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Seismic isolation effect of lined circular tunnels with damping treatments

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Earthquake Engineering and Engineering Vibration 2008年第3期7卷 305-319页

作者： Seyyed M. Hasheminejad amir k. Miri Acoustics Research Laboratory Department of Mechanical Engineering Iran University of Science and Technology Narmak Tehran 16844 Iran

The Havriliak-Negami model for dynamic viscoelastic material behavior and Biot＇s theory of poroelasticity are employed to develop an exact solution for three-dimensional scattering effect of harmonic plane P-SV waves from a circular cavity lined with a multilayered fluid-filled shell of infinite length containing viscoelastic damping materials and embedded within a fluid-saturated permeable surrounding soil medium. The analytical results are illustrated with numerical examples where the effects of liner/coating structural arrangement, viscoelastic material properties, liner-soil interface bonding condition, seismic excitation frequency, and angle of incidence on the induced dynamic stress concentrations are evaluated and discussed to obtain representative values of the parameters that characterize the system. It is demonstrated that incorporating viscoelastic damping materials with a low shear modulus in the constrained layer configuration is an efficient means of enhancing the overall seismic isolation performance, especially for near-normally incident seismic shear waves where the amplitudes of induced dynamic stresses may be reduced by up to one-third of those without isolation in a relatively wide frequency range. Some additional cases are considered and good agreements with solutions available in the literature are obtained.

关键词： underground tunnel permeable soil seismic wave scattering flee/constrained layer damping

Closure to“Discussion on‘Optimum placement and characteristics of velocity-dependent dampers under seismic excitation' by SA Mousavi and Ak Ghorbani-Tanha”by Izuru Takewaki

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Earthquake Engineering and Engineering Vibration 2013年第4期12卷 681-682页

作者： Seyed Amin Mousavi amir k.Ghorbani-Tanha School of Civil Engineering College of EngineeringUniversity of Tehran

The authors would like to thank the discusser for his considerations and comments. The discusser believes that some of the derived formulations need to be referred to his previously published works and also some relat... 详细信息

关键词： Optimum placement and characteristics of velocity-dependent dampers under seismic excitation by SA Mousavi and Ak Ghorbani-Tanha Closure to

Application of artificial neural networks in optimal tuning of tuned mass dampers implemented in high-rise buildings subjected to wind load

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 903-915页

作者： Meysam Ramezani Akbar Bathaei amir k.Ghorbani-Tanha School of Civil Engineering College of Engineering University of Tehran

High-rise buildings are usually considered as flexible structures with low inherent damping. Therefore, these kinds of buildings are susceptible to wind-induced vibration. Tuned Mass Damper（TMD） can be used as an effective device to mitigate excessive vibrations. In this study, Artificial Neural Networks is used to find optimal mechanical properties of TMD for high-rise buildings subjected to wind load. The patterns obtained from structural analysis of different multi degree of freedom（MDF） systems are used for training neural networks. In order to obtain these patterns, structural models of some systems with 10 to 80 degrees-of-freedoms are built in MATLAB/SIMULINk program. Finally, the optimal properties of TMD are determined based on the objective of maximum displacement response reduction. The Auto-Regressive model is used to simulate the wind load. In this way, the uncertainties related to wind loading can be taken into account in neural network’s outputs. After training the neural network, it becomes possible to set the frequency and TMD mass ratio as inputs and get the optimal TMD frequency and damping ratio as outputs. As a case study, a benchmark 76-story office building is considered and the presented procedure is used to obtain optimal characteristics of the TMD for the building.

关键词： artificial neural networks tuned mass damper wind load auto-regressive model optimal frequency anddamping

Optimum placement and characteristics of velocity-dependent dampers under seismic excitation

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 403-414页

作者： Seyed Amin Mousavi amir k.Ghorbani-Tanha R&D Department Sabok Sazan Sarie Engineering Company School of Civil Engineering College of EngineeringUniversity of Tehran

In this study, through novel drift-based equations of motion in the frequency domain, optimum placement and characteristics of linear velocity-dependent dampers are investigated. In this study, the sum of the square of the absolute values of transfer matrix elements for interstory drifts is considered as the optimization index. Optimum placement and characteristics of dampers are simultaneously obtained by minimizing the optimization index through an incremental procedure. In each step of the procedure, a predefined value is considered as the damper characteristic. The optimum story for this increment is selected such that it leads to a minimum value for the optimization index. The procedure is repeated for the next increments until the optimization index meets its target value, which is obtained according to the desired damping ratio for the overall structure. In other words, the desired overall damping ratio is the input to the proposed procedure, and the optimal placement and characteristics of the dampers are its output. It is observed that the optimal placement of a velocitydependent damper depends on the damping coefficient of the added damper, frequency of the excitation, and distribution of the mass, stiffness, and inherent damping of the main structure.

