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Primary Study on the Index System of Underground Space Utilization in Urban Parks
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作者 李静 魏璐璐 程佳佳 《Journal of Landscape Research》 2010年第4期15-19,共5页
The feasibility of underground space utilization in urban parks, the function and scale of underground space were explored, also the role, composition, quantification of the index system of underground space utilizati... The feasibility of underground space utilization in urban parks, the function and scale of underground space were explored, also the role, composition, quantification of the index system of underground space utilization in urban parks were analyzed, and the corresponding conceptual framework of index system were proposed. 展开更多
关键词 PARK UNDERGROUND space index
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Proposal of Landscape Space Transfer Index and Changes of Landscape Area Based on Transfer Matrix——With Yutian County in Xinjiang as a Study Case
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作者 贺凌云 海米提.依米提 蔡永革 《Journal of Landscape Research》 2010年第7期26-29,共4页
The most significant changes of landscape in a certain period are landscape area changes and spatial changes of landscape patches.Based on transfer matrix and total amount change of landscape area,landscape space tran... The most significant changes of landscape in a certain period are landscape area changes and spatial changes of landscape patches.Based on transfer matrix and total amount change of landscape area,landscape space transfer index and landscape area change index were established,and then applied to analyze plain oasis and desert in Yutian County,Xinjiang Uyghur Nationality Autonomous Region,the results showed that landscape space transfer in this region was drastic,but total landscape area changed only slightly,thus space transfer index was much higher than area change index,which indicated that landscapes in arid area were given with particular spatial undulant features and sensitivity,while man-made landscapes(artificial oasis) are stable and expanding to some extent.With landscape space transfer index as the comprehensive indicator,space transfer intensity of landscape within a certain period can be demonstrated,which is favorable for the comparison of landscape change intensity among different types and within different periods,in addition,some macroscopic change features of landscapes can also be reflected by comprehensively analyzing landscape space transfer index and landscape area change index. 展开更多
关键词 ARID area LANDSCAPE space TRANSFER index Area change index
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Establishment and Application of Integrated Evaluation Index System for Urban Leisure Sports Space in China
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作者 Yu Feng 《Journal of Zhouyi Research》 2014年第3期61-62,共2页
关键词 综合评价指标体系 中国城市 体育发展 运动空间 休闲 层次分析模型 应用 层次分析法
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The Index of Invariant Subspaces of Bounded below Operators on Banach Spaces
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作者 George Chailos 《Advances in Pure Mathematics》 2012年第2期124-127,共4页
For an operator on a Banach space , let be the collection of all its invariant subspaces. We consider the index function on and we show, amongst others, that if is a bounded below operator and if , , then If in additi... For an operator on a Banach space , let be the collection of all its invariant subspaces. We consider the index function on and we show, amongst others, that if is a bounded below operator and if , , then If in addition are index 1 invariant subspaces of , with nonzero intersection, we show that . Furthermore, using the index function, we provide an example where for some , holds . 展开更多
