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1.
In this paper, we further investigate the consistency problem for the qualitative temporal calculus introduced by Pujari et al. [A.K. Pujari, G.V. Kumari, A. Sattar, INDU: An interval and duration network, in: Australian Joint Conference on Artificial Intelligence, 1999, pp. 291–303]. We prove the intractability of the consistency problem for the subset of pre-convex relations, and the tractability of strongly pre-convex relations. Furthermore, we also define another interesting set of relations for which the consistency problem can be decided by the -closure method, a method similar to the usual path-consistency method. Finally, we prove that the -closure method is also complete for the set of atomic relations of implying that the intervals have the same duration.  相似文献   

2.
Action logic of Pratt [21] can be presented as Full Lambek Calculus FL [14, 17] enriched with Kleene star *; it is equivalent to the equational theory of residuated Kleene algebras (lattices). Some results on axiom systems, complexity and models of this logic were obtained in [4, 3, 18]. Here we prove a stronger form of *-elimination for the logic of *-continuous action lattices and the –completeness of the equational theories of action lattices of subsets of a finite monoid and action lattices of binary relations on a finite universe. We also discuss possible applications in linguistics. Presented by Jacek Malinowski  相似文献   

3.
时点,时距和时序信息加工之间相关性研究   总被引:1,自引:0,他引:1  
王振勇  黄希庭 《心理科学》1999,22(5):398-402
本研究分为两个实验,分别采用预期式和回溯式范型,探讨时距、时序和时点三者之间信息加工的相关性,结果发现:同一时间经历,时距估计与时序判断随注意参与程度的增加,由负相关趋势向正相关变化;时距估计与时点离散度可能呈正相关趋势;时序判断与时点离散度随注意参与程度的增加,由负相关趋势向正相关变化。  相似文献   

4.
实验研究在2个月的时间内探索了回溯式时间记忆的特点,实验选取15个影视片断和8个新闻事件,影视片段播放的时间和新闻事件的发生同期,要求被试回忆影视片段和新闻事件的时点、时距和时序。结果表明:(1)在时序上,影视片段时序的准确性高于新闻事件;在时距上,7分钟和15分钟的准确性高于30分钟,7分钟时距倾向于高估,30分钟时距倾向于低估;在时点上,影视片段的准确性高于新闻事件。(2)时点的回溯式记忆受到被试自我卷入程度的影响。(3)回溯式时距估计受到真实时距的长短和延迟时间长短的交互影响。(4)事件序列关系一般倾向于具有网络层次的特征,在无充足思考时间条件下,倾向于具有线形模型的特征。  相似文献   

5.
It is known that for any subdirectly irreducible finite Heyting algebra A and any Heyting algebra B, A is embeddable into a quotient algebra of B, if and only if Jankov’s formula χ A for A is refuted in B. In this paper, we present an infinitary extension of the above theorem given by Jankov. More precisely, for any cardinal number κ, we present Jankov’s theorem for homomorphisms preserving infinite meets and joins, a class of subdirectly irreducible complete κ-Heyting algebras and κ-infinitary logic, where a κ-Heyting algebra is a Heyting algebra A with # ≥  κ and κ-infinitary logic is the infinitary logic such that for any set Θ of formulas with # Θ ≥  κ, ∨Θ and ∧Θ are well defined formulas.  相似文献   

6.
The Interpolation Theorem, first formulated and proved by W. Craig fifty years ago for predicate logic, has been extended to many other logical frameworks and is being applied in several areas of computer science. We give a short overview, and focus on the theory of software systems and modules. An algebra of theories TA is presented, with a nonstandard interpretation of the existential quantifier . In TA, the interpolation property of the underlying logic corresponds with the quantifier combination property . It is shown how the Modularization Theorem, the Factorization Lemma and the Normal Form Theorem for module expressions can be proved in TA. Dedicated to the 50th anniversary of William Craig’s Interpolation Theorem.  相似文献   

