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    Building energy modeling with OpenStudio : a practical guide for students

    , Book Brackney, Larry ; Parker, Andrew ; Macumber, Daniel
    Springer International Publishing AG  2018

    The role of particle size on the laser sintering of iron powder

    , Article Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science ; Volume 35, Issue 5 , 2004 , Pages 937-948 ; 10735615 (ISSN) Simchi, A ; Sharif University of Technology
    Minerals, Metals and Materials Society  2004
    Abstract
    The effects of powder particle size on the densification and microstructure of iron powder in the direct laser sintering process were investigated. Iron powders with particle sizes ranging from 10 to 200 μm were used. It was found that the sintered density increases as the laser energy input is increased. There is, however, a saturation level at which higher density cannot be obtained even at very intensive energy input. This saturation density increases as the size of the iron particles decreases. Meanwhile fine powders with narrow particle size distributions have a tendency toward agglomeration, and coarse powders with broad particle size distributions have a tendency toward segregation,... 

    CAD-directed SEU susceptibility reduction in FPGA circuits designs

    , Article 2007 IEEE International Symposium on Circuits and Systems, ISCAS 2007, New Orleans, LA, 27 May 2007 through 30 May 2007 ; 2007 , Pages 3675-3678 ; 02714310 (ISSN) Zarand, H. R ; Miremadi, S. G ; Pradhan, D. K ; Mathew, J ; Sharif University of Technology
    2007
    Abstract
    This paper presents a SEU-mitigative placement and route of circuits in the FPGAs which is based on the popular placement and route tool The tool is modified so that during placement and routing, decisions are taken with awareness of SEU-mitigation and no redundancies during the placement and routing are used but the algorithms are based on the SEU avoidance. We have investigated the effect of this tool on several MCNC benchmarks and the results of the placement and routing have been compared to the traditional one. The evaluations of results show that placement and routing can decrease the SEU rate of circuits implemented on FPGAs about 22%. However, it increases critical path delay and... 

    Allocation and scheduling of digital dentistry services in a dental cloud manufacturing system

    , Article International Journal of Computer Integrated Manufacturing ; Volume 35, Issue 6 , 2022 , Pages 645-661 ; 0951192X (ISSN) Valizadeh, S ; Fatahi Valilai, O ; Houshmand, M ; Sharif University of Technology
    Taylor and Francis Ltd  2022
    Abstract
    Recent enhancements in computer aided design and manufacturing have made dentistry workflow more effective. Dental products are highly customized and personalized for patients. So, they require manufacturing processes for flexibility and agility and fulfilling requirements like quality, delivery time and cost. Various types of scanners, design software and production devices are used by stakeholders in digital dentistry. Also, other stakeholders such as dentists, dental surgeons and lab technicians work together to respond to patient demands to produce the required products while they are distributed in different geographical locations. This paper introduces a new practical and... 

    OD3P: On-demand page paired PCM

    , Article Proceedings - Design Automation Conference ; 2-5 June , 2014 , pp. 1-6 ; ISSN: 0738100X ; ISBN: 9781450327305 Asadinia, M ; Arjomand, M ; Sarbazi-Azad, H ; Sharif University of Technology
    Abstract
    With current memory scalability challenges, Phase Change Memory (PCM) is viewed as an attractive replacement to DRAM. The preliminary concern for PCM applicability is its limited write endurance that is highly affected by pro-cess variation in nanometer regime. This increases the vari- ation in cell lifetime resulting in early and sudden reduc- tion in main memory capacity due to wear-out of few cells. When some memory pages reach their endurance limits, other pages may be far from their limits even when using a perfect wear-leveling. Recent studies have proposed redi- rection or correction schemes to alleviate this problem, but all suffer from poor throughput or latency. On contrary, we... 

