Partial residuated structures and quantum structures

Residuated structures, bounded commutative residuated lattices in particular, play an important role in the study of algebraic structures of logics—classical and non-classical. In this paper, by introducing partial adjoint pairs, a new structure is presented, named partial residuated lattices, which can be regarded as a version of residuated lattices in the case of partial operations, and their basic properties are investigated. The relations between partial residuated lattices and certain quantum structures are considered. We show that lattice effect algebras and D-lattices both are partial residuated lattices. Conversely, under certain conditions partial residuated lattices are both lattice effect algebras and D-lattices. Finally, dropping the assumption on commutativity, some similar results are obtained. Project supported by the NSF of China (No. 10771524).     

Quotients and weakly algebraic sets in pseudoeffect algebras

In the paper, we show that the quotient [E]_I[E]_I of a lattice-ordered pseudoeffect algebra EE with respect to a normal weak Riesz ideal II is linearly ordered if and only if II is a prime normal weak Riesz ideal, and [E]_I[E]_I is a representable pseudo MV-algebra if and only if II is an intersection of prime normal weak Riesz ideals. Moreover, we introduce the concept of weakly algebraic sets in pseudoeffect algebras, discuss the characterizations of weakly algebraic sets and show that weakly algebraic sets in pseudoeffect algebra EE are in a one-to-one correspondence with normal weak Riesz ideals in pseudoeffect algebra E.E.     

Pseudo-BCK algebras as partial algebras

It is well-known that the representation of several classes of residuated lattices involves lattice-ordered groups. An often applicable method to determine the representing group (or groups) from a residuated lattice is based on partial algebras: the monoidal operation is restricted to those pairs that fulfil a certain extremality condition, and else left undefined. The subsequent construction applied to the partial algebra is easy, transparent, and leads directly to the structure needed for representation.In this paper, we consider subreducts of residuated lattices, the monoidal and the meet operation being dropped: the resulting algebras are pseudo-BCK semilattices. Assuming divisibility, we can pass on to partial algebras also in this case. To reconstruct the underlying group structure from this partial algebra, if applicable, is again straightforward. We demonstrate the elegance of this method for two classes of pseudo-BCK semilattices: semilinear divisible pseudo-BCK algebras and cone algebras.     

Effect algebras are conditionally residuated structures

The aim of the paper was to link up the structures used in foundations of quantum logic and that arising in many-valued reasoning. It is shown that effect algebras and pseudoeffect algebras can be described as conditionally residuated structures.     

Are basic algebras residuated structures?

MV-algebras are bounded commutative integral residuated lattices satisfying the double negation and the divisibility laws. Basic algebras were introduced as a certain generalization of MV-algebras (where associativity and commutativity of the binary operation is neglected). Hence, there is a natural question if also basic algebras can be considered as residuated lattices. We prove that for commutative basic algebras it is the case and for non-commutative ones we involve a modified adjointness condition which gives rise a new generalization of a residuated lattice.     

可换双剩余格上的广义模糊粗糙集及其公理化

双剩余格是t-模、t-余模、模糊剩余蕴涵及其对偶算子的代数抽象,基于格的L-模糊关系是普通模糊关系的推广。作为Pawlak经典粗糙集及多种模糊粗糙集模型的共同推广,提出了一种基于可换双剩余格及L-模糊关系的广义模糊粗糙集模型,引入了正则可换双剩余格的概念,并给出了基于正则可换双剩余格的广义模糊粗糙上、下近似算子的公理系统,推广了多个文献中已有的结果。     

Riesz ideals in generalized pseudo effect algebras and in their unitizations

We prove that there is an order isomorphism between the lattice of all normal Riesz ideals and the lattice of all Riesz congruences in upwards directed generalized pseudoeffect algebras (or GPEAs, for short). We give a sufficient and necessary condition under which a normal Riesz ideal I of a weak commutative generalized pseudoeffect algebra P is a normal Riesz ideal also in the unitization [^(P)]\widehat{P} of P. These results extend those obtained recently by Avalllone, Vitolo, Pulmannová and Vinceková for effect algebras. At the same time, we give the conditions under which the quotient of a generalized pseudoeffect algebra P is a generalized effect algebra and linearly ordered generalized pseudoeffect algebra.     

On the algebraic structure of binary lattice-valued fuzzy relations

From a general algebraic point of view, this paper aims at providing an algebraic analysis for binary lattice-valued relations based on lattice implication algebras—a kind of lattice-valued propositional logical algebra. By abstracting away from the concrete lattice-valued relations and the operations on them, such as composition and converse, the notion of lattice-valued relation algebra is introduced, LRA for short. The reduct of an LRA is a lattice implication algebra. Such an algebra generalizes Boolean relation algebras by general distributive lattices and can provide a fundamental algebraic theory for establishing lattice-valued first-order logic. Some important results are generalized from the classical case. The notion of cylindric filter is introduced and the generated cylindric filters are characterized.     

