Sharif Digital Repository

FPGA is a suitable substrate for implementation of embedded systems, mobiles, and hand-held devices due to cost reduction for \emph{Non-Recurring Engineering (NRE)}, short time to market, design flexibility, and reprogramming capability. Significant downscaling of CMOS technology feature size has led to static power growth rate, which is a limiting factor in further scaling. Previous studies aimed at reducing power consumption, mainly have focused on the power consumption of logical resources. However, proposing a low power architecture in routing network affects the power consumption of FPGAs significantly, because of the dominant power consumption in the routing network. This thesis... 

The hand is an important part of the human body, the loss of all or part of it greatly reduces a person's ability to perform daily tasks. For people who have lost this significant organ, replacing it with an artificial limb that can meet some of their needs is essential. Today, all robotic prostheses use electromyographic (EMG) signals from the remaining muscles of the disabled limb as input signals. Classifying the EMG signal and converting it to a control signal faces serious challenges. Variation of signal properties over time, electrode slippage, muscle fatigue, changes in muscle contraction intensity, and changes in limb position and direction are some of these challenges. Therefore, a... 

Lipopolysaccharide (LPS), also known as endotoxin, is a highly toxic component exists in the outer membrane of gram negative bacteria. It releases into the environment during every phase of bacterial growth cycle, so it causes contamination of a wide range of biopharmaceutical products. Even small quantities of endotoxin injected to human body can result in fever, septic shock, and death. Therefore, it is highly important to detect and also quantify endotoxin of biopharmaceutical products in quality control laboratories. The most validated method used for endotoxin detection is Limulus Amebocyte Lysate (LAL). Although this method is sensitive, it has some unavoidable drawbacks such as highly... 

Permeability is an essential parameter used for reservoir evaluation, simulation and management to optimize oil recovery. The conventional approach to estimate reservoir connectivity, conductivity, sweep efficiency and other critical information for decision-making is to build detailed geological models, which are then upscaled to a coarser grid where flow simulations are run. However, this takes many hours to be carried out even for a single realization practically. In practice, a very small number of realizations are considered and consequently the true uncertainty in the results is very poorly estimated. In this study, a statistical model of isotropic overlying sandbodies is used to... 

One of the major reasons causing cracks in external surfaces of concrete arch dams are thermal loads. Therofore, in order to avoid instabilities due to function of thermal loads in association with hydrostatic and hydrodynamic pressures, a precise evaluation of temperature distribution through dam body is indispensable. In this study, effects of thermal loads mostly on upstream surface of Karun-3 concrete arch dam in Iran were examined using a 3-D finite element method considering water level fluctuations. Also the influence of operatvie boundry conditions in our problem which are water temperature, air temperature and solar radiation was precisely taken into account. Moreover, nonlinear... 

Pile foundations suffered severe damages during the past earthquakes in all around the world. These damages were more severe in laterally spreading grounds and they mostly have been observed in gently sloping grounds and coastal areas. In these cases, Pile foundations not only are subjected to structures inertial loads and kinematic loads of liquefied soil but also lateral spreading intensifies damages. Thus, in the recent decade, several researches have been conducted to investigate the behavior of pile foundations in liquefiable and laterally spreading grounds, however, some uncertainties still remain in modeling of soil-pile interaction. In this study, the effects of liquefaction- induced... 

Loads from laterally spreading ground have been a major cause of damages to pile foundations in past earthquakes. Analysis of case histories have shown that damages are particularly intense when a nonliquefiable surface crust layer spreads laterally over underling liquefied layers. In this research the effect of lateral spreading due to liquefaction on single piles embede in a gently sloping ground has been investigated. Finite element method using OpenSees is used to model the pile and embedded soil. The soil profile for all models consisted of a nonliquefiable crust layer overlying loose sand with Dr = 30-35% overlying dense sand with Dr = 70-80%. The effect of geometric properties such as... 

Initial static shear stress caused by slopes or nearby structures' foundations can affect the behavior of the soil which is concerned many investigators during previous three decade. In this investigation, the effect of initial static shear stress on the liquefaction resistance of Babolsar sand has been probed using cyclic simple shear tests. Three different initial relative densities (Dr0=20%, 40% and 60%) and three different initial normal stresses (σv0= 50, 150 and 250 kPa) were considered in tests and four various initial static shear ratios (α) ranging between 0.0 and 0.3 were applied which leads to more than 190 distinct experiments. All tests were conducted under constant volume and... 

In this research, the effects of Rayleigh waves on the response of typical three-dimensional concrete faced rock-fill dams (CFRDs), considering dam-foundation interaction and spatial variability of earthquake ground motion are investigated. The time history of Loma Prieta earthquake (Gilroy 1 station) is used as input excitation. The dam is considered to be located in a prismatic canyon with trapezoidal cross-section. A substructuring method, in which the unbounded soil is modeled by the scaled boundary finite-element method (SBFEM), is used to obtain scattered motion and interaction forces along the canyon. Non-linear model is used for rock fill... 

In this project rotational barrier around the C-N bond in 4-ethyle-morpholine- carboxylate has been studied using DNMR spectroscopy. Spectra were taken at variable temperature, and then with simulation of bandshape broadening pattern at coalescence region, rate constants of exchange were obtained for all temperatures. For simulation of line-shape broadening Spinworks software was used, that with two interfaces made possible simulation with two bandshape simulator programs, DNMR and MEXICO. The rate constants obtained from simulations, were used for calculation of thermodynamic activation parameters (∆G#, ∆H#, ∆S# and Ea). ∆G# 298 value of 13.66 Kcal/mol for 4-ethyle-morpholine- carboxylate... 

Soil liquefaction is a phenomenon in which soil loses much of its strength or stiffness for a generally short time but nevertheless long enough for liquefaction to be the cause of many losses. Thus, many researchers have worked on the factors which affect this phenomenon. Effects of initial static shear stress on liquefaction strength of loose and medium dense Babolsar sand specimens were investigated in this study. Babolsar sand is fine to medium uniform sand classified as SP in USCS. Tests were performed with cyclic simple shear and static triaxial devices. All tests were performed under consolidated undrained conditions. Cyclic simple shear tests were performed under constant vertical... 

The Barrier of the internal rotation around C-N bond in O-ethyle morpholine-4-carbotioate were calculated using dynamic NMR spectroscopy (DNMR) in DMSO solvent. 1H and 13C NMR spectra were recorded at different temperatures (295-350K). Band shape broadening patterns at coalescence regions were simulated to extract rate constants of NMR spectera. Transition state thermodynamic properties of internal rotation around C-N bond in O- ethyle morpholine -4- carbotioate are estimated: , , , . To assay reliability of the estimated values, transition state thermodynamic properties were calculated using PCM model at method and basis set B3LYP/6-311++G(d,p). Theoretical values of thermodynamic... 

Accurate prediction of relative permeability for various reservoir rocks at various saturation conditions has been of concern for a long time in petroleum industry. Relative permeability is known as one of the most significant parameters in simulation of actual multi-phase flow through porous media during life-time of a hydrocarbon reservoir. In addition, it plays important role in oil production and well completion. Direct experimental measurement in order to determine relative permeability of porous rock has long been recorded in petroleum related literature. However, empirical methods for determining relative permeability are becoming more widely used, particularly with the advent of...