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冯·卡门后期的工作和他留下的遗产

力学进展 2010年第1期40卷 99-109页

作者： s s Penner F A Williams P A Libby s nemat-nasser 陶彩军加利福尼亚大学机械航空工程系中国科学院力学研究所

在早期出版的有关西奥多·冯·卡门的传记中,sears和sears(1979年)写到了他在德国哥廷根(1908年～1912年)、亚琛(1912年～1930年)以及他于1930年～1952年间在加州理工学院古根海姆航空实验室工作的情况.因此,本文只讨论他后期(即从1952... 详细信息

在早期出版的有关西奥多·冯·卡门的传记中,sears和sears(1979年)写到了他在德国哥廷根(1908年～1912年)、亚琛(1912年～1930年)以及他于1930年～1952年间在加州理工学院古根海姆航空实验室工作的情况.因此,本文只讨论他后期(即从1952年～1963年他逝世这一时期)的工作情况,也评述他的科学遗产,并确认继承冯.卡门风格从事气动热化学和相关领域研究的代表性研究机构和杰出研究人员.

关键词：气动热化学航空研究与发展咨询组国际宇宙航行学会

synergistic effects of the entomopathogenic fungus Isaria javanica and low doses of dinotefuran on the efficient control of the rice pest sogatella furcifera

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Journal of Integrative Agriculture 2024年第2期23卷 621-638页

作者： Tingting Zhou Qian Zhao Chengzhou Li Lu Ye Yanfang Li nemat OKeyhani Zhen Huang Department of Entomology College of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Key Laboratory of High Technology for Plant Protection Plant Protection Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510642China Department of Microbiology and Cell science Institute of Food and Agricultural SciencesUniversity of FloridaFL 32611USA

The rice planthopper,sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza *** is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical *** investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on *** under both laboratory and field *** results show that *** displays high infection efficiency and mortality for different stages of ***,reducing adult survival,female oviposition and ovary *** bioassays showed that the combined use of *** with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in *** than the use of *** or dinotefuran *** combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase *** field trials,*** effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of *** populations using the combination of a low dose of ***(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days *** findings indicate that the entomogenous fungus *** offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.

关键词： Isaria javanica sogatella furcifera entomopathogenic fungus white planthopper rice synergistic effect on pest control

Laser beam effect on the entanglement of elastic collisions in quantum plasma

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Communications in Theoretical Physics 2024年第8期76卷 147-155页

作者： Ramin Roozehdar Mogaddam nasser sepehri Javan Hosein Mohammadzadeh Department of Physics Ferdowsi University of MashhadPO Box 1436MashhadIran Department of Physics University of Mohaghegh ArdabiliPO Box 179ArdabilIran

In the quantized field formalism, using Kramers-Henneberger unitary transformation as the semi-classical counterpart of Block-Nordsieck transformation, the dynamics of entanglement during the low energy scattering processes in bi-partite systems at the presence of a laser beam fields are studied. The stationary-state schrodinger equation for the quantum scattering process is obtained for such systems. Then, using partial wave analysis, we introduce a new form of entanglement fidelity considering the effect of high-intensity laser beam fields. The effective potential of hot quantum plasma including plasmon and quantum screening effects is used to obtain the entanglement fidelity ratio as a function of the laser amplitude, and plasmon and Debye length parameters for the elastic electron-ion collisions. It is shown that the plasma free electrons oscillations under interaction with laser beam fields improve the correlations between charged particles and consequently lead to the increase in the system entanglement.

关键词： laser entanglement quantum plasma elastic collision plasmon fidelity

Evaluation of urea breath test as a diagnostic tool for Helicobacter pylori infection in adult dyspeptic patients

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World Journal of Gastroenterology 2024年第17期30卷 2302-2307页

作者： Zeinab Nabil Ahmed said Asmaa Mohamed El-nasser Department of Medical Microbiology&Immunology Faculty of Medicine for Girls Al-Azhar UniversityNasr City 11754CairoEgypt

