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Chirping instabilities produced by a runaway electron beam at a spherical tokamak

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Plasma Science and Technology 2023年第7期25卷 19-24页

作者： I M BALACHEnKOv.n.n BAKHAREv v K GUSEv M v ILIASOvA E M KHILKEvICH P S KOREnEv A E KOnKOv v B MInAEv Yu v MITRIZHKIn M I PATROv Yu v PETROv.n.v SAKHAROv A E SHEvELEv O M SKREKEL Ioffe Institute Saint-Petersburg 194021Russia Lomonosov Moscow State University Moscow 119991Russia

Two different types of MHD instabilities with rapidly chirping frequency were found to arise in the Globus-M2 spherical tokamak in substantially different frequency *** first type arises at frequencies of an order of 1 MHz in ohmic plasmas at relatively low density(n_(e))n a wide range of toroidal magnetic fields and plasma *** type of instability was identified as compressional Alfv.n.waves,driv.n.by electrons,accelerated during a sawtooth *** was found that the mode frequency is sweeping in time,according to the Berk-Breizman hole-clump nonlinear chirping *** second type of wave arises in a specific single-swing regime of the central solenoid current with a very narrow plasma column,when the plasma tends to decay at extremely low density(n_(e))nd,in fact,is an instability of the runaway electron *** exited modes cover the whole observed frequency range and are divided into several(two or three)frequency regions:approximately 0-30 MHz,60-120 MHz and sometimes 30-60 *** of the branches was also *** chirps are more rapid than for 1 MHz Alfv.n.instability and follow an exponential *** paper,to our knowledge,is the first report of frequency chirping instabilities excited by accelerated electrons at a spherical tokamak.

关键词： Alfv.n.waves chirping instability spherical tokamak runaway electrons

On REDUCTIOn OF MULTICOMPOnEnT COSMOLOGY TO TODA LATTICE

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Chinese Physics Letters 1990年第3期7卷 97-100页

作者： v.D.Ivashchuk v.n.Melnikov USSR State Committee for Standards 9 Leninsky prospectMoscow 117049USSR

We prove that Gibbons-Maeda reduction of two-component cosmology to the Toda lattice can not be generalyzed for n-component case.

关键词： MULTI lattice component

Unsupervised intrusion detection system for in-vehicle communication networks

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Journal of Safety Science and Resilience 2024年第2期5卷 119-129页

作者： Kabilan n v.n.yakumar Ravi v Sowmya Center for Computational Engineering and networking(CEn) Amrita School of Artificial InteligenceAmrita Vishwa VidyapeethamCoimbatoreIndia Center for Artificial Intlligence Prince Mohammad Bin Fahd UniversityKhobarSaudi Arabia

In-vehicle communication has been optimized day to day to keep updated of the *** area network(CAn)is used as a standard communication method because of its efficient and reliable ***,CAn is prone to several network level attacks because of its lack in security *** methods have been introduced to incorporate this in *** proposed an unsupervised method of intrusion detection for in-vehicle communication networks by combining the optimal feature extracting ability of autoencoders and more precise clustering using fuzzy C-means(FCM).The proposed method is light weight and requires less computation *** performed an extensive experiment and achieved an accuracy of 75.51%with the ML35o in-vehicle intrusion *** experimental result,the proposed method also works better for other intrusion detection problems like wireless intrusion detection datasets such as WnS-DS with accuracy of 84.05%and network intrusion detection datasets such as KDDCup with accuracy 60.63%,UnSW_nB15 with accuracy 73.62%and Information Security Center of Excellence(Iscx)with accuracy 74.83%.Overall,the proposed method outperforms the existing methods and avoids labeled datasets when training an in-vehicle intrusion detection *** results of the experiment of our proposed method performed on various intru-sion detection datasets indicate that the proposed approach is generalized and robust in detecting intrusions and can be effectively deployed in real time to monitor CAn traffic in vehicles and proactively alert during attacks.

