Sharif Digital Repository

In recent years, most of the research in the field of reliability has been carried out over finding optimal combinations of units and their structures, trying to maximize the reliability of the system with respect to its cost. Numerous methods have been introduced. But, in this research, we introduce a new approach based on game theory, considering the system’s reliability and its cost as two players of a game. These two players start bargaining in search for an equilibrium point which none of them can violate seeking a better outcome. Finally, we show the superiority of our method by solving a traditional problem and comparing our results with the results of other optimization methods  

In this project, a convolutional neural network is trained to classify Persian handwritten digits and different neural network models are compared for this problem. To train and evaluate this network, the "HODA" data set has been used, which includes 80,000 images of Persian handwritten digits, including 60,000 images of training data and 20,000 images of test data. In the modeling section, we have used a comparison of recent top architectures of convolutional neural networks to identify Persian and English handwritten numbers. In this experiment, the Tensorflow library in the Python programming language was used. Parameter values and network hyper parameters are obtained from the values... 

Gini coefficient is the most prevalent index for the measurement of inequality and is usually extracted by means of nominal variables based on income or expenditures of households. In this study we have extracted more accurate Gini coefficients. By using the raw data of Households Budget Survey (HBS) and STATA software, a special CPI for each household of the sample is extracted. Subsequently nominal expenditures are deflated by these special CPIs, and at last, Gini coefficients are extracted from real expenditures. Our findings indicate that in recent years, extracted Gini coefficients are remarkably higher than prevailing ones.
 

To reduce construction costs selecting the optimal route for water conveyance line entails ample observation and considering all effective parameters. Some part of Aidoghmoush dam project of water conveyance line located in Azerbijan the east has been investigated in this research. First, by investigating, effective factors in determining the optimal route have been identified and then categorized into two groups of quantitative criteria(technical-economical) and qualitative criteria(environmental). Quantitative objectives include: slope, transportation system, infrastructures, fault and soil type. Qualitative objectives include: environmental considerations, land use and land cover. Because... 

Nanotechnology requires a number of infrastructures for reaching its sustainable development. For each step of its development , various infrastructures should be studied and prepared in advance.In this direction, by introducing and recognizing the priority of Iran Nanotechnology R&D indexes ,the present research is going to propose an effective help. In this case, after studying the related literature and gathering the needed data , 27 indexes were recognized. Then , the indexes were divided in 7 criteria.In order to find the priority of the applied indexes , Fuzzy Multiple Criteria Decision Making (FMCDM) was applied. As the weighting of 7 criteria had been found by FANP , the... 

As you know in lean supply chains, it is tried to: reduce the wastes of resources and achieve more production with lower consumption of resources. This system is very well suited for many supply chains in which the final determinant factors are price and quality. In contrast, recently, the concept of agile supply chain has been introduced, insisting on flexibility and high service level. Opposite to lean supply chain, agile supply chain needs safety stock to be able to respond to market’s changes.
Regarding the dissimilarities of these models –including the disagreement in the allocation of safety stock to nodes– In this thesis, in addition to studying and comparing these two approaches,... 

One of the security issues in database outsourcing scenario is the correctness of the query results. Correctness verification includes integrity, completeness and freshness of the results. Most of the proposed approaches for correctness verification impose high overhead on the components of the scenario which prevents the scenario to implemented in practical applications. In this thesis, we have proposed a probabilistic approach which imposes acceptable overhead for correctness verification of returned results of service provider. The approach uses the previous behavior of the service provider to calculate a trust value toward it which is used to adjust the imposed overhead. In other words,... 

The fascinating subject of heavy fermion physics in rare-earth and actinide systems has been a challenge for theoretical and experimental investigations for decades. Kondo Necklace model is one of the promising models in the study of strongly-correlated heavy fermion compounds, which is studied in this project.One of the methods to diagonalize a Hamiltonian properly, regardless of system size, is the continuous unitary transformation. In this approach, the Hamiltonian is considered as a function of a flow parameter. The Hamiltonian is transformed to a simpler form (diagonal or band-block diagonal) under a flow equation which is based on applying infinite numbers of infinitesimal unitary... 

Due to the negative effects of conventional plastics on the environment, especially in the packaging sector, extensive efforts have been put to replace these polymers with biodegradable polymers. Starch is one of the biodegradable polymers which has attracted a lot of attentions because of low cost and good process ability. Native starch has the form of granule and can be processed to a continuous phase after gelatinization in the presence of a plasticizer. The resulting material is a biodegradable plastic-like material called thermoplastic starch (TPS) which is processed using conventional technologies, but suffers from low mechanical properties and high hydrophilicity. Addition of... 

Lean Management is a set of modern procedures that uplifted Japanese manufacturers' status in global markets. The core principle of lean management is to eliminate every process or operation which creates no value, directly and indirectly. To this day, lean has been more focused on production. But eliminating the wastes in service organizations in crucial, due to nature of service. In this thesis, first the lean concept and the Middle East bank is discussed and a literature review on lean studies is presented. Then a vision for the future is envisioned and a questionnaire for conducting a Corporate Diagnosis is developed. In the next step, a lean management system for the bank is implemented... 

The development of embedded systems in safety critical applications leads to using fault tolerant methods to improve their dependability. Among the various fault tolerant methods, recently, software based methods are more appealing during to the following reasons: 1) They are applicable to the Commercial-Off-The Shelf (COTS) processors and lead to reduction in cost and time to market, 2) Unlike the traditional hardware based internal error detection methods, software based methods fault coverage are more promising, and 3)Software-based methods are cheaper, quicker and do not require any hardware modifications. The technology scaling trend in recent years, made system more vulnerable to... 

By investigating reports of severe and destructive earthquakes of the past years we have realized that shear-wall structures most of the times had better seismic performance and more reliability than moment resistance frames. Asymmetrical arrangement of shear walls due to architectural limitations caused distortions in the structure. On the other hand, seismic regulation don’t compliance existence of twisting moment in the structures. What was said are all the most important reasons for not employing asymmetric shear wall sets in the structures by designers. The purpose of this study is to compare the seismic behavior of symmetric moment frame structures with seismic behavior of symmetric... 

Nowadays, Gas turbines are developing more than before and one of the most important components of these turbines improving continuously is their combustor. In the recent years strict standards for controlling the amount of pollutants releasing from aero engines have been established and these standards are moving towards limiting these pollutants. Hence one of the most important criteria of combustor design is keeping its emissions at a lowest possible amount. In this study, at first an algorithm for combustor design has been calculated and then by means of this algorithm the combustor of CF6-80E1A4 engine is designed again. The amount of the produced emissions of the designed combustor has...