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    Performance prediction of twin-entry turbocharger turbines

    , Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 29, Issue 2 , 2005 , Pages 145-155 ; 03601307 (ISSN) Ghassemi, S ; Shirani, E ; Hajilouy Benisi, A ; Sharif University of Technology
    2005
    Abstract
    In this paper, the performance of the twin-entry radial flow turbine under steady state and partial admission conditions is modeled. The method, which is developed here, is based on one-dimensional performance prediction. In one-dimensional modeling, the flow properties are assumed constant on a plane normal to the flow direction. This assumption is in contrast with the flow at the rotor entry of a twin-entry turbine under partial admission condition. In this study the one-dimensional performance prediction method for a single-entry turbine is modified to analyze the twin-entry turbine. In particular, the loss coefficients due to friction, clearance and blade loading, which are already... 

    Development of an integrated computer environment for optimization of engine management system calibration

    , Article 2004 SAE World Congress, Detroit, MI, 8 March 2004 through 11 March 2004 ; 2004 ; 01487191 (ISSN); 0768013194 (ISBN); 9780768013191 (ISBN) Vossoughi, G. R ; Rezazadeh, S ; Sharif University of Technology
    SAE International  2004
    Abstract
    In this paper, development of a MATLAB-based computer environment for optimization of EMS calibration is presented. The objective is to eliminate the complicated and tedious calibration process on chassis dynamometer or at least reduce the time required. In this way, first a black-box model of engine is developed. Then this model is linked to ADVISOR -The renowned vehicle simulation software- to obtain an integrated engine-driveline model. This model is used in the optimization process, which includes different optimization techniques. Copyright © 2004 SAE International  

    The proceedings of the Fourth International Conference on Civil Engineering; May 4-6, 1997, Sharif University of Technology, Tehran, Iran

    , Book International Conference on Civil Engineering (4th: 1997: Tehran, Iran) ; Sharif University of Technology. Dept. of Civil of Engineering
    Sharif University of Technology  1997
    Abstract
    v.1. Structural engineering and earthquake engineering.-- v.2. Geotechnical engineering.-- v.3. Transportation, civil engineering materials, construction management.-- v.4. Water resources and environmental engineering, surveying and mapping  

    Catalytic converter reducing dual fuel (natural gas/diesel) engine emissions

    , Article Scientia Iranica ; Volume 6, Issue 5 , 2000 , Pages 75-81 ; 10263098 (ISSN) Sallamie, N ; Kazemeini, M ; Soltanieh, M ; Checkel, M. D ; Badakhshan, A ; Zheng, M ; Mirosh, E. A ; Sharif University of Technology
    Sharif University of Technology  2000
    Abstract
    Using natural gas combined with diesel fuel in diesel engines provides a considerable contribution to modern industrial societies in order to control air pollution and, also, generalize and facilitate the use of public vehicles. In spite of the attractive features of this idea, including reduction of NO(X) and particulates, there is an important burden imposed upon the system at low to intermediate torques, namely high concentration of CO and unburned total hydrocarbons (THC), mostly composed of methane. In this work, based upon the oxidation of CO and unburned HCs and through experimental results, application of a monolithic oxidizing bifunctional catalytic converter as a novel... 

    The effect of superparamagnetic iron oxide nanoparticles surface engineering on relaxivity of magnetoliposome

    , Article Contrast Media and Molecular Imaging ; Volume 11, Issue 5 , 2016 , Pages 340-349 ; 15554309 (ISSN) Khaleghi, S ; Rahbarizadeh, F ; Ahmadvand, D ; Malek, M ; Madaah Hosseini, H. R ; Sharif University of Technology
    John Wiley and Sons Ltd  2016
    Abstract
    The purpose of this work is evaluating the effect of ultra small superparamagnetic iron oxide nanoparticles (USPIONs) coatings on encapsulation efficiency in liposomes and cellular cytotoxicity assay. Moreover, we assessed the effects of surface engineering on the relaxivity of magnetoliposome nanoparticles in order to create a targeted reagent for the intelligent diagnosis of cancers by MRI. For estimating the effect of nanoparticle coatings on encapsulation, several kinds of USPIONs coated by dextran, PEG5000 and citrate were used. All kinds of samples are monodispersed and below 100 ± 10 nm and the coatings of USPIONs have no significant effect on magnetoliposome diameter. The coating of... 