关键词 index Invariant SUBspaceS BOUNDED below OPERATORS BANACH spaceS
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基于AHP-SPACE矩阵的镇雄县乡村产业发展战略研究
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作者 张紫涵 王静 《智慧农业导刊》 2024年第10期25-30,共6页
该研究构建县域乡村产业评价指标体系,明确乡村各产业战略地位,制定科学的产业发展优化措施,改善农民生活、推进农村现代化,为县域乡村产业发展决策提供参考依据。通过战略地位和行动评价SPACE矩阵,从财务优势、竞争优势、环境稳定性和... 该研究构建县域乡村产业评价指标体系,明确乡村各产业战略地位,制定科学的产业发展优化措施,改善农民生活、推进农村现代化,为县域乡村产业发展决策提供参考依据。通过战略地位和行动评价SPACE矩阵,从财务优势、竞争优势、环境稳定性和产业优势共4个方面构建乡村产业评价指标体系。应用层次分析法(AHP)确定指标权重。镇雄县农林牧渔具有竞争型战略地位,工业,建筑业,交通运输、仓储和邮政业,批发零售业,房地产业及其他服务业属于进取型战略地位,住宿和餐饮业为防御型战略地位,金融业为保守型战略地位。镇雄县发展起步较晚,但乡村振兴战略和政府支持为其带来巨大潜力。未来应重点发展乡村主导产业,增加投资力度,推动产业快速发展。 展开更多
关键词 space矩阵 乡村产业 评价指标 战略研究 镇雄县
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基于Cite Space的中医药和凝血指标研究的文献计量学分析 被引量:1
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作者 徐佳 李文晴 李琦 《标记免疫分析与临床》 CAS 2023年第1期12-19,36,共9页
目的为使研究者了解目前中医药和凝血功能领域的研究现状和进展,本文运用文献计量学和Cite Space软件对该领域的相关文献进行了分析。方法通过检索中国知网(CNKI)和万方数据库从建库至2022年5月8日所收录的文献,进行筛选后最终获得562... 目的为使研究者了解目前中医药和凝血功能领域的研究现状和进展,本文运用文献计量学和Cite Space软件对该领域的相关文献进行了分析。方法通过检索中国知网(CNKI)和万方数据库从建库至2022年5月8日所收录的文献,进行筛选后最终获得562篇文献进行可视化分析,包括关键词共现图谱、聚类分析、时间线图谱、突现词检测等。结果中医药和凝血功能研究的发文量整体呈平稳增长的趋势;词频排名前十的依次为凝血酶原时间(PT)、纤维蛋白原(Fbg)、活化部分凝血活酶时间(APTT)、D-二聚体、凝血酶时间(TT)、凝血功能障碍、血小板计数、血液流变学、脑梗死、静脉血栓;突现强度最高的中药关键词为丹参,氧化应激水平、炎症因子和免疫反应等突现词近年逐渐成为主流,有望持续成为研究热点。结论目前中医药和凝血功能领域的研究已并非仅停留在单体和传统检验指标研究上,而是在此基础上扩展至复方制剂、中医治法、新型血栓分子标志物、机制研究等多方面,炎症和免疫机制已有成为中医药与凝血功能研究的重点和热点的趋势。 展开更多
关键词 中医药 凝血指标 CITEspace 文献计量学 炎症
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Open Space Ratio的译名、概念辨析与适用价值 被引量:6
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作者 陈璐 周剑云 +1 位作者 黎淑翎 庞晓媚 《城市规划》 CSSCI CSCD 北大核心 2020年第8期98-106,111,共10页
Open Space Ratio(OSR)是《1961纽约市区划决议案》中居住环境控制的核心概念与重要指标,自1990年代始国内的许多学者引进这个概念,并倡导作为规划控制指标,因此也催生了中文术语"空地率"。本文系统梳理国内有关"OSR&qu... Open Space Ratio(OSR)是《1961纽约市区划决议案》中居住环境控制的核心概念与重要指标,自1990年代始国内的许多学者引进这个概念,并倡导作为规划控制指标,因此也催生了中文术语"空地率"。本文系统梳理国内有关"OSR"和"空地率"研究的30余年学术文献,基于《1961纽约市区划决议案》的法律文本,对OSR的译名及其概念作出全面的阐释,澄清了OSR指标的意义、应用目的及其范围,辨析了OSR与中文术语"空地率"本质性的概念差异,建议将OSR指标引入控制性详细规划的居住环境控制,调整和完善我国控制性详细规划的指标控制体系。 展开更多
关键词 开敞空间率 空地率 规划指标 区划 控制性规划
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DISTRIBUTION PATTERNS OF LEAF AREA INDEX FOR MAJOR CONIFEROUS FOREST TYPES IN CHINA 被引量:4
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作者 Luo Tianxiang Li Wenhua Zhao Shidong Commission for Integrated Survey of Natural Resources, CAS, Beijing 100101 The People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第4期61-73,共13页
Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfull... Leaf area index (LAI) of natural vegetation is recognized as the most important variable for measuring vegetation structure over large areas, and for relating it to energy and mass exchange, which has been successfully estimated from satellite resolution sensors. In this paper, according to the statistical analysis based on a lot of forest plots, the mathematical models of LAI distribution patterns in the hydro thermal spaces for five coniferous forest types in China were established. For the cold temperate larch forests growing in the dry and cold climate, their LAI increases with the increasing of warm index and precipitation in the way of hyperbolic quadratic surface. For the cold temperate spruce fir forests and temperate Pinus tabulaeformis forests, their LAI is negatively related to the annual mean air temperature in the way of the natural exponential curve, in order to adapt to the water oppressed environments. For the subtropical Pinus massoniana forests and Cunninghamia lanceolata forests growing in the warm and moist climate, their LAI is related to the annual mean air temperature in the way of the parabolic quadratic curve. 展开更多
关键词 leaf area index hydro thermal space distribution pattern.
