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Two new integrable couplings of the soliton hierarchies with self-consistent sources 被引量:7
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作者 夏铁成 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期49-56,共8页
A kind of integrable coupling of soliton equations hierarchy with self-consistent sources associated with s/(4) has been presented (Yu F J and Li L 2009 Appl. Math. Comput. 207 171; Yu F J 2008 Phys. Lett. A 372 6... A kind of integrable coupling of soliton equations hierarchy with self-consistent sources associated with s/(4) has been presented (Yu F J and Li L 2009 Appl. Math. Comput. 207 171; Yu F J 2008 Phys. Lett. A 372 6613). Based on this method, we construct two integrable couplings of the soliton hierarchy with self-consistent sources by using the loop algebra sl(4). In this paper, we also point out that there are some errors in these references and we have corrected these errors and set up new formula. The method can be generalized to other soliton hierarchy with self-consistent sources. 展开更多
关键词 TC hierarchy generalized Burgers hierarchy self-consistent sources integrable couplings loop algebra
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Nonlocal symmetries and negative hierarchies related to bilinear Bcklund transformation 被引量:2
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作者 胡晓瑞 陈勇 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期14-18,共5页
In this paper, nonlocal symmetries defined by bilinear Baacklund transformation for bilinear potential Kd V(p Kd V)equation are obtained. By introducing an auxiliary variable which just satisfies the Schwartzian for... In this paper, nonlocal symmetries defined by bilinear Baacklund transformation for bilinear potential Kd V(p Kd V)equation are obtained. By introducing an auxiliary variable which just satisfies the Schwartzian form of Kd V(SKd V)equation, the nonlocal symmetry is localized and the Levi transformation is presented. Besides, based on three different types of nonlocal symmetries for potential Kd V equation, three sets of negative p Kd V hierarchies along with their bilinear forms are constructed. An impressive result is that the coefficients of the third type of(bilinear) negative p Kd V hierarchy(N 〉 0) are variable, which are obtained via introducing an arbitrary parameter by considering the translation invariance of the p Kd V equation. 展开更多
关键词 nonlocal symmetry bilinear Backlund transformation finite transformation negative hierarchy
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Schroedinger Flows to Symmetric Spaces and the Second Matrix-AKNS Hierarchies 被引量:2
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作者 CHEN Bing-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期653-656,共4页
This article gives a unified geometric interpretation of the second Matrix-AKNS hierarchies via Schroedinger flows to symmetric spaces of Kaehler and paraKaehler types.
关键词 AKNS hierarchy nonlinear Schrodinger equation Schrodinger flow
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RIEMANN-HILBERT PROBLEMS AND SOLITON SOLUTIONS OF NONLOCAL REVERSE-TIME NLS HIERARCHIES 被引量:1
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作者 Wenxiu MA 《Acta Mathematica Scientia》 SCIE CSCD 2022年第1期127-140,共14页
The paper aims at establishing Riemann-Hilbert problems and presenting soliton solutions for nonlocal reverse-time nonlinear Schrodinger(NLS) hierarchies associated with higher-order matrix spectral problems.The Sokho... The paper aims at establishing Riemann-Hilbert problems and presenting soliton solutions for nonlocal reverse-time nonlinear Schrodinger(NLS) hierarchies associated with higher-order matrix spectral problems.The Sokhotski-Plemelj formula is used to transform the Riemann-Hilbert problems into Gelfand-Levitan-Marchenko type integral equations.A new formulation of solutions to special Riemann-Hilbert problems with the identity jump matrix,corresponding to the reflectionless inverse scattering transforms,is proposed and applied to construction of soliton solutions to each system in the considered nonlocal reversetime NLS hierarchies. 展开更多
关键词 matrix spectral problem nonlocal reverse-time integrable equation integrable hierarchy Riemann-Hilbert problem inverse scattering transform soliton solution
