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Constrained bilinear control problem： Application to a cancer chemotherapy model

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International Journal of Biomathematics 2017年第4期10卷 189-209页

作者： e1 Hassan Zerrik Nihale e1 Boukhari MA CS Team Faculty of Sciences Moulay Ismail University Meknes Morocco

The aim of this paper is to investigate the optimal control problem for finite-dimensional bilinear systems and its application to a chemotherapy model. We characterize an opti- mal control that minimizes a quadratic cost functional in two cases of constrained admis- sible controls, then we give sufficient conditions for the uniqueness of such a control, and we derive useful algorithms for the computation of the optimal control. The established results are applied to a cancer chemotherapy bilinear model in order to simulate the opti- mal treatment protocol using two different approaches： one based on a limited instant toxicity, and the other on a limited cumulative toxicity along the therapy session.

关键词： Bilinear systems optimal control chemotherapy instant toxicity cumulativetoxicity.

A TRUST-ReGION ALGORITHM FOR SOLVING MINI-MAX PROBLeM

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Journal of Computational Mathematics 2018年第6期36卷 776-791页

作者： Bothina e1-Sobky Abdallah Abotahoun Department of Mathematics Alexandria University Alexandria Egypt

In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality constrained mini-max optimization problem into unconstrained optimization problem. A trust-region method is a well-accepted technique in constrained optimization to assure global convergence and is more robust when they deal with rounding errors. One of the advantages of trust-region method is that it does not require the objective function of the model to be convex. A global convergence analysis for the proposed algorithm is presented under some conditions. To show the efficiency of the algorithm numerical results for a number of test problems are reported.

关键词： Mini-max problem Active-set Multiplier method Trust-region Global con-vergence

A CONJUGATe GRADIeNT MeTHOD FOR DISCReTe-TIMe OUTPUT FeeDBACk CONTROL DeSIGN

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Journal of Computational Mathematics 2012年第3期30卷 279-297页

作者： e1-Sayed M.e. Mostafa Department of Mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, the discrete-time static output feedback control design problem is con- sidered. A nonlinear conjugate gradient method is analyzed and studied for solving an unconstrained matrix optimization problem that results from this optimal control prob- lem. In addition, through certain parametrization to the optimization problem an initial stabilizing static output feedback gain matrix is not required to start the conjugate gradi- ent method. Finally, the proposed algorithms are tested numerically through several test problems from the benchmark collection.

关键词： Output feedback control Nonlinear conjugate gradient methods Nonlinearprogramming.

Impact of the association between elevated oestradiol and low testosterone levels on erectile dysfunction severity

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Asian Journal of Andrology 2013年第4期15卷 492-496,I0007-I0008页

作者： Ahmed I e1-Sakka Department of Urology Suez Canal University 41111 Ismailia Egypt and AI-Noor Specialist Hospital Makkah PO Box 6251 Saudi Arabia

Our aim was to assess the impact of the association between elevated oestradiol （e2） and low testosterone （T） levels on erectile dysfunction （eD） severity. A total of 614 male patients with eD and a normal or low T level in association with normal or elevated e2 levels were enrolled. Patients underwent routine laboratory investigations in addition to measurements of total T, total e2, follicle-stimulating hormone （FSH）, luteinizing hormone （LH） and prolactin. We compared the responses to the erectile function domain, Q3 （achieving erection） and Q4 （maintaining erection） of the International Index for erectile Function （IIeF） score in patients with the following： normal T and e2 levels; low T level; low T level and elevated e2 level; and elevated e2 level. Of the patients included, 449 （73.1%） had normal T and e2 levels, 110 （17.9%） had a low T level, 36 （5.9%） had a low T level and an elevated e2 level, and 19 （3.1%） had an elevated e2 level. Increased eD severity was significantly associated with low T levels, elevated e2 levels, and both a low T level and an elevated e2 level. Additionally, the mean values of the eF-domain, Q3 and Q4 were significantly lower in patients with both a low T level and an elevated e2 level compared to patients with any condition alone. In conclusion, a low T level had the primary effect on erectile function; however, a concomitantly elevated e2 level had an additive impairment effect.

