Sharif Digital Repository

Wall systems are an essential part of the buildings and their capacity should be properly considered in their design. However, the seismic behavior of building systems with in-filled walls and their interaction is a very complex issue, yet to be understood. Using the in-filled walls in the buildings without including them in the design process changes the whole behavior of the structural system as well as their failure mechanism under earthquake excitations. On the other hand, there have been extensive researches on rehabilitation of the structures with in-filled walls or designing them as the main or one of the lateral load carrying systems against seismic input. In this research, first the... 

Because of mistakes in the design and calculation, incoherence between construction and design, structural changes, changes in loads and also damages caused by the passage of the time, concrete structures need to be improved and strengthened. Polymeric sheets reinforced by fibers (FRP), according to their appropriate characteristic, are more efficient for strengthening concrete structures. Most studies on confined columns refers to confined RC columns with FRP and less mentioned about prestressed columns. In this study, the behavior of prestressed columns is analyzed by modeling a case of prestressed column in a nonlinear analysis software. Samples of confined concrete columns with CFRP and... 

Low power and high speed analog-to-digital converters (ADCs) are the key elements of communication and computing systems. There are several ADC structures such as delta-sigma, flash, pipeline, and successive approximation register (SAR) for different applications, albeit SAR ADCs are natural candidates of onchip designs for their low power and scalability benefits. Nowadays, SAR ADCs are widely being used in low-power moderate-resolution applications which need several tens of MS/s to low GS/s sampling rates. By virtue of the technology scaling power consumption of digital parts of a SAR ADC is reduced significantly. As a result, in a SAR ADC the power consumption of the digital-to-analog... 

In previous studies, effect of certain parameters such as soil K0 on piled raft load sharing ratio α_pr was not considered. Here, α_pr is ratio of pile group load to total load. In this study, we consider the effect of pile length (L), pile spacing (s), raft thickness (t), raft modulus of elasticity (Er), pile modulus of elasticity (Ep), coefficient of lateral earth pressure, and pile concentration. Soil is undrained clay with typical properties. Raft is made of concrete and piles are cast in-place. Modeling is done in FLAC 3D. To determine the effect of these parameters we calculated load sharing ration of piled raft at 10 cm settlement which is typical for design. Based on the results of... 

Nowadays counting small particles and gathering their morphological information is widely used in many fields as medicine, engineering, etc. One of the best examples of this technology is counting and distinguishing different cells which are considered bioparticles. In this thesis a brief review of different particle counting methods is presented. Among these methods flow cytometry technology is chosen, because of its speed and accuracy. In flow cytometry method cells are conducted to the center of a transparent capillary by sheath flow technique; then laser beam is radiated to the cells. The intensity of the light scattered from the cells is used to determine cell type and count. In... 

Lightweight drilling cement plays a crucial role when drilling in low-pressure formations. In such conditions, the reservoir pressure is lower than the hydrostatic pressure of the drilling fluids, increasing the likelihood of fluid infiltration into the formation. Drilling cement has multiple functions, including securing the casing pipes, preventing fluid migration into the formation or from the formation into the wellbore. In low-pressure formations, special attention must be paid to the cement weight to avoid increased pressure that could lead to formation invasion. Lightweight drilling cement is formulated using low-density materials and lighter properties to prevent excessive pressure... 

In this research, numerical simulation of the impact of a drop on a flat surface with oblique velocity has been performed, using two-phase model of Lattice Boltzmann Method (conservative phase-field). During impact, it is important to investigate two-dimensional drop dynamics and to evaluate the effectiveness of the numerical method used. The model used here restores conservative phase field and preserves mass both locally and globally. In addition, to calculate the slope of the phase field, it calls the center points without engaging finite difference calculations. This makes it efficient for running parallel computations. A fixed dry and hard surface is considered and the drop impacts it... 

In this project Mordinate and Eu-1 zeolite were synthesized by hydrothermal method and then bifunctional catalysts including acid-base zeolite and Pt-Al2O3 metal base were mixed and made using a planetary mill. The modified catalysts were detected by various methods such as XRD, SEM, FTIR. The aim of this project is to synthesize and characterize the modified catalysts and to escalate their catalytic properties. Our focus is primarily on the synthesis of zeolite-based catalysts modified with unique features such as having active acid sites, high thermal stability and appropriate selectivity for the purpose of investigating the mechanism and kinetics of the C8 aromatic Compounds...