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2011年全球发现的新矿物种
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作者 蔡剑辉 《岩石矿物学杂志》 CAS CSCD 北大核心 2024年第1期131-198,共68页
在系统梳理2011年度全球发现并经国际矿物学协会(IMA)新矿物与矿物分类命名专业委员会(CNMNC)批准的122个新矿物种资料的基础上,从矿物名称、晶体化学式、晶系和空间群、晶胞参数、主要粉晶数据、物理性质、光学性质、产地与产状、与其... 在系统梳理2011年度全球发现并经国际矿物学协会(IMA)新矿物与矿物分类命名专业委员会(CNMNC)批准的122个新矿物种资料的基础上,从矿物名称、晶体化学式、晶系和空间群、晶胞参数、主要粉晶数据、物理性质、光学性质、产地与产状、与其他矿物种的关系、矿物名称来源、化学反应和光谱学特征等方面归纳总结了这些新矿物的重要矿物学特征。并按照中国新矿物及矿物命名专业委员会颁布的《矿物种汉名审订条例》,对122个新矿物种的中文名称进行了审订。通过适时公布国际新矿物工作的新进展和新成果,并逐步完善和规范矿物种中文译名体系,为我国新矿物的发现和研究提供有科学价值的参考和借鉴,不断推动矿物种中文译名规范化与标准化的进程。 展开更多
关键词 新矿物 矿物种中文译名 晶体化学式 晶体结构特征 产地与产状 2011
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优化职业教育类型定位,走好通往专业高职之路——基于ISCED2011及《前往专业行当的通道》评核报告的新视角
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作者 袁益民 李芳苑 《江苏高职教育》 2024年第1期1-14,共14页
国际教育标准化分组2011通过职业专业与普通学术两种取向的划分,为国际层面更好地收集、比较和分析各国教育系统数据打开了一扇方便之门,很大程度上弥补了该分组1997版本在概念准确性和实践适切性方面的缺失。但囿于其对专业取向具体定... 国际教育标准化分组2011通过职业专业与普通学术两种取向的划分,为国际层面更好地收集、比较和分析各国教育系统数据打开了一扇方便之门,很大程度上弥补了该分组1997版本在概念准确性和实践适切性方面的缺失。但囿于其对专业取向具体定义的悬而未决,仍让国际间数据收集、比较和分析工作无所适从,留下了进一步研究解读和实践探索的空间。OECD最新发布的职业教育与培训评核报告《前往专业行当的通道:理解高等职业与专业第三级教育系统》较好地回应了这一问题,找到了务实可行的进一步定义方案,是ISCED2011修订版发布以来的一项重大进展。该报告以相关国家系统数据及调查数据为基础,分析了专业教育计划的实际现状,阐释了技术变革时代经济社会对理想技能的新要求,在继承和发展ISCED2011的专业取向构念基础上,提出了专业第三级教育计划分组的架构与思考。该报告提出的关于聚焦专业取向教育计划的政策辩论意见、“三向度”高教分组中的“二向度”专业教育计划分组方案以及专业取向教育的独特性、增值性和高等性等理念,对于我国把握终生学习背景下的职教类型定位、专业第三级教育计划分组下的贯通衔接以及技能型社会的技能需求和专业技能系统的治理等有诸多新的启示。正确理解和积极吸收相关有益经验,有利于我们优化职业教育类型定位,走好通往中国式现代化的专业高职之路。 展开更多
关键词 国际教育标准化分组 ISCED1997 ISCED2011 专业取向 专业技能 第三级教育 现代职业教育体系 高等职业教育
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基于“SHA2011”的某省综合医院治疗费用分布维度分析
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作者 王虹 张云霞 +1 位作者 韩颖 刘艳花 《卫生软科学》 2024年第1期78-81,共4页
[目的]分析某省综合医院治疗费用分布维度,为相关政策的完善调整提供参考。[方法]以某省2018年综合医院数据为基础,应用卫生费用核算体系2011核算方法,对该省综合医院治疗费用在不同维度的分布以及分布维度、筹资方案的矩阵分析结果进... [目的]分析某省综合医院治疗费用分布维度,为相关政策的完善调整提供参考。[方法]以某省2018年综合医院数据为基础,应用卫生费用核算体系2011核算方法,对该省综合医院治疗费用在不同维度的分布以及分布维度、筹资方案的矩阵分析结果进行描述性分析。[结果]该省综合医院治疗费用依次来源于社会医疗保险、家庭个人卫生支出、自愿筹资。从疾病流向看,33.5%流向循环系统疾病和消化系统疾病;从年龄流向看,45.43%流向60岁及以上人群;从性别流向看,53%流向男性群体;从医疗机构级别流向看,73.8%流向省市级医疗机构。[结论]居民疾病经济负担较重,重点疾病、重点人群、高级别医院占用的治疗费用较高。 展开更多
关键词 卫生费用核算体系2011 治疗费用 分布维度
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人工智能背景下Materials Project数据库在计算材料学课程教学中的应用
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作者 胡学敏 孙孪鸿 +1 位作者 陈晓玉 叶原丰 《科教文汇》 2024年第10期90-94,共5页
该文探讨了在人工智能背景下,Materials Project数据库在计算材料学课程教学中的应用和影响。Materials Project数据库是一个集成了AI和大数据技术的开放获取的材料库,能为学生提供海量的材料晶体结构和物性数据,使教学内容更为丰富,让... 该文探讨了在人工智能背景下,Materials Project数据库在计算材料学课程教学中的应用和影响。Materials Project数据库是一个集成了AI和大数据技术的开放获取的材料库,能为学生提供海量的材料晶体结构和物性数据,使教学内容更为丰富,让学生能通过亲自操作获取和分析数据,深入理解微观结构与物性之间的关系。这一新兴的教学模式不仅提升了学生的科研能力和创新思维能力,还有助于培养具备计算材料专业知识和多学科交叉的复合型人才。总体来说,人工智能时代下,大数据的引入为计算材料学课程带来新的活力,并对未来教育改革和实践产生了积极影响。 展开更多
