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process-engineering
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Definition of a Set of Process Patterns and a Generic Meta-Model for Component-Based Development Methodologies
, M.Sc. Thesis Sharif University of Technology ; Ramsin, Raman (Supervisor)
Abstract
Although Component-Based Development (CBD) is not a novel approach, it is still extensively used for building various types of software systems, and is expected to remain popular for the foreseeable future. There exist several software development methodologies that support the construction of component-based systems, and the domain has matured over the years. When viewed collectively, CBD methodologies have indeed addressed all the relevant issues; however, none of the methodologies covers all the aspects of component-based software development. A general methodology can resolve this through addressing the deficiencies while being customizable according to the specifics of the project...
Design and Optimization of Helium Recovery Process from Natural Gas
, M.Sc. Thesis Sharif University of Technology ; Afshin, Hossein (Supervisor) ; Farhanieh, Bijan (Co-Supervisor)
Abstract
Helium is a valuable substance that is widely used in industry and medicine because of its unique properties. Due to the increasing demand for helium in the global market, several helium extraction units have been launched in the world in recent years; Nevertheless, there is still a significant gap between projected global helium production capacity and demand. Today, natural gas is known as the main source of helium on the earth. The method of industrial extraction of helium from natural gas is cryogenic. Due to the low temperature of this process, relatively high power consumption is used to extract helium from natural gas. Therefore, the optimization of this process is of great...
Design and Optimization of Helium Extraction and Liquefaction Cycle from Natural Gas by Direct Method
, Ph.D. Dissertation Sharif University of Technology ; Afshin, Hossein (Supervisor)
Abstract
Helium is known as a strategic material due to its unique properties and applications in the development of advanced industries. Currently, natural gas is the only source from which helium can be produced economically. The United States, Qatar, Algeria, and Russia have the largest share of helium production, respectively. In this research, the process of helium extraction from natural gas and its liquefaction, independent of LNG production based on helium in South Pars gas of Iran, which is the largest helium reservoir in the world, were designed and simulated.In the helium liquefaction section, the speed and accuracy of the process simulation were improved by developing a home code based on...
INFELT STEP: An integrated and interoperable platform for collaborative CAD/CAPP/CAM/CNC machining systems based on STEP standard
, Article International Journal of Computer Integrated Manufacturing ; Volume 23, Issue 12 , 2010 , Pages 1095-1117 ; 0951192X (ISSN) ; Houshmand, M ; Sharif University of Technology
Abstract
Integrated product development is comprised of CAD, process planning and CNC code generation based on an integrated data structure. To make various CAD/CAM software solutions with different internal product data structures interoperable, it is necessary to realise reliable and robust information exchange capability in a manufacturing environment. To enable interoperability amongst integrated product development processes, management of collaboration of diverse CAD/CAM software packages is of outmost importance. In this article, the fundamental requirements for achieving interoperability and collaboration management in an integrated, enterprise-wide, product development process environment...
Optimal riser design in sand casting process by topology optimization with SIMP method I: poisson approximation of nonlinear heat transfer equation
, Article Structural and Multidisciplinary Optimization ; Volume 36, Issue 2 , 25 January , 2008 , Pages 193-202 ; 1615147X (ISSN) ; Davami, P ; Sharif University of Technology
2008
Abstract
The optimal design of a casting feeding system is considered. The problem is formulated as the volume constrained topology optimization and is solved with the finite element analysis, explicit design sensitivity, and numerical optimization. In contrast to the traditional topology optimization where the objective function is defined on the design space, in the presented method, the design space is a subset of the complement of the objective function space. To accelerate optimization procedure, the nonlinear unsteady heat transfer equation is approximated with a Poisson-like equation. The feasibility of the presented method is supported with illustrative examples. © 2007 Springer-Verlag
Unsteady three dimensional aerodynamic load prediction using neural networks
, Article 2007 International Joint Conference on Neural Networks, IJCNN 2007, Orlando, FL, 12 August 2007 through 17 August 2007 ; 2007 , Pages 1995-1999 ; 10987576 (ISSN) ; 142441380X (ISBN); 9781424413805 (ISBN) ; Ghorbanian, K ; Gholamrezaei, M ; Amiralaei, M. R ; Sharif University of Technology
2007
Abstract
The focus of the current research is to develop an intelligent design process that uses existing data as a tool for the designers, one that fully utilizes the ability of the computer to interpolate and extrapolate the scattered data. Surface pressure measurements were conducted for a pitch oscillation wing in a subsonic closed circuit wind tunnel. Experimental results have been used to train a multilayer perceptron network. This work indicates that neural networks can reliably predict aerodynamic coefficients and forecast the effects of reduced frequencies on the wind turbine blade performance. ©2007 IEEE
Electricity generation scheduling with large-scale wind farms using particle swarm optimization
, Article Electric Power Systems Research ; Volume 79, Issue 5 , 2009 , Pages 826-836 ; 03787796 (ISSN) ; Vakilian, M ; Sharif University of Technology
2009
Abstract
Large-scale integration of wind power in the electricity system presents some planning and operational difficulties, which are mainly due to the intermittent and difficult nature of wind prediction process. Therefore it is considered as an unreliable energy source. This paper presents a new approach for solving the generation scheduling (GS) problem. It will consider the reserve requirement, load balance and wind power availability constraints. The particle swarm optimization (PSO) method is suggested to deal with the equality and inequality constraints in the GS problem. The proposed PSO is applied to a 12-unit test system (including 10 conventional thermal generating units and 2 wind...
