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Open Access Article
1 - On validity of paraxial theory for super-Gaussian laser beams propagating in a plasma
Lalita Devi Hitendra K. Malik -
Open Access Article
2 - Micromagnetic analysis of Heusler alloy-based perpendicular double barrier synthetic antiferromagnetic free layer MTJs
Bahniman Ghosh Kshitij Dwivedi -
Open Access Article
3 - Investigating the effect of geometrical asymmetry on conductance and TMR ratio in the ZnO rock salt-based MTJ: a DFT study
Masoud Ansarino -
Open Access Article
4 - Wind tunnel flow simulation and aerodynamic shape optimization of tall buildings to improve the drag coefficient under wind forces
Abdollah Baghaei Daemei seyed rahman eghbali Hossein Moez Payam BahramiAerodynamic behavior is an important characteristic of tall and ductile buildings, so aerodynamic design can play a key role in reducing the wind effects. A tall building response to wind can be controlled by application of aerodynamic improvements to building’s d MoreAerodynamic behavior is an important characteristic of tall and ductile buildings, so aerodynamic design can play a key role in reducing the wind effects. A tall building response to wind can be controlled by application of aerodynamic improvements to building’s design in order to manipulate the wind flow pattern and break the effective wind force acting on the structure. Traditionally the approach of structural engineers to mitigating wind loading and associated deflections and motions on tall buildings was to stiffen the building with the aim of increasing the natural frequency. Tall buildings are extremely sensitive to the wind. Thus, assessment of wind loads to design these buildings is essential. Monitoring the wind, which is forcing extraordinary tall buildings, is highly challenging. Due to increasing construction in recent decades, the study on wind flow over tall buildings has become a popular subject in theoretical research and applied engineering applications. By looking at recent constructions in Iran, it is obvious that despite the fact that constructing tall buildings is spreading, there is less concentration on environmental factors such as the wind’s aerodynamic. In tall buildings, aerodynamic behavior generally becomes important. The wind-induced building response of tall buildings can be reduced by means of aerodynamic from design and modifications that change the flow pattern around the building or break up the wind affecting the building face. Aerodynamic-based design can be divided into two types, “aerodynamic architectural design” and “aerodynamic architectural modifications” and their subgroups. The accurate estimation of the critical response parameters, such as top floor accelerations and displacements, is of fundamental importance when ensuring reliable designs of tall buildings. Methods to this end are typically set in a modal analysis framework and therefore require the estimation of the generalized forcing functions. Tall buildings are particularly prone to dynamic excitations such as those from natural disasters like strong winds and earthquakes, and this has become an especially important design issue. One way to minimize wind-induced vibrations of tall buildings is to focus more on their shapes in the design stage. Investigated aerodynamic forces and wind pressures acting on tall buildings with various unconventional configurations. The proposed of this research, investigation of aerodynamic shape optimization on tall buildings in order to reduce drag force. The aerodynamic forms such as a set-back, tapered and helical (twisted) and also aerodynamic modifications such as a chamfered corner, rounded corner and recessed corner to control and reduce wind forces and vortices on tall buildings are considered. On this basis, the study was carried out with numerical simulation of wind tunnel test on 29 building models. In order to construct 3D models, AutoCAD 2014 software was deployed and also to numerically simulate wind tunnel Autodesk Flow Design 2014 is used. Building samples were entered into the software via format FBX. The results showed that for a tall building with a triangular footprint and height of about 150 meters, base shape with chamfered corners of aerodynamic modification and tapered of aerodynamic form can have the best aerodynamic behavior against wind forces. Manuscript profile -
Open Access Article
5 - Investigating the wind-induced effects on Tall Buildings to reduce Drag Coefficient through Large Eddy Simulation (LES)
Najmeh Mastari Farahani Abdollah Baghaei Daemei Payam Madelat Seyedeh Maryam Abbaszadegan -
Open Access Article
6 - Safety and biological factor Assessment in crisis management of urban tunnel
Leila Abbaszadeh Tavassoli Azadeh Nekooei Esfahani Hasti BorgheipourBackground and Objective: Urban Expansion and problems regarding urban life raise the necessity of providing actionable strategies to improve urban inhabitants’ life. Today, with increasing tunnel constructions, safety in tunnels has been the issue for engineers, MoreBackground and Objective: Urban Expansion and problems regarding urban life raise the necessity of providing actionable strategies to improve urban inhabitants’ life. Today, with increasing tunnel constructions, safety in tunnels has been the issue for engineers, government officials and authorities. In order to standardize and safety enhancement, safety assessment is the first priority to adopt relevant measures to improve safety level in tunnels. Generally, regarding to the limited spaces in urban tunnels, accidents in tunnels may result in more critical conditions. Occurring of these accidents may disturb the tunnel’s function, which may lead to fire, respiratory problems etc. Given to critical condition after the accidents, therefore, it is required to adopt appropriates methods for safety factor assessment in crisis management of tunnels. The present study address safety and biological factor assessment in crisis management of urban tunnels after that we would investigate the differences between Tohid, Resalat and Shohadaie Qazeh tunnels. Method: To analyze data, Analytic Hierarchy Process (AHP) has been used. Findings: The highest level of risk associated with Tohid tunnel and the lowest level of risk associated with Shohadaie Qazeh tunnels. Discussion and Conclusion: The results of research in 1396 show that the ventilation system has the highest weight and drainage has the lowest weight and Tohid tunnel has the first rank. Manuscript profile -
Open Access Article
7 - Presenting the developed model of Benish by using tunneling phenomena based on artificial neural network technique and particle swarm optimization algorithm to identifying profit manipulating companies
Farhad Azadi Mehrdad GhanbarI Babak Jamshidi navid Javad MasodiToday, profit rates and the possibility of managing and manipulating the profits are clear to all, and researchers have always sought solutions to remove the uncertainties facing investors and stakeholders when making their financial decisions. To clarify users' decisio MoreToday, profit rates and the possibility of managing and manipulating the profits are clear to all, and researchers have always sought solutions to remove the uncertainties facing investors and stakeholders when making their financial decisions. To clarify users' decision path of financial data users, Beneish (1999) has developed a profit-management predicting model that has yielded different results in different societies. Thus, this article aims to optimize and localize Beneish’s model by adding the Tunneling variable to Beneish’s variable and using a modern neural network and particle swarm algorithms. The statistical research population consisted of 196 companies listed at the Tehran Stocks Exchange from 2014 to 2019. The research method was a descriptive-library method in which the variables are interrelated through the causal-correlational method. From an objective point of view, it is an Ex-Post Facto research design. To analyze the data, the regression method and artificial neural and the PSO algorithms were used. The model analysis results suggested that all financial ratios had significant effects on Beneish’s profit management, as the Tunneling phenomenon and the financial leverage had the highest and lowest effects on predicting Beneish’s profit management, respectively. Manuscript profile -
Open Access Article
8 - Investigation of the Structural and Electrical Properties of Star Shape Manganese Thin Films with 3-fold and 4-fold Symmetries
Fatemeh Abdi -
Open Access Article
9 - Theoretical investigation of tautomerisation of 3-Amino-1H-1,2,4-Triazol-5(4H)-One by using quantum calculations by DFT method.
