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Micromagnetics and Signal Analysis of Shielded Spin-Valve Multilayer

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Chinese Physics Letters 1996年第6期13卷 469-472页

作者： ZhANG huai-wu YANG Shi-qing LIU Ying-li WANG hao-cai h.J.Kim Institute of Materials and Information Engineering University of Electronic Science and TechnologyChengdu 610054 Magnetic Alloy Laboratory Metals DivisionKorea Institute of Science and TechnologyP.O.Box 131ChenogryangSeoulKorea

In order to linearize a spin-valve giant magnetoresistance head,the exchanges layer sputtered at fringe area or a permanent magnet layer longitudinal biasing for domain stabilization based on a physical calculated model may be *** correlations between the head performance characteristic and head geometric parameters have been simulated by putting the head on a suitable front-end electric *** simulative results show that the optimal sensing current is from 10 to 40mA and the linear geometric parameteres for gap width are at the range of G_(1)+G_(2)≤0.5μm.

关键词： stabilization permanent Signal

On the Supercyclicity and hypercyclicity of the Operator Algebra

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Acta Mathematica Sinica,English Series 2008年第7期24卷 1221-1232页

作者： b.YOUSEFI h.REZAEI Department of Mathematics College of SciencesShiraz UniversityShiraz 71454Iran and Department of MathematicsPayame-Noor UniversityIran

Let b（X） be the operator algebra for a separable infinite dimensional hilbert space h, endowed with the strong operator topology or ＊-strong topology. We give sufficient conditions for a continuous linear mapping L ： b（X） →b（X） to be supercyclic or ,-supercyclic. In particular our condition implies the existence of an infinite dimensional subspace of supercyclic vectors for a mapping T on h. hypercyclicity of the operator algebra with strong operator topology was studied＇ by Chan and here we obtain an analogous result in the case of ＊-strong operator topology.

关键词： operator algebra,*-strong topology strong operator topology hypercyclicity criterion supercyclicity criterion

EFFECTS OF LIQUID COMPRESSIbILITY ON RADIAL OSCILLATIONS OF GAS bUbbLES IN LIQUIDS

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Journal of hydrodynamics 2012年第5期24卷 760-766页

作者： ZhANG Yu-ning LI Sheng-cai School of Engineering University of Warwick Coventry UK CV4 7AL

For forced radial oscillations of gas bubbles in liquids, a more rigorous expression of the acoustic damping constant based on Keller＇s equation is developed. Comparison with those in published papers is also made. The expression offered in this paper will improve the predictions of total damping constant in particular for high frequencies and large bubbles, i.e., large ωR0 / c1 （ ω is the frequency of driving sound field, Ro is the equilibrium bubble radius, c1 is the sound speed in the liquid）. Examples in ultrasound imaging and acoustical oceanography are demonstrated.

关键词： gas bubble damping constant liquid compressibility natural frequency

Civil unmanned aircraft system operation in national airspace: A survey from Air Navigation Service Provider perspective

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Chinese Journal of Aeronautics 2021年第3期34卷 200-224页

作者： Zhaoxuan LIU Kaiquan cai Yanbo ZhU School of Electronics and Information Engineering Beihang UniversityBeijing 100083China Aviation Data Communication Corporation Beijing 100083China

Unmanned Aircraft Systems(UASs) have advanced technologically and surged exponentially over recent years. Currently, due to safety concerns, most civil operations of UAS are conducted in low-level uncontrolled area or in segregated controlled airspace. As the industry progresses, both operational and technological capabilities have matured to the point where UASs are expected to gain greater freedom of access to both controlled and uncontrolled airspace. Extensive technical and regulatory surveys have been conducted to enable the expanded operations. however, most surveys are derived from the perspective of UAS own operating mechanism and barely consider interactions of their non-segregated activities with the Air Traffic Management(ATM) system. hence, to fill the gap, this paper presents a survey conducted from the perspective of Air Navigation Service Provider(ANSP), which serves to accommodate these new entrants to the overall national airspace while continuing flight safety and efficiency. The primary objectives of this paper are to:(A) describe what typical ANSP-supplied UAS Traffic Management(UTM) architecture is required to facilitate all types of civil UAS operations;(b) identify three major ANSP considerations on how UAS can be accommodated safely in civil airspace;(C) outline future directions and challenges related with UAS operations for the ANSP.