关键词： erectile dysfunction (eD) hypogonadism testosterone oestradiol

Periodicities in the emplacement of large igneous provinces through the Phanerozoic:Relations to ocean chemistry and marine biodiversity evolution

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Geoscience Frontiers 2013年第3期4卷 263-276页

作者： Andreas Prokoph Hafida e1 Bilali Richard ernst Speedstat 19 Langstrom CrescentOttawaON K1G 5J5Canada Carleton University Department of Earth SciencesHerzberg BuildingOttawaON KIS 5B6Canada Carleton University Department of Earth SciencesHerzberg BuildingOttawaON K1S 5B6Canada ernstGeosciences 43 Margrave AvenueOttawaON K1T 3Y2Canada

Large igneous provinces （LIPs） are considered a relevant cause for mass extinctions of marine life throughout earth＇s history. Their flood basalts and associated intrusions can cause significant release of SO4 and CO2 and consequently, cause major environmental disruptions. Here, we reconstruct the long-term periodic pattern of LIP emplacement and its impact on ocean chemistry and biodiversity from δ34Ssulfate of the last 520 Ma under particular consideration of the preservation limits of LIP records. A combination of cross-wavelet and other time-series analysis methods has been applied to quantify a potential chain of linkage between LIP emplacement periodicity, geochemical changes and the Phanerozoic marine genera record. We suggest a mantle plume cyclicity represented by LIP volumes （V） of V= （350-770） × 103km3sin（27πt/ 170 Ma）＋（300-650）× 103 km3 sin（2πt/64.5 Ma ＋ 2.3） for t= time in Ma. A shift from the 64.5 Ma to a weaker -28-35 Ma LIP cyclicity during the Jurassic contributes together with probably independent changes in the marine sulfur cycle to less ocean anoxia, and a general stabilization of ocean chemistry and increasing marine biodiversity throughout the last -135 Ma. The LIP cycle pattern is coherent with marine biodiversity fluctuations corresponding to a reduction of marine biodiversity of -120 genera/Ma at 600 x 103 km3 LIP eruption volume. The 62-65 Ma LIP cycle pattern as well as excursion in -34Ssulfate and marine genera reduction suggest a not-vet identified found LIP event at - 440-450 Ma.

关键词： Large igneous provinces Wavelet transform Sulfur isotope Mantle plume Marine biodiversity Periodicity

Origin and geochemistry of Pan-African granitoid rocks in the Gabal Um Shomer area,Southwestern Sinai,egypt

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Chinese Journal Of Geochemistry 2009年第2期28卷 125-135页

作者： e1-Tokhi M.M. Musallum A. Amin B.M. Geology Department College of ScienceUnited Arab Emirates UniversityUnited Arab Emirates

Geological, petrological and geochemical studies indicated that there are two distinct types of granitoid rocks: older quartz diorites to granodiorite assemblage and younger granitoids, the latter occurring in two phases. The older granitoids have a meta-aluminous chemistry and a calc-alkaline character, with high MgO, Fe2O3, TiO2, CaO, P2O5, Sr and low SiO2, k2O, and Rb. Their major and trace elements data, together with low 87Sr/ 86Sr ratios (0.7029±0.0008) are indicative of I-type affinities. The second- and third-phase granitoids range from calc-alkaline to alkaline, respectively. The second-phase granitoids have a peraluminous chemistry and high Sr, Ba, CaO, MgO, Al2O3 and Ti2O and low SiO2, k2O, Nb, Y and Rb relative to the third-phase granitoids. The corundum normative nature and field observations suggested that it was formed by partial melting of the lower crust. The third-phase granitoids are alkaline in nature and characterized by higher SiO2, Rb, Y, Nb and lower MgO, Sr and Ba values than the younger granitoids (phase Ⅱ). They are A-type granitoids which were generated from below or within the existing continental crust.

