Switched Ethernet is an Ethernet LAN that uses switches to connect individual nodes. This is popular because of its effective and convenient way of extending the bandwidth of existing Ethernets. Switched Ethernet is being considered by the industry community because of its open standardization, cost effectiveness, and the support for higher data rates up to 10Gbps. Even though many special-purposed solutions were proposed to support time constrained communication over Switched Ethernet, still there were some doubts about the real time handling capability of Switched Ethernet. To achieve reliable transmission guarantees for real time traffic over Switched Ethernet, it is important to measure the performance of Switched Ethernet networks for real time communication. In this thesis work we have observed the average end-to-end packet delay for real time traffic over a Switched Ethernet by simulation, which is very much essential for real time communication in industrial applications, where the communication is time-deterministic. In our thesis we used FCFS priority queuing in both the source nodes and switch. In this thesis we also discussed about the feasibility analysis for fixed sized frames and some traffic handling methods. We used 100mbp/s single full duplex Ethernet switch for our simulation. Finally simulation analysis and simulation results are discussed. Our purpose of simulation of Switched Ethernet networks is of good importance for the real time industrial applications.

For persons with disabilities, their impairments lead to many inconveniences in their daily life. Luckily, assistive technology devices can help compensate functional limitations and enable them to participate in the activities of daily life. In 2010, there were 126,693 disabilities in the Kaohsiung area. Subsidies provided by Kaohsiung city government and Kaohsiung county government reach respectively NT$39,145,000 and NT$ 25,489,000 in 2010. Nevertheless, such great amount of money invested does not work as it has been expected. There appear to remain a number of barriers. One such example would be that persons with disabilities lack the knowledge about assistive technology, so they do not know where to ask for help in the first place. On the other hand, lack of consideration for the needs of a person with disability result in them getting inappropriate assistive technology devices. These problems deserve the attention of government and related associations. This research aims to solve the problems between the supply and demand of assistive technology devices or services. It reviews and studies papers concerning the same issue in an attempt to create a new service platform. This platform is created according to information and suggestion gathered from experts of this field and voice from users of assistive devices. Their voices and assessments provide valuable direction to shape this new platform. This research assesses the possibility of this new assistive technology service platform from several aspects, including its political, legislative, supplying, and demanding dimensions. The purpose of this study is to reorganize diverse resources to provide a more convenient information-gathering method and to offer a complete service for disabilities people.

Renewable energy sources are getting much more important to reduce the increasing threat coming from greenhouse gases. Hydropower is the most important source of renewable energy. However, development of a hydropower project is a challenging engineering process. Several computer programs have been developed to make initial estimations on hydropower schemes. A computer program named RETScreen Small Hydro Project Model has been developed with the objective to make complete pre-feasibility studies including costing and financial analysis. Two case studies, which have been under construction in Turkey, will be used to check the accuracy of software in Turkish practice. Then in light of the results, RETScreen software will be used to make a pre-feasibility report on an existing multipurpose dam in Turkey. Electricity can be generated at existing dams which requires minor civil works. Porsuk Dam which is a 36 year old dam used for domestic, industrial and irrigation water supply will be evaluated for energy generation by constructing a penstock, powerhouse and installing electromechanical equipment.

Pathfinding algorithms used in today&rsquo / s computer games consider path length or a similar criterion as the only measure of optimality. However, these games usually involve opposing parties, whose agents can inflict damage on those of the others&rsquo / . Therefore, the shortest path in such games may not always be the safest one. Consequently, a new suboptimal offline path search algorithm that takes the threat sources into consideration was developed, based on the A* algorithm. Given an upper bound value as the tolerable amount of damage for an agent, this algorithm searches for the shortest path from a starting location to a destination that would cause the agent suffer no more damage than the specified maximum. Due to its mentioned behavior, the algorithm is called Limited-Damage A* (LDA*). Performance of LDA* was tested in randomly-generated and hand-crafted fully-observable maze-like square environments with 8-way grid-abstractions against Multiobjective A* (MOA*), which is a complete and optimal algorithm. It was found to perform much faster than MOA* with allowable sub-optimality in path length.