    Near field differential interference contrast microscopy

    , Article Scientific Reports ; Volume 10, Issue 1 , 15 June , 2020 Heydarian, H ; Yazdanfar, P ; Zarif, A ; Rashidian, B ; Sharif University of Technology
    Nature Research  2020
    Abstract
    Near field scanning optical microscopy exploiting differential interference contrast enhancement is demonstrated. Beam splitting in the near field region is implemented using a dual color probe based on plasmonic color sorter idea. This provides the ability to illuminate two neighboring points on the sample simultaneously. It is shown that by modulating the two wavelengths employed in exciting such a probe, phase difference information can be retrieved through measuring the near field photoinduced force at the difference of the two modulation frequencies. This difference in frequency is engineered to correspond to the first resonant frequency of the cantilever, resulting in improved SNR, and... 

    Change-request buffer role in configuration management process

    , Article International Conference on Software Engineering Theory and Practice 2010, SETP 2010, 12 July 2010 through 14 July 2010 ; 2010 , Pages 130-133 ; 9781617820731 (ISBN) Salajegheh, A ; Rastegari, Y ; Sayadiharikandeh, M ; Rastegari, S ; Sharif University of Technology
    Abstract
    CMMI is a unified model for software and system engineering in organizations. The initial CMM has been designed for software development. According to its successes, different models were developed by different groups such as: SECM, SACMM, IPDCMM, and FAAICMM. CMM Integration was introduced due to some problems such as lack of uniformity, overlapping, and incompatibility of mentioned models. Current paper is a research on CMMI, especially on configuration management process. We believe that accepting all change requests lead to ad-hoc versions and rejecting them lead to customer dissatisfaction. Therefore a Change-Request buffer is needed in configuration management process based on CMMI... 

    Emphasizing experiences in teaching software engineering courses

    , Article ICETC 2010 - 2010 2nd International Conference on Education Technology and Computer, 22 June 2010 through 24 June 2010 ; Volume 2 , 2010 , Pages V2149-V2153 ; 9781424463688 (ISBN) Mirian Hosseinabadi, S. H ; Aghakasiri, Z ; Sadeghi, A ; Delfani, P ; Ghandehari, M ; Sharif University of Technology
    Abstract
    Using software products as engineering artifacts is becoming more widespread in industry. It leads to increasing the need for training students and experts in the academic centers with software developing skills in accordance with the engineering principles and disciplines. However, one of the main challenges in the software engineering education is how to teach engineering disciplines to the students so that we can inspire the engineering concept to them. To do so if we use educational methods for teaching this course, which can show the usage of engineering disciplines to the students in practice and demonstrate the impact of their application on creating the engineered software products,... 

    The role of geotechnical engineering in sustainable and resilient cities

    , Article Scientia Iranica ; Volume 23, Issue 4 , 2016 , Pages 1658-1674 ; 10263098 (ISSN) Haeri, S. M ; Sharif University of Technology
    Sharif University of Technology 
    Abstract
    Geotechnical engineering is a fundamental subject in civil and environmental engineering that engineers are required to refer to when any type of retrofitting, design or construction of projects and developments are encountered in a city or in a rural area. Indeed in many projects like geotechnical structures, such as earth dams, geotechnical engineering is the main subject. In this paper, the role of geotechnical engineering in sustainable and resilient cities is elaborated mainly through a series of questions and answers. Also, some related geotechnical engineering research, that is in hands in Civil Engineering Department of Sharif University, is discussed in this paper. A unique... 

    Analysis of an engine mounting structure of an aircraft with the purpose of accurate adjustment

    , Article 2nd International Conference on Mechanical and Aerospace Engineering, ICMAE 2011, Bangkok, 29 July 2011 through 31 July 2011 ; Volume 110-116 , Oct , 2012 , Pages 4522-4526 ; 16609336 (ISSN) ; 9783037852620 (ISBN) Ebrahimi, M ; Niaki, S. A ; Salarieh, H ; Sharif University of Technology
    Abstract
    In airplanes, engine mounting structures have two primary performances: 1- They sustain all loads which engines produces or those which are exerted on engines in different maneuvering conditions. 2- They make the thrust load and the centric line of its containing cabin concentric [1]. In this paper, analysis of a mounting engine structure with the purpose of the accurate adjustment of the engine in its cabin is presented. Some sample diagrams, which introduced ideal adjustment angles for a specific aircraft, is proposed. These diagrams are obtained with the help of a MATLAB program that can be used for any dimension of the engine and cabin. Therefore, with the aid of these diagrams or this... 

