Sharif Digital Repository

In this project, first of all the Axiomatic Design approach, then the Scarf Repair and papers about it so far have been explained. Then Scarf Repair design with Axiomatic Design approach has been done and at the end a damaged plate sample has been repaired with developed way. Axiomatic Design is a systematic approach to design or judge existing designs for choosing the best design. This approach, says that a good design is the one that satisfys Independence and Information axioms. Independence axiom says that the better design is the one that its functional requierments are independent from each other and Information axiom says that from designs that satisfy the Independence axiom, the... 

The aim of this thesis is to introduce some algebraic topologies methods and apply them on fining the chromatic number of some famous graphs and also hypergraphs. In the first part, we will use a mixture of two well-known technics, Tucker lemma and Discrete Morse theory to find an upper bound for the chromatic number of s-stable Kneser for some specific vector s. to find the sharper upper bound, we will deviate our strategy and use another approach by finding an edge-labeling and apply some theorems in POSET algebraic topology. In this way, we also find a connection between Young diagrams and the numbers of spheres in the box complex related to Kneser graphs and hypergraph. Actually, we can... 

Fossil fuels provide the most needs of the world's energy, however, continues to lead to two key problems. The first problem is their limitation, and the second problem is the creation of serious environmental issues. Therefore, the need for renewable energy sources is felt more than ever.As an energy source, hydrogen is the lightest, most efficient and cleanest fuel. One of its unique properties is efficiency, the production of electricity by fuel cells through the electrochemical process, has far greater efficiency than of mechanical energy production from fossil fuels in internal combustion engines or energy production in thermal power plants. A fuel cell is a device that converts... 

The human action recognition is one of the most important concepts of computer vision in recent decades. Most of the two dimensional methods in this field are facing serious challenges such as occlusion and missing the third dimension of data. Development of depth sensors has made easy access to tracking people and 3D positions of human body joints. This Thesis proposes a new method of action recognition that utilizes the position of joints obtained by Kinect sensor. The learning stage uses Fisher Linear Discriminant Analysis (LDA) to construct discriminant feature space. Two types of distances, i.e., Euclidean and Mahalanobis, are used for recognizing the states. Also, Hidden Markov Model... 

The non-stationary nature of brain activity signals and their many inter-subject differences have created many challenges in the practical applications of emotion recognition based on electroencephalogram (EEG) signals, such as brain-computer interfaces. In such a way, the use of traditional classifiers in classifying these signals leads to a significant decrease in accuracy when applying the classifier to a new subject. Domain Adaptation methods seem to be an effective way to solve this problem by minimizing the difference between the EEG signals of different subjects. But in the basic techniques for domain adaptation, looking at all subjects' data in the same look causes the loss of a part... 

The most important issues in massive concrete structures such as concrete dams are the increase in temperature due to heat generated by the dam Hydration of cement in concrete. Internal restrains are created from thermal gradient between the surface and the interior of the structure. External restrains are created from connections between structures and foundation for obstruct the movement of concrete structures due to temperature change. External restrains and internal creates tensile stresses in the concrete considerable, which can lead to thermal cracks in the structure. To prevent or minimize the possibility of cracks are examined thermal studies for the design of reinforced concrete... 

Coding information data is one of the ways to prevent noise effect on the information bits, during passing communication channels. Coding data gives the possibility to detect and correct the data in the receiver. The LDPC codes which were first introduced by Gallager in the 1962 are forward error correction codes and can approach the Shannon’s capacity to within hundredths of a decibel.
In this project a modified algorithm for decoding these group of codes is introduced, which can achieve acceptable bit error rate, while it can have better throughput than the same implementations. This algorithm is implemented partial-parallel for IEEE802.11n standard in ASIC. It is shown that, it has... 

Electrochemical sensing of glucose has received paramount attention in recent years, particularly, the non-enzymatic glucose sensing is one of the trends in the whole biosensing world. In this research, synthesis and evaluation of a hybrid structure of vertical oriented nickel nanorod-reduced graphene oxide sheets as a non-enzymatic glucose sensor were performed. The 3D array of nickel nanorods was synthesized by electrodeposition of nickel sulfate electrolyte in track-etched polycarbonate template with 100 nm pore size and 6-10 μm thickness. The electrodeposition performed in various conditions, and the best result was achieved by application of potential of 3 V for 60 minutes. The shiny... 

