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Sino-US English Teaching 2010年第7期7卷 1-8页

作者： Nasser.rashidi Fatimah Farhani Department of Foreign Languages and Linguistics College of Literature and Humanities Shiraz University Shiraz *** Iran

This study was an attempt to examine the relationship between Iranian EFL （English as Foreign Language） learners＇ depth of vocabulary knowledge and their lexical inferencing strategy use and success. The participants in this study were 32 intermediate senior students of Shiraz Azad University majoring in English translation. The Word Associates Test （WAT）（read, 1993） was used to measure their depth of vocabulary knowledge and lexical inferencing strategy questionnaire which was part of Schmitt （1997）, vocabulary learning strategies as well as a reading passage （Haastrup, 1999）, cited in Nassaji （2004）, were used to determine their lexical inferencing strategy use and success. results indicate that：（1） Those who have stronger depth of vocabulary knowledge use certain strategies more frequently than those who have weaker depth of vocabulary knowledge; （2） The students with stronger depth of vocabulary knowledge make more effective use of certain types of lexical inferencing strategies. These findings support the importance of depth dimension of vocabulary knowledge and the role it plays in guessing the meaning of unknown words.

关键词： depth vocabulary knowledge breadth lexical inferencing strategies

A Methodology for Bridge Condition Evaluation

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Journal of Civil Engineering and Architecture 2012年第9期6卷 1149-1157页

作者： Maria rashidi Peter Gibson Faculty of Engineering University of Wollongong NSW 2522 Australia

Due to the substantial role of bridges in transportation networks and in accordance with the limited funding for bridge management, remediation strategies have to be prioritised. A conservative bridge assessment will result in unnecessary actions, such as costly bridge strengthening or repairs. On the other hand, any bridge maintenance negligence and delayed actions may lead to heavy future costs or degraded assets. The accuracy of decisions developed by any manager or bridge engineer relies on the accuracy of the bridge condition assessment which emanates from visual inspection. Many bridge rating systems are based on a very subjective procedure and are associated with uncertainty and personal bias. The developing condition rating method described herein is an important step in adding more holism and objectivity to the current approaches. Structural importance and material vulnerability are the two main factors that should be considered in the evaluation of element structural index and the causal factor as the representative of age, environment, road class and inspection is implemented as a coefficient to the OSCI （overall structural condition index）. The AHP （analytical hierarchy process） has been applied to evaluate the priority vector of the causal parameters.

关键词： Bridge inspection condition assessment structural importance material vulnerability causal factor AHP OSCI.

Elevated Ferrite Film Circulator with Different Permittivities for Layers: An Analytical Expression for the Input Conductance Employing Perturbation Method

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Journal of Electromagnetic Analysis and Applications 2010年第9期2卷 529-542页

作者： Arash rashidi Ali Banai 不详

The main idea of this paper is to find an analytical formula for the input conductance of an elevated ferrite film circu-lator to match it systematically to the desired matching network. For solving the ferrite loaded dielectric resonator included in stripline elevated ferrite film circulator, the off diagonal components of the permeability tensor are taken as the perturbation. The electromagnetic fields computations are done for unperturbed structure. The dipolar resonant frequencies corresponding to harmonics of the resonant modes are then calculated using the perturbation integrals. The quality factor of the circulator is derived in terms of these dipolar resonant frequencies. Energy integrals are calculated to find the energy stored in the ferrite and dielectic layers. An analytical expression for the input conductance of the elevated ferrite film circulators is derived by using the quality factor and energy integrals. In this expression the ferrite and dielectric layers can have different permittivities. Some discussions about the effect of ferrite film thickness and permittivity mismatch on the bandwidth of the circulator are investigated by HFSS commercial software.

关键词： Elevated Ferrite Circulator Perturbation Integral Splitting Factor Dipolar resonant Frequencies

Drinking plain water is associated with decreased risk of depression and anxiety in adults:results from a large cross-sectional study

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World Journal of Psychiatry 2018年第3期8卷 88-96页

作者： Fahimeh Haghighatdoost Awat Feizi Ahmad Esmaillzadeh Nafiseh rashidi-Pourfard Ammar Hassanzadeh Keshteli Hamid roohafza Payman Adibi Food Security research Center Isfahan University of Medical Sciences Department of Community Nutrition School of Nutrition and Food ScienceIsfahan University of Medical Sciences Biostatistics and Epidemiology Department School of Health and Psychosomatic Research CenterIsfahan University of Medical Sciences Psychosomatic research Center Isfahan University of Medical Sciences Department of Community Nutrition School of Nutritional Sciences and DieteticsTehran University of Medical Sciences Shahid Motahari Hospital Department of Medicine University of Alberta Integrative Functional Gastroenterology research Center Isfahan University of Medical Sciences Gastroenterology Section Department of Internal MedicineIsfahan University of Medical Sciences

