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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

Effect of synthesis solution pH of Co/γ-Al_2O_3 catalyst on its catalytic properties for methane conversion to syngas

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燃料化学学报 2018年第3期46卷 311-318页

作者： amir Mosayebi reza Abedini Department of Chemical Engineering Tafresh University Faculty of Chemical Engineering Babol Noshirvani University of Technology

The cobalt nanoparticles over γ-Al_2O_3 support were prepared via chemical reduction of CoCl_2·6H_2O using NaBH_4 with various values of pH in the range of 11. 92-13. 80. Synthesized catalysts were studied through X-ray diffraction( XRD),N_2 adsorption/desorption( BET),H_2-temperature programmed reduction( H_2-TPR),H_2-chemisorption,O_2 pulse titration and temperature programmed oxidation( TPO) methods. Obtained results exhibited the synthesis solution pH showed a significant influence on the activity and selectivity in partial oxidation of methane reaction. The methane conversion,CO selectivity and H_2 yield were enhanced by increasing of the synthesis solution pH. Compared to other catalysts,the catalyst that synthesized at pH of 13.80,showed a superior ability in syngas production with a H_2/CO ratio of near 2 and also a proper stability against deactivation during the partial oxidation of methane.

关键词：部分氧化 Co/-Al 2 O 3 nanoparticles 选择 pH 价值

CHARACTEIZATIONS OF WOVENT g-FRAMES AND WEAVING g-FRAMES IN HILBERT SPACESS AND C^(*)-MODULES

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Acta Mathematica Scientia 2023年第6期43卷 2471-2482页

作者： amir KHOSRAVI Mohammad reza FARMANI Faculty of Mathematical Sciences and Computer Kharazmi University599 Taleghani Ave.Tehran 15618Iran

In this paper,using Parseval frames we generalize Sun’s results to g-frames in Hilbert C^(*)-***,for g-frames in Hilbert spaces,we present some characterizations in terms of a family of frames,not only for orthonormal ***,we have a note about a comment and a relation in the proof of Proposition 5.3 in[*** et al.,On weaving g-frames for Hilbert spaces,Complex Analysis and Operator Theory,2020].Finally,we have some results for g-Riesz bases,woven and P-woven g-frames.

关键词： g-frame fusion frame woven frame Riesz basis g-Riesz basis

A 3D analytical model for vortex velocity field based on spiral streamline pattern

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Water Science and Engineering 2019年第3期12卷 244-252页

作者： Maryam Azarpira amir reza Zarrati Department of Civil and Environmental Engineering Amirkabir University of Technology

Vortices that develop over intakes are a hazardous hydraulic *** this study, a 3D model was developed to study the flow field in air-core *** model is based on the spiral pattern of streamlines and the analytical solution of the momentum and continuity equations for deriving the three components of *** model provides equations for free surface profiles and 3D patterns of the ***, a new relationship was suggested for calculating effective viscosity and its distribution across the vortex flow *** performance of the proposed analytical model was compared with existing experimental data and the results of previous analytical *** outcomes indicated that the proposed model could predict characteristics of the vortex flow with good accuracy.

关键词： Air-core vortices Analytical model Velocity distribution Spiral streamlines Free surface profile

Evaluation on the Two Filling Functions for the Recovery of Forest Information in Mountainous Shadows on Landsat ETM + Image

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Journal of Mountain Science 2011年第3期8卷 414-426页

作者： SHAHTAHMASSEBI amir reza MOORE Nathan Institute of Agriculture Remote Sensing and Information Technology Zhejiang University Key Laboratory of Agricultural Remote Sensing and Information System of Zhejiang Province Department of Geography Michigan State University

In general,topographic shadow may reduce performance of forest mapping over mountainous regions in remotely sensed *** this paper,information in shadow was synthesized by using two filling techniques,namely,roifill and imfill,in order to improve the accuracy of forest mapping over mountainous *** two methods were applied to Landsat Enhanced Thematic Mapper (ETM +) multispectral image from Dong Yang County,Zhejiang Province,*** performance of these methods was compared with two conventional techniques,including cosine correction and multisource *** results showed that by applying filling approaches,average overall accuracy of classification was improved by 14 ***,through conventional methods this value increased only by 9 *** results also revealed that estimated forest area on the basis of shadow-corrected images by 'roifill' technique was much closer to the survey data compared to traditional *** from this finding,our finding indicated that topographic shadow was an accentuated problem in medium resolution images such as Landsat ETM+ over mountainous regions.

关键词： Shadow Imfill: Roifill: Landsat ETM+

Fabrication of a Highly Sensitive Hydrazine Electrochemical Sensor Based on Bimetallic Au-Pt Hybrid Nanocomposite onto Modified Electrode

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Nano-Micro Letters 2010年第4期2卷 296-305页

作者： Azadeh Azadbakht amir reza Abbasi Department of Chemistry Faculty of Basic ScienceIslamic Azad UniversityKhorramabad Branch Faculty of Science and Engineering Islamic Azad UniversityDoroud Branch

In this research a novel nickel complex was used as electrocatalyst for electrooxidation of hydrazine.A nano-structured nickel-complex was electrodeposited on a bimetallic Au-Pt inorganic-organic hybrid nanocomposite modified *** electrode possesses a three-dimensional(3D) porous network nanoarchitecture,in which the bimetallic Au-Pt NPs serving as metal nanoparticle based microelectrode ensembles are distributed in the matrix of interlaced 3,3′,5,5′-Tetramethylbenzidine(TMB) organic nanofibers(NFs).Surface structure and composition of the sensor was characterized by scanning electron *** oxidation of hydrazine on the surface of modified electrode was investigated with cyclic voltammetry *** results showed that the nickelcomplex films displayed excellent electrochemical catalytic activities towards hydrazine *** hydrodynamic amperometry at rotating modified electrode at constant potential versus reference electrode was used for detection of *** optimized conditions the calibration plots were linear in the concentration range of 0.2-85 μM and detection limit was found to be 0.1 μ*** modified electrode exhibited reproducible behavior and a high level stability during the electrochemical experiments,making it particularly suitable for the analytical purposes.