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Two New Multi-component BKP Hierarchies 被引量:1
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作者 WU Hong-Xia LIU Xiao-Jun ZENG Yun-Bo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期193-199,共7页
We firstly propose two kinds of new multi-component BKP (mcBKP) hierarchy based on the eigenfunction symmetry reduction and nonstandard reduction, respectively. The first one contains two types of BKP equation with ... We firstly propose two kinds of new multi-component BKP (mcBKP) hierarchy based on the eigenfunction symmetry reduction and nonstandard reduction, respectively. The first one contains two types of BKP equation with self-consistent sources whose Lax representations are presented. The two mcBKP hierarchies both admit reductions to the k-constrained BKP hierarchy and to integrable (1+1)-dimensional hierarchy with self-consistent sources, which include two types of SK equation with self-consistent sources and of hi-directional SK equations with self-consistent 展开更多
关键词 multi-component BKP hierarchy BKP equation with self-consistent sources κ-constrained BKPhierarchy n-reduction of mcBKP Lax representation
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Factors influencing the establishment of dominance hierarchies of the grey triggerfish Balistes capriscus
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作者 David W.CLEVELAND Kari L.LAVALLI 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第1期18-35,共18页
Unlike other balistids, grey triggerfish Balistes capriscus occur in social groups in subtropical reef assemblages and have been noted to cooperate in capturing large crustacean prey. The objective of this study were ... Unlike other balistids, grey triggerfish Balistes capriscus occur in social groups in subtropical reef assemblages and have been noted to cooperate in capturing large crustacean prey. The objective of this study were to determine the structure of dominance hierarchies of these social groups and the factors that influence hierarchies of wild-caught grey triggerfish in a natu- ralistic setting. From observations of four groups of triggerfish (n = 19 fish) in both dyad and group (4 - 5 fish) settings, we provide a description of triggerfish behaviors and coloration patterns and an explanation of the social context in which suites of behaviors are used by dominant, middle-ranking, and subordinate fish. Sixteen behaviors and nine coloration patterns were noted for grey triggerfish. Grey triggerfish groups form linear hierarchies in both dyads and groups as measured by Landau's lndex of Linearity (h = 1.0 for Groups 1, 3, and 4 and h = 0.95 for Group 2 in dyads; h = 1.0 for all groups in group settings). Dyadic hierarchies, however, were not necessarily good predictors of the hierarchies found in larger group settings, as they only predicted two of the four group hierarchies. Sex played no role in influencing status or behavior. Size had the greatest influence on domi- nance status, with larger fish being more dominant than smaller fish. An individual's dominance ranking influenced both body coloration and posture. These results suggest that color patterns and body postures may also be used by observers as an indicator of an individual's social status in groups [Current Zoology 56 (1): 18-35, 2010]. 展开更多
关键词 Grey triggerfish Balistes capriscus Balistids Dominance hierarchies STATUS RANK BEHAVIOR
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Isospectral and Nonisospectral Lattice Hierarchies Associated with a Discrete Spectral Problem and Their Infinitely Many Conservation Laws
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作者 罗琳 范恩贵 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期17-20,共4页
In this paper, based on the discrete zero curvature representation, isospectrai and nonisospectrai lattice hierarchies are proposed. By means of solving corresponding discrete spectral equations, we demonstrate the ex... In this paper, based on the discrete zero curvature representation, isospectrai and nonisospectrai lattice hierarchies are proposed. By means of solving corresponding discrete spectral equations, we demonstrate the existence of infinitely many conservation laws for this two hierarchies and obtain the formulae of the corresponding conserved densities and associated fluxes. 展开更多