关键词： Air Navigation Service Provider Airspace Organization and Management Air Traffic Control Air Traffic Management Air traffic service provision Unmanned Aircraft System UAS Traffic Management

Review on Optimization of Nuclear Power Development:A Cyber-Physical-Social System in Energy Perspective

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Journal of Modern Power Systems and Clean Energy 2022年第3期10卷 547-561页

作者： Xinxin Yang bin cai Yusheng Xue School of Electrical Engineering Southeast UniversityNanjingChina State Grid Electric Power Research Institute(NARI Group Corporation) NanjingChina State Key Laboratory of Smart Grid Protection and Operation Control NanjingChina

Nuclear power development is a complex issue spanning cyber,physical,and social systems that is essential to achieving energy security and climate *** the ongoing worldwide trend towards carbon neutrality,the positioning of nuclear power in energy mix should be *** paper aims to present a systematic review of current research on optimization of nuclear power *** concept of cyber-physical-social system in energy(CPSSE)is adopted,which provides a suitable perspective and enables the review of relevant studies to achieve some novel *** on the CPSSE,firstly,a research framework is established and the main research elements in optimization are identified,followed by a proposed conceptual risk-based optimization ***,current studies are analyzed and classified into four categories according to the research *** status quo and limitations are *** is found that the research results of nuclear-specific issues have not been well integrated into the optimization of nuclear *** a relatively reliable power supply,nuclear power is capable of maintaining power and electricity adequacy of the whole system,especially in the case of power shortage caused by long-period low output of renewable energy or extreme external *** superiority should not be ignored in the *** critical factors that should be further considered include disruptive technologies,nuclear safety,energy policies,and stakeholder ***,suggestions are given for future research.

关键词： Carbon emission carbon neutrality cyber-physical-social system in energy(CPSSE) comprehensive evaluation dynamic interactive hybrid simulation energy transition multi-objective optimization

PSO-ACSC:a large-scale evolutionary algorithm for image matting

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Frontiers of Computer Science 2020年第6期14卷 31-42页

作者： Yihui LIANG han hUANG Zhaoquan cai School of Computer Science University of Electronic Science and Technology of ChinaZhongshan InstituteZhongshan 528400China School of Software Engineering South China University of TechnologyGuangzhou 510006China Research Department Huizhou UniversityHuizhou 516007China

Image matting is an essential image processing technology due to its wide range of ***-based image matting is one of the main branches of image matting research that estimates alpha mattes by selecting the best pixel *** is essentially a large-scale multi-peak optimization problem of pixel *** study shows that particle swarm optimization(PSO)can effectively optimize the pixel ***,it still suffers from premature convergence problem which often occurs in pixel pair optimization that involves a large number of local *** address this problem,this work presents a parameter-free strategy for PSO called adaptive convergence speed controller(ACSC).ACSC monitors and conditionally controls the particles by competitive pixel pair recombination operator(CPPRO)and pixel pair reset operator(PPRO)during the *** performs CPPRO to improve the competitiveness of a particle when the performance of most of the pixel pairs is worse than that of the best-so-far *** is performed to avoid premature convergence when the alpha mattes regarding two selecleu particles ae liglly *** results show that ACSC significantly enhances the performance of PSO for image matting and provides competitive alpha mattes comparing with state-of-the-art evolutionary algorithms.