In this editorial,we discuss the article in the World Journal of *** article conducts a meta-analysis of the diagnostic accuracy of the urea breath test(UBT),a non-invasive method for detecting Helicobacter pylori(***)infection in *** is based on radionuclide-labeled *** methods,both invasive and non-invasive,are available for diagnosing *** infection,inclu-ding endoscopy with biopsy,serology for immunoglobulin titers,stool antigen analysis,and *** guidelines recommend UBTs as the primary choice for diagnosing *** infection and for reexamining after eradication *** is used to be the first choice non-invasive test due to their high accuracy,specificity,rapid results,and ***,its performance remains unaffected by the distribution of *** in the stomach,allowing a high flow of patients to be *** its widespread use,the performance characteristics of UBT have been inconsistently described and remain incompletely *** are two UBTs available with Food and Drug Administration approval:The 13C and 14C *** tests are affordable and can provide real-time *** may prefer the 13C test because it is non-radioactive,compared to 14C which uses a radioactive isotope,especially in young children and pregnant *** there was heterogeneity among the studies regarding the diagnostic accuracy of both UBTs,13C-UBT consistently outperforms the *** makes the 13C-UBT the preferred diagnostic ***,the provided findings of the meta-analysis emphasize the significance of precise considerations when choosing urea dosage,assessment timing,and measurement techniques for both the 13C-UBT and 14C-UBT,to enhance diagnostic precision.

关键词： Helicobacter pylori Urea breath test Diagnosis Diagnostic test accuracy Meta-analysis

Numerical Treatments for Crossover Cancer Model of Hybrid Variable-Order Fractional Derivatives

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Computer Modeling in Engineering & sciences 2024年第8期140卷 1619-1645页

作者： nasser sweilam seham Al-Mekhlafi Aya Ahmed Ahoud Alsheri Emad Abo-Eldahab Mathematics Department Faculty of ScienceCairo UniversityGiza12613Egypt Mathematics Department Faculty of EducationSana’a UniversitySana’a1247Yemen Mathematics Department Faculty of ScienceHelwan UniversityCairo11795Egypt Department of Mathematics College of ScienceUniversity of BishaAl Namas67398-5644Saudi Arabia

In this paper,two crossover hybrid variable-order derivatives of the cancer model are ***ünwald-Letnikov approximation is used to approximate the hybrid fractional and variable-order fractional *** existence,uniqueness,and stability of the proposed model are *** Bashfourth’s fifth-step method with a hybrid variable-order fractional operator is developed to study the proposed *** studies with generalized fifth-order Runge-Kutta method are *** examples and comparative studies to verify the applicability of the used methods and to demonstrate the simplicity of these approximations are *** have showcased the efficiency of the proposed method and garnered robust empirical support for our theoretical findings.

关键词： Cancer diseases hybrid variable-order fractional derivatives adams bashfourth fifth step generalized fifth order Runge-Kutta method

A Hybrid Classification and Identification of Pneumonia Using African Buffalo Optimization and CNN from Chest X-Ray Images

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Computer Modeling in Engineering & sciences 2024年第3期138卷 2497-2517页

作者： nasser Alalwan Ahmed I.Taloba Amr Abozeid Ahmed Ibrahim Alzahrani Ali H.Al-Bayatti Computer science Department Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Information system Department Faculty of Computers and InformationAssiut UniversityAssiutEgypt Mathematics Department Faculty of ScienceAl-Azhar UniversityCairoEgypt Cyber Technology Institute(CTI) De Montfort UniversityLeicesterUK

An illness known as pneumonia causes inflammation in the *** there is so much information available fromvarious X-ray images,diagnosing pneumonia has typically proven *** improve image quality and speed up the diagnosis of pneumonia,numerous approaches have been *** date,several methods have been employed to identify *** Convolutional Neural Network(CNN)has achieved outstanding success in identifying and diagnosing diseases in the fields of medicine and ***,these methods are complex,inefficient,and imprecise to analyze a big number of *** this paper,a new hybrid method for the automatic classification and identification of Pneumonia from chest X-ray images is *** proposed method(ABOCNN)utilized theAfrican BuffaloOptimization(ABO)algorithmto enhanceCNNperformance and *** Weinmed filter is employed for pre-processing to eliminate unwanted noises from chest X-ray images,followed by feature extraction using the Grey Level Co-Occurrence Matrix(GLCM)*** features are then selected from the dataset using the ABO algorithm,and ultimately,high-performance deep learning using the CNN approach is introduced for the classification and identification of *** results on various datasets showed that,when contrasted to other approaches,the ABO-CNN outperforms them all for the classification *** proposed method exhibits superior values like 96.95%,88%,86%,and 86%for accuracy,precision,recall,and F1-score,respectively.