7.
Klunder  Barbara 《Studia Logica》2000,65(1):113-136
The notion of a pseudo-interior algebra was introduced by Blok and Pigozzi in [BPIV]. We continue here our studies begun in [BK]. As a consequence of the representation theorem for pseudo-interior algebras given in [BK] we prove that the variety of all pseudo-interior algebras is generated by its finite members. This result together with Jónsson's Theorem for congruence distributive varieties provides a useful technique in the study of the lattice of varieties of pseudo-interior algebras.  相似文献   

8.
It has been recently shown [4] that the lattice effect algebras can be treated as a subvariety of the variety of so-called basic algebras. The open problem whether all subdirectly irreducible distributive lattice effect algebras are just subdirectly irreducible MV-chains and the horizontal sum of two 3-element chains is in the paper transferred into a more tractable one. We prove that modulo distributive lattice effect algebras, the variety generated by MV-algebras and is definable by three simple identities and the problem now is to check if these identities are satisfied by all distributive lattice effect algebras or not. Presented by Daniele Mundici  相似文献   

9.
We introduce Łukasiewicz-Moisil relation algebras, obtained by considering a relational dimension over Łukasiewicz-Moisil algebras. We prove some arithmetical properties, provide a characterization in terms of complex algebras, study the connection with relational Post algebras and characterize the simple structures and the matrix relation algebras.  相似文献   

10.
张永红  黄希庭 《心理科学》2005,28(4):775-779
采用事后回溯设计,考察了大学生公众时间回溯式记忆的特点。研究选取1995到2001年之间发生可辨别的新闻事件14项,要求被试对新闻事件的时序、时点和时距进行回忆。结果表明:(1)公众事件回溯式时点记忆的正确率随时间的远近发生变化,较远的时间回忆正确率低,而较近的时间回忆正确率较高,存在近因效应。(2)公众事件的回溯式时距估计受真实时距的影响,短时距容易被高估,长时距容易被低估。(3)公众事件的回溯式时序回忆存在近因效应和首因效应,被试对发生较远的事件总是倾向于估计得更远,对发生较近的事件也倾向于估计得较近。而对两者中间的事件的顺序估计较为混乱。(4)本实验研究的公众事件回溯式时间记忆符合时间的重构理论和分段综合模型。  相似文献   

11.
时间期待是指个体利用环境中的时间信息预测目标刺激何时出现的能力。相关的认知模型可以分为两类:一类侧重于解释时间期待的形成过程, 如痕迹条件反射模型、双加工模型、动态注意模型、时间定向理论等; 另一类侧重于解释时间期待的更新过程, 如策略模型和时间再定位模型等。不同类型的时间期待激活的脑区不同, 表明时间期待的产生和更新过程存在分离:期待的产生激活与运动有关的左侧脑区, 而期待的更新激活与控制有关的右侧脑区。  相似文献   

12.
多感觉整合的时间再校准   总被引:1,自引:0,他引:1  
跨通道刺激的时间同步性是多感觉整合的必要条件, 但是由于刺激物理传导与神经传导的差异, 它们在时间上并非完全匹配。时间再校准指大脑能够适应跨通道刺激间很短的时间延迟的现象, 反映了多感觉整合在时间维度上的可塑性, 表现为适应相继呈现的跨通道刺激后, 主观同时点向时间延迟方向的偏移。本文主要介绍了时间再校准的通道效应与潜在机制, 其初始加工阶段, 它与刺激内容加工的关系及主要的影响因素。今后的研究应当进一步探索时间再校准能否发生于早期加工阶段, 检验其认知过程是否具有双向性, 探讨空间选择性注意的作用, 并结合神经机制的研究, 从综合的视角进行更完善的理论建构。  相似文献   