关键词 人工智能 Materials project数据库 计算材料学教学
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Transcriptional regulation in the development and dysfunction of neocortical projection neurons 被引量:1
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作者 Ningxin Wang Rong Wan Ke Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期246-254,共9页
Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord... Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord.Appropriate development of cortical projection neurons is regulated by certain essential events such as neural fate determination,proliferation,specification,differentiation,migration,survival,axonogenesis,and synaptogenesis.These processes are precisely regulated in a tempo-spatial manner by intrinsic factors,extrinsic signals,and neural activities.The generation of correct subtypes and precise connections of projection neurons is imperative not only to support the basic cortical functions(such as sensory information integration,motor coordination,and cognition)but also to prevent the onset and progression of neurodevelopmental disorders(such as intellectual disability,autism spectrum disorders,anxiety,and depression).This review mainly focuses on the recent progress of transcriptional regulations on the development and diversity of neocortical projection neurons and the clinical relevance of the failure of transcriptional modulations. 展开更多
关键词 autism spectrum disorders COGNITION DIFFERENTIATION excitatory circuits intellectual disability NEOCORTEX neurodevelopmental disorders projection neuron specification transcriptional regulation
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日本“3·11”震灾后文学中的“反核”书写——以《神明2011》《晚年样式集》为例
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作者 周婕 孙立春 《语言与文化研究》 2024年第2期144-146,共3页
东日本大地震和由其引发的福岛核泄漏事故催生了以“3·11”大地震、核泄漏危机为主题的震灾后文学。本文基于川上弘美《神明2011》、大江健三郎《晚年样式集》这两部作品的分析,指出这两部作品在主题阐发上,分别通过新旧“神明观... 东日本大地震和由其引发的福岛核泄漏事故催生了以“3·11”大地震、核泄漏危机为主题的震灾后文学。本文基于川上弘美《神明2011》、大江健三郎《晚年样式集》这两部作品的分析,指出这两部作品在主题阐发上,分别通过新旧“神明观”的转变、过去侵入现在的历史书写,表达共同的反核主题,揭示了核危机下现代人共同的悲剧命运。 展开更多
关键词 震灾后文学 《神明2011 《晚年样式集》 反核
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2011—2022年我国妇幼保健机构申请和获得国家自然科学基金项目资助情况分析
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作者 王付曼 姚屹 《中国妇幼卫生杂志》 2024年第1期15-20,共6页