关键词： passive control velocity-dependent damper optimum placement optimum damping transfer matrix storydamping coefficient

Bacteriophage Biocontrol Rescues Mice Bacteremic of Clinically Isolated Mastitis from Dairy Cows Associated with Methicillin-Resistant <i>Staphyloccocus aureus</i>

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Advances in Microbiology 2015年第6期5卷 383-403页

作者： Atheer A. Aldoori Elaph F. Mahdii amir k. Abbas Sabah A. A. Jassim Department of Microbiology College of Veterinary Medicine University of Baghdad Baghdad Iraq Food Pollution Research Centre Ministry of Science and Technology Baghdad Iraq Applied Bio Research Inc. Windsor Canada

Methicillin-resistant Staphylococcus aureus (MRSA) is among the most alarming pathogens affecting both humans and the global bovine industry. The current control measures in hospitals and on farms for MRSA have proven to be inadequate leaving a need for new rapid control methods to curb MRSA infections in situ. New control measures for bacterial infection are widely sought, with particular interest in the applications for bacteriophages (phages) as a biocontrol or therapeutic agent. The current study uses a wild highly lytic phage isolated from cow’s milk taken from three farms in Baghdad, Iraq. The resulting phage was able to rescue 100% of the mice from a median lethal dose (LD50) or (1 × 108 CFU mL-1 per mouse) for MRSA wild isolates achieved when the phage: bacteria ratio was 100:1. Even when treatment was delayed for 6 h post lethal infection, to the point where all mice were moribund, 80% of them were rescued by a single injection of this phage preparation. Based on the current results, a comprehensive study is needed to guide further research on the MRSA phage as a biocontrol for MRSA mastitis in dairy cows to replace or reduce the use of antibiotics in animal husbandry.

关键词： Bacteriophages Phage Biocontrol Methicillin-Resistant Staphyloccocus aureus MRSA Mastitis Antibiotics

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基于独立脉冲转向系统车辆稳定性控制

湖南大学学报（自然科学版） 2017年第10期44卷 25-32页

作者：张宝珍谢晖黄晶阿米尔湖南大学汽车车身先进设计制造国家重点实验室湖南长沙410082 滑铁卢大学机电工程学院加拿大滑铁卢N2L3G1

为了提高车辆操纵稳定性,本文集成独立转向和主动脉冲转向提出了一种主动后轮独立脉冲转向(ARIPS)控制策略,并对此进行理论分析和试验研究.通过建立ARIPS系统仿真动力学模型,研究此系统的运行对悬架性能的影响并分析不同转向脉冲控制参... 详细信息

为了提高车辆操纵稳定性,本文集成独立转向和主动脉冲转向提出了一种主动后轮独立脉冲转向(ARIPS)控制策略,并对此进行理论分析和试验研究.通过建立ARIPS系统仿真动力学模型,研究此系统的运行对悬架性能的影响并分析不同转向脉冲控制参数对车辆稳定性的影响.依据仿真分析和频率分析方法确定最优脉冲参数.设计ARIPS控制器及脉冲转角分配模块,基于CarSim和Simulink进行联合仿真分析,验证ARIPS的控制性能.研制并安装主动脉冲转向系统,基于试验Lexus车辆进行整车试验研究,验证ARIPS系统的实用性.仿真和试验结果表明:验证了ARIPS系统的可行性和经济性,ARIPS控制能有效提高车辆的操纵稳定性,比主动后轮转向(ARS)和主动后轮脉冲转向(ARPS)具有更好的控制效果,对改进四轮转向(4WS)系统的性能提供了一个新的研究方向和试验基础.