بهزاد چهکندیدر این تحقیق بررسی توتومریزاسیون و حالتهای گذار مولکول 3-آمینو-1H-4،2،1- تریآزول-5)4H (- اٌن که حاصل از انتقالات 1و3 پروتون بین اتم های اکسیژن و نیتروژن است با استفاده از محاسبات کوانتومی در سطح محاسباتیDFT-B3LYP/6-311++G(d,p)، در فاز گازی و در محیطی با حضور یک و دو م Moreدر این تحقیق بررسی توتومریزاسیون و حالتهای گذار مولکول 3-آمینو-1H-4،2،1- تریآزول-5)4H (- اٌن که حاصل از انتقالات 1و3 پروتون بین اتم های اکسیژن و نیتروژن است با استفاده از محاسبات کوانتومی در سطح محاسباتیDFT-B3LYP/6-311++G(d,p)، در فاز گازی و در محیطی با حضور یک و دو مولکول آب انجام شده است. بدین منظور ساختار بهینه توتومرهای مختلف مولکول مورد نظر بدست آمدهاند. همچنین با استفاده از محاسبات فرکانس در سطح محاسباتی مشابه، خواص ترمودینامیکی تعادلهای مختلف توتومری از قبیل E∆، H∆، G∆ وKeq بدست آمدهاند. سپس با استفاده از روشهای QST2 و QST3 حالت های گذار تعادلهای توتومری مختلف مولکول3-آمینو-1H-4،2،1- تریآزول-5)4H (- اٌن و مقادیر سینتیکی و ترمودینامیکی آنها محاسبه شدهاند. اثرات تونلزنی نیز بر روی سرعت واکنشهای مربوطه بررسی شدهاند. نتایج نشان میدهند ثابت سرعت واکنشهای توتومری مورد بررسی نسبت به اثرات تونلزنی حساسیت بالایی دارند و سرعت واکنش های توتومری در حدود چهار تا پنج برابر افزایش مییابند. همچنین محاسبات حالت گذارنشان می دهند در غیاب مولکولهای آب سد انرژی مقدار بالایی دارد و سرعت واکنش های توتومری عمدتاً بدون حضور کاتالیزور خیلی آهسته بوده به عبارتی انجامپذیر نیستند. Manuscript profile -
Open Access Article
10 - Investigation of C-O tautomerism in a derivative of Flucytosine: A DFT study
بهزاد چهکندیIn this research investigation of tautomerism and transition states of 6-Hydroxy 5-Flourocytosine from 1,3 proton transfer between oxygen and carbon atoms in the gas phase and in solution and in a micro hydrated environment with 1-3 water molecules was performed by quan MoreIn this research investigation of tautomerism and transition states of 6-Hydroxy 5-Flourocytosine from 1,3 proton transfer between oxygen and carbon atoms in the gas phase and in solution and in a micro hydrated environment with 1-3 water molecules was performed by quantum calculations at the DFT/B3LYP/6-31++G(d,p) level of theory. For this purpose, the optimized geometries of various tautomers of the desired molecule were obtained. Also by using frequency calculations at the same level thermodynamic properties of different tautomeric equilibriums such as ΔE, ΔH, ΔG and Keq were obtained. Then transition states of various tautomeric interconversion of 6-Hydroxy 5-Flourocytosine and it’s kinetic and thermodynamic amounts were calculated by QST2 and QST3 methods. And also the tunneling effects on rates of reaction were investigated. The results show in both gas phase and solution, rate constants of tautomeric reactions have high sensitivity on tunneling effects and rate of tautomeric interconversion increase by about five or more. Also transition state calculations show in absence of water assisted molecules the tautomeric interconversion reacctions have high barrier energy and so are very slow, in other word they can not be done Manuscript profile -
Open Access Article
11 - Design and Realization of a Junction-less TFET for Analog and Digital Applications Based on Strain Engineering
Fayzollah Khorramrouze Seyed Ali Sedigh Ziabari Ali Heydari -
Open Access Article
12 - Simulation and Optimization of Dual Gate - Dual Material Tunnel Transistor
Reza Talebzadeh Javad Hasanvand Ali MirIn this paper, we designed and simulated a new TFET. Due to the band-to-band tunneling current mechanism, the TFETs show a low current and subthreshold slope of less than 60mV/dec. As a result, they can be a suitable alternative to MOSFET for use in low-power switching MoreIn this paper, we designed and simulated a new TFET. Due to the band-to-band tunneling current mechanism, the TFETs show a low current and subthreshold slope of less than 60mV/dec. As a result, they can be a suitable alternative to MOSFET for use in low-power switching circuits. But its main disadvantage is its low on-state current compared to MOSFET. In this article, an optimized two-gate-two-material tunnel transistor structure is proposed in which the tunneling rate of carriers increased by adding two regions with inherent impurity compared to the common two-gate TFET structures. We simulated the proposed TFET in two dimensions using Silvaco-Atlas software and analyzed its results. The results are as follows: the on-state current (Ion=5.49×10-6A/µm), off current (Ioff=2×10-18A/µm), Subthreshold slope (SS=15.02mV/dec), and the Ion/Ioff =2.74×1012. The calculated results show the improvement of the DC parameters of the device. Manuscript profile -
Open Access Article
13 - The effect of engineering geology on the rock load and squeezing potential in Lot2 of Imamzadeh-Hashem tunnel
Mohammad-Reza Baghban Golpasand Seyyed-Ghafour Alavi Amirhassan Rezaei -
Open Access Article
14 - ارزیابی اثرات زیست محیطی (EIA) انتقال آب بین حوضه ای با استفاده از روش ماتریس ICOLD (مطالعه موردی: تونل کوهرنگ 3)
حسین محمدی احمدمحمودی مهدی رادفر رسول میرعباسی نجف آبادیطرح­های انتقال آب بین­حوضه­ای با روش­های اجرایی معمول مانند خطوط لوله، کانال و احداث تونل انجام می­شوند و بدون شک انتقال آب با روش­ حفر تونل مانند سایر طرحهای عمرانی دارای اثرات و پیامدهای زیست­محیطی فراوانی می­باشد که ضرورت دارد در مراح Moreطرح­های انتقال آب بین­حوضه­ای با روش­های اجرایی معمول مانند خطوط لوله، کانال و احداث تونل انجام می­شوند و بدون شک انتقال آب با روش­ حفر تونل مانند سایر طرحهای عمرانی دارای اثرات و پیامدهای زیست­محیطی فراوانی می­باشد که ضرورت دارد در مراحل مختلف اجرای طرح شامل احداث و بهره­برداری، مورد ارزیابی اثرات زیست­محیطی قرار بگیرند. هدف از این پژوهش ارزیابی اثرات زیست­محیطی (EIA) تونل کوهرنگ 3 در مرحله احداث است. در این پژوهش با استفاده از روش ماتریس ICOLD (کمیسیون بین­المللی سدهای بزرگ جهان) اثرات زیست­محیطی شامل: محیط­های فیزیکی، بیولوژیکی، اقتصادی،-اجتماعی و فرهنگی تونل کوهرنگ 3 بررسی و مطالعه شد. روش ماتریس ICOLD این قابلیت را دارد که با ارزیابی میزان اثرات کیفی زیست­محیطی طرح­ها آنها را به صورت داده­های کمی در چارچوب ماتریس نشان بدهد. تونل سوم کوهرنگ به طول 1/24 کیلومتر به­ منظور انتقال آب به میزان حدود 255 میلیون مترمکعب در سال، جهت تأمین بخشی از نیاز آبی فلات مرکزی ایران در شهرستان کوهرنگ استان چهارمحال ­و بختیاری طراحی و احداث شد. در این پژوهش برای اولین بار اثرات زیست­محیطی فیزیکی، بیولوژیکی، اقتصادی،-اجتماعی و فرهنگی تونل کوهرنگ 3 با استفاده از روش ماتریس آیکولد بررسی و مطالعه شد. یافته­های این پژوهش نشان داد تونل کوهرنگ 3 در مجموع دارای 705 اثر مثبت و منفی است که شامل 244 اثر مثبت و 461 اثر منفی است. سهم آثار مثبت حدود 5/34 درصد و سهم آثار منفی 5/65 درصد می­باشد. تونل کوهرنگ 3 با 627 امتیاز دارای اثرات منفی عمده بر روی محیط­زیست منطقه بوده است. Manuscript profile -
