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One-Dimensional symmetry and Liouville Type Results for the Fourth Order Allen-Cahn Equation in R^N

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Chinese Annals of Mathematics,series B 2017年第1期38卷 149-172页

作者： denis BONHEURE Franois HAMEL Département de Mathématique Université libre de Bruxelles INRIA-Team MEPHYsTO Aix Marseille Univ CNRSCentrale Marseille

In this paper, the authors prove an analogue of Gibbons' conjecture for the extended fourth order Allen-Cahn equation in R^N, as well as Liouville type results for some solutions converging to the same value at infinity in a given direction. The authors also prove a priori bounds and further one-dimensional symmetry and rigidity results for semilinear fourth order elliptic equations with more general nonlinearities.

关键词： Fourth order elliptic equation Allen-Cahn equation Extended Fisher-Kolmogorov equation One-dimensional symmetry Liouville type results

Polarization in cyclotron radiation in strong magnetic fields

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Research in Astronomy and Astrophysics 2010年第10期10卷 1023-1040页

作者： Luidmila semionova denis Leahy Jorge Paez Department of Physics Universidad National Department of Physics and Astronomy University of CalgaryA space Research Center University of Costa Rica

We revisit the problem of radiative transitions of electrons in the presence of a strong magnetic field. We derive fully relativistic cyclotron transition rates for an arbitrary magnetic field, for any orientation of electron spin and for any polarization of the emitted radiation. Also, we obtain the transition rates for any value of the initial electron＇s parallel momentum. For very strong magnetic fields, transitions to the ground state predominate. Transition rates summed over the electron＇s spin orientation and for unpolarized radiation are also obtained, which confirm previous results by Latal. Transition widths are calculated for different electron spin orientations and different polarizations of radiation. We obtain general expressions for transition rates that reduce to the results for the non-relativistic case and for unpolarized radiation. Additionally we get, for the non-relativistic approximation, the transition rates for any polarization of radiation. As an application, the first five emission lines are evaluated and compared to the X-ray emitting neutron star V0332＋53, which has multiple observable cyclotron lines, taking into account gravitational redshift. The most probable polarization is ε（2）.

关键词： stars neutron -- radiation mechanisms non-thermal -- stars magneticfields -- polarization

Relaxor behaviour and phase transition of perovskite ferroelectrics-type complex oxides(1–x)Na_(0.5)Bi_(0.5)TiO_3–xCaTiO_3 system

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Journal of Advanced Ceramics 2018年第2期7卷 124-142页

作者： Roy ROUKOs Nissrine ZAITER denis CHAUMONT Laboratoire Interdisciplinaire Carnot de Bourgogne UMR 6303 CNRs Université de Bourgogne

Polycrystalline powders of (1–x)Na_(0.5)Bi_(0.5)TiO_3–xCaTiO_3 ((1–x)NBT–xCT, 0 ≤ x ≤ 0.55) have been synthesized by solid state route. The effects of simultaneous substitution of Na^+/Bi^(3+) at A-site in NBT on structural and dielectric properties were investigated. X-ray diffraction analysis revealed the phase transition from rhombohedral structure(x = 0) to orthorhombic structure(x ≥0.15). A distinct behaviour in dielectric properties was obtained, where for x = 0, a normal ferroelectric behaviour was observed, whereas for x ≥ 0.15, a broad dielectric anomaly was revealed such that the maximum temperature(T_m) strongly depended on the frequency and shifted towards low temperature with CT. The dielectric dispersion indicated a relaxor behaviour revealed by the degree of diffuseness and modelled via Vogel–Fulcher relation. The study highlighted the relaxor behaviour as a function of frequency and proved the transformation from a relaxor high-frequency dependence to a paraelectric phase at temperature T_s. The distinct variation of the Raman spectra at room temperature was correlated with X-ray diffraction results and proved the already mentioned transition. On heating(-193–500 ℃), the Raman spectra confirmed the structural stability(Pnma) of the materials. The phonon behaviour for x = 0.15 was discussed in terms of the appearance of polar nanoregions(PNRs) into a non-polar orthorhombic matrix responsible of the relaxor behaviour. For x = 0.20, unchanged phonon behaviour confirmed the variation in dielectric behaviour where the solids transformed from a relaxor to a paraelectric state without structural phase transition.

