Sharif Digital Repository

Aspect-Oriented Software Development (AOSD) concentrates on separation of global cross-cutting concerns, or aspects. The weaknesses of Object-Oriented Software Development (OOSD) in localizing orthogonal concerns simultaneously leads to distributing them across several modules, and thereby creating modules that have to deal with various concerns. This usually results in poor modularization and difficulties in tracing certain requirements (especially nonfunctional requirements) to their implementations. The AOSD approach determines the common aspects that exist across modules created through OOSD, and modularizes them. Thus, AOSD takes the next step in creating modular software. Applying this... 

In this thesis, a power switch with a smart driver is designed. 4-ampere current can pass through the switch, and the driver is capable of switching the load with 50 kHz frequency. The smart driver consists of an internal oscillator, internal regulator, charge pump, current limit, a level shifter, overtemperature and over/under voltage circuit. All these circuits are designed and developed in high voltage BCD 0.18 um process and well discussed in the thesis. All four kinds of protections are designed and implemented; open load detection, short circuit detection, over temperature shut down, UV and OV detection. Charge pump idea is used instead of the bootstrap method, which makes it possible... 

This thesis proposes a probabilistic framework for evaluating and enhancing the community recovery process following an earthquake occurrence. This framework serves as a recovery decision support tool, aiming to enhance community resilience through the optimal allocation of limited available resources following a disaster occurrence. To this end, Bayesian network and agent-based simulation are integrated, each of which forming one of the modules of the proposed framework. The first module, namely, the Bayesian network, leads to situational awareness of the status of the community after the earthquake by fusing data from various sources. The data, such as the earthquake event characteristics... 

The purpose of this study is to investigate the distribution of air flow and temperature in electric machines. The fluid flow equations are solved by using the characteristic Galerkin. The unsteady equations of the air flow and heat transfer between the rotor, stator and radial cooling channels of the generator are solved by finite element method. Tetrahedral elements are used, but hexahedral elements can also be used. The upwind method is used to discretize the convection terms, but the central difference for the diffusion parts, that is equal to Petrov-Galerkin method in steady state situation. Due to the large number of channels and specific geometry, to reduce the computation costs, the... 

Nowadays, advanced and inexpensive pre-clinical methods for investigating the effects of anti-cancer drugs are expanding. One of the latest three-dimensional laboratory modeling for evaluating the effects of drugs is the use of tumor-on-chip technology, which actually models the physiological system of the body through three-dimensional scaffolds, multicellular cultures, and shaped vascular systems. In this study, three-dimensional culture of cancer cells was performed in the form of spheroids. A chip of U-shaped microstructures with and without gaps was used to trap cells and form cancer spheroids. We simulated the simultaneous effect of drug and oxygen concentration distribution inside the... 

A high percentage of reinforced concrete buildings are not earthquake resistant because they are often designed based on old regulations, which do not satisfy the requirements of new earthquake codes. Construction weaknesses make buildings more vulnerable, and thus, different approaches are needed to strengthen structures to resist lateral forces. 3D Panel system brings together the best qualities of in-situ and precast systems and improves their shortcoming. It includes the advantages of precast systems, such as having relatively low labor costs, less waste material and machinery, reducing implementation time and improving quality control. At the same time, serious problems related to... 

Using single RAID HW-Controller in data storage systems can become a single point-of-failure. Hence, it will affect system availability. As a result, in enterprise-class storage systems, utilizing dual-HW-Controller architecture for managing redundant array of independent disks is prevalent to enhance performance and reliability. Employing such architecture, however, faces major challenges. One of these challenges is the synchronization of dual-HW-based controllers in case RAID arrays revealing erratic behaviours. No thorough study has been done for evaluating dual-controller architecture synchronization mechanisms and its performance. In this thesis, different configurations of enterprise... 

Modeling and performance evaluation of the real time distributed systems is a significant problem. Stochastic activity network is one of the high level models used for this purpose. This network is an extension of generalized stochastic Petri net which is more powerful and flexible than other Petri net extensions. Checking the satisfiability of properties such as performance, dependability and user's expected properties is considerable in these models. Thus, using the approaches and generating modeling and model checking tools with the mentioned purpose is attractive. A model checker automatically checks the correctness of the system behaviors as properties against the model by getting the... 

This study has focused on the important problem of landing on a planet as an important current and future space mission. In this regard, dynamics modeling and integrated state estimation and control problems have been investigated in different views. To this aim, first a novel concurrent representation for translational and rotational kinematics has been developed based on the extension of modified Rodrigues parameters to dual space. This parameter set, called dual modified Rodrigues parameters (DMRP), is then utilized to establish an integrated roto-translational dynamic. The proposed DMRP-based kinematics and dynamics have been verified via comparison to traditional methods of... 

Prevalent deployment of Distributed Energy Resources(DERs) in the demand side of electrical energy grids has several advantages such as greenhouse gases emission reduction, mitigation of power losses in the distribution grids and abatement of the dependency on the wholesale generation companies. At the same time, it paves the way for the advent of local interactive energy trading frameworks. In the following thesis, a distributed data-driven algorithm is developed for market-clearing in a community-based local energy market. The social welfare maximization is considered as the objective of the energy trading. The production and demand of electricity are the decision variables of sellers and... 

Understanding biological systems requires extensive knowledge of individual parameters, and to study the processes of cell differentiation and cell behavior, a suitable environment must be created with the physiological conditions of the human body. For this purpose, with the knowledge of microfluidics, a microenvironment can be provided to study the behavior of cells on a small scale. The use of bone tissue model microfluidic chips is an alternative and new method in which it is possible to study the behavior of cells to differentiate into bone and to examine the toxicity of drugs, which in itself can help in the effective and successful treatment of these cases show. Therefore, in this... 

The main topic of this research is the navigation and control of a free-flying satellite with a robot manipulator while transferring and placing cargo on a space station. After connecting the cargo module, astronauts and robots need to deliver the available loads to the desired modules in a space station. Capturing an object or cargo is a critical issue studied extensively so far. However, delivery and placing of the cargo at the target point have not been investigated yet, to the best of the author’s knowledge; hence, this is a primary motivation for conducting the proposed research. After capturing the payload, the position and attitude of the manipulator with respect to the station’s... 

Cardiovascular disease (CVD) currently remains a considerable challenge for clinical treatments. CVDs account for N17.5 million deaths per year and will predictably increase to 23.6 million by 2030. The main purpose is to create human model systems to study the effect of disease mutations or drug treatment on the heart. In addition, engineered cardiac tissues are considered promising candidates to be transplanted to improve the function of diseased hearts. For engineered active tissues/organs, 3D bioprinting can fabricate complex tissue architecture with a spatiotemporal distribution of bioactive substances (cells, growth factors, and others) to better guide tissue regeneration. However,...