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Accuracy allocation method for five-axis machine tools based on geometric error cost sensitivity prioritizing tool direction deviation 被引量:1
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作者 Xiaojian LIU Ao JIAO +7 位作者 Yang WANG Guodong YI Xiangyu GAO Xiaochen ZHANG Yiming ZHANG Yangjian JI Shuyou ZHANG Jianrong TAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第7期635-651,共17页
Accuracy allocation is crucial in the accuracy design of machining tools.Current accuracy allocation methods primarily focus on positional deviation,with little consideration for tool direction deviation.To address th... Accuracy allocation is crucial in the accuracy design of machining tools.Current accuracy allocation methods primarily focus on positional deviation,with little consideration for tool direction deviation.To address this issue,we propose a geometric error cost sensitivity-based accuracy allocation method for five-axis machine tools.A geometric error model consisting of 4l error components is constructed based on homogeneous transformation matrices.Volumetric points with positional and tool direction deviations are randomly sampled to evaluate the accuracy of the machine tool.The sensitivity of each error component at these sampling points is analyzed using the Sobol method.To balance the needs of geometric precision and manufacturing cost,a geometric error cost sensitivity function is developed to estimate the required cost.By allocating error components affecting tool direction deviation first and the remaining components second,this allocation scheme ensures that both deviations meet the requirements.We also perform numerical simulation of a BC-type(B-axis and C-axis type)five-axis machine tool to validate the method.The results show that the new allocation scheme reduces the total geometric error cost by 27.8%compared to a uniform allocation scheme,and yields the same positional and tool direction machining accuracies. 展开更多
关键词 Five-axis machine tool Accuracy allocation Geometric error modeling Error cost sensitivity Tool direction deviation priority
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Conservation Priorities for Lizard Biodiversity in the Qinghai-Xizang Plateau Under Climate Change:Current Status and Future Strategies
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作者 Tong LIU Xiaolong ZHAO +3 位作者 Jinyan YANG Yiqiong CUI Min CHEN Zhigao ZENG 《Asian Herpetological Research》 2025年第2期210-226,共17页
Global framework for nature management requires identifying areas of high priority for biodiversity conservation and restoration.The unique environments of Qinghai-Xizang Plateau(QXP) provide irreplaceable habitats fo... Global framework for nature management requires identifying areas of high priority for biodiversity conservation and restoration.The unique environments of Qinghai-Xizang Plateau(QXP) provide irreplaceable habitats for biodiversity which is prominent under future climate change.Despite the recent increase in research interest on conservation priorities,there is a lack of comprehensive and targeted protection strategies for pandemic species under climate change.Here,we compiled an exhaustive dataset with the variables of extinction risk and occurrence records of ectothermic lizards to investigate the conservation priorities in the QXP.We assessed the conservation status of the QXP lizards and identified the priority protected areas within the QXP under future climate scenarios using phylogenetic generalized least squares and ensemble species distribution