关键词：花岗岩类岩石地球化学西奈半岛过铝质花岗岩起源西南埃及石英闪长岩

Synthesis of Novel 3-Substituted PyridothienopyrimidineDerivatives with Biological evaluation as Antimicrobial Agents

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Chemical Research in Chinese Universities 2016年第6期32卷 967-972页

作者： Farag A. e1-essawy Nader M. Boshta Ayman k. eI-Sawaf Areal A. Nassar Mohamed S. khalafalah Preparatory Year Deanship Basic Science Department Prince Sattam Bin Abdulaziz University KSA Chemistry Department Faculty of Science Menoufia University Shebin EI-Koam Egypt Collage of Science and Humanitles Prince Sattam Bin Abdulaziz University KSA Faculty of education for Girls Prince Sattam Bin Abdulaziz University KSA

Novel 3-substituted pyridothienopyrimidine derivatives have been synthesized via the reaction of 2-{7,9-dimethyl-4-oxopyrido[3′,2′：4,5]thieno[3,2-d]pyrimidin-3（4H）-yl}acetohydrazide（5） with a variety of activereagents and chemicals. Structures of the newly synthesized compounds were established based on spectral *** resulting pyridothienopyrimidine derivatives were evaluated for their possible antimicrobial activity and some ofthem represent a new class of potentially antimicrobial compounds, especially compounds 9 and 18 which displayedthe highest activity against Gram-positive bacteria, Gram-negative bacteria, and Fungi in MIC range of 0.12--1.95 μg/mL.

关键词： Nitrogen-containing heterocycle Pyridothienopyrimidine Thieno[2,3-b]pyridine Antimicrobial

Performance of the Aluminide Coating of SomeLow Alloy Steels

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Journal of Materials Science & Technology 1997年第6期13卷 462-466页

作者： H.M.Soliman and M.e.Abd e1-Azim(Metallurgy Dept., Atomic energy Authority, Cairo, egypt ) Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Two low alloy steels 0.5Cr-0.5Mo-0.25V and H85 were pack-aluminized at 900°for 4 h by using Fe-Al powder mixture containing 48% Fe, 20.6% Al- 29.4% Al2O3 and 2% NH4Cl by weight. The microhardness and oxidation resistance at 900℃ of the aluminide coatings were studied. It was found that pack-aluminizing improves the microhardness of the 0.5Cro.5Mo-0.25V steel while it reduces the microhardness of the H85 steel. Pack aluminizing highly improves the oxidation resistance after 20h exposure at 900℃ in air for the investigated steels.

关键词： Cr Performance of the Aluminide Coating of SomeLow Alloy Steels

The anti-correlation method for removing harmonic distortion in vibroseis slip-sweep data

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Applied Geophysics 2012年第2期9卷 159-167,234页

作者：张红静周辉 Abd e1-Aziz khairy Abd e1-Aal 张洁油气资源与探测国家重点实验室 CNPC物探重点实验室中国石油大学(北京) National Research Institute of Astronomy and Geophysics(NRIAG) Department of SeismologyHelwan11722 CairoEgypt 中国石化石油物探技术研究院

The slip-sweep technique is one of the high-efficiency, high-fidelity, and environmental vibroseis seismic prospecting techniques which consists of a vibrator group sweeping without waiting for the previous group＇s sweep to terminate. The cycle time can be reduced drastically and hence the production efficiency can be increased significantly but harmonic distortion of one sweep will leak into the record of the other sweep. In this paper, we propose an anti-correlation method for removing harmonic distortion in vibroseis data. This method is based on decomposition of the ground force signal into fundamental and harmonic components. Then the corresponding anti-correlation operator can be computed to estimate the energy of each harmonic after correlating the vibroseis data with the corresponding harmonic component. Finally, the vibroseis harmonic noise to be removed can be obtained by subtracting the extracted harmonic noise from the traces of the previous group＇s sweep. The advantage of the proposed method is that it can process both uncorrelated and correlated vibroseis seismic data. Moreover, the algorithm is simple, stable, and computationally fast. especially, the significant contribution of this method is a considerable reduction in the harmonic without any alteration of the desired signals. The method was tested on both synthetic and field data sets to validate the good harmonic noise suppression results.

关键词： vibroseis slip-sweep acquisition anti-correlation method harmonic distortion removal