目的 分析2011—2022年我国妇幼保健机构申请和获得国家自然科学基金(National Natural Science Foundation of China,NSFC)项目资助情况,为妇幼保健机构科研能力建设提供参考。方法 运用NSFC大数据知识管理服务平台和全国妇幼保健机构... 目的 分析2011—2022年我国妇幼保健机构申请和获得国家自然科学基金(National Natural Science Foundation of China,NSFC)项目资助情况,为妇幼保健机构科研能力建设提供参考。方法 运用NSFC大数据知识管理服务平台和全国妇幼保健机构监测数据,分析NSFC项目申请、获资助、负责人等基本情况,比较获资助和未获资助机构在人力资源和承担科研课题项目上的差异性。结果 2011—2022年我国35家妇幼保健机构作为NSFC依托单位共申请项目861项,获资助率为10.57%;青年科学基金、面上项目、地区科学基金为主要申请和获资助类型,获资助率分别为7.27%、5.34%和15.21%,存在类别间和地区间差异。55.8%的项目负责人在首次获资助前参与过NSFC项目,且78.13%为高等院校牵头项目;项目负责人中,高级职称占58.25%、博士研究生学历占62.64%;获资助机构承担或独立承担科研课题项目数多于未获资助机构,差异有统计学意义(P <0.05)。结论 我国妇幼保健机构科研能力仍相对薄弱,人才储备和科研基础是项目申请成功的有利因素,妇幼保健机构应加强科研人才的引进与培养,以需求为牵引,关注政策导向,聚焦学术前沿,注重学科交叉,增强合作,推动科研创新能力提升,助力妇幼保健机构可持续、高质量地发展。 展开更多
关键词 国家自然科学基金 妇幼保健机构 获资助项目 人力资源 科研基础
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Diagnosis of indirectly driven double shell targets with point-projection hard x-ray radiography
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作者 Chao Tian Minghai Yu +17 位作者 Lianqiang Shan Fengjuan Wu Bi Bi Qiangqiang Zhang Yuchi Wu Tiankui Zhang Feng Zhang Dongxiao Liu Weiwu Wang Zongqiang Yuan Siqian Yang Lei Yang Zhigang Deng Jian Teng Weimin Zhou Zongqing Zhao Yuqiu Gu Baohan Zhang 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期50-62,共13页
We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on t... We present an application of short-pulse laser-generated hard x rays for the diagnosis of indirectly driven double shell targets. Coneinserted double shell targets were imploded through an indirect drive approach on the upgraded SG-II laser facility. Then, based on thepoint-projection hard x-ray radiography technique, time-resolved radiography of the double shell targets, including that of their near-peakcompression, were obtained. The backlighter source was created by the interactions of a high-intensity short pulsed laser with a metalmicrowire target. Images of the target near peak compression were obtained with an Au microwire. In addition, radiation hydrodynamicsimulations were performed, and the target evolution obtained agrees well with the experimental results. Using the radiographic images, arealdensities of the targets were evaluated. 展开更多
关键词 double projectION POINT
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Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems
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作者 You Zhao Xing He +1 位作者 Mingliang Zhou Tingwen Huang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1485-1498,共14页
The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on... The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization problems.In this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual vari-ables.By satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence rate.This only requires assuming convexity of the objective function.We validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments. 展开更多
关键词 Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.