关键词： Controlarea network Intrusiondetection Unsupervised learning Autoencoders Fuzzy C-means

Resistance in hybrid derivatives of Lycopersicon accessions against leaf caterpillar, Spodoptera litura Fab.

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Insect Science 2008年第2期15卷 141-146页

作者： n. Muthukumaran v. Selv.n.rayanan Department of Entomology Faculty of Agriculture Annamalai University Annamalainagar Tamil Nadu India

Four tomato accessions, namely Ac 238, Roma, Seijima Jeisei and varushanadu Local selected from preliminary screening of 321 accessions and their hybrid derivatives, namely HYtF：（varushanadu Local × Ac 238）, HY2F1（varushanadu Local × Roma）, HY3F1 （Ac 238 × Roma）（first generation）, HY1F2, HY2F2 and HY3F2 （second generation） were evaluated for their resistance in comparison with a susceptible check, 1979 against the leaf caterpillar, Spodoptera litura Fab. both under field and laboratory conditions at Annamalainagar, Tamil nadu, India. In the field evaluation, accession Seijima Jeisei and hybrid HY3F1 recorded the minimum larval population. In glasshouse and laboratory studies, Seijima Jeisei was the least preferred by S. litura for both feeding and oviposition. The hybrid HYsF： exerted pronounced antibiosis effect on S. litura. Among the various biophysical and biochemical bases of resistance, contents of reducing sugar and phenol were found negatively correlated with S. litura larval feeding. Among the hybrids, HY3F1 and HY3F2 and the parent Seijima Jeisei recorded higher fruit yield per plant in both seasons. Considerable variation in the resistance traits of the hybrids was observed when compared with the parents.

关键词： hybrid derivatives resistance Spodoptera litura tomato accession

Modeling large reversible electric-field-induced strain in ferroelectric materials using 90° orientation switching

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Science China(Technological Sciences) 2009年第1期52卷 141-147页

作者： Roderick v. n. MELnIK Mathematical Modelling and Computational Sciences Wilfrid Laurier University Waterloo 75 University Ave W Canada N2L 3C5

Reversible large electric-field-induced strain caused by reversible orientation switchings in BaTiO3 is modeled using the Landau's theory of phase transition. A triple well free energy function is constructed. Each of its minima is associated with one of the polarization orientations involved. nonlinear constitu- tive laws accounting for reversible orientation switchings and electrostriction effects are obtained by using thermodynamic equilibrium conditions. Hysteretic dynamics of one-dimensional structures is described by coupled nonlinear differential equations. Double hysteretic loops in the electric and me- chanic fields are both successfully modeled. Giant reversible electrostriction is modeled as a conse-quence of reversible orientation switchings via electro-mechanical couplings. Comparisons with ex-perimental results reported in literatures are presented.

关键词： large electrostriction reversible switchings double hysteresis differential model

Microorganisms in the Zone of Submarine volcanic Eruptions at 535-513 Ma

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American Journal of Plant Sciences 2014年第15期5卷 2464-2471页

作者： Petr n. kolosov Lena S. Sofroneeva Diamond and Precious Metals Geology Institute SB RAS Yakutsk Russia

new anatomical features revealed in some Early Cambrian calcareous microfossils suggest comparison with Rhodophyta (red algae), which makes it possible to define their taxonomic position. A taxonomically rich Early Cambrian paleobiocoenosis has been discovered in northern Tien Shan, which exemplifies the existence on earth at 535-513 Ma (million years) of morphologically complex fungiform microorganisms and red algae in a shallow-water biotope where environmental conditions favorable for life were created as a result of submarine volcanic eruptions.