models.Our analyses suggested nine lizard species to be prioritized for protection,with the most critical priority species being Dopasia gracilis,D.harti,and Phrynocephalus putjatai.Moreover,the priority protected areas covered~4.7%area of the QXP,mostly in the southern QXP and southeastern Hengduan Mountains.Protecting these regions would achieve a conservation effectiveness of≥95%for species richness,phylogenetic and functionaldiversity under climate change.Our findings provide realistic guidance for improving the conservation effectiveness of specific-lizard and-regions in the QXP under climate change.Our“bottom-up”approach could help the conservation efforts of other regions and species as an alternative to“top-down”global maps. 展开更多
关键词 climate change conservation priorities LIZARDS multidimensional biodiversity Qinghai-Xizang Plateau
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Integrated spatial priority assessment in Central Asia:Bridging biodiversity,ecosystem services,and human activities
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作者 Shiran Song Xi Chen +4 位作者 Chanjuan Zan Hao Zhang Chuan Wang Zengyun Hu Yaoming Li 《Geography and Sustainability》 2025年第2期194-208,共15页
Central Asia(CA)faces escalating threats from increasing temperature,glacier retreat,biodiversity loss,unsustainable water use,terminal lake shrinkage,and soil salinization,all of which challenge the balance between e... Central Asia(CA)faces escalating threats from increasing temperature,glacier retreat,biodiversity loss,unsustainable water use,terminal lake shrinkage,and soil salinization,all of which challenge the balance between ecological integrity and socio-economic development essential for achieving Sustainable Development Goals.However,a comprehensive understanding of priority areas from a multi-dimensional perspective is lacking,hindering effective conservation and development strategies.To address this,we developed a comprehensive assessment framework with a tailored indicator system,enabling a spatial evaluation of CA’s priority areas by integrating biodiversity,ecosystem services(ESs),and human activities.Combining zonation and geographical detectors,this approach facilitates spatial prioritization and examines ecological and socio-economic heterogeneity.Our findings reveal a heterogeneous distribution of priority areas across CA,with significant concentrations in eastern mountainous regions,river valleys,and oasis agricultural lands.We identified 184 key districts crucial for ecological and societal sustainability.Attribution analysis shows that natural factors like soil types,precipitation,and evapotranspiration significantly shape these areas,influencing human activities and the distribution of biodiversity and ESs.Multi-dimensional analysis indicates existing protected areas cover only 15%of the top 30%priority areas,revealing substantial conservation gaps.Additionally,a 38%overlap between ESs and human activities,along with 63.25%congruence in integrated areas,underscores significant human impacts on ecological systems and their dependency on ESs.Given CA’s limited resources,it is crucial to implement measures that strengthen conservation efforts,align ecological preservation with socio-economic demands,and enhance resource efficiency through sustainable integrated land and water resource management. 展开更多
关键词 Spatially priority assessment BIODIVERSITY Ecosystem services Human activities Central Asia
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Post-pandemic mental health:Understanding the global psychological burden and charting future research priorities
