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Energy, economic and environmental (3E) analysis of a micro gas turbine employed for on-site combined heat and power production
, Article Energy and Buildings ; Volume 42, Issue 2 , 2010 , Pages 259-264 ; 03787788 (ISSN) ; Mozafari, A ; Sharif University of Technology
2010
Abstract
This paper studies the optimization of micro turbine application to meet the electrical, heating and cooling loads of a building by energy, economics and environmental analysis. In this study following three cases are considered: 1: A simple micro gas turbine to meet the electrical power of the building. 2: A simple micro gas turbine to meet the electrical power of the building as well as the power required by heat pump and mechanical refrigerator needed for heating, cooling and domestic hot water (DHW) systems. 3: A CHP micro gas turbine to meet the electrical power of the building as well as part of the power required by heat pump and mechanical refrigerator needed for heating, cooling and...
Optical Injection Phase-Locked Loop Application in Continuous-variable Quantum Key Distributions
, Ph.D. Dissertation Sharif University of Technology ; Bahrampour, Alireza (Supervisor)
Abstract
The primary objective of this thesis is to provide solutions addressing some security loopholes in continuous variables quantum key distribution protocols. The coherent detection method is utilized in this particular quantum key distribution scheme, which is a phase-sensitive detection. To measure in the quantum noise limit in the detection part, we need a local optical oscillator, which must possess a high intensity and a consistent phase correlation with the quantum signal. Therefore, reconstructing the emitter’s reference phase in the receiver’s detection system is considered as one of the most critical challenges in these protocols. In order to attain this goal, in the early versions of...
Using Information Beyond Text to Generate Language Embedding Vectors
, M.Sc. Thesis Sharif University of Technology ; Sameti, Hossein (Supervisor)
Abstract
In this thesis, we introduce a novel Artificial Intelligence (AI) system inspired by the philosophical and psychoanalytical concept of imagination as a ``Re-construction of Experiences". Our AI system is equipped with an imagination-inspired module that bridges the gap between textual inputs and other modalities, enriching the derived information based on previously learned experiences. A unique feature of our system is its ability to formulate independent perceptions of inputs. This leads to unique interpretations of a concept that may differ from human interpretations but are equally valid, a phenomenon we term as ``Interpretable Misunderstanding". We employ large-scale models,...
Design and Fabrication of Microfluidic System as Concentration Gradient Generator
, M.Sc. Thesis Sharif University of Technology ; Saadatmand, Maryam (Supervisor)
Abstract
According to today’s medicine progress, the need for improving the medical facilities have been increased. Within the human body, the biomolecules concentration gradient is regulating the cell functions. Biological processes such as immune response, wound healing, and cancer metastasis have been affected by the bimolecular concentration gradient. So understanding the cell behavior in the presence of a chemical gradient can improve the understanding from these biological processes, and also would help in medical researches. On the other hand, finding the appropriate dose of the drugs and in some cases finding the most effective drug is a clinical challenge that made a new field of research in...
Selection of micro turbines to meet electrical and thermal energy needs of residential buildings in Iran
, Article Energy and Buildings ; Volume 39, Issue 12 , December , 2007 , Pages 1227-1234 ; 03787788 (ISSN) ; Bahadori, M. N ; Sharif University of Technology
2007
Abstract
Micro gas turbines are considered to meet the electrical, domestic hot water, heating and cooling energy needs of a residential building located in Tehran, Ahvaz and Hamedan. The building is 10 stories high and has a total of 8000 m2 floor area with the peak demands of electricity of 32.96 kW, DHW of 0.926 kW, heating load of 1590 kW and the cooling load of 2028 kW, when the building is located in Tehran. With these demands, 30 micro turbines of 30 kW (nominal power) are needed to meet all the energy needs of the building. The excess electricity generated by the micro turbines is to be used in a heat pump, and the energy in the exhaust gases is to be used to meet other thermal energy needs...
Internalizing the social cost of noise pollution in the cost analysis of electricity generated by wind turbines
, Article Wind Engineering ; Volume 30, Issue 6 , 2006 , Pages 521-529 ; 0309524X (ISSN) ; Bahadori, M. N ; Sharif University of Technology
2006
Abstract
The Social Cost of nuisance noise from a wind turbine is defined here as the additional cost to reduce the noise level at a receptor to an exceptable, non-nuisance value, i.e. to mitigate this cost. This acceptable sound level is considered to be 35 dB. Our example is a 10-kW (nominal power) wind turbine considered to supply the electrical energy needs of a 3-storey residential building in Tehran and Manjil. The turbine generates sound at 75 dB. To reduce the sound level at the third floor of the building to 35 dB, it was necessary to increase the height of the turbine from 24 m to 48 m. The initial installed cost of the turbine thereby increased from US$45.000 to US$55,000. The cost of...