AIM To investigate the relation between plain water drinking and risk of depression and anxiety among a large sample of Iranian *** A total of 3327 Iranian general adults were included in this cross-sectional study. Validated Iranian version of the Hospital Anxiety and Depression Scale was used to assess anxiety and depression. Water consumption was assessed by asking about the number of glasses of water that consumed daily. Water consumption was categorized into r/*** In the crude model, the lowest level of water drinking(red with reference group(≥ 5 glasses/d) doubled the risk of depression and anxiety(P r adjusting potential confounders, this inverse link remained significant for depression(Or: 1.79; 95%CI: 1.32, 2.42; P r anxiety(Or: 1.49; 95%CI: 0.98, 2.25; P = 0.109). In stratified analyses by sex, after controlling for potential confounders, water drinking rement in the risk of depression in men and women, respectively(P rved for anxiety either in men or in *** We found inverse associations between plain water consumption and depression. Also, these findings showed a tended risky association, but not statistically significant, between lower levels of water consumption and anxiety. These findings warrant evaluation in prospective and clinical trials studies to establish the plausible role of water in mental health status.

关键词： Water Anxiety Depression Psychological disorders Iranian

Solution of analytical model for fuel spray penetration via homotopy perturbation method

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Propulsion and Power research 2016年第3期5卷 202-210页

作者： B.Jalilpour S.Jafarmadar D.D.Ganji M.M.rashidi Department of Mechanical Engineering Faculty of EngineeringUrmia UniversityUrmiaWest Azerbaijan 57561-15311Iran Babol University of Technology Department of Mechanical EngineeringP.O.Box 484BabolIran Shanghai Key Lab of Vehicle Aerodynamics and Vehicle Thermal Management Systems Tongji UniversityShanghai 201804China ENN-Tongji Clean Energy Institute of Advanced Studies ShanghaiChina

The present paper attempts to solve equations in the initial stage and the two-phase flow regime of fuel spray penetration using the HPM-Padétechnique,which is a combination of the homotopy perturbation method(HPM)and Padé*** the initial stage,the effects of the droplet drag and the air entrainment were explained while in the two-phase flow stage,the spray droplets had the same velocities as the entrained *** results for various injection pressures and ambient densities are presented graphically and then discussed *** obtained results for these two stages show a good agreement with previously obtained expressions via successive approximations in the available *** numerical result indicates that the proposed method is straight forward to implement,efficient and accurate for solving nonlinear equations of fuel spray.

关键词： Spray Air entrainment Initial stage Two-phase flow Homotopy perturbation method(HPM)

Antioxidant effects of quercetin in freeze-thawing process of mouse spermatogonialstem cells

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Asian pacific Journal of reproduction 2019年第1期8卷 7-12页

作者： Fardin Amidi Zahra rashidi Zahra Khosravizadeh Kajal Khodamoradi Ali Talebi Shadan Navid Mehdi Abbasi Department of Anatomy School of MedicineTehran University of Medical SciencesTehranIran

Objective: To evaluate the antioxidant effect of quercetin on cell viability, reactive oxygen species (rOS) contents and apoptosis of cryopreserved mouse spermatogonial stem cells (mSSCs). Methods: mSSCs were isolated from neonate mice and cultivated in culture medium containing 30 μM quercetin for 48 h and then frozen for 2 weeks. After thawing, MTT assay was carried out to analyze the cell viability. Moreover, intracellular rOS levels were measured by flow cytometery and apoptosis was evaluated by detection of phosphatidylserine externalization assay and also real-time polymerase chain reaction. results: Pre-treatment of mSSCs by 30 μM quercetin significantly decreased intracellular rOS content and apoptotic cell numbers and improved viability of mSSCs. Moreover, the gene expression of Bcl-2 and Bax significantly increased and decreased respectively after the freeze-thawing process. Conclusions: Pre-treatment of mSSCs with quercetin can improve cell viability and reduce apoptosis during freeze-thawing process. It can be a promising way to improve the quality and efficiency of cryopreservation protocols used in fertility preservation strategies.

关键词： Spermatogonial stem cell Cryopreservation Oxidative stress Quercetin

Mathematical Modeling of Onset of Convection in a Porous Layer with Viscosity Variation

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Journal of Thermal Science 2000年第2期9卷 141-145页

作者： Fariborz rashidi Ali Bahrami Chemical Engineering Department, Amirkabir University of Technology, 424 Hafez Ave., Tehran, IrAN Chemical Engineering Department Amirkabir University of Technology Tehran Iran

Instability theory is applied to diffusion-convection phenomenon in porous media, where the area in direction of transfer is large and viscosity of the oil varies due to gas dissolution. An important application of this theory arises where diffusion-convection is employed as an EOr technique in oil reservoirs. As a bed of gas is formed below a colunm of oil, gas starts to diffuse into the oil. Therefore, the oil becomes lighter and an inverse gradient of density is developed as more gas diffuses in. Although this inverse density gradient is potentially unstable, convection will not initiate until the gradient extends to a certain value. The condition at which convection begins is known as "the onset of convectin" and is well specified by the dimensionless rayleigh number. In this study, an instability analysis is made for convection-diffusion in large porous media. Unlike Other studies where viscosity is assumed constant in this work viscosity is postulated to be a function of gas concentration. It is shown that the mathematical model developed reduces to previous models if the viscosity vacations are ignored.

