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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 917-931页

作者： alireza kiani Mehdi Torabi S.Mohammad Mirhosseini Department of Civil Engineering Islamic Azad University Arak Branch Arak 12346 Iran Department of Civil Engineering Islamic Azad University Kangan Branch Kangan 12345 Iran Department of Civil Engineering Islamic Azad University Arak Branch Arak 34125 Iran

Ground-motion Intensity Measures (IMs) are used to quantify the strength of ground motions and evaluate the response of structures. IMs act as a link between seismic demand and seismic hazard analysis and therefore, have a key role in performance-based earthquake engineering. Many studies have been carried out on the determination of suitable IMs in terms of effi ciency, suffi ciency and scaling robustness. The majority of these investigations focused on ordinary structures such as buildings and bridges, and only a few were about buried pipelines. In the current study, the optimal IMs for predicting the seismic demand of continuous buried steel pipelines under near-fi eld pulse-like ground motion records is investigated. Incremental dynamic analysis is performed using twenty ground motion records. Using the results of the regression analysis, the optimality of 23 potential IMs are studied. It is concluded that specifi c energy density (SED) followed by VSI[ω1(PGD+RMSd )] are the optimal IMs based on effi ciency, suffi ciency and scaling robustness for seismic response evaluation of buried pipelines under near-fi eld ground motions.

关键词： continuous buried steel pipeline intensity measure scaling robustness pulse-like ground motion records performance-based earthquake engineering

Analysis of Linear and Nonlinear Vibrations of Composite Rectangular Sandwich Plates with Lattice Cores

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Computers, Materials & Continua 2025年第1期82卷 223-257页

作者： alireza Moradi alireza Shaterzadeh Faculty of Mechanical Engineering Shahrood University of TechnologyShahroodP.O.Box ***Iran

For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this *** plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to *** this purpose,the partial differential equations of motion have been derived based on the first-order shear deformation theory,employing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain ***,the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation(Duffing equation)by applying the Galerkin *** the solution of this equation,the natural frequencies are ***,to calculate the non-linear frequencies of the plate,the non-linear equation of the plate has been solved analytically using the method of multiple ***,the effect of some critical parameters of the system,such as the thickness,height,and different angles of the stiffeners on the linear and nonlinear frequencies,has been analyzed in *** confirmthe solution method,the results of this research have been compared with the reported results in the literature and finite elements in ABAQUS,and a perfect match is *** results reveal that the geometry and configuration of core ribs strongly affect the natural frequencies of the plate.

关键词： Free vibration composite sandwich plate lattice core galerkin method Duffing equation multiple scales method

Rainfall-induced wind erosion in soils stabilized with alkali-activated waste materials

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 465-480页

作者： alireza Komaei Abbas Soroush Seyed Mohammad Fattahi Hesam Ghanbari Department of Civil and Environmental Engineering Amirkabir University of TechnologyTehran159163431Iran

This study evaluates the efficacy of sustainable erosion control using slag-based alkali-activated cement crusts under varying rainfall and wind conditions. The rainfall intensities ranged from 30 mm/h to 120 mm/h, with durations ranging from 15 min to 90 min, and crust slopes of ∼2° (gentle) and 30° (steep). Wind tunnel experiments were conducted at wind velocities of 14 m/s, 21 m/s, and 28 m/s to investigate post-rainfall wind erodibility, along with changes in crust strength and microstructure analysis. The findings show the development of hydrated cementitious phases in alkali-activated material, which form around and between the particles during the alkaline activation process. Alkali-activated cement crusts significantly reduced erosion caused by rainfall and subsequent wind by several orders of magnitude. At the highest rainfall intensity of 120 mm/h, rainfall erosion was measured to be 1654.81 kg/m2 for untreated samples and 0.89 kg/m2 for treated samples, demonstrating a substantial 99.95% reduction in erosion due to the treatment. Similarly, at the highest wind speed tested, wind erosion was 122.75 kg/m2 for untreated samples and 0.095 kg/m2 for treated samples, indicating a significant 99.92% reduction in erosion due to the formation of an alkali-activated cement crust on the soil surface. However, exposure of the samples to 120 mm/h rainfall for 90 min resulted in a 5.2-fold increase in wind erosion compared to pre-rainfall conditions. Similarly, penetrometer results indicated a 37%–54% reduction in post-rainfall surface strength.

