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Earth return path impedances of underground cable for three-layer earth

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1191-1198页

作者： b.HEMMATIAN b.vahidi S.H.HOSSEINIAN Department of Electrical Engineering Amirkabir University of Technology

One of the factors that affect the parameters of an underground cable is earth return path *** developed a formula for the case of one-layer(homogenous) *** in practice the earth is composed of several *** this study we develop a new formula for earth return path impedance in the case of a three-layer *** check the accuracy of the obtained results,a comparison has been made with the finite element method(FEM).A comparison between the results of the Pollaczek formula and results of the obtained formula for a three-layer earth has been made,showing that the use of the Pollaczek formula instead of the actual formula can cause serious errors.

关键词： Underground cables Earth return path impedance Earth stratification Finite element method (FEM)

Three Phase Transformer Modeling with Consideration the Core Effect

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Three Phase Transformer Modeling with Consideration the Core...

Niosome-encapsulated auraptene reduced the mRNA expression of VEGF-A and PDGFs genes in human retinaderived RPE cell line

11th International Conference on Electrical Machines and Systems

作者： S.Javadi b.vahidi S.H.Hosseinian Department of Electrical and Computer Engineering Islamic Azad University of KashanIran Department of Electrical Engineering Amirkabir University of TechnologyIran

＜正＞The transformer model described in the present paper belongs to the class of low frequency *** generation of the core parameters for the model is easy,and it does not require any substantial skills on the part of the user. The transformer model was originally developed as a model for the study of harmonics due to the non-linear effect of the *** model can also be used for the investigation of magnetizing inrush current.

关键词： Three phase transformer Model Core Low frequency

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1028-1035页

作者： Akram vahidi Teymoor Khosravi Farzad Dastaviz Mehdi Sheikh Arabi Ayyoob Khosravi Morteza Oladnabi Student Research Committee Golestan University of Medical SciencesGorgan ***Iran Department of Medical Nanotechnology Faculty of Advanced Medical TechnologiesGolestan University of Medical SciencesGorgan ***Iran Stem Cell Research Center Golestan University of Medical SciencesGorgan ***Iran Department of Molecular Medicine Faculty of Advanced Medical TechnologiesGolestan University of Medical SciencesGorgan ***Iran Gorgan Congenital Malformations Research Center Golestan University of Medical SciencesGorgan ***Iran

AIM:To evaluate the effect of auraptene(AUR)treatment in forms of free and encapsulated in niosome nanoparticles by investigating the mRNA expression level of vascular endothelium growth factor(VEGF)-A and platelet-derived growth factors(PDGFs)in human retinal pigment epithelium(RPE)cell ***:Niosome nanocarriers were produced using two surfactants Span 60 and Tween *** cell line was treated with both free AUR and *** dosage of treatments was calculated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)*** of VEGF-A and PDGF-A,PDGF-b,PDGF-C,PDGF-D genes was measured after total RNA extraction and cDNA synthesis,using real-time polymerase chain reaction(RT-PCR).RESULTS:The highest entrapment efficiency(EE)was achieved by Span 60:cholesterol(1:1)with 64.3%.The half maximal inhibitory concentration(IC50)of free and niosome-encapsulated AUR were 38.5 and 27.78µg/mL,*** study revealed that niosomal AUR had more gradual delivery to the ***-PCR results showed reduced expression levels of VEGF-A,PDGF-A,PDGF-b,PDGF-C,and PDGF-D after treatment with both free and niosomal ***:Niosomal formulation of Span 60:cholesterol(1:1)is an effective drug delivery approach to transfer AUR to RPE ***-A,PDGF-A,PDGF-b,PDGF-C,and PDGF-D are four angiogenic factors,inhibiting which by niosomal AUR may be effective in age-related macular degeneration.