    OD3P: On-demand page paired PCM

    , Article Proceedings - Design Automation Conference ; 2014 Asadinia, M ; Arjomand, M ; Sarbazi-Azad, H ; Sharif University of Technology
    Abstract
    With current memory scalability challenges, Phase Change Memory (PCM) is viewed as an attractive replacement to DRAM. The preliminary concern for PCM applicability is its limited write endurance that is highly affected by pro-cess variation in nanometer regime. This increases the vari- ation in cell lifetime resulting in early and sudden reduc- tion in main memory capacity due to wear-out of few cells. When some memory pages reach their endurance limits, other pages may be far from their limits even when using a perfect wear-leveling. Recent studies have proposed redi- rection or correction schemes to alleviate this problem, but all suffer from poor throughput or latency. On contrary, we... 

    CLASS: Combined logic and architectural soft error sensitivity analysis

    , Article Proceedings of the Asia and South Pacific Design Automation Conference, ASP-DAC ; 2013 , Pages 601-607 ; 9781467330299 (ISBN) Ebrahimi, M ; Chen, L ; Asadi, H ; Tahoori, M. B ; Sharif University of Technology
    2013
    Abstract
    With continuous technology downscaling, the rate of radiation induced soft errors is rapidly increasing. Fast and accurate soft error vulnerability analysis in early design stages plays an important role in cost-effective reliability improvement. However, existing solutions are suitable for either regular (a.k.a address-based such as memory hierarchy) or irregular (random logic such as functional units and control logic) structures, failing to provide an accurate system-level analysis. In this paper, we propose a hybrid approach integrating architecture-level and logic-level techniques to accurately estimate the vulnerability of all regular and irregular structures within a microprocessor.... 

    Towards aging-induced approximations

    , Article Proceedings - Design Automation Conference, 18 June 2017 through 22 June 2017 ; Volume Part 128280 , 2017 ; 0738100X (ISSN) ; 9781450349277 (ISBN) Amrouch, H ; Khaleghi, B ; Gerstlauer, A ; Henkel, J ; Sharif University of Technology
    Abstract
    In recent technology nodes, wide guardbands are needed to overcome reliability degradations due to aging. Such guardbands manifest as reduced efficiency and performance. Existing approaches to reduce guardbands trade off aging impact for increased circuit overhead. By contrast, the goal of this work is to completely remove guardbands through exploring, for the first time, application of approximate computing principles in the context of aging. As a result of naively narrowing or removing guardbands, timing errors start to appear as transistors age. We demonstrate that even in circuits that may tolerate errors, aging can be catastrophic due to unacceptable quality loss. Furthermore,... 

    Effect of source phase difference on static transfer switch performance

    , Article IEEE Transactions on Power Delivery ; Volume 22, Issue 2 , 2007 , Pages 1125-1131 ; 08858977 (ISSN) Mokhtari, H ; Iravani, M. R ; Sharif University of Technology
    2007
    Abstract
    A thyristor-based static transfer switch (STS) provides a continuous supply for a voltage sensitive load through fast transfer between two sources when the main source does not meet load voltage requirements. This paper investigates the impact of phase difference between the corresponding voltages of the two sources on the load transfer performance achieved by an STS. The studies are performed on the IEEE benchmark STS-1 system using the power system computer-aided design/ electromagnetic transient dc simulation software. The studies indicate that the impact of phase difference on the STS load transfer time is insignificant when the sensitive load is a passive (e.g., RL) load. However, if... 

    On the hardware-software partitioning: The Classic General Model (CGM)

    , Article 2006 Canadian Conference on Electrical and Computer Engineering, CCECE'06, Ottawa, ON, 7 May 2006 through 10 May 2006 ; 2006 , Pages 1922-1925 ; 08407789 (ISSN); 1424400384 (ISBN); 9781424400386 (ISBN) JavanHemmat, H ; Goudarzi, M ; Hessabi, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2006
    Abstract
    In this paper we introduce a mathematical modeling tool (called Classic General Model: CGM) for the general problem of hardware-software codesign so that different partitioning algorithms can be easily and quickly developed and compared in this same framework. CGM introduces a simple but efficient model which supports single/multiprocessor, primal and dual approaches, fine or coarse granularity. CGM determines solutions by stating Mapping, Implementation and Permutation arrays. For judging among solutions of a certain algorithm, an Objective Function is defined. After modeling the problem by CGM we have a classic problem: finding the best values for elements of three arrays to optimize the... 

