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    Implementation of green management concepts in sport complexes

    , Article International Journal of Environmental Science and Technology ; Volume 3, Issue 3 , 2006 , Pages 213-219 ; 17351472 (ISSN) Abbaspour, M ; Karbassi, A. R ; Khadivi, S ; Sharif University of Technology
    CEERS  2006
    Abstract
    Implementation of green management in sport complexes can ensure the continuous arrangement and assessment of activities from the environmental perspective and will end up in control and prevention of contaminants. Enghelab sport complex (ESC) in Iran is selected for this study due to its size and long-term activities. Due to the comprehensive plan of the aforesaid sports complex, numerous centers and departments were established in this site in order to materialize its envisioned sports, recreational and cultural objectives. The results of the questionnaires distributed amongst the members and the personnel of the complex revealed that approximately 50 % occupants were not acquainted with... 

    Minimization of adverse environmental effects of a sports complex through implementation of green management

    , Article 4th International Conference on Urban Regeneration and Sustainability, SUSTAINABLE CITY 2006, SC06, Tallin, 17 July 2006 through 19 July 2006 ; Volume 93 , 2006 , Pages 457-465 ; 17433541 (ISSN); 1845640403 (ISBN); 9781845640408 (ISBN) Abbaspour, M ; Karbasi, A. R ; Khadivi, S ; Sharif University of Technology
    WITPress  2006
    Abstract
    Implementation of green management in sports complexes can ensure the continuous arrangement and assessment of activities from an environmental perspective and will end up with the control and prevention of contaminants. Enghelab Sports Complex in Iran was selected for this study due to its size and long-term activities. The establishment of Enghelab Sports Complex is among important national projects whose framework was founded in the late 1950s. Due to the comprehensive plan of the aforesaid sports complex, numerous centers and departments were established in this site in order to materialize its envisioned sports, recreational and cultural objectives. Green management pursues greater... 

    Numerical solution of the nonlinear diffusivity equation in heterogeneous reservoirs with wellbore phase redistribution

    , Article Journal of Petroleum Science and Engineering ; Vol. 114 , 2014 , pp. 82-90 ; ISSN: 09204105 Khadivi, K ; Soltanieh, M ; Sharif University of Technology
    2014
    Abstract
    We consider the application of the Finite Element Method (FEM) for numerical pressure transient analysis under conditions where no reliable analytical solution is available. Pressure transient analysis is normally based on various analytical solutions of the linear one-dimensional diffusion equation under restrictive assumptions about the formation and its boundaries. For example, the formation is either assumed isotropic or a restrictive a priori assumption is made about its heterogeneity. The wellbore storage effect is also often considered without regard to the possibility of phase redistribution. In many practical situations such restrictions are not justified and analytical solutions do... 

    Cost-benefit analysis of energy saving strategies adopted by the commercial sector in Tehran

    , Article Environmental Progress and Sustainable Energy ; Volume 34, Issue 3 , 2015 , Pages 850-857 ; 19447442 (ISSN) Khadivi, S ; Moradi, M. A ; Sharif University of Technology
    John Wiley and Sons Inc  2015
    Abstract
    This study presents a cost-benefit analysis of energy saving strategies for the commercial sector inTehran City. The article includes a discussion of the estimated energy demand for various energy saving scenarios. The cost-benefit analysis was performed separately for seven energy-saving scenarios based on the energy demand and supply forecasting model. According to which, energy demand of the commercial sector was considered as final consumption, which is a function of different parameters such as number of commercial units, number of electric vehicles, volume of commercial activities, labor force, etc. The research findings indicated that all of the proposed scenarios are economically... 

    A coupled wellbore-reservoir flowmodel for numerical pressure transient analysis in vertically heterogeneous reservoirs

    , Article Journal of Porous Media ; Volume 16, Issue 5 , 2013 , Pages 395-400 ; 1091028X (ISSN) Khadivi, K ; Soltanieh, M ; Farhadpour, F. A ; Sharif University of Technology
    2013
    Abstract
    Pressure transient analysis in vertically heterogeneous reservoirs is examined. The inclusion of a separate model for the free fluid flow in the wellbore is essential to allow for hydraulic communication and mixing of the fluid issuing from different reservoir layers. A two-dimensional model coupling Darcy flow in the reservoir with Navier-Stokes flow in the wellbore is developed and solved by the finite element technique. The coupled wellbore-reservoir flow model is used to analyze a layered reservoir with an abrupt change in permeability and a thick formation showing a gradual change in permeability with depth. Contrary to conventional reservoir models, this new model is able to capture... 

