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Role of bazaars as a unifying factor in traditional cities of Iran： The Isfahan bazaar

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Frontiers of Architectural Research 2014年第1期3卷 10-19页

作者： Mohammadreza Pourjafar Masoome Amini Elham Hatami Yarzaneh Mohammadjavad Mahdavinejad faculty of art & architecture-tarbiat modares university Tehran Iran architecture Fuculty of Art and Architecture Turbiat Modares University Tehran Iran Fuculty of art and architecture Khorasgan Azad University Isfuhan Iran

A city is a vital organism that lives and grows （ike other organisms. Therefore, implementing development plans that would provide a sense of unity and integration in relation to the city as a who（e is necessary. Traditional Iranian architecture is full of samples evolved during the course of Iranian history that can serve as architectural paragons of the city. In Iran＇s traditional cities, a sense of unity exists in various urban areas. The traditional city of Isfahan is one of the most valuable samples and was selected as the case study in this research. According（y, the most important questions of this research are as follows：（1） What is the role of bazaars in creating a sense of unity in the traditional cities of Iran？（2） How do bazaars play out their ro（e in the integration of these cities？ This research focuses on the concept of a ＂traditional city＂ to determine the role of bazaars in such cities. The results show that bazaars are crucial in giving a sense of integrity to the concept of a traditional Iranian city. Bazaars provide cohesion among the different parts of cities, such as residential areas, as well as socio-political and trade centers. This condition means that traditional bazaars play two important roles in traditional cities：（1） they interconnect the different parts of thecity＇s physical structure; and （2） the crucial role of bazaars in a city＇s socia（ and cultural structure brings about unity among the citizens in the city. Bazaars as a unifying etement connect the main urban functions and guarantee the city＇s economic and social rife.

关键词： Traditional city Bazaar Development axes Isfahan

Numerical Modeling of the Stability of Horizontal Multidrain Oil Wells

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China Ocean Engineering 2015年第5期29卷 719-732页

作者： Ayub ELYASI Kamran GOSHTASBI faculty of Engineering Tarbiat Modares University

The stability of the horizontal multidrain wells is a crucial issue and several factors are involved in this matter, including in-situ stresses, magnitude and distribution as well as the mainbore trajectories. In this paper, this issue is evaluated by assuming different circumstances for the above mentioned factors, based on finite difference threedimensional modeling by using the finite difference numerical software, FLAC3 D. The stability of the mainbore and lateral branches is analyzed based on the Normalized Yielded Zone Area（NYZA） criterion, i.e. the ratio of the surrounding yielded cross-sectional area to the initial area of the well. Optimum mud pressures are obtained in the mainbore and lateral branches in different mainbore trajectories under three in-situ stress regimes. In addition, the stability of the junction where the lateral branches are bifurcated from the mainbore is assessed in those situations. The optimum trajectory of the mainbore, in which the junction has obtained the most stable condition, is selected in each stress regime. It was concluded that in the Normal Faulting（NF） stress regime, the mainbore and junction stability varies in relation to the mainbore trajectories, inversely. However, in the other two stress regimes, i.e. Strike Slip（SS） and Reverse Faulting（RF）, the variations of the mainbore and junction stability are in the same trend with respect to the mainbore trajectory deviations.

关键词： multidrain wells in-situ stresses NYZA mainbore lateral branches

Exploring patterns and consequences of land consumption in a coastal city-region

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Ecological Processes 2022年第1期11卷 669-693页

作者： Hashem Dadashpoor Zahra Hasankhani Urban and Regional Planning DepartmentFaculty of Arts and ArchitectureTarbiat Modares UniversityTehranIran Researcher of Urban and Regional Planning Faculty of Arts and ArchitectureTarbiat Modares UniversityTehranIran

Background:The rapid expansion of built-up areas and land consumption with unsustainable spatial patterns in coastal urban areas has become a global major concern due to its far-reaching consequences for human daily life,environmental sustainability,and living ***,the research on this phenomenon in these areas has received less *** fill this gap,we conducted a study to explore the spatial patterns of land consumption at both micro-and macro-levels and to evaluate its consequences in terms of sustainable development in a coastal city-region of Mazandaran Province in northern *** achieve these two goals,we combined two methods of urban land density function and landscape expansion index(LEI)to explore spatial patterns of land consumption and also evaluated the sustainability of the region with two methods of the hierarchical analytical process(AHP)and urban sustainability index(USI).Results:The spatial patterns of land consumption in the city-region of Mazandaran from 1996 to 2016 at the macro-level changed from a decentralized-sprawl to a centralized-sprawl *** the micro-level,the dominant spatial pattern of land consumption in the city-region changed gradually from the outlying pattern towards the edge expansion and infilling ***,the spatial pattern of the built-up patches in the majority of the urban areas had conformity with the dominant pattern of the ***,the spatial patterns of land consumption in the region were in an unsustainable state and were changing towards more *** absence of urban containment policies and plans could lead to further destruction of the natural environment and increase its ***:Our results indicate that the urban areas of the coastal Mazandaran have the same behavior in the spatial pattern of land consumption at the macro-and micro-levels and all are in the same direction and follow the dominant pattern of the region.