关键词： auraptene niosome age-related macular degeneration angiogenesis nanocarrier

Evaluation of suspended load transport rate using transport formulas and arti- ficial neural network models (Case study: Chelchay Catchment)

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Journal of Hydrodynamics 2013年第3期25卷 459-470页

作者： HADDADCHI Arman MOVAHEDI Neshat vahidi Elham OMID Mohammad Hossein DEHGHANI Amir Ahmad Australian Rivers Institute Griffith University Nathan QLD 4111 Australia Department of Water Engineering Gorgan University of Agricultural Sciences and Natural Resources GorganIran Department of Irrigation and Reclamation Engineering University of Tehran Karaj Iran

Accurate estimation of sediment load or transport rate is very important to a wide range of water resources projects. This study was undertaken to determine the most appropriate model to predict suspended load in the Chelehay Watershed, northeast of Iran. In total, 59 data series were collected from four gravel bed-rivers and a sand bed river and two depth integrating suspended load samplers to evaluate nine suspended load formulas and feed forward backpropagation Artificial Neural Network （ANN） structures. Although the Chang formula with higher correlation coefficient （r = 0.69） and lower Root Mean Square Error （RMSE = 0.013） is the best suspended load predictor among the nine studied formulas, the ANN models significantly outperform traditional suspended load formulas and show their superior performance for all statistical parameters. Among different ANN structures two models inclu- ding 4 inputs, 4 hidden and one output neurons, and 4 inputs, 4 and one hidden and one output neurons provide the best simulation with the RMSE values of 0.0009 and 0.001, respectively.

关键词： sediment transport suspended load formulas Artificial Neural Network (ANN) river engineering

Comparison of sedative effectiveness of thiopental versus midazolam in reduction of shoulder dislocation

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World Journal of Emergency Medicine 2018年第2期9卷 125-129页

作者： Elnaz vahidi Rezvan Hemati Mehdi Momeni Amirhossein Jahanshir Morteza Saeedi Emergency Medicine Research Center Shariati Hospital Emergency Medicine Department Tehran University of Medical Sciences

bACKGROUND: Various sedative drugs have been proposed to control anxiety and agitation in shoulder dislocation, but none of them has been diagnosed as the best sedative and relaxant agent. The study aimed to compare the sedative effectiveness of thiopental versus midazolam in reduction of shoulder ***: A randomized double-blind controlled trail was performed in 80 patients with shoulder dislocation recruited from the emergency department. Ten patients were excluded and 70 patients were enrolled in the study. Case group received intravenous thiopental 2 mg/kg+2 μg/kg fentanyl while control group received intravenous midazolam 0.1 mg/kg+2 μg/kg fentanyl. Number of times, patients and physician's satisfaction, difficulty of procedure, degree of muscle relaxation, time of sedation and complete recovery, number of patients with apnea episode, O2 saturation, patient's pain score and adverse events were all ***: Muscular tone had significant difference between the two groups(P-value=0.014) and thiopental was more muscle relaxant than midazolam. Replacement of shoulder dislocation in thiopental group was easier than midazolam group(P-value=0.043). There was no need to use multiple methods of reduction in either group. before drug infusion the mean±SD VAS scores were 8.37±2.21 in the midazolam group(A) and 8.94±1.78 in the thiopental group(b); mean difference 0.57, 95% CI= –0.38 to 1.52. After completion of the procedure, the mean±SD VAS scores in group(A) and(b) were 3.20±1.30 vs. 3.65±1.30; mean difference –0.45, 95% CI= –1.07 to ***: Thiopental might be more effective and relaxant than midazolam for reduction of shoulder dislocation.

关键词： Thiopental Shoulder dislocation Midazolam Emergency medicine

New soliton wave solutions of a(2+1)-dimensional Sawada-Kotera equation

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Journal of Ocean Engineering and Science 2023年第5期8卷 527-532页

作者： Kong Debin Hadi Rezazadeh Najib Ullah Javad vahidi Kalim U.Tariq Lanre Akinyemi Department of Mathematics Yantai Nanshan UniversityShandong 265713China Faculty of Engineering Technology Amol University of Special Modern TechnologiesAmolIran Department of Mathematics COMSATS University IslamabadIslamabad 45550Pakistan Department of Applied Mathematics Iran University of Science and TechnologyTehranIran Department of Mathematical Sciences University of South AfricaPretoria 0002South Africa Department of Mathematics Mirpur University of Science and TechnologyMirpur 10250(AJK)Pakistan Department of Mathematics Lafayette CollegeEastonPennsylvaniaUnited States

In this work,we studied a(2+1)-dimensional Sawada-Kotera equation(SKE).This model depicts non-linear wave processes in shallow water,fluid dynamics,ion-acoustic waves in plasmas and other phe-nomena.A couple of well-established techniques,the bäcklund transformation based on the modified Kudryashov method,and the Sardar-sub equation method are applied to obtain the soliton wave solution to the(2+1)-dimensional *** illustrate the behavior of the nonlinear model in an appealing fashion,a variety of travelling wave solutions are formed,such as contour,2D,and 3D *** pro-posed approaches are proved more convenient and dominant for getting analytical solutions and can also be implemented to a variety of physical models representing nonlinear wave phenomena.

