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    Transmission loss allocation using normalized loss weight factors

    , Article 10th International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2008, Rincon, 25 May 2008 through 29 May 2008 ; 2008 , Pages 224-228 ; 9781934325216 (ISBN) Keshmiri, S. N ; Ehsan, M ; Sharif University of Technology
    2008
    Abstract
    One of the major problems in liberalized power markets is loss allocation. In this paper, a new method for allocating transmission losses to pool market participants is proposed. The proposed method is fundamentally based on Bialek's "Tracing the flow of electricity" method. The losses is allocated to market participants using the loss weight factors (LWFs) which are obtained from the square current magnitude and Z-bus matrix. The LWF method is based on a solved load flow and strongly emphasizes on current magnitude while considers network topology. The method has been implemented and tested on several networks and one sample summarized in the paper. The results show that the method has an... 

    Transmission loss allocation using normalized loss weight factors

    , Article 3rd International Conference on Deregulation and Restructuring and Power Technologies, DRPT 2008, Nanjing, 6 April 2008 through 9 April 2008 ; 2008 , Pages 431-435 ; 9787900714138 (ISBN) Keshmiri, S. N ; Ehsan, M ; Sharif University of Technology
    2008
    Abstract
    One of the major problems in liberalized power markets is loss allocation. In this paper, a new method for allocating transmission losses to pool market participants is proposed. The proposed method is fundamentally based on Bialek's "Tracing the flow of electricity" method. The losses is allocated to market participants using the loss weight factors (LWFs) which are obtained from the square current magnitude and Z-bus matrix. The LWF method is based on a solved load flow and strongly emphasizes on current magnitude while considers network topology. The method has been implemented and tested on several networks and one sample summarized in the paper. The results show that the method has an... 

    Interpretation of CPT in unsaturated sands under drained conditions: A numerical study

    , Article International Journal for Numerical and Analytical Methods in Geomechanics ; Volume 45, Issue 18 , 2021 , Pages 2732-2755 ; 03639061 (ISSN) Keshmiri, E ; Ahmadi, M. M ; Sharif University of Technology
    John Wiley and Sons Ltd  2021
    Abstract
    A finite difference-based numerical model simulating the cone penetration process in unsaturated sands is presented. Mohr–Coulomb model (MCM) with simple modifications and Sun model (SM) were implemented to capture the unsaturated sand behaviour. It was shown that the cone tip resistance values resulting from the two models were fairly comparable. Predicted cone tip resistance values in dry, saturated and unsaturated sands using MCM were validated by the results of field and calibration chamber tests. Sensitivity analyses were performed, and the influence of parameters including relative density, mean effective stress and apparent cohesion due to suction on the tip resistance was... 

    Pressuremeter test in unsaturated soils: a numerical study

    , Article SN Applied Sciences ; Volume 3, Issue 4 , 2021 ; 25233971 (ISSN) Keshmiri, E ; Ahmadi, M. M ; Sharif University of Technology
    Springer Nature  2021
    Abstract
    The paper presents a numerical analysis of pressuremeter test in unsaturated cohesive soils. In practice, pressuremeter is commonly expanded up to 10–15% cavity strains. At these strains, limit pressure is not usually reached, and its value is estimated by extrapolation. Accordingly, authors suggest using cavity pressure at 10% strain (P10) for the interpretation of pressuremeter test rather than limit pressure. At this strain, it is also assured that plastic strain occurs around the cavity, which is crucial for the interpretations. In unsaturated soils, the moisture at which a soil is tested has a noticeable influence on the pressuremeter cavity pressure, and consequently, on the magnitude... 

    Parametric stability of symmetrically laminated composite super-elliptical plates

    , Article Journal of Composite Materials ; Volume 50, Issue 28 , 2016 , Pages 3935-3951 ; 00219983 (ISSN) Ghaheri, A ; Nosier, A ; Keshmiri, A ; Sharif University of Technology
    SAGE Publications Ltd  2016
    Abstract
    Static and parametric stability of thin symmetrically laminated composite super-elliptical plates resting on Winkler-type foundation and subjected to uniform in-plane harmonic loads, under clamped, simply supported and free boundary conditions, are investigated based on the classical laminated plate theory. The governing equations are obtained from a variational approach and then the classical Ritz method is used to reduce the problem into a set of coupled Mathieu-Hill equations. Hsu's technique is utilized to determine the dynamic instability regions of principal and combination resonance frequencies. Extensive numerical data are provided to examine the effects of plate aspect ratio,... 

