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Hyper Heuristic Approach for Design and Optimization of Satellite Launch Vehicle

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Chinese Journal of Aeronautics 2011年第2期24卷 150-163页

作者： amer Farhan RAFIQUE HE Linshu Ali KamRAN Qasim ZEESHAN Department of Spacecraft Technology School of Astronautics Beihang University Beijing 100191 China Department of Space Propulsion School of Astronautics Beihang University Beijing 100191 China

Satellite launch vehicle lies at the cross-road of multiple challenging technologies and its design and optimization present a typical example of multidisciplinary design and optimization（MDO） *** complexity of problem demands highly effi-cient and effective algorithm that can optimize the *** heuristic approach（HHA） based on meta-heuristics is applied to the optimization of air launched satellite launch vehicle（ASLV）.A non-learning random function（NLRF） is proposed to con-trol low-level meta-heuristics（LLMHs） that increases certainty of global solution,an essential ingredient required in product conceptual design phase of aerospace *** empirical study is performed to evaluate the performance advan-tages of proposed approach over popular non-gradient based optimization *** of ASLV encompasses aerodynamics,propulsion,structure,stages layout,mass distribution,and trajectory modules connected by multidisciplinary feasible design *** approach formulates explicit system-level goals and then forwards the design optimization process entirely over to *** distinctive approach for launch vehicle system design relieves engineers from tedious,iterative task and en-ables them to improve their component level *** is an impetus on vehicle performance and cost,and so it is considered as the core of vehicle design ***,gross launch mass is to be minimized in HHA.

关键词： multidisciplinary design optimization satellite launch vehicle heuristic optimization methods hyper heuristic air launched vehicles

Duffing Oscillator’s Vibration Control under Resonance with a Negative Velocity Feedback Control and Time Delay

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Sound & Vibration 2021年第3期55卷 191-201页

作者： Y.A.amer Taher A.Bahnasy Department of Mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Department of Engineering Physics and Mathematics Faculty of EngineeringTanta UniversityTantaEgypt

An externally excited Duffing oscillator under feedback control is discussed and analyzed under the worst resonance *** time scales method is applied for this system to find analytic solution with the existence and nonexistence of the time delay on control *** appropriate stability analysis is also performed and appropriate choices for the feedback gains and the time delay are found in order to reduce the amplitude *** response curves are involved to show and compare controller *** addition,analytic solutions are compared with numerical approximation solutions using Rung-Kutta method of fourth order.

关键词： Non-linear dynamical system multiple time scales method active feedback controller time delay

Production and evaluation of novel functional extruded corn snacks fortified with ginger,bay leaves and turmeric powder

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Food Production, Processing and Nutrition 2022年第1期4卷 41-57页

作者： Sara Adel amer Ayat Ebrahim Rizk Special Food and Nutrition Research Department Food Technology Research Institute.Agricultural Research Center9 Gamaa StreetGizaEgypt

Extruded corn snacks are accepted by all human ages especially children, but they have low functional value. Therefore, corn extruded snacks contain rich nutraceuticals dried herbs including Laurus nobilis (T1), Curcuma longa (T2), Zingiber officinale Roscoe (T3), and the mixture of these herbs (T4) were manufactured and analyzed. The results declared that all the herbal extruded corn snacks had significantly higher ash, fibers, minerals, and vitamins A and B6. For minerals, the highest percent of increase compared to control was achieved by Fe, K, Ca, Zn content in order, being the highest in T4. The contents of Vitamin A and B6 were ranged from 283 to 445 IU/100 g and from 0.01 to 0.08 mg/100 g for the herbal extrudates, respectively. The increased percent in herbal corn snacks relative to control ranged from 743 to 452%, 188 to 17.6%, and from 313 to 99% for total phenolics, flavonoids, and antioxidant activity. Besides, the highest number of phenolic compounds was recorded in T4. Despite the fact that approximately all herbal extruded products had good texture and color characteristics, the best formulation was T2 and T4 corn snacks. Furthermore, the extruded products were microbiologically safe for up to 9 months. The formulation of herbal-corn snacks could fulfill consumers’ requirement for ready-to-eat-healthy foods with acceptable sensory attributes and also economically suitable for the food industry.