Open Access Article
15 - Investigating the possibility of occurrence of geological hazards in the existing formations at the Hamrov tunnel
Vahid HosseinitoudeshkiKnowledge of geological hazards plays an important role in the selection and installation of timely support system for underground structures. The Hamrov tunnel with an approximate length of 1294 meters in the main way of Sanandaj- Marivan is under construction. B MoreKnowledge of geological hazards plays an important role in the selection and installation of timely support system for underground structures. The Hamrov tunnel with an approximate length of 1294 meters in the main way of Sanandaj- Marivan is under construction. Based on the geo-mechanical conditions of rock masses in the tunnel, it is necessary to investigate the possible geological hazards such as squeezing. In this study, using geological surveys and drilling of boreholes, the way of the tunnel been divided into different units and then the severity of squeezing in each section have been investigated. By comparing the different methods of squeezing evaluation, it was found that the empirical Hoek-Marinos method evaluate the minimum of squeezing and the Jethwa method evaluate the maximum of squeezing for the rock masses of the tunnel. The utmost squeezing potential is related to section of the tunnel where there is the alternation of sandy shale and limestone with shale. According to the survey, the Hamrov tunnel is divided into three sections: A (km 5293 to 5543) with squeezing extreme serious to serious, B (km 5543 to 5973) with squeezing severe to very low, and C (5973 to 6133 km) almost without risk of squeezing. Manuscript profile -
Open Access Article
16 - Prediction of ground settlement induced by mechanized excavation in the Tehran Metro tunnel
Saeed. hosseini Korosh. shahriar Masoud. monjezi MohammadReza. BitarafanThe main issue of tunnelling in urban environment is the prediction of the ground settlements induced by tunnelexcavation, which may cause damage to surface structures. In this paper are used empirical, analytical and threedimensional finite element methods (by ABAQUS p MoreThe main issue of tunnelling in urban environment is the prediction of the ground settlements induced by tunnelexcavation, which may cause damage to surface structures. In this paper are used empirical, analytical and threedimensional finite element methods (by ABAQUS program) for the prediction of ground settlements inducedduring tunnel construction using EPB (earth pressure balance) excavation machine in part of the line 3 of Tehransubway. The results indicate that the three-dimensional FEM predicts a more realistic surface settlement value,and settlement profiles from empirical and analytical methods are narrower than numerical one. Moreover, themaximum predicted settlement by three methods is more than its suggested allowable value. Manuscript profile -
Open Access Article
17 - Comparison of SGR method with the results of analytical equations governing groundwater inflow into Amirkabir tunnel
Hadi Farhadian Meysam Solouki Homayoun KatibehIn this paper, using SGR (Site Groundwater Rating) method, 11 km of Amirkabir tunnel has been studied and categorized into quantitative and qualitative classes from groundwater hazard point of view. Considered parameters in this method are: joint frequency, joint aper MoreIn this paper, using SGR (Site Groundwater Rating) method, 11 km of Amirkabir tunnel has been studied and categorized into quantitative and qualitative classes from groundwater hazard point of view. Considered parameters in this method are: joint frequency, joint aperture, karstification, crashed zone, schistosity, and head of water above tunnel, soil permeability and annual raining. Using SGR method, tunnel site can be categorized into six different classes from no risk to critical. According to this classification more than 60% of Amirkabir tunnel has been located in no risk class and results are compatible with the results of analytical method. Furthermore, approximately 5% of tunnel has been found in critical class that mostly coincides on crashed zones and following analytical method results, inflow rate is 0.46 L/sec/m in this portion of tunnel. Manuscript profile -
Open Access Article
18 - Numerical and Statistical Evaluation of Squeezing Potential of West Kermanshah Tunnel Convey
Vahed Ghiasi ALI GodarihematIn this paper, based on the results of experimental and analytical methods, crushed zone and gurpy rocks masses were identified as the squeezing sections. Then crushed zone and gurpy sections creep parameters at the Bruger model were obtained in the laboratory. Then cru MoreIn this paper, based on the results of experimental and analytical methods, crushed zone and gurpy rocks masses were identified as the squeezing sections. Then crushed zone and gurpy sections creep parameters at the Bruger model were obtained in the laboratory. Then crushed zone and gurpy sections modelling using the software Flac2D with burgers model for 30 days (long-term) were performed. Our numerical modelling results show the large displacements due to very low quality of the rock mass and high overburden in this sections of the tunnel. The results of the numerical modelling in the short-term, that TBM shield would be stuck in this section of tunnel. Also modeling this section in the long-term showed that stability and not seen failure of the segmental support system. But effect squeezing in two sections is not critical. Among the important phenomena that makes problem for tunneling, support and tunnel usage is squeezing which is a type of problems that takes place in weak rocks. Squeezing of the rock is time dependent large convergence, which occurs around the tunnel, and is essentially associated with creep caused by exceeding limiting shear strength. Squeezing is one of the important phenomena in the tunneling industry so drilling in the squeezing cases can be causing serious problems. Predicting the amount of displacement, radial strain, shear strain and plastic zone increment as functions of the squeezing degree resonator factors is one of the basic needs in drilling and tunnel maintenance. Squeezing is behavior that related with weak rock mass deformation and strength properties. This phenomenon is associated with large deformations and time dependent convergence during tunnel excavation. It takes place when a particular combination of induced stresses and material properties pushes some zones around the tunnel beyond the limiting shear stress at which creep starts. Deformation may terminate during construction or continue over a long period of time. West Kermanshah tunnel conveyance (WKTC), with about 8550 meters long and 6.884 m in diameter in the west of Iran is located in Kermanshah province. Mainly parts of the tunnel pass through weak rock make is including types of argillaceous, sandstone and shale, with high 570 meters overburden and will be probably under squeezing condition. Duets in this project the effect of experimental methods, analytical and semi-analytical are evaluated. Then critical section of the squeezing potential presented and finally numerical modelling of this phenomenon is done. Manuscript profile -
