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CSRWA:Covert and Severe Attacks Resistant Watermarking Algorithm

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Computers, Materials & Continua 2025年第1期82卷 1027-1047页

作者： Balsam Dhyia Majeed amir hossein Taherinia Hadi Sadoghi Yazdi Ahad Harati Faculty of Engineering Ferdowsi University of MashhadMashhad***Iran Department of Computer Techniques Engineering Imam Al-Kadhum CollegeBaghdad10087Iraq

Watermarking is embedding visible or invisible data within media to verify its authenticity or protect *** watermark is embedded in significant spatial or frequency features of the media to make it more resistant to intentional or unintentional *** of these features are important perceptual features according to the human visual system(HVS),which means that the embedded watermark should be imperceptible in these ***,both the designers of watermarking algorithms and potential attackers must consider these perceptual features when carrying out their *** two roles will be considered in this paper when designing a robust watermarking algorithm against the most harmful attacks,like volumetric scaling,histogram equalization,and non-conventional watermarking attacks like the Denoising Convolution Neural Network(DnCNN),which must be considered in watermarking algorithm design due to its rising role in the state-of-the-art *** DnCNN is initialized and trained using watermarked image samples created by our proposed Covert and Severe Attacks Resistant Watermarking Algorithm(CSRWA)to prove its *** this algorithm to satisfy the robustness and imperceptibility tradeoff,implementing the Dither Modulation(DM)algorithm is boosted by utilizing the Just Noticeable Distortion(JND)principle to get an improved performance in this ***,luminance,inter and intra-block contrast are used to adjust the JND values.

关键词： Covert attack digital watermarking DnCNN JND perceptual model robustness

Artificial intelligence in seismology:Advent,performance and future trends

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Geoscience Frontiers 2020年第3期11卷 739-744页

作者： Pengcheng Jiao amir H.alavi Ocean College Zhejiang UniversityZhoushanZhejiang 316021China Department of Civil and Environmental Engineering University of PittsburghPittsburghPA15261USA

Realistically predicting earthquake is critical for seismic risk assessment,prevention and safe design of major *** to the complex nature of seismic events,it is challengeable to efficiently identify the earthquake response and extract indicative features from the continuously detected seismic *** challenges severely impact the performance of traditional seismic prediction models and obstacle the development of seismology in *** their advantages in data analysis,artificial intelligence(AI) techniques have been utilized as powerful statistical tools to tackle these *** typically involves processing massive detected data with severe noise to enhance the seismic performance of *** extracting meaningful sensing data to unveiling seismic events that are below the detection level,AI assists in identifying unknown features to more accurately predicting the earthquake *** this focus paper,we provide an overview of the recent AI studies in seismology and evaluate the performance of the major AI techniques including machine learning and deep learning in seismic data ***,we envision the future direction of the AI methods in earthquake engineering which will involve deep learning-enhanced seismology in an internet-of-things(IoT) platform.

关键词： Seismology Artificial intelligence Machine learning Deep learning Internet-of-Things

New design equations for estimation of ultimate bearing capacity of shallow foundations resting on rock masses

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Geoscience Frontiers 2016年第1期7卷 91-99页

作者： amir H.alavi Ehsan Sadrossadat Department of Civil and Environmental Engineering Michigan State University Department of Civil Engineering Mashhad BranchIslamic Azad University

Rock masses are commonly used as the underlying layer of important structures such as bridges, dams and transportation constructions. The success of a foundation design for such structures mainly depends on the accuracy of estimating the bearing capacity of rock beneath them. Several traditional numerical approaches are proposed for the estimation of the bearing capacity of foundations resting on rock masses to avoid performing elaborate and expensive experimental studies. Despite this fact, there still exists a serious need to develop more robust predictive models. This paper proposes new nonlinear prediction models for the ultimate bearing capacity of shallow foundations resting on non-fractured rock masses using a novel evolutionary computational approach, called linear genetic programming. A comprehensive set of rock socket, centrifuge rock socket, plate load and large-scaled footing load test results is used to develop the models. In order to verify the validity of the models, the sensitivity analysis is conducted and discussed. The results indicate that the proposed models accurately characterize the bearing capacity of shallow foundations. The correlation coefficients between the experimental and predicted bearing capacity values are equal to 0.95 and 0.96 for the best LGP models. Moreover, the derived models reach a notably better prediction performance than the traditional equations.

