Sharif Digital Repository

One of the problems presently facing the world’s major cities is transportation network congestion. Managing transportation system with costs far less than construction or expansion of the network is one general approach to reduce traffic congestion. In this context, conversion of some regular lanes to special lanes for High Occupancy Vehicles (HOV) and studying the effectiveness of this management policy is a matter of importance. The aim of the present study is to evaluate the effects of HOV lanes on network traffic and travel demand. For this purpose several networks with two classes of vehicles are used that have been modeled as a linear complementarity problem. The effectiveness of this... 

In recent years, leg pain is a consequence of inappropriate foot movement, which is an important health problem for us today. The health problems of the foot and the waist are due to wearing inappropriate footwear that is not designed for different activities. For example, Walking, long-standing on the feet, cycling and so on. A shoe insufflator is not suitable for walking, cycling, and standing. For designing an appropriate shoe insole for different activities, it is important to have a force determination profile for each person. This means that the insoles design shoes should be personal. A low-cost device has been designed, which can be used to measure the pressure on the sole of the... 

One of the novel methods of stabilization of nuclear waste is the use of vitrification technology. In order to stabilize high level wastes (HLLW) in glass, it is required that the elements are in their oxide form. Therefore, it is necessary to evaporate the waste and turn it into a solid form so that the elements can be converted into oxide form in the calcination furnace. Hence, one of the challenges of stabilization is the optimization of evaporation and calcination conditions. In this research, the parameters affecting evaporation were first investigated. Using laboratory measurements of application: temperature (110 to 180 °C), presence of nitric acid (0.5 to 4 mol/L), ratio of zirconium... 

This study used the emulsion liquid membrane method to investigate the extraction and separation of thorium from nitrate solution. According to the results obtained from the studies, Cyanex 272 was a suitable option for selectively extracting thorium. For simultaneous extraction and stripping of thorium from dilute aqueous solutions, an emulsion liquid membrane system consisting of Cyanex 272 as an extractant, Span 80 as a surfactant and sulfuric acid solution as a receiving phase (internal phase) was used. Emulsion liquid membrane method has high mass transfer flux due to high surface to volume ratio, which causes high extraction efficiency and fast transfer of thorium ions from its low... 

One of the most common spinal surgeries involves spinal fusion or vertebral fixation, which is used to treat various conditions such as intervertebral disc disease, scoliosis (lateral deviation of the spinal column), fractures, infections, or the presence of tumors in the spinal column. In this surgical procedure, the use of pedicle screws and titanium rods prevents motion and friction between two vertebrae. Screws may enter the vertebrae in the wrong position and angle, causing bone weakening, rupture of nerve roots or blood vessels, weakness or lack of sensation in some parts of the body, spinal cord injury, and in severe cases, paralysis of the patient. For this reason, fusion surgery is... 

Lithium is a soft, silvery-white alkali metal that is recognized as the lightest metal and the least dense solid element. The increasing demand for lithium, driven by the global shift towards electrification and sustainable energy solutions, has transformed this material into a crucial resource in the modern economy. Lithium has applications in various industries, including the nuclear industry. 6Li is used for the production of tritium, and 7Li, in the form of 7LiOH, is used to adjust the pH in light water reactors and as an anti-corrosion compound in fission reactors. In this study, the extraction of lithium from the aqueous phase using a Y-shaped microchannel was carried out, and the mass...