Open Access Article
19 - Back analysis of Qazvin – Rasht tunnel using instrumentation data
Kambiz Hedayatnasab Ahmad Adib Kamran Goshtasbi Masoud MonjeziVarious types of numerical analyses such as the finite element method, the boundary element method and thedistinct element method, are used in rock mechanics and in engineering practices for designing rock structuressuch as tunnels, underground caverns, slopes, dam foun MoreVarious types of numerical analyses such as the finite element method, the boundary element method and thedistinct element method, are used in rock mechanics and in engineering practices for designing rock structuressuch as tunnels, underground caverns, slopes, dam foundations and so on. In this paper, the results of backanalysis of Koohin tunnel which is located in the first section of Qazvin – Rasht railway have been presented.The main purpose of this paper is to perform the back analysis of the mentioned!tunnel with the use of numericalmodels. For modeling the tunnel, two different sections are analyzed with Flac 2-D software, which are 30+150and 30+900. To perform back analysis the suitable interval of geomechanical parameters according to the testswhich performed on the core drillings has been determined. With the use of Direct Method in back analysis, theerrors of models have been corrected in several steps and finally the geomechanical parameters of control in30+150 station (Elastic Modules = 0.3 GPa, Cohesion = 0.21 MPa & Internal Angle of Friction = 34°) and in30+900 station (Elastic Modules = 0.3 GPa, Cohesion = 0.21 MPa & Internal Angle of Friction = 35°) have beenachieved. The geomechanical parameters which achieved from back analysis are completely in the choseninterval and compliance with the results of tests which performed on core drillings. On this basis and accordingto the match of the geomechanical parameters which obtained from back analysis with the parameters whichused in designing of the tunnel, the tunnel design and the structure method were confirmed. Manuscript profile -
Open Access Article
20 - Representing a modern method to tunnel stability analysis with introducing a new scheme for Ground Reaction Curve (GRC); case study: Garin dam water Diversion tunnel
S.M Hoseini کاوه Ahangari کامران GoshtasbiThe most important problem in tunneling project about design and performance is selectionsuitable pattern for drilling and support system, in order to stability of rock mass and reductionplasticity zone. Meanwhile determine the amount of tunnel wall deformation prior to MoreThe most important problem in tunneling project about design and performance is selectionsuitable pattern for drilling and support system, in order to stability of rock mass and reductionplasticity zone. Meanwhile determine the amount of tunnel wall deformation prior to supportinstallation is of great importance. When a tunnel is excavated, there is a certain amount ofdeformation, usually 35-45 percent of the fnal tunnel wall deformation, before the support canbe installed. Determining this deformation can be done using either a) observed feld values, orb) numerically from 3D fnite-element models or symmetrical fnite-element models, or c) byuse of empirical relationships such as those proposed by Panet or Vlachopoulos-Diederichs. Inthis paper, convergence-confnement method is applied to tracing ground characteristic curveusing numerical software models and then stress relaxation is exerted to modal that equivalentwith occurred critical convergence until prior to support installation. In this study, a new chartis introduced which unlike conventional charts, the modulus reduction flow has been used inthat vertical axis. Finally the safety factor of support system has been calculated by three different methods. Manuscript profile -
Open Access Article
21 - Environmental Impact of the Accumulation of Tunnel Excavated Soils of Isfahan Subway in Zaynel area (east of Isfahan)
Ali Radhoosh Abdolhosein KangazianThis research has examined the changes that have been made as a result of accumulating the Isfahan subway tunnel excavated soils in the Zeinel area (at the east of Isfahan). The samples of the tunnel fresh excavated soils, of the accumulated soils, and of the natural so MoreThis research has examined the changes that have been made as a result of accumulating the Isfahan subway tunnel excavated soils in the Zeinel area (at the east of Isfahan). The samples of the tunnel fresh excavated soils, of the accumulated soils, and of the natural soils in disposal area were taken, randomly. All the samples were sieved and to determine the percentage of drilling foam material, organic carbon percentage of some of them were analised. Elevation and geographic location of the sampling sites were also determined. the directions and speeds of strong winds that have blown in the east of Isfahan was obtained and ranked. Comparison of the granulometry analysis results of the mentioned soils showed that there are great differences between the mentioned criteria of the freshly excavated soils with natural soils and there are afew diffrences between the mentioned criteria of the accumulated soils with natural soils. These differences increase the permeability in the region and reduce the balance between the morphogenic-pedogenic processes.The topographic findings show that mainly accumulating soils in the region have somehow changed the topography of the area that will cause disruption the balance between the morphogenic and pedogenic processes and increase morphogenic processes. Also, the strong winds don't blow toward Isfahan, consequently the environmental hazards will not be created Manuscript profile -
Open Access Article
22 - Estimation of TBM Utilization with Artificial Neural Networks
