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1.
借助词云技术和CiteSpace可视化软件对1998—2021年中国知网(CNKI)数据库中发表在CSSCI期刊上的3736篇儒家文化文献进行分析。从文献年度发文量、期刊来源、研究机构和核心作者分布情况四个方面来展示儒家文化领域的研究现状;通过对高频关键词、高中心性和关键词聚类分析,探索归纳这一时期儒家文化领域的研究热点;通过绘制关键词共现时序图谱和突变知识图谱,探究儒家文化领域的演变态势和热点前沿,以期为后续研究提供参考和借鉴。  相似文献   

2.
为探索我国公共卫生领域的研究现状、热点主题及前沿趋势,以《中国公共卫生》为来源期刊收集文献,运用软件CiteSpace绘制作者和机构图谱、关键词共现知识图谱、突现词时序图,并进行分析解读。结果显示共纳入文献3 725篇,其中高频关键词为"影响因素""危险因素""老年人""艾滋病""流行病学"等,核心研究主题主要涉及"农村居民健康危险因素""空气污染卫生问题对老年人疾病的影响""慢性病治疗满意度"等十大类,"细胞凋亡""医务人员""基因多态性"等是近5年来陆续兴起的研究热点,结果表明研究领域内部分作者间有密切合作,但总体较分散;卫生应急能力、居民健康水平、医疗资源配置是研究前沿趋势。  相似文献   

3.
为了分析水资源生态足迹的研究现状和热点趋势,本文以中国知网(CNKI)和web of science数据库为数据源,运用CiteSpace可视化分析软件,对2005—2020年水资源生态足迹领域中文和英文论文的发展现状和研究热点进行分析。前者包括发文数量、文献来源、研究机构、作者、地域合作网络和高被引文献等,后者包括关键词聚类分析和热点突现词分析等。常规参数分析结果表明:关于水资源生态足迹的研究,中文文献早于英文文献,二者发文量总体上都呈现上升趋势,是目前研究的热点领域;大部分中英文文献来源于领域内核心期刊,主要涉及环境和生态等领域;中文文献的研究机构合作网络较分散,而英文文献的研究机构合作关系更为密切;中文文献的研究者较多,形成相对明显的合作子群,而英文文献发文者较少且以中国学者居多;中国、美国和荷兰等国家是文献发表的主要力量。在热点突现词分析中,生态足迹的突现强度最高,表明水资源生态足迹研究进入成熟阶段。未来应加强水资源生态足迹领域的研究深度与广度,实现多学科交叉融合。  相似文献   

4.
为客观掌握城市公共安全领域的研究现状及发展趋势,采用高级检索方式对中国知网(CNKI)数据库中2001—2020年城市公共安全领域的核心文献进行检索;运用文献计量学对国内该领域相关文献的发表年份和发文数量、作者分布、研究机构、发文期刊以及高被引文献等进行统计分析;利用CiteSpace软件探究国内城市公共安全领域研究文献的关键词及发展阶段.结果表明:金磊、曲宗希、董华等是该领域的核心著者;兰州大学、中国人民公安大学、中国矿业大学以及中南大学为城市公共安全研究领域较为活跃的研究院校;《中国公共安全(综合版)》《中国安防》《上海城市管理职业技术学院学报》发文量较多;该领域的研究热点主要围绕公共安全网、智慧城市建设、城市风险清单等关键词展开;该领域经历了起步探索、发展强化至深化研究三个阶段.由此可知,该领域未来的研究趋势将集中于公共安全卫生、监管系统等方向.  相似文献   

5.
基于科学计量学方法,对国内区域创新的文献运用科学知识图谱分析工具Citespace进行分析研究,文献数据来源CNKI,并运用普赖斯曲线方程验证本文使用的数据满足"查全率"的要求。基于29年间CNKI数据库中关于区域创新的文献,从关键词共线分析、作者和机构合作分析、聚类分析及突变词检测等方面对国内区域创新的研究力量、研究热点、演化发展脉络和研究前沿等进行研究。  相似文献   

6.
在介绍《新闻学与传播研究》概况的基础上,从期刊不同阶段的载文特点、主要发文机构、高产作者、论文合著、研究热点的持续与漂移情况、热点关键词、共词网络等方面,统计分析了《新闻学与传播研究》期刊2006—2010年载文的文献计量学特征。  相似文献   

7.
刘锐  龚志起  杨娜  伍芮 《科技促进发展》2021,17(8):1478-1486
为全面了解国际生命周期社会影响评价(Social Life Cycle Assessment,S-LCA)的研究进展,探索其研究热点及趋势。选取Web Of Science的S-LCA领域文献,利用文献计量方法和文献可视化分析软件,对样本文献的研究国家和机构、作者合作、研究热点及趋势等方面进行分析。结果表明,S-LCA领域的发文量整体呈现出稳定增长的态势,发文集中分布于少数几个期刊,且期刊整体质量较高。国与国、机构与机构间的科研合作并不紧密,但在同一机构或相近地区,以发文量较多的作者为核心形成了作者合作网络群。通过对S-LCA领域的关键词共现和突发性检测分析,可以发现未来S-LCA领域研究的热点与前沿是将着重于指标体系的统一与完善、多元化的模型开发、实际应用及为政府、企事业单位等的决策提供参考性建议等方面的持续努力。  相似文献   

8.
周丽媛 《天津科技》2022,(4):7-11,15
以中国知网数据库为数据源,以"高校图书馆"和"阅读推广"为主题检索词进行高级检索,使用文献可视化分析软件(CiteSpace)进行数据分析,绘制作者合作图谱、机构合作图谱、关键词图谱、关键词时间线图谱,对高校图书馆阅读推广的研究现状、热点进行分析研究总结,并从人才培养、机构合作、投入机制、服务方式4个层面予以综述展望,...  相似文献   

9.
以中国期刊全文数据库为文献来源,运用文献计量学方法,从年代分布、期刊分布、核心作者分布、论文产出机构及研究主题等方面进行统计分析,揭示了目前科技档案国内研究现状,并利用聚类分析和多维尺度分析等多元统计分析方法,以高频关键词的共词矩阵为基础,初步绘制了我国科技档案研究知识图谱,得出其主要研究范围、研究热点等。  相似文献   

10.
目的:分析我国就业力高被引文献的计量特征。方法:检索中国学术期刊全文数据库(CNKI)1979—2013年的就业力文献,参照普赖斯定律确定高被引文献,用Excel 2007统计分析被引、年份、期刊、作者、单位、关键词、基金。结果:检出高被引文献267篇,分别被引16~441次,累计被引10123次,篇均被引37.91次;文献数自2001年逐年增至2007年达峰值53篇,之后整体缓慢下降;文献分布在153种期刊,其中《中国大学生就业》《教育发展研究》《中国青年政治学院学报》依次居文献数、总被引频次、篇均被引频次首位;文献作者共384人、署名413人次,独撰占61.80%,总合作率38.20%;作者机构187个,其中各类院校占91.45%,15个核心发文机构均为高校;涉及关键词567个,篇均关键词4.48个,“就业能力”“大学生”“就业”“大学生就业”“就业竞争力”的使用频次居前5位;78篇文献获基金101项次,其中部省级基金占63.27%,省级以上基金中社科类和教育类基金占79.22%。结论:就业力文献呈现以大学生为主要对象、以高校教师为核心作者、以省部级社科类和教育类基金为主要资助的特征,尚未形成权威期刊、拔尖作者、优秀团队、核心机构、集中关键词、跨国合作与基金支持,未来就业力研究文献将保持增长势头。  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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