    A Numerical Approach for Determination of Soil Parameters by Pressuremeter Test

    , M.Sc. Thesis Sharif University of Technology Keshmiri, Ehsan (Author) ; Ahmadi, Mohammad Mehdi (Supervisor)
    Abstract
    In-situ tests are strongly recommended in site investigations, since laboratory studies are not sufficient for precise determination of soil parameters. Effects of soil disturbance on laboratory studies questions the validation of obtained soil parameters. In the in-situ tests, soil experience less disturbance and these tests are conducted in stress levels resembling to soil initial horizontal and vertical stresses. Also more volume of soil is tested by in-situ tests in comparison to laboratory studies. Pressuremeter instrument was invented by Menard (1954). In this test, a flexible cylinder is expanded in the cavity under fluid pressure and the volume and stress changes of the cavity are... 

    Numerical Modeling of Pressuremeter, Cone Penetration and Plate Load Tests in Unsaturated Soils

    , Ph.D. Dissertation Sharif University of Technology Keshmiri, Ehsan (Author) ; Ahmadi, Mohammad Mehdi (Supervisor)
    Abstract
    One of the important issues that has been the focus of various researchers in the interpretation of in-situ test results over the past decades is the effect of soil moisture content and degree of saturation on in-situ test results. To date, few methods have been presented for interpreting in-situ test results in unsaturated soils. In this research, in order to model the stress-strain behavior of unsaturated soils, modified Mohr-Coulomb (MC), Barcelona Basic (BB) and Sun models are implemented into FLAC software (which is based on finite difference method) by coding with FISH language. Then, the pressuremeter test, plate load test and cone penetration test are numerically simulated in FLAC... 

    Boundary integral equation analysis of an inhomogeneous medium made of functionally graded materials

    , Article Advanced Materials Research ; Volume 685 , 2013 , Pages 285-289 ; 10226680 (ISSN) ; 9783037856765 (ISBN) Ashrafi, H ; Bahadori, M. R ; Keshmiri, H ; Shariyat, M ; Sharif University of Technology
    2013
    Abstract
    The present work develops direct graded boundary integral equation formulation for behavior investigation of the inhomogeneous media made of functionally graded materials. The isoparametric boundary elements, the elastostatic governing equations and a weighted residual technique are implemented with the material characteristics that vary continuously along a given dimension. The resulting algorithm is capable of solving the quasistatic problems for elastic functionally graded media with a variety of the boundary conditions and loadings. The inhomogeneous media is made of a ceramic-metal mixture, in which the material properties vary continuously according to a power law graded distribution... 

    Enzymes : catalysis, kinetics and mechanisms

    , Book Punekar, N. S
    Springer  [2018]

    DNA binding and recognition of a CC mismatch in a DNA duplex by water-soluble peptidocalix[4]arenes: synthesis and applications

    , Article Organic Letters ; Volume 18, Issue 19 , 2016 , Pages 4766-4769 ; 15237060 (ISSN) Alavijeh, N. S ; Zadmard, R ; Balalaie, S ; Alavijeh, M. S ; Soltani, N ; Sharif University of Technology
    American Chemical Society  2016
    Abstract
    Water-soluble peptidocalix[4]arenes were synthesized by the introduction of arginine-rich narrow groove-binding residues at lower rims through solid-phase synthesis. The study of binding of these water-soluble bidentate ligands to well-matched and mismatched DNA duplexes by fluorescent titrations, ethidium bromide (EB) displacement assays, DNA-melting experiments, and circular dichroism (CD) analysis revealed a sequence-dependent groove-binding mechanism  

    A meta user interface for interaction with mixed reality environments

    , Article 2015 IEEE International Symposium on Haptic, Audio and Visual Environments and Games, HAVE 2015 - Proceedings, 11 October 2015 ; October , 2015 , Page(s): 1 - 6 ; 9781467391757 (ISBN) Mostafazadeh, A ; Shirehjini, A. A. N ; Daraei, S ; Khojasteh, N ; Shirmohammadi, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2015
    Abstract
    The aim of this paper is the design and development of a novel user interface to interact with a meta system. Our focus is rather on interacting with Ambient Intelligence as a whole, which would for example enable users to influence the overall behaviors and attributes of dynamic device compositions. We call such interfaces Meta User Interfaces. The design details of a proposed user interface as well as a cognitive walkthrough evaluation are presented in this paper  

