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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 296-306页

作者： Mahmoud Reza SHAKARAMI ahad KAZEMI Center of Excellence for Power System Automation and Operation Department of Electrical EngineeringIran University of Science and Technology

This paper presents a procedure for designing a supplementary damping stabilizer for a static synchronous series compensator(SSSC) in multi-machine power *** objective is to shift the lightly damped inter-area modes toward the prescribed stability region.A lead-lag stabilizer is used to demonstrate this technique,in which a particular measure of stabilizer gain is considered as an objective *** of the problem for phase-lead and lag structures are *** objective function with the constraints is formed as a quadratic mathematical programming *** robust design,the parameters of the stabilizer are calculated under various operating *** types of SSSC-based stabilizer have been presented and *** results including eigenvalue analysis and the nonlinear simulations on the 4-and 50-machine power systems are pre-sented to show the effectiveness of the proposed method.

关键词： Inter-area oscillations Static synchronous series compensator(SSSC) Damping stabilizer Robust design Quadratic mathematical programming

Successful interferon desensitization in a patient with chronic hepatitis C infection

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World Journal of Gastroenterology 2009年第33期15卷 4196-4198页

作者： Seyed Alireza Taghavi ahad Eshraghian Gastroentero-hepatology Research Center of Shiraz University of Medical Science Nemazee Hospital

Treatment of hepatitis C, even when absolutely necessary, is almost impossible when interferon cannot be administered for any reason. We report a 65-year-old patient with chronic hepatitis C virus (HCV) infection and fibrosis, who was unable to receive interferon because of systemic hypersensitivity. The patient was desensitized successfully through gradual incremental exposure to interferon, and HCV infection was eradicated after a complete course of treatment, with no further allergic reactions. This case report that describes successful eradication of hepatitis C in a patient with advanced liver disease after desensitization to interferon revealed that desensitization may not necessarily damage the therapeutic efficacy of the drug.

关键词： Chronic hepatitis C Desensitization Drug hypersensitivity Interferon a2b Ribavirin

Micromechanics of breakage in sharp-edge particles using combined DEM and FEM

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Particuology 2008年第5期6卷 347-361页

作者： ahad Bagherzadeh-Khalkhali Ali Asghar Mirghasemi Soheil Mohammadi School of Civil Engineering University College of EngineeringUniversity of Tehran

By combining DEM （Discrete Element Method） and FEM （Finite Element Method）, a model is established to simulate the breakage of twodimensional sharp-edge particles, in which the simulated particles are assumed to have no cracks. Particles can, however, crush during different stages of the numerical analysis, if stress-based breakage criteria are fulfilled inside the particles. With this model, it is possible to study the influence of particle breakage on macro- and micro-mechanical behavior of simulated angular materials. Two series of tests, with and without breakable particles, are simulated under different confining pressures based on conditions of biaxial tests. The results, presented in terms of micromechanical behavior for different confining pressures, are compared with macroparameters. The influence of particle breakage on microstructure of sharp-edge materials is discussed and the related confining pressure effects are investigated. Breakage of particles in rockfill materials are shown to reduce the anisotropy coefficients of the samples and therefore their strength and dilation behaviors.

关键词： DEM FEM Particle breakage Rockfill Micromechanics Anisotropy Confining pressure

Mass transfer coefficient in the eductor liquid-liquid extraction column

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Chinese Journal of Chemical Engineering 2021年第12期34卷 27-35页

作者： Bahare Esmaeeli ahad Ghaemi Mansour Shirvani Mostafa Hosseinzadeh School of Chemical Petroleum and Gas EngineeringIran University of Science&TechnologyNarmakTehranIran

In this research gasoil desalting was investigated from mass transfer point of view in an eductor liquid–liquid extraction column(eductor-LLE device).Mass transfer characteristics of the eductor-LLE device were evaluated and an empirical correlation was obtained by dimensional analysis of the dispersed phase Sherwood *** Results showed that the overall mass transfer coefficient of the dispersed phase and extraction efficiency have been increased by increasing Sauter mean diameter(SMD)and decreasing the nozzle diameter from 2 to 1 mm,*** effects of Reynolds number(R_(e)),projection ratio(ratio of the distance between venturi throat and nozzle tip to venturi throat diameter,Rpr),venturi throat area to nozzle area ratio(R_(th-n))and two phases flow rates ratio(R_(Q))on the mass transfer coefficient(K)were *** to the results,K increase with increasing Re and RQ and also with decreasing Rpr and R_(th-n).Semi-empirical models of drop formation,rising and coalescence were compared with our proposed empirical *** was revealed that the present model provided a relatively good fitting for the mass transfer model of drop ***,experimental data were in better agreement with calculated data with AARE value of 0.085.

