Sharif Digital Repository

Social learning approach in economic policymaking is introduced against conflict-based approach in the similar context. Helco, 1973 first studied the effects of such a learning in economic policymaking and said ”men collectively wondering what to do… Governments not only ‘power’… they also puzzle.” The important point in studying policymaking through social learning approach is paradigm shifts in peoples’ mental models. In this approach, policies are not only the result of conflict between different interests but also are the output of a learning process. In this research we first assume that social learning has not occurred in policymaking community and that individual learning has... 

Because of increase in use of cars in recent years, demands for parking spaces have also dramatically grown. To resolve this issue construction of multi-storey underground car parks has sharply increased. Due to the high level of contaminants emitted by cars in parking lots and also the continuous presence of humen within them, the control of pollution level and parking indoor air quality is a vital matter. Type of ventilation systems including modern and conventional used for ventilating parking lots and also exhaust and supply vents locations are the most important factors affecting contaminants distribution. Thus investigation the performance of the conventional and modern ventilation... 

Propylene is one of the key material in petrochemical industries. In recent years, as propylene demand increases, development of new methods alongside traditional ways in production of propylene seems essential. The production of propylene from methanol using zeolitic catalysts is as one of this new methods. This method in recent years has got attention. H-ZSM-5 zeolite is one of the best catalysts appropriate for this process. However, rapid deactivation is the main problem this catalyst at the present time. Therefore, more research in order to increase stability and lifetime has been performed. The uses of promoters are as one of the simplest improvement methods of H-ZSM-5 zeolite.... 

By continuously measuring blood pressure, we can prevent the irreversible effects of high blood pressure. With the traditional method of using a cuff, it is not possible to measure blood pressure continuously during the day, so for continuous monitoring of blood pressure, it is necessary to use a method without the need for a cuff. Based on previous studies, to estimate blood pressure, Photoplethysmogram and ECG signal features, or temporal and morphological features of Photoplethysmogram signal have been used. In methods that use ECG signals, signal recording is difficult, and methods that use both PPG and ECG signals are even more complex. Using only PPG signals also has its problems.... 

Cars with high center of gravity, such as SUV-Sport Utility Vehicles- have high tendency to roll over in high speeds and rapid maneuvers. An idea formerly proposed is to use a high speed rotating disc like a gyroscope on the onset of the rollover to exert a high stabilizing moment on the vehicle, and consequently prevent rollovers. Also using two counter rotating discs with opposite nutation will prevent interference with the car other degrees of freedom. To reduce the interference of the spinning discs with the vehicle dynamics, the discs are to be brought to speed by the action of a high accelerating mechanism during the rollover process(similar to the action of an airbag). This project... 

Reconfigurable devices are a popular platform invarious computational fields due to having high performance and flexibility and low non-recurring engineering cost. Generous flexibility of Look-up Tables (LUTs) in implementing arbitrary functions comes withsignificant area and performance overheads as compared with their Application Specific Integrated Circuit (ASIC) equivalent. One approach to alleviate such overheads is to use less flexible logic elements capable to implement majority of logic functions. In this thesis, we first investigate the most frequently used functions in standard benchmarks and then design a set of less-flexible but area-efficient logic cells, called Hard Logics... 

In this project photocatalysts TiO2, H3PW12O40, H3PMo6W6O40, H3PW12O40 / TiO2, H3PMo6W6O40 / TiO2, K2.5H0.5PW12O40, Cs2.5H0.5PW12O40, (NH4) 2.5H0.5PW12O40 and H3PW12O40 / M-TiO2 that M = La , Ce, Cr, Fe, Co were characterized by techniques DRS, FT-IR, BET, 31P NMR, SEM and XRD. The results of SEM and XRD particle size and page crystalline nanoscale catalysts, with size less than 40nm, respectively. FT-IR analysis confirmed the structure of heteropolyacid was produced. DRS analysis of the degradation reactions during wavelenght longer upheld. Degradation of methylene blue and pollutants such as Tinopal CBS-x to the polyoxometalates keggin is homogeneous and composite titanium dioxide two... 

Identification of dust storm hotspots using high resolution 1 km MODIS Aerosol Optical Depth (AOD) data obtained by MAIAC algorithm for a region including Iran and its neighbors, is one of the objectives of the present study. By implementing three important statistics on AOD and averaging over the last decade time period (2009-2019), dust sources of Iran, Iraq, Syria, Saudi Arabia, Oman, Afghanistan, and Pakistan were specified. These statistics include frequency of occurrence AOD>0.3, mean and coefficient of variation of aerosol optical depth. The membership rank of source zones in the set of hotspot areas has been obtained by applying the fuzzy logic approach on the three mentioned layers.... 

In this thesis, a method for predicting software defects in object-oriented web applications using deep learning is presented. Due to the increasing complexity of web-based software, such as e-commerce systems and financial businesses, maintaining the quality and reliability of these programs is of great importance. Software defects in such environments can lead to security problems, financial losses and loss of reputation of organizations. Therefore, an efficient method to predict and identify defects in the early stages of software development can help improve quality and reduce software development and maintenance costs. The proposed model in this research is a combination of... 

In this thesis, two kind of Kirchhoff type equations are investigated. for each of them we prove existence and uniqueness of weak solution by letting hypothesizes on problems functions and initial conditions and using Faedo-Galerkin method and some theorems in functional analysis. It is should be mentioned that one of the problems has unique strong solution according to compactness theorems. In the nest step stability of these equations are investigated. for this purpose it is showed that total energy of systems will tend to zero as time goes to infinity. Furthermore at the end of each chapter numerical results are presented to illustrate accuracy of obtained theoretical results. Finally we... 

The purpose of ranking Persian web pages is to retrieve the highest number of relevant documents related to the search query of Persian language users, with the minimum number of documents returned from the web. Information retrieval is one of the key issues in search engines. In this study, billions of documents were collected from Persian web pages, and due to infrastructure limitations, a few hundred million documents were indexed in a database like Elastic. Now, considering the user’s actual query, relevant documents should be retrieved from the indexed documents. To achieve this goal, a large Persian language model was needed. Existing large language models for Persian were not usable...