    Energy demand model of the household sector and its application in developing metropolitan cities (case study: Tehran)

    , Article Polish Journal of Environmental Studies ; Volume 22, Issue 2 , February , 2013 , Pages 319-329 ; 12301485 (ISSN) Abbaspour, M ; Karbassi, A ; Asadi, M. K ; Moharamnejad, N ; Khadivi, S ; Moradi, M. A ; Sharif University of Technology
    2013
    Abstract
    Excessive energy consumption is one of the serious problems of large cities in Iran. In order to avoid unreasonable growth in energy use as well as conservation of natural resources, more attention should be paid to energy consumption patterns in metropolitan cities. Accordingly, the current study aims at analyzing energy demand and its related pollutants in the household sector in Tehran Metropolitan. The study includes a discussion of past trends and future scenarios to reduce greenhouse gas emissions in this sector. Using LEAP software and according to Iran's long-term development policies, energy demand and its greenhouse gas emissions were evaluated based on a baseline scenario within a... 

    Multi-Resolution Denoising of Well Test Data

    , Ph.D. Dissertation Sharif University of Technology Khadivi, Kourosh (Author) ; Soltanieh, Mohammad (Supervisor) ; Farhadpour, Farhad Ali (Co-Advisor)
    Abstract
    Permanent Downhole Gauge (PDG) has been employed since 1990s to acquire more information and better access to well and control production. PDG provides huge amount of pressure transient data during well test operation and production. However, such data are encountering with various noise and outliers. The noise and outliers can cause misleading and misinterpretation results. Therefore, denoising and outlier removal are two imperative steps before pressure transient analysis. The conventional denoising methods are mostly based on wavelet thresholding methods that preserve mean of data and have good performance when noise distribution is Gaussian distribution. However, noise distribution... 

    The relationship between an EFL teacher's gender and students' willingness to communicate

    , Article International Journal of Communication and Linguistic Studies ; Volume 10, Issue 4 , 2013 , Pages 17-29 ; 23277882 (ISSN) Khosravizadeh, P ; Pakzadian, S. S
    Common Ground Publishing  2013
    Abstract
    Learning a foreign language encompasses a process of trial and error that can lead to the progression of the learner's interlanguage, meaning that the learners make use of their language knowledge that receives feedback and brings about progress through diagnosis of the problems and being corrected by the teacher. Therefore, there exists a need to analyze the underlying reasons causing the students to remain taciturn with a low willingness to communicate (WTC) during a language class. There has been much work done investigating the role of the learner's stable personal characteristics (traits) along with their situational changes at a specific time (states) that influence the student's... 

    Design and development of a miniaturized roto-translational motion platform for microaerial vehicle identification

    , Article IEEE Aerospace and Electronic Systems Magazine ; Volume 39, Issue 12 , 2024 , Pages 24-35 ; 08858985 (ISSN) Abdollahi, M. R ; Pourtakdoust, S. H ; Mousavi, S. M. S
    IEEE  2024
    Abstract
    Accurate system identification (SI) is essential for flight controller design of unmanned aerial vehicles and microaerial vehicles (MAVs). SI can be performed either in frequency or time domain using flight test data. As flight testing is often costly and may even lead to catastrophic events before some flight stability analysis is at hand, a low-cost 5 degree-of-freedom free motion platform (FMP) is designed and used for initial identification of MAVs via wind tunnel testing. A typical MAV is constructed as a test case and equipped with inertial sensors for testing and validation purposes. The proposed FMP allows for both rotational as well as translational motions that in turn provide for... 

    An automated simple algorithm for realistic pore network extraction from micro-tomography images

    , Article Journal of Petroleum Science and Engineering ; Vol. 123, issue , 2014 , pp. 164-171 ; ISSN: 09204105 Rabbani, A ; Jamshidi, S ; Salehi, S
    2014
    Abstract
    Using 3-D scanned data to analyze and extract pore network plays a vital role in investigation of porous media's characteristics. In this paper, a new simple method is developed to detect pores and throats for analyzing the connectivity and permeability of the network. This automated method utilizes some of the common and well-known image processing functions which are widely accessible by researchers and this has led to an easy algorithm implementation. In this method, after polishing and quality control of images, using city-block distance function and watershed segmentation algorithm, pores and throats are detected and 3-D network is produced. This method can also be applied on 2-D images... 