关键词： instability theory flat porous media rayleigh number onset of convection viscosity variations.

An advanced turbulator with blades and semi-conical section for heat transfer improvement in a helical double tube heat exchanger

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Journal of Central South University 2021年第11期28卷 3491-3506页

作者： Seyed Hossein HASHEMI KArOUEI Seyed Soheil MOUSAVI AJArOSTAGHI Saman rashidi Elham HOSSEINIrAD Department of Mechanical Engineering Babol Noshirvani University of TechnologyBabolMazandaranIran Department of Energy Faculty of New Science and TechnologiesSemnan UniversitySemnanIran Department of Chemical Petroleumand Gas EngineeringSemnan UniversitySemnanIran

In present work,a helical double tube heat exchanger is proposed in which an advanced turbulator with blades,semi-conical part,and two holes is inserted in inner *** geometrical parameters,including angle of turbulator’s blades(θ) and number of turbulator’s blades(N),are *** indicated that firstly,the best thermal stratification is achieved at θ=180°.Furthermore,at the lowest studied mass flow rate(m = 8 × 10^(-3) kg/s),heat transfer coefficient of turbulator with blade angle of 180° is 130.77%,25%,and 36.36% higher than cases including without turbulator,with turbulator with blade angle of θ =240°,and θ =360°,***,case with N=12 showed the highest overall *** the highest studied mass flow rate(m = 5.842 × 10^(-2) kg/s),heat transfer coefficient for case with N=12 is up to 54.76%,27.45%,and 6.56% higher than cases including without turbulator,with turbulator with N=6,and with turbulator with N=9,respectively.

关键词： helical double tube heat exchanger turbulator blade thermal performance swirl flows

A numerical study for off-centered stagnation flow towards a rotating disc

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Propulsion and Power research 2015年第3期4卷 169-178页

作者： M.Heydari G.B.Loghmani M.M.rashidi S.M.Hosseini Department of Mathematics Yazd UniversityP.O.Box 89195-741YazdIran Mechanical Engineering Department Engineering Faculty of Bu-Ali Sina UniversityHamedanIran Department of Mathematics Khatam CenterIslamic Azad UniversityYazdIran

In this investigation,a semi-numerical method based on Bernstein polynomials for solving off-centered stagnation flow towards a rotating disc is *** method expands the desired solutions in terms of a set of Bernstein polynomials over a closed interval and then makes use of the tau method to determine the expansion coefficients to construct approximate *** method can satisfy boundary conditions at *** properties of Bernstein polynomials are presented and are utilized to reduce the solution of governing nonlinear equations and their associated boundary conditions to the solution of algebraic *** results are presented to investigate the influence of the rotation ratioαon the radial velocity,azimuthal velocity and the induced velocities.A comparative study with the previous results of viscous fluid flow in the literature is made.

关键词： Off-centered stagnation flow Similarity transform Bernstein polynomials Function approximation Tau method

Using UPFC and IPFC Devices Located by a Hybrid Meta-Heuristic Approach to Congestion relief

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Energy and Power Engineering 2013年第7期5卷 474-480页

作者： Hamid Iranmanesh Masoud rashidi-Nejad Islamic Azad University Jiroft Branch Jiroft Iran

This paper proposes new methodology for the placement of FACTS devices in transmission systems to reduce congestion. Congestion management comprises congestion relief and congestion cost. The traditional approach to remedying congestion lies in reinforcing the system with additional transmission capacity. Although still feasible, this approach is becoming more and more complex and it is often challenged by the public [1]. Congestion relief can be handled by using FACTS devices, where transmission capability may be improved. Congestion relief using FACTS devices requires a two step approach: first, the optimal location of these devices in the network and then, the settings of their control parameters. UPFC and IPFC have full dynamic control on the transmission parameters, voltage, line impedance and phase angle. real Genetic Algorithm (rGA) optimization technique is used to solve this congestion relief problem while analytical hierarchy process (AHP) with fuzzy sets is implemented to evaluate rGA fitness function. The results are obtained for modified IEEE 5 bus Test System.

关键词： Congestion relief rGA AHP Fuzzy Sets UPFC IPFC