Towards tool support for situational engineering of agile methodologies
, Article Proceedings - Asia-Pacific Software Engineering Conference, APSEC, 30 November 2010 through 3 December 2010, Sydney, NSW ; 2010 , Pages 326-335 ; 15301362 (ISSN) ; 9780769542669 (ISBN) ; Hasani Sadi, M ; Ramsin, R ; Sharif University of Technology
2010
Abstract
Various agile software development methodologies, practices, and techniques have been proposed in the last decade; some present novel ideas, while many are simply made up of tasks and techniques borrowed from prominent agile methodologies. Each of these methodologies prescribes a set of practices and techniques which are deemed appropriate for application in a specific context. However, there exists no single method which fits all project situations. This has resulted in the advent of Situational Method Engineering (SME) approaches, which are used for developing software methodologies that are tailored to fit the specific circumstances of the project situation at hand. Since tool support has...
Application of fuzzy theory for traffic assignment
, Article 18th IASTED International Conference on Modelling and Simulation, MS 2007, Montreal, QC, 30 May 2007 through 1 June 2007 ; 2007 , Pages 604-608 ; 10218181 (ISSN); 9780889866638 (ISBN) ; Ramezani, H ; Sharif University of Technology
2007
Abstract
Traffic assignment is one of the primary steps in the urban transportation planning process. There are several parameters that affect on drivers route choice. These factors arenot shown completely in the classic traffic assignment techniques so, these methodes donot have acceptable accuracy in the link volume estimating. Therefore many researchers have been tried to use fuzzy set theory in order to gain more precise approximation in traffic assignment. In this paper, we intend to propose a new fuzzy assignment model which has more flexibility relarive to driver behavior characteristics. At first, our assumptions are cited and then we illustrate how the membership function of the travel time...
Computer intrusion detection using an iterative fuzzy rule learning approach
, Article 2007 IEEE International Conference on Fuzzy Systems, FUZZY, London, 23 July 2007 through 26 July 2007 ; 2007 ; 10987584 (ISSN) ; 1424412102 (ISBN); 9781424412105 (ISBN) ; Habibi, J ; Sharif University of Technology
2007
Abstract
The process of monitoring the events occurring in a computer system or network and analyzing them for sign of intrusions is known as intrusion detection system (IDS). The objective of this paper is to extract fuzzy classification rules for intrusion detection in computer networks. The proposed method is based on the iterative rule learning approach (IRL) to fuzzy rule base system design. The fuzzy rule base is generated in an incremental fashion, in that the evolutionary algorithm optimizes one fuzzy classifier rule at a time. The performance of final fuzzy classification system has been investigated using intrusion detection problem as a high-dimensional classification problem. Results show...
