This paper characterizes the development of modular branching structures that satisfy three assumptions: (a) subapical branching, meaning that new branches can be created only near the apices of the existing branches, (b) nite number of module types and states, and (c) absence of interactions between coexisting components of the growing structure. These assumptions are captured in the notion of...

We introduce new proof systems for propositional logic, simple deduction Frege systems, general deduction Frege systems and nested deduction Frege systems, which augment Frege systems with variants of the deduction rule. We give upper bounds on the lengths of proofs in these systems compared to lengths in Frege proof systems. As an application we give a near-linear simulation of the proposition...

Employing the notions of the strong $L$-topology introduced by Zhangand the $L$-frame introduced by Yao  and the concept of $L$-enrichedtopological system defined in the present paper, we constructadjunctions among the categories {bf St$L$-Top} of strong$L$-topological spaces, {bf S$L$-Loc} of strict $L$-locales and{bf $L$-EnTopSys} of $L$-enriched topological systems. All of theseconcepts are ...

In this work we present a microbenchmark methodology for assessing the overheads associated with nested parallelism in OpenMP. Our techniques are based on extensions to the well known EPCC microbenchmark suite that allow measuring the overheads of OpenMP constructs when they are effected in inner levels of parallelism. The methodology is simple but powerful enough and has enabled us to gain int...

The nested transaction model was introduced to satisfy the requirements of advanced database applications. Moreover, it is currently the basic transaction model for new database applications like work¯ow systems and new database systems like mobile databases and object-relational databases. Though there are several performance evaluation studies of different concurrency control mechanisms in ne...

Active database management systems(ADBMS) uses Event-Condition-Action rules (ECA rules). Each ECA rule speciies what action to be taken when an event occurs and the speciied condition is satissed. In this paper, we introduce a concurrency control scheme for handling nested cooperative transactions using detached mode ECA rules of an ADBMS. A state transition model has been proposed to specify d...

Persistent and distributed object systems have to cope with chaos resulting of concurrent accesses and failures. This suggests the properties of atomicity, isolation and persistence of eeects. This paper presents the Eos action model which is an interpretation of Moss's model. We focus on Eos's eecient support for nested isolation which upholds an adaptive granule of locking based on complex ob...