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Nonlinear description of Yang-Mills cosmology： cosmic inflation and the accompanying Hannay's angle

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Chinese Physics C 2017年第6期41卷 115-121页

作者： Yacine Bouguerra mustapha maamache Jeong Ryeol Choi Laboratoire de Physique Quantique et Systèmes Dynamiques Faculté des SciencesUniversite Ferhat Abbas Setif 1 Setif 19000 Algeria Département de Physique Facultédes Sciences Université de Jijel BP 98Ouled Aissa Jijel 18000 Algeria Department of Radiologic Technology Daegu Health College Yeongsong-ro 15 Buk-gu Daegu 41453 Republic of Korea

Hannay＇s angle is a classical analogue of the ＂geometrical phase factor＂ found by Berry in his research on the quantum adiabatic theorem. This classical analogue is defined if closed curves of constant action variables return to the same curves in phase space after an adaibatic evolution. Adiabatic evolution of Yang-Mills cosmology, which is described by a time-dependent quartic oscillator, is investigated. Phase properties of the Yang-Mills fields are analyzed and the corresponding Hannay＇s angle is derived from a rigorous evaluation. The obtained Hannay＇s angle shift is represented in terms of several observable parameters associated with such an angle shift. The time evolution of Hannay＇s angle in Yang-Mills cosmology is examined from an illustration plotted on the basis of numerical evaluation,and its physical nature is addressed. Hannay＇s angle, together with its quantum counterpart Berry＇s phase, plays a pivotal role in conceptual understanding of several cosmological problems and indeed can be used as a supplementary probe for cosmic inflation.

关键词： Yang-Mills cosmology Hannay angle time-dependent quartic Hamiltnian inflation

Mechanical and Metallurgical Characterization of HSLA X70Welded Pipeline Steel Subjected to Successive Repairs

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Acta Metallurgica Sinica(English Letters) 2016年第6期29卷 568-576页

作者： Bouzid maamache Mabrouk Bouabdallah Abdelhalim Brahimi Youcef Yahmi Billel Cheniti Brahim Mehdi Research Center in Industrial Technologies(CRTI) P.O.Box 6416014 CheragaAlgeria Laboratoire des Aeronefs Universite de Blidal09000 BlidaAlgeria LGSDS Ecole Nationale PolytechniqueEl Harrach16200AlgiersAlgeria LTSM Universite de Blidal09000 BlidaAlgeria ICMMO/SP2M Bat 410Universite Paris-Sud 1191405Orsay CedexFrance

The aim of this work is to study the influence of successive weld repairs on the microstructure and the mechanical behavior of the heat-affected zone（HAZ） of an HSLA X70 steel. Detailed microstructural examination combined to grain size measurement showed that beyond the second weld repair, the microstructure of the HAZ undergoes significant change in the grain morphology and grain growth. The results of the X-ray diffraction analyzed using MAUD software indicated an increase in the crystallite size and a decrease in the dislocation density according to the number of weld repair operations. Consequently, a loss of mechanical properties, namely the yield strength and the toughness with the number of weld repairs, was recorded. Beyond the second weld repair operation, the properties of the welded joint do not fulfill the standards applied in piping industry.

关键词： HSLA X70 steel Successive weld repair Heat affected zone Dislocation density

Generalized Coherent States of a Particle in a Time-Dependent Linear Potential

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Chinese Physics Letters 2009年第7期26卷 36-39页

作者： L. Krache M. maamache Y. Saadi A. Beniaiche Lab PQSD Faculté des Sciences Université Ferhat Abbas de Sétif Sétif 19000 Algeria Lab SPONL Faculté des Sciences de l'Ingénieur Université Ferhat Abbas de Sétif Sétif 19000 Algeria

We derive, with an invariant operator method and unitary transformation approach, that the Schr6dinger equation with a time-dependent linear potential possesses an infinite string of shape-preseving wave-packet states 1φ,λ （t） having classical motion. The qualitative properties of the invariant eigenvalue spectrum （discrete or continuous） are described separately for the different values of the frequency ω of a harmonic oscillator. It is also shown that, for a discrete eigenvalue spectrum, the states 1φ,λ （t） could be obtained from the coherent state 1φ,λ （t）.