An efficient multi-band spectral subtraction method for robust speech recognition
, Article 2007 9th International Symposium on Signal Processing and its Applications, ISSPA 2007, Sharjah, 12 February 2007 through 15 February 2007 ; 2007 ; 1424407796 (ISBN); 9781424407798 (ISBN) ; Sameti, H ; Babaali, B ; Manzuri Shalmani, M. T ; Sharif University of Technology
2007
Abstract
In this paper we present a novel approach for adjusting a multi band spectral subtraction filter coefficients based on speech recognition system results. Currently most speech enhancement techniques are designed according to various waveform level criteria such as maximizing SNR or minimizing signal error. However improvement in these criteria does not necessarily result in increasing speech recognition performance. Only if these methods generate sequence of features that maximize or increase the likelihood of the correct transcription relative to other incorrect competing hypotheses, speech recognition performance will increase. Here we use an utterance with a known transcription and...
Study the failure of casted copper anode: The formation of bumps defects on the surface of the anode during casting
, Article Engineering Failure Analysis ; Volume 138 , 2022 ; 13506307 (ISSN) ; Reza Khayati, G ; Javad Khorasani, S. M ; Assadat Yaghubi, N ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Copper anode (∼98%) is widely used to produce the cathode (99.995 wt%) in electrorefining process. These anodes sometimes become problematic from the production line due to the presence of bumps/holes on their surface. To find the reason of this defect, chemical composition of the three casted anodes was determined by the quantmeter analysis. Also, the microscopic and phase analysis were done by FESEM, EDS, XRD, and XRF for three types of anodes bump. The chemical analysis of anodes confirmed a high level of sulfur and oxygen, which have a key role in the formation of bumps. The results confirmed the presence of impurities including Cu2S, BaSO4, CaCO3 and MgCO3, which cause the formation of...
Time decomposition in batch process integration
, Article Chemical Engineering and Processing: Process Intensification ; Volume 45, Issue 1 , 2006 , Pages 14-21 ; 02552701 (ISSN) ; Amidpour, M ; Rashtchian, D ; Sharif University of Technology
2006
Abstract
In this work, the concept of problem table decomposition for the thermal integration of continuous processes is extended to batch processes. The approach is based on a combination of time intervals using pinch analysis tools and energy storage system design. Pinch analysis improves energy efficiency for batch processes and it may increase the productivity of a revised plant. Operational and economical constraints may cause some limitation; therefore, in this approach process constraints and flexibilities are carefully considered by defining individual time and heat intervals. The approach is demonstrated on a case study. © 2005 Elsevier B.V. All rights reserved
Computer-aided method engineering: An analysis of existing environments
, Article 20th International Conference on Advanced Information Systems Engineering, CAiSE 2008, Montpellier, 16 June 2008 through 20 June 2008 ; Volume 5074 LNCS , 2008 , Pages 525-540 ; 03029743 (ISSN) ; 3540695338 (ISBN) ; Ramsin, R ; Sharif University of Technology
2008
Abstract
Analogous to Computer-Aided Software Engineering (CASE), which aims to facilitate Software Engineering through specialized tools, Computer-Aided Method Engineering (CAME) strives to support a wide range of activities carried out by method engineers. Although there is consensus on the importance of tool support in method engineering, existing CAME environments are incomplete prototypes, each covering just a few steps of the method engineering process. This paper summarizes the history and the state of the practice in CAME technology, and provides criteria-based critique on existing CAME environments, thus highlighting their strengths and weaknesses. © 2008 Springer-Verlag Berlin Heidelberg
Tuneable vibration absorber design to suppress vibrations: An application in boring manufacturing process
, Article Journal of Sound and Vibration ; Volume 318, Issue 1-2 , 2008 , Pages 93-108 ; 0022460X (ISSN) ; Bakhtiari Nejad, F ; Movahhedy, M. R ; Sharif University of Technology
2008
Abstract
Dynamic vibration absorbers are used to reduce the undesirable vibrations in many applications such as electrical transmission lines, helicopters, gas turbines, engines, bridges, etc. Tuneable vibration absorbers (TVA) are also used as semi-active controllers. In this paper, the application of a TVA for suppression of chatter vibrations in the boring manufacturing process is presented. The boring bar is modeled as a cantilever Euler-Bernoulli beam and the TVA is composed of mass, spring and dashpot elements. In addition, the effect of spring mass is considered in this analysis. After formulation of the problem, the optimum specifications of the absorber such as spring stiffness, absorber...
