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Journal of Advanced Ceramics 2022年第3期11卷 504-514页

作者： Qi CAO Jie ZHANG Huibin ZHANG Junzhou XU Renchao che Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

Cobalt diselenide(Cose_(2))hierarchical clew-like structure is synthesized via a dual-surfactant templated hydrothermal process,and for the first time,its microwave absorption capability has been ***,the as-synthesized hierarchical interconnected structure is assembled by numerous dense *** tuning of the synthetic conditions which could influence the hierarchical architecture indicates that,in this system,cetyltrimethylammonium bromide(CTAB)plays a dominate role of“balling”while protonated diethylenetriamine(DETA)plays the role of“stringing”.As a novel absorbent,the microwave absorption performance of Cose_(2)microstructure is evaluated in 2–18 GHz ***,3D hierarchical Cose_(2)microclews exhibit superior minimum reflection loss of−26.93 dB at 7.28 GHz and effective absorption bandwidth of 3.72 GHz,which are∼120%and∼104%higher than those of simple Cose_(2)nanosheets,*** drastic enhancement could be attributed to the large specific surface area,and more dissipation channels and scattering sites enabled by the unique clew-like *** versatile dual-surfactant templated assembly of hierarchical Cose_(2)microstructure,along with its appreciable dielectric microwave absorption performance,provides new inspirations in developing novel microwave absorbents for mitigation of electromagnetic pollution.

关键词： hierarchical structure cobalt diselenide surfactant assembly absorption

Monitoring the frozen duration of Qinghai Lake using satellite passive microwave remote sensing low frequency data

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Chinese science Bulletin 2009年第13期54卷 2294-2299页

作者： che Tao LI Xin JIN Rui Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 710000 China

The Qinghai Lake is the largest inland lake in *** significant difference of dielectric properties between water and ice suggests that a simple method of monitoring the Qinghai lake freeze-up and break-up dates using satellite passive microwave remote sensing data could be *** freeze-up and break-up dates from the Qinghai Lake hydrological station and the MODIs L1B reflectance data were used to validate the passive microwave remote sensing *** validation shows that passive microwave remote sensing data can accurately monitor the lake *** uncertainty comes mainly from the revisit frequency of satellite *** data from 1978 to 2006 show that lake ice duration is reduced by about 14―15 *** freeze-up dates are about 4 days later and break-up dates about 10 days *** regression analyses show that,at the 0.05 significance level,the correlations are 0.83,0.66 and 0.89 between monthly mean air temperature(MMAT) and lake ice duration days,freeze-up dates,break-up dates,***,inter-annual variations of the Qinghai Lake ice duration days can significantly reflect the regional climate variation.

关键词：被动微波遥感遥感数据冻结卫星期限监测 MODIs数据低频

Recommending Personalized POIs from Location Based social Network

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Journal of Beijing Institute of Technology 2018年第1期27卷 137-145页

作者： Haiying che Di sang Billy Zimba school of software Beijing Institute of Technology

Location based social networks（ LBsNs） provide location specific data generated from smart phone into online social networks thus people can share their points of interest（ POIs）. POI collections are complex and can be influenced by various factors,such as user preferences,social relationships and geographical influence. Therefore,recommending new locations in LBsNs requires to take all these factors into consideration. However,one problem is how to determine optimal weights of influencing factors in an algorithm in which these factors are combined. The user similarity can be obtained from the user check-in data,or from the user friend information,or based on the different geographical influences on each user＇s.che.k-in activities. In this paper,we propose an algorithm that calculates the user similarity based on check-in records and social relationships,using a proposed weighting function to adjust the weights of these two kinds of similarities based on the geographical distance between users. In addition,a non-parametric density estimation method is applied to predict the unique geographical influence on each user by getting the density probability plot of the distance between every pair of user＇s.che.k-in locations. Experimental results,using foursquare datasets,have shown that comparisons between the proposed algorithm and the other five baseline recommendation algorithms in LBsNs demonstrate that our proposed algorithm is superior in accuracy and recall,furthermore solving the sparsity problem.

