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A calculation method for a power user's CIC under specific conditions in smart distribution grid

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Science China(Technological Sciences) 2015年第7期58卷 1162-1172页

作者： SUN bing YU YiXin Key Laboratory of Smart Grid of Ministry of Education Tianjin University

This paper presents a practical method for calculating a power user’s customer interruption costs(CIC)under specific *** novel method has been developed,based on the CIC results predicted by Lawrence Berkeley National Laboratory(LBNL),so that the key factors,such as customer type,customer size,interruption occurrence time and interruption duration can be *** compared to the LBNL method,the method proposed here is easy to understand and easy to execute with an acceptable *** lays a solid foundation for further investigation of distributed generators and demand response in assessing reliability value of smart distribution grid(SDG).The effectiveness of the proposed method is confirmed through the assessment of RBTS-Bus2.

关键词： smart distribution grid reliability value customer interruption costs customer type customer size interruption oc-currence time interruption duration

Damage localization effects of the regeneratively-cooled thrust chamber wall in LOX/methane rocket engines

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Chinese Journal of Aeronautics 2018年第8期31卷 1667-1678页

作者： Jiawen SONG bing SUN School of Astronautics Beihang University

To investigate the damage localization effects of the thrust chamber wall caused by combustions in LOX/methane rocket engines, a fluid-structural coupling computational methodology with a multi-channel model is developed to obtain 3-demensioanl thermal and structural *** and mechanical loads are calculated by a validated finite volume fluid-thermal coupling numerical method considering non-premixed combustion processes of propellants. The methodology is subsequently performed on an LOX/methane thrust chamber under cyclic operation. Results show that the heat loads of the thrust chamber wall are apparently non-uniform in the circumferential direction. There are noticeable disparities between different cooling channels in terms of temperature and strain distributions at the end of the hot run phase, which in turn leads to different temperature ranges, strain ranges, and residual strains during one cycle. With the work cycle proceeding, the circumferential localization effect of the residual strain would be significantly enhanced. A post-processing damage analysis reveals that the low-cycle fatigue damage accumulated in each cycle is almost unchanged, while the quasi static damage accumulated in a considered cycle declines until stabilized after several cycles. The maximum discrepancy of the predicted lives between different cooling channels is about 30%.

关键词： Cyclic plasticity Damage Heat transfer Regenerative cooling Rocket engine Service life Thrust chamber

Dynamic clustering of distributed source coding in wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2009年第1期16卷 22-26页

作者： LIU bing Information Security Department Beijing Electronic Science and Technology Institute Beijing 100070 China

There are correlations of data in adjacent sensor nodes in wireless sensor networks （WSNs）. Distributed source coamg （DSC） is an idea to improve the energy efficiency in WSNs by compressing the sensor data with correlations to others, When utilizing the DSC, the network architecture that, deciding which nodes to transmit the side information and which nodes to compress according to the correlations, influences the compression efficiency significantly. Comparing with former schemes that have no adaptations, a dynamic clustering scheme is presented in this article, with which the network is partitioned to clusters adaptive to the topology and the degree of correlations. The simulation indicates that the proposed scheme has higher efficiency than static clustering schemes.

关键词： WSNs DSC clustering

On Least Squares Weighted Recursive Estimation of Clock Skew and Offset in Wireless Sensor Networks

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Chinese Journal of Electronics 2017年第5期26卷 1041-1047页

作者： HU bing SUN Zhixin Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and Telecommunications

Three clock synchronization algorithms for Wireless sensor networks(WSNs) in Pairwise broadcast synchronization(PBS) mechanism are *** include the joint Least squares estimator(LS),joint Least squares weighted estimator(LSW) and joint Least squares weighted Recursive estimator(R-LSW).For these estimators,the corresponding algorithms are derived and described by assuming a Gaussian random delay *** PBS,these estimators can achieve the Cramer-Rao lower bound(CRLB) for both listening node and active node without knowledge of the deterministic *** purpose of considering R-LSW is to reduce the use of storage space with the method of estimating while *** and analytical results verify that the estimators are efficient.

