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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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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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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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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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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 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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NOVEL INTEGRABLE HAMILTONIAN HIERARCHIES WITH SIX POTENTIALS
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作者 Wenxiu MA 《Acta Mathematica Scientia》 SCIE 2024年第6期2498-2508,共11页
This paper aims to construct six-component integrable hierarchies from a kind of matrix spectral problems within the zero curvature formulation.Their Hamiltonian formulations are furnished by the trace identity,which ... This paper aims to construct six-component integrable hierarchies from a kind of matrix spectral problems within the zero curvature formulation.Their Hamiltonian formulations are furnished by the trace identity,which guarantee the commuting property of infinitely many symmetries and conserved Hamiltonian functionals.Illustrative examples of the resulting integrable equations of second and third orders are explicitly computed. 展开更多
关键词 matrix spectral problem zero curvature equation integrable hierarchy NLS equations mKdV equations
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Derivation of Expanded Isospectral-Nonisospectral Integrable Hierarchies via the Column-vector Loop Algebra
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作者 Hai-feng WANG Yu-feng ZHANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第3期778-800,共23页
A scheme for generating nonisospectral integrable hierarchies is introduced.Based on the method,we deduce a nonisospectral hierarchy of soliton equations by considering a linear spectral problem.It follows that the co... A scheme for generating nonisospectral integrable hierarchies is introduced.Based on the method,we deduce a nonisospectral hierarchy of soliton equations by considering a linear spectral problem.It follows that the corresponding expanded isospectral and nonisospectral integrable hierarchies are deduced based on a 6 dimensional complex linear space ■.By reducing these integrable hierarchies,we obtain the expanded isospectral and nonisospectral derivative nonlinear Schr?dinger equation.By using the trace identity,the biHamiltonian structure of these two hierarchies are also obtained.Moreover,some symmetries and conserved quantities of the resulting hierarchy are discussed. 展开更多
关键词 expanded isospectral-nonisospectral integrable hierarchies column-vector loop algebra bi-Hamiltonian structure SYMMETRY
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On limit fractional Volterra hierarchies
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作者 Lixiang Zhang Chuanzhong Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第1期7-16,共10页
For the limit fractional Volterra(LFV)hierarchy,we construct the n-fold Darboux transformation and the soliton solutions.Furthermore,we extend the LFV hierarchy to the noncommutative LFV(NCLFV)hierarchy,and construct ... For the limit fractional Volterra(LFV)hierarchy,we construct the n-fold Darboux transformation and the soliton solutions.Furthermore,we extend the LFV hierarchy to the noncommutative LFV(NCLFV)hierarchy,and construct the Darboux transformation expressed by quasi determinant of the noncommutative version.Meanwhile,we establish the relationship between new and old solutions of the NCLFV hierarchy.Finally,the quasi determinant solutions of the NCLFV hierarchy are obtained. 展开更多
关键词 limit fractional Volterra hierarchy noncommutative limit fractional Volterra hierarchy Darboux transformation soliton solution quasi determinant solution
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Squared Eigenfunction Symmetries for the BTL and CTL Hierarchies 被引量:1
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作者 程纪鹏 贺劲松 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第2期131-136,共6页
In this paper, the squared eigenfunction symmetries for the BTL and CTL hierarchies are expficitly constructed with the suitable modification of the ones for the TL hierarchy, by considering the BTL and GTL constraint... In this paper, the squared eigenfunction symmetries for the BTL and CTL hierarchies are expficitly constructed with the suitable modification of the ones for the TL hierarchy, by considering the BTL and GTL constraints. Also the connections with the corresponding additional symmetries are investigated: the squared eigenfunction symmetry generated by the wave function can be viewed as the generating function for the additional symmetries. 展开更多
关键词 squared eigenfunction symmetry the BTL and CTL hierarchies additional symmetries
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Witten's D_4 Integrable Hierarchies Conjecture 被引量:1
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作者 Huijun FAN Amanda FRANCIS +2 位作者 Tyler JARVIS Evan MERRELL Yongbin RUAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2016年第2期175-192,共18页