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Characteristics Analysis of Urban Space Expansion in Luoyang, China 被引量:2
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作者 Kaiguang Zhang Hongling Meng +1 位作者 Mingting Ba Yanmin Sun 《Journal of Geoscience and Environment Protection》 2022年第1期123-139,共17页
The characteristics of urban space expansion reflect the changes of urban space layout and space structure, as well as the urban developing direction and urban orientation in the future. Based on the remote sensing im... The characteristics of urban space expansion reflect the changes of urban space layout and space structure, as well as the urban developing direction and urban orientation in the future. Based on the remote sensing image data of 1990, 2000, 2010 and 2020, this paper analyzes the urban space expansion characteristics of Luoyang, by using the urban land compaction index, expansion intensity index and centroid distribution in 4 time sections and 3 periods. The results show that: 1) the urban land area of Luoyang has expanded rapidly, the urban planning policy has successfully guided the urban expansion. 2) In the first period, the urban expansion belongs to the rapid expansion type, mainly filling the built-up area and natural expansion to outward;the second period is of high-speed expansion type, the urban expansion mainly enlarges the urban framework, then fills the expanded district, and the influence of urban natural growth factor is very small;the third period belongs to the high-speed expansion type, and the expansion rate is significantly lower than that in the second period, the urban expansion is mainly to fill in the urban framework enlarged in the previous period<span><span><span style="font-family:;" "=""> and</span></span></span><span><span><span style="font-family:;" "=""> continue to enlarge the urban framework, and the influence of urban natural growth factor is very little. 3)</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "="">The urban land centroid gradually migrates to the southeast with the azimuth of 151.47</span></span></span>&#176;<span "="">, the annual migration distance is of 138.29</span><span "=""> </span><span "="">m. The migration rate in the second period is the fastest, which is about 7.43 times that of the first period, and 2.70 times that of the third period. In the first period, the urban land is mainly expanded to southward, with the main azimuth of 201.13<span style="white-space:normal;">&#176;</span>. Compared with the urban land centroid in 2000, the urban land in the second period mainly expands to east-southeast and southward along the azimuths of 141.92<span style="white-space:normal;">&#176;</span> and 154.17<span style="white-space:normal;">&#176;</span> respectively. Compared with the urban centroid in 2010, the urban land in the third period mainly expands in the orientations of southeast and eastward along the azimuth of 96.24<span style="white-space:normal;">&#176;</span> and 133.45<span style="white-space:normal;">&#176;</span>.</span> 展开更多
关键词 Urban space Expansion Compaction index Expand Intensity index Expand Orientation Centroid Migration Luoyang
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The Distribution of an Index of Dissimilarity for Two Samples from a Uniform Population 被引量:1
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作者 Giovanni Girone Antonella Nannavecchia 《Applied Mathematics》 2013年第7期1028-1037,共10页