关键词： Rock mass properties Ultimate bearing capacity Shallow foundation Prediction Evolutionary computation Linear genetic programming

New insight into prediction of phase behavior of natural gas hydrate by different cubic equations of state coupled with various mixing rules

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Petroleum Science 2017年第4期14卷 780-790页

作者： amir hossein Saeedi Dehaghani Deparlment of Petroleum Engineering Faculty of Chemical EngineeringTarbiat Modares UniversityTehranlran

Progress in hydrate thermodynamic study necessitates robust and fast models to be incorporated in reservoir simulation softwares. However, numerous models presented in the literature makes selection of the best,proper predictive model a cumbersome task. It is of industrial interest to make use of cubic equations of state(EOS) for modeling hydrate equilibria. In this regard, this study focuses on evaluation of three common EOSs including Peng–Robinson, Soave–Redlich–Kwong and Valderrama–Patel–Teja coupled with van der Waals and Platteeuw theory to predict hydrate P–T equilibrium of a real natural gas sample. Each EOS was accompanied with three mixing rules, including van der Waals(vd W),Avlonitis non-density dependent(ANDD) and general nonquadratic(GNQ). The prediction of cubic EOSs was in sufficient agreement with experimental data and with overall AARD% of less than unity. In addition, PR plus ANDD proved to be the most accurate model in this study for prediction of hydrate equilibria with AARD% of *** was observed that the accuracy of cubic EOSs studied in this paper depends on mixing rule coupled with them,especially at high-pressure conditions. Lastly, the present study does not include any adjustable parameter to be correlated with hydrate phase equilibrium data.

关键词： Gas Hydrate Cubic equation of state Mixing rule Thermodynamic modeling

Enhancing the Robustness of Visual Object Tracking via Style Transfer

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Computers, Materials & Continua 2022年第1期70卷 981-997页

作者： Abdollah amirkhani amir hossein Barshooi amir Ebrahimi School of Automotive Engineering Iran University of Science and TechnologyTehran16846-13114Iran School of Electrical Engineering and Computing The University of NewcastleCallaghan2308Australia

The performance and accuracy of computer vision systems are affected by noise in different *** numerous solutions and algorithms have been presented for dealing with every type of noise,a comprehensive technique that can cover all the diverse noises and mitigate their damaging effects on the performance and precision of various systems is still *** this paper,we have focused on the stability and robustness of one computer vision branch(i.e.,visual object tracking).We have demonstrated that,without imposing a heavy computational load on a model or changing its algorithms,the drop in the performance and accuracy of a system when it is exposed to an unseen noise-laden test dataset can be prevented by simply applying the style transfer technique on the train dataset and training the model with a combination of these and the original untrained *** verify our proposed approach,it is applied on a generic object tracker by using regression *** method’s validity is confirmed by testing it on an exclusive benchmark comprising 50 image sequences,with each sequence containing 15 types of noise at five different intensity *** OPE curves obtained show a 40%increase in the robustness of the proposed object tracker against noise,compared to the other trackers considered.

关键词： Style transfer visual object tracking robustness corruption

Chaos detection and control in a typical power system

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Chinese Physics B 2013年第1期22卷 119-123页

作者： hossein Gholizadeh amir Hassannia Azita Azarfar Faculty of Electrical & Robotic Engineering Shahrood University of Technology

In this paper, a new chaotic system is introduced. The proposed system is a conventional power network that demonstrates a chaotic behavior under special operating conditions. Some features such as Lyapunov exponents and a strange attractor show the chaotic behavior of the system, which decreases the system performance. Two different controllers are proposed to control the chaotic system. The first one is a nonlinear conventional controller that is simple and easy to construct, but the second one is developed based on the finite time control theory and optimized for faster control. A MATLAB-based simulation verifies the results.

关键词： chaos detection chaos control finite time control theory synchronous generator

Weak gravitational lensing of quantum perturbed lukewarm black holes and cosmological constant effect

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Research in Astronomy and Astrophysics 2017年第6期17卷 17-36页

作者： hossein Ghaffarnejad Mojtaba amir Mojahedi Faculty of Physics Semnan University Semnan 35131-19111 Iran

