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1.
Hierarchical classes: Model and data analysis   总被引:1,自引:0,他引:1  
A discrete, categorical model and a corresponding data-analysis method are presented for two-way two-mode (objects × attributes) data arrays with 0, 1 entries. The model contains the following two basic components: a set-theoretical formulation of the relations among objects and attributes; a Boolean decomposition of the matrix. The set-theoretical formulation defines a subset of the possible decompositions as consistent with it. A general method for graphically representing the set-theoretical decomposition is described. The data-analysis algorithm, dubbed HICLAS, aims at recovering the underlying structure in a data matrix by minimizing the discrepancies between the data and the recovered structure. HICLAS is evaluated with a simulation study and two empirical applications.This research was supported in part by a grant from the Belgian NSF (NFWO) to Paul De Boeck and in part by NSF Grant BNS-83-01027 to Seymour Rosenberg. We thank Iven Van Mechelen for clarifying several aspects of the Boolean algebraic formulation of the model and Phipps Arabie for his comments on an earlier draft.  相似文献   
2.
Quantum MV algebras   总被引:1,自引:0,他引:1  
We introduce the notion of quantum MV algebra (QMV algebra) as a generalization of MV algebras and we show that the class of all effects of any Hilbert space gives rise to an example of such a structure. We investigate some properties of QMV algebras and we prove that QMV algebras represent non-idempotent extensions of orthomodular lattices.I should like to thank Prof. M.L. Dalla Chiara and Dr. P. Minari for many interesting comments and remarks. Daniele Mundici  相似文献   
3.
This study examined different conceptual and operational definitions of problematic Internet use (PIU). 3 perspectives of PIU are described along with a meta‐analytic review (K = 112) conducted to explore the implications stemming from how PIU is measured. The results offer evidence to support the construct validity of measures developed from the impulse control disorder and relationship resource deficits traditions but raise questions about substance dependence measures of PIU. Additionally, there were small but noteworthy differences in the associations between PIU and key antecedents and outcomes that could be attributed to PIU measurement tradition. Suggestions for developing a more robust body of scholarship on PIU are offered.  相似文献   
4.
5.
We compare fork arrow logic, an extension of arrow logic, and its natural first-order counterpart (the correspondence language) and show that both have the same expressive power. Arrow logic is a modal logic for reasoning about arrow structures, its expressive power is limited to a bounded fragment of first-order logic. Fork arrow logic is obtained by adding to arrow logic the fork modality (related to parallelism and synchronization). As a result, fork arrow logic attains the expressive power of its first-order correspondence language, so both can express the same input–output behavior of processes.  相似文献   
6.
Given a variety we study the existence of a class such that S1 every A can be represented as a global subdirect product with factors in and S2 every non-trivial A is globally indecomposable. We show that the following varieties (and its subvarieties) have a class satisfying properties S1 and S2: p-algebras, distributive double p-algebras of a finite range, semisimple varieties of lattice expansions such that the simple members form a universal class (bounded distributive lattices, De Morgan algebras, etc) and arithmetical varieties in which the finitely subdirectly irreducible algebras form a universal class (f-rings, vector groups, Wajsberg algebras, discriminator varieties, Heyting algebras, etc). As an application we obtain results analogous to that of Nachbin saying that if every chain of prime filters of a bounded distributive lattice has at most length 1, then the lattice is Boolean.We wish to thank Lic. Alfredo Guerin and Dr. Daniel Penazzi for helping us with linguistics aspects. We are indebted to the referee for several helpful suggestions. We also wish to thank Professor Mick Adams for providing us with several reprints and useful e-mail information on the subject.Suported by CONICOR and SECyT (UNC).  相似文献   
7.
Across three experiments, we explore differences between relational categories—whose members share common relational patterns—and entity categories, whose members share common intrinsic properties. Specifically, we test the claim that relational concepts are more semantically mutable in context, and therefore less stable in memory, than entity concepts. We compared memory for entity nouns and relational nouns, tested either in the same context as at encoding or in a different context. We found that (a) participants show better recognition accuracy for entity nouns than for relational nouns, and (b) recognition of relational nouns is more impaired by a change in context than is recognition of entity nouns. We replicated these findings even when controlling for factors highly correlated with relationality, such as abstractness–concreteness. This suggests that the contextual mutability of relational concepts is due to the core semantic property of conveying relational structure and not simply to accompanying characteristics such as abstractness. We note parallels with the distinction between nouns and verbs and suggest implications for lexical and conceptual structure. Finally, we relate these patterns to proposals that a deep distinction exists between words with an essentially referential function and those with a predicate function.  相似文献   
8.
Two experiments tested the effect of co-occurrence of a target object with affective stimuli on automatic evaluation of the target when the relation between the target and the affective stimuli suggests that they have opposite valence. Participants learned about targets that ended an unpleasant noise or a pleasant music. The valence of such targets is opposite to the valence of the affective stimuli that co-occur with them. Participants reported preference for targets that ended noise over targets that ended music, but automatic evaluation measures revealed the opposite preference. This suggests that automatic evaluation is sensitive to co-occurrence between stimuli more than to the relation between the stimuli, and that relational information has a stronger influence on deliberate evaluation than on automatic evaluation. These conclusions support the associative-propositional evaluation model (Gawronski & Bodenhausen, 2006), and add evidence regarding the sensitivity of the evaluative-conditioning effect to relational information.  相似文献   
9.
The study used scene analogies to investigate two component processes of analogical thinking: resolution of semantic interference, which emerges when the proper mapping between analogically matching objects is incoherent with their categorical features (e.g., stereotypical functions), and goal-driven selection of the key relational structure, by directing attention to the most promising objects which constitute that structure among many other candidate objects. We manipulated interference by placing in corresponding scenes the objects from one category in different relational roles. Selection was loaded by including additional, relationally irrelevant objects in a scene. We also manipulated relational complexity and the presence of salient objects (people) in relations. Increased load on both interference resolution and selection decreased the accuracy of analogical mapping, but these factors did not interact. Moreover, the factors yielded opposite patterns of interaction with relational complexity. Finally, salience eased selection, but tended to negatively influence interference resolution. In summary, inference resolution and selection seem to constitute two relatively independent facets of cognitive control involved in analogical thinking. Selection may act before mapping occurs, while interference influences analogy making only if an interfering object takes part in mapping.  相似文献   
10.
Palma  Cândida  Santos  Raquel 《Studia Logica》2001,67(1):75-88
In this paper we use Hobby's duality for semi-De Morgan algebras, to characterize those algebras having only principal congruences in the classes of semi-De Morgan algebras, demi-pseudocomplemented lattices and almost pseudocomplemented lattices. This work extends some of the results reached by Beazer in [3] and [4].  相似文献   
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