    Fabrication and characterization of biaxially electrospun collagen/alginate nanofibers, improved with Rhodotorula mucilaginosa sp. GUMS16 produced exopolysaccharides for wound healing applications

    , Article International Journal of Biological Macromolecules ; Volume 196 , 2022 , Pages 194-203 ; 01418130 (ISSN) Ashraf, S. S ; Parivar, K ; Hayati Roodbari, N ; Mashayekhan, S ; Amini, N ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Fabrication of scaffolds with enhanced mechanical properties and desirable cellular compatibility is critical for numerous tissue engineering applications. This study was aimed at fabrication and characterization of a nanofiber skin substitute composed of collagen (Col)/sodium alginate (SA)/ polyethylene oxide (PEO)/Rhodotorula mucilaginosa sp. GUMS16 produced exopolysaccharides (EPS) were prepared using the biaxial electrospinning technique. This study used collagen extracted from the bovine tendon as a natural scaffold, sodium alginate as an absorber of excess wound fluids, and GUMS16 produced exopolysaccharides as an antioxidant. Collagen was characterized using FTIR and EDS analyses. The... 

    Axial potential mapping of optical tweezers for biopolymer stretching: The bead size matters

    , Article Optics Letters ; Volume 38, Issue 5 , 2013 , Pages 685-687 ; 01469592 (ISSN) Ahmadi, A ; Reihani, S. N. S ; Sharif University of Technology
    2013
    Abstract
    Optical tweezers (OT) are widely used for pico (and femto)-Newton range force measurements. The appropriate choice of the bead size is not well understood for biopolymer stretching applications of OT. We have shown, both by theory and experiment, that wrong choice of the bead size could cause errors as large as 295% in the measured force. We provide a simple map for correct choice of the bead size and the direction of pulling for such applications. There is a good agreement between our theoretical and experimental results  

    Comparison of furfural degradation by different photooxidation methods

    , Article Chemical Engineering Journal ; Volume 139, Issue 3 , 2008 , Pages 482-488 ; 13858947 (ISSN) Borghei, S. M ; Hosseini, S. N ; Sharif University of Technology
    2008
    Abstract
    In this paper, the degradation of C5H4O2 "Furfural" in aqueous solution by photooxidation technology using UV, UV/H2O2, UV/H2O2/O2, UV/H2O2/Fe2+, UV/O2/Fe2+, O3, UV/O3 process and also oxidation by sodium hypochlorite was investigated in a lab-scale batch photo-reactor. To evaluate the performance of different processes, the efficiency of furfural degradation was studied by measuring the total organic carbon (TOC) throughout the experimentation. Results show that compare to other reactions studied in this research, the UV/H2O2 is a simple and effective process for furfural degradation and presence of Fe2+ ions (UV/H2O2/Fe2+) enhanced removal of furfural in solution. The influence of... 

    Synthesis of soluble N-functionalized polysaccharide derivatives using phenyl carbonate precursor and their application as catalysts

    , Article Starch/Staerke ; Volume 63, Issue 12 , 2011 , Pages 780-791 ; 00389056 (ISSN) Pourjavadi, A ; Seidi, F ; Afjeh, S. S ; Nikoseresht, N ; Salimi, H ; Nemati, N ; Sharif University of Technology
    2011
    Abstract
    Soluble N-functionalized basic and cationic polysaccharides have been synthesized using polysaccharide phenyl carbonate as a precursor. The products and intermediates were thoroughly characterized by conventional methods. The quaternization of amino intermediates in various conditions was studied. Moreover, the potential of basic polymers as green and selective catalysts in Knoevenagel reaction was investigated. In all cases, only one isomer was obtained  

    Reducing traffic congestion and increasing sustainability in special urban areas through one-way traffic reconfiguration

    , Article Transportation ; 2021 ; 00494488 (ISSN) Karimi, H ; Ghadirifaraz, B ; Shetab Boushehri, S. N ; Hosseininasab, S. M ; Rafiei, N ; Sharif University of Technology
    Springer  2021
    Abstract
    In the contemporary sustainable urban set up, one of the critical issues adversely affecting the quality of life in urban areas and inflicting immense costs on cities is traffic congestion. Traffic congestion is an outgrowth of increased traffic flow in certain locations of large cities. Recently, urban decision-makers and transportation planners resort to one-way traffic system as an effective traffic management strategy, which has a profound effect on reducing traffic congestion and improving traffic flow, leading to urban sustainability. In the present paper, the authors endeavored to develop a novel methodological framework based on optimization techniques in order to mitigate traffic... 

