Sharif Digital Repository

“Progress” is among most frequently used terms in the past few centuries in public discussions, scientific communities as well as economic and sociopolitical policy making. This term has been used in our daily conversations so frequently that it seems to become an intrinsic goal for human beings. However, even a short survey of the introduced meanings of and suggested approaches to achieve “progress” during the last four centuries - since the term was first used- demonstrates that we are faced with a multitude of views from the different - and sometimes contradictory - schools of thoughts. Unfortunately, in recent decades, despite our national desire to “progress”, we have not yet thought... 

Cable-driven robots are referred to as parallel robots actuated with cables. In fact,in such robots rigid links are replaced by cables, which may be extended to desired lengths without making mechanism much heavy. This robot possesses a number of unique properties that makes it suitable for many industrial applications. The main factor which makes cable robots analysis different from other parallel robots is the incapability of cables to push objects. Hence, obtaining the workspace of a cable robot is one of the most important subjects associated with this type of robot.The goal of this thesis is to design a spatial translational cable driven robot, which may be used for object handling. For... 

Uncertain fuel prices and also global climate changes are accompanied by some state initiatives such as renewable portfolio standards (RPS). This has caused a fast growth in the amount of renewable energy installed worldwide especially wind energy over last decades. However, the intrinsic characteristics of wind farms output power, i.e. intermittency and volatility of wind speed along with being non-dispatchable in output generation of wind turbine raises many new technical and financial challenges for power system operators and planners. Up to these issues, large level of wind power penetration causes a growing concern in wind energy curtailment issue which the wind farm’s operator may be... 

One of the most important factors of reducing durability of concrete structures is corrosion of steel reinforcement in concrete. In this paper, corrosion behavior of reinforcing steel in concrete is investigated in two different methods of protection based on neural network. As regard the first method, pozzolanic additives with optimized percentage were added to Concrete mix design (the percentage of these additives are 25% Weight of cement of fly ash, Micro silica with 10 percent of weight of cement and 25% of Blast Furnace slag weight of cement). In the second approach of protection, 0/5 percent weight of cement of ferrogard 901 inhibitor is added to basic mix concrete design and the... 

One of the most important issues among defense is the increasing of the defense power using present facilities. Therefore, optimal setting and arrangement of equipment by considering different air-to-earth attack of enemy without knowing of properties and capabilities of available systems may not be possible. So, using defense equipment considering properties of them, and paying attention to existence restrictions and effective elements can have an effective role with the design of suitable algorithm.The main purposes of this thesis are: maximization of the efficiency of a defense system against. aerial invader targets, achieving the best arrangement of defense equipment based on suggested... 

In recent decades the use of FRP materials for strengthening structures has been developed extensively, thanks to their high strength, sufficient stiffness, high durablity, and ease of use. A great deal of research has been conducted on strengthening reinforced concrete beams and columns with FRP composites. By contrast, not many researches are performed on slabs, especially two-way slabs. In these few researches, the loading and boundary conditions are limited to simplest ones. Therefore, in this thesis, the focus of attention is on strengthening reinforced concrete slabs under various loads and boundary conditions using FRP composites.
In this thesis, first, FRP composites and their... 

In this research, an intelligent and integrated system for elderly fall detection monitoring based on CCTV cameras has been designed and implemented. The system consists of three main components: a fall detection device, a central server, and a mobile application. The fall detection algorithm runs in real time on a Raspberry Pi 4B board and combines classical methods with deep learning techniques. Specifically, an SVM model is employed in the classical stage, while Convolutional Neural Networks (CNN) and MoveNet models are utilized in the deep learning stage to enhance accuracy. To ensure security and privacy, the system incorporates end-to-end encryption and secure HTTPS-based... 