关键词： location based social network personalized geographical influence location recommendation non-parametric probability estimates

Towards a Fair World Trade Regime——The Role of s & D Treatment Revisited

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国际经济法学刊 2004年第4期11卷 19-45页

作者： che Pizhao Du Ming Professor of the Law school of Tsinghua University Graduate student of the Law school of Tsinghua University.

This article discusses the fairness issue of WTO trade *** starts from the point that fairness is one of the policy goals that WTO trade law should ***,due to the intrinsical disadvantages of the developing countries in their participation in the world trade system,non-discrimination principle of WTO may lead to unfair *** & Differential Treatment in WTO trade law is a kind of corrective means of *** article conducts a historical and normative survey of special & Differential Treatment and reveals that these rules have not played their proper role in establishing a fair trade *** authors then put forward their suggestions for WTO trade law to be more fair and explore some problems inherently in special & Differential Treatment.

关键词： WTO trade law Fairness Participation

Engineering the electronic structure on MXenes via multidimensional component interlayer insertion for enhanced electromagnetic shielding

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Journal of Materials science & Technology 2023年第7期138卷 149-156页

作者： Mengqiu Huang Lei Wang Biao Zhao Guanyu chen Renchao che Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsDepartment of Materials ScienceFudan UniversityShanghai 200438China Joint-Research Center for Computational Materials Zhejiang LaboratoryHangzhou 311100China

MXene-based functional electromagnetic interference(EMI)shielding films are highly desirable for mod-ern integrated electronic and telecommunication systems in aerospace,military,artificial intelligence,and smart and wearable electronics *** this work,3D freestanding Ti_(3)C_(2)T_(x)/CNTs/Ni film assembled by 1D multi-walled carbon nanotubes(MWCNTs)/Ni and 2D Ti_(3)C_(2)T_(x)MXene sheets was synthesized by a facile vacuum filtration *** electrostatic incorporation,hexagonal nickel plates embed on the CNTs and then the CNTs/Ni insert into the Ti_(3)C_(2)T_(x)layers to form magnetized Ti_(3)C_(2)T_(x)-based functional film with a compact and laminated *** to the outstanding electron migration capacity in the highly conductive Ti_(3)C_(2)T_(x)sheet and multiple internal reflections from porous and segregated structures,the op-timized Ti_(3)C_(2)T_(x)/CNTs/Ni composite films show excellent EMI shielding effectiveness of 67.4 dB with elec-trical conductivity of 744 s cm^(-1).surprisingly,a magnetization compensation strategy is built to boost the EMI shielding effectiveness with decreased ***,the visual magnetic coupling phenomenon and charge distribution in the heterogeneous interfaces could be observed in the recon-structed electron holography *** encouraging results shed light on novel magnetized MXene-based functional films for high-performance EMI shielding.

关键词： Ti_(3)C_(2)T_(x)MXene Magnetic modulation Electromagnetic-interference shielding Nickel flakes Freestanding film

Observer-based H-infinity control in multiple channel networked control systems with random packet dropouts

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控制理论与应用（英文版） 2010年第3期8卷 359-367页

作者： Weiwei che Jianliang WANG Guanghong YANG school of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 school of Information science and Engineering Northeastern University Shenyang Liaoning 110004 China

This paper investigates the observer-based H-infinity control problem for networked control systems （NCss） with random packet dropouts. A general packet dropout model with multiple independent stochastic variables in the multiple channels case is adopted to describe the data missing in the limited communication channels. With the consideration of the sensor-to-controller and controller-to-actuator packet dropouts at the same time, a new method is pro- posed based on a separation lemma to design an observer-based H-infinity controller, which exponentially stabilizes the closed-loop system in the sense of mean square and also achieves a prescribed H-infinity disturbance attenuation level. A numerical example is given to illustrate the effectiveness of the proposed control method.