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作者 Wei Ding Yuan Zhang +1 位作者 Min-Zhong Wang Shu Wang 《World Journal of Psychiatry》 2025年第10期67-86,共20页
The coronavirus disease 2019 pandemic has left an indelible mark on global mental health,with widespread psychological consequences that persist beyond the acute phase of the virus.This review synthesizes current evid... The coronavirus disease 2019 pandemic has left an indelible mark on global mental health,with widespread psychological consequences that persist beyond the acute phase of the virus.This review synthesizes current evidence on the postpandemic mental health burden across diverse populations,highlighting elevated rates of depression,anxiety,posttraumatic stress,and substance use disorders linked to prolonged social isolation,economic instability,and grief.We examine disparities in psychological outcomes among vulnerable groups(e.g.,healthcare workers,survivors,marginalized communities)and identify key challenges in addressing these issues,including fragmented healthcare systems,stigma,and the limited scalability of interventions.Emerging evidence on resilience factors(e.g.,social support and adaptive coping)is also discussed.Finally,we propose critical priorities for future research,including longitudinal studies on the chronic mental health effects,the development of culturally tailored interventions,and the integration of digital mental health solutions.This review distinctively addresses enduring post-pandemic mental health challenges,integrating neurobiological insights,equity-focused interventions,and critical perspectives on digital solutions,gaps underrepresented in prior syntheses.By charting a roadmap for multidisciplinary collaboration,this review aims to inform policymakers and researchers in mitigating the long-term psychological aftermath of the pandemic. 展开更多
关键词 COVID-19 Mental health Psychological burden Postpandemic Research priorities Global health
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A framework of the planning of priority revegetation areas for debris flow mitigation based on microclimate processes in dry-hot watersheds
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作者 LU Yafeng ZHOU Xiaokang 《Journal of Mountain Science》 2025年第5期1723-1733,共11页
Vegetation restoration is a critical strategy for mitigating debris flow hazards by stabilizing slopes and modifying hydrological processes.Effective planning of priority restoration areas is particularly essential in... Vegetation restoration is a critical strategy for mitigating debris flow hazards by stabilizing slopes and modifying hydrological processes.Effective planning of priority restoration areas is particularly essential in dry-hot valley regions,where extreme hydrothermal conditions pose significant challenges.This study presents a novel framework that integrates microclimatic variables,such as temperature lapse rates,to enhance the spatial precision of revegetation efforts.The Reshuihe watershed in Southwest China,a representative dry-hot valley,was chosen as the study area.By analyzing hourly temperature and rainfall across an elevation gradient,a quadratic relationship between temperature lapse rates and weak rainfall events was identified,underscoring the role of microclimatic processes in influencing rainfall distribution and plant-available water.Rainfall peaks were observed when the temperature lapse rate was approximately 4.5°C/km.This relationship was incorporated into a cost-based restoration framework using the Marxan model,optimizing the spatial