Sharif Digital Repository

Modeling languages are needed to describe the conceptual construct underlying software. Several modeling languages have been proposed during the last decades. Cognitive complexity is one of the common problems in designing modeling languages. Users have to split their attention and cognitive resources between two different tasks when working with complex language: solving the problem and understanding the elements composing the language. Several researches have been accomplished to evaluate cognitive complexity of modeling languages, among them, metric based and empirical approaches aremore important and convenient than others. In this paper, we compared these two methods. Results show that... 

Peer-to-peer (P2P) networks are beginning to form the infrastructure of future applications. Heavy network traffic limits the scalability of P2P networks. Indexing is a method to reduce this traffic. But indexes tend to become large with the growth of the network. Also, limiting the size of these indexes causes loss of indexing information. In this paper we introduce a novel ontology based index (OI) which limits the size of the indexes without sacrificing indexing information. We show that the method can be employed by many P2P networks. The OI sits on top of routing and maintenance modules of a P2P network and enhances it. The OI prunes branches of search trees which have no chance to... 

Peer-to-peer (P2P) networks are beginning to form the infrastructure of future applications. Computers are organized in P2P overlay networks to facilitate search queries with reasonable cost. So, scalability is a major aim in design of P2P networks. In this paper, to obtain a high factor of scalability, we partition network search space using a consistent static shared upper ontology. We name our approach semantic partition tree (SPT). All resources and queries are annotated using the upper ontology and queries are semantically routed in the overlay network. Also, each node indexes addresses of other nodes that possess contents expressible by the concept it maintains. So, our approach can be...