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A wireless mesh network (WMN) is a multihop wireless network consisting of a large number of wireless nodes of which some are called gateway nodes and connected with a wired network. Wireless mesh network have attracted much research attention recently due to its flexibility, low-cost and robustness, which facilitate its usability in many potential applications, including last-mile broadband Internet access, neighborhood gaming, Video-on-Demand (VoD), distributed file backup, video surveillance, etc. The broadcast nature, the lack of infrastructure as well as the flexible deployment nature of wireless mesh networks make it different from wired networks, therefore more attention in designing the wireless mesh network is needed to maintain a good performance of this promising technology. We, in this study, investigate the wireless mesh network design taking into consideration three design factors seeking an improvement in the network performance by reducing the interference influence in the network, improving the network reliability to satisfy more requests, and securing the network against malicious eavesdropping attacks. Our design is presented into three sub-problems; sub-problem (1), which seeks an interference-aware robust topology control scheme, sub-problem (2) which seeks a multipath routing scheme, and sub-problem (3) which seeks a secure key management scheme. Through simulations and comparisons with previous work, we show that our proposed solutions outperform previous schemes in providing a better network performance in terms of reducing the network interference, satisfying more number of requests and increasing the network resistance to malicious eavesdropping attacks.

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The space sector has been evolving due to the fast-technological advancements generating a reduction of manufacturing, cost and size in space missions, where highly capable performing small satellites are becoming the standard in this industry. Furthermore, the high launching cost limits the trend of cost reduction for the space missions, since the small satellites are sent as a second payload. An alternative to reduce this limitation is using reusable launchers which are key in the future of space industry, once they are optimized in efficiency and reliability. Therefore, an opportunity of design is presented, since the increase of small satellites missions requires a reduction of the cost in launch services a suitable option for the future market are the reusable launchers. The problematic of using recovery systems and reuse parts of the vehicle is the increase of weight due to the added systems that the vehicle needs to be recovered. This paper presents different engines and calculate the performance of each engine based on the needs of missions for small satellites. The starting conditions will be that the payload needs to be launched in low circular or elliptical orbits (altitudes of between 300 and 650 km) and the engine has the ability of vertical take-off, vertical landing. The design will also take into account the possibility of reusing parts of the vehicle and the reentry capability. Different combination of engines and fuels are setup in various configurations. For each case the mass analysis will be developed which will allow to calculate the performance for each engine. The important parameters are the number and type of engines, the ratios of the masses, the thrust-to-weight ratio and specific impulse. Once the mass analysis is obtained the following procedure is the selection of the design considering the empty mass. The best combination of characteristics of the engines will be the suitable candidate. Different assistance systems and techniques for the recovery are assessed to obtain a suitable option to improve the efficiency. The expected results are the calculation of the engine performance and how the selected design can be suitable for the space launcher sector for the small satellites. The expected results are a feasible vehicle for small satellites design based in the calculation of the engine parameters together with an efficient launch recovery system. The conclusion is that the space sector can benefit from the design, demonstrating that a launch vehicle with the reusable characteristics.

Many software organizations are actively pursuing software process maturity. One of the cornerstones of software process improvement is the definition of processes in key process areas [Paulk 93a]. As development organizations define processes to increase their project's maturity, a method is needed to make the defined processes reusable by the organization and to tailor these reusable processes for reuse on other projects. The thesis is that the development and implementation of a method to construct reusable corporate process definitions and to tailor them to specific projects will significantly increase the corporate level of process reuse. Therefore, this thesis investigates how to pragmatically and systematically standardize and replicate project-specific processes in an industrial software setting. Process reusability and attributes of process reusability are discussed and a systematic and standardized method for process reuse is presented. The utility of the methodology is demonstrated by its application to software process definition activities at PRe Inc., where the level of process reuse both before and after its application has been measured. Process reuse increased from 41 % in 1994 to 55% in 1995. PRC also saw a 10 to 1 improvement in time to define a project-specific process. / Master of Science

Software reuse via component libraries suffers from the twin problems of code location and comprehension. The Intelligent Code Object Planner (ICOP) is a cognitively motivated system that facilitates code reuse by answering queries about how to produce an effect with the library. It can plan for effects which are not primitive with respect to the library by building a plan that incorporates multiple components. The primary subsystems of ICOP are a knowledge base which describes the ontology of the library, a natural language interface which translates user queries into a formal effect language (predicates), a planner which accepts the effect and produces a plan utilizing the library components, and an explanation generator which accepts the plan and produces example code illustrating the plan. ICOP is currently implemented in Prolog and supports a subset of the Windows 3.0 APL

In this work an electronic warfare system is restructured to service oriented architecture. Service Oriented Architecture (SOA) is a paradigm that realizes rapid and low cost system development. The most important characteristics of SOA are standard based interoperability, which allows services developed on different platforms to run together, and dynamic composition via discovery, which provides dynamic composition of application at runtime using the existing services. The old warfare system that was developed by ASELSAN Inc. contained embedded software and was designed using traditional object oriented techniques. In this thesis, we have extracted services out of the system and restructured the warfare system based on service oriented principles. In this thesis, we have focused on the dramatic effect of reusability when SOA is introduced to the electronic warfare system. To understand the effect of service orientation, the new system is evaluated in terms of line of code, memory consumption and extra CORBA interface communication overhead.

<p>In an information system which includes plenty of information services, we are always seeking a solution to enhance efficiency and reusability. Emergency medical service system is a classic information system using application integration in which the requirement of information flow transmissions is extremely necessary. We should always ensure this system is running in best condition with highest efficiency and reusability since the efficiency in the system directly affects human life.</p><p>The aim of this thesis is to analysis emergency medical system in both qualitative and quantitative ways. Another aim of this thesis is to suggest a method to judge the information flow through the analysis for the system efficiency and the correlations between information flow traffic and system applications.</p><p>The result is that system is a main platform integrated five information services. Each of them provides different unattached functions while they are all based on unified information resources. The system efficiency can be judged by a method called Performance Evaluation, the correlation can be judged by multi-factorial analysis of variance method.</p>

<p>A substantial amount of time and efforts in the initial stages of creating a software system is spent capturing requirements, deciding what software to use and creating technical prototypes to gain confidence in the decisions that have been made are correct. This thesis targets the domain of Mobile Learning with the aim of optimizing these initial stages of a new project by identifying commonalities and architectural patterns found in six existing software systems related to research projects in the domain.</p><p>The results present a set of requirements, guidelines and/or an initial conceptual architecture that can be extended or adapted to a broad range of software systems.</p>