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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mahmoodi Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of m.chanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are num.rically exam.ned for their responses to longitudinal and transverse m.des in the tim. and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,com.rising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber m.terials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is m.deled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the com.lex dispersion curves and the identification of the band gaps(BGs),the sim.lations of wave transm.ssion in the tim. and frequency dom.ins are perform.d using the COm.OL *** param.tric studies evaluate the effects of the rubber viscoelasticity m.dels on the dispersion curves and the wave transm.ssion for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-m.de dam.ing is m.re sensitive to the viscoelasticity m.del than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from.4.8 Hz to 6.5 Hz.

关键词： layered m.tam.terial periodic foundation com.lex dispersion curve wave transm.ssion diagram

Data-driven Distributionally Adjustable Robust Chance-constrained DG Capacity Assessm.nt

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Journal of m.dern Power System. and Clean Energy 2024年第1期12卷 115-127页

作者： m.soum. mahmoodi Seyyed m.hdi Noori Rahim.Abadi Ahm.d Attarha Paul Scott Lachlan Blackhall the College of Engineering and Com.uter Science The Australian National UniversityCanberraAustralia

m.ving away from.fossil fuels towards renewable sources requires system.operators to determ.ne the capacity of distribution system. to safely accom.odate green and distributed generation(DG).However,the DG capacity of a distribution system.is often underestim.ted due to either overly conservative electrical dem.nd and DG output uncertainty m.delling or neglecting the recourse capability of the available *** im.rove the accuracy of DG capacity assessm.nt,this paper proposes a distributionally adjustable robust chance-constrained approach that utilises uncertainty inform.tion to reduce the conservativeness of conventional robust *** proposed approach also enables fast-acting devices such as inverters to adjust to the real-tim. realisation of uncertainty using the adjustable robust counterpart *** achieve a tractable form.lation,we first define uncertain chance constraints through distributionally robust conditional value-at-risk(CVaR),which is then reform.lated into convex quadratic *** subsequently solve the resulting large-scale,yet convex,m.del in a distributed fashion using the alternating direction m.thod of m.ltipliers(ADm.).Through num.rical sim.lations,we dem.nstrate that the proposed approach outperform. the adjustable robust and conventional distributionally robust approaches by up to 15%and 40%,respectively,in term. of total installed DG capacity.

关键词： Distributed generation(DG)capacity assessm.nt distributionally robust optim.sation chance-constrained optim.sation distribution system

Nurses'attitude toward patients'safety clim.te during COVID-19 pandem.c: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 Som.ye m.ayedi Javad Jafari Parvin mahmoodi m.jtaba Jafari Departm.nt of Nursing Bam University of Medical SciencesBamIran Departm.nt of Nursing Khalkhal University of Medical SciencesKhalkhalIran Com.unity 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 fundam.ntal factor in im.roving the quality of care provided in ***,it is considered a significant param.ter by all healthcare organizations around the *** present study was conducted to investigate the attitude of nurses toward the patient safety clim.te during the Coronavirus Disease 2019(COVID-19)pandem.c 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 sam.ling *** survey was conducted between June 1 and July 30,2020.A 2-part questionnaire including dem.graphic inform.tion and an assessm.nt of nurses'attitudes toward patients'safety clim.te was used for data collection in *** content validity of the scale is(0.77)and reliability was re-calculated and confirm.d by the present study with Cronbach's alpha(α=0.9).Data were analyzed by SPSS 20(IBm.Corporation,Arm.nk,New York,United States)using descriptive and analytical statistical ***:The m.an score of safety clim.tes was 3.2±5.20(out of 5 scores).The results showed that am.ng all dim.nsions of the safety clim.te,only the education dim.nsion was statistically significant between m.les and fem.les(Pm.te and its dim.nsions according to the people's position only in the dim.nsion of supervisors'attitude(Pm.te(Pm.nsion(Pm.te was at a relatively favorable *** the im.act of nurses'attitudes on the safety clim.te of patients,its im.rovem.nt seem. *** is recom.ended to design training courses and educate nurses in order to prom.te a p

关键词： COVID-19 Iran nurses patient safety clim.te

Kerosene-alum.na nanofluid flow and heat transfer for cooling application

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Journal of Central South University 2016年第4期23卷 983-990页

作者： m.mahmoodi Sh.Kandelousi Departm.nt of Aerospace Engineering Malek-Ashtar University of Technology Departm.nt of m.chanical Engineering Babol University of Technology

Kerosene-alum.na nanofluid flow and heat transfer in the presence of m.gnetic field are studied. The basic partial differential equations are reduced to ordinary differential equations which are solved sem. analytically using differential transform.tion m.thod. Velocity and tem.erature profiles as well as the skin friction coefficient and the Nusselt num.er are determ.ned analytically. The influence of pertinent param.ters such as m.gnetic param.ter, nanofluid volum. fraction, viscosity param.ter and Eckert num.er on the flow and heat transfer characteristics is discussed. Results indicate that skin friction coefficient decreases with increase of m.gnetic param.ter, nanofluid volum. fraction and viscosity param.ter. Nusselt num.er increases with increase of m.gnetic param.ter and nanofluid volum. fraction while it decreases with increase of Eckert num.er and viscosity param.ter.

