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1.
Jiří Adámek 《Studia Logica》2004,78(1-2):7-33
Finitary quasivarieties are characterized categorically by the existence of colimits and of an abstractly finite, regularly projective regular generator G. Analogously, infinitary quasivarieties are characterized: one drops the assumption that G be abstractly finite. For (finitary) varieties the characterization is similar: the regular generator is assumed to be exactly projective, i.e., hom(G, –) is an exact functor. These results sharpen the classical characterization theorems of Lawvere, Isbell and other authors.Supported by the Czech Grant Agency (Project 201/02/0148).Special issue of Studia Logica: Algebraic Theory of Quasivarieties Presented by
M. E. Adams, K. V. Adaricheva, W. Dziobiak, and A. V. Kravchenko 相似文献
2.
We study the structure of algebraic -closed subsets of an algebraic lattice L, where is some Browerian binary relation on L, in the special case when the lattice of such subsets is an atomistic lattice. This gives an approach to investigate the atomistic lattices of congruence-Noetherian quasivarieties.V. A. Gorbunov has died in January 1999Special issue of Studia Logica: Algebraic Theory of Quasivarieties Presented by
M. E. Adams, W. Dziobiak, and A. V. Kravchenko 相似文献
3.
Let
be a finite collection of finite algebras of finite signature such that SP(
) has meet semi-distributive congruence lattices. We prove that there exists a finite collection
1 of finite algebras of the same signature,
, such that SP(
1) is finitely axiomatizable.We show also that if
, then SP(
1) is finitely axiomatizable. We offer new proofs of two important finite basis theorems of D. Pigozzi and R. Willard. Our actual results are somewhat more general than this abstract indicates.While working on this paper, the first author was partially supported by the Hungarian National Foundation for Scientific Research (OTKA) grant no. T37877 and the second author was supported by the US National Science Foundation grant no. DMS-0245622.Special issue of Studia Logica: Algebraic Theory of Quasivarieties Presented by
M. E. Adams, K. V. Adaricheva, W. Dziobiak, and A. V. Kravchenko 相似文献
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Relatively congruence regular quasivarieties and quasivarieties of logic have noticeable similarities. The paper provides a unifying framework for them which extends the Blok-Pigozzi theory of elementarily algebraizable (and protoalgebraic) deductive systems. In this extension there are two parameters: a set of terms and a variable. When the former is empty or consists of theorems, the Blok-Pigozzi theory is recovered, and the variable is redundant. On the other hand, a class of membership logics is obtained when the variable is the only element of the set of terms. For these systems the appropriate variant of equivalent algebraic semantics encompasses the relatively congruence regular quasivarieties. 相似文献
6.
Kirk R. Blankstein Gordon L. Flett Paul Boase Brenda B. Toner 《Anxiety, stress, and coping》2013,26(2):103-112
Abstract The primary purpose of the present study was to examine cognitive reactions of high and low test-anxious subjects while performing a task of extreme difficulty. A sample of 44 subjects (28 females, 16 males) attempted a difficult analogies task and then reported their thoughts during the task. Subjects also completed the Sarason Test Anxiety Scale and several other self-report measures of their cognitive reactions to the task. Thought listings were classified according to their referent (self, task, or unrelated) and their valence (positive, negative, or neutral). Correlational analyses were then performed with the various measures and revealed an association between test anxiety and reports of negative thoughts involving the self. Test anxiety was not related significantly to the number of thoughts involving the task nor to actual performance on the task. However, test-anxious subjects did report more negative expectancies for their performance and greater cognitive interference during the task. Negative self-expectancies were also related to more negative self thoughts, fewer positive self thoughts, and fewer positive task-related thoughts. The results are interpreted as further evidence for both the role of negative self-related cognitions in the experience of test anxiety and the usefulness of unstructured measures in anxiety research. 相似文献
7.
Spirituality is important to humans but gets little attention in experimental studies of life span cognitive development. One way to integrate such studies is to examine cognitive aspects of spiritual development using complex postformal Piagetian models. Four possible points of interface within postformal models are: developmental stages; elements of emotion and will; multiperson cognition; and forms taken by the processes used. Testable hypotheses are outlined and some possible difficulties to be expected within such research are discussed. 相似文献
8.
Adams and Dziobiak proved that any finite-to-finite universal quasivariety must be Q-universal, and then asked whether a somewhat weaker hypothesis could lead to the same conclusion. We show that their original hypothesis cannot be weakened to its naturally extreme form.To Professor Ale Pultr on his 65th birthdayThe authors gratefully acknowledge the support of the NSERC of Canada, of the project LN00A056 of the Czech Ministry of Education, and also of the Grant Agency of Czech Republic under the grant 201/02/0148.Special issue of Studia Logica: Algebraic Theory of Quasivarieties Presented by
M. E. Adams, K. V. Adaricheva, W. Dziobiak, and A. V. Kravchenko 相似文献
9.