allocation of priority areas for revegetation.Results demonstrated that integrating microclimatic variables significantly improved the effectiveness of revegetation strategies,particularly for reducing debris flow risks.The lowest restoration costs were observed between elevations of 3200 m and 3300 m,where strong correlations between temperature lapse rates and rainfall were recorded.Priority restoration areas covered 41 km^(2),targeting zones with high debris flow risks.These findings highlight the value of incorporating microclimatic data into revegetation planning,enabling cost-effective and ecologically sustainable hazard mitigation in regions vulnerable to hydrological hazards. 展开更多
关键词 REVEGETATION Microclimate processes Temperature lapse rate Dry-hot valley priority revegetation areas
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Ecological restoration priority on the Qinghai-Xizang Plateau based on the nature’s contributions to people under SDGs-SSPs scenarios
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作者 Hua Liu Shiliang Liu +3 位作者 Fangfang Wang Yifei Zhao Yuhong Dong Lam-Son Phan Tran 《Geography and Sustainability》 2025年第5期101-115,共15页
Ecological restoration is considered an important way to mitigate ecosystem degradation and improve regional nature’s contributions to people(NCPs).Ecological planning is a prerequisite for ecological restoration and... Ecological restoration is considered an important way to mitigate ecosystem degradation and improve regional nature’s contributions to people(NCPs).Ecological planning is a prerequisite for ecological restoration and the prevention of future ecological risks.However,few studies have focused on integrating ecological plans within the framework of Sustainable Development Goals(SDGs)and shared socioeconomic pathways(SSPs).In this study,taking the Qinghai‒Xizang Plateau(QXP)as a case,we assessed ecological restoration priorities based on NCPs under various SDGs and SSP scenarios.Specifically,the land use demand was predicted using system dynamics(SD)and cellular automata(CA)models between 2030 and 2060 under SDG-SSP scenarios.In addition,habitat maintenance(NCP1),climate regulation(NCP4),and water quantity regulation(NCP6)were assessed based on the predicted land use.Finally,priority areas for ecological restoration were identified using a zonation model.The results indicated that the grassland,forest,and cultivated areas will increase in the SDGs and SSPs scenarios,respectively.The high-value NCP areas are mainly located in the southeast part of the QXP,accounting for 45.16%of the study area.In addition,the ecological restoration area involves grassland,cultivated and bare land.In the single-objective scenario,NCP1,NCP4,and NCP6 can be improved by 30.29%,28.75%and 25.63%,respectively,through the restoration of 15.33%of the priority areas identified in 2015.When shifting to a multi-objective cooperative optimum,NCP1,NCP4 and NCP6 can be improved 35.79%by restoring 54.96%of the priority areas.This study provides insight into how SDGs and SSPs can contribute to ecological restoration for mitigating ecosystem degradation under SDG-SSP scenarios. 展开更多
关键词 System dynamics Cellular automata Sustainable developmentgoals Nature’s contributionton people Shared socioeconomic pathways priority area
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What’s in a name for timber?Trade documentation and conservation prioritization in four tropical timber species imported to the United States