关键词： Mathematical physics Quantum information and quantum mechanics

Influence of Auxiliary Equation on Wave Functions for Time-Dependent Pauli Equation in Presence of Aharonov-Bohm Effect

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Communications in Theoretical Physics 2009年第5期51卷 803-810页

作者： M.maamache C.Lahoulou Y.Saadi Laboratoire

Invariant operator method for discrete or continuous spectrum eigenvalue and unitary transformation approach are employed to study the two-dimensional time-dependent Pauli equation in presence of the Aharonov-Bohm effect （AB） and external scalar potential. For the spin particles the problem with the magnetic field is that it introduces a singularity into wave equation at the origin. A physical motivation is to replace the zero radius flux tube by one of radius R, with the additional condition that the magnetic field be confined to the surface of the tube, and then taking the limit R → 0 at the end of the computations. We point that the invariant operator must contain the step function θ（r - R）. Consequently, the problem becomes more complicated. In order to avoid this dimculty, we replace the radius R by ρ（t）R, where ρ（t） is a positive time-dependent function. Then at the end of calculations we take the limit R →0. The qualitative properties for the invariant operator spectrum are described separately for the different values of the parameter C appearing in the nonlinear auxiliary equation satisfied by p（t）, i.e., C 〉 0, C = 0, and C 〈0. Following the C＇s values the spectrum of quantum states is discrete （C 〉 0） or continuous （C ≤ 0）.

关键词： time-dependent systems invariant theory Aharonov-Bohm effect Pauli equation

A new experimental way for the monitoring of the real/equivalent inservice- time of double base rocket propellant by coupling VST and PCA

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Defence Technology（防务技术） 2021年第2期17卷 440-449页

作者： Salim Chelouche Djalal Trache Ilyas maamache Ahmed Fouzi Tarchoun Kamel Khimeche Abderrahmane Mezroua UER Procedes Energetiques Ecole Militaire PolytechniqueEMPBP 17 Bordj-El-Bahri16046AlgiersAlgeria

The assessment of the real in-service-time(RIST)and the equivalent in-service-time(EIST)of double base rocket propellants(DBRPs)is of utmost importance for the safe storage and use of weapon systems as well as the efficiency of the accelerated aging *** this work,four DBRPs with similar chemical composition and different natural aging have been artificially aged at T?338.65 K for 4 months with sampling every 30 *** unaged and artificially aged samples have been investigated by vacuum stability test(VST)at five isothermal temperatures(T?333.15 K,343.15 K,353.15 K,363.15 K,and 373.15 K).The volume of the evolved gases in VST was found to decrease with natural/artificial ***,the VST data were treated and subjected to principal component analysis(PCA).The results showed excellent discrimination of the DBRP samples according to their stability thermal *** of the variance was described by the first principal component(PC1)whose scores were linearly correlated with the natural aging durations when PCA is applied on VST data obtained at T?363.15 *** light of the obtained results,a new experimental way for the estimation of the real/equivalent IST was proposed,which takes into account the impact of the natural aging of the *** approach predicts successfully the RIST of two similar DBRPs with a relative deviation of less than 2%.At the specific heating temperature T?338.65 K,the developed model provides more conceivable EIST values,with asymptotic behavior against artificial aging duration evolution,thus overcoming some shortcomings of the common generalized van’t Hoff formula(GvH).

关键词： Chemometrics van’t hoff rule Natural aging Artificial aging Stability Storage

Development,Capitalism Transformation and Marxism

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学术界 2019年第2期 185-192页

作者： mustapha Machrafi Faculty of Law Economics and Social Science Mohammed V University

Development,Capitalism Transformation and

关键词： capitalism Marxism sub-Saharan Africa political economy paradigm shift

Substructure design optimization and nonlinear responses control analysis of the mega-sub controlled structural system (MSCSS) under earthquake action

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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 687-704页

作者： mustapha Abdulhadi Zhang Xun′an Buqiao Fan Muhammad Moman College of Mechanics and Civil Engineering Northwestern Polytechnic UniversityXi’an 710071China

