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A Novel Method for Maximum Power Point Tracking of the Grid-Connected Three-Phase Solar Systems Based on the PV Current Prediction

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Chinese Journal of Electronics 2023年第2期32卷 353-364页

作者： saeid Bairami Mahdi Salimi Davar Mirabbasi Department of Electrical Engineering Ardabil Branch Islamic Azad University Faculty of Engineering and Science University of Greenwich

In this paper, it is first attempted to provide a small signal model of the photovoltaic(PV) system, DC-DC boost converter, and pulse width modulation(PWM) generator. Then, a technique is provided for maximum power point tracking(MPPT) in grid-connected solar systems based on variable and adaptive perturbation and observation with predictive control of the PV current. An innovative aspect of the proposed predictive current control method is to use the current controller to achieve the value of PV impedance, which has been used in DC-DC boost converter. The proposed method is to obtain the coming current value on the basis of the current predictive model. The goal of the proposed method is to make the DC-DC boost converter inductor current track the current reference. Voltage and current ripple minimization is added to the cost function simultaneously as a system constraint to optimize system *** reduces the amount of voltage and current fluctuations around the maximum power point. The proposed method is capable of detecting rapid changes in solar radiation. A sudden and simultaneous increase in voltage and current is detected by the algorithm and then the duty cycle becomes increasing instead of decreasing. The simulation is carried out in MATLAB Simulink environment in real-time for a 26.6 k W three-phase grid-connected solar system. The simulation results of current predictive control are compared with perturbation and observation techniques and linear voltage and current proportional integral derivative(PID) controller-based adaptive *** results show that the total harmonic distortion(THD%) of the inverter voltage with proposed method has been reduced by 0.16% compared to the PID *** addition, the THD% of the current in the proposed method is reduced by 0.1% compared to the PID *** solar system output voltage variation of the proposed method is less than 5 V.

关键词： Maximum power point trackers Fluctuations Voltage fluctuations Simulation Prediction algorithms Inverters Real-time systems

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(α,β)-fuzzy Subalgebras of Q-algebras

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模糊系统与数学 2008年第1期22卷 54-61页

作者： Arsham Borumand saeid Dept of Math. Shahid Bahonar University of Kerman Kerman Iran

In this note by two relations belonging to (∈) and quasi-coincidence (q) between fuzzy points and fuzzy sets, the notion of (α,β)-fuzzy Q-algebras, the level Q-subalgebra is introduced where α,β are any two of {∈,q,∈∨q,∈∧q} with α≠∈∧q. Then we state and prove some theorems which determine the relationship between these notions and Q-subalgebras. The images and inverse images of (α,β)-fuzzy Q-subalgebras are defined, and how the homomorphic images and inverse images of (α,β)-fuzzy Q-subalgebra becomes (α,β)-fuzzy Q-algebras are studied.

关键词： Q代数模糊子代数准一致性属于

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Rapidly Estimating Natural Gas Compressibility Factor

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Journal of Natural Gas Chemistry 2007年第4期16卷 349-353页

作者： Alireza Bahadori saeid Mokhatab Brian F.Towler Department of Chemical Engineering Curtin University of Technology GPO Box 1987PerthWA 6845Australia Process Technology Department Tehran Raymand Consulting Engineers TehranIran Chemical and Petroleum Engineering Department University of Wyoming Laramie.WYUSA

Natural gases containing sour components exhibit different gas compressibility factor （Z） behavior than do sweet gases. Therefore, a new accurate method should be developed to account for these differences. Several methods are available today for calculating the Z-factor from an equation of state. However, these equations are more complex than the foregoing correlations, involving a large number of parameters, which require more complicated and longer computations. The aim of this study is to develop a simplified calculation method for a rapid estimating Z-factor for sour natural gases containing as much as 90% total acid gas. In this article, two new correlations are first presented for calculating the pseudo- critical pressure and temperature of the gas mixture as a function of the gas specific gravity. Then, a simple correlation on the basis of the standard gas compressibility factor chart is introduced for a quick estimation of sweet gases＇ compressibility factor as a function of reduced pressure and temperature. Finally, a new corrective term related to the mole fractions of carbon dioxide and hydrogen sulfide is developed.