关键词： Rainfall erosion Alkali-activated material Wind erosion Crust formation

Psychometric Validation of the Persian Version of the Cannabis Use Disorder Identification Test

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Open Journal of Medical Psychology 2025年第1期14卷 71-96页

作者： Mahmood Amirinia Benjamin Ghasemi Parisa Aghazadeh alireza Mollazadeh Faculty of Medicine Sciences West Tehran Branch of Islamic Azad University Tehran Iran School of Environment and Natural Resources The Ohio State University Columbus Ohio USA Department of Psychology and Social Science Central Branch of Islamic Azad University Tehran Iran Department of Psychology Ashtian Branch of Islamic Azad University Ashtian Iran

The purpose of this paper is to look into how reliable and valid the Persian version of the Cannabis Use Disorder Identification Test-Revised (CUDIT-R-Pr) is. It will also compare the screening features of the CUDIT-R with those of the DSM-5 criteria for cannabis use disorder (CUD) based on the SCID-5-CT in a group of university students in Tehran, Iran. The study used the stratified random sampling technique to collect data from 541 students (19 to 24 years old) who used cannabis in Tehran universities in 2024. Confirmatory factor analysis confirmed the uni-dimensionality of the CUDIT-R-Pr. We checked the reliability of the CUDIT-R-Pr using Cronbach Alpha, split-half, inter-rater, test-retest stability over time, and parallel testing equivalence. The results indicated that CUDIT-R-Pr is reliable, reproducible, and responsive, with substantial agreement and adequate interpretability. The CUDIT-R shows that it can tell the difference between different levels of cannabis use severity, which is known as discriminant validity. Receiver operating characteristic analyses confirmed this, using an area under the receiver operating characteristics curve (AUC = 0.95) at a cutoff of ten or less. This allowed CUDIT-R-Pr to accurately predict any DSM-5 based on the highest correctly classified value (0.89), demonstrating high levels of sensitivity (0.96), specificity (0.69), and Youden value (0.65). The exact maximum Youden index (0.72) showed that CUDIT-R-Pr could also predict moderate DSM-5 with a cutoff of twelve or less. To validate and generalize the CUDIT-R-Pr for use among Iranian cannabis users, we need more research.

关键词： Cannabis Use Disorder Marijuana Psychometrics Validity Reliability Iran

Microstructures, mechanical properties, corrosion, and biocompatibility of extruded Mg-Zr-Sr-Ho alloys for biodegradable implant applications

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Journal of Magnesium and Alloys 2023年第1期11卷 110-136页

作者： Faisal kiani Jixing Lin alireza Vahid Khurram Munir Cuie Wen Yuncang Li School of Engineering RMIT UniversityMelbourneVictoria 3001Australia School and Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027China Institute for Frontier Materials Deakin UniversityGeelongVictoria 3217Australia

In this study,the microstructures,mechanical properties,corrosion behaviors,and biocompatibility of extruded magnesium-zirconiumstrontium-holmium(Mg-Zr-Sr-Ho)alloys were comprehensively *** effect of different concentrations of Ho on the microstructural characteristics,tensile and compressive properties,corrosion resistance,and biocompatibility were *** microstructures of the extruded Mg-1Zr-0.5Sr-xHo(x=0.5,1.5,and 4 wt.%)alloys consisted ofα-Mg matrix,fineα-Zr particles,and intermetallic phase particles of Mg_(17)Sr_(2) and Ho_(2)Mg mainly distributed at the grain ***{1012}tensile twins were observed in the partially recrystallized samples of Mg-1Zr-0.5Sr-0.5Ho and *** addition of Ho to 4 wt.%resulted in a complete recrystallization due to activation of the particle stimulated nucleation around the Mg_(17)Sr_(2) *** evolution of a rare earth(RE)texture was observed with the Ho addition,which resulted in the weakened basal and prismatic ***,a drastic increase of 200%in tensile elongation and 89%in compressive strain was observed with Ho addition increased from 0.5 to 4 wt%,*** tension-compression yield asymmetry was significantly decreased from 0.62 for Mg-1Zr-0.5Sr-0.5Ho to 0.98 for Mg-1Zr-0.5Sr-4Ho due to the weakening of *** analysis of the extruded Mg-Zr-Sr-Ho alloys revealed the presence of pitting corrosion.A minimum corrosion rate of 4.98 mm y^(−1) was observed in Mg-1Zr-0.5Sr-0.5Ho *** enhanced corrosion resistance is observed due to the presence of Ho_(2)O_(3) in the surface film which reduced galvanic *** formation of a stabilized surface film due to the Ho_(2)O_(3) was confirmed through the electrical impedance spectroscopy and XPS *** in vitro cytotoxicity assessment revealed good biocompatibility and cell adhesion in relation to SaOS2 cells.