关键词： Gasoil desalting Liquid-liquid extraction Eductor-LLE device Mass transfer coefficient Extraction efficiency

Non-alcoholic fatty liver disease and thyroid dysfunction:A systematic review

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World Journal of Gastroenterology 2014年第25期20卷 8102-8109页

作者： ahad Eshraghian Alireza Hamidian Jahromi Department of Internal Medicine Namazi hospital Shiraz University of medical sciences PO Box 71345-1744 Shiraz Iran Department of Surgery Louisiana State University Health Sciences Center Shreveport LA 70803United States

Thyroid hormones are totally involved in the regulation of body weight, lipid metabolism, and insulin resistance. Therefore it is anticipated that thyroid hormones may have a role in the pathogenesis of non alcoholic fatty liver disease(NAFLD) and non alcoholic steatohepatitis(NASH). In this study, we reviewed the current literature on the association between thyroid dysfunction and NAFLD/NASH. A search for English language medical literature reporting an association between thyroid dysfunction and NAFLD/NASH in humans was conducted across PubMed, ISI Web of Science, and Scopus in August, 2013. Out of 140 studies initially identified through the search, 11 relevant articles were included in the final review. Thyroid dysfunctions in the form of overt or subclinical hypothyroidism are prevalent among patients with NAFLD/NASH. Hypothyroidism appears to be an independent risk factor for NAFLD/NASH in some studies; however, other newly published studies failed to find such anassociation. The results of the studies on the role of thyroid abnormalities in NAFLD/NASH are inconsistent, and further research is recommended to determine the relationship between hypothyroidism and NAFLD/NASH and the underlying mechanisms.

关键词： Non alcoholic fatty liver disease Thyroid dysfunction Hypothyroidism Non alcoholic steatohepatitis Risk factor Pathophysiology

Sublethal effects of imidacloprid and pymetrozine on population growth parameters of cabbage aphid, Brevicoryne brassicae on rapeseed, Brassica napus L.

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Insect Science 2007年第3期14卷 207-212页

作者： MOHAMMAD REZA LASHKARI ahad SAHRAGARD MOHAMMAD GHADAMYARI Department of Plant Protection College of Agriculture Guilan University Rasht Iran

Efficiency of imidacloprid and pymetrozine on population growth parameters of cabbage aphid, Brevicoryne brassicae L. （Homoptera： Aphididae） was determined using demographic toxicology by leaf dip method. At first, bioassay tests were performed. The LC50 value and confidence limit for imidacloprid and pymetrozine were 1.61 × 10^-5 mol/L （0.74 × 10^-5-2.66 × 10^-5） and 2.14 × 10^-4 mol/L （1.24 × 10^-4-3.40 × 10^-4）, respectively. To evaluate the sublethal effect of two insecticides on population growth parameters of cabbage aphid, LC30 concentrations of imidacloprid and pymetrozine were used at 5 mol/L and 30 mol/L. The experiments were carried out in a incubator at 20±1℃, 60% ± 5% RH and 16：8 （L：D） photoperiod on canola seedlings, Brassica napus L. var. ＇PF＇. Net fecundity rate decreased in both insecticide-treated populations. Intrinsic rates of increase （rm） were lower in imidacloprid and pymetrozine treatments than in controls. Intrinsic birth rates also decreased in treated populations. There was a relative increase in intrinsic death rates of treated populations. The mean generation times and doubling time were also lower in populations treated with insecticides than in controls. There was a considerable reduction in the average numbers of nymphs reproduced per female as compared with the control. The average longevity of female adults in the control was significantly different from those treated with imidacloprid and pymetrozine. However, there was no significant differences in aphid life-table parameters between the two insecticide-treated populations （P 〉 0.01）.

关键词： Brevicoryne brassicae canola imidacloprid life table pymetrozine

Experimental mass transfer coefficients in a pilot plant multistage column extractor

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Chinese Journal of Chemical Engineering 2016年第8期24卷 989-999页

作者： Mehdi Asadollahzadeh ahad Ghaemi Meisam Torab-Mostaedi Shahrokh Shahhosseini Department of Chemical Engineering Iran University of Science and Technology (IUST) Nuclear Fuel Cycle Research School Nuclear Science and Technology Research Institute

The volumetric overall mass transfer coefficients in a multistage column have been measured using axial dispersion model for toluene–acetone–water system. The effect of operating parameters on the volumetric overall mass transfer coefficients has been investigated for both mass transfer directions. The results show that the mass transfer performance is strongly dependent on rotor speed and mass transfer direction, although only slightly dependent on phase flow rates. In addition, empirical correlations to predict the overall mass transfer coefficients have been developed. The proposed correlations based on dimensionless numbers can be considered as a useful tool for the possible scale up of the multistage column extractor.