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作者 Mandira POKHAREL René Henri GERMAIN +2 位作者 John Eric WAGNER Susan Elizabeth ANAGNOST William Bradford SMITH 《Regional Sustainability》 2025年第5期1-18,共18页
The tropical timber trade faces significant sustainability challenges,including deforestation,illegal logging,and inadequate traceability.Inaccurate species identification further complicates these issues,leading to u... The tropical timber trade faces significant sustainability challenges,including deforestation,illegal logging,and inadequate traceability.Inaccurate species identification further complicates these issues,leading to unreliable trade statistics and enforcement challenges.The Lacey Act Amendment(LAA)of 2008 mandated declaring scientific names for timber shipments entering the United States.Therefore,this study assessed the implementation of the LAA using data obtained through a Freedom of Information Act request to the United States Department of Agriculture-Animal and Plant Health Inspection Service for 4 tropical timber species including Keruing,Meranti,Acajou d’Afrique,and Mahogany from Indonesia,Malaysia,Brazil,Philippines,Cameroon,Ghana,Congo,Cote d’Ivoire,and Bolivia,with high rates of illegal logging.This study showed that the United States imported 49 species of Keruing species group,126 species of Meranti species group,6 species of Acajou d’Afrique species group,and 2 species of Mahogany species group during 2017-2023.Despite mandatory declarations,approximately 14.60%of timber import records lacked species-specific names.Conservation assessments identified 37 species of Keruing species group and 68 species of Meranti species group listed as threatened by the International Union for Conservation of Nature(IUCN)but absent from the Convention on International Trade in Endangered Species of Wild Fauna and Flora(CITES).Moreover,the principal component analysis(PCA)indicated that the first principal component was primarily driven by import value and import volume,reflecting the overall trade prominence,while the second principal component captured temporal pattern through import year.Further,this study developed a Trade-Adjusted Conservation Priority Index(TACPI)that integrated conservation status with trade prominence to prioritize species at risk.Species with high TACPI scores,such as Dipterocarpus coriaceus and Shorea balangeran,were identified as urgently needing regulatory focus.To strengthen sustainable trade and conservation,it is recommended to enforce the LAA more strictly,expand timber identification technologies,and mandate key supplier countries,who are the CITES’signatories,to list high-risk species in the CITES appendices. 展开更多
关键词 Tropical timber trade Principal component analysis(PCA) Trade-Adjusted Conservation priority Index(TACPI) International Union for Conservation of Nature(IUCN) Convention on International Trade in Endangered Species of Wild Fauna and Flora(CITES)
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“十五五”背景下职业教育的认知重构与行动逻辑
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作者 姜大源 《中国职业技术教育》 北大核心 2026年第2期5-9,26,共6页
《关于制定国民经济和社会发展第十五个五年规划的建议》有三个值得职业教育充分关注的战略要点,即实体经济、技能人才、就业优先。这三个关键词正是新时代职业教育的发展方向。为此,职业教育要有所作为,就必须进行认知重构,采取行之有... 《关于制定国民经济和社会发展第十五个五年规划的建议》有三个值得职业教育充分关注的战略要点,即实体经济、技能人才、就业优先。这三个关键词正是新时代职业教育的发展方向。为此,职业教育要有所作为,就必须进行认知重构,采取行之有效的行动:一要为巩固壮大实体经济根基助力,二要为培养造就战略技能人才发力,三要为深入实施就业优先战略聚力,以不辱历史赋予职业教育的光荣使命。 展开更多
关键词 “十五五”规划 职业教育 实体经济 技能人才 就业优先
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远程医疗技术与医疗优先分级调派系统整合的效果评估:一项基于318名医疗相关人员调查的中期分析
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作者 梁永利 张培 胡翼南 《医学研究前沿》 2026年第1期136-138,共3页