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REFINEMENTS OF THE NORM OF TWO ORTHOGONAL PROJECTIONS
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作者 Xiaohui LI Meiqi LIU Chunyuan DENG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1229-1243,共15页
In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm ineq... In this paper,some refinements of norm equalities and inequalities of combination of two orthogonal projections are established.We use certain norm inequalities for positive contraction operator to establish norm inequalities for combination of orthogonal projections on a Hilbert space.Furthermore,we give necessary and sufficient conditions under which the norm of the above combination of o`rthogonal projections attains its optimal value. 展开更多
关键词 NORM orthogonal projection positive operator SPECTRAL block operator valued matrix
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Agricultural Investment Project Decisions Based on an Interactive Preference Disaggregation Model Considering Inconsistency
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作者 Xingli Wu Huchang Liao +1 位作者 Shuxian Sun Zhengjun Wan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3125-3146,共22页
Agricultural investment project selection is a complex multi-criteria decision-making problem,as agricultural projects are easily influenced by various risk factors,and the evaluation information provided by decisionm... Agricultural investment project selection is a complex multi-criteria decision-making problem,as agricultural projects are easily influenced by various risk factors,and the evaluation information provided by decisionmakers usually involves uncertainty and inconsistency.Existing literature primarily employed direct preference elicitation methods to address such issues,necessitating a great cognitive effort on the part of decision-makers during evaluation,specifically,determining the weights of criteria.In this study,we propose an indirect preference elicitation method,known as a preference disaggregation method,to learn decision-maker preference models fromdecision examples.To enhance evaluation ease,decision-makers merely need to compare pairs of alternatives with which they are familiar,also known as reference alternatives.Probabilistic linguistic preference relations are employed to account for the presence of incomplete and uncertain information in such pairwise comparisons.To address the inconsistency among a group of decision-makers,we develop a pair of 0-1mixed integer programming models that consider both the semantics of linguistic terms and the belief degrees of decision-makers.Finally,we conduct a case study and comparative analysis.Results reveal the effectiveness of the proposed model in solving agricultural investment project selection problems with uncertain and inconsistent decision information. 展开更多
关键词 Multiple criteria analysis preference disaggregation INCONSISTENCY probability linguistic preference relation investment project selection
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Spatial diversion and coordination of flood water for an urban flood control project in Suzhou, China
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作者 Yu Xu You-peng Xu +2 位作者 Qiang Wang Yue-feng Wang Chao Gao 《Water Science and Engineering》 EI CAS CSCD 2024年第2期108-117,共10页
Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as inten... Suzhou City,located in the Yangtze River Delta in China,is prone to flooding due to a complex combination of natural factors,including its monsoon climate,low elevation,and tidally influenced position,as well as intensive human activities.The Large Encirclement Flood Control Project(LEFCP)was launched to cope with serious floods in the urban area.This project changed the spatiotemporal pattern of flood processes and caused spatial diversion of floods from the urban area to the outskirts of the city.Therefore,this study developed a distributed flood simulation model in order to understand this transition of flood processes.The results revealed that the LEFCP effectively protected the urban areas from floods,but the present scheduling schemes resulted in the spatial diversion of floods to the outskirts of the city.With rainstorm frequencies of 10.0%to 0.5%,the water level differences between two representative water level stations(Miduqiao(MDQ)and Fengqiao(FQ))located inside and outside the LEFCP area,ranged from 0.75 m to 0.24 m and from 1.80 m to 1.58 m,respectively.In addition,the flood safety margin at MDQ and the duration with the water level exceeding the warning water level at FQ ranged from 0.95 m to 0.43 m and from 4 h to 22 h,respectively.Rational scheduling schemes for the hydraulic facilities of the LEFCP in extreme precipitation cases were developed ac-cording to food simulations under seven scheduling scenarios.This helps to regulate the spatial flood diversion caused by the LEFCP during extreme precipitation. 展开更多
关键词 Urban flooding Urban flood control project Rainstorm fregue ncy Flood simulation model Suzhou City
