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Chinese Journal of Polymer Science 2014年第5期32卷 587-594页

作者： nasser Goudarzi M.Arab Chamjangali A.h.Amin Faculty of Chemistry Shahrood University of Technology

In this work, some chemometrics methods are applied for the modeling and prediction of the hildebrand solubility parameter of some polymers. A genetic algorithm （GA） method is designed for the selection of variables to construct two models using the multiple linear regression （MLR） and least square-support vector machine （LS-SVM） methods in order to predict the hildebrand solubility parameter. The MLR method is used to build a linear relationship between the molecular descriptors and the hildebrand solubility parameter for these compounds. Then the LS-SVM method is utilized to construct the non-linear quantitative structure-activity relationship （QSAR） models. The results obtained using the LS-SVM method are then compared with those obtained for the MLR method; it was revealed that the LS-SVM model was much better than the MLR one. The root-mean-square errors of the training set and the test set for the LS-SVM model were 0.2912 and 0.2427, and the correlation coefficients were 0.9662 and 0.9518, respectively. This paper provides a new and effective method for predicting the hildebrand solubility parameter for some polymers, and also reveals that the LS-SVM method can be used as a powerful chemometrics tool for the quantitative structure-property relationship （QSPR） studies.

关键词： hildebrand solubility parameter Least square-support vector machine (LS-SVM) Quantitative structure- property relationship (QSPR) Multiple linear regression (MLR) Genetic algorithm (GA).

Geometric Phase of a Coupled System

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Communications in Theoretical Physics 2004年第5X期42卷 672-674页

作者： h.S.abdel-Aziz MathematicsDepartment FacultyofScienceSouthValleyUniversitySohagEgypt

In this contribution, my main attention is paid to the study of the geometric phase ora two-level *** expansion of the eigenvalue and analytic information are obtained. The results are illustrated with an application ... 详细信息

关键词：几何相位二平面偏微分方程量子论

Some Geometric Invariants of Pseudo-Spherical Evolutes in the hyperbolic 3-Space

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Computers, Materials & Continua 2018年第12期57卷 389-415页

作者： h.S.abdel-Aziz M.Khalifa Saad A.A.abdel-Salam Mathematics Department Faculty of ScienceSohag University82524SohagEgypt Mathematics Department Faculty of ScienceIslamic University of Madinah170 El-MadinahKSA

In this paper,we study the pseudo-spherical evolutes of curves in three dimensional hyperbolic *** use techniques from singularity theory to investigate the singularities of pseudo-spherical evolutes and establish some relationships between singularities of these curves and geometric invariants of curves under the action of the Lorentz ***,we defray with illustration some computational examples in support our main results.

关键词： Pseudo-spherical evolutes evolute curves hyperbolic 3-space

SYNThESIS, ChARACTERIZATION AND SPECTROSCOPIC INVESTIGATION OF PYRAZINOPORPhYRAZINE NETWORK POLYMER-SUPPORTED METAL (Ⅱ)-BASED CATALYSTS

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Chinese Journal of Polymer Science 2013年第2期31卷 242-250页

作者： h.h. abdel-Razik B.h. Asghar E. Kenawy Chemistry Department Faculty of Science Mansoura University Chemistry Department Faculty of Science Taif University Chemistry Department Faculty of Applied Sciences Umm Al-Qura University Chemistry Department Polymer Research Group Faculty of Science Tanta University

Chloranil through condensation reaction with vicinal diamine such as diaminomaleonitrile produced heterocyclic monomer, p-benzoquinonebis[2,3-b; 2＇,3＇-b＇]pyrazine-5,6-dinitrile. The tetranitrile monomer was cyclo-tetramerised using lithium/pentanol and acetic acid affording the corresponding tetrap-benzoquinone bis[2,3-b; 2＇,3＇-b＇]pyrazinoporphyrazine）]- based network polymer （2h-Pz）. The tetranitril monomer was cyclo-tetramerised using metal salt and quinoline affording the corresponding porphyrazinato-metal II-based network polymers （M-Pz）, M = Co, Ni or Cu. Elemental analytical results, IR and NMR spectral data of the prepared molecules are consistent with their assigned formulations. Molecular masses and metal contents of the synthesized polymers proved to be of high molecular masses which confirm the efficiency of tetramerization polymerization and complexation reactions. The prepared pyrazinoporphyrazines were used as efficient catalysts for the oxidation of thiophenol and benzylthiol to their disulfides in the presence of air atmosphere. The results of oxidation of thiophenol and benzylthiol show that after 15 min the maximum yield of the corresponding disulfides reached 95%, 91%, respectively.

关键词： Pyrazinoporphyrazine Polymer-supported metal (II)-based catalysts Chloranil.