关键词： relaxor behaviour dielectric properties Vogel–Fulcher relationship polar nanoregions (PNRs) X-ray diffraction Raman spectroscopy

situational interest impacts college students’physical activity in a design-based bike exergame

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Journal of sport and Health science 2022年第2期11卷 172-178,I0002页

作者： denis Pasco Cédric Roure school of Education University of Bourgogne Franche-ComtéBesan¸con 25000France Teaching and Research Unit in Physical Education and sport University of Teacher EducationLausanne 1014Switzerland

Background:Active videogames or exergames have been used as an innovative way to promote physical activity(PA)among various populations.A player’s interest in active videogames is associated with the fun and entertaining nature of the games and may trigger situational interest,thus increasing *** goal of this study was to examine the impact of situational interest dimensions on college students’PA when playing the design-based bike exergame Greedy Rabbit(Vescape,Berlin,Germany).Methods:sixty undergraduate students(age:20.8±1.3 years,mean±sD,18-25 years old;51.7%males)were recruited from the kinesiology department of a university located in the southern region of *** participants were assigned to an experimental group(n=41)or a control group(n=19)based on an incremental cycling *** in the experimental group engaged in 1 session of Greedy Rabbit(Vescape)while students in the control group engaged in 1 session of a placebo version of Greedy Rabbit(Vescape).The length of the sessions ranged from 24 min to 31 ***:Results for the control group indicated that the players’PA metrics(cadence:F(19,360)=1.43,p=0.11;heart rate:F(19.360)=1.16,p=0.29;oxygen consumption:F(19,360)=0.83,p=0.67)were stable during the *** for the experimental group demonstrated the effects of time on the players’PA metrics and revealed significant associations between the change in the players’situational interest dimensions and PA metrics(cadence:F(19,800)=26.30,psumption:F(19,800)=10.04,psion:An approach using a design-based exergame may be a relevant strategy for promoting levels of PA that yields positive health-related outcomes among college students.

关键词： Active videogame College students Exergame Physical activity situational interest

Pettifor maps of complex ternary two-dimensional transition metal sulfides

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npj Computational Materials 2022年第1期8卷 1692-1702页

作者： Andrea silva Jiangming Cao Tomas Polcar denis Kramer Faculty of Engineering and Physical sciences University of SouthamptonUniversity RoadSO171BJSouthamptonUK National Centre for Advanced Tribology study University of SouthamptonSouthamptonUK Faculty of Mechanical and Civil Engineering Helmut-Schmidt-Universität/Universität der Bundeswehr HamburgHolstenhofweg 8522043HamburgGermany Advanced Materials Group Department of Control EngineeringFaculty of Electrical EngineeringCzech Technical University in Prague(CTU)PragueCzech Republic Department of Heterogeneous Catalysis Helmholtz-Zentrum HereonMax-Planck-Strasse 1GeesthachtGermany

Alloying is an established strategy to tune the properties of bulk compounds for desired *** the advent of nanotechnology,the same strategy can be applied to 2D materials for technological applications,like single-layer transistors and solid *** we present a systematic analysis of the phase behaviour of substitutional 2D alloys in the Transition Metal Disulfides(TMD)*** phase behaviour is quantified in terms of a metastability metric and benchmarked against many-body expansion of the energy *** show how the metastability metric can be directly used as starting point for setting up rational search strategies in phase space,thus allowing for targeted further computational prediction and analysis of *** results presented here also constitute a useful guideline for synthesis of TMDs binary alloys via a range of synthesis techniques.

关键词： alloys sulfide behaviour

Dimuon Production from Heavy Quark Decay in Heavy-Ion Collisions at √s-5.5 TeV

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Chinese Physics Letters 1999年第7期16卷 496-498页

作者： ZHOU Dai-cui denis JOUAN LIU Han CAI Xu Institute of Particle Physics Huazhong Normal UniversityWuhan 430079 Institut de Physique Nucleairej Universite Paris-sud et IN2P3-CNRs 91406 OrsayFrance

The production of heavy-Havor quark c(c)and b(b)in pp collisions is described under perturbative quantum chromodynamics framework,the extrapolation from hadron-hadron up to nucleus-nucleus collisions is based on geometrical model by taking into account the nucleus shadowing *** simulate the heavy quark production,the decay to dilepton and effects of detection and analysis technique of the pairs,and predict the muon rate and the invariant mass spectrum of dimuons that could be detected in forward region in Pb-Pb collisions at large hadron collider energies.

关键词： effect. quark hadron

Hybrid swarm Intelligence Based Qos Aware Clustering with Routing Protocol for WsN

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Computers, Materials & Continua 2021年第9期68卷 2995-3013页

作者： M.s.Maharajan T.Abirami Irina V.Pustokhina denis A.Pustokhin K.shankar Department of Computer science and Engineering GRT Institute of Engineering and TechnologyTiruttani631209India Department of Information Technology Kongu Engineering CollegeErode638060India Department of Entrepreneurship and Logistics Plekhanov Russian University of EconomicsMoscow117997Russia Department of Logistics State University of ManagementMoscow109542Russia Department of Computer Applications Alagappa UniversityKaraikudi630001India