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Cascading multi-segment rupture process of the 2023 Turkish earthquake doublet on a complex fault system revealed by teleseismic P wave back projection method
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作者 Bonan Cao Zengxi Ge 《Earthquake Science》 2024年第2期158-173,共16页
In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back proj... In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back projection analysis.Data in two frequency bands(0.5-2 Hz and 1-3 Hz)are used in the imaging processes.The results show that the rupture of the first event extends about 200 km to the northeast and about 150 km to the southwest,lasting~90 s in total.The southwestern rupture is triggered by the northeastern rupture,demonstrating a sequential bidirectional unilateral rupture pattern.The rupture of the second event extends approximately 80 km in both northeast and west directions,lasting~35 s in total and demonstrates a typical bilateral rupture feature.The cascading ruptures on both sides also reflect the occurrence of selective rupture behaviors on bifurcated faults.In addition,we observe super-shear ruptures on certain fault sections with relatively straight fault structures and sparse aftershocks. 展开更多
关键词 2023 Turkish earthquake doublet back projection method cascading segmented rupture process coseismic triggering super-shear ruptures
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Economic significance and environmental impacts of the Song Dam Drinking Water Project(SDDWP)in Garhwal Himalaya
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作者 Vishwambhar Prasad SATI 《Regional Sustainability》 2024年第2期140-152,共13页
With the population growth through natural growth and migration,coupled with the city expansion,it is the fact that Dehradun City in India faces severe water scarcity.Therefore,the Song Dam Drinking Water Project(SDDW... With the population growth through natural growth and migration,coupled with the city expansion,it is the fact that Dehradun City in India faces severe water scarcity.Therefore,the Song Dam Drinking Water Project(SDDWP)is proposed to provide ample drinking water to Dehradun City and its suburban areas.This paper examined economic significance and environmental impacts of the SDDWP in Garhwal Himalaya,India.To conduct this study,we collected data from both primary and secondary sources.There are 12 villages and 3 forest divisions in the surrounding areas of the proposed dam project,of which 3 villages will be fully submerged and 50 households will be affected.For this study,50 heads of the households were interviewed in the 3 submerged villages.The questions mainly focused on economic significance,environmental impacts,and rehabilitation issues of the dam project.The findings of this study indicate that economic significance of the dam project is substantial,including providing ample water for drinking and irrigation,contributing to groundwater recharge,creating job opportunities,and promoting the development of tourism and fisheries in the Doon Valley.In terms of the rehabilitation of the affected people,there are only 50 households in need of rehabilitation.Currently,the arable land of these affected people is not sufficient to sustain their livelihoods.The entire landscape is fragile,rugged,and precipitous;therefore,the affected people are willing to rehabilitate to more suitable areas in the Doon Valley.Moreover,it is essential to provide them with sufficient compensation packages including the compensation of arable land,houses,cash,common property resources,institutions,belongingness,and cultural adaptation.On the other hand,the proposed dam project will have adverse environmental impacts including arable land degradation,forest degradation,loss of fauna and flora,soil erosion,landslides,and soil siltation.These impacts will lead to the ecological imbalances in both upstream and downstream areas.This study suggests that the affected people should be given sufficient compensation packages in all respects.Afforestation programs can be launched in the degraded areas to compensate for the loss of forest in the affected areas. 展开更多
关键词 Water scarcity Rehabilitation issues Song Dam Drinking Water project(SDDWP) Dehradun City Song River BASIN
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基于Microsoft Project的建筑施工项目管理分析
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作者 杨盛华 《中国厨卫》 2024年第7期82-84,共3页
在当前社会经济快速发展的情况下,建设工程数量不断增加,而传统的手工记录方式已经无法满足现代建设工程的需求。因此,采用先进的计算机技术来辅助建筑施工项目管理已成为当今建筑业发展的趋势。Microsoft Project作为一种专业的项目管... 在当前社会经济快速发展的情况下,建设工程数量不断增加,而传统的手工记录方式已经无法满足现代建设工程的需求。因此,采用先进的计算机技术来辅助建筑施工项目管理已成为当今建筑业发展的趋势。Microsoft Project作为一种专业的项目管理软件,具有良好的数据存储和可视化展示功能,可以有效地提高建筑施工项目的质量和效率。文章分析了如何利用Microsoft Project软件进行建筑施工项目管理,并对该方法的应用效果进行评估,以期为今后的建筑施工项目管理提供参考价值。 展开更多
关键词 Microsoft project 建筑施工 项目管理
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How do lateral septum projections to the ventral CA1 influence sociability?