    Application of Knowledge-based Systems (kbs) in Exchange and Integration Manufacturing Systems Information with Cloud Manufacturing Approach (In Case Cooling Tower)

    , M.Sc. Thesis Sharif University of Technology Ghayazi, Abdolhossein (Author) ; Houshmand, Mahmoud (Supervisor)
    Abstract
    Product knowledge is the most precious asset of any manufacturing company, particularly for OKP companies. High level of customization is one characteristic of OKP which means more customer involvements in OKPPD activities, and customer requirements and expectations may be changing at any activity in PD, e.g., at designing stage. As SMEs, OKP companies always have limitation in resources such as machines tools, human resources, cutters, clamps, so managing the limitations is one of the major challenges that must be faced for maximizing the efficiently and productivity. The part of design that involves fuzzy problems and a lot of product knowledge, it is a critical part for the entire PD. In... 

    Integration of Design and Manufacturing Systems Using Neutral Data Structure

    , Ph.D. Dissertation Sharif University of Technology Mokhtar, Alireza (Author) ; Hooshmand, Mahmoud (Supervisor)
    Abstract
    In competitive environment of quick market changes, developing an interoperable manufacturing system is a necessity. Process planning as a connection link between design and manufacturing, has never been able to integrate these up/down stream activities and in spite of employing computer systems, CAPP’s information has been managed in an isolated manner. To realize interoperability, the exchange of part and product data must be independent of their platforms. There are two basic approaches for this purpose: i) Utilizing interface and ii) Utilizing neutral formats. STEP (Standard for the Exchange of Product data) plays a significant role as a neutral data model to integrate design,... 

    Breakup of microdroplets in asymmetric T junctions

    , Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 87, Issue 5 , 2013 ; 15393755 (ISSN) Samie, M ; Salari, A ; Shafii, M. B ; Sharif University of Technology
    2013
    Abstract
    Symmetric T junctions have been used widely in microfluidics to generate equal-sized microdroplets, which are applicable in drug delivery systems. A newly proposed method for generating unequal-sized microdroplets at a T junction is investigated theoretically and experimentally. Asymmetric T junctions with branches of identical lengths and different cross sections are utilized for this aim. An equation for the critical breakup of droplets at asymmetric T junctions and one for determining the breakup point of droplets are developed. A good agreement was observed between the theories (present and previous) and the experiments  

    Fully-Tunable microwave photonic filter with complex coefficients using tunable delay lines based on frequency-Time conversions

    , Article Optics Express ; Volume 20, Issue 20 , 2012 , Pages 22728-22734 ; 10944087 (ISSN) Mokhtari, A ; Preuler, S ; Jamshidi, K ; Akbari, M ; Schneider, T ; Sharif University of Technology
    Abstract
    A fully electrically tunable microwave photonic filter is realized by the implementation of delay lines based on frequency-Time conversion. The frequency response and free spectral range (FSR) of the filter can be engineered by a simple electrical tuning of the delay lines. The method has the capability of being integrated on a silicon photonic platform. In the experiment, a 2-Tap tunable microwave photonic filter with a 3-dB bandwidth of 2.55 GHz, a FSR of 4.016 GHz, a FSR maximum tuning range from -354 MHz to 354 MHz and a full FSR translation range is achieved  

    Modeling of interaction between a three-fingered surgical grasper and human spleen

    , Article Studies in Health Technology and Informatics, 9 February 2011 through 12 February 2011, Newport Beach, CA ; Volume 163 , 2011 , Pages 663-669 ; 09269630 (ISSN) ; 9781607507055 (ISBN) Tirehdast, M ; Mirbagheri, A ; Asghari, M ; Farahmand, F ; Sharif University of Technology
    2011
    Abstract
    The aim of this study was to develop a more sophisticated model of the spleen tissue and investigate its interactions with a three-fingered laparoscopic grasper. The spleen tissue, modeled as a hyper viscoelastic material, was subjected to external loadings, imposed by rigid grasping jaws. The tissue deformation as well as the sliding occurrence between tissue and jaws was investigated using nonlinear finite element method. Results indicated that a grasping configuration which aimed a sufficiently large piece of spleen with small radius of curvature was more successful for effective grasping. The trends and magnitudes of the tooltissue interaction forces obtained during effective and... 