关键词： African buffalo optimization convolutional neural network pneumonia X-ray

Refraction characteristics of phononic crystals

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Acta Mechanica sinica 2015年第4期31卷 481-493页

作者： sia nemat-nasser Department of Mechanical and Aerospace Engineering University of California

some of the most interesting refraction prop- erties of phononic crystals are revealed by examining the anti-plane shear waves in doubly periodic elastic composites with unit cells containing rectangular and/or elliptical multi- inclusions. The corresponding band structure, group velocity, and energy-flux vector are calculated using a powerful mixed variational method that accurately and efficiently yields all the field quantities over multiple frequency pass-bands. The background matrix and the inclusions can be anisotropic, each having distinct elastic moduli and mass densities. Equifrequency contours and energy-flux vectors are read- ily calculated as functions of the wave-vector components. By superimposing the energy-flux vectors on equifrequency contours in the plane of the wave-vector components, and supplementing this with a three-dimensional graph of the corresponding frequency surface, a wealth of information is extracted essentially at a glance. This way it is shown that a composite with even a simple square unit cell con- taining a central circular inclusion can display negative or positive energy and phase velocity refractions, or simply performs a harmonic vibration （standing wave）, depending on the frequency and the wave-vector. Moreover, that the same composite when interfaced with a suitable homoge- neous solid can display：（1） negative refraction with negative phase velocity refraction; （2） negative refraction with pos- itive phase velocity refraction; （3） positive refraction with negative phase velocity refraction; （4） positive refraction with positive phase velocity refraction; or even （5） completereflection with no energy transmission, depending on the fre- quency, and direction and the wavelength of the plane-wave that is incident from the homogeneous solid to the interface. For elliptical and rectangular inclusion geometries, analyti- cal expressions are given for the key calculation quantities. Expressions for displacement, velocity, linear m

关键词： Doubly periodic composites - Phononiccrystals Band structure Group and energy-flux vectors

Energy exchange between charged relativistic fluids in f(T) gravity

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Communications in Theoretical Physics 2024年第10期 108-120页

作者： Z Yousaf U A Khokhar nasser Bin Turki T suzuki Department of Mathematics University of the Punjab Quaid-i-Azam Campus Department of Mathematics College of Science King Saud University Department of Regional Management Faculty of Management Fukushima College

This study focuses on the effects of a polytropic fluid on a charged gravitational source within f(T) gravity, where T is the torsion scalar. We investigate how the electromagnetic field affects the flow of energy in spherically symmetric and static celestial objects that contain relativistic fluids. By using the gravitational decoupling technique, we analyze the effects of polytropic fluid on the dynamics of the gravitational source, accompanied by the matching of the interior geometry with an exterior at the hypersurface Σ. Finally, with the help of the Tolman ⅡV solution, we observe the conduct of energy conditions with the existence of charge using f(T)field equations and got the intended outcomes.

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Dynamics of Non-Markovianity, Quantum Correlations and Information scrambling of Three Qubits systems Interacting via Rashba Interaction

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Journal of Quantum Information science 2024年第2期14卷 52-67页

作者： nasser Metwally Fawzeya Ebrahim Department of Mathematics College of Science University of Bahrain Zallaq Bahrain Department of Mathematics Aswan University Aswan Egypt

The behavior of the quantum correlations, information scrambling and the non-Markovianity of three entangling qubits systems via Rashba is discussed. The results showed that, the three physical quantities oscillate between their upper and lower bounds, where the number of oscillations increases as the Rashba interaction strength increases. The exchanging rate of these three quantities depends on the Rashba strength, and whether the entangled state is generated via direct/indirect interaction. Moreover, the coherence parameter can be used as a control parameter to maximize or minimize the three physical quantities.

关键词： Markovianity Correlations Rashba Interaction scrambling Information