖程度对能源结构低碳转型的差异性影响值得高度关注。为系统评估环境目标约... 加快能源消费结构低碳转型是实现中国式现代化发展的重要途径。鉴于中国资源禀赋的特殊性和区域能源分布差异,各地区对煤炭的依赖程度有很大差别。煤炭资源依赖程度对能源结构低碳转型的差异性影响值得高度关注。为系统评估环境目标约束对煤炭资源依赖地区能源消费结构低碳转型的影响,该研究在理论分析环境目标约束对各地区能源消费结构的内在影响机理,以及经济增长压力和绿色金融在其中发挥的调节作用基础上,以中国特色环境目标约束制度为准自然实验,中国30个省份2003—2020年面板数据为样本,采用广义双重差分模型实证检验环境目标约束对地区能源消费结构低碳转型的影响,并讨论了经济增长压力与绿色金融对该影响的调节作用。研究结果表明:①环境目标约束制度实施后,相比非煤炭资源依赖地区,煤炭资源依赖地区能源消费结构低碳转型受阻,说明存在“绿色悖论”效应。该结论在考虑相关政策影响、运用合成工具变量等方法处理内生性问题后依然稳健。②影响机制检验表明,在煤炭资源依赖地区,地方政府在环境目标约束和经济增长目标“双目标”压力下,更有动力推动能源消费结构低碳转型;受金融监管水平和企业“洗绿”行为影响,绿色金融加剧了煤炭资源依赖地区的能源转型困境。③基于地区市场环境的拓展性分析表明,相比高市场化水平地区,低市场化水平地区的环境目标约束对能源消费结构低碳转型的抑制作用更为突出。研究建议高度重视煤炭资源依赖地区的能源消费结构调整,因地制宜有序推进能源结构低碳转型;将“绿色”作为地方经济增长的底色,以绿色发展理念引领地方经济增长;构建科学高效的绿色金融监管制度,确保绿色金融资金真正运用到绿色低碳项目中;完善市场化的环境规制机制,塑造良好的营商环境。 展开更多
关键词 环境目标约束 能源消费结构 煤炭资源地区 经济增长压力 绿色金融 低碳转型
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Axon regeneration induced by environmental enrichment-epigenetic mechanisms 被引量:1
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作者 Bor Luen Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第1期10-15,共6页
Environmental enrichment is known to be beneficial for cognitive improvement.In many animal models of neurological disorders and brain injury,EE has also demonstrated neuroprotective benefits in neurodegenerative dise... Environmental enrichment is known to be beneficial for cognitive improvement.In many animal models of neurological disorders and brain injury,EE has also demonstrated neuroprotective benefits in neurodegenerative diseases and in improving recovery after stroke or traumatic brain injury.The exact underlying mechanism for these phenomena has been unclear.Recent findings have now indicated that neuronal activity elicited by environmental enrichment induces Ca2+influx in dorsal root ganglion neurons results in lasting enhancement of CREB-binding protein-mediated histone acetylation.This,in turn,increases the expression of pro-regeneration genes and promotes axonal regeneration.This mechanism associated with neuronal activity elicited by environmental enrichment-mediated pathway