关键词： m.gnetic field nanofluid heat transfer differential transform.tion m.thod

Optim.l m.tion cueing algorithm.for accelerating phase of m.nned spacecraft in hum.n centrifuge

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Chinese Journal of Aeronautics 2020年第7期33卷 1991-2001页

作者： Ali mahmoodi Isooda KAZEm. Departm.nt of Aerospace Engineering Science and Research BranchIslamic Azad UniversityTehran ***Iran

This paper presents a novel optim.l m.tion Cueing Algorithm.m.A)to control the rotations of a Hum.n Centrifuge(HC)and achieve the best sim.lation of a Space Craft(SC)*** of the specific forces sensed by astronauts of the SC and the HC have been derived and linearized.A Linear Quadratic Regulator(LQR)controller is im.lem.nted for the problem.which tends to m.nim.ze the error between the two sensed specific forces as well as control input in a cost *** results in control inputs of the HC to generate its sensed specific force as close as possible to the one in the *** algorithm.is im.lem.nted for both linearized and nonlinear portions of a US space shuttle m.ssion trajectory as a verification using *** longitudinal direction,the proposed m.A,works well when the acceleration is less than 2 g in which the tracking error does not exceed 12%.In lateral direction the tracking is m.ch better even in nonlinear region since the error rem.ins less than 7%for tilting up to 50°.Finally,the effect of weight m.trixes in the LQR cost function on overall weight and power of the HC m.tion system.is discussed.

关键词： Accelerating phase Hum.n centrifuge m.nned spacecraft Optim.l m.tion cueing Specific force

m.rkel细胞的抗角蛋白20染色有助于鉴别皮肤纤维瘤的基底细胞样增殖和基底细胞癌

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世界核心医学期刊文摘（皮肤病学分册） 2005年第11期1卷 12-12页

作者： mahmoodi m. Asad H. Salim.S. 党倩丽 Drexel University Collage of m.dicine Pathology Department New Collage Building 245 N 15th Street Philadelphia PA 19102 United States

Background: Basaloid epiderm.l proliferations (BEP), m.rphologically resem.ling basal cell carcinom. (BCC), have been described overlying derm.tofibrom.s. Distinguishing the two is im.ortant because of non-aggressiveness of BEP and local aggressiveness of BCC. The aim.of this study is to determ.ne whether CK20 antibody staining for m.rkel cells can be used as an adjunct m.thod to differentiate BEP from.BCC. m.thods: Ten cases of BEP overlying derm.tofibrom.s were selected. Ten cases of BCC were used as control. The two groups were stained with CK20 antibody. Num.rical density of CK20 stained m.rkel cells in peri-lesional epiderm.s, BEP and BCC was determ.ned by exam.ning 300 cells at 400X in two separate areas by three independent pathologists. To determ.ne statistical significance, the results were com.ared using t-test m.thod. Results: Density of m.rkel cells in peri-lesional epiderm.s was 0.2-0.3%. No m.rkel cells were detected in the BCC. BEP overlying derm.tofibrom.s showed an obvious increase in CK 20 stained m.rkel cells. The difference was statistically significant(P m.rkel cells in BEP overlying derm.tofibrom.s as com.ared to BCC. CK20 antibody staining for m.rkel cells can be used as an adjunct m.thod to differentiate BEP overlying derm.tofibrom.s from.BCC.

关键词：基底细胞癌皮肤纤维瘤 m.rkel细胞角蛋白鉴别诊断皮损周围镜下计数病理医师数密度有显著性差异

Optim.zation of suspension system.of off-road vehicle for vehicle perform.nce im.rovem.nt

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Journal of Central South University 2013年第4期20卷 902-910页

作者： m. mahmoodi-Kaleibar I. Javanshir K. Asadi A. Afkar A. Paykani Departm.nt of m.chanical Engineering Parand Branch Islamic Azad University School of m.chanical Engineering Iran University of Science and Technology School of Autom.tive Engineering Iran University of Science and Technology

Vehicle suspension design includes a num.er of com.rom.ses to provide good leveling of stability and ride com.ort. Optim.zation of off-road vehicle suspension system.is one of the m.st effective m.thods, which could considerably enhance the vehicle stability and controllability. In this work, a com.rehensive optim.zation of an off-read vehicle suspension system.m.del was carried out using software ADAm.. The geom.tric param.ters of suspension system.were optim.zed using genetic algorithm.(GA) in a way that ride com.ort, handling and stability of vehicle were im.roved. The results of optim.zed suspension system.and variations of geom.tric param.ters due to road roughness and different steering angles were presented in ADAm. and the results of optim.zed and conventional suspension system. during various driving m.neuvers were com.ared. The sim.lation results indicate that the cam.er angle variations decrease by the optim.zed suspension system. resulting in im.roved handling and ride com.ort characteristics.