关键词 lattice hierarchy conservation laws discrete spectral problem
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A New Lie Algebra and Its Related Liouville Integrable Hierarchies
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作者 王惠 王新赠 +1 位作者 刘国栋 杨记明 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期407-411,共5页
A new Lie algebra G and its two types of loop algebras G1 and G2 are constructed. Basing on G1 and G2, two different isospectral problems are designed, furthermore, two Liouville integrable soliton hierarchies are obt... A new Lie algebra G and its two types of loop algebras G1 and G2 are constructed. Basing on G1 and G2, two different isospectral problems are designed, furthermore, two Liouville integrable soliton hierarchies are obtained respectively under the framework of zero curvature equation, which is derived from the compatibility of the isospectral problems expressed by Hirota operators. At the same time, we obtain the Hamiltonian structure of the first hierarchy and the bi-Hamiltonian structure of the second one with the help of the quadratic-form identity. 展开更多
关键词 Lie algebra Liouville integrable hierarchy Hirota operator Quadratic-form identity
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A Note on Standard Goal Programming with Fuzzy Hierarchies: A Sequential Approach
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作者 Maged George Iskander 《American Journal of Operations Research》 2016年第1期71-74,共4页
In the paper [Standard goal programming with fuzzy hierarchies: a sequential approach, Soft Computing, First online: 22 March 2015], it has been assumed that the normalized deviations should lie between zero and one. ... In the paper [Standard goal programming with fuzzy hierarchies: a sequential approach, Soft Computing, First online: 22 March 2015], it has been assumed that the normalized deviations should lie between zero and one. In some cases, this assumption may not be valid. Therefore, additional constraints must be incorporated into the model to ensure that the normalized deviations should not exceed one. This modification is illustrated by the given numerical example. 展开更多
关键词 Fuzzy Goal Programming Imprecise Hierarchy Normalized Deviations
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Integrating Levels of Hierarchical Organization in Porous Organic Molecular Materials
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作者 Jesus Ferrando‑Soria Antonio Fernandez 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期134-153,共20页
Porous organic molecular materials(POMMs)are an emergent class of molecular-based materials characterized by the formation of extended porous frameworks,mainly held by non-covalent interactions.POMMs represent a varie... Porous organic molecular materials(POMMs)are an emergent class of molecular-based materials characterized by the formation of extended porous frameworks,mainly held by non-covalent interactions.POMMs represent a variety of chemical families,such as hydrogen-bonded organic frameworks,porous organic salts,porous organic cages,C-H···πmicroporous crystals,supramolecular organic frameworks,π-organic frameworks,halogen-bonded organic framework,and intrinsically porous molecular materials.In some porous materials such as zeolites and metal organic frameworks,the integration of multiscale has been adopted to build materials with multifunctionality and optimized properties.Therefore,considering the significant role of hierarchy in porous materials and the growing importance of POMMs in the realm of synthetic porous materials,we consider it appropriate to dedicate for the first time a critical review covering both topics.Herein,we will provide a summary of literature examples showcasing hierarchical POMMs,with a focus on their main synthetic approaches,applications,and the advantages brought forth by introducing hierarchy. 展开更多
关键词 Porous organic molecular materials HIERARCHY Hydrogen-bonded organic frameworks Porous cages FULLERENE
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DEBRA: On the Unsupervised Learning of Concept Hierarchies from (Literary) Text
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作者 Peter J. Worth Domagoj Doresic 《International Journal of Intelligence Science》 2023年第4期81-130,共50页