is one of several epigenetic mechanisms which modulate axon regeneration upon injury that has recently come to light.The other prominent mechanisms,albeit not yet directly associated with environmental enrichment,include DNA methylation/demethylation and N6-methyladenosine modification of transcripts.In this brief review,I highlight recent work that has shed light on the epigenetic basis of environmental enrichment-based axon regeneration,and discuss the mechanism and pathways involved.I further speculate on the implications of the findings,in conjunction with the other epigenetic mechanisms,that could be harness to promote axon regeneration upon injury. 展开更多
关键词 AXON regeneration CREB-binding protein DNA methylation/demethylation dorsal root GANGLION DRG neurons environmental enrichment epigenetics histone acetylation mechanistic target of rapamycin mTOR PHOSPHATASE and TENSIN HOMOLOGUE PTEN
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企业绿色创新的数字逻辑——机制识别与地方政府多目标治理下的效应差异
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作者 韩洁 刘涛 《产业经济研究》 CSSCI 北大核心 2024年第4期58-71,共14页
在数字经济时代,企业绿色创新仍处于压力叠加、负重前行的关键期,探讨企业与政府合力发挥数字技术力量的内在驱动力显得尤为重要。以2011-2021年中国A股上市公司为样本,分析地方政府多目标治理下数字化转型对企业绿色创新的驱动效应。... 在数字经济时代,企业绿色创新仍处于压力叠加、负重前行的关键期,探讨企业与政府合力发挥数字技术力量的内在驱动力显得尤为重要。以2011-2021年中国A股上市公司为样本,分析地方政府多目标治理下数字化转型对企业绿色创新的驱动效应。研究发现,数字化转型显著促进了企业绿色创新,对于大规模、属于重污染行业以及位于高知识产权保护力度地区的企业而言,其产生的驱动效应更加显著。机制分析表明,数字化转型能够通过“靶向优化”效应优化企业人才结构和管理成本,并且能够发挥“缺项补足”效应,缓释企业融资约束和信息不对称,这些都将显著提升企业绿色创新水平。更为重要的是,在数字化转型促进企业绿色创新作用中,地方政府经济增长目标和环境约束目标分别具有负向和正向调节效应,且两者存在协同调节效应,而研发创新目标尚未起到调节作用。研究结果拓展了对企业与政府互动促进数字化转型价值实现路径的分析,为实现数字技术良性发展、政府目标治理模式改善和微观主体绿色创新增效的政策取向提供了经验证据。 展开更多
关键词 绿色创新 数字化转型 经济增长目标 环境约束目标 研发创新目标
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低温靶向再生活化剂与废橡胶再生胶性能的构效关系研究
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作者 王艳秋 张明 +2 位作者 李杰 卢猛 李晓娟 《化工新型材料》 CAS CSCD 北大核心 2024年第11期258-263,共6页