关键词： Ginger Laurel Turmeric Extrusion Corn snacks functional foods

Heat transfer and airflow characteristics enhancement of compact plate-pin fins heat sinks–a review

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Propulsion and Power Research 2018年第2期7卷 138-146页

作者： amer Al-damook Fahad Saleh Alkasmoul Mechanical Engineering Department Faculty of EngineeringUniversity of AnbarIraq King Abdulaziz City for Science and Technology in Riyadh Saudi Arabia

Plate-pin heat sinks are widely used for the electronic cooling system,internal combustion IC engine,cooling of gas turbine blades and other different applications to enhance the thermal performance of heat sinks due to simplicity,low cost,and a reliable manufacturing ***,compact heat sinks give higher pressure drop compared with other types of heat *** purpose of this article is to summarise the main advantages and disadvantages of the compact heat sink with some recommendation studies for future works heat sink thermal airflow experiment and ***,the research attempts to highlight the importance of balance the relationship between the hydraulic performance and the thermal performance of compact heat sinks。

关键词： Heat sinks Heat transfer enhancement for applications Conjugate heat transfe

Mathematical modeling of female breast cancer in Japan

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International Journal of Biomathematics 2020年第4期13卷 33-47页

作者： Ahmed Nagah Asmaa amer Xinan Zhang School of Mathematics and Statistics Central China Normal UniversityWuhan 430079P.R.China Mathematics Department Faculty of Science Zagazig UniversityZagazigEgypt Mathematics Department Faculty of Science Menoufia UniversityEgypt

Cancer incidence rates are significantly diferent all over the *** cancer is affected by many factors,the most important being genetics and *** aim of this paper is to study the mutation mechanisms of breast cancer for Japanese women by fitting the incidence data of three high-quality population areas in Japan from 1985 to *** achieve this goal,we have set up multi-stage models within the mathematical model of Moolgavkar,Venzon,and *** models take both mutation rates and clonal expansion rates as parameters in each compartment into *** on our simulation outcomes,two to twelve driver mutations are sufficient in the pathway to female breast cancer in *** the other hand,a previous study demonstrated that breast cancer in american women requires two to fourteen gene mutations to get a cancerous ***,the 3-stage mat hematical model is the optimal model as it fits clinical data very nicely for all affected cases of females in Japan and the *** genetic instability has a promincnt effect on the tumorigenesis of Japanese females caused by the first four driver *** calculated results for Japanese women are compared with previous works for american women.

关键词： Breast cancer multi-stage models genetic instability chi-square test

Inverse Length Biased Maxwell Distribution:Statistical Inference with an Application

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Computer Systems Science & Engineering 2021年第10期39卷 147-164页

作者： amer Ibrahim Al-Omari Ayed R.A.Alanzi Department of Mathematics Faculty of ScienceAl al-Bayt UniversityMafraqJordan Department of Mathematics College of Science and Human Studies at Hotat SudairMajmaah UniversityMajmaah 11952Saudi Arabia

In this paper,we suggested and studied the inverse length biased Maxell distribution(ILBMD)as a new continuous distribution of one *** ILBMD is obtained by considering the inverse transformation technique of the Maxwell length biased *** characteristics of the ILBMD such as the moments,moment generating function,mode,quantile function,the coefficient of variation,coefficient of skewness,Moors and Bowley measures of kurtosis and skewness,stochastic ordering,stress-strength reliability,and mean deviations are *** addition,the Bonferroni and Lorenz curves,Gini index,the reliability function,the hazard rate function,the reverse hazard rate function,the odds function,and the distributions of order statistics for the ILBMD,are *** ILBMD parameter is estimated using the maximum likelihood method,the method of moments,the maximum product of spacing technique,the ordinary and weight least square procedures,and the Cramer-Von-Mises *** Fishers information,as well as the Rényi and q-entropies,are *** investigate the usefulness of the proposed lifetime distribution and to illustrate the purpose of the study,a real dataset of the relief times of 20 patients receiving an analgesic is used.