The aim of the paper is to study weak gravitational lensing of quantum （perturbed） and classical lukewarm black holes （QLBHs and CLBHs respectively） in the presence of cosmological parameter A. We apply a numerical method to evaluate the deflection angle of bending light rays, image locations θ of sample sourceβ = π- 4, and corresponding magnifications μ. There are no obtained real values for Einstein ring locations θE（β = 0） for CLBHs but we calculate them for QLBHs. As an experimental test of our calculations, we choose mass M of 60 types of the most massive observed galactic black holes acting as a gravitational lens and study quantum matter field effects on the angle of bending light rays in the presence of cosmological constant effects. We calculate locations of non-relativistic images and corresponding magnifications. Numerical diagrams show that the quantum matter effects cause absolute values of the quantum deflection angle to be reduced with respect to the classical ones. The sign of the quantum deflection angle is changed with respect to the classical values in the presence of the cosmological constant. This means dominance of the anti-gravity counterpart of the cosmological horizon on the angle of bending light rays with respect to absorbing effects of 60 local types of the most massive observed black holes. Variations of the image positions and magnifications are negligible when increasing dimensionless cosmological constant ∈ = 16AM2 /2The deflection angle takes positive （negative） values for CLBHs （QLBHs） and they decrease very fast （slowly） by increasing the closest distance x0 of bending light ray and/or dimensionless cosmological parameter for sample giant black holes with 0.001 〈 ∈ 〈 0.01.

关键词： gravitational lensing weak - strong - micro - stars black holes

Removal of Reactive Red 198 from aqueous solution by combined method multi-walled carbon nanotubes and zero-valent iron:Equilibrium,kinetics,and thermodynamic

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Chinese Journal of Chemical Engineering 2016年第10期24卷 1448-1455页

作者： Sudabeh Pourfakari Nader Yousefi amir hossein Mahvi Department of Environmental Health Engineering School of HealthShiraz University of Medical SdencesShirazIran Department of Environmental Health Engineering School of Public HealthTehran University of Medical SciencesTehranIran Center for Solid Waste Research Institute for Environmental ResearchTehran University of Medical SciencesTehranIran National Institute of Health Research Tehran University of Medical SciencesTehranIran

Dyes often include toxic, carcinogenic compounds and are harmful to humans＇ health. Therefore, removal of dyes from textile industw wastewater is essential. The present study aimed to evaluate the efficiency of the combination of zero valent iron （ZVI） powder and multi-walled carbon nanotubes （MWCNTs） in the removal of Reactive Red 198 （RR198） dye from aqueous solution. This applied research was performed in a batch system in the laboratory scale. This study investigated the effect of various factors influencing dye removal, including contact time, pH, adsorbent dose, iron powder dose, initial dye concentration, and temperature. The equilibrium adsorption data were analyzed using three common adsorption models： Langmuir, Freundlich and Temkin. Besides, kinetic and thermodynamic parameters were used to establish the adsorption mechanism. The results showed, in pH = 3, contact time = 100 min, ZVI dose = 5000 mg· L- 1, and MWCNTs dose = 600 mg· L- 1 in 100 mg· L- 1 dye concentration, the adsorption efficiency increased to 99.16%. Also, adsorption kinetics was best described by the pseudo-second-order model. Equilibrium data fitted well with the Freundlich isotherm （R2 = 0.99）. The negative values of AGo and the positive value of △H0 （91.76） indicate that the RR198 adsorption process is spontaneous and endothermic. According to the results, the combination of MWCNTs and ZVI was highly efficient in the removal of azo dyes.

关键词： Reactive Red 198 MWCNTs Adsorption ZVI Dye

Processing of nanostructured metallic matrix composites by a modified accumulative roll bonding method with structural and mechanical considerations

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 951-956页

作者： amir hossein Yaghtin Erfan Salahinejad Ali Khosravifard Department of Materials Science and Engineering(Shiraz Branch) Islamic Azad UniversityShiraz 71955Iran Department of Materials Science and Engineering School of EngineeringShiraz UniversityShiraz ***Iran

Particulate reinforced metallic matrix composites have attracted considerable attention due to their lightweight, high strength, high specific modulus, and good wear resistance. A1/B4C composite strips were produced in this work by a modified accumulative roll bonding process where the strips were rotated 90° around the normal direction between successive passes. Transmission electron microscopy and X-ray diffraction analyses reveal the development of nanostructures in the Al matrix after seven passes. It is found that the B4C reinforcement distribution in the matrix is improved by progression of the process. Additionally, the tensile yield strength and elongation of the processed materials are increased with the increase of passes.

关键词： metallic matrix composites particle reinforced composites nanostructures aluminum boron carbide roll bonding tensile properties