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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1033-1044页

作者： A.g.ARANI g.s.jafari Faculty of Mechanical Engineering University of Kashan Institute of Nanoscience & Nanotechnology University of Kashan

The nonlocal nonlinear vibration analysis of embedded laminated micro- plates resting on an elastic matrix as an orthotropic Pasternak medium is investigated. The small size effects of micro/nano-plate are considered based on the Eringen nonlocal theory. Based on the orthotropic Mindlin plate theory along with the von Kármán geo- metric nonlinearity and Hamilton＇s principle, the governing equations are derived. The differential quadrature method （DQM） is applied for obtaining the nonlinear frequency of system. The effects of different parameters such as nonlocal parameters, elastic me- dia, aspect ratios, and boundary conditions are considered on the nonlinear vibration of the micro-plate. Results show that considering elastic medium increases the nonlinear frequency of system. F^lrthermore, the effect of boundary conditions becomes lower at higher nonlocal parameters.

关键词： nonlinear vibration laminated micro-plate orthotropic Pasternak medium,differential quadrature method

Theoretical framework of the Isfahani style: Inspiring sustainable aspects of a vernacular urban development

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Frontiers of Architectural Research 2024年第2期13卷 349-369页

作者： Hatef jafari sharami seyed Jamalaldin Hosseini Department of Architecture and Urbanism University of EyvanekeyEyvanekey 99888-35918Iran Faculty of Civil and Architecture University of EyvanekeyEyvanekey 99888-35918Iran

The Isfahani style represents a method of traditional Iranian architecture and urban development that existed in the early 20th century and is regarded as a leading model in most traditional Iranian cities. It exhibits several vigorous features contributing to its recognition as a traditional approach to sustainable architecture and urban development. This research endeavors to reveal a theoretical framework beneath these inspiring aspects using the typology of sustainable modern forms, including the hierarchy, passive design strategies, compactness, density, diversity, mixed land use, pluralism, balance, good composition, and integration over time. To this end, the study employs qualitative research methods, drawing from traditional samples, to identify innovative, energy and socially efficient, and low-impact strategies implemented in this vernacular architecture of Iran's semi-arid and hot climates. The findings revealed that the neighborhood concept as a local and plural community (Mahalla) was a vital phenomenon in Iran's urban development. Apparently, the demise of this paradigm effectively played an important role in the numerous challenges regarding the social, energy, and economic viability of modern Iranian cities. Hence, this study presented theoretical frameworks—aligned with sustainable concepts—from the Isfahani style through its analysis, classification, and interpretation, which can contribute to modern urban development.

关键词： Isfahani style Vernacular urban development sustainable urban development Iranian cities Vernacular architecture

Nurses'attitude toward patients'safety climate during COVID-19 pandemic:a cross-sectional study

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Frontiers of Nursing 2024年第1期11卷 39-46页

作者： Asra Nassehi Kobra ghorbanzadeh somaye Moayedi Javad jafari Parvin Mahmoodi Mojtaba jafari Department of Nursing Bam University of Medical SciencesBamIran Department of Nursing Khalkhal University of Medical SciencesKhalkhalIran Community Nursing Research Center Department of NursingZahedan University of Medical SciencesZahedanIran Clinical Care Research Center Department of NursingNursing and Midwifery SchoolKurdistan University of Medical SciencesSanandajIran

Objective:Patient safety is a fundamental factor in improving the quality of care provided in ***,it is considered a significant parameter by all healthcare organizations around the *** present study was conducted to investigate the attitude of nurses toward the patient safety climate during the Coronavirus Disease 2019(COVID-19)pandemic in the southeast of ***:This is a cross-sectional descriptive *** all the nurses working in one of the hospitals in the southeast of Iran,171 nurses participated in the study through convenience sampling *** survey was conducted between June 1 and July 30,2020.A 2-part questionnaire including demographic information and an assessment of nurses'attitudes toward patients'safety climate was used for data collection in *** content validity of the scale is(0.77)and reliability was re-calculated and confirmed by the present study with Cronbach's alpha(α=0.9).Data were analyzed by sPss 20(IBM Corporation,Armonk,New York,United states)using descriptive and analytical statistical ***:The mean score of safety climates was 3.2±5.20(out of 5 scores).The results showed that among all dimensions of the safety climate,only the education dimension was statistically significant between males and females(Pso,there was a significant relationship between the overall average of the safety climate and its dimensions according to the people's position only in the dimension of supervisors'attitude(Psignificant correlation between the education level and the overall score of safety climate(Ps well as the supervisor's attitude dimension(Ps ***:The results showed that the safety climate was at a relatively favorable *** the impact of nurses'attitudes on the safety climate of patients,its improvement seems *** is recommended to design training courses and educate nurses in order to promote a p