关键词： Networked control system (NCs) H-infinity control separation lemma Random packet dropouts LMI

Research on stabilizing and tracking control system of tracking and sighting pod

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控制理论与应用（英文版） 2012年第1期10卷 107-112页

作者： shanzhong LIU Hong che Longhe sUN Electronic Information Engineering College Henan University of Science ＆ Technology Luoyang Henan 471003 China The 613th Research Institute of Aviation Industry Corporation of China Luoyang Henan 471009 China

With the coupling among three-axis platform frames of tracking and sighting pod taken into considera- tion, the kinetic equations are set up according to the kinetic characteristic. Moreover, by predigesting the equations, the math model suitable for controller design is gained. An H-infinity controller combining with Kalman filter is designed for stabilizing loop of tracking and sighting pod platform frames. Fuzzy PID controllers corresponding to each tracking loop of three-axis frames are designed. The control system designed in this study, in which the effects of the coupling among frames and parameters variation are taken into consideration, is closer to practical situation. The control system is dynam- ically simulated under the condition of multidisturbance. The simulation results show that the entire stabilization tracking control system has good robustness and high tracking precision, which fulfils the need of stabilizing and tracking control of trackin~ and si^htin~ pod.

关键词： Tracking and sighting pod Modeling Robustness Fuzzy PID control H-infinity control

Experimental study on influence of operating parameters on tar components from corn straw gasification in fluidized bed

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Frontiers in Energy 2021年第2期15卷 374-383页

作者： shuai GUO Xiao WEI Deyong che Hongpeng LIU Baizhong sUN school of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

Gasification is a promising approach for converting solid fuel sources, including renewable ones like biomass, for use. The main problem in biomass gasification is the formation of condensable tars, including polycyclic aromatic hydrocarbons (PAHs). This paper investigated the conversion of tar components during corn straw gasification. It analyzed collected tar components using a gas chromatograph-mass spectrograph (GC-Ms). Experimental results indicate that, with increasing temperature from 700°C to 900°C, the concentrations of benzene, indene, phenanthrene, naphthalene, acenaphthylene, fluorene, and pyrene increased whereas those of toluene, phenol, 1-methylnaphthalene, and 2-methylnaphthalene decreased. As the equivalence ratio (ER) increased from 0.21 to 0.34, the concentrations of indene and phenanthrene increased from 0.148% and 0.087% to 0.232% and 0.223%, respectively. Further, the phenol content increased as ER increased from 0.21 to 0.26 and then decreased as the ER increased further to 0.34. Other parameters like the steam/biomass (s/B) ratio and catalyst also played a critical role in tar reduction. This paper demonstrates the conversion of some tar components and elucidates their chemical properties during gasification.

关键词： gasification tar components operating parameters

An Inequality for the Perron Pair of an Irreducible and symmetric Nonnegative Tensor with Application

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Journal of the Operations Research society of China 2017年第1期5卷 65-82页

作者： Mao-Lin che Yi-Min Wei school of Mathematical sciences Fudan UniversityShanghai 200433China school of Mathematical sciences and shanghai Key Laboratory of Contemporary Applied Mathematics Fudan UniversityShanghai 200433China

The main purpose of this paper is to consider the Perron pair of an irreducible and symmetric nonnegative tensor and the smallest eigenvalue of an irreducible and symmetric nonsingular *** analyze the analytical property of an algebraic simple eigenvalue of symmetric *** also derive an inequality about the Perron pair of nonnegative tensors based on plane stochastic *** finally consider the perturbation of the smallest eigenvalue of nonsingular M-tensors and design a strategy to compute its smallest *** verify our results via random numerical examples.

关键词： Nonnegative tensor symmetric tensor Irreducible tensor M-Tensor H-Eigenpair An algebraic simple eigenvalue The Perron pair The smallest eigenvalue Perturbation

Nucleoside modified mRNA-lipid nanoparticles as a new delivery platform for the repair of the injured spinal cord

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Neural Regeneration Research 2025年第8期20卷 2311-2312页

作者： Krisztián Pajer Tamás Bellák Antal Nógrádi Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary

spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular *** the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(Khyeam et al.,2021).

关键词： injured capacity modified