The newly proposed mega sub-controlled structure system(MSCSS)and related studies have drawn the attention of civil engineers for practice in improving the performance and enhancing the structural effectiveness of mega frame ***,there is still a need for improvement to its basic structural *** this project,an advanced,reasonable arrangement of mega sub-controlled structure models,composed of three mega stories with different numbers and arrangements of substructures,are designed to investigate the control performance of the models and obtain the optimal model configuration(model with minimum acceleration and displacement responses)under strong earthquake *** addition,the dynamic parameters that affect the performance effectiveness of the optimal model of MSCSS are studied and *** area of the relative stiffness ratio RD,with different mass ratio MR,within which the acceleration and displacement of the optimal model of MSCSS reaches its optimum(minimum)value is considered as an optimum *** serves as a useful tool in practical engineering *** study demonstrates that the proposed MSCSS configuration can efficiently control the displacement and acceleration of high rise *** addition,some analytical guidelines are provided for selecting the control parameters of the structure.

关键词： mega sub-controlled structure system(MSCSS) optimal model viscous damper dynamic parameters control effectiveness response control rubber bearing

Gyroscope precession frequency analysis of a five-dimensional charged rotating Kaluza-Klein black hole

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Chinese Physics C 2020年第6期44卷 143-153页

作者： mustapha Azreg-Aïnou Mubasher Jamil Kai Lin Engineering Faculty Başkent UniversityBağlıca CampusAnkaraTurkey Institute for Theoretical Physics and Cosmology Zhejiang University of TechnologyHangzhou 310023China School of Natural Sciences National University of Sciences and TechnologyH-12Islamabad 44000Pakistan Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China

We study the spin precession frequency of a test gyroscope attached to a stationary observer in the five-dimensional rotating Kaluza-Klein black hole(RKKBH). We derive the conditions under which the test gyroscope moves along a timelike trajectory in this geometry, and the regions where the spin precession frequency diverges. The magnitude of the gyroscope precession frequency around the KK black hole diverges at two spatial locations outside the event horizon. However, in the static case, the behavior of the Lense-Thirring frequency of a gyroscope around the KK black hole is similar to the ordinary Schwarzschild black hole. Since a rotating Kaluza-Klein black hole is a generalization of the Kerr-Newman black hole, we present two mass-independent schemes to distinguish these two spacetimes.

关键词： rotating black hole Kaluza-Klein spin precession gyroscope

South Carolina forestland owners’ willingness to accept compensations for carbon sequestration

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Forest Ecosystems 2019年第2期6卷 119-131页

作者： mustapha Alhassan Marzieh Motallebi Bo Song Clemson University Baruch Institute of Coastal Ecology and Forest Science P. O. Box 596 Georgetown SC 29442 USA U.S. Geological Survey Science and Decisions Center 12201 Sunrise Valley Drive Mail Stop 913 Reston VA 20192 USA

Background: Carbon sequestration through recommended forest management practices is an ecosystem service that helps mitigate climate change and its impacts while generating carbon credits for forestland owners to sell in cap-and-trade programs. The California’s cap-and-trade program (California’s carbon market hereafter) allows forestland owners from any part of the contiguous United States to supply carbon credits to compliance entities. In this study, we estimate South Carolina (SC) private forestland owners’willingness to accept compensations to participate in the California’s carbon market using a contingent valuation method. Results: We estimate forestland owners’mean willingness to accept as$67 per acre per year. Our results reveal higher probability of participation of forestland owners with interests in preserving forest ecosystems than those who do not. Additionally, forestland owners who trust in information about climate change from scientists or government are willing to participate more than those who do not. Conclusions: Various factors hinder landowners’ability to participate in carbon markets. Forestland owners in SC consider legislative uncertainty and long-time commitment as the main barriers to participation in California’s carbon market. From this research, average forestland tenure in SC is 27 years, which is far less than the 100-year time commitment of the California’s carbon market. Of those who agreed to participate, choosing between adopting and not adopting any of the three main forest management practices in the California’s carbon market:28% are likely to adopt improved forest management (IFM) practices, 24% are likely to adopt reforestation due to understocked forestlands, and 14% are likely to adopt avoided conversion. In another development, the concept of aggregation has dominated discussions in the California’s carbon market of late. It is an advocacy to include small-scale forestlands in the California’s carbon market. To aggregate

关键词： Forestland owners Carbon markets Willingness to accept