With this work, we introduce a novel method for the unsupervised learning of conceptual hierarchies, or concept maps as they are sometimes called, which is aimed specifically for use with literary texts, as such disti... With this work, we introduce a novel method for the unsupervised learning of conceptual hierarchies, or concept maps as they are sometimes called, which is aimed specifically for use with literary texts, as such distinguishing itself from the majority of research literature on the topic which is primarily focused on building ontologies from a vast array of different types of data sources, both structured and unstructured, to support various forms of AI, in particular, the Semantic Web as envisioned by Tim Berners-Lee. We first elaborate on mutually informing disciplines of philosophy and computer science, or more specifically the relationship between metaphysics, epistemology, ontology, computing and AI, followed by a technically in-depth discussion of DEBRA, our dependency tree based concept hierarchy constructor, which as its name alludes to, constructs a conceptual map in the form of a directed graph which illustrates the concepts, their respective relations, and the implied ontological structure of the concepts as encoded in the text, decoded with standard Python NLP libraries such as spaCy and NLTK. With this work we hope to both augment the Knowledge Representation literature with opportunities for intellectual advancement in AI with more intuitive, less analytical, and well-known forms of knowledge representation from the cognitive science community, as well as open up new areas of research between Computer Science and the Humanities with respect to the application of the latest in NLP tools and techniques upon literature of cultural significance, shedding light on existing methods of computation with respect to documents in semantic space that effectively allows for, at the very least, the comparison and evolution of texts through time, using vector space math. 展开更多
关键词 Ontology Learning Ontology Engineering Concept hierarchies Concept Mapping Concept Maps Artificial Intelligence PHILOSOPHY Natural Language Processing Knowledge Representation Knowledge Representation and Reasoning Machine Learning Natural Language Processing NLP Computer Science Theoretical Computer Science EPISTEMOLOGY METAPHYSICS PHILOSOPHY Logic Computing Ontology First Order Logic Predicate Calculus
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Synthesis and Luminescence Property of Hierarchical Europium Oxalate Micropaticles
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作者 祝玮 张悠金 +1 位作者 何红梅 方智勇 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第1期65-69,I0003,I0004,共7页
Hierarchical europium oxalate Eu2(C2O4)3.10H2O micro-particles were synthesized through a simple precipitation method at room temperature in present of trisodium citrate. The products were characterized by X-ray dif... Hierarchical europium oxalate Eu2(C2O4)3.10H2O micro-particles were synthesized through a simple precipitation method at room temperature in present of trisodium citrate. The products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and photoluminescence. The possible formation mechanism of the hierarchical europium oxalate Eu2(C2O4)3.10H2O micro-particles was discussed. 展开更多
关键词 HIERARCHY Europium oxalate Precipitation method PHOTOLUMINESCENCE
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完整性视角下城市工业遗产价值评价研究
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作者 章早立 郑利军 《山西建筑》 2025年第2期12-15,27,共5页
从工业遗产完整性的角度出发,关注其历史、文化和科学技术价值等方面的评价与保护现状,强调了在保护工业遗产的过程中需注重整体工艺流程设备、建构筑物以及由工业发展延伸出的配套设施和非物质文化的保留,使用层次分析法、模糊综合评... 从工业遗产完整性的角度出发,关注其历史、文化和科学技术价值等方面的评价与保护现状,强调了在保护工业遗产的过程中需注重整体工艺流程设备、建构筑物以及由工业发展延伸出的配套设施和非物质文化的保留,使用层次分析法、模糊综合评价法构建评价体系对北京焦化厂工业遗存进行分级评价,通过定性与定量方法对完整性的各方面进行分析,并给出针对性建议,旨在为之后的工业遗产的价值评价与保护提供参考。 展开更多
关键词 完整性 工业遗产 北京焦化厂 价值评价 层次分析法
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全域旅游视角下县域旅游资源等级评价——以安陆市为例
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作者 李玲 张立明 谭本宇 《湖南工业大学学报》 2025年第2期70-77,共8页
针对全域旅游时代旅游资源的重新认定和等级评价问题,对全域旅游时代的旅游资源进行了再认识,应用层次分析法构建了全域旅游视角下县域旅游资源等级评价模型,对安陆市各旅游资源点进行了认定及等级评价。评价结果显示,全市有五级旅游资... 针对全域旅游时代旅游资源的重新认定和等级评价问题,对全域旅游时代的旅游资源进行了再认识,应用层次分析法构建了全域旅游视角下县域旅游资源等级评价模型,对安陆市各旅游资源点进行了认定及等级评价。评价结果显示,全市有五级旅游资源1处、四级旅游资源6处、三级旅游资源12处、二级旅游资源18处、一级旅游资源29处、未评级旅游资源23处,等级结构总体上呈“金字塔形”。针对该等级评价结果,提出了安陆市旅游资源开发的建议。 展开更多
关键词 全域旅游 旅游资源等级评价 层次分析法 安陆市