    Reducing traffic congestion and increasing sustainability in special urban areas through one-way traffic reconfiguration

    , Article Transportation ; Volume 49, Issue 1 , 2022 , Pages 37-60 ; 00494488 (ISSN) Karimi, H ; Ghadirifaraz, B ; Shetab Boushehri, S. N ; Hosseininasab, S. M ; Rafiei, N ; Sharif University of Technology
    Springer  2022
    Abstract
    In the contemporary sustainable urban set up, one of the critical issues adversely affecting the quality of life in urban areas and inflicting immense costs on cities is traffic congestion. Traffic congestion is an outgrowth of increased traffic flow in certain locations of large cities. Recently, urban decision-makers and transportation planners resort to one-way traffic system as an effective traffic management strategy, which has a profound effect on reducing traffic congestion and improving traffic flow, leading to urban sustainability. In the present paper, the authors endeavored to develop a novel methodological framework based on optimization techniques in order to mitigate traffic... 

    Dynamic relay selection and resource allocation in cooperative networks based on OFDM

    , Article 17th European Wireless Conference 2011, EW 2011 ; 2011 , Pages 328-332 ; (Print ISBN): 978-3-8007-3343-9 Javidbakht, O ; Alizadeh, N. N ; Razavizadeh, S. M ; Sharif University of Technology
    2011
    Abstract
    In this paper, we are planning to introduce a new method for relay selection and resource allocation in OFDM-based cooperative networks. Up to now, there have been relatively few works clearly concentrating on the combination of relay selection and resource allocation in such networks. In our work, a network with a single transmitter, a single receiver and a group of relays is considered. Relays work on Amplify and Forward (AF) method and there is no direct link between the transmitter and the receiver. The optimization problem is to maximize the throughput of the receiver with constraints on the amounts of the power of the transmitter and relays, and subcarriers. We will introduce an... 

    H0 tension as a hint for a transition in gravitational theory

    , Article Physical Review D ; Volume 99, Issue 10 , 2019 ; 24700010 (ISSN) Khosravi, N ; Baghram, S ; Afshordi, N ; Altamirano, N ; Sharif University of Technology
    American Physical Society  2019
    Abstract
    We propose a cosmological model, üΛCDM, based on "über gravity," which is a canonical ensemble average of many theories of gravity. In this model, we have a sharp transition from (a purely) ΛCDM era to a phase in which the Ricci scalar is a constant. This transition occurs when the Ricci scalar reaches a critical scale or alternatively a transition redshift, z. We use the observations of baryonic acoustic oscillations and supernovae Ia, as well as the cosmic microwave background data to constrain üΛCDM. This yields H0=70.6-1.3+1.1 km/s/Mpc, ωm=0.2861±0.0092, and z=0.537-0.375+0.277, providing a marginally better fit with a Akaike information criterion of 0.8. Therefore, üΛCDM can ease the H0... 

    The ODYSSEY approach to early simulation-based equivalence checking at ESL level using automatically generated executable transaction-level model

    , Article Microprocessors and Microsystems ; Volume 32, Issue 7 , 2008 , Pages 364-374 ; 01419331 (ISSN) Goudarzi, M ; Hessabi, S ; MohammadZadeh, N ; Zainolabedini, N ; Sharif University of Technology
    2008
    Abstract
    Design technology is expected to rise to electronic system-level (ESL). This necessitates new techniques and tools for synthesizing ESL designs and for verifying them before and after ESL synthesis. A promising verification strategy for future very complex designs is to initially verify the design at the highest level of abstraction, and then check the equivalence of the lower level automatically generated models against that initial golden model. We present one such approach to simulation-based functional verification implemented in our ESL design methodology called ODYSSEY. Our ESL synthesis tool generates a transaction-level model (TLM) at TLM level 2 (i.e., design with partial timing)...