Sharif Digital Repository

In this thesis we introduce a new methodology to solve the problem of multi-objective control design of linear output-feedback with a constraint on the order of controller. This problem can be formulated as a set of linear matrix inequalities and an additional rank constraint. This constraint is highly non-convex and makes this optimization problem NP-hard. The proposed methodology results in methods which are multi-step and in each step a convex optimization problem shall be solved. This methodology can consider any combination of different design objectives such as H2 performance, H1 performance, passivity and regional pole assignment. In the development of described methodology, a... 

In recent decades, desulfurization processes have become essential to decrease environmental pollution due to the emission of sulfur from fuels. In this study, in order to desulfurize liquid fuel, a model fuel (normal heptane) was investigated under visible light ) 350-watt sodium lamp(, using H2O2 as oxidant and methanol as a solvent in the presence of Cu-C-TiO2 nanostructure. C-TiO2 was synthesized by the hydrothermal method. In order to modify and improve the properties, we doped the copper metal by impregnation method with different loading of Cu. Experimental results exhibited the highest activity among samples attributed to 0.5% Cu-C-TiO2 Which caused 98.27% degradation of DBT after 2... 

The project schedule is used as a key tool for managers to measure the progress of the project and prevent the deviation of the project from achieving its goals.Project scheduling started with manual methods. After a while, due to the increase in the size of projects and their complexity, the efficiency of traditional methods decreased. After the advances in computer sciences, scientists and experts had moved towards intelligentization and automation.During the past three decades, despite the attention of both academic and industrial fields towards automatic planning and scheduling of projects, Most of the researches focused on construction projects, and unfortunately, a few attentions have... 

Detecting defects in financial statements is crucial because such defects can impact the transparency, accuracy, and reliability of financial reports and influence the decision-making of stakeholders. This study aims to provide a novel approach for identifying defects in the financial statements of companies listed on the Tehran Stock Exchange. In this research, a defect is defined as a difference in data items between audited and unaudited financial statements, which may indicate either unintentional or intentional deviations or signal a potential fraud. The data for this study was automatically collected from the Codal system and includes both audited and unaudited financial reports in the... 

Today, the digital transformation has increasingly confronted software development companies with numerous requests for the production of custom software. Over time, these companies have realized that paying attention only to the technical aspect is not enough for delivering a product that functions correctly; the social dimension must also be considered. Consequently, many agile software development methods have been developed. However, an important point to note is that implementing and maintaining these methods involves many intricacies, with the most significant being the management of interpersonal relationships. With the continuous expansion of technology and the advancement of... 

The aim of this research is to develop and implement a deep reinforcement learning algorithm for portfolio management in the Tehran stock market, which is considered an emerging market with distinct patterns compared to the stock markets of developed countries. In this study, in addition to the market price data extensively used in previous research, we leverage fundamental ratio data extracted from company financial reports, which have received less attention. Furthermore, the research scope is limited to stocks in the mining and metal industries to enable the utilization of specific industry features, such as susceptibility to global prices of a key commodity. The portfolio management... 

The breadth and intertwining of the concepts of the Scrum Agile framework has made it difficult to understand the details in relation to each other correctly and quickly, and has faced learning Scrum with a challenge; because the newbies have to choose between schematic and imprecise but general images showing connections and detailed and precise but unstructured texts. On the other hand, the different approaches of Scrum implementation in different organizations according to the different conditions of the organizations and the specific ideas of each organization to personalize Scrum in the places that Scrum has given them this permission, have made the Scrum teams willing to learn as much... 

In mass casualty incidents such as earthquakes, hospitals and emergency response systems face significant challenges. To manage this critical situation, transfer points have been introduced as a strategic solution, enhancing the speed and efficiency of casualty transfers, thereby improving the overall performance of hospital services. The aim of this study is to develop a discrete-event simulation model that simulates and evaluates the provision of services to casualties at transfer points while predicting the optimal number of resources needed, including ambulances, triage staff, and medical personnel, in various emergency conditions. Additionally, a location model is designed to optimally... 

Supply chain management aims to increase customer satisfaction and satisfy demand with the lowest cost by establishing coordination and cooperation among the chain members. However, considerable concerns along supply chain management are reported from both academicians and practitioners. Security, visibility, transparency and traceability are the main challenges confronting supply chain management. The emerging technology named Blockchain is able to address the mentioned challenges by integrating with supply chain management. A prominent point to consider is that whether it is absolutely necessary to adopt blockchain technology in a system or not. If yes, how blockchain should be implemented... 

Greenhouse gases have a large share in pollution and global warming, and carbon dioxide is the main component of more than 80% of greenhouse gas emissions. For this reason, governments are looking for policies at the national and international level to reduce carbon emissions. In this research, using the system dynamics approach, a comprehensive model of the relationship between society, economy and carbon emissions in Iran has been designed. System dynamics is a method to study complex systems, which is used in this research because of the interactions between different parts of society, economy and carbon emissions and to better understand the relationship between them. First, the model is... 

Studies have shown that by reducing the stiffness of structures the seismic load imposed on them is reduced. In this research the effect of two different precast connections on the seismic response of precast concrete structures with shear walls during earthquakes was studied. The connections were vertical connections and were used to connect the two halves of the shear walls together. The results were compared with that of a wet connection. In this research 46 different structures were analyzed. The buildings were 9, 6 and 3 stories. In order to obtain the best seismic behavior different combinations of steel were considered among the connections. The seismic behavior of the structures were... 

Today, knowledge is the most important resource in software development. The success of software development relies on the exchange of knowledge between software developers working in different agile teams. The purpose of this research is to determine the size of agile teams according to knowledge sharing factors. Knowledge sharing factors between work teams have been extracted by searching articles; Then, all these factors, which are classified into five main categories: individual, organizational, technological, cultural, and geographical, were investigated and separated according to the working conditions in Iran, and finally, the important factors were identified by the evaluation of... 

Due to the intensification of competition in real markets and the increase in customer needs, manufacturers are forced to implement value-adding techniques in their production management. Many companies begin their improvement efforts without considering the need for a comprehensive plan. As a result, their improvement efforts are not carried out in an integrated and complete manner and do not lead to complete and desirable results. The main objective of this study is to provide a framework that proposes a detailed vision of lean implementation in the machine-woven carpet industry, considering the value stream map as a tool to achieve improvement strategies in this industry. This framework... 

Organizations increasingly prioritize and utilize their intangible assets in a combined manner to achieve sustainable competitive advantage and success in a volatile market environment. In this research, the most important intangible assets of organizations have been identified. Using the Generalized Method of Moments, a suitable regression method for the statistical analysis of panel data, the impact of intangible assets on organizational profitability—specifically the return on assets—is examined separately and simultaneously across manufacturing and service industries. These assets include innovation, employee engagement, and customer satisfaction. The population of this study consists of... 

One of the challenges which increasing penetration of renewable energy sources with variable generation brings is the need for more flexibility in the power system. A promising way to overcome the challenge is to have local sources of the flexibility in distribution level. To this end, we present a new model for multi-stage distribution system expansion planning which jointly considers expanding the network assets and increasing the flexibility at local level by installing conventional dispatchable distributed generator units and energy storage systems. Demand response is also considered as another source of the flexibility which can be utilized by the system operator. Since deviating from...