粗代数研究

在粗糙集的代数方法研究中,一个重要的方面是从粗糙集的偶序对((下近似集,上近似集()表示入手,通过定义偶序对的基本运算,从而构造出相应粗代数,并寻找能够抽象刻画偶序对性质的一般代数结构.其中最有影响的粗代数分别是粗双Stone代数、粗Nelson代数和近似空间代数,它们对应的一般代数结构分别是正则双Stone代数、半简单Nelson代数和预粗代数.通过建立这些粗代数中算子之间的联系,证明了:(a) 近似空间代数可转化为半简单Nelson代数和正则双Stone代数;(b) 粗Nelson代数可转化为预粗代数和正则双Stone代数;(c) 粗双Stone代数可化为预粗代数和半简单Nelson代数,从而将3个不同角度的研究统一了起来.     

The pseudo-linear semantics of interval-valued fuzzy logics

Triangle algebras are equationally defined structures that are equivalent with certain residuated lattices on a set of intervals, which are called interval-valued residuated lattices (IVRLs). Triangle algebras have been used to construct triangle logic (TL), a formal fuzzy logic that is sound and complete w.r.t. the class of IVRLs.In this paper, we prove that the so-called pseudo-prelinear triangle algebras are subdirect products of pseudo-linear triangle algebras. This can be compared with MTL-algebras (prelinear residuated lattices) being subdirect products of linear residuated lattices.As a consequence, we are able to prove the pseudo-chain completeness of pseudo-linear triangle logic (PTL), an axiomatic extension of TL introduced in this paper. This kind of completeness is the analogue of the chain completeness of monoidal T-norm based logic (MTL).This result also provides a better insight in the structure of triangle algebras; it enables us, amongst others, to prove properties of pseudo-prelinear triangle algebras more easily. It is known that there is a one-to-one correspondence between triangle algebras and couples (L,α), in which L is a residuated lattice and α an element in that residuated lattice. We give a schematic overview of some properties of pseudo-prelinear triangle algebras (and a number of others that can be imposed on a triangle algebra), and the according necessary and sufficient conditions on L and α.     

粗糙集代数与蕴涵格

在粗糙集的代数刻画方面,一个重要方法是在偶序对〈R（X）,R（X）〉构成的集合中通过定义基本运算寻找刻画偶序对所成集合的代数结构。其中,最有影响的代数结构是正则双Stone代数和Nelson代数。本文从偶序对〈T（X）,R（X）〉构成的集合入手,通过定义蕴涵运算证明了偶序对〈R（X）,R（X）〉所成集合构成蕴涵格,讨论了粗蕴涵格与
正则双Stone代数的关系。本文的讨论可为粗糙逻辑和粗糙推理奠定基础。     

由可精确测量元控制的弱可换的伪效应代数

主要研究了由可精确测量元控制的弱可换的伪效应代数中可精确测量元。证明了可精确测量元控制的弱可换的伪效应代数中可精确测量元是弱可换的伪正交代数代数。讨论了弱可换的伪效应代数与BZ-偏序集之间的关系。讨论了弱可换的伪效应代数商代数中可精确测量元与正规Riesz理想之间的关系。     

A Generalization of Local Fuzzy Structures

The class of bounded residuated lattice ordered monoids Rl-monoids) contains as proper subclasses the class of pseudo BL-algebras (and consequently those of pseudo MV-algebras, BL-algebras and MV-algebras) and of Heyting algebras. In the paper we introduce and investigate local bounded Rl-monoids which generalize local algebras from the above mentioned classes of fuzzy structures. Moreover, we study and characterize perfect bounded Rl-monoids.     

Very true operators in effect algebras

We introduce the concept of very true operator on an effect algebra. Although an effect algebra is only partial, we define it in the way which is in accordance with traditional definitions in residuated lattices or basic algebras. This is possible if we require monotonicity as an additional condition. We prove that very true operators on effect algebras can be characterized by means of certain subsets which are conditionally complete.     