目的基于318名医疗相关人员调查中期分析结果评估整合远程医疗技术与医疗优先分级调派系统(MPDS)的应用效果。方法本次研究对象为318名医疗人员及患者家属,采用自制调查问卷进行调查,分析研究对象对MPDS、远程医疗技术的认知情况、满意... 目的基于318名医疗相关人员调查中期分析结果评估整合远程医疗技术与医疗优先分级调派系统(MPDS)的应用效果。方法本次研究对象为318名医疗人员及患者家属,采用自制调查问卷进行调查,分析研究对象对MPDS、远程医疗技术的认知情况、满意度以及MPDS与远程医疗技术的整合预期。结果研究对象对MPDS总体认知度较高(61.95%),使用过MPDS的研究对象占比相对较低(43.08%)。大部分应用过MPDS的研究对象认为MPDS能够发挥积极作用且满意度较高。医疗相关人员及患者家属对远程医疗技术的认知度(61.64%)、接受度(91.19%)较高,绝大部分的研究对象认为整合远程医疗技术与MPDS能够提升急救效率(91.82%)。研究对象最为认可的预期优势为可视化指导更精准,构成比显著高于其他预期优势指标(P<0.05),其他各项预期优势指标构成比差异不具有统计学意义(P>0.05)。研究对象最为集中的期待功能为一键视频连通指导,构成比高于其他期待功能指标且差异具有统计学意义(P<0.05),其他各项期待功能构成比差异均具有统计学意义(P<0.05)。结论通过中期分析结果可知,MPDS与远程医疗技术系统整合受众基础广泛且有着较高的认可度与满意度。整合方案需要以提高操作简便性、保证技术普及型包以及实现核心功能为重点,从而能够有效应对复杂情况下患者信息不足的问题,可提高急救效率。 展开更多
关键词 远程医疗技术 医疗优先分级调派系统 急救效率 整合效果
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“十四五”我国节能提效成效研判与“十五五”展望
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作者 魏一鸣 李慧 廖华 《中国环境管理》 2026年第1期15-23,共9页
节能提效是推进生态文明建设、促进经济社会发展全面绿色转型的重要举措。本文回顾了“十四五”时期我国各地区及重点领域节能进展,并总结了取得的主要成效;结合国内外形势及国家中长期战略规划,从节能长期战略定位、覆盖范围、实施路... 节能提效是推进生态文明建设、促进经济社会发展全面绿色转型的重要举措。本文回顾了“十四五”时期我国各地区及重点领域节能进展,并总结了取得的主要成效;结合国内外形势及国家中长期战略规划,从节能长期战略定位、覆盖范围、实施路径等方面分析了“十五五”及中长期我国节能形势。提出“十五五”时期我国节能需要关注的重点方向,包括全面推进能耗双控向碳排放双控转型,加速重点领域节能提效,推进能源产业链节能提效与系统优化,以及提升数据中心、算力网络等新型基础设施建设能效。本文建议从健全经济激励政策和管理体制、持续深化需求侧改革、建立统计监测与预警体系、强化基础能力建设四方面统筹节能工作,以保障节能目标顺利实现并支撑能源强国建设。 展开更多
关键词 能源经济 节能提效 节能潜力 重点任务 “十五五”时期
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VVER-1200核电站安全级执行器驱动指令优先级研究
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作者 夏利民 王潇 +1 位作者 白玮 鲁超 《自动化仪表》 2026年第1期49-54,共6页
安全级执行器作为核电站重要的组成部分,需要在不同工况下执行不同的动作,以实现核电站的安全保护功能和控制功能。在核电站仪控系统设计时,需考虑来自不同的仪控系统/设备的安全级执行器驱动指令优先级方案,以实现安全级执行器的指令... 安全级执行器作为核电站重要的组成部分,需要在不同工况下执行不同的动作,以实现核电站的安全保护功能和控制功能。在核电站仪控系统设计时,需考虑来自不同的仪控系统/设备的安全级执行器驱动指令优先级方案,以实现安全级执行器的指令优先级处理和驱动功能。以水-水高能反应堆(VVER)-1200堆型核电站国产化平台的主仪控系统为基础,介绍了核电站安全级执行器驱动指令优先级设计原则和设计方法。进一步阐述了控制器、优先级设备以及电气开关盘等不同层级的优先级设计要求和目标。提出了适用于VVER-1200的优先级设计方案,并已成功应用于实际工程项目。该方案对于不同堆型核电站优先级控制方案设计和优先级驱动控制系统研发具有重要的借鉴意义。 展开更多
关键词 水-水高能反应堆 核电站 安全级 仪控系统 执行器 驱动指令 优先级
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多元主体视角下街道非机动交通路权研究
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作者 惠英 李伟江 +1 位作者 廖佳妹 郭佳怡 《城市交通》 2026年第1期13-23,共11页
在存量为主的城市发展阶段,落实非机动交通路权优先意味着对街道时空资源的再分配和路权关系的再调整,需统筹协调多元主体之间的复杂权益关系。融合产权、工程与经济社会学等多学科视角,界定了路权的内涵、主体与客体及其相互关系,将具... 在存量为主的城市发展阶段,落实非机动交通路权优先意味着对街道时空资源的再分配和路权关系的再调整,需统筹协调多元主体之间的复杂权益关系。融合产权、工程与经济社会学等多学科视角,界定了路权的内涵、主体与客体及其相互关系,将具体权益划分为过程权力和结果利益,从而构建了多元主体视角下的街道路权概念体系。针对实践中存在的管理权责分散、公众诉求表达不畅、更新动力机制不足等难点,研究归纳出单中心政府主导型、单中心政府引导型、在地机构支持型、多部门协作型4类路权调整模式。围绕空间、经济、文化3个维度构建评估指标体系,通过问卷调查评估了非机动交通视角下不同路权调整模式的效益差异。最后,从推动多元共治、探索适宜实施路径以及完善动力机制3个方面提出对策建议。 展开更多
关键词 非机动交通 路权优先 街道更新 多元主体 效益评估
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一种融合Priority-Flood算法与D8算法特点的河网提取方法 被引量:9
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作者 卢庆辉 熊礼阳 +2 位作者 蒋如乔 巫晓玲 段家朕 《地理与地理信息科学》 CSCD 北大核心 2017年第4期40-46,共7页
基于数字高程模型(Digital Elevation Models)进行河网提取是数字地形分析的重要研究内容和水文分析的关键步骤,而流向算法是其中最重要的部分。然而,传统的流向算法在平坦地形区域容易形成平行河网。为解决平行河网问题,该文提出了一... 基于数字高程模型(Digital Elevation Models)进行河网提取是数字地形分析的重要研究内容和水文分析的关键步骤,而流向算法是其中最重要的部分。然而,传统的流向算法在平坦地形区域容易形成平行河网。为解决平行河网问题,该文提出了一种结合Priority-Flood算法漫水思想和改进D8算法的流向算法。借助Priority-Flood算法的漫水思想,可以保证流向符合宏观地形特征;同时将地形划分为上坡、平地和下坡3种类型,辅以PriorityFlood算法可以实现在不填洼的基础上计算流向,而且针对不同地形,采用相应的改进D8流向算法,从而保证流向符合微观地形特征。通过这两种算法的结合,可以直接使用原始DEM提取河网,消除了填洼过程,提高了流向计算效率,同时消除了填洼造成的大量平地,有效地解决了平地区域平行河网问题。最后,选取全球不同区域SRTM数据对J&D算法与新算法进行对比实验,结果表明,新算法能够有效地改善平行河网问题。 展开更多
关键词 河网提取 priority2Flood算法 D8算法 平行河网 流向算法
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基于功能-要素耦合关系的生态优先保护区识别 被引量:1
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作者 郇轶中 梁涛 +3 位作者 高吉喜 管理 王凌青 周广金 《资源科学》 北大核心 2026年第1期14-26,共13页
