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International Journal of Intelligent Computing and Cybernetics 2018年第2期11卷 181-196页

作者： hamed tirandaz Ali Karami-Mollaee Department of Electrical and Computer Engineering Hakim Sabzevari UniversitySabzevarIran

Purpose-The purpose of this paper is to propose a novel and secure image transmission based on the unpredictable behavior of the chaotic ***/methodology/approach-The proposed approach includes two main contributions:synchronization scheme and transmission *** synchronization scheme benefits the advantage of the fractional-order active synchronization method.A new control law is derived to asymptotically synchronize the underlined fractional-order Bloch chaotic *** validity of the proposed synchronization scheme is proved by the Lyapunov stability ***,a novel image transmission scheme is designed to transfer image data via chaotic signals,which modulates the encrypted data in the sender signals and demodulates it at the receiver ***-Numerical simulations are provided to show the validity and effectiveness of the proposed image transmission ***,the performance of the image transmission system is evaluated using some illustrative examples and their corresponding statistical *** results demonstrate the effectiveness of the proposed method in comparison with other proposed methods in this ***/value–A new chaos-based image transmission system is developed based on the synchronization of Bloch chaotic *** introduced transmission system is interesting and could be applicable to any kind of secure image/video transmission.

关键词： Active control Bloch chaotic system Fractional calculus Image transmission system Secure communication

Actuator and sensor fault isolation in a class of nonlinear dynamical systems

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Journal of Automation and Intelligence 2024年第2期3卷 57-72页

作者： hamed tirandaz Christodoulos Keliris Marios M.Polycarpou KIOS Research Center for Intelligent Systems and Networks and the Department of Electrical and Computer EngineeringUniversity of CyprusNicosia 1678Cyprus

Fault isolation in dynamical systems is a challenging task due to modeling uncertainty and measurement noise,interactive effects of multiple faults and fault *** paper proposes a unified approach for isolation of multiple actuator or sensor faults in a class of nonlinear uncertain dynamical *** and sensor fault isolation are accomplished in two independent modules,that monitor the system and are able to isolate the potential faulty actuator(s)or sensor(s).For the sensor fault isolation(SFI)case,a module is designed which monitors the system and utilizes an adaptive isolation threshold on the output residuals computed via a nonlinear estimation scheme that allows the isolation of single/multiple faulty sensor(s).For the actuator fault isolation(AFI)case,a second module is designed,which utilizes a learning-based scheme for adaptive approximation of faulty actuator(s)and,based on a reasoning decision logic and suitably designed AFI thresholds,the faulty actuator(s)set can be *** effectiveness of the proposed fault isolation approach developed in this paper is demonstrated through a simulation example.

关键词： Actuator and sensor fault isolation Adaptive approximation Observer-based fault diagnosis Reasoning-based decision logic

Surface metal-matrix composites based on AZ91 magnesium alloy via friction stir processing:A review

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1278-1296页

作者： hamed Mirzadeh School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehranIran

This monograph presents an overview of friction stir processing(FSP)of surface metal-matrix composites(MMCs)using the AZ91 magnesium *** reported results in relation to various reinforcing particles,including silicon carbide(SiC),alumina(Al_(2)O_(3)),quartz(SiO_(2)),boron carbide(B_(4)C),titanium carbide(TiC),carbon fiber,hydroxyapatite(HA),in-situ formed phases,and hybrid reinforcements are ***91 composite fabricating methods based on FSP are explained,including groove filling(grooving),drilled hole filling,sandwich method,stir casting followed by FSP,and formation of in-situ *** effects of introducing second-phase particles and FSP process parameters(e.g.,tool rotation rate,traverse speed,and the number of passes)on the microstructural modification,grain refinement,homogeneity in the distribution of particles,inhibition of grain growth,mechanical properties,strength–ductility trade-off,wear/tribological behavior,and corrosion resistance are ***,useful suggestions for future work are proposed,including focusing on the superplasticity and superplastic forming,metal additive manufacturing processes based on friction stir engineering(such as additive friction stir deposition),direct FSP,stationary shoulder FSP,correlation of the dynamic recrystallization(DRX)grain size with the Zener–Hollomon parameter similar to hot deformation studies,process parameters(such as the particle volume fraction and external cooling),and common reinforcing phases such as zirconia(ZrO_(2))and carbon nanotubes(CNTs).