In this paper the authors study the sample behavior of the Gini’s index of dissimilarity in the case of two samples of equal size drawn from the same uniform population. The paper present the analytical results obtai... In this paper the authors study the sample behavior of the Gini’s index of dissimilarity in the case of two samples of equal size drawn from the same uniform population. The paper present the analytical results obtained for the exact distribution of the index of dissimilarity for sample sizes n ≤ 8. This result was obtained by expressing the index of dissimilarity as a linear combination of spacings of the pooled sample. The obtained results allow to achieve the exact expressions of the moments for any sample size and, therefore, to highlight the main features of the sampling distributions of the index of dissimilarity. The present study can enhance inferential statistical aspects about one of the main contributions of Gini. 展开更多
关键词 index of DISSIMILARITY UNIFORM DISTRIBUTION SPACINGS
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Driving Mechanism of Urban Space Expansion in Luoyang, China
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作者 Kaiguang Zhang Hongling Meng +1 位作者 Mingting Ba Danhuan Wen 《Journal of Geographic Information System》 2022年第6期589-599,共11页
Urban space expansion is the result of the interaction between internal and external forces of the urban. Based on the remote sensing image data of 1990, 2000, 2010, and 2020, and the social and economic development d... Urban space expansion is the result of the interaction between internal and external forces of the urban. Based on the remote sensing image data of 1990, 2000, 2010, and 2020, and the social and economic development data, this paper analyzes the driving mechanism of the Luoyang space expansion characteristics and its correlation characteristics. By using urban land use efficiency index, urban expansion elastic index;urban allometric growth index, and grey correlation analysis in 4 times sections and 3 periods. The research results show that the urban space expansion of Luoyang mainly comes from the needs and support of economic development, the coordination between urban space expansion and population development is poor, and urban space expansion effectively attracts the inflow of external funds, and the settlement of migrants, drives the development of the tertiary industry, and increases the local revenue. 展开更多
关键词 Urban space Expansion Urban Land Use Efficiency index Urban space Expansion Elasticity index Urban Allometric Growth index Grey Correlation Analysis Luoyang
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Predicting of Power Quality Steady State Index Based on Chaotic Theory Using Least Squares Support Vector Machine 被引量:2
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作者 Aiqiang Pan Jian Zhou +2 位作者 Peng Zhang Shunfu Lin Jikai Tang 《Energy and Power Engineering》 2017年第4期713-724,共12页
An effective power quality prediction for regional power grid can provide valuable references and contribute to the discovering and solving of power quality problems. So a predicting model for power quality steady sta... An effective power quality prediction for regional power grid can provide valuable references and contribute to the discovering and solving of power quality problems. So a predicting model for power quality steady state index based on chaotic theory and least squares support vector machine (LSSVM) is proposed in this paper. At first, the phase space reconstruction of original power quality data is performed to form a new data space containing the attractor. The new data space is used as training samples for the LSSVM. Then in order to predict power quality steady state index accurately, the particle swarm algorithm is adopted to optimize parameters of the LSSVM model. According to the simulation results based on power quality data measured in a certain distribution network, the model applies to several indexes with higher forecasting accuracy and strong practicability. 展开更多