Optimisation of micro gas turbine by exergy, economic and environmental (3E) analysis
, Article International Journal of Exergy ; Volume 7, Issue 1 , 2010 , Pages 1-19 ; 17428297 (ISSN) ; Ahmadi, A ; Ehyaei, M. A ; Sharif University of Technology
2010
Abstract
This research proposes a new method for optimisation of a power generation system based on exergy fuel cost and external social cost of air pollution. A thermodynamic model is provided to estimate the outlet mass flow rates of CO2, CO, NO and NO2 for a gas turbine based on maximising the first and second law efficiencies and minimising the objective function. Results show that inclusion of the external social cost of air pollution increases the optimum excess air ratio if temperature constraint due to metallurgical consideration is disregarded. Otherwise external social cost of air pollution is independent of optimised conditions
A new proof of FDR control based on forward filtration
, Article Journal of the Iranian Statistical Society ; Volume 19, Issue 1 , 2020 , Pages 59-68 ; Alishahi, K ; Shojaie, A ; Sharif University of Technology
Iranian Statistical Society
2020
Abstract
For multiple testing problems, Benjamini and Hochberg (1995) proposed the false discovery rate (FDR) as an alternative to the family-wise error rate (FWER). Since then, researchers have provided many proofs to control the FDR under dierent assumptions. Storey et al. (2004) showed that the rejection threshold of a BH step-up procedure is a stopping time with respect to the reverse filtration generated by the pvalues and proposed a new proof based on the martingale theory. Following this work, martingale methods have been widely used to establish FDR control in various settings, but have been primarily applied to reverse filtration only. However, forward filtration can be more amenable for...
Exergetic optimization of a PEM fuel cell for domestic hot water heater
, Article Journal of Fuel Cell Science and Technology ; Volume 2, Issue 4 , 2005 , Pages 284-289 ; 1550624X (ISSN) ; Abbassi, A ; Ehyaei, M ; Sharif University of Technology
2005
Abstract
In this paper, a 5 kW PEM fuel cell including burner, steam reformer, and water heater for domestic application has been considered. Water is used for cooling of the fuel cell. Cold water is passed through a cooling channel, warmed up and used for domestic water heating. To increase the efficiency, outlet steam of fuel cell is fed to the reformer. The perfomance of the system is optimized by exergy analysis based on the second law of thermodynamics. Also, the effect of burner, fuel cell temperature and stoichiometric air fuel ratio are investigated. In this analysis, pressure loss in the fuel cell and heat transfer of the cooling channel are taken into account whereas, pressure loss in...
Investigation of the Performance of Microbial Fuel Cell Based on Shewanella Bacteria with the Aim of Nanostructured Materials
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Sanaee, Zeinab (Co-Supervisor)
Abstract
The development of clean, renewable and alternative sources of fossil fuels has increased in recent years due to various factors such as environmental pollution, reduced fossil fuel resources and increased energy consumption. The application of microbial fuel cells is one of the clean energy production methods using renewable sources such as municipal sewage. The microbial fuel cell converts the chemical energy stored in organic materials into electrical energy and simultaneously purifies the sewage. Increasing current density and power density are the most important challenges for microbial fuel cells. In this study, the two biocatalysts of Shewanella Oneidensis MR1 and Escherichia coli...
Exergy, economic & environmental (3E) analysis of inlet fogging for gas turbine power plant
, Article Energy ; Volume 36, Issue 12 , December , 2011 , Pages 6851-6861 ; 03605442 (ISSN) ; Mozafari, A ; Alibiglou, M. H ; Sharif University of Technology
2011
Abstract
In the present paper, the effects of inlet fogging system on the first and second law efficiencies are investigated for a typical power plant (Shahid Rajaee) which is located near Ghazvin in Iran. Also a new function is proposed for system optimization that includes the social cost of air pollution for power generating systems. The new function is based on the first law efficiency, energy cost and the external social cost of air pollution for an operational system. Social cost of air pollution is based on the negative effects of air pollution on the health of society and environment. The economic aspect of these effects is called external social cost of air pollution. Other pollution sources...
Scattering Theory on Locally symmetric Spaces
, M.Sc. Thesis Sharif University of Technology ; Razvan, Mohammad Reza (Supervisor)
Abstract
Scattering theory on locally symmetric space first was studied by Peter Lax and Ralph Phillips. They studied the and develop scattering theory on it. Without the Fourier analysis tools this theory was completed with a lot of computations. In this thesis first we try to construct Fourier analysis by definition Fourier transform then by means of new tools we prove very short version of scattering theory on locally symmetric space . In general case for studying scattering theory we need firs spectral decomposition of Hilbert space of square integrable functions locally symmetric spaces of rational rank one is achieved by quotient of symmetric space where G is Lie group and K is maximal...
Performance Evaluation of Machine Learning and Deep Learning Algorithms in Psychiatric Disorders Classification Using the RDoC Clinical Dataset
, M.Sc. Thesis Sharif University of Technology ; Manzuri Shalmani, Mohammad Taghi (Supervisor)
Abstract
Today, psychiatric disorders have turned into a widespread epidemic worldwide. The World Health Organization estimates that one in every four individuals experiences a mental disorder at least once during their lifetime. Mental health problems not only directly affect the health of the affected individuals but also impose significant social and economic costs on the health system and society in terms of diagnosing and treating these disorders. Early, accurate diagnosis and effective treatment of mental health-related disorders can alleviate the suffering of individuals grappling with these illnesses. Machine learning methods are employed as a desirable solution for identifying mental health...