Hamid Reza Nejati Morteza AhmadiDetermination of schedule and bid prices for mechanized tunneling needs to estimate of tunneling machine advance rate. Also determination of machine advance rate needs to estimate machine utilization. Although some empirical equations were proposed for this purpose, the MoreDetermination of schedule and bid prices for mechanized tunneling needs to estimate of tunneling machine advance rate. Also determination of machine advance rate needs to estimate machine utilization. Although some empirical equations were proposed for this purpose, these equations don’t have good accuracy. The aim of this study is estimation of TBM utilization with artificial neural networks. For this purpose data set of open TBM tunneling was gathered and a neural network with 5 inputs (in-situ stress, uniaxial compressive strength, disc thrust, joint orientation factor and Q rock mass classification index) and one output (TBM utilization) was designed. Since input parameters have a good relationship with output parameter, neural network estimate TBM utilization with high accuracy. Manuscript profile -
Open Access Article
23 - Numerical modeling of segmental lining of Golab water conveyance tunnel due to reduced environmental impact
mehdi saneiaraei meisam hakimianbidgoli mohamadamin vashadi araeiLack of proper drinking water is a major problem in the Central and Eastern cities of the country. Therefore, the necessity of water transmission projects are posed and since meeting these needs using traditional methods are very difficult, time-consuming and costly; so MoreLack of proper drinking water is a major problem in the Central and Eastern cities of the country. Therefore, the necessity of water transmission projects are posed and since meeting these needs using traditional methods are very difficult, time-consuming and costly; so the mechanized excavation of tunnels and segmental lining are used. The water transferred through the pipes has significant surface destruction. That would result in serious environmental problems. Also, transferring water through the pipes is more expensive than the tunnel. In this paper, after introducing all procedures of segments design, segmental lining of Golab water conveyance tunnel using finite element was modeled. Firstly, loads on segmental lining was determined by UDEC software after installation in tunnel. Then, these amounts of load on the segments used for modeling was applied in ABAQUS software. Results obtained by 3D modeling software showed that the greatest amount of displacement of segments under different stress conditions concerns to the bottom segment. Based on the performed modeling, due to the high compressive stress, the crack is only seen in segment concrete and these results are totally in compliance with Golab tunnel segments observations. Manuscript profile -
Open Access Article
24 - Interaction Effects of Sabzkuh Tunnel Excavation and Ground Water Resources: (Environmental Management Approach)
majid taromi Majid AsadnabizadehIn this paper, hydrogeology and geology of Sabzkuh tunnel path and its environment has been reviewed, so as to anticipation of changes in the natural regime of underground waters and its impacts in springs resources after tunnel excavation with environmental management MoreIn this paper, hydrogeology and geology of Sabzkuh tunnel path and its environment has been reviewed, so as to anticipation of changes in the natural regime of underground waters and its impacts in springs resources after tunnel excavation with environmental management approach has been determined. For this purpose, different formation of tunnel path, faults and their permeability and potential amplitudes were recognized and categorized. From another perspective, water resources and springs of tunnel path were identified and hydrogeological boundary of tunnel path was determined to investigate interactions among tunnel excavation and underground water resources. According to these data, the tunnel path had been divided into two section: 1. High risk areas (Choghakhor region) 2. Low risk areas (Sabzkuh region). After tunnel mechanized excavation, changes of ground and geological complexity of studied zone and influx of mud along with abundance of water into tunnel caused cancelation of tunnel excavation despite all measures carried out for injection and reinforcement in risky area and capabilities of mechanized excavation machine. Following that, due to interaction to fault area of Sakiabad (Aloghareh), this fault had been dried in less than one week. Drying of Sakiabad spring had brought negative effects in terms of social, environmental and economical in the zone. Scrutiny of this factors and considering all parameters, the tunnel excavation had ceased. Reviewing studies and feasibility of all effected sections and with environmental management approach, combination of tunnel in Sabzkuh and water canal in Choghakhor section and change in the profile of path in order to reduce regional environmental impacts have been relatively considered. Manuscript profile -
Open Access Article
25 - Numerical simulation of smoke behavior in fire conditions in a short urban tunnel
Mehdi RafieiAlong with the increasing development of countries, the daily need to transport various goods and equipment and travel in general for many reasons is increasing and for this reason, the number of different types of cars has significantly increased in recent years. In th MoreAlong with the increasing development of countries, the daily need to transport various goods and equipment and travel in general for many reasons is increasing and for this reason, the number of different types of cars has significantly increased in recent years. In this way, this issue has caused heavy traffic on highways and various roads in big cities. Various actions and approaches, including public transportation, have been taken into consideration to facilitate the traffic. However, in some cases the solution to facilitate traffic jams, especially in big cities, is to build urban tunnels. Therefore, in recent years, urban tunnels have been considered as a solution to facilitate traffic. In this regard, the study of safety in tunnels becomes very important. The aim of this article is to simulate a fire in a short tunnel with natural ventilation to consider the behavior of smoke in different scenarios of natural air flow in the tunnel. The results of CFD simulation showed that limited fire (usual small passenger cars) will not cause problems for people as well as rescue team, especially fire extinguishing. Manuscript profile -
Open Access Article
26 - THE ORIGIN AND SPREAD OF QANATS IN THE WORD
