Sharif Digital Repository

In this thesis we study one of the applications of algebraic topology to computer science and define some tools to analyze concurrent programs. For this purpose a geometric space is corresponded to every concurrent program and a partial order is considered on this space, so every path on it corresponds to an execution of the program. Some of these paths which are dihomotop (homotop in partial ordered spaces) with each other induce the same execution of the program. By defining “Fundamental Category” in which objects are points of the space and morphisms are dihomotopy classes, the space that should be analyzed shrinks to a smaller one. By defining component category in the next step, without... 

Due to the data centers rapid growth and introduction of a new basic type of massive data processing platforms which requires accelerators to speedup computation and enhance the efficiency and reduce power consumption, using accelerators is inevitable. Communication and data transfer time between software and hardware is the most of time spent on the use of accelerators. By optimizing this part of the hardware / software platform, we have achieved substantial results in this area. The aim of our study is to organize a survey of real accelerator characteristics. To figure out its defects and main drawbacks, in addition to improving the overall efficiency of system. The implementation of... 

Internet of Things is a promising paradigm consensus of different technologies. It has gained increasing popularity during recent years. However it is still in its infancy phase. Heterogeneous and constrained devices, resource discovery, identification, scalability, mobility, difficulty of application development and deployment, and security requirements are some of the most important concerns that must be resolved in order to achieve more maturity. To address these challenges, several IoT platforms have been proposed. In some recent of them, a concept called virtual object(vo) has been introduced. A virtual object is a virtual representation of a physical device. Using this concept, many...