One of the key subjects in the area of mathematical optimization is a class of problems known as combinatorial optimization. We can find the optimal solution of continuous optimization problems feasible in time. But, in combinatorial optimization, we aim to obtain the optimal solution of the problem over a finite set. These problems are NP-hard and no polynomial-time solution has been proposed for this class of problems so far. Thus, in practical scenarios, we often use heuristic methods for solving NP-hard problems. There are lots of heuristic methods and choosing the best one in different situations might be challenging. In recent years, with the advances in deep neural networks,... 

Access to global memory is one of the bottlenecks in performance and energy in GPUs. Graphical processors uses multi-thread in streaming multiprocessors to reduce memory access latency. However, due to the high number of concurrent memory requests, the memory bandwidth of low level memorties and the interconnection network are quickly saturated. Recent research suggests that adjacent thread blocks share a significant amount of data blocks. If the adjacent thread blocks are assigned to specific streaming multiprocessor, shared data block can be rused by these thread blocks. However the thread block scheduler assigns adjacent thread blocks to different streaming multiprocessors that increase... 

In this dissertation we will study the problem of transmitting the information of continuous source over fading channel, especially when the transmitter does not have complete information about the channel status. In this situation we will have a tradeoff between the Quality of received packets and the Reliability in transmissions. To increase the quality of packets, for example, we should increase the quantization, and therefore, the transmission rates at the transmitter. But this will also increase the Error Probability at the receiver. It means that if the receiver gets the transmitted packet, it will have a better estimation of information source, but it is likely that error happens and... 

One of the most heatedly debated issues in Computer Science is Outlier Detection due to its vast and substantial applications such as credit cards, Image Processing,tax fraud detection, and medical approaches. Consequently, Outlier detection has been researched within various domains and knowledge disciplines. On the other hand, the research attempts have not been sufficient to overcome this critical problem considerably inasmuch as nearly all proposed techniques are associated with a special kind of applications or datasets.Firstly, this thesis attempts to provide a precise definition which not only excludes other one’s drawbacks, but also has its distinctive merits. Three essential... 

The objective of this project is numerical simulation of air flow and heat transfer between two horizontal concentric cylinders with rotation of inner cylinder and inertia of outer cylinder grooves on the inner cylinder. In this study, the air, meanwhile rotational motion by the inner cylinder will enter into the annular space between two cylinders with certain flow rate. It can be mentioned to cooling of power plant generators, Electric motors and rotating machines among usages of air flow between two cylinders. In this article the objective is calculation of pressure drop and Nusselt number, temperature distribution on the inner cylinder under conditions of constant temperature of... 

Tehran Refinery, as an industrial center that has significant water consumption in Tehran, intends to use the flow of water from the treatment plant south of Tehran after final preparation, with the aim of managing water resources and meeting its needs. And it uses a biological activated carbon (BACF) filter to reduce the DOC concentration. In these filters, the removal of organic matter is performed by the adsorption process as well as the biodegradation process by microorganisms grown on activated carbon. The presence of biofilm leads to continuous bio-regeneration of activated carbon during the water treatment process. Therefore, in this study, by examining the performance of these... 

Code clones are similar code snippets in software projects. Code clones, along with their disadvantages and applications, have long been studied by researchers. In recent years, due to the popularity of open source software, using software development ecosystems such as GitHub have increased dramatically. These ecosystems allow their users to perform high-quality software development without the need for physical presence. A number of previous studies have shown that software is being developed or modified repeatedly and many defects in software projects are duplicates. Finding these recurring codes and defects may be useful for software developers. Given that finding and fixing software... 

In the current era, the urgent need to reduce the use of fossil fuels and limit carbon emissions has highlighted the importance of shifting from traditional gasoline-powered vehicles to electric vehicles. The evolving landscape and challenges in the field of electric vehicles highlight the importance of ensuring the safety and reliability of energy storage systems. Lithium-ion batteries play a central role in electric vehicle technology, requiring thorough research efforts. Notably, the detection of internal short circuit, a common issue in lithium-ion batteries, has become a focus of researchers in recent years. This study aims to investigate the internal short circuit fault in lithium-ion...