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China Ocean Engineering 2014年第6期28卷 843-856页

作者： Mansour ATAEI aghil yousefi-koma Center of Advanced Systems & Technologies Faculty of Mechanical EngineeringCollege of Engineering University of Tehran

The present paper introduces a three-dimensional guidance system developed for a miniature Autonomous Underwater Vehicle（AUV）. The guidance system determines the best trajectory for the vehicle based on target behavior and vehicle capabilities. The dynamic model of this novel AUV is derived based on its special characteristics such as the horizontal posture and the independent diving mechanism. To design the guidance strategy, the main idea is to select the desired depth, presumed proportional to the horizontal distance of the AUV and the target. By connecting the two with a straight line, this strategy helps the AUV move in a trajectory sufficiently close to this line. The adjacency of the trajectory to the line leads to reasonably short travelling distances and avoids unsafe areas. Autopilots are designed using sliding mode controller. Two different engagement geometries are considered to evaluate the strategy＇s performance： stationary target and moving target. The simulation results show that the strategy can provide sufficiently fast and smooth trajectories in both target situations.

关键词： Autonomous Underwater Vehicle(AUV) Three-Dimensional(3D) guidance system Line-of-Sight(LOS) strategy autopilot sliding mode controller

Experimental investigation of shock-buffet criteria on a pitching airfoil

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Chinese Journal of Aeronautics 2022年第7期35卷 179-191页

作者： Mehran MASDARI aghil ZEINALZADEH Mohammad Ali ABDI Mohammad Reza SOLTANI Faculty of New Sciences and Technologies University of TehranTehran ***Iran Department of Aerospace Engineering Sharif University of TechnologyTehran 11365-11155Iran Department of Aeronautical and Astronomical Engineering University of WashingtonSeattleWAUSA

An experimental investigation of the shock-buffet phenomenon subject to unsteady pitching supercritical airfoil around its quarter chord has been conducted in a transonic wind *** model was equipped with pressure taps connected to the fast response *** were conducted at different free-stream Mach number from 0.61 *** principle goal of this investigation was to experimentally discuss the shock-buffet criterion over a SC(2)-0410 supercritical pitching related to the hysteresis loops of total drag and trailing edge pressure,the behaviour of the shock wave foot location,the pressure distribution over the upper surface,and by implementing the wavelet analysis of the normal *** ensure capturing the buffet phenomenon by utilizing these criteria,a pressure port has been drilled exactly at the trailing edge of the airfoil where its output was used to detect the buffet phenomenon for different *** representation of the flow using the shadow graph flow visualization technique for different test cases is further used to illustrate the unsteady shock wave motion.A comparative analysis of experimental measurements shows that the conducted criteria confirm each other when the buffet phenomenon occurs at the position of the oscillating cycle.

关键词： Airfoil Buffeting Experimental analysis Hysteresis loops Pitching motion Shock wave Wavelet analysis

Accurate 3D Thermal Network Development for Direct-drive Outer-rotor Hybrid-PM Flux-switching Generator

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Chinese Journal of Electrical Engineering 2024年第2期10卷 80-92页

作者： Ali Zarghani Mohammad Farahzadi aghil Ghaheri Karim Abbaszadeh Faculty of Electrical Engineering Shahid Beheshti UniversityTehran ***Iran Faculty of Electrical Engineering University of Science and CultureTehran ***Iran Department of Electrical Engineering K.N.Toosi University of TechnologyTehran ***Iran

Heat and thermal problems are major obstacles to achieving high power density in compact permanent magnet(PM)***,a comprehensive,accurate,and rapid temperature rise estimation method is required for novel electric machines to ensure safe and reliable operations.A unique three-dimensional(3D)lumped parameter thermal network(LPTN)is presented for accurate thermal modeling of a newly developed outer-rotor hybrid-PM flux switching generator(OR-HPMFSG)for direct-drive ***,the losses of the OR-HPMFSG are calculated using 3D finite element analysis(FEA).Subsequently,all machine components considering the thermal contact resistance,anisotropic thermal conductivity of materials,and various heat flow paths are comprehensively modeled based on the thermal *** the proposed 3-D LPTN,internal nodes are considered to predict the average temperature as well as the hot spots of all active and passive *** measurements are performed on a prototype OR-HPMFSG to validate the efficiency of the 3-D LPTN.A comparison of the results at various operating points between the developed 3-D LPTN,experimental test,and FEA indicates that the 3-D LPTN quickly approximates the hotspot and mean temperature of all components under both transient and steady states with high accuracy.