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作者 Dan Wang Di Zhao +12 位作者 Wentao Wang Fengai Hu Minghu Cui Jing Liu Fantao Meng Cuilan Liu Changyun Qiu Dunjiang Liu Zhicheng Xu Yameng Wang Yu Zhang Wei Li Chen Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1789-1801,共13页
Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role ... Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role of the connections between the LS and its downstream brain regions in social behavio rs remains unclea r.In this study,we conducted a three-chamber test using electrophysiological and chemogenetic approaches in mice to determine how LS projections to ventral CA1(vCA1)influence sociability.Our res ults showed that gamma-aminobutyric acid(GABA)-e rgic neuro ns were activated following social experience,and that social behavio rs were enhanced by chemogenetic modulation of these neurons.Moreover,LS GABAergic neurons extended their functional neural connections via vCA1 glutamatergic pyramidal neurons,and regulating LSGABA→vCA1Gluneural projections affected social behaviors,which were impeded by suppressing LSprojecting vCA1 neuronal activity or inhibiting GABAAreceptors in vCA1.These findings support the hypothesis that LS inputs to the vCA1 can control social prefe rences and social novelty behaviors.These findings provide new insights rega rding the neural circuits that regulate sociability. 展开更多
关键词 chemogenetics GABA receptor GABAergic neurons glutamatergic neurons lateral septum neural excitability neural projection social novelty social preference ventral CA1
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Spatial Variation and Trend of Extreme Precipitation in Africa during 1981-2019 and Its Projected Changes at the End of 21st Century
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作者 Fabien Habiyakare Tong Jiang +3 位作者 Ibrahim Yahaya Daudi Ndabagenga James Kagabo Buda Su 《Journal of Geoscience and Environment Protection》 2024年第3期192-221,共30页
This study comprehensively examines the patterns and regional variation of severe rainfall across the African continent, employing a suite of eight extreme precipitation indices. The analysis extends to the assessment... This study comprehensively examines the patterns and regional variation of severe rainfall across the African continent, employing a suite of eight extreme precipitation indices. The analysis extends to the assessment of projected changes in precipitation extremes using five General Circulation Models (GCMs) from Coupled Model Intercomparison Project Phase 6 (CMIP6) under four Shared Socioeconomic Pathways (SSPs) scenarios at the long-term period (2081-2100) of the 21<sup>st</sup> century. Furthermore, the study investigates potential mechanisms influencing precipitation extremes by correlating extreme precipitation indices with oceanic system indices, specifically Ni?o 3.4 for El Ni?o-Southern Oscillation (ENSO) and Dipole Mode Index (DMI) for the Indian Ocean Dipole (IOD). The findings revealed distinct spatial distributions in mean trends of extreme precipitation indices, indicating a tendency toward decreased extreme precipitation in North Africa, Sahel region, Central Africa and the Western part of South Africa. Conversely, West Africa, East Africa and the Eastern part of South Africa exhibit an inclination toward increased extreme precipitation. The changes in precipitation extreme indices indicate a general rise in both the severity and occurrence of extreme precipitation events under all scenarios by the end of the 21<sup>st</sup> century. Notably, our analysis projects a decrease in consecutive wet days (CWD) in the far-future. Additionally, correlation analysis highlights significant correlation between above or below threshold rainfall fluctuation in East Africa and South Africa with oceanic systems, particularly ENSO and the IOD. Central Africa abnormal precipitation variability is also linked to ENSO with a significant negative correlation. These insights contribute valuable information for understanding and projecting the dynamics of precipitation extreme in Africa, providing a foundation for climate adaptation and mitigation efforts in the region. 展开更多
关键词 Extreme Precipitation Mann-Kendall Trend projections Oceanic System AFRICA
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Contractor-Related Factors and Performance of Bridge Construction Projects Implemented by Kenya National Highways Authority (KeNHA) Kenya
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作者 Joan Anyika Otike Charles Kabubo Victoria Okumu 《Open Journal of Civil Engineering》 2024年第2期214-224,共11页