关键词： surface composites magnesium alloys friction stir processing severe plastic deformation thermomechanical processing

Minimum Reservoir Water Level in Hydropower Dams

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 1017-1024页

作者： hamed Sarkardeh Department of Civil Engineering Hakim Sabzevari UniversitySabzevarIran

Vortex formation over the intakes is an unde- sirable phenomenon within the water withdrawal process from a dam reservoir. Calculating the minimum operating water level in power intakes by empirical equations is not a safe way and sometimes contains some errors. Therefore, current method to calculate the critical submergence of a power intake is construction of a scaled physical model in parallel with numerical model. In this research some pro- posed empirical relations for prediction of submergence depth in power intakes were validated with experimental data of different physical and numerical models of power intakes. Results showed that, equations which involved the geometry of intake have better correspondence with the experimental and numerical data.

关键词： Power intake. Vortex Critical submergence Physical and numerical models Empirical equations

Microstructural evolution and mechanical properties of friction stir-welded C71000 copper–nickel alloy and 304 austenitic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2018年第11期25卷 1294-1303页

作者： hamed Jamshidi Aval Department of Materials and Industrial Engineering Babol Noshirvani University of Technology

Dissimilar joints comprised of copper–nickel and steel alloys are a challenge for manufacturers in modern industries, as these metals are not thermomechanically or chemically well matched. The present study investigated the effects of tool rotational speed and linear speed on the microstructure and mechanical properties of friction stir-welded C71000 copper–nickel and 340 stainless steel alloys using a tungsten carbide tool with a cylindrical pin. The results indicated that a rotational-to-linear speed ratio of 12.5 r/mm did not cause any macro defects, whereas some tunneling defects and longitudinal cracks were found at other ratios that were lower and higher. Furthermore, chromium carbide was formed on the grain boundaries of the 304 stainless steel near the shoulder zone and inside the joint zone, directing carbon and chromium penetration toward the grain boundaries. Tensile strength and elongation percentages were 84% and 65% of the corresponding values in the copper–nickel base metal, respectively.

关键词： dissimilar friction stir welding copper–nickel alloy austenitic stainless steel microstructure mechanical properties

Optimal State Estimation and Fault Diagnosis for a Class of Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 517-526页

作者： hamed Kazemi Alireza Yazdizadeh Department of Electrical Engineering Shahid Beheshti UniversityTehran ***Iran

This study proposes a scheme for state estimation and,consequently,fault diagnosis in nonlinear ***,an optimal nonlinear observer is designed for nonlinear systems subject to an actuator or plant *** utilizing Lyapunov's direct method,the observer is proved to be optimal with respect to a performance function,including the magnitude of the observer gain and the convergence *** observer gain is obtained by using approximation of Hamilton-Jacobi-Bellman(HJB)*** approximation is determined via an online trained neural network(NN).Next a class of affine nonlinear systems is considered which is subject to unknown disturbances in addition to fault *** this case,for each fault the original system is transformed to a new form in which the proposed optimal observer can be applied for state estimation and fault detection and isolation(FDI).Simulation results of a singlelink flexible joint robot(SLFJR)electric drive system show the effectiveness of the proposed methodology.

关键词： Differential geometry fault detection and isolation(FDI) fault diagnosis neural network(NN) nonlinear observer and filter design optimal state estimation

Charge structure factors of doped armchair nanotubes in the presence of electron-phonon interaction

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Chinese Physics B 2020年第9期29卷 415-422页

作者： hamed Rezania Farshad Azizi Department of Physics Razi UniversityKermanshahIran

We present the behaviors of both dynamical and static charge susceptibilities of doped armchair nanotubes using the Green function approach in the context of Holstein-model ***,the effects of magnetization and gap parameter on the the plasmon modes of armchair nanotube are investigated via calculating correlation function of charge density *** phase approximation has been implemented to find the interacting dynamical charge *** electrons in this systems interacts with each other by mediation of dispersionless Holstein *** results show that the increase of gap parameter leads to decreasing intensity of charge collective *** the frequency position of the collective mode tends to higher frequencies due to the gap *** the number of collective excitation mode decreases with chemical potential in the presence of electron-phonon *** the temperature dependence of static charge structure factor of armchair nanotubes is *** effects of the gap parameter,magnetization and electron-phonon interaction on the static structure factor are addressed in details.