Dealing with feature interactions for prismatic parts in STEP-NC
, Article Journal of Intelligent Manufacturing ; Volume 20, Issue 4 , 2009 , Pages 431-445 ; 09565515 (ISSN) ; Xu, X ; Lazcanotegui, I ; Sharif University of Technology
2009
Abstract
Determining the precedence of machining features is a critical issue in feature-based process planning. It becomes more complex when geometric interaction occurs between machining features. STEP-NC, the extension of STEP (ISO 10303) standard developed for CNC controllers, is a feature-based data model. It represents all the geometric and topological product data minus feature interactions. In this paper, machining precedence of interactive and non-interactive STEP-NC features is discussed. Local and global precedence of machining features are defined on the basis of geometric constraints, such as geometric interaction of features and feature approach face and technological constraint such as...
Virtual point-to-point links in packet-switched NoCs
, Article IEEE Computer Society Annual Symposium on VLSI: Trends in VLSI Technology and Design, ISVLSI 2008, Montpellier, 7 April 2008 through 9 April 2008 ; 2008 , Pages 433-436 ; 9780769531700 (ISBN) ; Sarbazi Azad, H ; Tavakkol, A ; Sharif University of Technology
2008
Abstract
A method to setup virtual point-to-point links between the cores of a packet-switched network-on-chip is presented in this paper which aims at reducing the NoC power consumption and delay. The router architecture proposed in this paper provides packet-switching, as well as a number of virtual point-to-point, or VIP (VIrtual Point-to-point) for short, connections. This is achieved by designating one virtual channel at each physical channel of a router to bypass the router pipeline. The mapping and routing algorithm exploits these virtual channels and tries to virtually connect the source and destination nodes of high-volume communication flows during task-graph mapping and route selection...
A fuzzy model for solving architecture styles selection multi-criteria problem
, Article EMS 2008, European Modelling Symposium, 2nd UKSim European Symposium on Computer Modelling and Simulation, Liverpool, 8 September 2008 through 10 September 2008 ; 2008 , Pages 388-393 ; 9780769533254 (ISBN) ; Ahmadi, H ; Habibi, J ; Kamandi, A ; Sharif University of Technology
2008
Abstract
The continuing process of software systems enlargement in size and complexity becomes system design extremely important for software production. In this way, the role of software architecture is significantly important in software development. It serves as an evaluation and implementation plan for software development and software evaluation. Consequently, choosing the correct architecture is a critical issue in software engineering domain. Moreover, software architecture selection is a multicriteria decision-making problem in which different goals and objectives must be taken into consideration. In this paper, more precise and suitable decisions in selection of architecture styles have been...
Intelligent flight-data-recorders; a step toward a new generation of learning aircraft
, Article 8th International Conference on Control, Decision and Information Technologies, CoDIT 2022, 17 May 2022 through 20 May 2022 ; 2022 , Pages 1545-1549 ; 9781665496070 (ISBN) ; Alipour, E ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
To understand how aerial accidents occur, the installation of flight data recorders (FDR) and cockpit voice recorders (CVR) have become mandatory by law. However, such devices play a passive role and are used once an accident has occurred. Recent advances in machine learning techniques and their application in solving engineering problems are the keys to creating a more active role for both FDR as well as CVR. Here, we investigate a new approach to bringing intelligence to an FDR (called I-FDR). Through a continuous data-mining process, an I-FDR could bring better situational awareness to the flight crew. An I-FDR, similar to the FDR, records all pertinent flying parameters. In addition,...
Generation expansion planning of stand-alone micro-power systems using MADM techniques
, Article 42nd International Universities Power Engineering Conference, UPEC 2007, Brighton, 4 September 2007 through 6 September 2007 ; 2007 , Pages 68-72 ; 1905593368 (ISBN); 9781905593361 (ISBN) ; Afsharnia, S ; Ehsan, M ; Kamalinia, S ; Sedighizadeh, M ; Sharif University of Technology
2007
Abstract
In this paper, Analytic Hierarchy Process and Data Envelopment Analysis are introduced as multi attribute decision making techniques in planning of standalone micro-power systems. The objective of the planning framework is to select the best configuration and capacity of different generating technologies in micro-power systems to minimize certain economical and environmental attributes. The economical attributes are capital cost and net present cost and the environmental attribute is emission. The proposed framework is illustrated by a case study on a real network in northern region of Iran