In this project, a novel action recognition method, named Fisherposes, is proposed, which is improved by several space-time (spatio-temporal) methods afterwards. The proposed method utilizes skeleton data obtained from Kinect sensor. First, pre-processing is performed in which the scales of bodies are canceled and the skeletons become aligned in order to make the method robust to location, orientation, and scale of people. In Fisherposes method, every action is defined as a sequence of body poses. Using the training samples for the poses, a Fisher subspace is created which we name it Fisherposes. Moreover, a novel distance measuring function, named regularized Mahalanobis distance, is... 

Lab-on-a-chip devices have gained a lot of attention in chemical and biomedical analyses during the past two decades. These devices employ microfluidics basics and fundamentals to combine multifold laboratory processes in one single portable chip. The electric field has been often used in most microfluidics applications for the ease of sample control as well as become easily integrated to other chip components. Instabilities in microflows would occur when two fluids of different electric properties are exposed to an adequately strong electric field. Studying these electrokinetic instabilities is not only important for the fundamental studies but also for practical applications in micromixers... 

Advanced Persistent Threats (APTs), use hybrid, slow, and low-level patterns to leak and exfiltrate information, manipulate data, or prevent progression of a program or mission. Since current intrusion detection systems (IDSs) and alert correlation systems do not correlate low-level operating system events with network events and use alert correlation instead of event correlation, the intruders use low and hybrid events in order to make detection difficult for such detection systems. In addition, these attacks use low and slow patterns to bypass intrusion detection and alert correlation systems. Since most of the attack detection approaches use a short time-window, the slow APTs abuse this... 

Management and reservation of mine tailings are among the most important problems in today’s engineering. Among the different kinds of mine tailings, wet tailings are of the most critical ones due to their slurry shape. In addition to their different form of settlement than normal kinds of soil, they can easily transfer the pollutants through their base to the adjacent areas. Therefore, investigation of their sedimentation and consolidation processes is necessary. In this thesis, it has been tried to program a code according to the literature, in order to simulate the sedimentation and consolidation process of wet tailings. The mathematical method that has been used in the thesis for solving... 

In the present study, the coordination chemistry of an amino acid azacrown macrocycle ligand bearing one carboxylic acid arm (MA1) was investigated by employing NMR spectroscopy, crystallography and computational chemistry. MA1 was synthetized by the reaction of chloroacetic acid with the parent azacrown macrocycle and its purity was confirmed with 13C and 1H NMR for the first time. A new MA1 homologue, MA3 was also successfully prepared and characterized with NMR, mass spectrometry, and elemental analysis. NMR studies showed that MA1 binds to cadmium via the carboxylate arm in solution. Crystallographic studies showed that MA1 formed a one-dimensional polymer with cadmium, wherein the... 

Eliminating poverty, which is one of the most important objectives of countries, requires a deep understanding of the trends and dynamics of poverty and the distinction between chronic and transient poverty. However, given the lack of high-quality panel data, measuring movements in and out of poverty in developing countries is difficult. In this research, we build a synthetic panel by constructing a consumption model and estimating the first-round consumption of households surveyed in the second round. The analysis of Expenditures and Income Survey (HEIS) for 1398 and 1399 shows that almost 29 percent of urban and rural households were poor in both years. In female-headed households,... 

In building construction, a rigid vertical diaphragm is capable of transferring lateral forces from exterior walls, roofs and floors to the ground foundation in a direction parallel to its planes.[1] Refractory elements against lateral forces contain moment frames, shear walls or a combination of them. In this research, shear walls are discussed. Nowadays, in cities having old contexture, some of the buildings should be destructed. Thus, modern buildings should be built. Due to the limitation of adequate space and lack of symmetrical plan, buildings must be built in asymmetrical form. To design the structures with asymmetrical plan, it is necessary to study buildings with presence of... 

Energy management in buildings play an important role in minimizing the global energy consumption. Providing an optimal temperature in buildings and workplaces is a significant step toward the energy management, regardless of the local climate. Buildings account for 20-40% of the world’s total energy consumption, and this consumption is increasing in developed countries at 0.5-5% per annum.In various studies, energy consumption potential has been investigated using model predictive control (MPC) and system identification.In this paper, the building system is modeled as a gray-box model in which the formulas are developed using the heat transfer equation and the solar radiation heat is...