【目的】生态优先保护区的识别是国土空间治理决策和实施中的关键环节。然而,目前对生态系统多功能性和复杂耦合关系的理解仍然有限,阻碍了全面有效的生态保护进程。本文基于功能-要素耦合关系,探讨了多目标协同下的生态优先保护区,为... 【目的】生态优先保护区的识别是国土空间治理决策和实施中的关键环节。然而,目前对生态系统多功能性和复杂耦合关系的理解仍然有限,阻碍了全面有效的生态保护进程。本文基于功能-要素耦合关系,探讨了多目标协同下的生态优先保护区,为国土空间规划中的生态治理政策提供支持。【方法】以三门峡市为例,本文采用生态系统服务和权衡的综合评估模型、水量平衡方程、修正的通用土壤流失方程等多种定量模型和空间分析方法,评估了生物多样性、水源涵养、固碳和水土保持4种生态系统功能以及山体、水体和植被3个景观要素的重要性,并揭示了功能-要素的空间耦合关系,从而确定了生态优先保护区。【结果】①虽然4种生态系统功能的重要区域的重叠面积仅36.9 km^(2),但当生态系统功能数量减少为2个或3个时,重叠面积分别增加了14倍或45倍;3个景观要素的重要区域的面积合计为4619.8 km^(2),其中,重叠部分为1242.8 km^(2),占综合景观要素重要区域的面积的36.8%。②综合生态系统功能和景观要素的重要区域分别占三门峡市总面积的29.6%和34.0%,两者间高协同性区域超过75.0%;③生态保护优先级高的区域占全市总面积的41.0%,现有生态保护区面积不足优先保护区域的一半;从代表性、协同性和挑战性3个方面提出了三门峡市生态保护面临的主要挑战和行动建议。【结论】本文提出的生态优先保护区识别框架,不仅耦合了功能-要素的双重视角,还通过多种定量方法的综合运用兼顾精度及适用性,有助于生态保护行动方案的制定与实施。 展开更多
关键词 生态系统功能 景观要素 生态保护 优先级 可持续发展目标 三门峡市
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Priority approach based on quadratic programming model to fuzzy preference relation 被引量:1
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作者 徐泽水 达庆利 陈琦 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期108-110,共3页
We investigate the decision-making problem with a finite set of alternatives,in which the decision information takes the form of a fuzzy preference relation. We develop asimple and practical approach to obtaining the ... We investigate the decision-making problem with a finite set of alternatives,in which the decision information takes the form of a fuzzy preference relation. We develop asimple and practical approach to obtaining the priority vector of a fuzzy preference relation. Theprominent characteristic of the developed approach is that the priority vector can generally beobtained by a simple formula, which is derived from a quadratic programming model. We utilize theconsistency ratio to check the consistency of fuzzy preference relation. If the fuzzy preferencerelation is of unacceptable consistency, then we can return it to the decision maker to reconsiderstructuring a new fuzzy preference relation until the fuzzy preference relation with acceptableconsistency is obtained. We finally illustrate the priority approach by two numerical examples. Thenumerical results show that the developed approach is straightforward, effective, and can easily beperformed on a computer. 展开更多
关键词 decision making fuzzy preference relation quadratic programming priority
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On Application of Nida’s Priorities in Translation 被引量:1
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作者 杨丹宇 《内蒙古师范大学学报(哲学社会科学版)》 2001年第S1期47-49,共3页
This paper analyzes Nida’s theory of translation, also his system of priorities. The paper uses examples to illustrate the application of Nida’s four priorities in the practice of English Chinese and Chinese English... This paper analyzes Nida’s theory of translation, also his system of priorities. The paper uses examples to illustrate the application of Nida’s four priorities in the practice of English Chinese and Chinese English translation and concludes that we can apply the system to help the receptors of second language and source language to have the closest response. 展开更多
关键词 priorities TRANSLATION PRACTICE
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基于互补性的重点保护野生动植物优先保护区识别——以北京怀柔区为例
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作者 朱玥 李果 +8 位作者 赵彩云 高晓奇 罗遵兰 孙光 王平 胡晓生 肖文宏 董文攀 刘浩宇 《生态学报》 北大核心 2026年第4期1892-1902,共11页
