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Chinese Journal of Polymer Science 2006年第5期24卷 449-456页

作者： arfat anis A.K. Banthia S. Mondal A.K. Thakur Materials Science Centre Indian Institute of TechnologyKharagpur 721302India Department of Physics & Meteorology Indian Institute of TechnologyKharagpur 721302India

Hybrid proton conducting membranes of poly（vinyl alcohol）（PVA） and phosphomolybdic acid （PMA） were prepared by solution casting method. The effect of PMA doping and PVA crosslinking density on the membrane properties and proton conductivity were investigated. The crosslinking reaction between the hydroxyl group of PVA and the aldehyde group of glutaraldehyde （GA） was characterized by IR spectroscopy. Proton conductivity of the membranes increases with an increase in concentration of the doped PMA and also with an increase in crosslinking density of the membranes. Proton conductivity results indicate that a significant amount of PMA was maintained in the membranes even after several hours of immersion in water. A maximum conductivity of 0.0101 S cm^-1 was obtained for the membrane with 33.3 wt% PMA and crosslinking density of 5.825 mol%. X-ray diffraction studies were carried out to investigate the influence of PMA doping and crosslinking density on the nature of the membranes. These properties make them very good candidates for polymer electrolyte membranes for direct methanol fuel cell application.

关键词： Polymer electrolyte membranes Proton conductor Phosphomolybdic acid Crosslinked PVA membranes.

A Reframed Watermark Extraction Approach Using the ABC Algorithm

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Chinese Journal of Electronics 2021年第4期30卷 736-742页

作者： KRICHA anis KRICHA Zied SAKLY anis LATIS Lab National School of Engineers of Sousse University of Sousse National School of Engineers of Monastir University of Monastir Higher Institute of Applied Science and Technology of Sousse University of Sousse ESIR Research Unit National School of Engineers of Monastir University of Monastir

The fast development and the rapid spread of information technology have raised the issue of digitalimage copyright protection, which was mostly addressed through robust watermarking. To ensure the survival of the watermark after attacks, most works have been making use of an additional step at the embedding phase,and by so making the scheme unsuitable for real-time implementation. However, to be effective and secure, it is recommended to combine the watermarking algorithm and the capture sensor in one device. In this paper, we brought the extra stage to the detection side. We firstly studied the effect of some signal processing operations on a watermarked image, then we proposed a general model for watermark extraction whose parameters were determined using the artificial bee colony. The efficacy of the proposed method was validated by comparing its robustness with two state-of-art schemes focusing on the watermark extraction.

关键词： Robust watermarking Artificial bee colony(ABC) Adaptive extraction

Discrete-Time Chaotic Systems Synchronization Based on Vector Norms Approach

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Journal of Systems Science & Complexity 2017年第5期30卷 1012-1026页

作者： GAM Rihab SAKLY anis Industrial Systems Study and Renewable Energy(ESIER) the National Engineering School of Monastir(ENIM)University of Monastirav.Ibn El jazzar Skanes 5019Tunisia

Suitable stabilization conditions obtained for continuous chaotic systems are generalized to discrete-time chaotic systems. The proposed approach, leading to these conditions for complete synchronization is based on the use of state feedback and aggregation techniques for stability studies associated with the arrow form matrix for system description. The results are successfully applied for two identical discrete-time hyper chaotic Henon maps with different orders and also for non-identical discrete-time chaotic systems with same order namely the Lozi and the Ushio maps.

关键词： Aggregation techniques arrow form matrix different order discrete-time chaotic systems synchronization.

On the Stability Analysis of Switched Nonlinear Systems with Time Varying Delay Under Arbitrary Switching

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Journal of Systems Science & Complexity 2017年第2期30卷 329-346页

作者： KERMANI Marwen SAKLY anis Research Unit of Industrial Systems Study and Renewable Energy(ESIER) National Engineering School of MonastirIbn El JazzarSkaness5019University of MonastirTunisia

This paper addresses the stability problem for a class of switched nonlinear time varying delay systems modeled by delay differential equations. By transforming the system representation under the arrow form and using a new constructed Lyapunov function,the aggregation techniques,the Borne-Gentina practical stability criterion associated with the properties, new delay-independent stability conditions of the considered systems are established. Compared with the existing results in this area, the obtained result is explicit, simple to use and allows us to avoid the problem of searching a common Lyapunov function. Finally, an example is provided, with numerical simulations,to demonstrate the effectiveness of the proposed method.

关键词： Arbitrary switching arrow form statepunov function continuous-time switched nonlinearstability.matrix Borne-Gentina criterion common Lya-time varying delay systems global asymptotic

Performance evaluation of hybrid constructed wetlands for the treatment of municipal wastewater in developing countries

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1717-1724页

作者： Sajjad Haydar Mehwish anis Misbah Afaq Institute of Environmental Engineering&Research(IEER) University of Engineering&Technology(UET)LahorePakistan

In developing countries,high cost of conventional wastewater treatment is a major hindrance in its *** wetlands(CWs)offer low-cost and effective solution to this *** current study aimed to evaluate an innovative maneuver of CWs *** flow constructed wetlands(HCWs)for municipal wastewater(MWW).The HCWs included two lab scale CWs;one horizontal and one vertical,in *** plant species were *** were operated in both,batch and continuous *** mode was used to(1)optimize detention time and(2)find pollutants removal *** operation(at batch optimized retention time)was carried out for the evaluation of mass removal rate,r(g·m-2·d-1),volumetric rate constant,Kv(per day)and areal rate constant,Ka(m·d-1).Among two local plants tested,Pistia stratiotes gave better removal efficiency than *** detention time in HCWs was found to be 8 days(4+4 each).The optimum COD,BOD,TSS,TKN and P removal observed for Pistia stratiotes planted HCWs was 80%,84%,82%,71%and88%*** standards for COD,BOD and TSS were met at optimum *** values of Kaand Kv demonstrated that more removal occurred in vertical flow as compared to horizontal flow CW.

