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Optimal Design of Fuzzy-AGC Based on PSO&RCGA to Improve Dynamic Stability of Interconnected Multi-area Power Systems

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International Journal of Automation and computing 2020年第4期17卷 599-609页

作者： ali Darvish Falehi Department of Electrical Engineering Shahid Beheshti UniversityTehran ***Iran

Quickly getting back the synchronism of a disturbed interconnected multi-area power system due to variations in loading condition is recognized as prominent issue related to automatic generation control(AGC).In this regard,AGC system based on fuzzy logic,i.e.,so-called FLAGC can introduce an effectual performance to suppress the dynamic oscillations of tie-line power exchanges and frequency in multi-area interconnected power *** from that,simultaneous coordination scheme based on particle swarm optimization(PSO)along with real coded genetic algorithm(RCGA)is suggested to coordinate FLAGCs of the all *** clarify the high efficiency of aforementioned strategy,two different interconnected multi-area power systems,i.e.,three-area hydro-thermal power system and five-area thermal power system have been taken into account for relevant *** potency of this strategy has been thoroughly dealt with by considering the step load perturbation(SLP)in both the under study power *** sum up,the simulation results have plainly revealed dynamic performance of FLAGC as compared with conventional AGC(CAGC)in each power system in order to damp out the power system oscillations.

关键词： Power system dynamic stability fuzzy logic automatic generation control(FLAGC) particle swarm optimization(PSO) real coded genetic algorithm(RCGA) simultaneous coordination scheme

Note on Lower Triassic Gondolelloid Conodont Rediversifications with Emphasis on the Spathian Recovery

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Journal of Earth Science 2024年第4期35卷 1236-1242页

作者： ali Murat Kilic Department of Geological Engineering Faculty of EngineeringBalikesir UniversityBalikesir99100Turkey

Conodonts,as a biotic group,next to ammonoids,pollen and spores,crustaceans and vertebrates,provide proxy clues for environment and age assessments of the rocks in which they *** are widely used for Triassic marine ***,there are various discussions about their multielement taxonomy and evolutionary lineages(e.g.,generation,speciation).Although first studies reported that most Triassic conodont species were unimembrate,studies carried out in the following years maintained that all Triassic conodonts were *** statistical reconstructions of a number of Triassic apparatuses were attempted,the discovery of fused clusters and natural assemblages has subsequently demonstrated that Triassic conodonts are indeed multimembrate,and all of the elements exist together in the same *** present paper aims to clarify the evolutionary relationship and array of some Lower Triassic *** dagisi *** described.

关键词： Triassic Spathian conodont Columbitella Siberia environmental geology

Optimization of cement-based grouts using chemical additives

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第4期9卷 623-637页

作者： Mohammad Reza Azadi ali Taghichian ali Taheri Faculty of Science and Technology Federation University Australia Mewbourne School of Petroleum and Geological Engineering University of Oklahoma Department of Earth Science and Engineering Imperial College

Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after *** are many methods of *** grouting is one of the most common types in which the grout material is injected to the pore spaces of the *** grouting operations,the grout quality is important to achieve the best *** are four main characteristics for a grout mixture including bleeding,setting time,strength,and *** this paper,we try to build some efficient grouting mixtures with different water to cement ratios considering these *** ingredients of grout mixtures built in this study are cement,water,bentonite,and some chemical additives such as sodium silicate,sodium carbonate,and triethanolamine(TEA).The grout mixtures are prepared for both of the sealing and strengthening purposes for a structural *** of each abovementioned ingredient is profoundly *** each ingredient may have positive or negative aspect,an optimization of appropriate amount of each ingredient is *** optimization is based on 200 grout mixture samples with different percentages of ***,some of these grout mixtures are chosen for the introduced *** should be mentioned that grouting operations depend on various factors such as pressure of injection,ground structure and grain size of ***,quality of a grout can be helpful to make an injection easier and *** example,during the injection,a wrong estimated setting time can destroy the injected grout by washing the grout or setting early which prevents *** paper tries to show some tests in easy way to achieve a desirable sample of grout.