    Computer simulation of turbocharged aftercooled gasoline engine

    , Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) Kharazmi, S ; Hajilouy Benisi, A ; Mozafari, A. A ; Sharif University of Technology
    American Society of Mechanical Engineers  2006
    Abstract
    Turbocharging of gasoline engines has been improved less than diesel engines due to some difficulties, especially knock phenomena. They require wider air flow range and faster response too. A computer code is developed to simulate turbocharged gasoline engine behavior. A three zone combustion model is employed. Different performance curves at speed and equivalence ratio ranges are prepared. By this code naturally aspirated and turbocharged behavior are compared. A turbocharged aftercooled engine has been studied in various cases to complete the investigation. Some aftercooler effects are described experimentally. Modeling and experimental results are compared providing valuable achievements.... 

    HSE management challenges in Iranian civil projects

    , Article Proceedings, Annual Conference - Canadian Society for Civil Engineering, 14 June 2011 through 17 June 2011 ; Volume 3 , 2011 , Pages 2268-2277 ; 9781618392183 (ISBN) Fallah, F ; Mortaheb, M. M ; Sharif University of Technology
    2011
    Abstract
    HSE management is one of the key topics in project management that plays a significant role in indication of success and soundness of projects. According to the official reports and statistics, construction industry has annually incurred a great deal of expenses and losses due to neglecting the role of HSE issues in the projects worldwide. Since many challenges and problems related to HSE faced Iranian civil engineers and construction managers, recently the HSE have been regarded as a highly critical issue in Iran. Observations show that many Iranian managers and engineers, in their daily activities, have the tendency to ignore the HSE related rules. The aim of this research is to evaluate... 

    An investigation on the effects of gas pressure drop in heat exchangers on dynamics of a free piston stirling engine

    , Article International Journal of Engineering, Transactions B: Applications ; Volume 30, Issue 2 , 2017 , Pages 1243-1252 ; 1728144X (ISSN) Zare, S ; Tavakolpour Saleh, A. R ; Aghajanzadeh, O ; Sharif University of Technology
    Materials and Energy Research Center  2017
    Abstract
    This paper is devoted to study the effects of pressure drop in heat exchangers on the dynamics of a free piston Stirling engine. First, the dynamic equations governing the pistons as well as the gas pressure equations for hot and cold spaces of the engine are extracted. Then, by substituting the obtained pressure equations into the dynamic relationships the final nonlinear dynamic equations governing the free piston Stirling engine are acquired. Next, effects of the gas pressure drop in heat exchangers on maximum strokes of the pistons and their velocities and accelerations are investigated. Furthermore, influences of pressure drop increase in the heat exchangers on maximum and minimum gas... 

    A News Semantic Search Engine Based On the Events

    , M.Sc. Thesis Sharif University of Technology Beheshti Foroutani, Homayoun (Author) ; Sadighi Moshkinani, Mohsen (Supervisor)
    Abstract
    The rapid growth of information on the web and the need for information sharing on one hand and also as news plays an important role in our life and internet becomes the biggest repository for keeping this news on the other hand, lead us to research in this domain.
    In this thesis, we introduce a new framework for searching news by considering the relation between news and events. This framework called NewsSe. NewsSe considers news as a series of events in order to cover all aspects of news. NewsSe uses Domain Ontology and Event Ontology to extract the concepts and relations existed in news. NewsSe consists of 4 different modules. NewsCr is a crawler which uses a new methodology for... 

    Modeling and estimation of unmeasured variables in a wastegate operated turbocharger

    , Article Journal of Engineering for Gas Turbines and Power ; Vol. 136, Issue. 5 , 2014 ; ISSN: 07424795 Salehi, R ; Vossoughi, G ; Alasty, A ; Sharif University of Technology
    Abstract
    Estimation of relevant turbocharger variables is crucial for proper operation and monitoring of turbocharged (TC) engines, which are important in improving fuel economy of vehicles. This paper presents mean-value models developed for estimating gas flow over the turbine and the wastegate (WG), the wastegate position, and the compressor speed in a TC gasoline engine. The turbine is modeled by an isentropic nozzle with a constant area and an effective pressure ratio calculated from the turbine upstream and downstream pressures. Another physically sensible model is developed for estimating either the WG flow or position. Provided the WG position is available, the WG flow is estimated using the... 

