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Dynamic observer-based controllers for linear uncertain systems

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控制理论与应用（英文版） 2013年第2期11卷 193-199页

作者： Arash GOLABI mohammad taghi Hamidi BEHESHTI mohammad Hasan ASEMANI Department of Electrical and Computer Engineering Tarbiat Modares University

This paper addresses robust controller design for uncertain linear systems via a dynamic observer-based controller. A dynamic observer is an alternative structure for a classical observer which can be regarded as a general form of a usual observer and has additional degrees of freedom in the observer structure. Using this new observer structure, a new observer-based controller for linear systems is proposed. Some strict linear matrix inequalities （LMIs） have been given to find the dynamic observer parameters and controller gain. It is shown that dynamic observer can be used effectively for tackling the drawbacks of the classical observer-based robust controller design methods. As an advantage, LMIs are derived even in the presence of uncertainties in system, input and output matrices simultaneously, whereas by using the traditional observer, bilinear matrix inequalities （BMIs） are given in the presence of such uncertainties. Moreover, the proposed LMIs do not imply the equality constraint. Simulation results are used to illustrate the effectiveness of the proposed design technique.

关键词： Dynamic observer Uncertain systems Linear matrix inequality (LMI) Robust control Output feedbackcontrol

In vitro antiproliferative and apoptosis-inducing activities of crude ethyle alcohole extract of Quercus brantii *** and subsequent fractions

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Chinese Journal of Natural Medicines 2016年第3期14卷 196-202页

作者： mohammad-taghi Moradi Ali Karimi Somayeh Alidadi Student's Research Committee Shahrekord University of Medical Science Medical Plants Research Center Shahrekord University of Medical Science Clinical Biochemistry Research Center Shahrekord University of Medical Science

Cancer cell resistance to widely used chemotherapeutic agents is gradually developed. Natural products, mainly isolated from medicinal plants, have been considered as valuable sources for herbal anticancer drugs. The present study aimed to evaluate in vitro antiproliferative and apoptosis-inducing activities of crude ethyle alcohole extract and four fractions of Q. brantii acorn. Crude ethyle alcohole extract of Q. brantii acorn was prepared and subjected to fractionation with different polarity. Subsequently, the extract and the fractions wereevaluated for their in vitro antiproliferative activity in two cancerous(Hela and AGS) and one normal(HDFs) cell lines using MTT [3-(4, 5-dimethylthiazol-2ol) 2, 5 diphenyltetrazoliumbromide] assay. To determine whether the cytotoxicity of these compounds involved the induction of apoptosis, Hela cells were treated with IC_(50) concentrations of test compounds, stained with both propidium iodide(PI) and Annexin V-fluorescein isothiocyanate(FITC), and analyzed by flow cytometry. In vitro cytotoxicity assay showed that the cell viability was significantly reduced in a dose-dependent manner following treatment with crude ethyle alcohole extract and Cholophorm and n-Butanol fractions. Based on the probit regression model, antiproliferative activities of crude ethyle alcohole extract, Cholophorm fraction, and n-Butanol fraction on Hela and AGS cells and HDFs cells were significantly different(P < 0.001). The results of flow cytometric analysis showed that crude ethyle alcohole extract and two fractions of Q. brantii acorn induced early apoptotic cell death. These findings suggest that crude ethyle alcohole extract and Cholophorm and n-Butanol fractions of Q. brantii acorn suppress the proliferation of cancer cells through induction of early apoptosis.

关键词： Quercus brantii Lindl Cancer Proliferation Apoptosis

Task Allocation Approach for Minimizing Make-Span inWireless Sensor Actor Networks

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Computer Systems Science & Engineering 2021年第11期39卷 165-178页

作者： mohammad Reza Okhovvat mohammad taghi Kheirabadi Ali Nodehi Morteza Okhovvat Department of Computer Engineering Gorgan BranchIslamic Azad UniversityGorganIran Health Management and Social Development Research Center Golestan University of Medical SciencesGorganIran

Wireless Sensor Actor Networks(WSANs)have contributed to the development of pervasive computing wherein time consideration to perform the tasks of pervasive applications is ***,time constraint is one of the major challenges of *** this paper,we propose an analytical approach based on queuing theory to minimize the total time taken for completion of tasks,i.e.,make-span,in WSANs with hybrid *** best allocation rates of tasks to actor nodes are figured out through solving inequities and qualities resulting from a steady state analysis of the proposed *** the calculated tasks arrival rates at each of the actors,the make-span could be *** assess the accuracy of the tasks assignment rates to each of the actors attained from the suggested analytical approach and to provide a graphical representation of the WSAN a formal model in terms of the generalized stochastic Petri net(GSPN)is *** proposed GSPN model is analyzed,tasks distribution weights to the actors are determined,and then tasks allocation rates can be *** the results achieved from the analytical approach and the GSPN model demonstrates that allocation rates and hence,the make-span figured out from proposed approach and the formal model are the *** results in typical scenarios show shorter make-span and longer network lifetime compared to when one of the two popular traditional task allocation algorithms,namely,opportunistic load balancing(OLB),and stochastic allocation(SA)algorithms,is used.