关键词： Calcareous Microfossil Tetraspore Tetrasporangium Rhodophyta Cambrian volcanicity Paleobiocoenosis Tien Shan

Quantum dynamics of charge transfer on the one-dimensional lattice:Wave packet spreading and recurrence

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Chinese Physics B 2016年第1期25卷 817-830页

作者： v.n.Likhachev O I Shevaleevskii G A v.n.gradov Emanuel Institute of Biochemical Physics Russian Academy of Sciences

The wave function temporal evolution on the one-dimensional （ID） lattice is considered in the tight-binding approxi- mation. The lattice consists of n equal sites and one impurity site （donor）. The donor differs from other lattice sites by the on-site electron energy E and the intersite coupling C. The mov.n. wave packet is formed from the wave function initially localized on the donor. The exact solution for the wave packet velocity and the shape is derived at different values E and C. The velocity has the maximal possible group velocity v = 2. The wave packet width grows with time -t1/3 and its amplitude decreases ,- t-1/3. The wave packet reflects multiply from the lattice ends. Analytical expressions for the wave packet front propagation and recurrence are in good agreement with numeric simulations.

关键词： quantum dynamics tight-binding approximation charge transport

Dynamics of acousto-rheological properties of polymerized materials on their solidification

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Rare Metals 2007年第S1期26卷 1-4页

作者： RIMLYAnD v I BAKHAnTSOv A v STARIKOvA v n Physics Department Automation of Physical and Technical Measurements LaboratoryPacific National University

An automated system was designed to study in a continuous regime the rheological properties of the care polymeric compositions using the damped vibration *** a parallel mode measurements of rheological and acoustic characteristics of the care compositions were made on the basis of epoxy *** of shear modulus,viscosity,the sound speed,and the damping coefficient as functions of polymerization were *** of spectral characteristics of acoustic signals in the polymerization were *** of the experimental results obtained reveals that the dynamics of the variation of acoustic and rheological properties is significantly *** major change of acoustic characteristics occurs in the initial stage of the solid state formation when a transition from a liquid-to-gel like state takes *** characteristics vary dramatically at the crossover from a high-viscosity to solid *** the frequency dependencies of an acoustic signal a number of essential features were observed.

关键词： viscosity acoustic properties shear modulus polymerization composition

Influence of high-temperature convective flow on viability of Scots pine needles(Pinus sylvestris L.)

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Journal of Forestry Research 2020年第5期31卷 1489-1497页

作者： I.G.Gette n.v.Pakharkova I.v.Kosov I.n.Bezkorovaynaya Siberian Federal University 79 SvobodnyKrasnoyarskRussia 660041 Sukachev Institute of Forest SB RAS Federal Research Center “Krasnoyarsk Science Center of SB RAS”50 AkademgorodokKrasnoyarsk 660036Russia

During a forest fire,plants are affected by high temperatures causing *** the time of burning,it is difficult to record temperature changes in tree crowns and the associated effects on *** paper presents the results of modelling a high-temperature effect simulating a convective flow from a ground *** of the response was carried out by the parameters of rapid fluorescence(Fv/Fm,ETR),the state of the pigment complex,and the relative water content in the *** characterize the degree of heat endurance and short-term effects concerning thermal damage,saplings of Scots pine(Pinus sylvestris L.)were used at different times during the growing season(June,July,August,September).Experimental heating at 55℃ lasted for 5 and 10 *** were different levels of heat resistance by the *** in June show that heating of the saplings significantly suppressed *** July,August,and September,the photochemical quantum yield(Fv/Fm)was restored to 75%and 60%from the initial level after 5-and 10-min heating,*** electron transport rate(ETR)for saplings in September was restored to their initial level within 3 days after a short heat *** of the photosynthetic activity in needles was observed after a 5-min impact,but by the end of the study period,restoration had not reached control values.A longer heating of 10 min resulted in an irreversible suppression of photosynthesis and destruction of the photosynthetic apparatus,as evidenced by the decrease in the number of photosynthetic pigments.

关键词： Pinus sylvestris Heat stress Chlorophyll Fluorescence Forest fires