    Historiographical map of Iranian engineering scientific publications during 1939-2011

    , Article International Journal of Information Science and Management ; Volume 11, Issue 2 , 2013 , Pages 1-24 ; 20088302 (ISSN) Saghafi, S ; Asadi, M ; Osareh, F ; Sharif University of Technology
    2013
    Abstract
    Bibliometric, and scientometric approaches are used to provide appropriate tools for evaluating scientific products at local, national, and international levels. Iran, the same as other countries, has many universities and research centers in the field of engineering that Iran's most of the scientific products account for the field of engineering. This study is a descriptive approach using scientometric methods. is The present paper mainly focuses on visualizing the structure of the Iranian scientific publications in the field of engineering indexed in Thomson Reuters (ISI) accessible via WoS during 1939-2011. To draw the historiographical map of Iranian scientific outputs in the field of... 

    Recruitment processes in academia: does the emperor have any clothes?

    , Article Science and Engineering Ethics ; 2015 ; 13533452 (ISSN) Ataie Ashtiani, B ; Sharif University of Technology
    Kluwer Academic Publishers  2015
    Abstract
    The final outcome of promotion and recruitment processes in universities should be conventional and plausible by the members of the relevant scientific community, to affirm that the processes have been competitive and fair. The objective of this opinion letter is to make a plea for the importance of the post-auditing and quantitative assessment of the selection criteria. It is shown that for an example case the outcome of the post-audit does not look reasonable from an external point of view, at least regarding the research competency  

    Designing and implementing basic sciences ontology based on concepts and relationships of relevant thesauri

    , Article Iranian Journal of Information Processing Management ; Volume 30, Issue 3 , Nov , 2015 , Pages 677-696 ; 22518223 (ISSN) Hosseini Beheshti, M. S ; Ejei, F ; Sharif University of Technology
    Iranian Research Institute for Scientific Information and Documentation  2015
    Abstract
    Currently, the main portion of knowledge is stored in electronic texts and documents and for transferring that knowledge effectively, we must use proper methods to gather and retrieve relevant information. Ontologies provide means to produce structured documents and use intelligent search instead of keyword search. Ontology defines the common words and concepts used to describe and represent an area of knowledge. However, developing ontologies is a time consuming and labor work. So, many ontology developers try to facilitate and speed up this process by reusing other resources. In fact, thesaurus contains semantic information and hierarchical structure that make it an appropriate resource... 

    Energy and exergy analyses of a spark-ignition engine

    , Article International Journal of Exergy ; Volume 7, Issue 5 , 2010 , Pages 547-563 ; 17428297 (ISSN) Ameri, M ; Kiaahmadi, F ; Khanaki, M ; Nazoktabar, M ; Sharif University of Technology
    2010
    Abstract
    In this paper, the performance of an internal combustion engine is evaluated at the steady-state condition by application of energy and exergy analysis using the experimental test results. The energy and exergy balances are calculated at different engine speeds. The results show that the heat rejection of energy and exergy flow increases with increasing engine speed. The exergy efficiencies are slightly higher than the corresponding energy efficiencies. The results of this study have revealed that the most important source of the system inefficiency is the destruction of exergy by irreversible processes, mostly by the combustion. One can conclude that the use of a combined energy and exergy... 

    Skin diseases modeling using combined tissue engineering and microfluidic technologies

    , Article Advanced Healthcare Materials ; Volume 5, Issue 19 , 2016 , Pages 2459-2480 ; 21922640 (ISSN) Mohammadi, M. H ; Heidary Araghi, B ; Beydaghi, V ; Geraili, A ; Moradi, F ; Jafari, P ; Janmaleki, M ; Valente, K. P ; Akbari, M ; Sanati Nezhad, A ; Sharif University of Technology
    Wiley-VCH Verlag 
    Abstract
    In recent years, both tissue engineering and microfluidics have significantly contributed in engineering of in vitro skin substitutes to test the penetration of chemicals or to replace damaged skins. Organ-on-chip platforms have been recently inspired by the integration of microfluidics and biomaterials in order to develop physiologically relevant disease models. However, the application of organ-on-chip on the development of skin disease models is still limited and needs to be further developed. The impact of tissue engineering, biomaterials and microfluidic platforms on the development of skin grafts and biomimetic in vitro skin models is reviewed. The integration of tissue engineering and...