关键词： Land consumption Land use change Spatial pattern Urban growth Sprawl Sustainability Consequence Urban area

Evaluation of boring machine performance with special reference to geomechanical characteristics

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 615-619页

作者： K. Goshtasbi M. Monjezi P. Tourgoli faculty of Engineering Tarbiat Modares University

The duration of tunneling projects mostly depends on the performance of boring machines. The performance of boring machines is a function of advance rate, which depends on the machine characterizations and geomechanical properties of rock mass. There were various theoretical and empirical models for estimating the advance rate. In this paper, after determining the geomechanical properties of rock mass encountered in the Isfahan metro tunnel, the performance of the roadheader and tunnel boring machine （TBM） were then evaluated using various models. The calculation results show that the average instantaneous cutting rate of the roadheader in sandstone and shale are 42.8 and 74.5 m^3/h respectively. However the actual values in practice are 34.2 and 51.3 m^3/h. The operational cutting rate of the roadheader in sandstone and shale are 8.2 and 9.7 m^3/h respectively, but the actual values are 6.5 and 6.7 m^3/h. The penetration rate of the TBM in shale is predicted to be 50-60 mm/round.

关键词： performance prediction roadheader cutting rate specific energy tunnel boring machine penetration rate

Multi-objective robot motion planning using a particle swarm optimization model

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Journal of Zhejiang university-Science C(Computers and Electronics) 2010年第8期11卷 607-619页

作者： Ellips MASEHIAN Davoud SEDIGHIZADEH faculty of Engineering Tarbiat Modares University

Two new heuristic models are developed for motion planning of point robots in known *** first model is a combination of an improved particle swarm optimization (PSO) algorithm used as a global planner and the probabilistic roadmap (PRM) method acting as a local obstacle avoidance *** the PSO component,new improvements are proposed in initial particle generation,the weighting mechanism,and position-and velocity-updating ***,two objective functions which aim to minimize the path length and oscillations,govern the robot’s movements towards its *** PSO and PRM components are further intertwined by incorporating the best PSO particles into the randomly generated *** second model combines a genetic algorithm component with the PRM *** this model,new specific selection,mutation,and crossover operators are designed to evolve the population of discrete particles located in continuous *** comparisons of the developed models with each other,and against the standard PRM method,show the advantages of the PSO method.

关键词： Robot motion planning Particle swarm optimization Probabilistic roadmap Genetic algorithm

Low Complexity Adaptive Equalizers for Underwater Acoustic Communications

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China Ocean Engineering 2014年第4期28卷 529-540页

作者： Masoumeh SOFLAEI Paeiz AZMI faculty of Electrical and Computer Engineering Tarbiat Modares University

Interference signals due to scattering from surface and reflecting from bottom is one of the most important problems of reliable communications in shallow water channels. To solve this problem, one of the best suggested ways is to use adaptive equalizers. Convergence rate and misadjustment error in adaptive algorithms play important roles in adaptive equalizer performance. In this paper, affine projection algorithm （APA）, selective regressor APA（SR-APA）, family of selective partial update （SPU） algorithms, family of set-membership （SM） algorithms and selective partial update selective regressor APA （SPU-SR-APA） are compared with conventional algorithms such as the least mean square （LMS） in underwater acoustic communications. We apply experimental data from the Strait of Hormuz for demonstrating the efficiency of the proposed methods over shallow water channel. We observe that the values of the steady-state mean square error （MSE） of SR-APA, SPU-APA0 SPU-normalized least mean square （SPU-NLMS）, SPU-SR-APA0 SM-APA and SM-NLMS algorithms decrease in comparison with the LMS algorithm. Also these algorithms have better convergence rates than LMS type algorithm.

关键词： underwater acoustic communication affine projection algorithm (APA) selective regressor APA(SR-APA) selective partial update APA(SPU-APA) SPU-normalized least mean square (SPU-NLMS) algorithm set-membership APA(SM-APA) set-membership NLMS(SM-NLMS) algorithm

Soil-Structure Interaction Analysis of Jack-up Platforms Subjected to Monochrome and Irregular Waves

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China Ocean Engineering 2015年第1期29卷 65-80页

作者： Maziar Gholami KORZANI Ali Akbar AGHAKOUCHAK faculty of Civil and Environmental Engineering Tarbiat Modares University

