Sharif Digital Repository

Globally energy system is the main source of green house gas emission. 60-90 percent of manmade CO2 is due to energy sector. Pollutants like NOx, CO, Non Methane Hydrocarbons which may cause indirect effect on climate system are mainly emitting from energy sector. Gas, Oil and Coal extraction and transmission are responsible for more than 15% of Methane emission globally. Therefore it is important to consider all types of GHGs emission as well as all sectors of energy system to assess the GHGs mitigation potential throughout the energy system. Considering the significance of energy sector in GHGs emission, in this study we developed an optimized model for Iran’s energy sector in which we ran... 

The main goal of partake quake-attenuating in buildings is to absorb energy and to attenuate the exerted forces into structures as a result of ground motions. Notwithstanding achievements and developments in the field of dampers production, applying of dampers in structures is proportional to following complicated technology and subtle engineering. Installation and initiation of dampers depend on educated and expert crew; moreover, such attenuating systems need maintenance and repair during the useful structural life time. Therefore, nowadays civil engineering suffers from the lack of such quake-attenuating systems to be able to respond simply but applicable mechanism at the same time for... 

Scientific studies, conducted over the world, show that an immense portion of pollutants and greenhouse gases emission to the atmosphere are the direct result of the incineration of fossil fuels in industrial units. These industrial units include chemical industries, power plants, metal industry, etc. Therefore, there is a tremendous necessity to reduce the pollutants emission from these industries immediately and effectively. Meanwhile, in order to mitigate the emission to the atmosphere, there should be a meticulous estimation of pollutants emission from various sources. Hence, in a project called "standardization of emission of pollutants from diverse industrial units in Iran", the... 

Due to the physical limitations of the conventional 2D ICs at Giga-Scale Integration, modern technologies have been emerged. Among them, through silicon via (TSV) - based 3D ICs have been used to continue Moore’s law in the interconnect era. In these systems, dies are stacked at z-direction after wafer thinning. Electrical connections between stacked dies are done by TSVs. One important advantage of 3D integration technology is their ability to stack heterogeneous systems with different technologies on a single chip. This will not only increase interconnect density but also will reduce the delay and power consumption. However, nowadays, fabrication and optimum design of TSVs are still big... 

Climate change and energy security are key drivers for future energy policy. While energy security has been a pillar of energy policy for about a century, concern about climate change is more recent and is bound to radically change the landscape of energy policy. Policy makers are now under increasing pressure to address these twin challenges: to develop cost-effective policies that will both ensure the security of our energy system and reduce greenhouse gas emissions.
Main Effort in this Project is to construct an integrated model of Iran’s energy system to serve as a policy analysis tool, by which policymakers are able to identify the future effects of a wide range of policies in... 

Liquefaction induced lateral spreading is defined as the lateral displacement of mildly sloping grounds or those ending in free faces as a result of liquefaction in subsurface soil layers. Damages imposed by lateral spreading on pile foundations supporting different types of structures such as ports, bridges and buildings are usually observed in large earthquakes. These potential damages are of high degree of importance in southern and northern coastal areas of Iran where several ports and critical facilities are located. River banks all over the country where bridge piers exist are also among the areas prone to potential damages. Evaluation of the effects of lateral spreading on existing... 

The release of toxic materials causes tragic accidents every year. There are various techniques in order to mitigate the release effect of these materials such as Application of air jets, steam curtains and water curtains. In this study first, previous works are reviewed in order to select the best technique for the mitigation of heavy toxic gas release. Then CFD modeling is used to simulate this technique.
A field situation in which chlorine gas was released upwind of water spray was simulated using the open-source software FDS (Fire Dynamic Simulator), a CFD model. Only mechanical effects of water sprays are considered; hence the effect of absorbtion is neglected. Finally tha... 

Oil and gas industries are always considered as one of the most polluting industries in the world. Many pollutants are emitted from the industry into the environment every year. Equipment’s leak and flaring off additional gases produced by various processes of oil and gas production are the main sources of waste in these industries. In order to control these hazardous wastes, it is necessary to provide effective solutions and make appropriate decisions so policymakers will be able to implement policies in order to reduce the emissions of air pollutants. In order to reduce the emissions, it is necessary to conduct the correct and reliable methods and have sufficient information about the... 

Expansion of using social networks for reading and sharing news on the one hand, allows for quick and easy access to the news, but on the other hand, increases the spread of fake news and misleads many users. Therefore, identifying the fake news and attempting to mitigate its spreading on social networks is one of the major research areas in recent years. An important issue in this regard is reducing the time gap between news release time and identifying it as fake and starting to take action. Many researches has been done on detection of fake news, but since there is a trade-off between minimizing the time gap and maximizing accuracy, work on these models continues. There are also different... 

Release of toxic gases and hazardous materials is very dangerous for health of people that presence in near of release places. Whereas if the concentration of some toxic materials is more than a definite limit, it may cause of irreparable hurt to health of people in very short times, hence reduce the concentration of released materials can get the time for refuge in safe sites for people that presence in released site in initial times.
In this paper with use the Computational Fluid Dynamics models the effect of fence in reduce the concentration of dense gases and delay the distribution of these gases has been studied. The two toxic gas (chlorine and methyl-isocyanate ) have been... 

Annually Natural disasters make tremendous impacts on societies. Fatality rate of earthquake in Iran is almost more than all other disasters. There are numerous problems in disaster Management's of Iran and other countries. One of the disaster Management's phases is response phase which mostly depends on emergency processes, so most of papers working on this phase, plan for emergency state by using different techniques.All the studies seeking the response phase, try to reduce the loss of disaster by the use of immediate response to earthquake, pointing the disaster after occurrence. But Another point of view is to make loss reduction by precautious activities and plans. Actually, the loss... 

Use of nano-scale VLSI technologies in the fabrication of System-on-Chips (SoCs) makes reliability as one of the major issues in the design and implementation of these products. SoCs are susceptible to several fault sources such as crosstalks, cosmic particle strikes, electromagnetic interferences, and power supply disturbances. Among the mentioned fault sources, crosstalks have the major contribution in threatening the reliability of SoCs. This thesis addresses the modeling and mitigation of crosstalk faults. In this regard, two analytical models and three crosstalk reduction methods have been introduced. The proposed analytical models, which have been introduced in the fourth chapter of... 

In this research, a multigeneration system was designed and evaluated, utilizing solar and geothermal energy to generate electricity, fresh water, hydrogen, and oxygen. The system's performance was assessed from energy, exergy, and economic perspectives. The setup involves a solar tower contributing energy to the gas cycle and a geothermal well supplying preheated water for the steam cycle. The system employs a molten salt cycle to capture heat from the solar receiver, transferring it to the air cycle. The remaining energy requirement is met by the Air Brayton cycle, which combines methane and hydrogen as fuels within the combustion chamber. Additionally, a steam cycle is integrated to...