Siltation in reservoirs is becoming an important problem as the dams are getting older in the world. The general dam practice has been implemented in a sequence that / planning, design, construction, operation of dam until the accumulated sediment prevents its purpose function or functions. Unfortunately, effects of sedimentation and fate of the left over dams in the future are not figured. Indeed, these negative effects could be avoided, life of the reservoir can be prolonged and even the reservoir will last forever by minimizing the sedimentation. Therefore in this study, the methods that provide extension of reservoir life are discussed hydraulically, economically and applicability point of view. In addition, there is open source package program RESCON which examines and compares some sediment removal techniques economically and also hydraulically. RESCON is used in conjunction with several cases / namely &Ccedil / ubuk Dam-I, Bor&ccedil / ka Dam and Muratli Dam. Moreover, some sensitivity analyses are carried out in order to scrutiny of the program for Turkish economic conditions.

The overall objective of this thesis is to assess the financial, technical and social feasibility of investing in modern Automated People Movers (APM) transportation systems, generally known as monorails, in METU campus which presents a unique opportunity to fulfill the modern-day transportation needs of METU campus. This study complements the Presidency Office&rsquo / s long term goal to integrate environmental, social and economic sustainability into the policies, practices and culture of the university and ultimately reduce the consumption of all resources on campus and traffic congestion and accidents. In this context, the consequent cost-benefit effects of the proposed monorail system on campus life were quantified in monetary expressions and the corresponding multi-criteria feasibility assessment including: Break-even Analysis, Cost Effectiveness Assessments and Cost Benefit Analysis have been done successfully. According to these analyses the overall capital cost of system is $46.5 million which covers the 24 months project construction period, and an additional annual operating and maintenance cost of $2 million will span the 30 year project life time. Three different scenarios were proposed for financing the project and relevant break-even points were determined for each of the scenarios. Eventually, it appears that based on the evaluations, constructing such a transit system in METU campus will be cost effective and will certainly enhance the transportation, and will contribute to the institutional improvements and environmental preservation schemes of METU campus.

The objective of this thesis is to develop a decision support tool to assess the feasibility of a hydro electrical power plant (HEPP) investment option by estimating its profitability under various scenarios. The decision support tool may help the decision makers to understand critical parameters that affect the internal rate of return (IRR) of a HEPP investment, create realistic scenarios by assigning different values to these parameters and monitor profitability under various scenarios. The information and the assumptions to construct the proposed decision support tool have been collected by conducting interviews with experts and its reliability has been tested by a real case study.

There has been lots of research done on customer retention in electronic commerce by using different theories and Model. But there is very less or no work done based on MODE (Motivation and Opportunity as Determinants) model by Fazio 1990. This thesis used MODEL to predict the factors that determine customer in retention in EC. Motivation and opportunity are the most important determinants for consumers choosing an online store. To study motivation and opportunity mechanisms underlying consumer-e-retailer exchange relationship, this research takes a new perspective, a perspective directed toward customer intention to repurchase or customer retention. By integrating MODE model of Fazio 1990 with ¡V process feasibility, switching cost, and relational bond. This study develops an integrated model of consumer retention in an e-retailer. Data for the study was collected using an online survey distributed via email, posting link on the social networking sites linkedin, facebook, and discussion boards¡¦ bbs, NSYSU website. Hypotheses were tested using structural equation modeling of SmartPls. Findings of the study imply that consumer retention in an online store is the affect of consumer motivation towards same online store. Specifically, a consumer¡¦s attitudes toward the key components of his/her entire online purchase experience (i.e., financial bond, social bond, structural bond, time and money saving, and switching cost) constitute the key drivers of consumer retention. Findings also indicate that motivation is intrinsically beneficial. If a consumer motivated by an online store, consumer will come back in the future to repurchase from the same e-retailer. Further, findings suggest that though motivation has a direct effect on future intentions and repurchase. Additionally, findings of the study imply that the effects of motivation on repurchase intention, but the opportunities available from another online store doesn¡¦t affect consumer attitude towards repurchase intention. Moreover search and experience type product moderately affect consumer attitude towards repurchase intention.