Wireless sensor Networks(WsN)started gaining attention due to its wide application in the fields of data collection and information *** recent advancements in multimedia sensors demand the Quality of service(Qos)be maintained up to certain *** restrictions and requirements in Qos management completely depend upon the nature of target *** of the major Qos parameters in WsN are energy efficiency,network lifetime,delay and *** this scenario,clustering and routing are considered as the most effective techniques to meet the demands of *** they are treated as NP(Non-deterministic Polynomial-time)hard problem,swarm Intelligence(sI)techniques can be *** current research work introduces a new Qos aware Clustering and Routing-based technique using swarm Intelligence(QosCRsI)*** proposed QosCRsI technique performs two-level clustering and proficient ***,the fuzzy is hybridized with Glowworm swarm Optimization(GsO)-based clustering(HFGsOC)technique for optimal selection of Cluster Heads(CHs).Here,Quantum salp swarm optimization Algorithm(QssA)-based routing technique(QssAR)is utilized to select the possible routes in the *** order to evaluate the performance of the proposed QosCRsI technique,the authors conducted extensive simulation analysis with varying node *** experimental outcomes,obtained from the proposed QosCRsI technique,apparently proved that the technique is better compared to other state-of-the-art techniques in terms of energy efficiency,network lifetime,overhead,throughput,and delay.

关键词： Quality of service clustering routing energy efficiency wireless sensor networks swarm intelligence

An Intelligent Deep Learning Based Xception Model for Hyperspectral Image Analysis and Classification

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Computers, Materials & Continua 2021年第5期67卷 2393-2407页

作者： J.Banumathi A.Muthumari s.Dhanasekaran s.Rajasekaran Irina V.Pustokhina denis A.Pustokhin K.shankar Department of Information Technology University College of EngineeringNagercoil629004India Department of Computer science and Engineering University College of EngineeringRamanathapuram623513India Department of Computer science and Engineering Kalasalingam Academy of Research and EducationKrishnankoil626128India Department of Electrical Engineering PSN College of EngineeringTirunelveli627152India Department of Entrepreneurship and Logistics Plekhanov Russian University of EconomicsMoscow117997Russia Department of Logistics State University of ManagementMoscow109542Russia Department of Computer Applications Alagappa UniversityKaraikudi630001India

Due to the advancements in remote sensing technologies,the generation of hyperspectral imagery(HsI)gets significantly *** classification of HsI becomes a critical process in the domain of hyperspectral data *** massive availability of spectral and spatial details of HsI has offered a great opportunity to efficiently illustrate and recognize ground ***,deep learning(DL)models particularly,convolutional neural networks(CNNs)become useful for HsI classification owing to the effective feature representation and high *** this view,this paper introduces a new DL based Xception model for HsI analysis and classification,called Xcep-HsIC ***,the presented model utilizes a feature relation map learning(FRML)to identify the relationship among the hyperspectral features and explore many features for improved classifier ***,the DL based Xception model is applied as a feature extractor to derive a useful set of features from the FRML *** addition,kernel extreme learning machine(KELM)optimized by quantum-behaved particle swarm optimization(QPsO)is employed as a classification model,to identify the different set of class *** extensive set of simulations takes place on two benchmarks HsI dataset,namely Indian Pines and Pavia University *** obtained results ensured the effective performance of the XcepHsIC technique over the existing methods by attaining a maximum accuracy of 94.32%and 92.67%on the applied India Pines and Pavia University dataset respectively.

关键词： Hyperspectral imagery deep learning xception kernel extreme learning map parameter tuning

Inherent Complexities of a Multi-stakeholder Approach to Building Community Resilience

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International Journal of Disaster Risk science 2020年第1期11卷 32-45页

作者： Josephine Adekola denis Fischabcher-smith Moira Fischabcher-smith Finance Accounting and RiskGlasgow Caledonian UniversityGlasgow G40BAScotlandUK College of social sciences University of GlasgowGlasgow G128QQScotlandUK

Enhancing community resilience has increasingly involved national and regional governments adopting a multi-stakeholder approach because of the potential interagency benefits. This has led to questions about how best to involve stakeholder groups in translating community resilience policies into practice. This exploratory study contributes to this discussion by addressing two key areas that are fundamental in the concerted effort to build community resilience to natural hazards:(1) stakeholder understanding of community resilience as a concept;and(2) the difficulties associated with the processes of risk assessment and preparedness that stakeholders face locally in building community resilience. Data were collected through semistructured interviews with 25 practitioners and experts within scotland’s resilience community, and were analyzed through an inductive approach to thematic analysis. These data show how the interpretation of community resilience differs across stakeholder groups. Analysis of the data reveals challenges around the nature of the risk assessment and its role in shaping risk perception and communication. significant complications occur in communicating about low probability-high consequence events, perceived territoriality, competing risk prioritizations, and the challenges of managing hazards within a context of limited resources. The implications of these issues for policy and practice are also discussed.

关键词： Community disaster preparedness Community resilience Multi-stakeholder approach Natural hazards Risk assessment