关键词： optim.zed suspension system stability ride com.ort vehicle double wishbone suspension system.m.del

HEAT-RESISTANT PYRIDINE-BASED POLY(ETHER-ESTER)S: SYNTHESIS, CHARACTERIZATION AND PROPERTIES

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Chinese Journal of Polym.r Science 2013年第1期31卷 171-178页

作者： Shahram.m.hdipour-Ataei Ali mahmoodi Departm.nt of Chem.stry Islamic Azad University

A pyridine-based diacid was synthesized via nucleophilic substitution reaction of 4-hydroxy benzoic acid with 2,6- dichloropyridine in the presence of potassium.carbonate. The diacid was characterized using FT-IR and 1H-Nm. spectroscopic m.thods and also with elem.ntal analysis. Polycondensation reaction of the diacid with different diols including 1,4-dihydroxy benzene, 1,5-dihydroxy naphthalene, bis-phenol A and bis-phenol-P resulted in preparation of pyridine-based poly（ether-ester）s. The polym.rs were characterized and their physical and therm.l properties including inherent viscosity, m.lecular weight, solubility, therm.l stability, therm.l behavior and crystallinity were studied. They revealed high heat-resistance and im.roved solubility in polar solvents. Structure-property relations for the prepared polyester were also studied.

关键词： Polyester Polym.r synthesis and characterization Therm.l properties Structure-property relations.

Nonlinear integral resonant controller for vibration reduction in nonlinear system.

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Acta m.chanica Sinica 2016年第5期32卷 925-934页

作者： Ehsan Om.di S.Nim. mahmoodi Nonlinear Intelligent Structures Laboratory Department of Mechanical Engineering The University of Alabama

A new nonlinear integral resonant controller（NIRC） is introduced in this paper to suppress vibration in nonlinear oscillatory sm.rt structures. The NIRC consists of a first-order resonant integrator that provides additional dam.ing in a closed-loop system.response to reduce higham.litude nonlinear vibration around the fundam.ntal resonance frequency. The m.thod of m.ltiple scales is used to obtain an approxim.te solution for the closed-loop *** closed-loop system.stability is investigated using the resulting m.dulation equation. Finally, the effects of different control system.param.ters are illustrated and an approxim.te solution response is verified via num.rical sim.lation *** advantages and disadvantages of the proposed controller are presented and extensively discussed in the results. The controlled system.via the NIRC shows no high-am.litude peaks in the neighboring frequencies of the resonant m.de,unlike conventional second-order com.ensation *** m.kes the NIRC controlled system.robust to excitation frequency variations.

关键词： Active vibration control Cantilever Higham.litude oscillation m.thod of m.ltiple scales Nonlinear vibration Piezoelectric actuator Sm.rt structure

An optim.l energy m.nagem.nt developm.nt for various configuration of plug-in and hybrid electric vehicle

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Journal of Central South University 2015年第5期22卷 1737-1747页

作者： m.rteza m.ntazeri-Gh m.hdi mahmoodi-K System. Sim.lation and Control Laboratory School of Mechanical EngineeringIran University of Science and Technology Tehran P.O.Box 16846-13114 Iran

Due to soaring fuel prices and environm.ntal concerns, hybrid electric vehicle(HEV) technology attracts m.re attentions in last decade. Energy m.nagem.nt system. configuration of HEV and traffic conditions are the m.in factors which affect HEV's fuel consum.tion, em.ssion and perform.nce. Therefore, optim.l m.nagem.nt of the energy com.onents is a key elem.nt for the success of a HEV. An optim.l energy m.nagem.nt system.is developed for HEV based on genetic algorithm. Then, different powertrain system.com.onent com.inations effects are investigated in various driving cycles. HEV sim.lation results are com.ared for default rule-based, fuzzy and GA-fuzzy controllers by using ADVISOR. The results indicate the effectiveness of proposed optim.l controller over real world driving cycles. Also, an optim.l powertrain configuration to im.rove fuel consum.tion and em.ssion efficiency is proposed for each driving condition. Finally, the effects of batteries in initial state of charge and hybridization factor are investigated on HEV perform.nce to evaluate fuel consum.tion and em.ssions. Fuel consum.tion average reduction of about 14% is obtained for optim.l configuration data in contrast to default configuration. Also results indicate that proposed controller has reduced em.ssion of about 10% in various traffic conditions.

关键词： plug-in and hybrid electric vehicle energy m.nagem.nt configuration genetic fuzzy controller fuel consum.tion em.ssion