Sharif Digital Repository

Purpose of this research is to investigate the effects of different seismic isolation techniques and effect of their location on seismic behavior of assymetric bridges and on mitigating their seismic demand. According to different types of isolators and their possible locations, a research is necessary to help to choose the optimum choice among different possible choices for isolators and their location. In this strudy, Lead-Rubber Beraing (LRB), Friction Pendulum Systme (FPS) and High Damping Rubber (HDR) isolators have been investigated and 3D bridge models are 3-span concrete box girder with 50 meters long each span and each interior piers, 7 or 14 meters long. Isolators also can be... 

One of the main parts of peer-to-peer multicast is the structure of overlay network. Most of the existing works utilize some common parameters for constructing overlay tree. These parameters are bandwidth and delay. The mismatch between current overlay structure and underlying network topology causes severe link stress and then leads to high end to end latency. According to these problems, we propose a new overlay construction algorithm called OLT in this thesis that finds the location of peers and tries to connect peers that are as close as possible. OLT exploits a number of heuristic techniques to reach an optimized tree even in case of peer heterogeneity and high churn rate. Our... 

In the current century, an energy storage is one of the critical and important factors affecting on human life. Rechargeable batteries, specially Lithium ion batteries (LIBs), can be considered as ideal energy storage devices including various advantages e.g. high energy and power densities. In this work, Tin IV sulfide (SnS2) and its composites, making by conductive materials e.g. Reduced Graphene Oxide (SnS2@rGO), are prepared during two different synthesis methods consisting of Hydrothermal and Hot-bath, and their properties are investigated as anode material in LIB. The structural and electrochemical analyses demonstrated that the composite sample prepared by hot-bath method exhibited... 

Holography is a lensless process with a unique characteristic of recording a 3D image on a 2D plate! From the first hologram constructed by Gabor, the development of holography found several techniques. For the aim of fabricating holograms of Sharif University of Technology, International Campus-Kish Island’logo, we have chosen transmission and rainbow techniques because of their accuracy and applicability. A recording material is needed for the process. Photoresist was found more appropriate to work on. Besides He-Cd and He-Ne lasers are mostly in use in general holography. The laboratory work is an inseparable part which is achieved at laser and hologram unit of Atomic Energy... 

Conventional two-dimensional photos are images of a three-dimensional scene. In fact, since the recording medium record only the intensity of the incoming light, information about the phase of the light couldn't be recorded and this results in making 2D photos from a real 3D scene.
In this research a mechanism for getting three-dimensional images in endoscopy and laparoscopy by Digital Holography has been designed based on the criteria standards in this field.
 

In this study different kinds of solid phase microextraction fibers based on sol-gel technology were employed for extraction and pre-concentration of phenol in occupational air and oxadiargyl in plant and environmental samples. In the first work, a SPME method followed by on-fiber derivatization and gas chromatography-mass spectrometry detection (GC-MS) was developed for the analysis of phenol in the air. The application and feasibility of three different sol-gel based SPME fibers with different polarities, polar and non-polar poly (dimethylsiloxane) (PDMS) and polyethylene glycol (PEG), have been studied. Influential parameters such as fiber coating type, type of derivatization reagent,... 

In recent years, there have been many efforts for distributing a big and complex duty among some agents in order to do it more simply. Large number of these methods are in area called distributed systems, where several different agents start to work together to do a difficult or complex duty which each of them cannot do it lonely. Combination of distributed systems and artificial intelligence is known as distributed artificial intelligence.
One of the theories that has received attention recently, is called Embodiment. According this theory, in cooperation of a set of agents for performing particular task, expertise might not be integrated in a centralized controller, rather it gradually... 

Increasing the complexity of software systems, their ubiquitous presence in the human activities, and necessity to preserving the functional and nonfunctional requirements of the systems under an uncertain environment, increase the need for self-adaptive systems. A self-adaptive system changes its structure and behaviors in response to changes in its environment and the system itself. A key research challenge in the self-adaptive community is to guarantee that the system fulfills its requirements. This issue can be addressed by employing formal methods during the design of the software systems. However, the assurance techniques should be used during the execution of the system as well as the... 

Novel high-throughput device and their applications as the microextraction systems for pesticide multiresidue determination is the centre of this research. 96 extracting unit based on solid phase microextraction and micro-Solid phase extraction were constructed and applied for high-throughput extraction.
In the first work, a high-throughput SPME on 96-well plate together with gas chromatography-mass spectrometry was developed for the determination of pesticide residues in cucumber samples. A home-made Teflon block consisting ninety-six holes was constructed to 96 SPME fibers being positioned in. SPME fibers consisted of stainless steel rods with a 1.0 cm polydimethylsiloxane tubing... 