关键词： evolutionary computing particle swarm optimization large-scale optimization image matting

Preparation and reaction mechanism of novel Ce_(x)Co_(y)Cuz oxide composite catalysts towards oxidation of o-xylene

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Journal of Rare Earths 2022年第10期40卷 1573-1583页

作者： Mengge Zhao Weijian cai Jiwu Li School of Environmental Science and Engineering Zhejiang Gongshang UniversityHangzhou 310018China Department of Chemistry School of Food Science and BiotechnologyZhejiang Gongshang UniversityHangzhou 310018China

Ce_(x)Co_(y)Cuzoxide composite catalysts were prepared by using polyethylene glycol, citrate sol-gel method combined with PMMA template for the oxidation of o-xylene. The catalysts were characterized by the Xray diffraction(XRD), h2-temperature programmed reduction(h2-TPR), X-ray photoelectron spectroscopy(XPS) and Fourier transform infrared spectroscopy(FT-IR), etc. The catalytic activity for o-xylene was investigated. The catalytic degradation pathway and mechanism of o-xylene were inferred. The results show that Ce O_(2)is mainly present on the surface of all catalysts. The surface area of Ce_(2)Co1Cu1is up to 77.2 m^(2)/g, and the average pore size is 10.62 nm. It exhibits redox and sufficient Ce^(4+)and Ce^(^(3+)), and reactive oxygen species, and has maximum O-h and C=O in the five catalyst samples. The catalytic activity of Ce2Co1Cu1is the best at low temperature, with the T50and T90values of 235 and 258°C at a space velocity of 32000 h-1, respectively. The o-xylene is oxidized to o-methyl benzaldehyde, and then further oxidized to o-methylbenzoic acid, and finally CO_(2)and h2O are formed.

关键词： Ce_(x)Co_(y)Cuz composite oxide catalyst Polyethylene glycol Citrate sol-gel method Catalytic activity o-xylene Rare earths

Systematic diesel molecular performance evaluation based on quantitative structure-property relationship model

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Petroleum Science 2022年第2期19卷 809-818页

作者： Guang-Qing cai Lin-Zhou Zhang State Key Laboratory of heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing 102249China

The production and separation of optimal molecules in diesel fuels require a systematic property evaluation for the containing *** paper evaluates the diesel molecules based on four key quality indicators:low-temperature fluidity,cleanliness,ignition,and power *** established the corresponding quantitative structure-property relationship models for corresponding properties,which are freezing point,yield sooting index,cetane number,and combustion *** models were applied for the screening of the high-performance molecules that is suitable for *** molecular performance distribution of the conventional diesel and biodiesel were also ***,we analyzed the effect of different transformation paths on molecular properties,giving guidance on the conversion process design.

关键词： Diesel Optimal molecules QSPR Molecular screening

Numerical investigation and optimisation of heat transfer performance in a vertical sinter cooling packed bed using Taguchi and ANOVA methods

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Journal of Iron and Steel Research International 2020年第8期27卷 898-912页

作者： Jun-peng Fu Jiu-ju cai Department of Thermal Engineering SEP Key Laboratory of Eco-IndustrySchool of MetallurgyNortheastern UniversityShenyang 110819LiaoningChina

The Taguchi and analysis of variance (ANOVA) methods were applied to investigate the effects of the structural and operational parameters on the heat transfer performance of a vertical sinter cooling packed bed. The analysed parameters were the gas flow rate, the air inlet temperature, the sinter inlet temperature, the cooling bed diameter and the cooling bed height, all of which contain three levels. The purpose was to improve the heat transfer performance of a vertical sinter cooling bed. A numerical analysis model was established to assess the heat transfer performance with respect to the varying parameters and their different levels. This mathematical model was validated by using data from practical industrial processes. The Taguchi method for the L27 (35) orthogonal design experiment was selected to evaluate the impacts of the design parameters on the heat transfer performance and to acquire the optimum combination of parameters. The analysis of variance was applied to assess the impact weights and the order of significance of the design parameters. The results show that the sinter inlet temperature and cooling bed diameter have great influences and impact the exergy of the wasted heat recovery by 61.65% and 23.31%, respectively. however, the gas flow rate and the air inlet temperature have small effects on the response. Furthermore, the air and sinter inlet temperatures have the most significant impacts on the efficiency of heat transfer by 68.83% and 23.31%, respectively. The optimal parameter combination (A1b1C3D3E3) was obtained, and the optimal results were validated by confirmation tests.

关键词： Vertical sinter packed bed Wasted heat recovery Taguchi method Analysis of variance(ANOVA) Gas–solid heat transfer