Sharif Digital Repository

Three distinct areas in linguistic studies are typically considered, namely, syntax, semantics and pragmatics. Each category has a specific realm and deals with special linguistic phenomena. Presenting exact definition and clarification of the corresponding boundaries of each area is considered in both linguistics and philosophy of language. In order to explain the “meaning” for sentences of a language, this issue turns out to be vital. Representing the definition and evaluating the domain of each area, is the objective of the first chapter. In chapter two, some important semantic theories have been investigated. Since at first one semantic theory ought to clear its position about reference,... 

Network Motifs are subgraphs that appear more frequently in real networks than randomize networks. Frequent replication of a subgraph could imply evolution, network performance or some other particular reasons. From algorithmic perspective, network motif discovery in a graph is a difficult problem. Since, at least it includes the whole graph isomorphism. Hence, for solving this problem in practice, we need computable graphs. The existing algorithms so far, have high running times and memory usages. In this thesis, we present a new algorithm called CGQ. Within this algorithm, we use both QuateXelero and G-Trie algorithms which respectively have better performance in census of real networks... 

Security protocols assure the security of the communications in computer systems using techniques such as cryptographic primitives. However, the usage of such protocols is faced by the lack of fault tolerance, where a minor disruption could cause a destructive damage. Therefore, there is a requirement to assess the reliability of these protocols. In this thesis model checking of timed security protocols is done. Model checking process includes steps that will be modeling protocol with high level and human readable specification language named THLPSL and converting this specification to special kind of timed automata named XTA and model checking will be done with UPPAAL verification tool. We... 

Monitoring of activities of elderly and intelligent decisions about their living environment is a key challenge in smart environments. In the case of such challenges, correctness of system performance is highly dependent on how the model is designed. In the ambient intelligence (AMI) modeling, formal modeling is one of the best approaches because it supports certainty. In addition, time, location and mobility in AMI are crucial requirements, particularly in emergency treatment services. Ambient calculus is a formalism for describing mobility, process migration and message transfer, but it cannot express metric time duration. In this paper we propose an extension of ambient calculus with time... 

The amount of ever-growing generated data increases the need for automatic methods in text processing. As a solution, sentence compression and text summarization are considered as methods of managing and dealing with this huge amount of data. Additionally, Sentence compression is also useful in different text processing systems such as text summarization, news condensation, information extraction and question-answering systems. A sentence compression system takes a long sentence as input and returns a shorter form of the sentence in a way that its important information and grammaticality is preserved. In this thesis, we devise a rule-based extractive sentence compression method. This... 

In component-based design, each system consists of a set of heterogeneous components that are in interaction with each other. In this approach of design, computation is executed by the components, and their interactions are considered individually. BIP and Reo are coordination languages implemented in component-based modeling of systems. The BIP framework has a layered structure to separate interactions from the calculations. There are several approachesfor the formal definition of BIP layers. There are also semantics for BIP, based on two data-based and data-agnostic approaches. On the other hand, automata of records of a model is an operational semantics for Reo coordination language, one... 

Paraphrases are sentences or phrases, which convey the same meaning using different words. There are different definitions for paraphrasing and most linguists believe that, paraphrases approximately equivalent in meaning. Paraphrase recognition is useful in different natural language processing areas such as question answering, information extraction, plagiarism recognition and machine translation. In this thesis, the purpose is to present a method for paraphrase recognition, using deep semantic analysis and meaning representation of sentences. To achieve this purpose first, meaning features were defined for every syntactic category and semantic analysis of sentences alongside mapping of... 

With long-term evolution of large scale software systems, the study and engineering of architectural evolution becomes more and more important. In order to manage high level changes, the architects should plan the architecture evolution in a series of releases. Planning and analysis of architectural evolution is a challenge and plays a significant role in evolution management. An assessment solution could promote overall accuracy and quality of the evolution process. Compliance checking with expert-defined rules is a well-known assessment solution and could be applied in the field of architectural evolution. In this thesis, a solution is proposed in order to compliance check these evolution... 

Developing distributed systems is always harder than centralized systems, because in distributed systems there are problems like how nodes must collaborate with each other, throughput, latency and so on, that is not concerned in centralized systems. For solving this problem, It's better to have an abstract view of system to show this concerns. one of the coordination languages to have that abstract view of system, is Reo language. Reo language is a coordination language that describe how components of systems, can coordinate with each other. This project is built to decrease the distance between designing and implementing. In this project an abstract view of system which is in Reo language,... 

If we consider a point set on the plane as the vertices and straight-line segments between them as the edges of a graph, and weight of each edge is equal to its Euclidean length, from this kind of graphs, triangulation is the graph with maximum number of the edges. In a triangulation, dilation of any two vertices is equal to the ratio of their shortest path length to their Euclidean distance, and dilation of the triangulation is defined as the maximum dilation of any pair of its vertices. Dilation is a characteristic that shows how much a triangulation approximates a complete graph. In the minimum dilation triangulation problem, the objective is to find a triangulation of a given set of... 

By intertwining community daily life to electricity, high reliability and quality, safe, and low-cost services become among common expectations of electric energy customers. The substantial sources of fault events, however, lead to unexpected service interruptions. The exhaustion of existing devices, radial structure of current distribution networks, and lack of sufficient control and monitoring systems even worsen the situation. Therefore, investing in distribution systems in order to improve the service reliability and quality has been deemed as a proper strategy for electricity planners and operators. Various approaches have been proposed to achieve this aim. Among them, implementing...