Assessment of existing jacket type offshore platform against environmental wave loading hazard is the central component of this work. Two general approaches exist in this context, deterministic and probabilistic assessment. In this study, a new probabilistic method (reliability analysis) to assess offshore structures under environmental loading (extreme wave) is introduced. Before describing this approach, several necessary elements such as collapse analysis, sampling methods and wave hazard analysis should be investigated. First of all, deterministic assessment of SPD2 platform located in Persian Gulf, which is the case study considered in this dissertation, is conducted utilizing... 

Thiomersal is an organomercury compound. This compound is a well established antiseptic and antifungal agent. It has been used as a preservative in vaccines, immuno-globulin preparations, skin test antigens, antivenins, ophthalmic and nasal products, and tattoo inks. Thiomersal is very toxic by inhalation, ingestion, and in contact with skin, with a danger of cumulative effects. It is also very toxic to aquatic organisms and may cause long-term adverse effects in aquatic environments.
Thiomersal's main use is as an antiseptic and antifungal agent in vaccines. In multidose injectable drug delivery systems, it prevents serious adverse effects such as the Staphylococcus infection that,... 

In this study, a new resorcinol-formaldehyde xerogel was synthesized based on sol-gel technology and employed as a sorbent for micro solid phase extraction (µ-SPE) of BTEX and some selected pesticides from aqueous samples.
In the first part, a µ-SPE method in combined with headspace solvent microextraction (HS-SME) along with gas chromatography- mass spectrometry detection (GC–MS) was developed for the analysis of BTEX in aqueous samples. In our knowledge, this is for the first time that these two different extraction methods has been coupled to maximize the advantage of each extraction method. Influential parameters such as the peristaltic pump flow rate, extraction volume, extraction... 

The purpose of the presented work entailed the development of a simple, high throughput sample preparation method for determination of a wide range of veterinary drugs at regulatory levels in milk, chicken meat and egg. pretreating the veterinary drugs include SPE pretreatment was combined with sample homogenization, acetonitrile and sodium sulphate salt extract and precipitate protein, n-hexane removal of fats, centrifugation and filtration. To proceed this goal, titania / octavinyl POSS (TiO2 / OVP) nanocomposite was prepared by sol – gel method and it was used to coat the surface of commercial cotton fabric. POSS supplies numerous organic and inorganic groups, facilitating the... 

In the recent years, development of new technologies in the field of cognitive science has made a huge effect on the people social life style. Facial expression imitation with applications in the design of human robot interaction (HRI) systems is an active area of research. In this study, we propose an approach using a humanoid social robot, The Alice, for real-time imitation of human facial expression. The facial keypoints of the user are extracted by using the Kinect sensor together with manipulated SDK 2.0 codes. Kinect output array are collected for each expression, then the training dataset is created with these output arrays. An accurate Artificial neural network (ANN), which has a... 

Veterinary medicines are extensively applied in food producing animals for the treatment of various bacterial infections, so the risk of occurrence of unwanted residues in animal-derived food exists, which may have adverse effects on human health by directly causing disease via low-dose exposure and indirect harm via antibiotic resistance. The major challenges in determination of these residues stem from the complexity of matrix, as well as polar differences and low concentrations of them. This work aimed to develop a screening and quantification method for benzimidazoles, quinolones and tetracyclines residues in egg, milk and chicken muscle. For this, the sample was extracted with... 

During the recent years, manufactures and industries have paid attention to occupational health and safety of their employees. Formaldehyde is known as a probable carcinogenic agent and its large consumption made industries to consider it as a risk factor for occupational health. At vaccine production industries, Formaldehyde is used as disinfectant and stabilizer. In this study, a solid-phase microextraction (SPME) method based on kinetic and equilibrium calibration strategies was developed for monitoring of formaldehyde in the biologics production areas. The application and feasibility of three different sol-gel based SPME fibers with different polarities have been investigated. Two... 

Nowadays, by increasing the applications of robots in military, industry and also home usages, researchers are looking for the most efficient algorithms to control the robots. As Prof. Zadeh presented the fuzzy systems in 1965 as a proper probabilistic logic, fuzzy control has been developed and now is one of the most applicable procedures in new aspects of controlling because of its less required computational capacity and more proper stability. Although the human like and quadruped robots are more applicable because of their coincidence with more difficult conditions compared to the wheeled robots, more complicated methods should be implemented to control them.The main subject of this...