为了实现废橡胶节能减排高品质再生,提出了低温靶向再生活化剂的设计理念,将含有-SH、-OH或-COOH的主再生活化剂(MS)与含有-OH或-COOH的次再生活化剂(有机酸A1)并用,在再生温度25~125℃下开展研究。结果表明:MS/A1具有协同效应,低温靶... 为了实现废橡胶节能减排高品质再生,提出了低温靶向再生活化剂的设计理念,将含有-SH、-OH或-COOH的主再生活化剂(MS)与含有-OH或-COOH的次再生活化剂(有机酸A1)并用,在再生温度25~125℃下开展研究。结果表明:MS/A1具有协同效应,低温靶向再生胶拉伸强度和扯断伸长率分别达15.17MPa、360.65%,门尼黏度为79,达到了《再生橡胶通用规范》(GB/T 13460-2016)全胎胶粉优质品级R-T再生胶的性能要求,再生胶所含18项多环芳烃总含量小于20mg/kg,符合欧盟REACH法规(REACH-2009/48/EC)环保指标的要求。与高温再生工艺相比,低温靶向再生工艺节能20%~60%不等。 展开更多
关键词 低温靶向再生活化剂 物理机械性能 工艺性能 环保性能 构效关系
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遮挡环境下基于航海雷达的舰船目标跟踪方法研究
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作者 孙帅 吕红光 黄骁 《中国舰船研究》 CSCD 北大核心 2024年第1期55-61,共7页
[目的]针对无人艇平台航海雷达在舰船目标跟踪中因障碍物遮挡而造成的目标航迹断裂问题,需综合利用环境先验信息,以提高雷达探测受限时目标跟踪航迹的连续性。[方法]通过提出遮挡环境下的综合概率数据互联(IPDA)算法,即O-IPDA,对环境遮... [目的]针对无人艇平台航海雷达在舰船目标跟踪中因障碍物遮挡而造成的目标航迹断裂问题,需综合利用环境先验信息,以提高雷达探测受限时目标跟踪航迹的连续性。[方法]通过提出遮挡环境下的综合概率数据互联(IPDA)算法,即O-IPDA,对环境遮挡情况进行实时预判;在遮挡环境中通过采用低检测概率和针对性设计的存在状态概率转移矩阵,以维持目标跟踪的连续性。[结果]在单目标跟踪场景中,当目标被暂时遮挡时,O-IPDA可以避免目标因持续性漏检而丢失,以保持跟踪航迹的稳定性,其中算法的抗遮挡能力取决于O-IPDA存在状态概率转移矩阵中的相关参数设置。[结论]O-IPDA目标跟踪方法具有一定的抗遮挡能力,可为航海雷达单目标跟踪研究提供参考。 展开更多
关键词 目标检测与跟踪 目标遮挡 环境先验信息 综合概率数据互联(IPDA)
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经济增长目标管理对城市土地绿色利用效率的影响——基于282个地级及以上城市的经验证据 被引量:2
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作者 边志强 《中国土地科学》 CSSCI CSCD 北大核心 2024年第4期54-64,共11页
研究目的:利用2006—2021年全国282个地级及以上城市的面板数据,系统考察经济增长目标管理对城市土地绿色利用效率的影响。研究方法:超效率SBM模型,固定效应模型。研究结果:(1)经济增长目标对城市土地绿色利用效率呈现明显的负向影响效... 研究目的:利用2006—2021年全国282个地级及以上城市的面板数据,系统考察经济增长目标管理对城市土地绿色利用效率的影响。研究方法:超效率SBM模型,固定效应模型。研究结果:(1)经济增长目标对城市土地绿色利用效率呈现明显的负向影响效应,且这一结论通过了克服内生性等一系列稳健性检验。(2)正式与非正式环境规制均能够减缓经济增长目标对城市土地绿色利用效率的负向影响,且后者的调节效应更强。(3)经济增长目标存在明显的自上而下逐级加码现象,且目标加码行为会对城市土地绿色利用效率产生抑制作用。(4)当目标约束程度为一般约束和硬约束,以及目标完成情况从未完成、正常完成到超额完成时,经济增长目标对城市土地绿色利用效率的负向影响显著且逐渐增强。研究结论:进一步淡化GDP增速在官员绩效考核中的重要性,尽量采用“留有余地”的软约束方式设定经济增长目标,重视环境规制的约束作用。 展开更多
关键词 经济增长目标管理 城市土地绿色利用效率 环境规制 目标加码 目标约束
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农药信息学方法在线平台及其农药研发中应用
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作者 陈东雨 梅龙灿 +2 位作者 王玮 郝格非 杨光富 《世界农药》 CAS 2024年第6期1-8,15,共9页