shahram ardishirian saleh paregari hossin hatamiSubterranean tunnel-wells (qanat,s) are extremely important in the history of irrigation and human settlement in the arid lands of the Old Word. Apparently originating in pre- Achaemenid Persia, tunnel-wells spread to Egypt, the Levant, and Arabia in Achaemenid ti MoreSubterranean tunnel-wells (qanat,s) are extremely important in the history of irrigation and human settlement in the arid lands of the Old Word. Apparently originating in pre- Achaemenid Persia, tunnel-wells spread to Egypt, the Levant, and Arabia in Achaemenid times (550-331 B.C). The Arabs carried Qanats across North Africa in to Spain and Cyprus; they are also found in central Asia, western China, and on a more limited scale in dry regions of Latin America. In modern times, more than tewenty terms are used to identify these horizontal wells; the Arabic word qanat meaning "lance" or "conduit" is used in iran , the Persian terms "KARIS" is used in Afghanistan, while in Syria, Palestine, and North Africa Fuqard (pronounced foggarra) is the most common term. In all of these regions, tunnel-wells are still being constrcted in the traditional manner, and many sttlements depend on them for irrigation and domestic water. Where used, qanats have stongly influenced village sotio- economic organization and patterns of ownership and tenure. Manuscript profile -
Open Access Article
27 - Numerical Simulation of the Segmental Tunnels Performance in the Swelling Rocks
Arash Jeddi Rouzbeh Dabiri -
Open Access Article
28 - A Parametric Study of Interactions Between Liquefaction Sand Lenses and Shallow Tunnels Under Earthquake Loads
Mohammad Shabani Soltan Moradi Mohammad Azadi Homayoon JahanianIf the saturated sand lenses are placed around the tunnels under the force of the earthquake, liquefaction will occur in them. This will cause settlement of the ground surface and changes in forces and anchors on the tunnel lining. For this purpose, it is important to e MoreIf the saturated sand lenses are placed around the tunnels under the force of the earthquake, liquefaction will occur in them. This will cause settlement of the ground surface and changes in forces and anchors on the tunnel lining. For this purpose, it is important to evaluate the change of different parameters of the sand lens and the change of the thickness of the tunnel lining in the part of the sand lens and the changes in the diameter and depth of the tunnel as well as the location of the sand lens considering the tunnel inside it. Therefore, this article investigates the mentioned changes in shallow tunnels in the location of sand lens in flowing soils surrounded by clay. In this article, FLAC 3D software is used to determine changes in pore water pressure and effective stress reduction after sand lens liquefaction. Based on the obtained results, if the sand lenses are placed at a depth of less than 10 meters, they increase the land surface subsidence by 36% compared to the reference model B, with an increase of 2 meters in the depth of the sand lens compared to the reference model B, the value of the maximum bending anchor and axial force on the tunnel lining increases by 35.7% and 14.4%, respectively, in the sand lens part. The findings of the present study can be very useful in the decision-making process of tunnels that are dug inside flowing sand lenses. Manuscript profile -
Open Access Article
29 - Assessment of Soil cohesion of Soils on Tunnel Excavation
Mohammad Azadi -
Open Access Article
30 - Soil-Interaction of Intake Pressure Tunnels under Ground Strength Reduction Conditions due to Cracking of the Lining (Case study: Dasht-e-Abbas intake pressure tunnel)
seysd majddin Mir Mohammad Hosseini P Malek Mohammadib M. Asadolahi Pajouhc -
Open Access Article
31 - The Stability Assessment of Dasht-e-Abbas Pressure Intake Tunnel Subjected to Ground Strength Reduction-Iran
S. M Mir Mohammad Hosseini P Malek Mohammadi M Kargar -
Open Access Article
32 - Assessment of the Drain Conditions on Variations of the Pore Pressure in Surrounding Soil of the Tunnel
Mohammad Azadi Azadi S.M Mir Mohammad Hosseinib S.M. Nasimifar M Pouranian -
Open Access Article
33 - Analysis of support pressure for stabilization of rock blocks in the Zaker tunnel
Vahid Hosseini Toudeshki -
Open Access Article
34 - The Effects of Shallow Tunnels on Nearby Structures
Mohammad Azadi A. Zahedi -
Open Access Article
35 - Evaluation of Effective Parameters on the Underground Tunnel Stability Using BEM
M Panji J Asgari Marnani Sh Tavousi Tafreshi -
Open Access Article
36 - Analysis of Circular Reinforced Tunnels by Analytical Approach
Ahmad Fahimifar Masoud Ranjbarnia -
Open Access Article
37 - An innovative method for estimating optimal Gate work function and dielectric constant of a nanoscale DG-TFET based on analytical modeling of tunneling length in ambipolar Off and ON states
Fayzollah Khorramrouz Seyed Ali Sedigh Ziabari Ali Heydari -
Open Access Article
38 - An innovative method for estimating optimal Gate work function and dielectric constant of a nanoscale DG-TFET based on analytical modeling of tunneling length in ambipolar, Off and ON states
Fayzollah Khorramrouz Seyed Ali Sedigh Ziabari Ali Heydari -
Open Access Article
39 - A Review of Single Electron Transistors
Yaghoob Mohammadmoradi Nader Javadifar Atila Skandarnezhad -
Open Access Article
40 - Designing and Manufacturing the Multiple Jets Simulator and Experimental Investigation of the Multiple Jets in Crossflow
Saeed Toolani Mohamad Hojaji -
Open Access Article
41 - 3-D Numerical Investigation of Flow Field in Starting Stage of High Speed Wind Tunnels
Mehdi Jahngiri -
Open Access Article
42 - Design and Manufacturing of Jet to free Stream Simulator to Experimental Study of Interaction of Oblique Jet in Crossflow
Moslem Ahmadi Mohamad Hojaji Saeed Toolani -
Open Access Article
43 - High-Performance Spintronic Based-Neuromorphic Computing System Enabled by Current Monitoring Peripheral Circuit