关键词： Direct-drive wind turbine hybrid-PM flux switching generator lumped parameter thermal network temperature estimation 3D thermal modeling

A natural dye in water-based drilling fluids: Swelling inhibitive characteristic and side effects

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Petroleum 2017年第3期3卷 355-366页

作者： aghil Moslemizadeh Seyed Reza Shadizadeh Department of Petroleum Engineering Ahwaz Faculty of Petroleum EngineeringPetroleum University of TechnologyP.O.Box 63134AhwazIran Department of Petroleum Engineering Abadan Faculty of Petroleum EngineeringPetroleum University of TechnologyAbadanIran

The development of eco-friendly shale inhibitors is still an area which has attracted a lot of attention in the drilling *** extract is a natural dye which has recently shown considerable inhibition and weak deflocculation properties in clay-water *** study aims to investigate swelling inhibitive feature and side effects of Henna extract in water-based drilling fluids(WBDFs).It was carried out through extensive experiments including adsorption measurements on shale by batch equilibrium,inhibition evaluation by dynamic linear swelling and cuttings dispersion,wettability alteration via contact angle measurements,compatibility by rheological properties determinations and fluid loss measurements,and *** in natural pH and adjusted pH to 9,Linear adsorption model was more suitable for anticipating the adsorption behavior of Henna extract on the given shale *** results of the linear swelling and cuttings dispersion tests demonstrated that Henna extract in drilling fluid formulations diminished the swelling and dispersion characteristics of the addressed shale ***,contact angle measurements showed that Henna extract expanded the hydrophobicity of shale formations,preventing and promoting water adsorption and shale stability *** issue definitely introduces wettability alteration as a mechanism for shale stability by Henna *** determinations additionally uncovered that Henna extract is compatible with common WBDFs *** indicated by the lubricity tests,Henna extract enhanced the lubricity of WBDFs,a finding which can be of an incredible significance in directional *** others,advantages such as environmental friendliness,low cost,accessibility,and the counter corrosion property make the applicability of Henna extract in WBDFs profoundly suitable.

关键词： Shale inhibitors Natural dye Water-based drilling fluids(WBDFs) Adsorption Wettability Compatibility Lubricity

An advanced cost-efficient IoT method for stroke rehabilitation using smart gloves

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Nanotechnology and Precision Engineering 2023年第4期6卷 40-54页

作者： A.Arivarasi D.Thiripurasundari A.Arockia Selvakumar Bhuvan Kumaar T.aghil S.Rahul Ramani Kannan Vellore Institute of Technology ChennaiIndia Universiti Tecknologi Petronas Kuala LumpurMalaysia

Stroke represents a severe,widespread,and widely acknowledged health crisis on both national and international *** is one of the most prevalent life-threatening *** impressive advances in treating stroke,in addition to a need for effective patient care services,many sufferers still rely solely on physical *** present paper describes and explains the use of a newly designed gadget for stroke survivors who cannot move their *** is a sophisticated mobile device that enables stroke patients to regain their muscle memory and thus their ability to perform repetitive actions by continuing to tighten and stretch their muscles without the intervention of a *** methodology is used to encourage patients to become involved in the process of *** device also has sensors that take information and transmit it to an app through an ESP32 *** enables physicians to view glove usage information remotely and keep track of an individual patient’s *** between app and glove is facilitated by a broker in the Amazon Web Service *** the robotic glove presented here,the recovery rate is found to be 90.23%over four weeks’duration,which represents a significant improvement compared with existing hospital-based rehabilitation techniques.

