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Coefficient of consolidation by end of arc method

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Journal of Central South University 2015年第1期22卷 332-337页

作者： Mohsen Abbaspout Reza Porhoseini Kazem Barkhordari Ahmad ghorbani School of Technical & Engineering Department of Civil Engineering Yazd UniversityUniversity Blvd School of Mining and Metallurgy Department of Mine Exploration Yazd UniversityUniversity Blvd

One of the most important issues in geotechnical engineering is excess pore pressure caused by clay soil loading and consolidation. Regarding uncertainties and complexities, this issue has long been the subject of attention of many researchers. In this work, a one-dimensional consolidation apparatus was equipped in a way that pore water pressure and settlement could be continuously read and recorded during consolidation process under static loading. The end of primary consolidation was obtained using water pressure changes helping to present a new method for determining the end of primary consolidation and consolidation coefficient. This method was then compared with two classical theory methods of lg t and t. Using Terzaghi's theory, the way of pore pressure dissipation for lg t, t and the new method was found and compared with experimental results. It is concluded that the new method has better results.

关键词： one-dimensional consolidation of soil excess pore pressure end primary consolidation consolidation coefficient static loading

Hybrid classifier for fault location in active distribution networks

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Protection and Control of Modern Power Systems 2020年第1期5卷 194-202页

作者： sadegh Jamali Alireza Bahmanyar Siavash Ranjbar Centre of Excellence for Power System Automation and Operation School of Electrical EngineeringIran University of Science and TechnologyP.O.Box:16846-13114TehranIran

This paper presents a fast hybrid fault location method for active distribution networks with distributed generation(DG)and *** method uses the voltage and current data from the measurement points at the main substation,and the connection points of DG and *** data is used in a single feedforward artificial neural network(ANN)to estimate the distances to fault from all the measuring points.A k-nearest neighbors(KNN)classifier then interprets the ANN outputs and estimates a single fault *** results validate the accuracy of the fault location method under different fault conditions including fault types,fault points,and fault *** performance is also validated for non-synchronized measurements and measurement errors.

关键词： Artificial neural networks Distributed generation Distribution networks Fault location K-nearest neighbors

Bone Injury and Fracture Healing Biology

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维普期刊数据库

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Biomedical and Environmental Sciences 2015年第1期28卷 57-71页

作者： Ahmad Oryan Somayeh Monazzah Amin Bigham-sadegh Comparative Pathology Department of Pathology School of Veterinary Medicine Shiraz University Shiraz 71345 Iran Department of Pathology School of Veterinary Medicine Shiraz University Shiraz 71345 Iran Veterinary Surgery Department of Veterinary Surgery and Radiology Faculty of Veterinary Medicine Shahrekord University Shahrekord *** Iran

Bones are organs of the skeletal system, providing shape, mechanical support, and protection to the body and facilitating the movement. In addition, bones contribute to the mineral homeostasis of the body and have recently been found to participate in endocrine regulation of energy metabolism. The well-known limitations associated with clinical use of autografts and allografts continue to drive efforts to develop bone graft substitutes, using the principles of biomaterials and tissue engineering. Under some stressful and continuous compressive conditions, the ability of the bone tissue to tolerate strength decreases. Whenever these forces overcome the toleration of the bone tissue, bone fracture occurs. years

关键词： bone Bone Injury and Fracture Healing Biology

Mechanical proper ties of lateral transition metal dichalcogenide heterostructures

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Frontiers of physics 2021年第1期16卷 23-29页

作者： sadegh Imani Yengejeh William Wen Yun Wang Centre for Clean Environment and Energy School of Environment and ScienceGriffith UniversityGold Coast CampusSouthport 4222Australia

Transition metal dichalcogenide(TMD)monolayers attract great attention due to their specific structural,electronic and mechanical *** formation of their lateral heterostructures allows a new degree of flexibility in engineering electronic and optoelectronic ***,the mechanical properties of the lateral heterostructures are rarely *** this study,a comparative investigation on the mechanical characteristics of 1H,IT'and 1H/1T'heterostructure phases of different TMD monolayers including molybdenum disulfide(M0S_(2))molybdenum diselenide(MoSe_(2)),Tungsten disulfide(WS_(2)),and Tungsten diselenide(WSe_(2))was conducted by means of density functional theory(DFT)*** results indicate that the impact of the lateral heterostructures has a relatively weak mechanical strength for all the TMD *** significant correlation bet ween the mechanical properties of the TMD monolayers and their structural phases can be used to tune their stiffness of the *** findings,therefore,suggest a novel strategy to manipulate the mechanical characteristics of TMDs by engineering their structural phases for their practical applications.

关键词： transition metal dichalcogenide lateral heterostructures mechanical properties in-plane stiffness tensor density functional theory

Robust Stability Analysis of Smith Predictor Based Interval Fractional-Order Control Systems:A Case Study in Level Control Process

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 762-780页

作者： Majid ghorbani Mahsan Tavakoli-Kakhki Aleksei Tepljakov Eduard Petlenkov Department of Computer Systems Tallinn University of TechnologyTallinn 12618Estonia Faculty of Electrical Engineering K.N.Toosi University of TechnologyTehran ***Iran IEEE

The robust stability study of the classic Smith predictor-based control system for uncertain fractional-order plants with interval time delays and interval coefficients is the emphasis of this *** uncertainties are a type of parametric uncertainties that cannot be avoided when modeling real-world ***,in the considered Smith predictor control structure it is supposed that the controller is a fractional-order proportional integral derivative(FOPID)*** the best of the authors'knowledge,no method has been developed until now to analyze the robust stability of a Smith predictor based fractional-order control system in the presence of the simultaneous uncertainties in gain,time-constants,and time *** three primary contributions of this study are as follows:ⅰ)a set of necessary and sufficient conditions is constructed using a graphical method to examine the robust stability of a Smith predictor-based fractionalorder control system—the proposed method explicitly determines whether or not the FOPID controller can robustly stabilize the Smith predictor-based fractional-order control system;ⅱ)an auxiliary function as a robust stability testing function is presented to reduce the computational complexity of the robust stability analysis;andⅲ)two auxiliary functions are proposed to achieve the control requirements on the disturbance rejection and the noise ***,four numerical examples and an experimental verification are presented in this study to demonstrate the efficacy and significance of the suggested technique.