关键词 CHAOTIC THEORY Least SQUARES Support Vector Machine (LSSVM) Power Quality STEADY State index Phase space Reconstruction Particle SWARM Optimization
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中国潜在自主可控关键产品识别与突破路径研究 被引量:2
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作者 王文平 吴来凤 《科技进步与对策》 CSSCI 北大核心 2024年第2期13-24,共12页
系统分析中国潜在自主可控关键产品突破时序路径,是逆全球化背景下全面防范和化解“卡脖子”潜在风险的关键。基于1995—2021年243个国家(地区)出口产品数据构建产品空间网络模型,识别全球核心产品及中国潜在自主可控关键产品,基于产品... 系统分析中国潜在自主可控关键产品突破时序路径,是逆全球化背景下全面防范和化解“卡脖子”潜在风险的关键。基于1995—2021年243个国家(地区)出口产品数据构建产品空间网络模型,识别全球核心产品及中国潜在自主可控关键产品,基于产品能力和网络核心性构建优先度指数,挖掘潜在自主可控关键产品突破路径。研究表明,在2021年核心度前10%的124种全球核心产品中,共有54种中国潜在自主可控关键产品,其突破路径为:充分利用机械与电力设备、基本金属制品、化工产品等领域已有的产品能力基础,优先突破光学显影和金属工艺等领域的基础关键产品,再进一步突破机械与电力设备、光学与医疗等精密仪器、塑料与橡胶制品业等领域高端关键产品。 展开更多
关键词 潜在自主可控关键产品 关键核心产品 产品空间网络 优先度指数
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街道的空间整合度与风场耦合性及其优化研究——以武汉市为例
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作者 尹杰 陈林 +2 位作者 宋斯琦 许华华 向澄 《武汉工程大学学报》 CAS 2024年第2期217-224,共8页
为研究街道形态影响行人的步行可达性和通风效能,采用计算流体力学(CFD)模拟与空间句法Depth map模拟相结合的方法,探究街道形态风场特征与空间整合度的耦合性关系,总结耦合性规律,得到结论:(1)中间左右错位式的通风效果最明显,但是整... 为研究街道形态影响行人的步行可达性和通风效能,采用计算流体力学(CFD)模拟与空间句法Depth map模拟相结合的方法,探究街道形态风场特征与空间整合度的耦合性关系,总结耦合性规律,得到结论:(1)中间左右错位式的通风效果最明显,但是整合度明显低于前后对齐并列式;(2)建筑前后错接式的通风效果最明显,但是整合度最低;(3)建筑前后错位式的整合度最高,显著高于前后对齐并列式,但是通风效果最差;(4)长街道界面的通风效果较好,但是整合度最低,短街道界面的整合度最高。通过优化街道空间形态,调整建筑形态、建筑布局、沿街界面等措施,使街道活跃度和通风风场相叠合,为行人的步行环境创造良好的通风气候环境。 展开更多
关键词 空间句法 计算流体力学模拟 空间整合度 空间优化
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北京健康街道评价方法研究
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作者 崔旭川 马瑞 《城市交通》 2024年第2期45-53,共9页
街道是提升城市空间品质的重要场所,也是推动街区更新与治理完善的重要领域。以健康街道评价为研究对象,首先对伦敦健康街道方法进行解读,强调健康街道评价与城市治理、评价结果与实施改善的紧密联系。在伦敦健康街道方法基础上,结合北... 街道是提升城市空间品质的重要场所,也是推动街区更新与治理完善的重要领域。以健康街道评价为研究对象,首先对伦敦健康街道方法进行解读,强调健康街道评价与城市治理、评价结果与实施改善的紧密联系。在伦敦健康街道方法基础上,结合北京实际发展背景丰富评价内涵,提出以居民身心健康为目标,综合考虑社会、经济、环境等因素的北京健康街道评价体系,具体包括8个一级指标和20个二级指标,分为必评项、减分项和加分项三类。选取北京市三里屯地区亮马河路段作为试点,对街道现状进行主观评价和客观评价,并提出相应的改善方案建议。概念设计后评价结果显示,街道安全舒适、空间环境品质、健步悦骑友好等方面指标分数明显提升。最后指出,健康街道评价作为一种规划技术手段将在城市治理领域发展成为潜在的重要工具。 展开更多
关键词 街道空间治理 评价指标体系 健康街道 非机动交通 北京市
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FIXED POINT INDEX THEORY FOR WEAKLY INWARD MAPPINGS
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作者 韩志清 《Acta Mathematica Scientia》 SCIE CSCD 1997年第4期455-462,共8页
In this paper we define a fixed point index theory for locally Lip., completely continuous and weakly inward mappings defined on closed convex sets in general Banach spaces where no other artificial conditions are imp... In this paper we define a fixed point index theory for locally Lip., completely continuous and weakly inward mappings defined on closed convex sets in general Banach spaces where no other artificial conditions are imposed. This makes ns to deal with these kinds of mappings more easily. As obvious applications, some results in [3],[5],[7],[9],[10] are deepened and extended. 展开更多
关键词 weakly inward mappings fixed point index theory differential equations in Banach spaces
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存量地下空间更新价值评估体系研究
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作者 胡斌 李雨姗 张明子 《地下空间与工程学报》 CSCD 北大核心 2024年第1期17-22,41,共7页