We present a theory that copes with the dynamics of inconsistent information. A method is set forth to represent possibly inconsistent information by a finite state. Next, finite operations for expansion and contraction of finite states are given. No extra-logical element — a choice function or an ordering over (sets of) sentences — is presupposed in the definition of contraction. Moreover, expansion and contraction are each other's duals. AGM-style characterizations of these operations follow. 相似文献
10.
A confusion model is defined as a model that decomposes response probabilities in stimulus identification experiments into perceptual parameters and response parameters. Historically, confusion models fall into two groups. Models in Group I, which includes Townsend's (Perception and Psychophysics, 1971, 9, 40–50) overlap model, were developed on the basis of the notion that stimulus identification is mediated by a finite number of internal states. We call the general class of models that have this processing interpretation finite state confusion models. Models in Group II, which includes Luce's (R. O. Luce et al., Eds., Handbook of Mathematical Psychology (Vol. I), New York: Wiley, 1963) biased choice model, were not developed on the basis of an explicit processing interpretation. It is shown here that models in Group II are not finite state confusion models. We prove in addition that except for Falmagne's (Journal of Mathematical Psychology, 1972, 9, 206–224) simply biased model models in Group II belong to a certain class of infinite state confusion models, namely, models asserting that stimulus identification is mediated by a continuous space of vectors representing detector activation levels. 相似文献
11.
Linguistics, Logic and Finite Trees 总被引:3,自引:0,他引:3
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In this paper, we prove that Heyting's arithmetic can be interpreted in an intuitionistic version of Russell's Simple Theory of Types without extensionality. 相似文献
15.
Each year, thousands of pedestrians are killed or injured while crossing streets in the United States. Pedestrians who jaywalk across busy intersections increase their risk of being injured by an automobile. The present series of studies investigated pedestrian jaywalking behaviors under temporal conditions which appeared to control noncompliance and compliance with pedestrian walk signs. An intersection involving three major streets was the target site of the studies. The timing of walk and no-walk light sequences was different in the clockwise and counterclockwise direction and produced differential delays. In three separate studies, significantly more pedestrians jaywalked when walking in the long-delay as opposed to short-delay direction. Traffic planners might use these findings to establish safer pedestrian signal systems. 相似文献
16.
An identical-subject-repeated-measures design, involving two counterbalanced conditions, was employed to investigate adaptation when the presentation of a 100-word list is distributed and when it is massed. In Condition I, the entire list was read aloud during each of five successive trials. Since a specific word reoccurred only after all of the others were displayed, the presentation may be said to be distributed. In contrast, the Condition II presentation was massed. Only after a word was read five times was the next one presented. The results indicate that significant adaptation occurred in both conditions. However, adaptation plateaued in the distributed condition. This was not the case when massing was employed. The among-condition analyses revealed that significantly more adaptation occurred in the massed than in the distributed condition. 相似文献
17.
本研究运用2个行为实验探讨了复杂情境下自我决策、为他人决策和预期他人决策在无意识思维方式和有意识思维方式下的决策表现差异。实验1发现复杂情境中无意识思维方式下,自我决策和为他人决策的决策表现显著优于预期他人决策,自我决策和为他人决策表现没有显著差异。实验2发现复杂情境中有意识思维时,在陌生人条件下,为他人决策表现分数显著高于自我决策与预期他人决策,自我决策和预期他人决策表现无显著差异;在朋友条件下,为他人决策和预期他人决策的决策表现显著优于自我决策,为他人决策和预期他人决策表现无显著差异。研究结果支持了本文提出的决策视角-心理距离作用假设(the Perspective-Distance Effect Hypothesis,PDEH)。 相似文献
18.
医患双方对医患关系认知差异性的调查分析 总被引:16,自引:4,他引:16
采取整群随机抽样方法,现场调查发现,医患双方对医患关系重要性的认知一致,而对其性质、发展趋势、法律适用,以及医患冲突的主要诱因、责任主体、主要解决方式的认知状况均存在着显著性差异。相互理解、交流和尊重是建立和谐医患关系的根本措施。 相似文献
19.
Carl J. Dunst 《Journal of applied developmental psychology》1984,5(3):203-211
The visual attention behavior of 2- to 3-month-old infants was monitored as part of their participation in an operant conditioning study. Attention was monitored under three conditions: a baseline condition where a visual target remained stationary; a baseline conditioning where the target was made to move on an aperiodic, response-independent schedule; and a conditioning phase where the target was operantly under the control of the subjects. Fixation time differed significantly as a function of experimental condition, with the response-contingent condition producing the greatest amount of fixation and the stabile, baseline condition producing the least amount of fixation. The implications of the findings for intervention purposes are discussed. 相似文献
20.
该文受戴维森的启发,并基于唯特根斯坦对“把…看作…”的分析,尝试提出隐喻创造相似性的工作机制以及这一机制运作如何可能的恰当件条件,并将笔者的这一理论与哈雷等提出的语义学—本体论分析进行了比较。 相似文献