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A Relation of the Noncommutative Parameters in Generalized Noncommutative Phase Space
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作者 林冰生 衡太骅 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期22-24,共3页
We introduce the deformed boson operators which satisfy a deformed boson algebra in some special types of generalized noncommutative phase space. Based on the deformed boson algebra, we construct coherent state repres... We introduce the deformed boson operators which satisfy a deformed boson algebra in some special types of generalized noncommutative phase space. Based on the deformed boson algebra, we construct coherent state representations. We calculate the variances of the coordinate operators on the coherent states and investigate the corresponding Heisenberg uncertainty relations. It is found that there are some restriction relations of the noncommutative parameters in these special types of noncommutative phase space. 展开更多
关键词 of on is in HAVE A relation of the Noncommutative Parameters in Generalized Noncommutative Phase space
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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 granular computing algebraic quotient space model quotient structure upper(lower) congruence relation
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Beyond Public Spaces: Shared Spaces in the Contemporary City
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作者 Giulia Setti 《Journal of Civil Engineering and Architecture》 2013年第7期833-840,共8页
The text aims to investigate the relevance of the concept of"public space" and the continuous variations which have changed its meaning. Going beyond the concept of public space, the author can understand the semant... The text aims to investigate the relevance of the concept of"public space" and the continuous variations which have changed its meaning. Going beyond the concept of public space, the author can understand the semantic boundaries of this definition: Today, relational spaces and shared spaces are the forms with which people can express the concept of public space. The gradual spread of new forms of communication has transformed the static view of public space in a more dynamic condition, the distinction between square, street, garden has lost its meaning leaving space to fragments and residues. Contemporary public spaces are defined, as the residual places that come from the abandonment of industries. The large mono-functional voids, which originate from industrial dismantlement, should be strategically reconsidered as new shared public spaces, where the integration between different functions leads to reactivate new forms of re-using of built space. 展开更多
关键词 Time-space relational spaces shared public spaces HYBRIDIZATION degrees of publicity.
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Busking in Durham:Relational Performance and Urban Ecology
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作者 Xu Feixuan 《全球城市研究(中英文)》 2023年第4期101-132,192,共33页
本文基于在英国达勒姆的观察和访谈,探讨了当地的街头艺人如何在表演中使用策略,与街道环境及行人互动。本研究探讨了街头表演吸引观众的技巧,他们如何理解和驾驭自己在社会中的边缘地位。本文结合生态学理论和参与式观察,认为街头艺人... 本文基于在英国达勒姆的观察和访谈,探讨了当地的街头艺人如何在表演中使用策略,与街道环境及行人互动。本研究探讨了街头表演吸引观众的技巧,他们如何理解和驾驭自己在社会中的边缘地位。本文结合生态学理论和参与式观察,认为街头艺人从事的不仅是一种表演,更是一种与环境密切相关的实践。本文解释了街头艺人如何适应城市街区,与陌生人建立联系和互动。此外,艺人有意与刻板印象保持距离,既不表现为乞讨,也不纯粹以营利为目的,而是为城市生活中增加活力和生机,让公众对其行业产生积极的看法。本文通过对街头艺人及其社会关系的关注,意在为街头表演研究增加个人和环境视角。 展开更多
关键词 卖艺 街头表演 城市生态学 关系性 公共空间
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An Evaluation of Crown Structure and Site Index to Determine Crown Closure in Eucalyptus urophylla × E. grandis Stands in Guangxi,China 被引量:2
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作者 陶玉华 Roger WILLIAMS +12 位作者 Carol BROWN 曹书阁 Rachael CRANE Raymond DUVAL Dani FLOWERS Jonathan FRANKO Rachel HEFFLINGER Jonathan JOO Anne MAURO Crista RIEDY Margaret SMYTH Shawn STONE 谭丽凤 《Agricultural Science & Technology》 CAS 2014年第6期1005-1011,共7页
Eucalyptus forests are grown in many parts of the world for their commercial value and use in construction projects. Density management becomes im- portant as a means to attain the management goals in these forests. C... Eucalyptus forests are grown in many parts of the world for their commercial value and use in construction projects. Density management becomes im- portant as a means to attain the management goals in these forests. Changes in canopy and tree crown structure were quantified for Eucalyptus urophylla x E. grandis forests at different ages to determine when canopy closure occurs and the onset of competition begins. Site index was developed for these forests to determine whether site quality affects the canopy structure. Site index had little effect in