关键词：车辆动力学四轮转向独立转向脉冲控制稳定性整车试验

Data-driven failure diagnosis in transmission protection system with multiple events and data anomalies

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 767-778页

作者： amir GHOLAMI Anurag k.SRIVASTAVA Shikhar PANDEY Washington State University PullmanUSA

To guarantee a reliable power supply,the expected operation of all the components in the power system is *** protection system is primarily responsible of isolating the faulty section from the healthy part for the *** in protection devices can result in multiple conflicting alarms at the power grid operation center and complex event analysis to manually find the root cause of the observed system *** not handled in time,it may lead to the propagation of the faults/failures to the adjacent transmission lines and *** availability of the synchronized measurements from phasor measurement units(PMUs),real-time system monitoring and automated failure diagnosis are *** multiple adverse events and possible data anomalies,the complexity of the problem will be *** this paper,a PMUbased algorithm is presented and discussed to detect the root cause of the failure in transmission protection system based on the observed state,*** line tripping andbreaker *** failure diagnosis algorithm is further enhanced to come up with the fully functional version of the failure diagnosis tool,which is tailored for the cases in which the PMU anomalies are *** the developed algorithm,the validity of the PMU data is ***,such causes as communication errors or cyber-attacks might lead to the PMU data *** issue is welladdressed in this paper and some major types of anomaly detection methods suitable for PMU data are *** show that the ensemble approach has some distinct advantages in data anomaly detection compared to the previously used standalone ***,the enhanced failure diagnosis method is developed to clean the inaccurate data in case of the anomaly in measured voltage ***,both original and enhanced versions of the tool are tested on 96-bus test system using the real-time OPAL-RT *** results show the accuracy of the enhanced tool and

关键词： Failure diagnosis Transmission protection system Protection mis-operation Phasor measurement unit(PMU) Data anomaly and cleaning Ensemble method

Automatic fuzzy-DBSCAN algorithm for morphological and overlapping datasets

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1245-1253页

作者： YELGHI Aref kÖSE Cemal YELGHI Asef SHAHkAR amir Department of Computer Engineering Avrasya UniversityTrabzon 61250Turkey Department of Computer Engineering Karadeniz Technical UniversityTrabzon 61080Turkey Department of Business Administration Gazi UniversityAnkara 06560Turkey Civil Engineering Department Karadeniz Technical UniversityTrabzon 61080Turkey

Clustering is one of the unsupervised learning *** is a procedure which partitions data objects into *** algorithms could not overcome the problems of morphology,overlapping and the large number of clusters at the same *** scientific communities have used the clustering algorithm from the perspective of density,which is one of the best methods in *** study proposes a density-based spatial clustering of applications with noise(DBSCAN)algorithm based on the selected high-density areas by automatic fuzzy-DBSCAN(AFD)which works with the initialization of two ***,by using fuzzy and DBSCAN features,is modeled by the selection of high-density areas and generates two parameters for merging and separating *** two generated parameters provide a state of sub-cluster rules in the Cartesian coordinate system for the *** model overcomes the problems of clustering such as morphology,overlapping,and the number of clusters in a dataset *** the experiments,all algorithms are performed on eight data sets with 30 times of *** of them are related to overlapping real datasets and the rest are morphologic and synthetic *** is demonstrated that the AFD algorithm outperforms other recently developed clustering algorithms.

关键词： clustering density-based spatial clustering of applications with noise(DBSCAN) fuzzy overlapping data mining

CFD simulation of impeller shape effect on quality of mixing in two-phase gas–liquid agitated vessel

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Chinese Journal of Chemical Engineering 2020年第11期28卷 2733-2745页

作者： amir Heidari Process Simulation and Modeling Laboratory(PSMlab) Faculty of ChemicalPetroleum and Gas EngineeringSemnan UniversitySemnan ***Iran

Mixing efficiency in two-phase gas–liquid agitated vessel is one of the important challenges in the industrial *** fluid dynamics technique(CFD)was used to investigate the effect of four different pitched blade impellers,including 15°,30°,45°and 60°,on the mixing quality of gas–liquid agitated *** multiphase flow behavior was modeled by Eulerian–Eulerian multiphase approach,and RNG k-εwas used to model the *** CFD results showed that a strong global vortex plays the main role on the mixing quality of the gas phase in the *** on the standard deviation criterion,it was observed that the axial distribution of the gas phase in the 30°impeller is about 55%better than the *** addition,the results showed that the 30°impeller has a uniform radial distribution over the other impellers and the maximum gas phase holdup in the *** of the power consumption of the impellers showed that the 30°impeller has the highest power consumption among the other pitched blade ***,examine the effect of same power condition for pitched blade impellers showed that the 30°impeller has the best mixing quality in this condition.

关键词： Pitched blade impeller Mixing CFD Multiphase flow RNG k-εmodel