    An analytical model for cutter-workpiece engagement calculation in ball-end finish milling of doubly curved surfaces

    , Article International Journal of Advanced Manufacturing Technology ; Volume 102, Issue 5-8 , 2019 , Pages 1635-1657 ; 02683768 (ISSN) Ghorbani, M ; Movahhedy, M. R ; Sharif University of Technology
    Springer London  2019
    Abstract
    This paper presents a new analytical model for calculating the cutter-workpiece engagement (CWE) boundaries in the ball-end finish milling process of curved surfaces. To this end, first, a quadratic mathematical representation considering the principal curvatures of the surface is employed to locally describe the workpiece surface around the instantaneous cutting region. This description, then, is utilized to find the intersection curves of the tool rotary and workpiece surfaces in three ball-end milling modes including slotting, first cutting, and following cutting. Through comparison studies, the model predictions are verified by the corresponding results obtained via solid modeling in... 

    An autonomous framework for interpretation of 3D objects geometric data using 2D images for application in additive manufacturing

    , Article PeerJ Computer Science ; Volume 7 , 2021 , Pages 1-32 ; 23765992 (ISSN) Rezaei, M. R ; Houshmand, M ; Valilai, O. F ; Sharif University of Technology
    PeerJ Inc  2021
    Abstract
    Additive manufacturing, artificial intelligence and cloud manufacturing are three pillars of the emerging digitized industrial revolution, considered in industry 4.0. The literature shows that in industry 4.0, intelligent cloud based additive manufacturing plays a crucial role. Considering this, few studies have accomplished an integration of the intelligent additive manufacturing and the service oriented manufacturing paradigms. This is due to the lack of prerequisite frameworks to enable this integration. These frameworks should create an autonomous platform for cloud based service composition for additive manufacturing based on customer demands. One of the most important requirements of... 

    , M.Sc. Thesis Sharif University of Technology Fatahi Valilaei, Omid (Author) ; Hoshmand, Mahmoud (Supervisor)
    Abstract
    Integrated design includes CAD, process planning and CNC code generation based on an integrated data structure. To enable different CAD/CAM software solutions to be interoperable, it is required to support data exchange in manufacturing enterprises. To realize interoperability there are two basic approaches: i. to focus on STEP standard to support data exchange between CAD systems as well as CAPP/CAM and CNC machining systems; the use of STEP standard ensures the data integration based on STEP standard. ii. utilizing a platform consists of structures and procedures to enable exchange of data between different CAD/CAM/CAPP software applications seamlessly. In this article, the important... 

    Content Based Mammogram Image Retrieval Based on the Multiclass Visual Problem

    , M.Sc. Thesis Sharif University of Technology Siyahjani, Farzad (Author) ; Fatemizadeh, Emad (Supervisor)
    Abstract
    In recent years there has been a great effort to enhance the computer-aided diagnosis systems, Since expertise elicited from past resolved cases plays an important role in medical applications, and images acquired from various cases have a great contribution to diagnosis of the abnormalities, Content based medical image retrieval has become an active research area for many scientists. In this project we proposed a new framework to retrieve visually similar images from a large database, in which visual similarity is regarded as much as the semantic category relevance, we used optimized wavelet transform as the multi-resolution analysis of the images and extracted various statistical SGLDM... 

    A Path Planning Method Based on Basic RRT* Algorithm and Cagd-Based Curves Ffor Non-Holonomic Wheeled Mobile Robots

    , M.Sc. Thesis Sharif University of Technology Eshtehardian, Ali (Author) ; Khodaygan, Saeed (Supervisor)
    Abstract
    Throughout recent decades, one of the most important and challenging problems in robotics has been robot's path planning. Path planning means a robot must find its way from start to the goal point and track it without any collision to the obstacles. For this aim during the recent decades a wide variety of algorithms such as A*, Dijkstra and … have been proposed that some of which generate an optimal path as their output while others tend to create only a path regardless of its optimality. One of the most practical path planning methods is RRT algorithm which is executable in real-world applications, and by generating some nodes randomly then creating a tree-based graph, thereby outputting a...