关键词： 3,3′,5,5′-Tetramethylbenzidine Hydrazine Nanocomposite electrodes Nanofiber

Statistical design and kinetic and thermodynamic studies of Ni(Ⅱ) adsorption on bentonite

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Journal of Central South University 2017年第7期24卷 1529-1536页

作者： Bahareh Sadeghalvad amir reza Azadmehr Hassan Motevalian Department of Mining&Metallurgical Engineering Amirkabir University of TechnologyTehranIran

The adsorption of the bentonite toward Ni(II) from aqueous solution was studied to obtain optimum conditions,equilibrium model,thermodynamic and kinetic *** method was used to evaluate maximum amount of adsorbed Ni(II).In this work,p H of solution during stirring,contact time,initial Ni(II) concentration,particle size of bentonite and amount of bentonite were considered as effective parameters which should be *** increase of temperature has negative effect on the Ni(II) *** equilibrium data were correlated well with Freundlich and Dubinin–Radushkevich isotherm models the correlation coefficients of which are(R^2) 0.994 and 0.971,*** model indicates heterogeneous and chemical absorption or ion exchange *** values of thermodynamic parameters such as ΔH°,ΔS° and ΔG° of nickel adsorption reveal that it is a spontaneous,exothermic and associative *** experimental data fit the pseudo-second-order kinetic very well with correlation coefficient(R^2) more than 0.995.

关键词： bentonite adsorption experimental design optimum condition equilibrium

How much would silica nanoparticles enhance the performance of low-salinity water flooding?

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Petroleum Science 2019年第3期16卷 591-605页

作者： amir Hossein Saeedi Dehaghani reza Daneshfar Department of Petroleum Engineering Faculty of Chemical Engineering Tarbiat Modares University Jalal Ale Ahmad Highway Gisha Bridge Tehran Iran Department of Petroleum Engineering Ahwaz Faculty of Petroleum Engineering Petroleum University of Technology (PUT) Ahwaz Iran

Nanofluids and low-salinity water(LSW)flooding are two novel techniques for enhanced oil *** some efforts on investigating benefits of each method,the pros and cons of their combined application need to be *** work sheds light on performance of LSW augmented with nanoparticles through examining wettability alteration and the amount of incremental oil recovery during the displacement *** this end,nanofluids were prepared by dispersing silica nanoparticles(0.1 wt%,0.25 wt%,0.5 wt% and 0.75 wt%)in 2,10,20 and 100 times diluted samples of Persian Gulf *** angle measurements revealed a crucial role of temperature,where no wettability alteration occurred up to 80 ℃.Also,an optimum wettability state(with contact angle 22°)was detected with a 20 times diluted sample of seawater augmented with 0.25 wt% silica ***,extreme dilution(herein 100 times)will be of no *** micromodel flooding,it was found that in an oil-wet condition,a combination of silica nanoparticles dispersed in 20 times diluted brine had the highest displacement efficiency compared to silica nanofluids prepared with deionized ***,by comparing oil recoveries in both water-and oil-wet micromodels,it was concluded that nanoparticles could enhance applicability of LSW via strengthening wettability alteration toward a favorable state and improving the sweep efficiency.

关键词： Low-salinity water Silica nanoparticles Low-salinity nanofluid Micromodel Enhanced oil recovery Wettability alteration

Neotectonics of the Avaj region(NW Iran): left-lateral strike-slip and range-parallel reverse faults

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Journal of Mountain Science 2020年第4期17卷 838-850页

作者： reza ALIPOOR amir Hossein SADR Sahar GHAMARIAN Geology Department Faculty of Basic ScienceBu-Ali Sina UniversityHamedan 009881Iran

The aim of this study is the geomorphological analysis of neotectonic deformation in the Avaj region in the NW part of the Iranian Plateau. We use observations from detailed field surveys and the analysis of digital elevation model(DEM) and satellite images(Landsat-7 ETM+, 30-m resolution) to explore a new E-W trending strike-slip fault system in the study area. The major active faults of the Avaj region are the NW-SE trending Avaj and Hassanabad fault zones. The Avaj Fault is a SWdipping reverse fault with a transport toward NE and the Hassanabad Fault is a NE-dipping reverse fault that has moved Paleozoic rocks over Cenozoic sedimentary units. Moreover, there are some E-W trending left-lateral strike-slip faults which cut Late Quaternary deposits. The relationship between the NW-SE and E-W faults indicates that the slip at the termination of the NW-SE faults changes from reverse to left-lateral strike-slip faults. The activity of the left-lateral faults has formed a series of offsets and displacements in drainage paths. These left-lateral faults probably initiated in 5±2 Ma because of the convergence between the Central Iran and the South Caspian blocks.

关键词： Active tectonic Offset Earthquake Geomorphology Avaj Fault South Caspian