关键词： GSPN make-span optimization queuing system task allocation

One-pot synthesis of acenaphtho[l,2-b]furan derivatives

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Chinese Chemical Letters 2012年第2期23卷 169-172页

作者： mohammad taghi Goldani Reza Sandaroos Saman Damavandi Department of Chemical Engineering Islamic Azad UniversityBirjand BranchBirjandlran Department of Chemistry Faculty of ScienceBirjand UniversityBirjandIran Department of Chemistry Sarvestan BranchIslamic Azad UniversitySarvestanlran

New 9-（alkyl or aryl）acenaphtho[l,2-b]furan-8-（alky or aryl）amine compounds has herein been reported by one-pot reaction of （acenaphthylen-l-yloxy）trimethylsilane,alkyl and aryl aldehydes,and aryl and alky isocy... 详细信息

关键词： One-pot reaction Acenaphtho[l 2-b]furan-8-amine Isocyanides

Soft sensor design for hydrodesulfurization process using support vector regression based on WT and PCA

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Journal of Central South University 2015年第2期22卷 511-521页

作者： Saeid Shokri mohammad taghi Sadeghi Mahdi Ahmadi Marvast Shankar Narasimhan Department of Chemical Engineering Iran University of Science and Technology (IUST) Tehran 16765?163 Iran Process & Equipment Technology Development Division Research Institute of Petroleum Industry (RIPI) Tehran 14665?137 Iran Department of Chemical Engineering IIT Madras Chennai 600036 India

A novel method for developing a reliable data driven soft sensor to improve the prediction accuracy of sulfur content in hydrodesulfurization(HDS) process was proposed. Therefore, an integrated approach using support vector regression(SVR) based on wavelet transform(WT) and principal component analysis(PCA) was used. Experimental data from the HDS setup were employed to validate the proposed model. The results reveal that the integrated WT-PCA with SVR model was able to increase the prediction accuracy of SVR model. Implementation of the proposed model delivers the best satisfactory predicting performance(EAARE=0.058 and R2=0.97) in comparison with SVR. The obtained results indicate that the proposed model is more reliable and more precise than the multiple linear regression(MLR), SVR and PCA-SVR.

关键词： soft sensor support vector regression principal component analysis wavelet transform hydrodesulfurization process

Sustainable functionalization and modification of materials via multicomponent reactions in water

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Frontiers of Chemical Science and Engineering 2022年第9期16卷 1318-1344页

作者： Siamak Javanbakht Tahereh Nasiriani Hassan Farhid mohammad taghi Nazeri Ahmad Shaabani Department of Organic Chemistry Shahid Beheshti UniversityTehran ***Iran Рeoples’Friendship University of Russia(RUDN University) Moscow 117198Russian Federation

In materials chemistry,green chemistry has established firm ground providing essential design criteria to develop advanced tools for efficient functionalization and modification of ***,the combination of multicomponent reactions in water and aqueous media with materials chemistry unlocks a new sustainable way for constructing multi-functionalized structures with unique features,playing significant roles in the plethora of *** reactions have received significant consideration from the community of material chemistry because of their great efficiency,simple operations,intrinsic molecular diversity,and an atom and a pot ***,by rational design of multicomponent reactions in water and aqueous media,the performance of some multicomponent reactions could be enhanced by the contributing“natural”form of water-soluble materials,the exclusive solvating features of water,and simple separating and recovering *** date,there is no exclusive review to report the sustainable functionalization and modification of materials in *** critical review highlights the utility of various kinds of multicomponent reactions in water and aqueous media as green methods for functionalization and modification of siliceous,magnetic,and carbonaceous materials,oligosaccharides,polysaccharides,peptides,proteins,and synthetic *** detailed discussion of synthetic procedures,properties,and related applicability of each functionalized/modified material is fully deliberated in this review.