Silver nanoparticles supported on silica-coated ferrite as magnetic and reusable catalysts for oxidant-free alcohol dehydrogenation
, Article RSC Advances ; Volume 5, Issue 29 , Jan , 2015 , Pages 22503-22509 ; 20462069 (ISSN) ; Shakourian Fard, M ; Ehyaei, N ; Mahmoodi Hashemi, M ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Silver (0) nanoparticles supported on silica-coated ferrite were synthesized to be used as an efficient and recyclable heterogeneous catalyst for oxidant-free dehydrogenation of alcohols to the corresponding carbonyl compounds. The catalyst can be easily recovered and reused for 8 reaction cycles without considerable loss of activity. The facile recovery of the catalyst is carried out by applying an external magnetic device. The catalyst was fully characterized by the techniques of TEM, SEM, XRD, EDS, ICP-AES, and VSM. This journal is
Synthesis, Evaluation and Modification of Suitable Metal–Organic Frameworks (MOFS) for Desulfurization of Hydrocarbon Cuts
, M.Sc. Thesis Sharif University of Technology ; Khorashe, Farhad (Supervisor) ; Hajjar, Zeinab (Co-Supervisor) ; Soltanali, Saeed (Co-Supervisor)
Abstract
During fuel combustion, aromatic sulfur compounds in energy fuels convert into sulfur oxides, which cause major environmental problems such as acidic rain, global warming, and air pollution. Absorption desulfurization is one of the promising and economical methods to remove these sulfur compounds from fuels. Metal-organic frameworks (MOFs) are a class of nanoporous materials that are of interest for use as adsorbents due to their high specific surface area, unique surface adsorption properties, high adsorption capacity, tunable porosity, flexible dynamic behavior, and diversity in functional and metal groups. In this research, we first synthesized five metal-organic frameworks, namely...
Reduction of Sulfur Content of Model Feed by Oxidative Process in them Presence of Carbon Structures Based W-Mo Nanocatalysts
, Ph.D. Dissertation Sharif University of Technology ; Kazemini, Mohammad (Supervisor) ; Rashidi, Alimorad (Supervisor) ; Hajjar, Zeinab (Co-Supervisor)
Abstract
In this research, molybdenum and tungsten catalysts modified with cobalt and nickel on a carbon support have been synthesized and investigated in the oxidation desulfurization process. A model fuel was used to evaluate the synthesized catalysts. This model fuel was n-decane. dibenzothiophene was also used as a sulfur model. The synthesized catalysts were subjected to various analyzes such as XRD, FTIR, Raman, BET-BJH, NH3-TPD, TEM and ICP-OES for structural evaluation. On the other hand, synthetic parameters such as metal loading rate, molar or weight ratio of secondary metal (cobalt and nickel) to primary metal (molybdenum and tungsten) and molar ratio of citric acid to primary metal as...
Potential use of cold thermal energy storage systems for better efficiency and cost effectiveness
, Article Energy and Buildings ; Volume 42, Issue 12 , 2010 , Pages 2296-2303 ; 03787788 (ISSN) ; Mozafari, A ; Ahmadi, A ; Esmaili, P ; Shayesteh, M ; Sarkhosh, M ; Dincer, I ; Sharif University of Technology
2010
Abstract
The present article deals with the employment of combined heat and power (CHP) micro gas turbines using natural gas and cold thermal energy storage system (CTES) in Tehran (with mild climate), Bandarabas (with hot and humid climate) and Kerman (with semi-hot climate). A micro CHP produces electricity to meet the electrical energy needs of the building, and it is also considered to meet part of the heating, cooling and domestic hot water energy needs through a heat pump and refrigeration system. A detailed study considering the effect of CTES system on the selection of micro gas turbines of a residential building located in Tehran is performed. The results show that since the number of micro...
NOx Reduction from the Exhaust Gas of Marine Diesel Engines Using Non-Thermal Plasma
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Hamzehlouyan, Tayebeh (Supervisor) ; Hajjar, Zeinab (Supervisor) ; Khani, Mohammad Reza (Supervisor)
Abstract
Environmental regulations with respect to the marine diesel emissions have become stricter during recent years, thereby imposing traffic limitations on Iranian ships preventing them to enter emission control areas. Nitrogen oxides (NOx), as one of most important air pollutants, have adverse impacts on public health and ecosystem, so as the ships are the primary source of NOx internationally, the after-treatment system finds more urge to be developed. In this study, a NOx reduction system using non-thermal plasma technology is studied in order to determine its application and efficiency for NOx removal from the exhaust gas of Iranian marine diesel engines. Meanwhile, important factors were...