关键词： COVID-19 Iran nurses patient safety climate

Late infection after peri-orbital autologous micro-fat graft:a case presentation and literature review

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 603-606页

作者： Farzad Pakdel Hassan Asadigandomani Melika Arab Bafrani Zohreh Nozarian Zohre Abedinifar Niloofar Pirmarzdashti Behzad jafari Zaynab siami Department of Oculofacial Plastic surgery Farabi HospitalSchool of MedicineTehran University of Medical SciencesTehran ***Iran Craniomaxillofacial Research Center Tehran University of Medical SciencesTehran ***Iran Department of Ophthalmology School of MedicineTehran University of Medical SciencesTehran ***Iran Department of Pathology Farabi HospitalSchool of MedicineTehran University of Medical SciencesTehran ***Iran Department of Microbiology Farabi HospitalSchool of MedicineTehran University of Medical SciencesTehran ***Iran Pediatric Cell and gene Therapy Research Center Children’s Medical CenterSchool of MedicineTehran University of Medical SciencesTehran ***Iran

Citation:Pakdel F,Asadigandomani H,Arab Bafrani M,Nozarian Z,Abedinifar Z,Pirmarzdashti N,jafari B,siami *** infection after peri-orbital autologous micro-fat graft:a case presentation and literature *** J Ophthalmol ... 详细信息

关键词： graft orbital after

Correction:Integration of light and hormone signaling pathways in the regulation of plant shade avoidance syndrome

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aBIOTECH 2024年第1期5卷 115-115页

作者： Yang Liu Fereshteh jafari Haiyang Wang Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China state Key Laboratory for Conservation and Utilization of subtropical Agro-Bioresources South China Agricultural UniversityGuangzhou 510642China guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China

Correction:aBI0TECH(2021)2:131-145 https://doi.0rg/10.1007/s42994-021-00038-1 In this article the author's name Fereshteh jafari was incorrectly written as Feresheeh *** original article has been *** Access This article is licensed under a Creative Commons Attribution 4.0 International License,which permits use,sharing,adaptation,distribution and reproduction in any medium or format.

关键词： Integration Open Creative

Lattice Boltzmann method and RANs approach for simulation of turbulent flows and particle transport and deposition

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Particuology 2017年第1期15卷 62-72页

作者： H. sajjadi M. salmanzadeh g. Ahmadi s. jafari Department of Mechanical Engineering Shahid Bahonar University ofKerman Kerrnan lran Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY USA Department of Petroleum Engineering Shahid Bahonar University ofKerrnan Kerman lran

Using the lattice-Boltzmann computational approach in conjunction with the Reynolds averaged Navier-stokes （RANs） model, several turbulent flows and the transport and deposition of particles in different passages were studied. The new lattice Boltzmann method （LBM） solved the RANs equations coupled with the standard and renormalization group k-E turbulence models. In particular, the LBM formulation was augmented by the addition of two transport equations for the probability distribution function of populations of k and 8. The discrete random walk model was used to generate the instanta- neous turbulence fluctuations. For turbulent channel flows, the analytical fits to the root mean-square velocity fluctuations obtained by the direct numerical simulation of the turbulent flow were used in the analysis. Attention was given to the proper evaluation of the wall normal turbulent velocity fluctuations particularly near the wall. The simulation results were compared with the available numerical simulation and experimental data. The new LBM-RANs model is shown to provide a reasonably accurate description of turbulent flows and particle transport and deposition at modest computational cost.