关键词： materials multicomponent reactions modification functionalization water

Evaluation of total load sediment transport formulas using ANN

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International Journal of Sediment Research 2009年第3期24卷 274-286页

作者： Chih Ted YANG Reza MARSOOLI mohammad taghi AALAMI Water Resources Colorado State University Graduate student of Civil-Hydraulics Engineering University of Tabriz Civil-Hydraulics Engineering University of Tabriz

The calculated results from various sediment transport formulas often differ from each other and from measured data. Some parameters in the sediment transport formulas are more effective than others to estimate total sediment load. In this study, an Artificial Neural Network (ANN) model is trained using four dominant parameters of sediment transport formulas. ANN models are able to reveal hidden laws of natural phenomena such as sediment transport process. The results of ANN and some total bed material load sediment transport formulas have been compared to indicate the importance of variables which can be used in developing sediment transport formulas. To train ANN, average flow velocity, water surface slopes, average flow depth, and median particle diameter are used as dominant parameters to estimate total bed material load. Two hundreds and fifty samples are used to train the ANN model. Twenty-four sets of field data not used in the training nor calibration of ANN are used to compare or verify the accuracy of ANN and some well-known total bed material load formulas. The test results show that the ANN model developed in this study using minimum number of dominant factors is a reliable and uncomplicated method to predict total sediment transport rate or total bed material load transport rate. Results show that the accuracy of formulas in descending order are those by Yang (1973), Laursen (1958), Engelund and Hansen (1972), Ackers and White (1973), and Toffaleti (1969). These results are similar to those made by ASCE (1982) based on laboratory and field data not used in this paper. Study results also show that the formulas based on physical laws of sediment transport, like those formulas that were developed based on power concept, are more accurate than other formulas for estimating total bed material sediment load in rivers.

关键词： Artificial Neural Network (ANN) Total bed material load Sediment transport formulas

Fabrication of (Ti,Hf)-rich NiTiHf Alloy Using Graphitic Mold and Crucible

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Journal of Materials Science & Technology 2014年第3期30卷 280-284页

作者： Mahdi Moshref-Javadi Majid Belbasi Seyed Hossein Seyedein mohammad taghi Salehi School of Metallurgy & Materials Engineering Iran University of Science & Technology (IUST)

In this research, fabrication of a （Ti,Hf）-rich NiTiHf alloy by using vacuum induction melting （VIM） process and a graphitic crucible was investigated. For this purpose, casts with the nominal composition of Ni49Ti38Hf15 were prepared in graphitic crucible and mold. Optical microscopy （OM）, scanning electron microscopy （SEM）, energy dispersive X-ray spectroscopy （EDS）, X-ray diffraction （XRD）, and differential scanning calorimetry （DSC） tests were employed to characterize the samples. Results demonstrated that microstructure of the first cast was composted of a B2 austenite phase as well as a great amount of two differently formed （Ti,Hf）C carbides. Moreover, no austenite ＊-＊ martensite transformation peak was detected in the DSC curve of this sample, indicating a drastic decline in the transformation temperatures. In the succeeding cast, however, owing to the formation of carbide layers on the inner surfaces of the graphitic crucible and mold during the initial casting process, the amounts of carbides decreased remarkably. This cast exhibited transformation temperatures above 100℃, while XRD pattern denoted the presence of B19t monoclinic martensite phase at room temperature. All in all, results confirmed that VIM process using graphitic mold and crucible can be considered as an appropriate method for the fabrication of （Ti,Hf）-rich NiTiHf high temperature shape memory alloys.

关键词： High temperature shape memory alloys NiTi Martensite Casting Transformation temperatures Microstructure

Improvement of the prediction performance of a soft sensor model based on support vector regression for production of ultra-low sulfur diesel

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Petroleum Science 2015年第1期12卷 177-188页

作者： Saeid Shokri mohammad taghi Sadeghi Mahdi Ahmadi Marvast Shankar Narasimhan Department of Chemical Engineering Iran University of Science and Technology (IUST) Process and Equipment Technology Development Division Research Institute of Petroleum Industry (RIPI) Department of Chemical Engineering

A novel data-driven, soft sensor based on support vector regression （SVR） integrated with a data compression technique was developed to predict the product quality for the hydrodesulfurization （HDS） process. A wide range of experimental data was taken from a HDS setup to train and test the SVR model. Hyper-parameter tuning is one of the main challenges to improve predictive accuracy of the SVR model. Therefore, a hybrid approach using a combination of genetic algorithm （GA） and sequential quadratic programming （SQP） methods （GA-SQP） was developed. Performance of different optimization algorithms including GA-SQP, GA, pattern search （PS）, and grid search （GS） indicated that the best average absolute relative error （AARE）, squared correlation coefficient （R2）, and computation time （CT）（AARE = 0.0745, R2 = 0.997 and CT = 56 s） was accomplished by the hybrid algorithm. Moreover, to reduce the CT and improve the accuracy of the SVR model, the vector quantization （VQ） technique was used. The results also showed that the VQ technique can decrease the training time and improve prediction performance of the SVR model. The proposed method can provide a robust, soft sensor in a wide range of sulfur contents with good accuracy.

关键词： Soft sensor Support vector regression Hybrid optimization method Vector quantization Petroleum refinery Hydrodesulfurization process Gas oil