关键词： Permeation grouting Bleeding Setting time Chemical additives Cement-based grout

Cavity Control of Prefoldin Nano Actuator (PNA) by Temperature and pH

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Nano-Micro Letters 2012年第2期4卷 110-117页

作者： ali Shokuhfar ali Ghaffari Reza Hasanzadeh Ghasemi Department of Mechanical Engineering K.N. Toosi University of Technology

A molecular dynamics study to investigate the cavity control of Prefoldin based bio nano actuator is presented in this paper. Prefoldin is a molecular chaperone with a jellyfish-like structure containing six long coiled-coil tentacles and a large central cavity. We took the temperature and p H of the medium into account,and analyzed the conformational flexibility of the Prefoldin nano actuator in details. Results show that the prefoldin is a very flexible protein, the conformational state of which appears to depend on the temperature and p H values of the medium. In fact, combining these two control parameters, a suitable environment is provided to capture nano cargoes with specific dimensions. These properties of Prefoldin actuator can be used for drug delivery in the body.

关键词： Prefoldin Nano Actuator(PNA) Cavity control Molecular Dynamics GROMACS

Synthesis and Chemical Shifts Calculation of α-Acyloxycarboxamides Derived from Indane-1,2,3-trione by DFT and HF Methods

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Chinese Journal of Structural Chemistry 2012年第9期31卷 1346-1356页

作者： Hooriye Yahyaei ali Reza Kazemizadeh ali Ramazani Department of Chemistry Zanjan BranchIslamic Azad UniversityP.O.Box 49195-467ZanjanIran

α-Acyloxycarboxamides are synthesized from three-component Passerini reaction between indane-1,2,3-trione, isocyanides, and thiophenecarboxylic acids in quantitative yields. The structures of the final products were confirmed by IR, 1H and 13C NMR spectroscopy, mass spectrometry, and elemental analysis. The B3LYP/HF calculations for computation of 1H and 13C NMR chemical shifts have been carried out for the title compounds at the 6-311＋G＊＊ and 6-311＋＋G＊＊ basis set levels within GIAO and CSGT approaches. Predicted 1H and 13C NMR che-mical shifts have been assigned and compared with experimental 1H and 13C NMR spectra and they are supported each other.

关键词： DFT HF NMR spectra Passerini reaction isocyanide

Stochastic maximum power point tracking of photovoltaic energy system under partial shading conditions

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Protection and Control of Modern Power Systems 2021年第1期6卷 383-395页

作者： Bushra Iqbal ali Nasir ali Faisal Murtaza Department of Electrical Engineering University of Central PunjabLahorePakistan

A large portion of the available power generation of a photovoltaic (PV) array could be wasted due to partial shading, temperature and irradiance effects, which create current/voltage imbalance between the PV modules. Partial shading is a phenomenon which occurs when some modules in a PV array receive non-uniform irradiation due to dust, cloudy weather or shadows of nearby objects such as buildings, trees, mountains, birds etc. Maximum power point tracking (MPPT) techniques are designed in order to deal with this problem. In this research, a Markov Decision Process (MDP) based MPPT technique is proposed. MDP consists of a set of states, a set of actions in each state, state transition probabilities, reward function, and the discount factor. The PV system in terms of the MDP framework is modelled first and once the states, actions, transition probabilities, and reward function, and the discount factor are defined, the resulting MDP is solved for the optimal policy using stochastic dynamic programming. The behavior of the resulting optimal policy is analyzed and characterized, and the results are compared to existing MPPT control methods.

关键词： Maximum power point tracking Markov decision process Photovoltaic energy systems Partial shading

Kinetics and mechanism of titanium hydride powder and aluminum melt reaction

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 165-172页

作者： ali Rasooli Mehdi Divandari Hamid Reza Shahverdi Mohammad ali Boutorabi School of Metallurgy and Materials Engineering Member of Center of Excellence for Advanced Material and Processing (CEAMP) Iran University of Science and Technology Tehran 16844 Iran Department of Materials Faculty of Engineering Tarbiat Modaress University Tehran 14115-143 Iran