关键词： natural gas compressibility factor sour gas critical pressure critical temperature

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Numerical modeling of local scour of non-uniform graded sediment for two arrangements of pile groups

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International Journal of Sediment Research 2023年第4期38卷 597-614页

作者： saeid Okhravi Saeed Gohari Mahdi Alemi Rodrigo Maia Institute of Hydrology Slovak Academy of Sciences Department of Water Engineering College of Agriculture Bu-Ali Sina University Departamento de Engenharia Civil Faculdadede Engenharia Universidade do Porto CIIMAR-Interdisciplinary Centre of Marine and Environmental Research University of Porto

A three-dimensional(3D) non-hydrostatic numerical model is established to investigate local scour around four aligned circular piles in uniform and non-uniform sediment mixtures and to provide information for improving scour countermeasures design. In the current study, unsteady Reynolds averaged Navier-Stokes(URANS) equations along with a Re-normalization Group(RNG) k-ε model were applied to simulate the flow field. A non-uniform sediment transport model was applied to estimate the bedload transport. The simulations lasted up to 8 h. The laboratory results of a reference single pile case in uniform and non-uniform sediment were utilized to validate the simulation results of bed elevation changes and time evolution of scour depth and reflected a good agreement. The influence of pile spacing for two arrangements of pile groups, one column(tandem) and two columns(nontandem) of four aligned piles, on spatial/temporal variations of the bed surface in both sediment bed configurations are discussed in detail. The results reveal the significant effects of the pile spacing on the flow field and patterns of scour hole formation and sediment deposition. In general, lower pile spacing results in more scour upstream of the front pile(s) and shifts deposition more downstream due to the existence of higher energy in the wake region of the piles for both sediment types. Side scouring dominates for non-uniform sediment around each pile due to flow deviating because of the presence of relatively larger particles in front of the pile(s). For non-uniform sediment, deposition begins to develop at the exit area of the scour hole and enhances boundary resistance to scour. The knowledge gained from this study is suitable for the accurate determination of riprap dimensions around the front pile(s)and rear piles in a pile group.

关键词： Local bridge pier scour Non-uniform sediment Numerical modeling Pile groups Pile spacing Sediment transport

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An Efficient Hybrid Model Based on Modified Whale Optimization Algorithm and Multilayer Perceptron Neural Network for Medical Classification Problems

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Journal of Bionic Engineering 2022年第5期19卷 1504-1521页

作者： saeid Raziani Sajad Ahmadian Seyed Mohammad Jafar Jalali Abdolah Chalechale Department of Computer Engineering Razi UniversityKermanshah ***Iran Faculty of Information Technology Kermanshah University of TechnologyKermanshah ***Iran Institute for Intelligent Systems Research and Innovation(IISRI) Deakin UniversityWaurn PondsMelbourne 3217Australia

Feedforward Neural Network(FNN)is one of the most popular neural network models that is utilized to solve a wide range of nonlinear and complex *** models such as stochastic gradient descent have been developed to train ***,they mainly suffer from falling into local optima leading to reduce the accuracy of ***,the convergence speed of training process depends on the initial values of weights and biases in ***,these values are randomly determined by most of the training *** deal with these issues,in this paper,we develop a novel evolutionary algorithm by modifying the original version of Whale Optimization Algorithm(WOA).To this end,a nonlinear function is introduced to improve the exploration and exploitation phases in the search process of ***,the modified WOA is applied to automatically obtain the initial values of weights and biases in FNN leading to reduce the probability of falling into local *** addition,the FNN model trained by the modified WOA is used to develop a classification approach for medical diagnosis *** medical diagnosis datasets are utilized to evaluate the efficiency of the proposed ***,four evaluation metrics including accuracy,AUC,specificity,and sensitivity are used in the experiments to compare the performance of classification *** experimental results demonstrate that the proposed method is better than other competing classification models due to achieving higher values of accuracy,AUC,specificity,and sensitivity metrics for the used datasets.

关键词： Feed forward neural network Meta-heuristic algorithm Whale optimization algorithm Optimization Classification Bionic algorithm

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Relation between mineral composition of human hair and common illnesses

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Chinese Science Bulletin 2012年第26期57卷 3460-3465页

作者： MICHALAK Izabela CHOJNACKA Katarzyna saeid Agnieszka Institute of Inorganic Technology and Mineral Fertilizers Wroc aw University of Technology25 SmoluchowskiegoWroc aw 50-372Poland

The aim of the present study was to find the relation between mineral composition of human hair and illnesses such as infections of the respiratory system,asthma,vertigo,migraine,nervousness,hair loss,dandruff,brittle fingernails and white spots on *** mineral content of human hair was determined by multielemental analysis using ICP-OES and *** about the health condition of the examined subjects was obtained by *** was found that the hair of individuals who currently suffered from infections of the respiratory system or who had asthma had higher Zr content,the hair of sufferers of vertigo had a lower Ca,La and Sr content and in the hair of migraine sufferers the W content was higher than in the hair of healthy *** level of K in the hair of nervous people was three times higher than in hair of people who never suffered from *** who complained of hair loss had an increased level of Cu in the *** individuals with dandruff,brittle fingernails and white spots on fingernails,the content of Ca and La in the hair was higher than in the hair of individuals who did not suffer from any of these *** results of this study indicate that the metal content in hair could be used in the diagnosis of some common illnesses.