存量地下空间在补充地面空间资源、完善城市设施方面具有巨大的潜力,但在发展过程中凸显出功能集聚但空间匮乏、品质参差且风貌缺失、功能错位且动迁成本高、停车供给不足又缺乏联动等众多问题。因其自身特点复杂且受到的限制较多,如对... 存量地下空间在补充地面空间资源、完善城市设施方面具有巨大的潜力,但在发展过程中凸显出功能集聚但空间匮乏、品质参差且风貌缺失、功能错位且动迁成本高、停车供给不足又缺乏联动等众多问题。因其自身特点复杂且受到的限制较多,如对于公众开放性不足,涉及多个发展目标,影响方案决策的因素较多,以及配套管理机制滞后等,加之缺乏高效的价值评估方法,导致在对其进行更新再利用时面临利用方式的单一和利用效率的不足。本文从全要素研究分析的角度出发,以现状质量、更新需求、成本投入和可获效益4个需求准则进行价值评估指标的选取,经过对多种评估方法的对比,选用特征价格法用于城市存量地下空间价值评估,以存量地下空间更新的微观形成机制估算潜在价值,采用定性分析与定量评价相结合的方式,在重要因素与更新利用之间建立回归模型,选择拟合度较好的半对数模型,并提出借助多元数据,提高评估的准确性,拟合存量地下空间的更新价值分布,以期为存量地下空间的高效、高品质更新利用提供参考。 展开更多
关键词 地下空间 存量更新 价值评估 指标选取 多元数据
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基于百度指数的晋商大院网络关注度时空特征研究
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作者 邵秀英 宋晓楠 《忻州师范学院学报》 2024年第5期31-38,共8页
晋商文化旅游作为文化旅游的一种特殊类型,对于中国优秀传统文化的弘扬和传承具有重要意义。文章以晋商大院网络关注度为研究对象,通过提取2017—2022年百度指数数据,采用多指数分析方法从时间和空间两个维度分析了山西晋商大院网络关... 晋商文化旅游作为文化旅游的一种特殊类型,对于中国优秀传统文化的弘扬和传承具有重要意义。文章以晋商大院网络关注度为研究对象,通过提取2017—2022年百度指数数据,采用多指数分析方法从时间和空间两个维度分析了山西晋商大院网络关注度特征。研究发现,晋商大院网络关注度的省域空间分布符合“空间距离衰减定律”,同时在时间分布上,存在较小的淡旺季,“五一”和“十一”的关注度是集中在黄金周的前期,而“春节”是集中在其后期。 展开更多
关键词 晋商大院 网络关注度 百度指数 时空特征
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基于粒子群的旧工业建筑再利用空间优化算法
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作者 白朝勤 林丁 《计算机仿真》 2024年第4期305-309,共5页
为了解决土地资源紧张的问题,优化旧工业建筑空间,提高建筑利用空间紧密度,实现空间再利用,提出基于粒子群的旧工业建筑再利用空间优化算法。将土地利用适宜性最大化、用地紧凑度最大化和转化成本最小化作为优化目标,构建空间优化模型,... 为了解决土地资源紧张的问题,优化旧工业建筑空间,提高建筑利用空间紧密度,实现空间再利用,提出基于粒子群的旧工业建筑再利用空间优化算法。将土地利用适宜性最大化、用地紧凑度最大化和转化成本最小化作为优化目标,构建空间优化模型,建立旧工业建筑再利用空间优化目标函数,在相关条件的约束下采用粒子群算法求解上述目标函数,实现旧工业建筑再利用空间的优化。仿真结果表明,所提方法的地类转换成本低,总适宜度、生态协调性和社会效益高,空间紧凑度高,优化效率高。 展开更多
关键词 粒子群算法 旧工业建筑 用地紧凑度 再利用空间优化 地类转换成本
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Energy-Momentum Density of Non-Diagonal Bianchi Type Space-Time in General Relativity and Teleparallel Gravity
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作者 Ragab M. Gad Haifaa A. Alharbi 《Journal of Applied Mathematics and Physics》 2021年第9期2355-2375,共21页
We calculated the energy-momentum density of non-diagonal Bianchi type space-time in two different theories of gravity, General relativity (GR) and the theory of Teleparallel gravity (TG). Firstly, by applying Einstei... We calculated the energy-momentum density of non-diagonal Bianchi type space-time in two different theories of gravity, General relativity (GR) and the theory of Teleparallel gravity (TG). Firstly, by applying Einstein, Landau-Lifshitz, Bergmann-Thomson and M<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#248;</span></span></span>ller prescriptions, using double index complexes in <strong>GR</strong>. Secondly, in the frame work of <strong>TG</strong>, we used the energy momentum complexes of Einstein, Bergmann-Thomson and Landau-Lifshitz. We also study the spacial cases of non-diagonal Bianchi type space-time <strong>BII</strong>, <strong>BVIII</strong> and <strong>BIX</strong>. We obtained the same energy-momentum density components for Einstein and Bergmann-Thomson prescriptions for the above four mentioned space-times that we considered in our work. Also, we found that the energy density component in M<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#248;</span></span></span>ller prescription is zero for all Bianchi types space-times in GR. Furthermore, we show that if the metric components are functions of time t alone, then the total gravitational energy is identically zero. 展开更多
关键词 Energy-Momentum Densities Double index Complexes Teleparallel Gravity Bianchi Type space Time
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