the forests sampled, with the forest canopy on the better sites becoming slightly more elongated. Based upon crown projection ratio and crown diameter: dbh (diameter at breast height) ratio, it appears that crown closure occurs by age 4 years in these forests. The age at which this occurs was also checked and verified with the evaluation of relative spacing, RS (the ratio of the mean distance between trees to the average dominant height of the stand). The RS value displayed a rapid decline until age 4 years, and then became relatively flat through age 21 years. The rapid height growth during the first 3 years with no change in density accounted for this rapid decrease. By age 4 years, reductions in the number of trees due to mortality began to have more of an influence on this value, resulting in a more gradual de- cline. The implications for management are discussed. 展开更多
关键词 Site index Crown structure Forest canopy Relative spacing Crownclosure
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Fixed Point Theorems in Relational Metric Spaces with an Application to Boundary Value Problems
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作者 PRASAD Gopi KHANTWAL Deepak 《Journal of Partial Differential Equations》 CSCD 2021年第1期83-93,共11页
In this paper,we establish fixed point theorems for generalized nonlinear contractive mappings using the concept of w-distance in relational metric spaces.Thus we generalize the recent results of Senapati and Dey[J.Fi... In this paper,we establish fixed point theorems for generalized nonlinear contractive mappings using the concept of w-distance in relational metric spaces.Thus we generalize the recent results of Senapati and Dey[J.Fixed Point Theory Appl.19,2945-2961(2017)]and many other important results relevant to this literature.In order to revel the usefulness of such investigations,an application to first order periodic boundary value problem are given.Moreover,we furnish a non-trivial example to demonstrate the validity of our generalization over previous existing results. 展开更多
关键词 Binary relation R-lower semi-continuity relational metric spaces
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Gravity observation at continental borderlands (Russia, Primorie, Cape Shults)
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作者 Vladimir Yu. Timofeev Eugenii N. Kalish +7 位作者 Dmitriy G. Ardyukov Maksim G. Valitov Anton V. Timofeev Yurii F. Stus Ruslan G. Kulinich Dmitrii A. Nosov Igor S. Sizikov Bernard Ducarme 《Geodesy and Geodynamics》 2017年第3期193-200,共8页
The paper is focused on different kinds of gravity results obtained in Shults Cape Observatory for 2010 -2015. Gravity observation is interpreted together with GPS observation data which was obtained from 2012 to 2015... The paper is focused on different kinds of gravity results obtained in Shults Cape Observatory for 2010 -2015. Gravity observation is interpreted together with GPS observation data which was obtained from 2012 to 2015 at the same station, The station is situated on Gamov peninsular (42.58° N, 131.15° E, Russia) at the coast of Japan Sea, This region constitutes the eastern boundary of Eurasia. This major continental tectonic feature is associated with a seismic activity, high heat flow and anomalous thickness of earth's crust. The goal of the observation was the investigation of gravity variation with time and seismicity situation monitoring. Gravity observation was developed at special basement by absolute gravimeter (GABL type) and by spring gravimeter (SCINREX CG-5and gPhone type). Tidal models were tested by results of observation with spring gravimeters. Reduction task was solved, as the experimental data received from different points of Shults Cape Observatory was used. Applied reduction coefficient is 203.3 12Gal m l, and agrees with theoretical calculation. Next goal was studying structure of earth's crust by means of gravity models. Gravity anomaly varied from 30 mGal to 46 mGal, which also depend on difference reference system, Experimental results were used for testing of the structure of continental boundary, which also depends on the sea bottom flexion. Thickness of elastic layer was estimated from 12 km to 18 km by using different models. 展开更多
关键词 Absolute and relative gravity observation space geodesy Reduction task for gravity Structure models Crust
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Review of space relative navigation based on angles-only measurements 被引量:7
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作者 Baichun Gong Sha Wang +1 位作者 Shuang Li Xianqiang Li 《Astrodynamics》 EI CSCD 2023年第2期131-152,共22页