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未来社区健康场景服务质量评价指标体系构建研究
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作者 王文婷 王静 +2 位作者 周冯晨 刘克宁 汪胜 《中国全科医学》 CAS 北大核心 2025年第5期624-630,共7页
背景在国家推动“以治病为中心”向“以健康为中心”理念转变的背景下,浙江省率先打造面向全人群和全生命周期的未来社区健康场景,为基层卫生健康综合改革提供了“浙江样板”,构建一套科学有效的未来社区健康场景服务质量评价指标体系... 背景在国家推动“以治病为中心”向“以健康为中心”理念转变的背景下,浙江省率先打造面向全人群和全生命周期的未来社区健康场景,为基层卫生健康综合改革提供了“浙江样板”,构建一套科学有效的未来社区健康场景服务质量评价指标体系具有重要的理论意义和实践价值。目的构建浙江省未来社区健康场景服务质量评价指标体系,为提升社区健康服务能力和质量,推动人群健康目标实现提供参考。方法基于SERVQUAL理论模型,通过政策分析、文献研究和实地调研建立初始指标池;2023年10—12月,采用两轮德尔菲专家咨询法确定指标体系,并运用层次分析法确定各指标的权重和组合权重。结果两轮专家咨询均有17位专家参与,其中高级职称共12名(70.6%);工作年限≥10年15名(88.2%);未来社区的管理人员和医务人员共5名(29.4%)。两轮咨询专家积极性均为1.0,权威系数分别为0.862和0.842,协调程度逐轮提高,最终构建的指标体系包含5个一级指标、13个二级指标、36个三级指标。一级指标中,有形性、可靠性、保证性、响应性、移情性的权重分别为0.168、0.180、0.240、0.178、0.232;二级指标中,场地设施、数字化设备、服务提供、健康监测、服务效率、服务可及性、危机预防和应急救援能力、专业技能、活动组织、智能平台维护、服务态度和情感支持、服务效果、个性化服务的权重分别为0.399、0.601、0.672、0.328、0.487、0.171、0.342、0.410、0.416、0.174、0.284、0.323、0.393。结论本研究构建的浙江省未来社区健康场景服务质量评价指标体系科学可靠,具有较强的系统性、创新性、可操作性和应用价值,是开展未来社区健康场景评价的有效工具,希望能够为政府制定改进策略和相关政策提供参考。 展开更多
关键词 卫生服务研究 未来社区 服务质量评价 SERVQUAL理论模型 德尔菲法 层次分析法 指标体系
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Principal-subordinate hierarchical multi-objective programming model of initial water rights allocation 被引量:5
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作者 Dan WU Feng-ping WU Yan-ping CHEN 《Water Science and Engineering》 EI CAS 2009年第2期105-116,共12页
The principal-subordinate hierarchical multi-objective programming model of initial water rights allocation was developed based on the principle of coordinated and sustainable development of different regions and wate... The principal-subordinate hierarchical multi-objective programming model of initial water rights allocation was developed based on the principle of coordinated and sustainable development of different regions and water sectors within a basin. With the precondition of strictly controlling maximum emissions rights, initial water rights were allocated between the first and the second levels of the hierarchy in order to promote fair and coordinated development across different regions of the basin and coordinated and efficient water use across different water sectors, realize the maximum comprehensive benefits to the basin, promote the unity of quantity and quality of initial water rights allocation, and eliminate water conflict across different regions and water sectors. According to interactive decision-making theory, a principal-subordinate hierarchical interactive iterative algorithm based on the satisfaction degree was developed and used to solve the initial water rights allocation model. A case study verified the validity of the model. 展开更多
关键词 initial water rights allocation principal-subordinate hierarchy multi-objective programming model satisfaction degree
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The Hierarchical Order of Spaces in Arab Traditional Towns: The Case of Najd, Saudi Arabia 被引量:3
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作者 Mohammed Mashary Alnaim 《World Journal of Engineering and Technology》 2020年第3期347-366,共20页
The built environment faces many challenges in accommodating multi-cultural diversity and migrating from the suburbs, which led to different places being isolated or neglected. Sub-identities established by a specific... The built environment faces many challenges in accommodating multi-cultural diversity and migrating from the suburbs, which led to different places being isolated or neglected. Sub-identities established by a specific group of people become isolated and away from the shared identity that the built environment established for itself. We examine this issue in the Najdi </span><span style="font-family:Verdana;">built environment by examining how Najdi locals generated a holistic</span><span style="font-family:Verdana;"> hierarchical order of specs. This paper argues that the spatial order encouraged locals to develop a shared and agreed mechanism while in parallel, it gave individuals the ability to modify their places without affecting that shared holistic spatial order. 展开更多
关键词 HIERARCHY Order Space Built Environment Najd Urban Fabric CULTURE Space Syntax
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A Model of Hierarchical Key Assignment Scheme 被引量:1