As jack-up platforms have recently been used in deeper and harsher waters, there has been an increasing demand to understand their behaviour more accurately to develop more sophisticated analysis techniques. One of the areas of significant development has been the modelling of spudean performance, where the load-displacement behaviour of the foundation is required to be included in any numerical model of the structure. In this study, beam on nonlinear winkler foundation （BNWF） modeling--which is based on using nonlinear springs and dampers instead of a continuum soil media--is employed for this purpose. A regular monochrome design wave and an irregular wave representing a design sea state are applied to the platform as lateral loading. By using the BNWF model and assuming a granular soil under spudcans, properties such as soil nonlinear behaviour near the structure, contact phenomena at the interface of soil and spudcan （such as uplifting and rocking）, and geometrical nonlinear behaviour of the structure are studied. Results of this study show that inelastic behaviour of the soil causes an increase in the lateral displacement at the hull elevation and permanent unequal settlement in soil below the spudcans, which are increased by decreasing the friction angle of the sandy soil. In fact, spudeans and the underlying soil cause a relative fixity at the platform support, which changes the dynamic response of the structure compared with the case where the structure is assumed to have a fixed support or pinned support. For simulating this behaviour without explicit modelling of soil-structure interaction （SSI）, moment- rotation curves at the end of platform legs, which are dependent on foundation dimensions and soil characteristics, are obtained. These curves can be used in a simplified model of the platform for considering the relative fixity at the soil- foundation interface.

关键词： jack-up platforms wave loading nonlinear dynamic analysis soil-structure interaction (SS1) beam on nonlinear winkler foundation (BNWF)

Kinetic study on photocatalytic degradation of Acid Orange 52 in a baffled reactor using TiO_2 nanoparticles

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Journal of Environmental Sciences 2019年第5期31卷 213-224页

作者： Payam Zanganeh Ranjbar Bita Ayati Hossein Ganjidoust Civil and Environmental Engineering faculty Tarbiat Modares University

In this study, a baffled photocatalytic reactor was used for the treatment of colored wastewater containing the azo dye of Acid Orange 52(AO52). A study on the active species of the photocatalytic process using TiO_2 nanoparticles indicated that hydroxyl radical and superoxide have the greatest contribution to the dye degradation process *** that a level of biological oxygen demand/chemical oxygen demand(BOD5/COD) equal to 0.4 was achieved after about 5 hr from the beginning of the experiment, the reactor seems to be capable of purifying the wastewater containing AO52 dye after this time in order to discharge into a biological treatment system to continue the treatment *** results of the liquid chromatography-mass spectrometry(LC-MS) test showed that during the first 4 hr of the experiment, with the breakdown of the azo bond, the contaminant was decomposed into the benzene annular compounds with less toxicity indicating a reduction in the toxicity of wastewater after removing the dye agent. The study on the kinetics of these reactions followed the pseudo-first-order kinetic model in all conditions and corresponded well to Langmuir–Hinshelwood model. According to the kinetic model for the simultaneous occurrence of possible pathways, the kinetic constant of production and degradation of intermediate products in optimal conditions was estimated to be between 0.0029 and 0.0391 min^(-1).

关键词： Kinetic study Active species Photocatalyst Decolorization

Effects of Nb Alloying on Nano-Crystallization Kinetics of Fe_(55-x)Cr_(18)Mo_7B_(16)C_4Nb_x(x=0, 3) Bulk Amorphous Alloys

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Journal of Materials Science & Technology 2011年第8期27卷 735-740页

作者： S. Ahmadi H.R. Shahverdi S.S. Saremi faculty of Engineering Department of Materials Science Tarbiat Modares University

Crystallization kinetics of Fe55-xCrzsMo7B10C4Nbx（x= 0, 3） bulk amorphous alloys were analyzed using X-ray diffraction and differential scanning; calorimetric （DSC） tests. In practice, crystallization and growth mechanism were evaluated using DSC tests at four different heating rates （10, 20, 30, and 40 K/rain） and kinetic models. Two-step crystallization behavior was observed when Fe55Cr18MOTB16C4 and Fe52Cr18MoTB16C4Nb3 bulk amorphous alloys were annealed, where Fe36Cr12M010 phase was crystallized in the first step of crystallization. Results show that Fe36Cr12Mo10 and Fe3C phases were crystallized in the structures of the alloys after further annealing： process. Activation energy for the crystallization of Fe36Cr12Mozo phase was measured to be 543 kJ/mol in Fe52Cr18MoTB16C4Nb3 alloy and 375 kJ/mol for Fe55Cr18Mo7B16C4 alloy according to Kissinger-Starink model. Moreover, a two-dimensiona nucleation rate was found in Fe52Cr18Mo7B16C4Nb3 diffusion controlled growth mechanism with decreasing alloy whereas a three-dimensional diffusion controlled growth mechanism with decreasing nucleation rate was found in crystallization of Fe36Crz2Mo10 phase during annealing of Fe55Cr18MoTB16C4 alloy. TEM （transmission electron microscopy） observations reveal that crystalline Fe36Cr12M010 phase nucleated in the structures of the alloys in an average size of 10 nm with completely mottled morphology.

关键词： Avrami exponent Crystallization Kinetic models Growth mechanisms Bulk amorphous alloys