    Discrimination of heart arrhythmias using novel features in heart rate phase space

    , Article Computing in Cardiology ; Volume 40 , Sept , 2013 , Pages 1035-1038 ; 23258861 (ISSN); 9781479908844 (ISBN) Moharreri, S ; Rezaei, S ; Salavatian, S
    2013
    Abstract
    In this paper, we try to recognize and distinguish different groups of arrhythmia using novel features which have been obtained from the heart rate's phase space in recent years. For this purpose, we used Triangular Phase Space Mapping (TPSM) and Parabolic Phase Space Mapping (PPSM). For recognition, we used three groups of 15 subjects using the Physionet database (Arrhythmia, Congestive Heart Failure (CHF), and Atrial Fibrillation (AF)) with Normal Sinus Rhythm (NSR). The obtained features discriminate arrhythmia from NSR by p

    An intelligent hybrid classification algorithm integrating fuzzy rule-based extraction and harmony search optimization: Medical diagnosis applications

    , Article Knowledge-Based Systems ; Volume 220 , 2021 ; 09507051 (ISSN) Mousavi, S. M ; Abdullah, S ; Akhavan Niaki, S. T ; Banihashemi, S ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Uncertainty is a critical factor in medical datasets needed to be overcome for increasing diagnosis efficiency. This paper proposes an intelligent classification algorithm comprising a fuzzy rule-based approach, a harmony search (HS) algorithm, and a heuristic algorithm to classify medical datasets intelligently. Two fuzzy approaches, as well as orthogonal and triangular fuzzy sets, are first utilized to define the attributes of data. Then, an HS algorithm is integrated with a heuristic to generate fuzzy rules to select the best rules in the fuzzy rule-based systems. Moreover, to improve the performance of the proposed classification approach, a three-phase parameter tuning approach is... 

    Performance evaluation of shared hosting security methods

    , Article Proc. of the 11th IEEE Int. Conference on Trust, Security and Privacy in Computing and Communications, TrustCom-2012 - 11th IEEE Int. Conference on Ubiquitous Computing and Communications ; 2012 , Pages 1310-1315 ; 9780769547459 (ISBN) Mirheidari, S. A ; Arshad, S ; Khoshkdahan, S ; Sharif University of Technology
    2012
    Abstract
    Shared hosting is a kind of web hosting in which multiple websites reside on one webserver. It is cost-effective and makes the administration easier for websites' owners. However, shared hosting has some performance and security issues. In default shared hosting configuration, all websites' scripts are executed under the webserver's user account regardless of their owners. Therefore, a website is able to access other websites' resources. This security problem arises from lack of proper isolation between different websites hosted on the same webserver. In this survey, we have examined different methods for handling mentioned security issue. Also we evaluated the performance of mentioned... 

    The behaviour of an artificially cemented sandy gravel

    , Article Geotechnical and Geological Engineering ; Volume 23, Issue 5 , 2005 , Pages 537-560 ; 09603182 (ISSN) Haeri, S. M ; Hosseini, S. M ; Toll, D. G ; Yasrebi, S. S ; Sharif University of Technology
    2005
    Abstract
    The major section of the city of Tehran, Iran has been developed on cemented coarse-grained alluvium. This deposit consists of gravely sand to sandy gravel with some cobbles and is dominantly cemented by carbonaceous materials. In order to understand the mechanical behaviour of this soil, a series of undrained triaxial compression tests and unconfined compression tests were performed on uncemented and artificially cemented samples. Portland cement type I was used as the cementation agent for preparing artificially cemented samples. Uncemented samples and lightly cemented samples (1.5% cement) tested at high confining pressure showed contractive behaviour accompanied with positive excess pore... 

    An imperialist competitive algorithm approach for multi-objective optimization of direct coupling photovoltaic-electrolyzer systems

    , Article International Journal of Hydrogen Energy ; Vol. 39, Issue 33 , 11 November , 2014 , pp. 18743-18757 ; ISSN: 03603199 Maroufmashat, A ; Sayedin, F ; Khavas, S. S
    2014
    Abstract
    In the context of sustainable clean hydrogen production pathways, photovoltaic-electrolyzer systems are one of the most promising alternatives for acquiring hydrogen from renewable energy sources. In fact, determining the optimal set of design and operating variables are always a key issue while coupling directly renewable electricity sources to PEM electrolyzers. Few previous studies have attempted to find the optimal size and operational condition of directly coupled photovoltaic-electrolyzer (PV/El) systems in order to maximize the hydrogen production or to minimize energy transfer loss between photovoltaic devices and the electrolyzer. Nevertheless an easy and efficient approach still... 