The performance of bridge projects in Kenya is poor in terms of completion by schedule, cost, and quality (scope). Yet, there is less evidence of empirical research on what factors contribute to this outcome. This stu... The performance of bridge projects in Kenya is poor in terms of completion by schedule, cost, and quality (scope). Yet, there is less evidence of empirical research on what factors contribute to this outcome. This study aimed to bridge this gap by examining the effects of contractor-related factors on the performance of bridge construction projects in Kenya through a case study of the Bridge projects Implemented by the Kenya National Highway Agency (KeNHA). The theory of constraints (TOC) was adopted as its theoretical framework. Descriptive research was used, and the target population was 18 bridge construction projects, which were the units of analysis from 2012 to 2022. In each of these projects, 18 respondents, namely clients, consultants, contractors, engineers, environment and social guards, project managers, stakeholders, subcontractors, technical advisors, and inspectors, were included in a target population of 144 respondents. A census was conducted and a structured questionnaire was administered from which a response rate of 68% was achieved. The information was analyzed using descriptive, correlation, and multiple linear regression analysis. The contractor-related factors considered in the study were staff and management factors. The findings indicated that staff and management factors had a positive and significant outcome on performance of bridge construction projects. The study recommends continuous training and a safe learning environment for staff to improve their skills and performance in future projects. The study also recommends that a special category for bridge contractors be created in Kenya’s National Construction Authority rankings to ensure that only qualified contractors implement the Bridge projects. 展开更多
关键词 Staff Factors Management Factors Performance Bridge projects KeNHA
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Computational Quantification of Map Projection Distortion by Fractal Dimension of Coastlines
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作者 Franklin Lee 《Journal of Applied Mathematics and Physics》 2024年第5期1890-1903,共14页
Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short w... Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short when evaluating actual geographic features. In our study, we took a novel approach by analyzing map projection distortion from a geometric perspective. We computed the fractal dimensions of different stretches of coastline before and after projection using the divide-and-conquer algorithm and image processing. Our findings revealed that map projections, even when preserving basic shapes, inevitably stretch and compress coastlines in diverse directions. This analysis method provides a more realistic and practical way to measure map-induced distortions, with significant implications for cartography, geographic information systems (GIS), and geomorphology. By bridging the gap between theoretical analysis and real-world features, this method greatly enhances accuracy and practicality when evaluating map projections. 展开更多
关键词 Map projection Distortion COASTLINE Fractal Dimension CARTOGRAPHY Geographic Information Systems
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Multi-Criteria Wildfire Risk Hazard Assessment in GIS Environment: Projection for the Future and Impact on RES Projects Installation Planning
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作者 Aggelos Pallikarakis Flora Konstantopoulou 《Journal of Geoscience and Environment Protection》 2024年第5期242-265,共24页
It is alarming for the fact that Wildfires number, severity and consequently impact have significantly increased during the last years, an aftermath of the Climate Change. One of the most affected areas worldwide is M... It is alarming for the fact that Wildfires number, severity and consequently impact have significantly increased during the last years, an aftermath of the Climate Change. One of the most affected areas worldwide is Mediterranean, due to the unique combination of its type of vegetation and demanding climatic conditions. This research is focused on the Region of Epirus in Greece, an area with significant natural vegetation and a range of geomorphological aspects. In order to estimate the Wildfire Risk Hazard, several factors have been used: geomorphological (slope, aspect, elevation, TWI, Hydrographic network), social (Settlements and landfils, roads, overhead lines and substations), environmental (land cover) and climatic (Fire Weather Index). Through a multi-criteria decision analysis (MCDA) and an analytic hierarchy process (AHP) in a GIS environment, the Wildfire Risk Hazard has been estimated not only for current conditions but also for future projections for the near future (2031-2060) and the far future (2071-2100). The selected case study includes the potential impact of the Wildfires to the installed (or targeted to be installed) RES projects in the studied region. 展开更多
关键词 RES projects Greece Epirus Analytic Hierarchy Process Multi-Criteria Decision Analysis
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