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作者 ZHANG Zhigang ZHAO Jing XU Maozhi 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1597-1600,共4页
A model of the hierarchical key assignment scheme is approached in this paper, which can be used with any cryptography algorithm. Besides, the optimal dynamic control property of a hierarchical key assignment scheme w... A model of the hierarchical key assignment scheme is approached in this paper, which can be used with any cryptography algorithm. Besides, the optimal dynamic control property of a hierarchical key assignment scheme will be defined in this paper. Also, our scheme model will meet this property. 展开更多
关键词 user hierarchy access control key assignment CRYPTOGRAPHY multilevel data security
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Polymeric Liquid Templating of Hierarchical Porous Films by Nanofibrillar Alginic Acid Assemblies 被引量:1
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作者 Thai-Hoa Tran Sy-Thang Ho Thanh-Dinh Nguyen 《Soft Nanoscience Letters》 2014年第1期6-14,共9页
Hierarchical phases of the biomaterials can be used as template to transfer their intricate organization into biomimic inorganic solids. Herein, hierarchical mesoporous silica films with aligned pores have been templa... Hierarchical phases of the biomaterials can be used as template to transfer their intricate organization into biomimic inorganic solids. Herein, hierarchical mesoporous silica films with aligned pores have been templated by nanofibrillar alginic acid. An aqueous suspension of the alginic acid nanofibers was prepared by treating the brown seaweeds with sodium carbonate solution and subsequent precipitation in dilute hydrochloric acid. The alginic acid nanofibers of the organize into a hierarchical aligned phase in an acetic acid-sodium acetate buffer that was used to template silica-alginic acid composite films by evaporation induced self-assembly of alkoxysilane with nanofibrillar alginic acid. Calcination of the alginic acid template afforded hierarchical mesoporous silica glasses. Carbonization of the silica-alginic acid composites and subsequent etching the silica recovered mesoporous carbon supercapacitors. 展开更多
关键词 Nanofibrillar Alginic Acid hierarchial ORGANIZATION MESOPOROSITY SILICA Films Carbon SUPERCAPACITORS
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A Collaborative Simplification Method for Multiple Coastlines Based on the Hierarchical Triangulation Network Partition 被引量:6
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作者 Lihua ZHANG Lulu TANG +1 位作者 Shuaidong JIA Zeyuan DAI 《Journal of Geodesy and Geoinformation Science》 2020年第2期93-104,共12页
For the current automatic coastline generalization method,only one-line element is considered separately,but the relationship between the nearby elements is not effectively considered.A synergistic simplification meth... For the current automatic coastline generalization method,only one-line element is considered separately,but the relationship between the nearby elements is not effectively considered.A synergistic simplification method for multiple coastlines based on the hierarchical triangulation network partition(HTNP)is proposed in this paper.Firstly,the constrained Delaunay triangulation is constructed to partition the regions that can be simplified.Then,a hierarchical binary tree model to structure the morphological characteristics of the above several coastlines and the spatial proximity between different coastlines is constructed.Finally,the small curved and curved invisible parts of the coastline are deleted according to the visual constraints,and the narrow part between the coastline itself or the different coastlines is exaggerated appropriately,and the automatic simplification of the coastline is realized.The experimental results show that:①Relationships between the different coastlines are considered,and the shortcomings of considering the coastline separately are overcome;②Under the condition of the multiple coastlines in complex sea areas,the problem of collaborative simplification is solved,the quality of the coastlines are improved obviously,and the proposed method can be applied into more types of coastlines. 展开更多
关键词 cartographic generalization coastline simplification hierarchy relationship synergistic simplification
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