    Kalman filter based packet loss replacement in presence of additive noise

    , Article 2012 25th IEEE Canadian Conference on Electrical and Computer Engineering: Vision for a Greener Future, CCECE 2012 ; 2012 ; 9781467314336 (ISBN) Miralavi, S. R ; Ghorshi, S ; Tahaei, A
    2012
    Abstract
    A major problem in real-time packet-based communication systems, is misrouted or delayed packets which results in degraded perceived voice quality. If packets are not available on time, the packets are considered as lost. The easiest solution in a network terminal receiver is to replace silence for the duration of lost speech segments. In a high quality communication system, to avoid degradation in speech quality due to packet loss, a suitable method or algorithm is needed to replace the missing segments of speech. In this paper, we introduce an adaptive filter for replacement of lost speech segment. In this method Kalman filter as a state-space based method will be used to predict the... 

    Investigation of Mesh Sensitivity Influence to Determine Crack Characteristic by Finite Element Methods

    , Article Journal of Failure Analysis and Prevention ; Volume 16, Issue 3 , 2016 , Pages 506-512 ; 15477029 (ISSN) Azimi, M ; Mirjavadi, S. S ; Asli, S. A ; Sharif University of Technology
    Springer New York LLC  2016
    Abstract
    In this research, an extended finite element model has been investigated. Investigation of opening and closure stress always has been one of the difficult parameters to analysis of results; therefore, the utilization of finite element methods would be a good and logical alternative for this purpose. In addition, linear elastic fracture criteria are used for validation of numerical results from the simulation. In this work, a detailed analysis of the influence of different parameters in the results of a specific specimen with a semi-elliptical tooling groove in terms of closure and opening stress is presented, and the impact of optimum element size in fracture characteristic in various load... 

    Investigation of the effect of nanosilica on rheological, thermal, mechanical, structural, and piezoelectric properties of poly(vinylidene fluoride) nanofibers fabricated using an electrospinning technique

    , Article Industrial and Engineering Chemistry Research ; Volume 56, Issue 44 , 2017 , Pages 12596-12607 ; 08885885 (ISSN) Haddadi, S. A ; Ahmad Ramazani, S. A ; Talebi, S ; Fattahpour, S ; Hasany, M ; Sharif University of Technology
    2017
    Abstract
    The effects of different nano-SiO2 contents on the rheological properties of poly(vinylidene fluoride) (PVDF) solution and mechanical, thermal, structural, and piezoelectric properties of composite nanofibers were investigated. Results showed an increase in fiber diameter (∼125 to 350 nm) and ∼450% increase in tensile strength as the content of nano-SiO2 particles increased. The degree of crystallinity decreased by 19% as the nano-SiO2 content increased by 2% (w/w). Further investigation demonstrated that silica could significantly improve the piezoelectric properties of PVDF nanofibers as the output voltage showed an increase in the presence of silica attributed to change in the crystalline... 

    A method for real-time safe navigation in noisy environments

    , Article 2013 18th International Conference on Methods and Models in Automation and Robotics, MMAR 2013, Miedzyzdroje ; 2013 , Pages 329-333 ; 9781467355063 (ISBN) Neyshabouri, S. A. S ; Kamali, E ; Niknezhad, M. R ; Monfared, S. S. M. S ; Sharif University of Technology
    2013
    Abstract
    The challenge of finding an optimized and reliable path dates back to emersion of mobile robots. Several approaches have been developed that have partially answered this need. Satisfying results in previous implementations has led to an increased utilization of sampling-based motion planning algorithms in recent years, especially in high degrees of freedom (DOF), fast evolving environments. Another advantage of these algorithms is their probabilistic completeness that guarantees delivery of a path in sufficient time, if one exists. On the other hand, sampling based motion planners leave no comment on safety of the planned path. This paper suggests biasing the Rapidly-exploring Random Trees... 

    A generalization of the swartz equality

    , Article Glasgow Mathematical Journal ; Vol. 56, issue. 2 , May , 2014 , pp. 381-386 ; ISSN: 00170895 Pournaki, M. R ; Fakhari, S. A. S ; Yassemi, S ; Sharif University of Technology
    2014
    Abstract
    For a given (d-1)-dimensional simplicial complex Γ, we denote its h-vector by h(Γ)=(h 0(Γ),h 1(Γ),...,hd (Γ)) and set h -1(Γ)=0. The known Swartz equality implies that if Δ is a (d-1)-dimensional Buchsbaum simplicial complex over a field, then for every 0 ≤ i ≤ d, the inequality ihi (Δ)+(d-i+1)h i-1(Δ) ≥ 0 holds true. In this paper, by using these inequalities, we give a simple proof for a result of Terai (N. Terai, On h-vectors of Buchsbaum Stanley-Reisner rings, Hokkaido Math. J. 25(1) (1996), 137-148) on the h-vectors of Buchsbaum simplicial complexes. We then generalize the Swartz equality (E. Swartz, Lower bounds for h-vectors of k-CM, independence, and broken circuit complexes, SIAM J....