国家与地方重点保护野生动植物及其栖息地是生物多样性保护的重要内容。为获取以提升重点保护物种保护率为目标的规划单元组合,构建了一套基于物种组成互补性排序与概率抽样原理的优先保护区判识算法。并在优先保护区筛选过程中,融合物... 国家与地方重点保护野生动植物及其栖息地是生物多样性保护的重要内容。为获取以提升重点保护物种保护率为目标的规划单元组合,构建了一套基于物种组成互补性排序与概率抽样原理的优先保护区判识算法。并在优先保护区筛选过程中,融合物种保护重要级加权处理与栖息地面积保护目标设定,强调了对高保护重要级物种与局限分布物种的栖息地保护。以北京怀柔区为案例区,针对该区域内222种国家/北京市重点保护野生动植物,运用上述算法识别了重点保护物种保护率分别达到80%、95%和100%的优先保护区。这些优先保护区的面积占怀柔区全区面积的比例分别为5.92%、9.10%和10.83%。通过优先保护区与生态保护红线范围的叠加分析,发现怀柔区重点保护物种保护空缺主要分布在雁栖湖与怀柔水库周边区域,以及怀九河上游地带。与基于热点区域的优先保护区识别方法相比,本文方法选取的区域更具代表性和成本效益优势,能有效支撑提升重点保护物种保护率的目标。但本文方法识别的优先保护单元具有离散的空间分布格局,这体现了不同物种在空间分布上的差异性。鉴于此,优先保护单元上的就地保护应同区域生态空间保护紧密结合,在加强重点保护物种关键分布区管护的同时,进一步减缓区域人类活动带来的干扰与保护压力。 展开更多
关键词 重点保护物种 公里网格 互补性排序算法 优先保护区 空间规划
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基于改进LaCAM算法的多机器人路径规划算法
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作者 陈佳鸿 张雷 +2 位作者 邹风山 吕祥仁 刘明敏 《组合机床与自动化加工技术》 北大核心 2026年第2期1-5,11,共6页
在多机器人路径规划的场景中,路径的平滑度和机器人的能耗是影响系统效率的关键因素。针对延迟添加约束多机器人路径规划算法(lazy constrains addition search for MAPF,LaCAM)存在规划出的路径不平滑、低层规划短视,路径耗能大等缺陷... 在多机器人路径规划的场景中,路径的平滑度和机器人的能耗是影响系统效率的关键因素。针对延迟添加约束多机器人路径规划算法(lazy constrains addition search for MAPF,LaCAM)存在规划出的路径不平滑、低层规划短视,路径耗能大等缺陷,提出了一种改进LaCAM算法。为减少机器人在运动过程中的转向次数,在单机器人路径搜索代价函数中引入转向惩罚因子;扩大低层规划的时间窗,设定软硬约束条件,引导机器人规避潜在冲突;在高层节点质量评估中综合考虑时间与耗能,并通过对冗余路径的检测与修复,引导LaCAM算法的高层搜索。实验结果表明,在不降低路径质量的前提下,改进LaCAM算法能有效减少转角数,缩短长度代价,并降低了耗能。 展开更多
关键词 多机器人路径规划 优先级规划 转向惩罚因子 路径引导 耗能优化
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耦合生态质量与服务的优先生态保护区空间识别研究——以长株潭城市群为例
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作者 谭德明 李凌波 林涛 《水土保持研究》 北大核心 2026年第1期225-236,247,共13页
[目的]实施基于生态质量与生态系统服务的生态保护和治理,保护具有重要生态价值和重要生态功能的地区,实现生态保护效益最大化。[方法]以长株潭城市群23个县级行政单位为研究对象,利用遥感生态指数(RSEI)代表生态质量(EEQ),结合生态系... [目的]实施基于生态质量与生态系统服务的生态保护和治理,保护具有重要生态价值和重要生态功能的地区,实现生态保护效益最大化。[方法]以长株潭城市群23个县级行政单位为研究对象,利用遥感生态指数(RSEI)代表生态质量(EEQ),结合生态系统服务综合指数(CES)对长株潭城市群(CZT)县域尺度优先生态保护区(PER)进行划分,从自然因子与社会因子两方面采用多尺度地理加权回归(MGWR)分析其驱动因素。[结果](1)2003—2023年长株潭城市群RSEI呈波动下降趋势,优秀区所占比例先由5.70%下降至3.83%,后上升至4.21%,直至12.61%,最后2023年回归5.93%;CES表现为逐期下降,较差地区的比例由2.12%上升至5.99%,一般地区的比例由1.77%下降到0.64%,在空间上表现为中心城区生态环境质量逐渐退化,非中心城区生态环境质量稳步提升;(2)提取综合表现前10%,20%和30%的县域,CES储量主要分布在研究区东侧,EQ储量主要分布在研究区边缘,综合生态储量主要分布在研究区东侧及西侧中部地区,均以林地利用类型为主;(3)在提取PER过程中,自然因子对生态环境质量与生态系统服务功能的影响较为显著,但随着社会经济发展,夜间灯光等社会经济因子对生态的影响逐渐增强。[结论]2003—2023年长株潭城市群RSEI与CES均呈下降趋势,Marxan结果建议将至少1718.42 km^(2)纳入CZT优先生态保护区。 展开更多
关键词 生态质量 生态系统服务 优先生态保护区 多尺度地理加权回归
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Multi-phase bus signal priority strategy at isolated intersections
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作者 王琳虹 别一鸣 +1 位作者 王殿海 宋现敏 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期430-435,共6页
To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought fo... To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought forward to settle the conflicts among multiple priority requests and arrange the optimal priority sequence. To avoid over saturation of the intersection, a conditional MPBSP algorithm that adopts early green and green extension strategies is developed to give priority to the bus with the highest priority level when green time that each phase runs makes its saturation degree not larger than 0. 95. Finally, the algorithm is tested in the VISSIM environment and compared with the normal signal timing algorithm. Sensitive analysis of the number of priority phases, bus demand, and volume to capacity ratios are conducted to quantify their impacts on the benefits of the MPBSP. Results show that the MPBSP strategy can effectively reduce bus delays, and with the increase in the number of priority phases, the reduction range of bus delays also increases. 展开更多
关键词 bus signal priority multiple phases early green green extension isolated intersection
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