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Modeling of D-STATCOM in distribution systems load flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1532-1542页

作者： HOSSEINI Mehdi SHAYANFAR heidar ali FOTUHI-FIRUZABAD Mahmud Center of Excellence for Power System Automation and Operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Technical Engineering of Babol University of Mazandaran Shariati Ave. 47144 P. O. Box 484 Babol Iran Center of Excellence for Power System Automation and Operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Department of Electrical Engineering Sharif University of Technology Azadi Ave. 11365-9363 Tehran Iran

This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems.

关键词： Distribution system D-STATCOM Voltage compensation Load flow

Stability Analysis and Performance Evaluation of Delayed Bilateral Telerobotic Systems over a Lossy Communication Channel

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Journal of Systems Science & Complexity 2021年第1期34卷 157-179页

作者： BAKHSHI ali ALFI alireza TALEBI heidar ali SOURATGAR Amir Aboulfazl YOUSEFI Mahdi Faculty of Electrical and Robotic Engineering Shahrood University of TechnologyShahrood 36199-95161Iran Power Plants Control Systems Technology Development Plan Department of monitoring and ControlNiroo Research InstituteTehran 14665-517Iran Real-Time and Robotics system Laboratory Faculty of Electrical EngineeringAmirkabir University of TechnologyHafez AvenueTehran 15914Iran Electrical and Computer Engineering Department The University of British Columbia2385East MallVan couverBC V6T 1Z4Canada

The focus of this paper is to address a novel control technique for stability and transparency analysis of bilateral telerobotic systems in the presence of data loss and time delay in the communication channel. Different control strategies have been reported to compensate the effects of time delay in the communication channel;however, most of them result in poor performance under data loss. First, a model for data loss is proposed using a finite series representation of a set of periodic continuous *** improve the performance and data reconstruction, a holder circuits is also introduced. The passivity of the overall system is provided via the wave variable technique based on the proposed model for the data loss. The stability analysis of the system is then derived using the Lyapunov theorem under the time delay and the data loss. Finally, experimental results are given to illustrate the capability of the proposed control technique.

关键词： Lossy channel passivity stability telerobotic transparency

Mechanistic, Energetic and Structural Aspects of the Adsorption of Carmustine on the Functionalized Carbon Nanotubes

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Chinese Journal of Structural Chemistry 2017年第10期36卷 1639-1646页

作者： KHORRAM Rabeeh MORSali ali RAISSI heidar HAKIMI Mohammad BEYRAMABADI S. ali Chemistry Department Payame Noor University 19395-4697 Tehran I. R. of IRAN Department of Chemistry Mashhad Branch Islamic Azad University Mashhad Iran & Research Centerfor Animal Development Applied Biology Mashhad Branch Islamic Azad University Mashhad 917568 Iran Chemistry Department University of Birjand Birjand Iran

Using density functional theory, noncovalent interactions and two mechanisms of covalent functionalization of drug carmustine with functionalized carbon nanotube（CNT） have been investigated. Quantum molecular descriptors of noncovalent configurations were studied. It was specified that binding of drug carmustine with functionalized CNT is thermodynamically suitable. NTCOOH and NTCOCl can bond to the NH group of carmustine through OH（COOH mechanism） and Cl（COCl mechanism） groups, respectively. The activation energies, activation enthalpies and activation Gibbs free energies of two pathways were calculated and compared with each other. The activation parameters related to COOH mechanism are higher than those related to COCl mechanism, and therefore COCl mechanism is suitable for covalent functionalization. COOH functionalized CNT（NTCOOH） has more binding energy than COCl functionalized CNT（NTCOCl） and can act as a favorable system for carmustine drug delivery within biological and chemical systems（noncovalent）. These results could be generalized to other similar drugs.