Enabling multi-hop wireless mesh networks with multi-input multi-output (MIMO) functionality boosts network throughput by transmitting over multiple orthogonal spatial channels (spatial multiplexing) and by performing interference cancellation, to allow links within interference range to be concurrently active. Furthermore, if the channel is in a deep fade, then multiple antenna elements at the transmitter and/or receiver can be used to transmit a single stream, thereby improving signal quality (diversity gain). However, there is a fundamental trade-off between boosting individual link performance and reducing interference, which must be modeled in the process of optimizing network throughput. This is called the diversity-multiplexing-interference suppression trade-off. Optimizing network throughput therefore, requires optimizing the trade-off between the amounts of diversity employed on each link, the number of streams multiplexed on each link and the number of interfering links allowed to be simultaneously active in the network. We present a set of efficient heuristics for one-shot link scheduling and stream allocation that approximately solve the problem of optimizing network throughput in a single time slot. We identify the fundamental problem of verifying the feasibility of a given stream allocation. The problems of general link scheduling and stream allocation are very closely related to the problem of verifying feasibility. We present a set of efficient heuristic feasibility tests which can be easily incorporated into practical scheduling schemes. We show for some special MIMO network scenarios that feasibility is of polynomial complexity. However, we conjecture that in general, this problem, which is a variation of Boolean Satisablility, is NP-Complete.

<p>Ill-posed sets of linear equations typically arise when discretizing certain types of integral transforms. A well known example is image reconstruction, which can be modelled using the Radon transform. After expanding the solution into a finite series of basis functions a large, sparse and ill-conditioned linear system arises. We consider the solution of such systems. In particular we study a new class of iteration methods named DROP (for Diagonal Relaxed Orthogonal Projections) constructed for solving both linear equations and linear inequalities. This class can also be viewed, when applied to linear equations, as a generalized Landweber iteration. The method is compared with other iteration methods using test data from a medical application and from electron microscopy. Our theoretical analysis include convergence proofs of the fully-simultaneous DROP algorithm for linear equations without consistency assumptions, and of block-iterative algorithms both for linear equations and linear inequalities, for the consistent case.</p><p>When applying an iterative solver to an ill-posed set of linear equations the error typically initially decreases but after some iterations (depending on the amount of noise in the data, and the degree of ill-posedness) it starts to increase. This phenomena is called semi-convergence. It is therefore vital to find good stopping rules for the iteration.</p><p>We describe a class of stopping rules for Landweber type iterations for solving linear inverse problems. The class includes, e.g., the well known discrepancy principle, and also the monotone error rule. We also unify the error analysis of these two methods. The stopping rules depend critically on a certain parameter whose value needs to be specified. A training procedure is therefore introduced for securing robustness. The advantages of using trained rules are demonstrated on examples taken from image reconstruction from projections.</p> / <p>Vi betraktar lösning av sådana linjära ekvationssystem som uppkommer vid diskretisering av inversa problem. Dessa problem karakteriseras av att den sökta informationen inte direkt kan mätas. Ett välkänt exempel utgör datortomografi. Där mäts hur mycket strålning som passerar genom ett föremål som belyses av en strålningskälla vilken intar olika vinklar i förhållande till objektet. Syftet är förstås att generera bilder av föremålets inre (i medicinska tillämpngar av det inre av kroppen). Vi studerar en klass av iterativa lösningsmetoder för lösning av ekvationssystemen. Metoderna tillämpas på testdata från bildrekonstruktion och jämförs med andra föreslagna iterationsmetoder. Vi gör även en konvergensanalys för olika val av metod-parametrar.</p><p>När man använder en iterativ metod startar man med en begynnelse approximation som sedan gradvis förbättras. Emellertid är inversa problem känsliga även för relativt små fel i uppmätta data. Detta visar sig i att iterationerna först förbättras för att senare försämras. Detta fenomen, s.k. ’semi-convergence’ är väl känt och förklarat. Emellertid innebär detta att det är viktigt att konstruera goda stoppregler. Om man avbryter iterationen för tidigt fås dålig upplösning och om den avbryts för sent fås en oskarp och brusig bild.</p><p>I avhandligen studeras en klass av stoppregler. Dessa analyseras teoretiskt och testas på mätdata. Speciellt föreslås en inlärningsförfarande där stoppregeln presenteras med data där det korrekra värdet på stopp-indexet är känt. Dessa data används för att bestämma en viktig parameter i regeln. Sedan används regeln för nya okända data. En sådan tränad stoppregel visar sig fungera väl på testdata från bildrekonstruktionsområdet.</p>