Based on the measurement of the released hydrogen gas pressure （PH2）, the reaction kinetics between TiH2 powder and pure aluminum melt was studied at various temperatures. After cooling the samples, the interface of TiH2 powder and aluminum melt was studied. The results show that the-time curves have three regions; in the first and second regions, the rate of reaction conforms zero and one order, respectively; in the third region, the hydrogen gas pressure remains constant and the rate of reaction reaches zero. The main factors that control the rate of reaction in the first and second regions are the penetration of hydrogen atoms in the titanium lattice and the chemical reaction between molten aluminum and titanium, respectively. According to the main factors that control the rate of reaction, three temperature ranges are considered for the reaction mechanism：（a） 700-750°C, （b） 750-800°C, and （c） 800-1000°C. In the first temperature range, the reaction is mostly under the control of chemical reaction; at the temperature range of 750 to 800°C, the reaction is controlled by the diffusion and chemical reaction; at the third temperature range （800-1000°C）, the dominant controlling mechanism is diffusion.

关键词： titanium hydride aluminum reaction kinetics reaction rate constants

Implementation of electrolyte CPA EoS to model solubility of CO2 and CO2+ H2S mixtures in aqueous MDEA solutions

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1912-1920页

作者： alireza Afsharpour ali Haghtalab Department of Chemical Engineering Tarbiat Modares UniversityP.O.Box 14115-114TehranIran Faculty of Chemical and Materials Engineering Shahrood University of TechnologyShahroodIran

The electrolyte version of SRK plus association equation of state(e SRK-CPA Eo S) was employed to correlate CO2 solubility in MDEA aqueous solutions. The applied model comprises the classic form of CPA Eo S including SRK Eo S plus Wertheim association term in addition to MSA theory and Born terms so that the two last terms are responsible for the long-range interactions. A reaction-containing bubble pressure computation technique comprising two nested loops was utilized to model the systems. The internal loop, calculates the liquid phase concentrations via reaction, mass and charge balance equation solving, whereas, the vapor phase concentrations will be obtained in the external one. 470 experimental data were used to correlate binary subsystems and the H2O + MDEA + CO2 ternary system. Since, there not exist any binary VLE data for MDEA + CO2 subsystem, two fitting scenarios were applied. At the first scenario, the binary interaction parameter was assumed equal to zero, while, in second approach the parameter was obtained through ternary system correlation. Both scenarios show very good accuracy in that the Absolute Average Deviation percentages(AAD) obtained were 19.12% and 18.85%, respectively. Also, to show the efficiency of the used model, a comparison between our results and those of the best-known models was ***, having model parameters for H2S solubility from our previous work [A. Afsharpour, Petroleum Science and Technology 35(3)(2017) 292-298], simultaneous solubility of CO2+ H2S mixtures in MDEA solutions was predicted using the e SRK-CPA Eo S with no new optimizable parameters. As the results show,the applied model has a good performance for correlation and prediction of acid gas solubility in a wide range of pressures, temperatures, acid gas loadings, and MDEA concentrations.

关键词： Acid gas solubility MDEA Thermodynamic modeling Phase equilibria CPA EoS Prediction

An interpretable deep learning approach for designing nanoporous silicon nitride membranes with tunable mechanical properties

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npj Computational Materials 2023年第1期9卷 1524-1533页

作者： ali KShargh Niaz Abdolrahim Department of Mechanical Engineering University of RochesterRochesterNY 14627USA Materials Science program University of RochesterRochesterNY 14627USA Laboratory for Laser Energetics University of RochesterRochesterNY 14627USA

The high permeability and strong selectivity of nanoporous silicon nitride(NPN)membranes make them attractive in a broad range of *** their growing use,the strength of NPN membranes needs to be improved for further extending their biomedical *** this work,we implement a deep learning framework to design NPN membranes with improved or prescribed strength *** examine the predictions of our framework using physics-based *** results confirm that the proposed framework is not only able to predict the strength of NPN membranes with a wide range of microstructures,but also can design NPN membranes with prescribed or improved *** simulations further demonstrate that the microstructural heterogeneity that our framework suggests for the optimized design,lowers the stress concentration around the pores and leads to the strength improvement of NPN membranes as compared to conventional membranes with homogenous microstructures.

关键词： tunable prescribed strength