关键词： Constructed wetlands Municipal wastewater Hybrid Pistia Typha Batch mode Continuous mode

An Analogy of Clifford Decomposition Theorem for Abel-Grassmann Groupoids

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Algebra Colloquium 2014年第2期21卷 347-353页

作者： Madad Khan Saima anis Department of Mathematics COMSATS Institute of Information Technology Abbottabad Pakistan

Let S be an inverse AG-groupoid （Abel-Grassmann groupoid） and define a relation γ on S by aγb if and only if there exist some positive integers n and m such that bm∈ （Sa）S and an∈ （Sb）S. We prove that S/γ is a maximal semilattice homomorphic image of S. Thus, every inverse AG-groupoid S is uniquely expressible as a semilattice Y of some Archimedean inverse AG-groupoids Sα （α∈ Y）. Our result can be regarded as an analogy of the well known Clifford theorem in semigroups for AG-groupoids.

关键词： inverse AG**-groupoid invertive law medial law

Endoscopic mucosal resection in the upper gastrointestinal tract

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World Journal of Gastroenterology 2008年第13期14卷 1984-1989页

作者： anis Ahmadi Peter Draganov Division Gastroenterology Hepatology and Nutrition University of Florida Gainesville Florida 32610 United States

Endoscopic mucosal resection （EMR） is a technique used to locally excise lesions confined to the mucosa. Its main role is the treatment of advanced dysplasia and early gastrointestinal cancers. EMR was originally described as a therapy for early gastric cancer. Recently its use has expanded as a therapeutic option for ampullary masses, colorectal cancer, and large colorectal polyps. In the Western world, the predominant indication for EMR in the upper gastrointestinal tract is the staging and treatment of advance dysplasia and early neoplasia in Barrett＇s esophagus. This review will describe the basis, indications, techniques, and complications of EMR, and its role in the management of Barrett＇s esophagus.

关键词： Endoscopic mucosal resection Mucosal resection Barrett's esophagus Barrett's dysplasia Therapeutic endoscopy

Iterative Selection of GOB Poles in the Context of System Modeling

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International Journal of Automation and computing 2019年第1期16卷 102-111页

作者： anis Khouaja Hassani Messaoud High Institute of Applied Science and Technology National Engineering School of Monastir (ENIM)

This paper is concerned with the problem of system identification using expansions on generalized orthonormal bases(GOB). Three algorithms are proposed to optimize the poles of such a basis. The first two algorithms determine a GOB with optimal real poles while the third one determines a GOB with optimal real and complex poles. These algorithms are based on the estimation of the dominant mode associated with a residual signal obtained by iteratively filtering the output of the process to be modelled. These algorithms are iterative and based on the quadratic error between the linear process output and the GOB based model output. They present the advantage to be very simple to implement. No numerical optimization technique is needed, and in consequence there is no problem of local minima as is the case for other algorithms in the literature. The convergence of the proposed algorithms is proved by demonstrating that the modeling quadratic error between the process output and the GOB based model is decreasing at each iteration of the algorithm. The performance of the proposed pole selection algorithms are based on the quadratic error criteria and illustrated by means of simulation results.

关键词： Generalized orthonormal bases(GOB) Laguerre functions Kautz functions pole estimation modelling identification

Coset Diagram for the Action of Picard Group on Q（i, √3）

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Algebra Colloquium 2016年第1期23卷 33-44页

作者： Qaiser Mushtaq Saima anis Department of Mathematics Quaid-i-Azam University Islamabad Pakistan Department of Mathematics COMSATS Institute of Information Technology Abbottabad Pakistan

In this paper coset diagrams, propounded by Higman, are used to investigate the behavior of elements as words in orbits of the action of the Picard group F = PSL（2, Z[i]） on Q（i, √3）. Graphical interpretation of amalgamation of the components of F is also given. Some elements a＋b√3/c of Q（i, √3） and their conjugates a-b√3/c a c over Q（i） have different signs in the orbits of the biquadratic field Q（i, √3） when acted upon by F. Such real quadratic irrational numbers are called ambiguous numbers. It is shown that ambiguous numbers in these coset diagrams form a unique pattern. It is proved that there are a finite number of ambiguous numbers in an orbit Fa, and they form a closed path which is the only closed path in the orbit Гa. We also devise a procedure to obtain ambiguous numbers of the form a-b√3/c, where b is a positive integer.

关键词： Picard group biquadratic field coset diagrams and ambiguous numbers

On Semilattice Decomposition of an Abel–Grassmann’s Groupoid

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Acta Mathematica Sinica,English Series 2012年第7期28卷 1461-1468页

作者： Madad KHAN Saima anis Department of Mathematics COMSATS Institute of Information Technology

In this paper, we have decomposed an AG-groupoid. Let S be an AG-groupoid with left identity and a relation γ be defined on S as： aγb if and only if there exist positive integers m and n such that b^m∈E （Sa）S and a^n ∈ （Sb）S for all a and b in S. We have proved that S/γ is a maximal separative Semilattice homomorphic image of S. Every AG-groupoid S is uniquely expressible as a semilattice Y of archimedean AG-groupoids Sa （a∈ Y）. The semilattice Y is isomorphic to S/γ and the Sγ （a ∈ Y） are the equivalence classes of S mod V.

关键词： AG-groupoid invertive law medial law congruence