Relative navigation is a key enabling technology for space missions such as on-orbit servicing and space situational awareness.Given that there are several special advantages of space relative navigation using angles-... Relative navigation is a key enabling technology for space missions such as on-orbit servicing and space situational awareness.Given that there are several special advantages of space relative navigation using angles-only measurements from passive optical sensors,angles-only relative navigation is considered as one of the best potential approaches in the field of space relative navigation.However,angles-only relative navigation is well-known for its range observability problem.To overcome this observability problem,many studies have been conducted over the past decades.In this study,we present a comprehensive review of state-of-the-art space relative navigation based on angles-only measurements.The emphasis is on the observability problem and solutions to angles-only relative navigation,where the review of the solutions is categorized into four classes based on the intrinsic principle:complicated dynamics approach,multi-line of sight(multi-LOS)approach,sensor offset center-of-mass approach,and orbit maneuver approach.Then,the fight demonstration results of angles-only relative navigation in the two projects are briefly reviewed.Finally,conclusions of this study and recommendations for further research are presented. 展开更多
关键词 space relative navigation relative orbit determination angles-only measurement OBSERVABILITY
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空间的社会性意涵与社会空间化理论探析
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作者 林聚任 《探索》 2024年第6期90-99,共10页
“空间问题”或“社会空间化”理论随着社会科学研究的“空间转向”,而越来越受到学者们的关注和重视。这一研究转向表明社会学家已锚定空间的社会性意涵,认识到了空间的社会学意义,超越了单纯把空间看作是社会行动或现象之外的“容器... “空间问题”或“社会空间化”理论随着社会科学研究的“空间转向”,而越来越受到学者们的关注和重视。这一研究转向表明社会学家已锚定空间的社会性意涵,认识到了空间的社会学意义,超越了单纯把空间看作是社会行动或现象之外的“容器”或外部背景的局限。在梳理关于空间的社会性认知和社会空间化理论的基础上,侧重阐述社会空间的基本属性与特征,强调从社会学视角分析社会空间问题时,不是关注“空间中的事物”,而是关注作为社会现象与过程的空间生产本身。当我们把空间要素纳入人们社会活动,从社会过程去加以界定认识,即可以新的视角重新认识社会现象、重新认识空间问题,从而获得“空间想象力”。因此,可从关系主义理论视角去分析社会空间问题,把社会空间看作一种关系性的社会存在物,具有其自身特征和规定性,即空间并不外在于社会过程,而是以关系的形式体现为社会行动和社会关系的广延性,这是其社会性意涵之根本所在。关系主义理论视角有助于深入认识空间的关系属性,更好地对社会空间关系及其社会意义做出解释。当前,我国面对构建中国自主哲学社会科学知识体系的新时代任务,应在系统探讨空间社会学基本理论和知识体系构建基础上,加强空间化理论分析意识,立足中国社会研究需要促进这一新学科领域的创新与发展。 展开更多
关键词 空间的社会性 社会空间化 关系主义空间论
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On the Space bv_p(F) of Sequences of p-bounded Variation of Fuzzy Numbers
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作者 zer TALO Feyzi BA■AR 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第7期1205-1212,共8页
Recently, the space bvp of real or complex numbers consisting of all sequences whose differences are in the space lp has been studied by Basar, Altay [Ukrainian Math. J. 55(1)(2003), 136-147], where 1 ≤ p ≤ ∞. ... Recently, the space bvp of real or complex numbers consisting of all sequences whose differences are in the space lp has been studied by Basar, Altay [Ukrainian Math. J. 55(1)(2003), 136-147], where 1 ≤ p ≤ ∞. The main purpose of the present paper is to introduce the space bvp(F) of sequences of p-bounded variation of fuzzy numbers. Moreover, it is proved that the space bvp(F) includes the space lp(F) and also shown that the spaces bvp(F) and lp(F) axe isomorphic for 1 ≤ p ≤∞. Furthermore, some inclusion relations have been given. 展开更多
关键词 sequence of fuzzy numbers space of difference sequences isomorphic spaces and inclusion relations
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罗维利的物理关系论思想
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作者 朱科夫 陈磊 马永革 《自然辩证法研究》 CSSCI 北大核心 2016年第8期90-95,共6页
在西方思想史上,时空关系论和时空实体论的争论不仅影响着古今众多哲学家,更对物理学领域的发展起着引导性的作用。通过考察和分析关系论的代表人物——当代物理学家卡尔罗·罗维利对物理关系论的评述,本文从广义相对论、量子力学... 在西方思想史上,时空关系论和时空实体论的争论不仅影响着古今众多哲学家,更对物理学领域的发展起着引导性的作用。通过考察和分析关系论的代表人物——当代物理学家卡尔罗·罗维利对物理关系论的评述,本文从广义相对论、量子力学和量子引力理论的不同角度探讨了在当代物理前沿基础理论视角下的关系论的内涵和意义。 展开更多
关键词 时空关系论 广义相对论 量子力学诠释 量子引力
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线性旅游目的地的概念框架与研究展望 被引量:1
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作者 杨效忠 李冬花 +1 位作者 黄剑锋 陆林 《地理学报》 EI CSSCI CSCD 北大核心 2023年第12期2939-2957,共19页
旅游目的地是旅游地理学的核心概念。旅游目的地空间形态、空间规模、空间关系的线性发展需要我们立足旅游地理学的学科视角,针对线性旅游目的地形成统一的概念界定,完善已有的旅游目的地认知体系。本文基于后结构主义的理论视角,构建... 旅游目的地是旅游地理学的核心概念。旅游目的地空间形态、空间规模、空间关系的线性发展需要我们立足旅游地理学的学科视角,针对线性旅游目的地形成统一的概念界定,完善已有的旅游目的地认知体系。本文基于后结构主义的理论视角,构建线性旅游目的地的概念框架与研究体系,以期建立完整的“理论指导实践、实践完善理论”的旅游目的地反馈机制。研究认为:①线性旅游目的地是以特定的自然、文化主题为引领,以旅游基础要素的线性延展为基础,以旅游者、旅游经营者、旅游产品、旅游信息、旅游服务等各类要素主体的流动关系为根本,形成的沿特定方向关联互动的目的地组织共同体与空间连续体,具备关联性、流动性、动态性的空间组织特征。②线性旅游目的地作为旅游目的地时空关系交替演化的结果,具备发生发展的演化过程,既包括时间维度上组织结构线性整合的过程演化,也包括空间维度上各类要素主体集聚扩散的空间优化。③后结构主义的关系思维与尺度认知为线性旅游目的地关系的建构、关系的流动、空间的生成以及尺度的转换等时空演化研究提供了综合性的认知框架,而线性旅游目的地概念框架与研究体系的确立,也推动了后结构主义向旅游地理学研究领域的理论拓展与实践延伸。 展开更多
关键词 线性旅游目的地 后结构主义 关系主义 关系空间 概念框架
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