关键词：常见疾病头发矿物组成呼吸系统感染 ICP-OES ICP-MS 健康状况矿物质含量

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3D numerical analysis of drilling process： heat, wear, and built-up edge

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Advances in Manufacturing 2018年第2期6卷 204-214页

作者： Mohammad Lotfi saeid Amini Ihsan Yaseen AI-Awady Department of Manufacturing Faculty of Mechanical Engineering University of Kashan Kashan Iran

In this study, a 3D finite element model is developed to investigate the drilling process of AISI 1045 steel, and particularly, the heat and wear on the drill faces. To model drill wear, a modified Usui flank wear rate is used. Experiments are used for the verification of the simulated model and the evaluation of the surface rough- ness and built-up edge. A comparison of the predicted and experimental thrust forces and flank wear rates revealed that the predicted values had low errors and were in good agreement with the experimental values, which showed the utility of the developed model for further analysis. Accordingly, a heat analysis indicated that approximately half the generated heat in the cutting zone was conducted to the drill bit. Furthermore, material adhesion occurred in localized heat areas to a great extent, thus resulting in wear acceleration. A maximum flank wear rate of 0.026 1 mm/s was observed when the rotary speed and feed rate were at the lowest and highest levels, respectively. In the reverse cutting condition, a minimum flank wear rate of 0.016 8 mm/s was observed.

关键词： Drilling Built-up edge Heat Flank wear Force

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A modified model of a single rock joint's shear behavior in limestone specimens

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International Journal of Mining Science and Technology 2016年第4期26卷 577-580页

作者： Dindarloo saeid R. Siami-Irdemoosa Elnaz Department of Mining and Nuclear Engineering missouri University of Science and Technology Rolla 65409 USA Department of geosciences and Geological and Petroleum Engineering Missouri University of science and Technology Rolla 65409 USA

The shear behavior of a single rock joint in limestone specimens,under a constant normal load(CNL),was analyzed in this *** specimens with different asperity roughness were prepared and ***'s model of a rock joint's shear behavior,under CNL,was modified to render a better representation of the data *** model's applicability was *** proposed model showed better correlation with experimental *** also,requires fewer *** steps to calculate all the necessary variables for the model are discussed.

关键词： Limestone rockjoints Constant normalload Direct shear test Shear behavior

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Reduced-order functional observers with application to partial state estimation of linear systems with input-delays

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Journal of Control and Decision 2015年第4期2卷 233-256页

作者： Reza Mohajerpoor Hamid Abdi saeid Nahavandi Centre for Intelligent Systems Research(CISR) Deakin UniversityWaurn PondsAustralia

Reduced-order multi-functional observer design for multi-input multi-output linear timeinvariant(LTI)systems with constant delayed-inputs is *** research is useful in the input estimation of LTI systems with actuator delay,as well as system monitoring and fault detection of these *** approaches for designing an asymptotically stable functional observer for the system are proposed:delay-dependent and *** delay-dependent observer is infinite-dimensional,while the delay-free structure is ***,since the delay-free observer does not require any information on the time delay,it is more practical in real ***,the delay-dependent observer contains less restrictive assumptions and covers more variety of *** proposed observer design schemes are novel,simple to implement,and have improved numerical features compared to some of the other available approaches to design(unknown-input)functional *** addition,the proposed observers usually possess lower order than ordinary Luenberger observers,and the design schemes do not need the observability or detectability requirements of the *** necessary and sufficient conditions of the existence of an asymptotic observer in each scenario are *** extensions of the proposed observers to systemswith multiple delayed-inputs are also *** numerical examples and simulation results are employed to support our theories.

关键词： functional observer unknown-input observer time delay systems functional observability unknown-input functional observability

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Q-learning based control for energy management of series-parallel hybrid vehicles with balanced fuel consumption and battery life

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能源与人工智能(英文) 2023年第1期11卷 118-128页

作者： saeid Ahmadian Mohammad Tahmasbi Reza Abedi Department of Mechanical Engineering Sharif University of TechnologyTehranIran Department of Electrical and Computer Engineering Concordia UniversityMontrealQCCanada Department of Mechanical Engineering K.N.Toosi University of TechnologyTehranIran

The present study investigates an energy management strategy based on reinforcement learning for seriesparallel hybrid vehicles. Hybrid electric vehicles allow using more advanced power management policies because of their complexity of power management. Towards this feature, a Q-Learning algorithm is proposed to design an energy management strategy. Compared to previous studies, an online reward function is defined to optimize fuel consumption and battery life cycle. Moreover, in the provided method, prior knowledge of the cycle and exact modeling of the vehicle are not required. The introduced strategy is simulated for four driving cycles in MATLAB software linked with ADVISOR. The simulation results show that in the HWFET cycle, the fuel consumption decreases by 1.25 %, and battery life increases by 65% compared to the rule-based method implemented in ADVISOR. Also, the results for the other driving cycles confirm the self-improvement property. In addition, it has been depicted that in the case of change in the driving cycle, the method performance has been maintained and gained better performance than the rule-based controller.

关键词： Hybrid electric vehicles Series-parallel configuration Power management policy Reinforcement learning Q-Learning

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