关键词： Interval uncertainty FOPID controller fractional-order systems robust stability analysis smith predictor

Image Tamper Detection and Multi-Scale Self-Recovery Using Reference Embedding with Multi-Rate Data Protection

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China Communications 2019年第11期16卷 154-166页

作者： Navid Daneshmandpour Habibollah Danyali Mohammad sadegh Helfroush Department of Electrical and Electronics Engineering Shiraz University of Technology

This paper proposes a multi-scale self-recovery(MSSR)approach to protect images against content *** main idea is to provide more resistance against image tampering while enabling the recovery process in a multi-scale quality *** the proposed approach,the reference data composed of several parts and each part is protected by a channel coding rate according to its *** first part,which is used to reconstruct a rough approximation of the original image,is highly protected in order to resist against higher tampering *** parts are protected with lower rates according to their importance leading to lower tolerable tampering rate(TTR),but the higher quality of the recovered *** proposed MSSR approach is an efficient solution for the main disadvantage of the current methods,which either recover a tampered image in low tampering rates or fails when tampering rate is above the TTR *** simulation results on 10000 test images represent the efficiency of the multi-scale self-recovery feature of the proposed approach in comparison with the existing methods.

关键词： tamper detection image recovery multi-scale self-recovery tolerable tampering rate

Estimation of hydraulic jump on corrugated bed using artificial neural networks and genetic programming

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Water Science and Engineering 2013年第2期6卷 189-198页

作者： Akram ABBASPOUR Davood FARSADIZADEH Mohammad Ali ghorbani Department of Water Engineering University of Tabriz

Artificial neural networks （ANNs） and genetic programming （GP） have recently been used for the estimation of hydraulic data. In this study, they were used as alternative tools to estimate the characteristics of hydraulic jumps, such as the free surface location and energy dissipation. The dimensionless hydraulic parameters, including jump depth, jump length, and energy dissipation, were determined as functions of the Froude number and the height and length of corrugations. The estimations of the ANN and GP models were found to be in good agreement with the measured data. The results of the ANN model were compared with those of the GP model, showing that the proposed ANN models are much more accurate than the GP models.

关键词： artificial neural networks genetic programming," corrugated bed, Froude number, hydraulic jump

Image compression based on spatial redundancy removal and image inpainting

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第2期11卷 92-100页

作者： Vahid BASTANI Mohammad sadegh HELFROUSH Keyvan KASIRI Department of Electrical and Electronic Engineering Shiraz University of Technology

We present an algorithm for image compression based on an image inpainting method. First the image regions that can be accurately recovered are located. Then, to reduce the data, information of such regions is removed. The remaining data besides essential details for recovering tile removed regions are encoded to produce output data. At the decoder, an inpainting method is applied to retrieve removed regions using information extracted at the encoder. The image inpainting technique utilizes partial differential equations （PDEs） for recovering information. It is designed to achieve high performance in terms of image compres- sion criteria. This algorithm was examined for various images. A high compression ratio of 1：40 was achieved at an acceptable quality. Experimental results showed attainable visible quality improvement at a high compression ratio compared with JPEG.

关键词： Edge extraction Image compression Image inpainting Spatial redundancy

Effectiveness of two conventional methods for seismic retrofit of steel and RC moment resisting frames based on damage control criteria

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 537-555页

作者： Seyed Bahram Beheshti Aval Hamed sadegh Kouhestani Lida Mottaghi Faculty of Civil Engineering K. N. Toosi University of Technology Tehran 1ran Faculty of Technical and Engineering Science & Culture University Tehran 1ran

This study investigates the efficiency of two types of rehabilitation methods based on economic justification that can lead to logical decision making between the retrofitting schemes. Among various rehabilitation methods, concentric chevron bracing（CCB） and cylindrical friction damper（CFD） were selected. The performance assessment procedure of the frames is divided into two distinct phases. First, the limit state probabilities of the structures before and after rehabilitation are investigated. In the second phase, the seismic risk of structures in terms of life safety and financial losses（decision variables） using the recently published FEMA P58 methodology is evaluated. The results show that the proposed retrofitting methods improve the serviceability and life safety performance levels of steel and RC structures at different rates when subjected to earthquake loads. Moreover, these procedures reveal that financial losses are greatly decreased, and were more tangible by the application of CFD rather than using CCB. Although using both retrofitting methods reduced damage state probabilities, incorporation of a site-specific seismic hazard curve to evaluate mean annual occurrence frequency at the collapse prevention limit state caused unexpected results to be obtained. Contrary to CFD, the collapse probability of the structures retrofitted with CCB increased when compared with the primary structures.

关键词： steel and RC moment resisting frames seismic retrofitting collapse probability concentric chevron bracing(CCB) cylindrical friction damper (CFD)