关键词： Stroke rehabilitation Smart glove ESP32 AWS cloud

White spot syndrome virus inactivation study by using gamma irradiation

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Chinese Journal of Oceanology and Limnology 2014年第5期32卷 1024-1028页

作者： Marzieh HEIDAREH Farahnaz Motamedi SEDEH Mehdi SOLTANI Saeed RAJABIFAR Mohammad AFSHARNASAB aghil DASHTIANNASAB Nuclear Science and Technology Research Institute Veterinary Faculty University of Tehran Iran Fisheries Research Institute

The present study was conducted to investigate the effect of gamma irradiation on white spot syndrome virus （WS SV）. White spot syndrome virus is a pathogen of major economic importance in cultured penaeid shrimp industries. White spot disease can cause mortalities reaching 100% within 3-10 days of gross signs appearing. During the period of culture, immunostimulant agents and vaccines may provide potential methods to protect shrimps from opportunistic and pathogenic microrganisms. In this study, firstly, WSSV was isolated from infected shrimp and then multiplied in crayfish. WSSV was purified from the infected crayfish haemolymph by sucrose gradient and confirmed by transmission electron microscopy. In vivo virus titration was performed in shrimp, Penaeus semisulcatus. The LD50 of live virus stock was calculated 1054/mL. Shrimp post-larvae （1-2 g） were treated with gamma-irradiated （different doses） WSSV （10^o to 10^-4 dilutions） for a period of 10 days. The dose/survival curve for irradiated and un-irradiated WSSV was drawn; the optimum dose range for inactivation of WSSV and unaltered antigenicity was obtained 14- 15 kGy. This preliminary information suggests that shrimp appear to benefit from treatment with gamma- irradiated WSSV especially at 14-15 KGy.

关键词： white spot syndrome virus (WSSV) gamma irradiation titration LD50

Columnar structure of human telomeric chromatin

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四川生理科学杂志 2022年第9期44卷 1672-1672页

作者： aghil Soman School of Biological Sciences Nanyang Technological University Singapore Singapore NTU Institute of Structural Biology Nanyang Technological University Singapore Singapore Singapore Centre for Environmental Sciences Engineering (SCELSE) Nanyang Technological University Singapore Singapore Huygens-Kamerlingh Onnes Laboratory Leiden University Leiden The Netherlands Medical Research Council Laboratory of Molecular Biology Cambridge UK

Telomeres,the ends of eukaryotic chromosomes,play pivotal parts in ageing and cancer and are targets of DNA damage and the DNA damage *** is known about the structure of telomeric chromatin at the molecular *** we used negative stain electron microscopy and single-molecule magnetic tweezers to characterize 3-kbp-long telomeric chromatin *** also obtained the cryogenic electron microscopy structure of the condensed telomeric tetranucleosome and its dinucleosome *** structure displayed close stacking of nucleosomes with a columnar arrangement,and an unusually short nucleosome repeat length that comprised about 132 bp DNA wound in a continuous superhelix around histone *** columnar structure is primarily stabilized by the H2A carboxy-terminal and histone amino-terminal tails in a synergistic *** columnar conformation results in exposure of the DNA helix,which may make it susceptible to both DNA damage and the DNA damage *** conformation also exists in an alternative open state,in which one nucleosome is unstacked and flipped out,which exposes the acidic patch of the histone *** structural features revealed in this work suggest mechanisms by which protein factors involved in telomere maintenance can access telomeric chromatin in its compact form.