关键词： Maxell distribution inverse length biased Maxwell distribution Fisher’s information methods of estimation goodness of fit tests

Electromagnetic Time Reversal Algorithms and Source Localization in Lossy Dielectric Media

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Communications in Theoretical Physics 2014年第12期61卷 779-789页

作者： Abdul Wahab amer Rasheed Tasawar Hayat Rab Nawaz Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAam) Research Group Faculty of Science King Abdulaziz University

The problem of reconstructing the spatial support of an extended radiating electric current source density in a lossy dielectric medium from transient boundary measurements of the electric fields is studied. A time reversal algorithm is proposed to localize a source density from loss-less wave-field measurements. Further, in order to recover source densities in a lossy medium, we first build attenuation operators thereby relating loss-less waves with lossy ones. Then based on asymptotic expansions of attenuation operators with respect to attenuation parameter, we propose two time reversal strategies for localization. The losses in electromagnetic wave propagation are incorporated using the Debye's complex permittivity, which is well-adopted for low frequencies(radio and microwave) associated with polarization in dielectrics.

关键词： time reversal electromagnetic waves inverse source problem Debye’s law attenuation operators

New Improved Ranked Set Sampling Designs with an Application to Real Data

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Computers, Materials & Continua 2021年第5期67卷 1503-1522页

作者： amer Ibrahim Al-Omari Ibrahim M.Almanjahie Department of Mathematics Faculty of ScienceAl al-Bayt UniversityMafraqJordan Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia

This article proposes two new Ranked Set Sampling(RSS)designs for estimating the population parameters:Simple Z Ranked Set Sampling(SZRSS)and Generalized Z Ranked Set Sampling(GZRSS).These designs provide unbiased estimators for the mean of symmetric *** is shown that for non-uniform symmetric distributions,the estimators of the mean under the suggested designs are more efcient than those obtained by RSS,Simple Random Sampling(SRS),extreme RSS and truncation based RSS ***,the proposed RSS schemes outperform other RSS schemes and provide more efcient estimates than their competitors under imperfect *** suggested mean estimators under perfect and imperfect rankings are more efcient than the linear regression estimator under *** proposed RSS designs are also extended to cover the estimation of the population *** data is used to examine wthe usefulness and efciency of our estimators.

关键词： Ranked set sampling unbiased estimator simple random sampling mean squared error efciency imperfect ranking

Active control of an aircraft tail subject to harmonic excitation

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Acta Mechanica Sinica 2007年第4期23卷 451-462页

作者： M.Eissa H.S.Bauomy Y.A.amer Department of Engineering Mathematics Faculty of Electronic EngineeringMenouf 32952Egypt Department of Mathematics Faculty of ScienceZagazig UniversityZagazigEgypt

Vibration of structures is often an undesirable phenomena and should be avoided or controlled. There are two techniques to control the vibration of a system, that is, active and passive control techniques. In this paper, a negative feedback velocity is applied to a dynamical system, which is represented by two coupled second order nonlinear differential equations having both quadratic and cubic nonlinearties. The system describes the vibration of an aircraft tail. The system is subjected to multi-external excitation forces. The method of multiple time scale perturbation is applied to solve the nonlinear differential equations and obtain approximate solutions up to third order of accuracy. The stability of the system is investigated applying frequency response equations. The effects of the different parameters are studied numerically. Various resonance cases are investigated. A comparison is made with the available published work.

关键词： Active vibration control Stability Response curves Aircraft tail