关键词： Modified Kudryashov method Sardar-sub equation method bäcklund transformation(2+1)-dimensional SKE Soliton wave solutions

Microstructural evolution of Al-20Si-5Fe alloy during rapid solidification and hot consolidation

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Rare Metals 2009年第6期28卷 639-645页

作者： M.Rajabi M.vahidi A.Simchi P.Davami Department of Materials Science and Engineering Sharif University of Technology Institute for Nanoscience and Nanotechnology (INST) Sharif University of Technology

Al-20Si-5Fe melt was rapidly solidified into particles and ribbons and then consolidated to near full density by hot pressing at 400℃/250 MPa/1 h. According to the eutectic-growth and dendritic-growth velocity models, the solidification front velocity and the amount of undercooling were estimated for the particles with different sizes. Values of 0.43-1.2 cm/s and 15-28 K were obtained. The secondary dendrite arm spacing revealed a cooling rate of 6 × 10^5 K/s for the particles with an average size of 20 μm. Solidification models for the ribbons yielded a cooling rate of 5 × 10^7 K/s. As a result of the higher cooling rate, the melt-spun ribbons exhibited considerable microstructural refinement and modification. The size of the primary silicon decreased from approximately 1μm to 30 nm while the formation of iron-containing intermetallic compounds was suppressed. Supersaturation of the aluminum matrix in an amount of-7 at.% Si was noticed from the XRD patterns During the hot consolidation process, coarsening of the primary silicon particles and precipitation of β-Al5FeSi phase were observed. Evaluation of the compressive strength and hardness of the alloy indicated an improvement in mechanical properties due to the microstructural modification.

关键词： Al-Si-Fe alloy rapid solidification cooling rate microstructure mechanical properties

Analgesic effect of paracetamol combined with low- dose morphine versus morphine alone on patients with biliary colic： a double blind, randomized controlled trial

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World Journal of Emergency Medicine 2016年第1期7卷 25-29页

作者： Mohammad Reza Farnia Rasoul babaei Farzaneh Shirani Mehdi Momeni Majid Hajimaghsoudi Elnaz vahidi Morteza Saeedi Emergency Medicine Department Imam Reza Hospital Kermanshah University of Medical Sciences Kermanshah Iran Emergency Medicine Department Shariati Hospital Tehran University of Medical Sciences Tehran Iran Emergency Medicine Research Center Emergency Medicine Department Shariati Hospital Tehran University of Medical Sciences Tehran Iran Emergency Medicine Department Shahid Dr Rahnemoon Hospital Shahid Sadoughi University of Medical Sciences Yazd Iran

bACKGROUND:Numerous drugs have been proposed to alleviate pain in patients with biliary colic,especially opioids,but still there is a tendency to use less narcotics because of their side effects and the unwillingness of some *** present study aimed to compare the analgesic effect of paracetamol combined with low-dose morphine versus morphine alone in patients with biliary ***:A randomized double-blind controlled trial was performed in 98 patients with biliary colic,recruited from two emergency departments from August 2012 to August *** patients were excluded and the remaining were randomized into two groups:group A received 0.05mg/kg morphine+1 000 mg paracetamol in 100 m L normal saline and group b received 0.1 mg/kg morphine+normal saline(100 m L)as *** scores were recorded using visual analogue scale(VAS)at baseline and 15 and 30 minutes after drug *** effects and the need for rescue medication(0.75 g/kg intravenous fentanyl)were also reported within 60 minutes of drug ***:before the infusion,the mean±SD VAS scores were 8.73±1.57 in group A and8.53±1.99 in group *** 15 minutes after drug administration,the mean±SD VAS scores were2.16±1.90 in group A vs.2.51±1.86 in group b;mean difference was–0.35,and 95%CI–1.15 to 0.45(P=0.38).At 30 minutes the mean±SD VAS scores were 1.66±1.59 in group A vs.2.14±1.79 in group b;mean difference was–0.48,and 95%CI–1.20 to 0.24(P=0.19).The mean pain scores in the two groups at 15 and 30 minutes demonstrated no significant ***:Paracetamol combined with low-dose morphine may be effective for pain management in patients with biliary colic.

关键词： biliary colic Morphine Paracetamol Visual analogue scale