关键词： armchair nanotube Green's function

Drill bit wear monitoring and failure prediction for mining automation

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International Journal of Mining Science and Technology 2023年第3期33卷 289-296页

作者： hamed Rafezi Ferri Hassani Department of Mining and Materials Engineering McGill UniversityMontreal H3A 0G4Canada

This article introduces a novel approach for tricone bit wear condition monitoring and failure prediction for surface mining applications.A successful bit health monitoring system is essential to achieve fully autonomous blasthole *** this research in-situ vibration signals were analyzed in timefrequency domain and signals trend during tricone bit life span were investigated and introduced to support the development of artificial intelligence(AI)*** addition to the signal statistical features,wavelet packet energy distribution proved to be a powerful indicator for bit wear *** artificial neural network(ANN)models were designed,trained and evaluated for bit state ***,an ANN architecture and feature vector were introduced to classify the bit condition and predict the bit failure.

关键词： Drilling vibration Condition monitoring Failure prediction Bit wear Wavelet energy Mining automation

Drilling signals analysis for tricone bit condition monitoring

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International Journal of Mining Science and Technology 2021年第2期31卷 187-195页

作者： hamed Rafezi Ferri Hassani Department of Mining and Materials Engineering McGill UniversityMontreal H3A 0G4Canada

This paper presents a novel approach to investigate the relations between drilling signals and bit wear condition in real world full-scale mining *** research addresses the increasing demand for automation in mining to increase the efficiency,safety,and ability to work in harsh environments.A crucial issue in fully autonomous unmanned drilling is to have a system to detect the bit wear condition through the drilling signals analysis in real *** this work,based on extensive field studies,a novel qualitative method for tricone bit wear state classification is developed and *** relations between drilling vibration as well as electric motor current signals and bit wear are investigated and bit failure vibration frequencies,regardless of the geological conditions,are *** failure frequencies are experimentally investigated and analytically ***,the effect of bit design parameters on the failure frequencies is presented for the application of bit wear condition monitoring and bit failure prediction.

关键词： Drilling Tricone bit Vibration Wear Condition monitoring Failure prediction

Wearable Healthcare and Continuous Vital Sign Monitoring with IoT Integration

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Computers, Materials & Continua 2024年第10期81卷 79-104页

作者： hamed Taherdoost Department of Arts Communications and Social SciencesUniversity Canada WestVancouverBC V6Z 0E5Canada GUS Institute Global University SystemsLondonEC1N 2LXUK Hamta Group Hamta Business CorporationVancouverBC V6E 1C9Canada Q Minded Quark Minded Technology Inc.VancouverBC V6E 1C9Canada

Technical and accessibility issues in hospitals often prevent patients from receiving optimal mental and physical health care,which is essential for independent living,especially as societies age and chronic diseases like diabetes and cardiovascular disease become more *** advances in the Internet of Things(IoT)-enabled wearable devices offer potential solutions for remote health monitoring and everyday activity recognition,gaining significant attention in personalized *** paper comprehensively reviews wearable healthcare technology integrated with the IoT for continuous vital sign *** papers were extracted and analyzed using a systematic numerical review method,covering various aspects such as sports monitoring,disease detection,patient monitoring,and medical *** review highlights the transformative impact of IoTenabled wearable devices in healthcare,facilitating real-time monitoring of vital signs,including blood pressure,temperature,oxygen levels,and heart *** from the reviewed papers demonstrate high accuracy and efficiency in predicting health conditions,improving sports performance,enhancing patient care,and diagnosing *** integration of IoT in wearable healthcare devices enables remote patient monitoring,personalized care,and efficient data transmission,ultimately transcending traditional boundaries of healthcare and leading to better patient outcomes.

关键词： Wearable healthcare IoT integration patient care remote patient monitoring real-time data transmission health technology