A stochastic based approach for a new site classification method:application to the Algerian seismic code

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Earthquake Engineering and Engineering Vibration 2015年第4期14卷 663-681页

作者： Mohamed Beneldjouzi nasser Laouami Civil Engineering Faculty University of Sciences and Technology Houari Boumediene Earthquake Engineering Applied Research Center (CGS)

Building codes have widely considered the shear wave velocity to make a reliable subsoil seismic classification, based on the knowledge of the mechanical properties of material deposits down to bedrock. This approach has limitations because geophysical data are often very expensive to obtain. Recently, other alternatives have been proposed based on measurements of background noise and estimation of the h/V amplification curve. however, the use of this technique needs a regulatory framework before it can become a realistic site classification procedure. This paper proposes a new formulation for characterizing design sites in accordance with the Algerian seismic building code (RPA99/ver.2003), through transfer functions, by following a stochastic approach combined to a statistical study. For each soil type, the deterministic calculation of the average transfer function is performed over a wide sample of 1-D soil profiles, where the average shear wave (S-W) velocity, Vs, in soil layers is simulated using random field theory. Average transfer functions are also used to calculate average site factors and normalized acceleration response spectra to highlight the amplification potential of each site type, since frequency content of the transfer function is significantly similar to that of the h/V amplification curve. Comparison is done with the RPA99/ver.2003 and Eurocode8 (EC8) design response spectra, respectively. In the absence of geophysical data, the proposed classification approach together with micro-tremor measures can be used toward a better soil classification.

关键词： random field transfer function soil classification RPA99/ ver. 2003 EC8 site factor response spectrum

On the Relationship between Climatic Variables and Pressure Systems over Saudi Arabia in the Winter Season

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Advances in Atmospheric Sciences 2015年第5期32卷 690-703页

作者： h.M.hASANEAN h.abdel BASSET M.A.A.hUSSEIN Department of Meteorology Faculty of Meteorology Environment and Arid Land AgricultureKing Abdulaziz University Department of Meteorology and Astronomy Faculty of Science Al-Azhar University

The synoptic circulation over Saudi Arabia is complicated and frequently governed by the effect of large-scale pressure systems. In this work, we used NCEP–NCAR global data to illustrate the relationship between climatic variables and the main pressure systems that affect the weather and climate of Saudi Arabia, and also to investigate the influence of these pressure systems on surface air temperature（SAT） and rainfall over the region in the winter season. It was found that there are two primary patterns of pressure that influence the weather and climate of Saudi Arabia. The first occurs in cases of a strengthening Subtropical high（Sub h）, a weakening Siberian high（Sib h）, a deepening of the Icelandic Low（Ice L）, or a weakening of the Sudanese Low（Sud L）. During this pattern, the Sub h combines with the Sib h and an obvious increase of sea level pressure（SLP） occurs over southern European, the Mediterranean, North Africa, and the Middle East. This belt of high pressure prevents interaction between midlatitude and extratropical systems, which leads to a decrease in the SAT,relative humidity（Rh） and rainfall over Saudi Arabia. The second pattern occurs in association with a weakening of the Sub h, a strengthening of the Sib h, a weakening of the Ice L, or a deepening of the Sud L. The pattern arising in this case leads to an interaction between two different air masses： the first（cold moist） air mass is associated with the Mediterranean depression travelling from west to east, while the second（warm moist） air mass is associated with the northward oscillation of the Sud L and its inverted V-shape trough. The interaction between these two air masses increases the SAT, Rh and the probability of rainfall over Saudi Arabia, especially over the northwest and northeast regions.

关键词： climatic variables pressure system surface air temperature rainfall relative humidity Saudi Arabia

On Special Curves According to Darboux Frame in the Three Dimensional Lorentz Space

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Computers, Materials & Continua 2018年第3期54卷 229-249页

作者： h.S.abdel-Aziz M.Khalifa Saad Math.Dept. Faculty of ScienceSohag University82524 SohagEgypt. Math.Dept. Faculty of ScienceIslamic University of Madinah170 El MadinahKSA

In the light of great importance of curves and their frames in many differentbranches of science, especially differential geometry as well as geometric properties andthe uses in various fields, we are interested here to study a special kind of curves calledSmarandache curves in Lorentz 3-space. Then, we present some characterizations for thesecurves and calculate their Darboux invariants. Moreover, we classify TP, TU, PU andTPU-Smarandache curves of a spacelike curve according to the causal character of thevector, curve and surface used in the study. Besides, we give some of differential geometricproperties and important relations between that curves. Finally, to demonstrate ourtheoretical results a computational example is given with graph.