关键词： Lattice Boltzmann method Reynolds averaged Navier-stokes Renormalization group model k-ε model Particle transport and deposition

Laser-Plasma Interaction in Presence of an Obliquely External Magnetic Field:Application to Laser Fusion without Radioactivity

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Communications in Theoretical Physics 2016年第8期65卷 237-243页

作者： M.Mobaraki s.jafari Department of Physics University of Guilan

In this paper, the nonlinear interaction of ultra-high power laser beam with fusion plasma at relativistic regime in the presence of obliquely external magnetic field has been studied. Imposing an external magnetic field on plasma can modify the density profile of the plasma so that the thermal conductivity of electrons reduces which is considered to be the decrease of the threshold energy for ignition. To achieve the fusion of Hydrogen–Boron(HB) fuel,the block acceleration model of plasma is employed. Energy production by HB isotopes can be of interest, since its reaction does not generate radioactive tritium. By using the inhibit factor in the block model acceleration of plasma and Maxwell's as well as the momentum transfer equations, the electron density distribution and dielectric permittivity of the plasma medium are obtained. Numerical results indicate that with increasing the intensity of the external magnetic field, the oscillation of the laser magnetic field decreases, while the dielectric permittivity increases. Moreover, the amplitude of the electron density becomes highly peaked and the plasma electrons are strongly bunched with increasing the intensity of external magnetic field. Therefore, the magnetized plasma can act as a positive focusing lens to enhance the fusion process. Besides, we find that with increasing θ-angle(from oblique external magnetic field) between 0 and 90°, the dielectric permittivity increases, while for θ between 90° and 180°, the dielectric permittivity decreases with increasing θ.

关键词： laser-plasma interaction external magnetic field laser fusion HB fuel

gain calculation of a free-electron laser operating with a non-uniform ion-channel guide

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Chinese Physics B 2011年第9期20卷 187-191页

作者： A.Hasanbeigi H.Mehdian s.jafari Department of Physics and Plasma Research Institute of Tarbiat Moallem University 49 Dr Mofatteh AvenueTehran 15614Iran Department of Physics University of GuilanRasht 41335-1914Iran

Amplification of an electromagnetic wave by a free electron laser （FEL） with a helical wiggler and an ion channel with a periodically varying ion density is examined. The relativistic equation of motion for a single electron in the combined wiggler and the periodic ionbchannel fields is solved and the classes of possible trajectories in this configuration are discussed. The gain equation for the FEL in the low-gain-per-pass lirnit is obtained by adding the effect of the periodic ion channel. Numerical calculation is employed to analyse the gain induced by the effects of the non-uniform ion density. The variation of gain with ion-channel density is demonstrated. It is shown that there is a gain enhancement for group I orbits in the presence of a non-uniform ion-channel but not in a uniform one. It is also shown that periodic ion-channel guiding is used to reach the maximum peak gain in a low ion-channel frequency （low ion density）.

关键词： free electron laser nonuniform ion-channel helical wiggler

Mixed finite element and differential quadrature method for free and forced vibration and buckling analysis of rectangular plates

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Applied Mathematics and Mechanics(English Edition) 2012年第1期33卷 81-98页

作者： s. A. EFTEKHARI A. A. jafari Department of Mechanical Engineering K. N. Toosi University of Technology

This paper presents a combined application of the finite element method （FEM） and the differential quadrature method （DQM） to vibration and buckling problems of rectangular plates. The proposed scheme combines the geometry flexibility of the FEM and the high accuracy and efficiency of the DQM. The accuracy of the present method is demonstrated by comparing the obtained results with those available in the literature. It is shown that highly accurate results can be obtained by using a small number of finite elements and DQM sample points. The proposed method is suitable for the problems considered due to its simplicity and potential for further development.

关键词： finite element method (FEM) differential quadrature method (DQM) rectangular plate free and forced vibration buckling analysis

Thermo-electromechanical behavior of functionally graded piezoelectric hollow cylinder under non-axisymmetric loads

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Applied Mathematics and Mechanics(English Edition) 2015年第7期36卷 939-954页

作者： A.ATRIAN J.jafari FEsHARAKI s.H.NOURBAKHsH Department of Mechanical Engineering Najafabad BranchIslamic Azad University Faculty of Engineering Shahrekord University

This paper presents an analytical solution of a thick walled cylinder composed of a functionally graded piezoelectric material （FgPM） and subjected to a uniform electric field and non-axisymmetric thermo-mechanical loads. All material properties, except Poisson＇s ratio that is assumed to be constant, obey the same power law. An exact solution for the resulting Navier equations is developed by the separation of variables and complex Fourier series. stress and strain distributions and a displacement field through the cylinder are obtained by this technique. To examine the analytical approach, different examples are solved by this method, and the results are discussed.

关键词： functionally graded piezoelectric material (FgPM) thermoelasticity Fourierseries non-axisymmetric