13.
David Hobby 《Studia Logica》1996,56(1-2):151-183
Semi-DeMorgan algebras are a common generalization of DeMorgan algebras and pseudocomplemented distributive lattices. A duality for them is developed that builds on the Priestley duality for distributive lattices. This duality is then used in several applications. The subdirectly irreducible semi-DeMorgan algebras are characterized. A theory of partial diagrams is developed, where properties of algebras are tied to the omission of certain partial diagrams from their duals. This theory is then used to find and give axioms for the largest variety of semi-DeMorgan algebras with the congruence extension property.Semi-deMorgan algebras include demi-p-lattices, the topic of H. Gaitan's contribution to this special edition. D. Hobby's results were obtained independently.  相似文献   

14.
为了在语篇的层面上从浅层的语词加工和深层的情境加工两个角度考察时间参照加工的特点,采用单因素4水平重复测量实验设计,使用EyelinkⅡ型眼动仪比较了时间参照与时间转换的眼动指标。结果显示,时间词区:远参照与短时转换的眼动指标接近,近参照与长时转换的指标接近;关键事件区:远参照与长时转换的指标接近,近参照与短时转换的指标接近。结果表明时间参照表现出类似时间转换的特点,其特点与能否维系语篇的因果连贯性相关。  相似文献   

15.
王小英  杨海燕  王丽娟  石友梅 《心理科学》2006,29(5):1063-1067,1048
本研究在Friedman实验范式的基础上,增加了“系统教学”变量,探究教学与4~6岁儿童未来时间认知能力发展的关系。结果表明:(1)“教学”是影响儿童未来时序认知的主要因素;(2)“点估计策略”与“习俗时间单元概念策略”是两种主要时间认知策略;(3)儿童未来时间认知策略的发展遵循从感性直观到抽象概括的发展规律;(4)“教学”是影响其未来时间认知策略的主要因素;(5)4岁儿童已能区分未来事件的时距信息,且其未来时距认知具有分段性。  相似文献   

16.
本研究探讨了图式化程度即例子的概括化程度对解决代数文字题的影响。结果表明 :(1 )例子的表层类似性与目标问题具有一种格式塔的同型效应 ,容易解决“属性”一一对应的问题。 (2 )由例子表层类似性构成的图式化程度低 ,迁移的范围比较窄 ;由例子结构类似性构成的图式化程度高 ,适用的范围比较宽。 (3 )尽管增加了例子与目标问题的难度 ,由结构类似性形成的代数图式仍然可以比较容易地解决目标问题  相似文献   

17.
时间记忆层次网络模型的实验检验   总被引:4,自引:0,他引:4  
实验采用分类性实验材料,使被试在对词单项目加工时形成较清晰的群集,进而形成时间组块,目的在于对时间记忆层次网络进行直接检验。其中时序判断用反时间时和正确率两种反应指标,时距估计用再现和口头估计两种方法。结果发现,时间信息记忆既存在层次网络的特征,又存在线性结构的特征。  相似文献   

18.
Mark Reynolds 《Studia Logica》1996,57(2-3):279-302
We present an axiomatisation for the first-order temporal logic with connectives Until and Since over the class of all linear flows of time. Completeness of the axiom system is proved.We also add a few axioms to find a sound and complete axiomatisation for the first order temporal logic of Until and Since over rational numbers time.The author would like to thank Dov Gabbay and Ian Hodkinson for helpful discussions on this material. The work was supported by the U.K. Science and Engineering Research Council under the Metatem project (GR/F/28526).Presented by Dov Gabbay  相似文献   

19.
Gaitán  Hernando 《Studia Logica》2000,64(1):83-92
In this paper we describe the Priestley space of a quasi-Stone algebra and use it to show that the class of finite quasi-Stone algebras has the amalgamation property. We also describe the Priestley space of the free quasi-Stone algebra over a finite set. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

20.
Representations of monadic MV -algebra, the characterization of locally finite monadic MV -algebras, with axiomatization of them, definability of non-trivial monadic operators on finitely generated free MV -algebras are given. Moreover, it is shown that finitely generated m-relatively complete subalgebra of finitely generated free MV -algebra is projective.  相似文献   

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