关键词： Smarandache curves spacelike curve timelike surface Darboux frame

The impact of cold atmospheric pressure plasma jet on seed germination and seedlings growth of fenugreek(Trigonella foenum-graecum)

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Plasma Science and Technology 2019年第10期21卷 61-72页

作者： Sahar A FADhLALMAWLA abdel-Aleam h MOhAMED Jamal Q M ALMARAShI Tahar BOUTRAA Physics Department College of ScienceTaibah UniversityAl-Madinah Al-Munawarah 42353Saudi Arabia Physics Department Faculty of ScienceBeni-Suef UniversityBeni-Suef 52511Egypt Department of Biology College of SciencesUniversity of TaibahAl-Madinah Al-Munawarah 42353 Saudi Arabia

The effects of cold atmospheric-pressure plasma jet (CAPPJ) were investigated on germination and early seedling growth of fenugreek (Trigonella foenum-graecum L) seeds. A two-electrode argon CAPPJ system with and without an additional grounded electrode [accelerating grounded (AG) electrode] was used at different exposure times. After 16 h of observation, the germination rates increased by 4 and 7 times, without and with using an AG electrode, respectively, for 1 min of plasma exposure. An increase in shoot fresh weight was observed, especially at 10 min exposure time. A high dry weight of root and shoot at 1 min-AG exposure time was observed. The root:shoot ratio was lower in plasma-treated seedlings, compared with the control plants. The study found that the O-radical emission line (777.4 nm) enhanced 5 times, due to the presence of an AG electrode, which increased the axial electric field and led to the formation of more streamers. The three stated effects (O-radicals, enhancement of the electric field and streamers) could be the cause for the stimulation of seed germination and seedling growth parameters when using the CAPPJ. The scanning electron microscope images showed the etching of the seed surface layers, which was more pronounced when an AG electrode was applied. The results of the current study indicate that the germination rates increased due to the increase of O-radical concentration and the etching of the seed surfaces.

关键词： cold plasma fenugreek (Trigonella foenum-graecum) germination growth

Rational Design of T-Girders via Finite Element Method

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Journal of Marine Science and Application 2021年第2期20卷 302-316页

作者： Ahmed hammad Yehia abdel-nasser Mohamed Shama Department of Naval Architecture and Marine Engineering Faculty of EngineeringAlexandria UniversityAlex andria 21544Egypt

The main configuration of ship construction consists of standard and fabricated stiffening members,such as T-sections,which are commonly used in *** the welding process,the nonuniform heating and rapid cooling lead to welding imperfections such as out-of-plane distortion and residual *** to these imperfections,the fabricated structural members may not attain their design load,and removing these imperfections will require extra *** present work investigated controlling these imperfections at both the design and fabrication stages.A typical fabricated T-girder was selected to investigate the problem of these imperfections using double-sided welding.A numerical simulation based on finite element modeling(FEM) was used to investigate the effects of geometrical properties and welding sequence on the magnitude of the welding imperfections of the *** FEM results were validated with the experimental measurements of a double-sided fillet *** the design stage,the optimum geometry of the fabricated T-girder was determined based on the minimum steel weight and out-of-plane ***,regarding the fabrication stage,a parametric study with two variables(geometrical properties and welding sequence)was conducted to determine the optimum geometry and welding sequence based on the minimum welding out-of-plane *** the flange thickness and reducing the breadth while keeping the T-girder section modulus constant reduced the T-girder weight and out-of-plane *** welding produced a significant reduction in the out-of-plane distortion,while an insignificant increase in the compressive residual stress occurred.

关键词： Out-of-plane distortion Finite element modeling Welding residual stresses Fabricated T-girder Section modulus

Optimal operation of energy at hydrothermal power plants by simultaneous minimization of pollution and costs using improved ABC algorithm

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Frontiers in Energy 2015年第4期9卷 426-432页

作者： homayoun EBRAhIMIAN Bahman TAhERI nasser YOUSEFI Department of Engineering Ardabil Branch Islamic Azad University Ardabil 0451 Iran Young Researchers and Elite Club Ardabil Branch Islamic Azad University Ardabil 0451 Iran

The aim of this paper is simultaneous mini- mization of hydrothermal units to reach the best solution by employing an improved artificial bee colony （ABC） algorithm in a multi-objective function consisting of economic dispatch （ED） considering the valve-point effect and pollution function in power systems in view of the hot water of the hydro system. In this type of optimization problem, all practical constraints of units were taken into account as much as possible in order to comply with the reality. These constraints include the maximum and minimum output power of units, the constraints caused by the balance between supply and demand, the impact of pollution, water balance, uneven production curve con- sidering the valve-point effect and system losses. The proposed algorithm is applied on the studied system, and the obtained results indifferent operating conditions are analyzed. To investigate in various operating conditions, different load profiles in 12 h are taken into account. The obtained results are compared with those of the other methods including the genetfc algorithm （GA）, the Basu technique, and the improved genetic algorithm. Fast convergence is one of this improved algorithm features.

关键词： practical constraints of units pollution func-tion inlet steam valve up-ramp rate of units improvedABC algorithm