The authors prove that the total descendant potential functions of the theory of Fan-Jarvis-Ruan-Witten for D4 with symmetry group J and for D4T with symmetry group Gmax, respectively, are both tau-functions of the D4... The authors prove that the total descendant potential functions of the theory of Fan-Jarvis-Ruan-Witten for D4 with symmetry group J and for D4T with symmetry group Gmax, respectively, are both tau-functions of the D4 Kac-Wakimoto/Drinfeld-Sokolov hierarchy. This completes the proof, begun in the article by Fan-Jarvis-Ruan(2013), of the Witten Integrable Hierarchies Conjecture for all simple(ADE) singularities. 展开更多
关键词 Quantum cohomology Frobenius manifolds Singularity theory Integrable hierarchies
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Dual Hierarchies of a Multi-Component Camassa–Holm System
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作者 李红敏 李玉奇 陈勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第10期372-378,共7页
In this paper, we derive the bi-Hamiltonian structure of a multi-component Camassa–Holm system, which associates with the multi-component AKNS hierarchy and multi-component KN hierarchy via the tri-Hamiltonian dualit... In this paper, we derive the bi-Hamiltonian structure of a multi-component Camassa–Holm system, which associates with the multi-component AKNS hierarchy and multi-component KN hierarchy via the tri-Hamiltonian duality method. Furthermore, the spectral problems of the dual hierarchies may be obtained. 展开更多
关键词 bi-Hamiltonian STRUCTURE DUAL hierarchies Camasssa
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Polynomial-time Hierarchies on Some Classes of Functions (Ⅱ)
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作者 张立昂 《Science China Mathematics》 SCIE 1994年第9期1135-1143,共9页
This paper continues to study these hierarchies, the probably impossible relationships within and between them, and gives some complete functions for the classes.
关键词 computational complexity POLYNOMIAL-TIME hierarchies optimization PROBLEMS COUNTING PROBLEMS completeness.
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Polynomial-Time Hierarchies on Some Classes of Functions (Ⅰ)
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作者 张立昂 《Science China Mathematics》 SCIE 1994年第8期1018-1024,共7页
Four polynomial-time hierarchies on functions are introduced, which are considered to be generalizations of Valiant’s counting function class #P, class Span-P introduced by Kobler et al., Krentel’s optimization func... Four polynomial-time hierarchies on functions are introduced, which are considered to be generalizations of Valiant’s counting function class #P, class Span-P introduced by Kobler et al., Krentel’s optimization function class Opt-P, and F2p. It is shown that our polynomial hierarchies of optimization functions are the same as that defined by Krentel. The relationships within every hierarchy and between them are studied. 展开更多
关键词 computational COMPLEXITY COUNTING PROBLEMS optimization PROBLEMS POLYNOMIAL-TIME hierarchies.
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On the Problem of Optimizing Parallel Programs for Complex Memory Hierarchies
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作者 金国华 陈福接 《Journal of Computer Science & Technology》 SCIE EI CSCD 1994年第1期1-26,共26页
Based on a thorough study of the relationship between array element accesses and loop indices of the nested loop, a method is presented with which the staggering relation and the compacting relation between the thread... Based on a thorough study of the relationship between array element accesses and loop indices of the nested loop, a method is presented with which the staggering relation and the compacting relation between the threads of the nested loop (either with a single linear function or with multiple linear functions) can be determined at compile-time,and accordingly the nested loop (either perfectly nested one or imperfectly nested one)can be restructured to avoid the thrashing problem. Due to its simplicity, our method can be efficiently implemented in any parallel compiler, and the improvement of the performance is significant as shown by the experimental results. 展开更多
关键词 OPTIMIZATION parallel program complex memory hierarchies SRIS RSRIS compacted RSRIS
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The hierarchies of social epistemology and the essences of library system
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作者 ZHOU Wenjie 《Journal of Library Science in China》 2019年第1期136-137,共2页
Social Epistemology,initially developed by Jesse Hauk Shera and some other scholars,aims at providing a theoretical foundation for Library and Information Science(LIS).However,due to deficiencies in the follow-up rese... Social Epistemology,initially developed by Jesse Hauk Shera and some other scholars,aims at providing a theoretical foundation for Library and Information Science(LIS).However,due to deficiencies in the follow-up research,the relationship between professional activities of librarianship and the optimization of the different levels of social intelligence remain vague. 展开更多
关键词 hierarchies SOCIAL EPISTEMOLOGY
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