关键词： Mg-Zr-Sr-Ho alloy Mechanical properties Corrosion Cytotoxicity EBSD Electrical impedance spectroscopy Potentiodynamic polarization

Performance and ruminal parameters of fattening Moghani lambs fed recycled poultry bedding

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Animal Nutrition 2017年第2期3卷 145-150页

作者： Ayoub Azizi Afrooz Sharifi Arash Azarfar Ali kiani alireza Jolazadeh Animal Science Group Faculty of Agricultural SciencesLorestan University Animal Science Department Khuzestan Ramin Agricultural and Natural Resources University

This study investigated the effects of recycled poultry bedding(RPB) on performance and protozoa population, microbial enzyme activity and microbial protein synthesis(MPS) in rumen contents of fattening lambs. Thirty-six male Moghani lambs(31.4 ± 3.2 kg body weight) were fed iso-energetic and iso-nitrogenous diets containing 0, 70,140 or 210 g/kg dry matter(DM) RPB in a balanced randomized design(9 lambs per treatment). Results showed that final body weight, DM intake, average daily gain and feed conversion ratio were unchanged(P > 0.05) by RPB inclusion. Total protozoa population and subfamily of Entoniniinae and Diplodiniiae were linearly decreased by RPB(L, P 0.05) by feeding the experimental diets. Inclusion of RPB in the diet linearly decreased extra cellular and total a-amylase activity(L, P 0.05). The extra cellular activity of proteases tended to increase(L, P=0.07) and their total and cellular activity increased(P > 0.05) in lambs fed RPB. Incorporation of RPB into the diet had no effect(L, P > 0.05) on urinary purine derivative excretion and MPS. In conclusion, inclusion of RPB up to 210 g/kg DM had no negative impact on performance, ruminal fibrolytic enzyme activity and MPS, while it increased rumen protease activity and decreased protozoa population in fattening Moghani lambs.

关键词： Recycled poultry bedding Performance Enzyme activity Microbial protein Lamb

Attitude of acute care nurses to the family presence during resuscitation and emotional intelligence:a cross sectional study

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Frontiers of Nursing 2025年第1期12卷 107-114页

作者： Amir Hooshmand alireza Sadeghi Sajad Noorian Mojtaba Senmar Yasamin Mehri Amirhosein Babaei Najmeh Chegini Student Research Committee Qazvin University of Medical SciencesQazvinIran Department of Statistics Faculty of ScienceUniversity of QomQomIran Student Research Committee Social Determinants of Health Research CenterResearch Institute for Prevention of Non-Communicable DiseasesQazvin University of Medical SciencesQazvinIran

Objective:Cardiopulmonary resuscitation(CPR)is one of the most important life-saving procedures in the *** to medical guidelines,family presence during CPR is still not accepted in some *** presence during CPR depends on the nurses’attitude,which is influenced by various *** intelligence(EI)helps nurses make wise decisions and display responsible behavior,which is necessary for proper and good performance in *** study’s purpose was to determine the attitude of acute care nurses toward family presence during CPR and its relationship with ***:The descriptive-analytical study was conducted among the nurses of acute care units(intensive care unit[ICU],critical care unit,and emergency department)in teaching hospitals of Qazvin University of Medical Sciences,Iran,in 2022-2023.A total of 186 nurses were included in the study using convenience *** data collection tools were a checklist of demographic characteristics,nurses’attitude toward the presence of family scale,and Siberia Schering’s EI *** collected data were analyzed using descriptive and analytical statistics and SPSS ***:The mean age of the participants was(32.05±6.93)*** 186 nurses participating in the study,127(68.3%)were women and the rest were *** mean score of attitude was 47.41±9.41(the minimum score of the nurses was 19 and the maximum score was 95).The mean score of EI was 99.27±8.86(the minimum score was 69 and the maximum score was 128).The results of Pearson’s correlation coefficient showed no significant relationship between the total score of attitude and EI of the participants(P=0.588).Data analysis showed that only the self-arousal dimension of EI has a significant relationship with the range of family self-control behaviors in attitude(P=0.037).Conclusions:The results showed that the nurses of acute care units have a positive attitude toward the presence of the family during CPR and have high ***