Pegah Shafaghi Hooman Farkhani Mehdi Dolatshahi Homayoun Mahdavi-NasabImplementation of neuromorphic computing systems (NCSs) using digital and analog circuits occup­ies a high chip area and consumes high power. With the advancement of nanotechnology, the hybrid Magnetic tunnel junction/Complementary metal–oxide–semiconduc MoreImplementation of neuromorphic computing systems (NCSs) using digital and analog circuits occup­ies a high chip area and consumes high power. With the advancement of nanotechnology, the hybrid Magnetic tunnel junction/Complementary metal–oxide–semiconductor (MTJ/CMOS) circuits have made it possible to implement NCSs with higher density and lower power consumption. However, still there is a gap between the performance of the human brain and NCSs. To mitigate this gap, it is essential to further decrease the energy consumption and the delay of the NCS. The high energy consumption of the MTJ-based NCS is mostly related to the high current needed to switch the MTJ state. Hence, some previous methods tried to perform real-time tracking of the MTJ state by monitoring its voltage and cutting off its current immediately after switching. However, due to the small voltage changes after switching, these methods suffer from a high-power consumption (they need power-hungry amplifiers). In this paper, a new method based on the tracking of MTJ current (instead of voltage) and terminating the MTJ current after switching is proposed. Due to the large changes in the MTJ current after switching (about 40%), there is no need to use an amplifier in the proposed circuit. Therefore, the conventional voltage-mode sensing circuit is replaced with the proposed circuit, to improve the energy efficiency, speed and delay of the NCS. In all state-of-the-art designs, the voltage changes on nodes across the MTJ (PL, FL or both of them) have been used to detect the MTJ switching. However, the proposed circuit detects the MTJ switching by properly sensing the MTJ current and terminates its current immediately. The simulation results in 65-nm CMOS technology confirm that the proposed technique improves the energy consumption and speed of the NCS by 49% and 2.1X compared with the typical NCS. Manuscript profile -
Open Access Article
44 - Time variation of dust concentration due to wind blowing using wind tunnel
ABDOLAZIM GHOMEISHI Mehdi Ghomeshi MOHAMMAD MAHMOODIAN SHOOSHTARI AHMAD LANDI Mohammad hossein purmohammadiDust is created by wind erosion. In nature, based on the size of the particles, the movement of soil particles due to wind is carried out in three ways. Rolling, jumping and suspension. In the wind ranges that usually occur in nature, proportional to the diameter of the MoreDust is created by wind erosion. In nature, based on the size of the particles, the movement of soil particles due to wind is carried out in three ways. Rolling, jumping and suspension. In the wind ranges that usually occur in nature, proportional to the diameter of the soil particles, these three modes of particle motion are somewhat separable. Particles smaller than 0.1 mm in diameter are usually suspended, soil particles with a diameter of 0.05 to 0.5 mm usually bounce, and soil particles with a diameter of 0.5 to 2 mm move in a crawling (rolling) manner. In the wind tunnel tests, which were conducted on the soil samples collected from the dust centers in the southeast of Ahvaz. It showed that at the reference point, when the wind blows, a lot of dust is formed in front of the soil mass.The obtained results show that the maximum amount of dust is formed in the first 150 seconds. The maximum amount of dust produced occurs in the first 85 seconds, which is about 7 times more than the dust after the first 150 seconds. Manuscript profile -
Open Access Article
45 - Geotechnical-Geological studies and tunnel support design at Rudbar-Lorestan dam site, Iran
Saeed Masoud Shamsoddin Parviz Maarefvandz -
Open Access Article
46 - پیش بینی نرخ نفوذ ماشین حفر تونل تمام مقطع با استفاده از ترکیب شبکه های عصبی مصنوعی و روش مونت کارلو
سید مصلح افتخاری محمد مختاریان علیرضا باغبانان -
Open Access Article
47 - Estimating of seismicity parameters in Golab 2 conveyance water tunnel with preliminary Gutenberg - Richter Method
Mohammad Azarafza Shahrzad Nikoobakht Ebrahim Asghari-Kaljahi Mirali-Akbar Nogol Sadat -
Open Access Article
48 - Modeling, stress distribution and the change of ground behavior during excavation of Tehran city underground tunnel
Naser Ebadati Mojtaba Kaboli -
Open Access Article
49 - Machine Foundations on Fiber Concrete Tunnel in Reinforced Sand
Alireza Hajiani Boushehrian -
Open Access Article
50 - PGA Estimation for Gulab 2 Water Transfer Tunnel using Probabilistic Seismic Hazard Analysis Method (PSHA)
Javad Salamati Maryam Haghbeen Seyed Mohammadali Sadreddini -
Open Access Article
51 - Numerical investigation of settlement effect caused by tunneling on surface structures based on pile group
Alireza Darvishpour Asadollah Ranjbar Karkanaki Hossein Meshki Mohsen Parviz -
Open Access Article
52 - Evaluating the Effect of Fiber Addition on Seismic Performance of Segmental Tunnel Lining
Saeed Farokhi Zadeh majid moradi Ata Hojatkashani -
Open Access Article
53 - Numerical Evaluating of effective and behavior of balancing reservoir of water hummer on water tunnels lining to turbine in concrete dams
H.R Vosoughifar A.R Daneshkhah -
Open Access Article
54 - Performance Analysis of InAs/AlGaSb Heterojunction Electron-Hole Bilayer Tunnel Field Effect Transistor for Low-Power High-Speed Digital Computing
Zahra AhangariIn this paper, a novel device, namely heterojunction electron-hole bilayer tunnel field effect transistor (HJ-EHBTFET), is proposed which outperforms conventional tunnel field effect transistor (TFET) in terms of electrical performance. The use of lattice matched InAs/A MoreIn this paper, a novel device, namely heterojunction electron-hole bilayer tunnel field effect transistor (HJ-EHBTFET), is proposed which outperforms conventional tunnel field effect transistor (TFET) in terms of electrical performance. The use of lattice matched InAs/Al0.6Ga0.4Sb material combination results in a broken band gap configuration, making it highly suitable for high speed ultra-low applications, as it requires smaller gate bias for the onset of tunneling. The impact of critical design parameters on the device performance is comprehensively investigated. The proposed device utilizes electrical doping instead of physical doping for the creation of tunneling junction, which effectively addresses the problem of low solubility of dopants in heavily doped III-V materials. The top gate and bottom gate workfunction are critical design parameters that effectively modulated the electrically induced charges at the tunneling junction and consequently, affect the tunneling rate. In order to obtain the lowest possible transition voltage for the onset of tunneling, a variation matrix of threshold voltage variation is computed as a function of gate electrode workfunction. Through this process, a step-like behavior from off-state to on-state has been achieved, with a subthreshold swing of 3 mV/dec and on/off current ratio of 5.8×1012, thereby paving the way for the design of low-power high-speed digital computing systems. Manuscript profile -