关键词： Multistage column Mass transfer coefficient Axial dispersion model Sherwood number

Impact of Hydroalcoholic Extract of Humulus Lupulus L. on Sperm Quality, Reproductive Organs and Hormones in Male Rats

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Chinese Journal of Integrative Medicine 2019年第7期25卷 529-535页

作者： Narges Karbalaei Najmeh Sadeghi Aliakbar Nekoeian ahad Malekzadeh Department of Physiology Physiology Research Center School of Medicine Medical Sciences University of Shiraz (71348-45794) Iran Department of Medical Physiology School of Medicine Jahrom University of Medical Sciences Jahrom (74148-44196) Iran Department of Pharmacology Pharmacology Research Center School of Medicine Medical Sciences University of Shiraz (71348-45794) Iran Department of Mathematics K.N. Toosi University of Technology Tehran (16315-1618) Iran

Objective: To investigate the impact of Humulus Lupulus L. hydroalcoholic extract on the body weights, reproductive organs, sperm quality and hormone levels in male rats. Methods: By simple random sampling method, seventy male Sprague-Dawley rats were randomly assigned to 7 groups including control group [distilled water, 1 mL/(kg·d)], Tween 80 group [25% Tween 80 solution, 1 mL/(kg·d)], olive oil group [olive oil, 1 mL/(kg·d)], diethyl stilbestrol(DES) group [DES, 100 μg/(kg·body weight)], H50, H150 and H450 [50, 150 and 400 mg/(kg·d) of Humulus Lupulus L extract, respectively]. The administration was performed via gavage once daily for 7 weeks. Body and reproductive organs weights including testes, seminal vesicles, epididymis and prostate were weighted and epididymal sperm quality were determined by digital balance. Blood samples were collected and serum free testosterone(T), luteinizing hormone(LH), follicle-stimulating hormone(FSH), and estrogen(E2) levels were measured by rat specific enzyme-linked immunosorbent assay. Results: The percentage increase in mean body weights of rats in the DES and H50, H150 and H450 groups decreased significantly compared to olive oil and Tween 80 groups(all P0.05). Conclusion: Humulus Lupulus L. extract significantly increased the seminal vesicle and testes weights and reduced the sperm motility.

关键词： sex organ phytoestrogen Humulus Lupulus L. sperm quality male rat

Possibilities of urban flood reduction through distributed-scale rainwater harvesting

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Water Science and Engineering 2020年第2期13卷 95-105页

作者： Aysha Akter ahad Hasan Tanim MdKamrul Islam Department of Civil Engineering Chittagong University of Engineering&Technology(CUET)Chittagong 4349Bangladesh Center for River Harbor and Landslide ResearchChittagong University of Engineering&Technology(CUET)Chittagong 4349Bangladesh Department of Urban and Regional Planning Chittagong University of Engineering&Technology(CUET)Chittagong 4349Bangladesh

Urban flooding in Chittagong City usually occurs during the monsoon season and a rainwater harvesting(RWH)system can be used as a remedial *** study examines the feasibility of rain barrel RWH system at a distributed scale within an urbanized area located in the northwestern part of Chittagong City that experiences flash flooding on a regular *** flood modeling,the storm water management model(SWMM)was employed with rain barrel low-impact development(LID)as a flood reduction *** Hydrologic Engineering Center's River Analysis System(HEC-RAS)inundation model was coupled with SWMM to observe the detailed and spatial extent of flood *** to SWMM simulated floods,the simulated inundation depth using remote sensing data and the HEC-RAS showed a reasonable match,i.e.,the correlation coefficients were found to be 0.70 and 0.98,***,using LID,i.e.,RWH,a reduction of 28.66%could be achieved for reducing flood ***,the study showed that 10%e60%imperviousness of the subcatchment area can yield a monthly RWH potential of 0.04e0.45 m3 from a square meter of rooftop *** model can be used for necessary decision making for flood reduction and to establish a distributed RWH system in the study area.

关键词： Low-impact development(LID) SWMM HEC-RAS Remote sensing Urban flooding Inundation depth

Assessment of assembly shape and geometric effects on amplification of shear waves using discrete element method

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Particuology 2022年第7期20卷 85-99页

作者： Leila Karbor Seyed Majdeddin Mir Mohammad Hosseini ahad Bagherzadeh Khalkhali Civil and Environmental Engineering Faculty Amirkabir University of TechnologyTehranIran Civil Engineering Faculty Science and Research BranchIslamic Azad UniversityTehranIran

The discrete element method(DEM)is a capable tool used to simulate shear wave propagation in granular assemblies for many *** have studied assembly shapes such as rectangles(in 2D simulations)or cylinders and cubes(in 3D simulations).This paper aimed to qualify the effect of assembly shape on the shear wave propagation and maximum amplification in the vertical plane(horizontal and vertical directions)caused by this *** this end,shear wave propagations in different assembly shapes such as rectangle,trapezium,and triangle with rigid boundary conditions were simulated.A sine wave pulse was applied with a point source by moving a particle as the transmitter *** evaluate the shear wave velocity of the assemblies,the transmitter and receiver particles were *** the simulations were performed with 2D DEM which is a useful tool to determine the amount and location of the maximum amplification factor of the assembly in both horizontal and vertical *** advantage of this study was assessing the effect of parameters such as input wave frequency,assembly height,shape,and aspect ratios on the amplification of the input waves.

关键词： Wave propagation Granular assembly DEM Assembly shape Shear wave