绿色农药是防治病、虫、草等有害生物,保障粮食安全的重要“武器”。农药信息学已成功应用于农药靶标识别、活性成分设计和环境影响评价等农药研究与开发各个阶段。通过系统性整合农药信息学相关的工具、方法等,搭建了一站式在线平台(ht... 绿色农药是防治病、虫、草等有害生物,保障粮食安全的重要“武器”。农药信息学已成功应用于农药靶标识别、活性成分设计和环境影响评价等农药研究与开发各个阶段。通过系统性整合农药信息学相关的工具、方法等,搭建了一站式在线平台(http://chemyang.ccnu.edu.cn/ccb/database/PIP/),并在此基础上,介绍了其在农药研发中的应用,探讨了农药抗性管理和环境风险评估等农药信息学未来研究方向。旨在充分发挥农药信息学方法及一站式在线平台在农药研发中的作用,指导、助力绿色新农药创制。 展开更多
关键词 农药信息学 农药研究与开发 靶标识别 活性成分设计 环境影响评估
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高校美育的价值逻辑、现实难点与实践路径
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作者 麻凯阳 《教育理论与实践》 北大核心 2024年第18期20-22,共3页
美育在人格塑造、陶冶情操、素质教育等方面都发挥着关键作用。从“五育并举”到“五育融合”是贯彻落实新时代党的教育方针和有关政策的需要。高校美育作为五育的一项重要内容,面临着重构与改革,完善高校美育体系是高校实现基本功能的... 美育在人格塑造、陶冶情操、素质教育等方面都发挥着关键作用。从“五育并举”到“五育融合”是贯彻落实新时代党的教育方针和有关政策的需要。高校美育作为五育的一项重要内容,面临着重构与改革,完善高校美育体系是高校实现基本功能的重要途径,是个人实现全面发展的重要手段,是联系德智体劳的关键桥梁。然而,当前部分高校存在许多现实难点,需要通过进一步明确高校美育的目标定位,进一步完善高校美育的环境氛围,进一步健全高校美育的评价机制,才能形成全覆盖、多样化、高质量的具有中国特色的现代化学校美育体系。 展开更多
关键词 高校美育 目标定位 环境氛围 评价机制
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海上搜救打捞装备发展研究
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作者 弓永军 孙玉清 +2 位作者 李华军 董传明 张增猛 《中国工程科学》 CSCD 北大核心 2024年第2期50-62,共13页
搜救打捞是海上安全的最后一道防线,为国家综合运输体系建设、海洋经济可持续发展提供可靠保障;搜救打捞装备是履行海上人员安全、环境安全、财产救助、应急抢险打捞等公益性职责,保障国家海上物流供应链安全的重要支撑。本文从目标搜... 搜救打捞是海上安全的最后一道防线,为国家综合运输体系建设、海洋经济可持续发展提供可靠保障;搜救打捞装备是履行海上人员安全、环境安全、财产救助、应急抢险打捞等公益性职责,保障国家海上物流供应链安全的重要支撑。本文从目标搜寻定位与探测装备、海上人命救助装备、海上环境救助装备、打捞工程专用装备四方面着手,全面梳理了国外海上搜救打捞装备的发展现状,以及我国海上搜救打捞装备的研制与应用进展。与国外发达国家相比,我国海上搜救打捞装备发展存在搜寻定位装备落后、海上人命救助能力不强、危化品处置能力较低、大吨位沉船打捞能力薄弱等问题。在进一步辨识海上搜救打捞装备发展前沿的基础上,提出了加大关键装备的研发投入、推动搜救打捞装备的升级迭代、强化科技创新能力以提升装备智能化水平、部署搜救打捞技术装备攻关工程、提供相应产业政策支持等建议,以期促进我国海上搜救打捞装备高质量发展。 展开更多
关键词 搜救打捞 搜寻定位 人命救助 环境救助 升沉补偿技术
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基于强化学习的多飞行器目标分配方法
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作者 刘华华 王青 《空天防御》 2024年第5期65-72,共8页
针对复杂环境下多飞行器对多目标分配问题,本文提出了一种基于强化学习的多飞行器目标分配方法。首先,建立飞行器执行任务的战场环境模型,获取飞行器作战能力信息以及环境信息,并加以量化;其次,利用强化学习算法,进行多组飞行器作战目... 针对复杂环境下多飞行器对多目标分配问题,本文提出了一种基于强化学习的多飞行器目标分配方法。首先,建立飞行器执行任务的战场环境模型,获取飞行器作战能力信息以及环境信息,并加以量化;其次,利用强化学习算法,进行多组飞行器作战目标分配;最后,考虑飞行器出现损毁情况,进行目标动态重分配决策,以提高在战场突发情况下的任务完成度。仿真结果表明了该算法的有效性。 展开更多
关键词 多飞行器 目标分配 强化学习 环境不确定性
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