one of the problems of learners that often impairs learning a second language is syntactic errors. therefore, the present study investigates the syntactic errors of arab speakers learning persian. this research is based on contrastive analysis approach. in this article, interlingual syntactic errors committed in learner’s writings are studied, using field method and through a content analysis o...

logical form or covert syntax is a syntactic level introduced in recent generative approaches. using the ideas of first-order predicate logic, it interprets the strings whose elements cannot move in s–structure, because an element moves if it does not acquire its necessary scope. but unlike the predicate logic, logical form is based on syntactic principles and rules. therefore, logical form is ...

This paper is a survey of recent results in the theory of nite semigroups using syntactic techniques. This involves manipulating pseudoidentities and the study of relatively free proonite semigroups, whose structure encodes algebraic and combinatorial properties common to the members of a pseudovariety of semigroups. These techniques are illustrated with applications in the study of semigroups ...

Classical normalisation removes structural anomalies that may occur in relations. These anomalies are defined by analysing various forms of predicates involving the attributes of the relations and by considering the implications of sequentially performed updating processes. The extension suggested in this paper takes into account the implications of performing update processes not necessarily s...

We define new subclasses of the class of irreducible sofic shifts. These classes form an infinite hierarchy where the lowest class is the class of almost finite type shifts introduced by B. Marcus. We give effective characterizations of these classes with the syntactic semigroups of the shifts. We prove that these classes define invariants shift equivalence (and thus for conjugacy). Finally, we...

For a pseudovariety V of ordered semigroups, let S (V) be the class of sofic subshifts whose syntactic semigroup lies in V. It is proved that if V contains Sl− then S (V∗D) is closed for taking shift equivalent subshifts, and conversely, if S (V) is closed for taking conjugate subshifts then V contains LSl− and S (V) = S (V∗D). Almost finite type subshifts are characterized as the irreducible e...

This paper addresses the problem of forbidden states of non safe Petri Net (PN) modelling discrete events systems. To prevent the forbidden states, it is possible to use conditions or predicates associated with transitions. Generally, there are many forbidden states, thus many complex conditions are associated with the transitions. A new idea for computing predicates in non safe Petri nets will...

“Petri nets are monoids” is the title and the central idea of the paper [7]. It provides an algebraic approach to define both nets and their processes as terms. A crucial assumption for this concept is that arbitrary concurrent composition of processes is defined, which holds true for place/transition Petri nets where places can hold arbitrarily many tokens. This paper defines a similar concept...

In this paper, we present an approach to define the semantics for object-oriented modeling languages. One important property of this semantics is to support underspecified and incomplete models. To this end, semantics is given as predicates over elements of the semantic domain. This domain is called the system model which is a general declarative characterization of object systems. The system m...