Generalizations of the Continuous Logic

An order logic is studied, i.e., a generalization of the continuous logic to the case in an arbitrary argument of order r is determined instead of the operations of determination of maximum (disjunction) and minimum (conjunction). The new operation is expressed as a superposition of disjunctions and conjunctions of the continuous logic. Different classes of logical determinants—numeric characteristics of matrices that can be expressed through the operations of the continuous logic—are studied. Order determinants that are the generalizations of order logic operations to arguments in matrix form are studied. Determinants with different types of constraints on matrix subsets defining the matrix characteristic are described. For logical determinants, the properties that partly resemble the properties of algebraic determinants and computation formulas based on the operations of continuous logic are described. A predicate decision algebra generalizing the continuous logic to modeling of discontinuous functions is elaborated. A hybrid logic algebra is generalized to hybrid (continuous and discrete) variables. A logical arithmetic algebra, which includes continuous logical operations along with the four arithmetical operations, is described. A complex logic algebra in which the carrier set C is a field of complex numbers is developed. For all these logical algebras, main laws are formulated and their similarity to and distinction from the laws of the continuous logic are described. Generalizations of continuous logic operations as operations over matrices and random and interval variables are investigated. Their fields of application are described.     

Filters of residuated lattices and triangle algebras

An important concept in the theory of residuated lattices and other algebraic structures used for formal fuzzy logic, is that of a filter. Filters can be used, amongst others, to define congruence relations. Specific kinds of filters include Boolean filters and prime filters.In this paper, we define several different filters of residuated lattices and triangle algebras and examine their mutual dependencies and connections. Triangle algebras characterize interval-valued residuated lattices.     

On BCK algebras: Part II: New algebras. The ordinal sum (product) of two bounded BCK algebras

Since all the algebras connected to logic have, more or less explicitly, an associated order relation, it follows, by duality principle, that they have two presentations, dual to each other. We classify these dual presentations in “left” and “right” ones and we consider that, when dealing with several algebras in the same research, it is useful to present them unitarily, either as “left” algebras or as “right” algebras. In some circumstances, this choice is essential, for instance if we want to build the ordinal sum (product) between a BL algebra and an MV algebra. We have chosen the “left” presentation and several algebras of logic have been redefined as particular cases of BCK algebras. We introduce several new properties of algebras of logic, besides those usually existing in the literature, which generate a more refined classification, depending on the properties satisfied. In this work (Parts I–V) we make an exhaustive study of these algebras—with two bounds and with one bound—and we present classes of finite examples, in bounded case. In Part II, we continue to present new properties, and consequently new algebras; among them, bounded α γ algebra is a common generalization of MTL algebra and divisible bounded residuated lattice (bounded commutative Rl-monoid). We introduce and study the ordinal sum (product) of two bounded BCK algebras. Dedicated to Grigore C. Moisil (1906–1973).     

Completion of Boolean algebras in MSet

Two important algebraic structures in many branches of mathematics as well as in computer science are M-sets (sets with an action of a monoid M on them) and Boolean algebras. Of particular significance are complete Boolean algebras. And in the absence of the desired completeness one often considers extensions which remedy this lack, preferably in a “universal” way as a normal completion. Combining these two structures one gets M-Boolean algebras (Boolean algebras with an action of M on them, which are a special case of Boolean algebras with operators).The aim of this paper is to study the general notion of an internally complete poset in a topos, in the sense of Johnstone, and use it to give a minimal normal completion for an M-Boolean algebra.     

Relative negations in non-commutative fuzzy structures

In this paper we investigate the properties of the relative negations in non-commutative residuated lattices and their applications. We define the notion of a relative involutive FL-algebra and we generalize to relative negations some results proved for involutive pseudo-BCK algebras. The relative locally finite IFL-algebra is defined and it is proved that an interval algebra of a relative locally finite divisible IFL-algebra is relative involutive. Starting from the observation that in the definition of states, the standard MV-algebra structure of [0, 1] intervenes, there were introduced the states on bounded pseudo-BCK algebras, pseudo-hoops and residuated lattices with values in the same kind of structures and they were studied under the name of generalized states. For the case of commutative residuated lattices the generalized states were studied in the sense of relative negation. We define and study the relative generalized states on non-commutative residuated lattices. One of the main results consists of proving that every order-preserving generalized Bosbach state is a relative generalized Rie?an state. Some conditions are given for a relative generalized Rie?an state to be a generalized Bosbach state. Finally, we develop a concept of states on IFL-algebras.     

Isomorphism theorems on generalized effect algebras based on atoms

A well-known fact is that every generalized effect algebra can be uniquely extended to an effect algebra in which it becomes a sub-generalized effect algebra and simultaneously a proper order ideal, the set-theoretic complement of which is its dual poset. We show that two non-isomorphic generalized effect algebras (even finite ones) may have isomorphic effect algebraic extensions. For Archimedean atomic lattice effect algebras we prove “Isomorphism theorem based on atoms”. As an application we obtain necessary and sufficient conditions for isomorphism of two prelattice Archimedean atomic generalized effect algebras with common (or isomorphic) effect algebraic extensions.