Open Access Article
55 - Relationship between financial strategies and corporate governance on the behavior of stockholders' tunnels on the performance of companies admitted to the Tehran Stock Exchange
Alireza Amirkabiri Hossein Gharehbiglo behjat abcharThe next financial strategy is the strategy of the company that determines the nature and direction of the organization's finances. The ultimate goal of each trading company is to increase the shareholder's wealth, and desirable performance will increase the value of th MoreThe next financial strategy is the strategy of the company that determines the nature and direction of the organization's finances. The ultimate goal of each trading company is to increase the shareholder's wealth, and desirable performance will increase the value of the company and ultimately increase the shareholder's wealth. Companies can not achieve their goals without having the right strategy, and strategy development results from the evaluation of performance from a variety of dimensions. The dimensions of corporate governance (adequacy and ability) are a set of internal and external control mechanisms that establish the right balance between equity on the one hand and the needs and authority of the board of directors on the other. The results-based research, A development based on purpose, descriptive-explanatory and method-based, is therefore an event. The statistical population of this research is pharmaceutical companies accepted in Tehran Stock Exchange which 25 companies were selected by judgment method. The data gathering tool is an analysis of audited financial statements of corporations, and T, Loonce, Kolmogroft-Smirnov and Uonom-Whitney tests, Chow and Hausman tests and regression models have been used. The results show that there is a higher and more significant difference between tuneal behavior of stockholders on firm performance (average return on equity, return on equity, Qobin ratio, and margin of profit) with a coherent financial strategy with corporate governance. Manuscript profile -
Open Access Article
56 - Evaluation of associated factors with carpal tunnel syndrome in patients referred to orthopedic and neurosurgery clinic of Azad Islamic universities hospitals
Khosro Shayan Marziyeh GhanadIntroduction: Carpal tunnel syndrome (CTS), an entrapment of the median nerve at the wrist, is the most commonly encountered neuropathy causing disability. The aim of this study is to compare age, gender, high body mass index (BMI), wrist circumference, occupation, comp MoreIntroduction: Carpal tunnel syndrome (CTS), an entrapment of the median nerve at the wrist, is the most commonly encountered neuropathy causing disability. The aim of this study is to compare age, gender, high body mass index (BMI), wrist circumference, occupation, computer use, and other systemic factors in CTS patients with controls. Methods: We performed a case–control study with 100 CTS and cases 100 controls In a six months period during 2014. Patients were selected from those referred to nerve conduction studies and electromyography in university hospitals of Islamic Azad Universty of Mashhad. Patients were excluded if they had a history of cigarette smoking, addiction, alcohol, diabetes mellitus, or other known systemic diseases such as hypertension, amyloidosis or rheumatoid arthritis. Age, sex, occupation, history of trauma to the wrist and forearm, pregnancy, wrist circumference, and computer work were asked by one researcher in all cases and study groups. Data were analysed by SPSS ver, 18 by Chi-square test or T-test. Result: The mean age was greater in the case group than in the control (49.8+15.1 ver 37.0+14.5 years, P=0.0001). The mean BMI was 29.0+4.2 kg/m2 in case group whereas it was 23.2+2.8 kg/m2 in the case group (P=0.00001). There was no significant differece between two groups in terms of gender (P=0.202). 66.7% of retirees and 57.4% of housewives had carpal tunnel syndrom. Analysis showed wrist circumference was higher in case group (16.8+1.3 cm ver 16.4+1.4, P=0.036) and also patients had more steroid usage (P=0.004), but history of trauma to the wrist and forearm was not significantly associated with CTS. Conclusions: Our study confirms thatobesity, age and wrist circumference, steroid usage, and occupation have more incidence in CTS in comparision to the normal population. Manuscript profile -
Open Access Article
57 - Optimization of surficial settlement originated from the excavation of twin tunnels on surface structures with finite dimensions
Hesam Pourhabiby MasulehIn urban regions, the stability and safety of surface structures are essential. With the development of cities and increasing building density in metropolitan areas, the construction of underground structures like subway tunnels will be considered more and more. The tun MoreIn urban regions, the stability and safety of surface structures are essential. With the development of cities and increasing building density in metropolitan areas, the construction of underground structures like subway tunnels will be considered more and more. The tunnels are located close to the ground surface in most urban regions. Therefore, excavating these tunnels causes some displacements in the soils around the tunnels, leading to some adverse effects on the surface structures. Predicting deformations looks essential to reducing these effects, showing the importance of tunnel and structure interaction. In this paper, using three-dimensional numerical simulation and parametric studies, the effect of various parameters on the displacement of tunnels and their adjacent buildings are studied. The optimum surface settlement values are predicted using the neural network and developed optimization algorithms. The parameters under study are composed of: the horizontal distance between tunnels, the depth of tunnels, the angle between tunnels, the excavation distance between two tunnels, the diameter of the tunnels, tunnels' contraction, the soil's internal friction angle, and the soil's cohesion. Using a neural network and optimization algorithms can considerably help optimize the design and significantly reduce adverse effects on the surface structures during the tunnel excavation. The results from the neural network showed that the optimum state of displacement happens when the soil's cohesion, tunnels' contraction, diameter, and depth are the minimum values, and the excavation distance between two tunnels is the maximum value. Manuscript profile
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