关键词： attitude cardiopulmonary resuscitation critical care emotional intelligence family presence nurse

Stress analysis of thermally affected rotating nanoshafts with varying material properties

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Acta Mechanica Sinica 2016年第5期32卷 813-827页

作者： Keivan kiani Department of Civil Engineering K.N. Toosi University of Technology

Based on the surface elasticity theory of GurtinMurdoch, thermo-elastic fields within rotating nanoshafts with varying material properties subjected to a thermal field are explicitly examined. Accounting for the surface energy effect, the nonclassical boundary conditions are enforced in the cases of fixed-free and free-free conditions. The effects of variation of material properties, temperature of the environment, angular velocity, and radius of the outer radius on the radial displacement, hoop and radial stresses are investigated. In all performed studies, the role of the surface effect on the thermo-elastic field of the nanostructure is methodically discussed.

关键词： Rotating nanoshaft Thermo-elastic field Surface energy effect Non-classical boundary conditions Analytical modeling

Modified consecutive modal pushover procedure for seismic investigation of one-way asymmetric-plan tall buildings

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Earthquake Engineering and Engineering Vibration 2012年第2期11卷 221-232页

作者： Faramarz Khoshnoudian Mahdi kiani Department of Civil Engineering Amirkabir University of TechnologyTehranIran

The effects of higher modes and torsion have a significant impact on the seismic responses of asymmetric-plan tall buildings. A consecutive modal pushover (CMP) procedure is one of the pushover methods that have been developed to consider these effects. The aim of this paper is to modify the (CMP) analysis procedure to estimate the seismic demands of one-way asymmetric-plan tall buildings with dual systems. An analysis of 10-, 15- and 20-story asymmetric-plan buildings is carried out, and the results from the modified consecutive modal pushover (MCMP) procedure are compared with those obtained from the modal pushover analysis (MPA) procedure and the nonlinear time history analysis (NLTHA). The MCMP estimates of the seismic demands of one-way asymmetric-plan buildings demonstrate a reasonable accuracy, compared to the results obtained from the NLTHA. Furthermore, the accuracy of the MCMP procedure in the prediction of plastic hinge rotations is better than the MPA procedure. The new pushover procedure is also more accurate than the FEMA load distribution and the MPA procedure.

关键词： modified consecutive modal pushover seismic demands nonlinear time history analysis asymmetric-plan tall buildings torsion

On the limitations of linear beams for the problems of moving mass-beam interaction using a meshfree method

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Acta Mechanica Sinica 2012年第1期28卷 164-179页

作者： Keivan kiani Ali Nikkhoo Department of Civil Engineering Islamic Azad University Department of Civil Engineering University of Science and Culture

This paper deals with the capabilities of linear and nonlinear beam theories in predicting the dynamic response of an elastically supported thin beam traversed by a moving mass. To this end, the discrete equations of motion are developed based on Lagrange＇s equations via reproducing kernel particle method （RKPM）. For a particular case of a simply supported beam, Galerkin method is also employed to verify the results obtained by RKPM, and a reasonably good agreement is achieved. Variations of the maximum dynamic deflection and bending moment associated with the linear and nonlinear beam theories are investigated in terms of moving mass weight and velocity for various beam boundary conditions. It is demonstrated that for majority of the moving mass velocities, the differences between the results of linear and nonlinear analyses become remarkable as the moving mass weight increases, particularly for high levels of moving mass velocity. Except for the cantilever beam, the nonlinear beam theory predicts higher possibility of moving mass separation from the base beam compared to the linear one. Furthermore, the accuracy levels of the linear beam theory are determined for thin beams under large deflections and small rotations as a function of moving mass weight and velocity in various boundary conditions.

关键词： Nonlinear beam theory Moving mass-beam in- teraction Euler-Bernoulli beam theory - Reproducing kernel particle method (RKPM) Galerkin method (GM)