关键词： structure damage arrangement

Radon CLF:A Novel Approach for Skew Detection Using Radon Transform

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Computer Systems Science & Engineering 2023年第10期47卷 675-697页

作者： Yuhang Chen Mahdi Bahaghighat aghil Esmaeili Kelishomi Jingyi Du Laboratory for Control Engineering Xi’an University of Science&TechnologyXi’anChina Computer Engineering Department Imam Khomeini International UniversityQazvinIran MOE Key Laboratory for Intelligent and Network Security Xi’an Jiaotong UniversityXi’anChina

In the digital world,a wide range of handwritten and printed documents should be converted to digital format using a variety of tools,including mobile phones and ***,this is not an optimal procedure,and the entire document image might be *** conversion effects due to noise,motion blur,and skew distortion can lead to significant impact on the accuracy and effectiveness of document image segmentation and analysis in Optical Character Recognition(OCR)*** Document Image Analysis Systems(DIAS),skew estimation of images is a crucial *** this paper,a novel,fast,and reliable skew detection algorithm based on the Radon Transform and Curve Length Fitness Function(CLF),so-called Radon CLF,was *** Radon CLF model aims to take advantage of the properties of Radon *** Radon CLF explores the dominating angle more effectively for a 1D signal than it does for a 2D input image due to an innovative fitness function formulation for a projected signal of the Radon *** significant performance indicators,including Mean Square Error(MSE),Mean Absolute Error(MAE),Peak Signal-to-Noise Ratio(PSNR),Structural Similarity Measure(SSIM),Accuracy,and run-time,were taken into consideration when assessing the performance of our *** addition,a new dataset named DSI5000 was constructed to assess the accuracy of the CLF *** two-dimensional image signal and the Radon space have been used in our simulations to compare the noise *** results show that the proposed method is more effective than other approaches already in use,with an accuracy of roughly 99.87%and a run-time of 0.048(s).The introduced model is far more accurate and timeefficient than current approaches in detecting image skew.

关键词： Document image analysis skew detection Radon transform pattern recognition

Characterization and frequency of antibiotic resistance related to membrane porin and efflux pump genes among Acinetobacter baumannii strains obtained from burn patients in Tehran, Iran

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Journal of Acute Disease 2019年第2期8卷 63-66页

作者： Majid Noori Behzad Mohsenzadeh aghil Bahramian Fatemeh Shahi Habibollah Mirzaei Saeed Khoshnood Department of Infectious Diseases Faculty of MedicineArmy University of Medical SciencesTehranIran Golestan Hospital Army University of Medical SciencesTehranIran Department of Microbiology school of MedicineShahid Beheshti University of Medical sciencesTehranIran Department of Microbiology Faculty of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran Student Research Committee Ahvaz Jundishapur University of Medical SciencesAhvazIran Hepatitis Research Center Lorestan University of Medical SciencesKhorramabadIRIran

Objective: To explore the characterization and frequency of antibiotic resistance related to membrane porin and efflux pump genes among Acinetobacter baumannii (A. baumannii) strains obtained from burn patients in Tehran, Iran. Methods: In this cross-sectional descriptive study, 100 strains of A. baumannii isolated from burn patients visiting teaching hospitals of Tehran were collected from January 2016 to November 2017. After A. baumannii strains were confirmed, antimicrobial susceptibility testing was done via Kirby-Bauer disc diffusion method according to the Clinical and Laboratory Standards Institute guidelines. PCR amplification was performed for detection of β-lactamase adeR, OprD, adeS genes among A. baumannii strains. Results: All isolates (100%) were resistant to ceftazidime, cefotaxime, cefepime, ciprofloxacin, and piperacillin, and most isolates indicated high resistance (95%-97%) to meropenem, imipenem, gentamicin, ceftriaxone, trimethoprim-sulfamethoxazole, piperacillin-tazobactam, amikacin, and tetracycline. The most effective antibiotic against A. baumannii isolates was colistin (97% sensitivity), followed by tigecycline. The frequency of OprD, adeS, and adeR genes were 98%, 91%, and 77%, respectively. Conclusions: This study shows that the majority of A. baumannii isolates are highly resistant to the antibiotics most commonly used in burn patients. Also, high distribution of OprD and adeRS genes may be responsible for the observed resistances among A. baumannii isolates that demonstrate the possible role of both efflux pumps in simultaneous of carbapenemase production during antibiotic resistance.

关键词： Acinetobacter baumannii Multidrug resistance Burn Efflux pump genes