关键词： carmustine, covalent and noncovalent adsorption, functionalized carbon nanotubes, quantum molecular descriptors, reaction mechanisms

Experimental Investigation and Modeling of Activity Coefficient at Infinite Dilution of Solutes Using Dicationic Solvent Based on Pyrrolidinium as a New Stationary Phase in Gas Chromatography

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American Journal of Analytical Chemistry 2018年第4期9卷 257-271页

作者： ali Yahyaee Mina Nazifi Mohsen Kianpour Kurosh Tabar heidar School of Mechanical Engineering Iran University of Science and Technology (IUST) Tehran Iran Chemistry and Chemical Engineering Research Center of Iran Tehran Iran Iranian Catalyst Development (ICD) Tehran Iran

Activity coefficients at infinite dilution, γ ∞ i, were calculated for 12 solutes, with organic solutes including linear alcohols (methanol, ethanol, propanol), linear alkanes (heptane, octane), benzene, toluene, cyclohexane, 1, 2-dichloroethane, trichloroethylene, acetonitrile and carbon tetrachloride. The values of γ ∞ i were determined via either thermodynamic or artificial neural network modelling at different temperatures. A comparison between extracted results from these two methods confirmed that experimental and predicted results are roughly the same. The accuracy of predicted results proves this model is fully compatible with a wide range of solutes, and it can readily be used as an alternative to conventional gas-liquid chromatography for the measurements of activity coefficient at infinite dilution.

关键词： Gas Chromatography Ionic Liquid Activity Coefficients at Infinite Dilution Artificial Neural Network (ANN) Thermodynamic Modeling

Interferon-λ polymorphisms and response to pegylated interferon in Iranian hepatitis C patients

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World Journal of Gastroenterology 2015年第29期21卷 8935-8942页

作者： Arghavan Haj-sheykholeslami Maryam Keshvari heidar Sharafi ali Pouryasin Khalil Hemmati Fatemeh Mohammadzadehparjikolaei The Liver Pancreatic and Biliary Diseases Research Center Digestive Diseases Research Institute Tehran University of Medical Sciences Blood Transfusion Research Center High Institute for Research and Education in Transfusion Medicine Middle East Liver Disease Center Armin Pathobiology Laboratory

AIM: To evaluate the efficacy of pegylated interferon in Iranian chronic hepatitis C patients in relation to interferon-λ(IFNL) polymorphisms. METHODS: This study enrolled patients with chronic hepatitis C referred to the Tehran Blood Transfusion Hepatitis Clinic in 2011. Patients were included in the study if they had no concomitant hepatic illness, were negative for human immunodeficiency virus antibodies, and had no prior history of treatment with any type ofpegylated interferon. Patients were treated with 180 μg pegylated interferon alpha-2a(Pegaferon®) weekly and 800-1200 mg ribavirin daily for 24 or 48 wk depending on weight and hepatitis C virus(HCV) genotype. Blood samples were collected from patients to obtain DNA for determination of IFNL rs12979860 and rs8099917 polymorphisms. The virologic response in patients was then evaluated and compared between the different IFNL ***: A total of 152 patients with a mean age of 41.9 ± 10.0 years were included in the study, of which 141/152 were men(92.8%). The most frequent HCV genotype was type-1, infecting 93/152(61.2%) patients. Sustained virologic response(SVR) was achieved in 81.9% of patients with HCV genotype-1 and 91.1% of patients with HCV genotype-3. Treatment success was achieved in 91.2%(52/57) of patients with the IFNL rs12979860 CC genotype and 82.1%(78/95) in those with other genotypes. Similar treatment response rates were also observed in patients with rs8099917 TT(39/45; 86.7%) and non-TT(61/68; 89.7%) genotypes. Univariate analyses identified the following factors which influenced treatment response for inclusion in a multivariate analysis: age, HCV RNA level, stage of liver fibrosis, rs12979860 CC genotype, and aspartate transaminase level. A logistic regression analysis revealed that only the rs12979860 CC genotype was significantly associated with achievement of SVR(OR = 6.2; 95%CI: 1.2-31.9; P = 0.03).CONCLUSION: The rs12979860 CC genotype was associated with SVR in patients

关键词： Chronic hepatitis C Pegylated interferon rs12979860 rs8099917 Sustained virologic response