关键词： Clock synchronization Wireless sensor networks(WSNs) Pairwise broadcast synchronization(PBS) Least squares estimator(LS)

Novel TPN control algorithm for exoatmospheric intercept

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1290-1295页

作者： Chen Lei Zhang bing Coll. of Aerospace and Material Engineering National Univ. of Defense Technology Changsha 410073 P. R. China

A novel control algorithm with fixed pulse thrust, based on true proportional navigation（TPN）, is proposed for exoatmospheric *** to the TPN guidance law and pulse thrust characteristics, the principle of control command is presented, the control stability and precision are *** the help of the TPN guidance law, the algorithm can automatically modulate the turn-on time and duration of the thrust, which could effectively limit the impact of measure noise of the line-of-sight（LOS） angle and rate on the interception *** last, the number-theoretic method（NTM） is introduced to acquire the relation between control algorithm and miss-distance, even as it simulates the intercept process with initial state *** the reliability of the algorithm is demonstrated with the simulation result.

关键词： exoatmospheric intercept true proportional navigation pulse thrust control algorithm numbertheoretic method.

Study on fluid-structure interaction in liquid oxygen feeding pipe systems using finite volume method

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Acta Mechanica Sinica 2011年第5期27卷 706-712页

作者： Xin Wei bing Sun Institute of Telecommunication Satellite China Academy of Space Technology100194 Beijing China School of Astronautics Beihang University 100191 Beijing China

The fluid-structure interaction may occur in space launch vehicles,which would lead to bad performance of vehicles,damage equipments on vehicles,or even affect astronauts＇ *** this paper,analysis on dynamic behavior of liquid oxygen （LOX） feeding pipe system in a large scale launch vehicle is performed,with the effect of fluid-structure interaction （FSI） taken into *** pipe system is simplified as a planar FSI model with Poisson coupling and junction *** tests on pipes between the tank and the pump are solved by the finite volume *** show that restrictions weaken the interaction between axial and lateral *** reasonable results regarding frequencies and modes indicate that the FSI affects substantially the dynamic analysis,and thus highlight the usefulness of the proposed *** study would provide a reference to the pipe test,as well as facilitate further studies on oscillation suppression.

关键词： Fluid-structure interaction · Liquid oxygen · Finite volume method

Coherent state transfer through a multi-channel quantum network： Natural versus controlled evolution passage

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Science China(Physics,Mechanics & Astronomy) 2016年第4期59卷 13-18页

作者： bing Chen Yong Li College of Electronics Communication and Physics Shandong University of Science and Technology Qingdao 266510 China Beijing Computational Science Research Center Beijing 100084 China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China

Quantum state transfer(QST) is an important task in quantum information processing. In this study, we describe two approaches for the high-fidelity transfer of a quantum state between two opposite quantum dots attached to a multi-channel quantum ***, we demonstrate that a high-efficiency QST can be achieved with the coherent time evolution of a quantum system without any external control. Second, we present an approach that uses an alternative mechanism for a high-fidelity QST. By adiabatically varying tunnel couplings, it is possible to implement the complete transmission of a quantum state based on this quantum mechanical mechanism.

关键词： tight-binding model quantum state transfer adiabatic passage

Bloom-Gilman Duality of Nucleon Spin Structure Function and Elastic Peak Contribution

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Communications in Theoretical Physics 2005年第4期43卷 695-698页

作者： DONGYu-bing InstituteofHighEnergyPhysics theChineseAcademyofSciencesBejing100039China

By employing the parametrization form of the nucleon spin structure functionin the resonance region, which includes the contributions of the resonance peaks and of nonresonancebackground, we study Bloom—Oilman quark-... 详细信息

关键词： Bloom-Gilman quark-hadron duality nucleon spin structure functions parametrization

Acceleration of DDT by non-thermal plasma in a single-trial detonation tube

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Chinese Journal of Aeronautics 2018年第5期31卷 1012-1019页

作者： Dianfeng ZHENG bing WANG College of Engineering Peking University School of Aerospace Engineering Tsinghua University

This paper compares the flame acceleration in single-trial dual-detonation tubes triggered by a spark plug and non-thermal plasma igniter. The low-temperature plasma was generated by an in-house novel AC-driven dielectric barrier discharge igniter, which reduces the power supply requirements and was applied in the quiescent ignition of a single-trial detonation tube. Three different types of detonation mixtures were tested with flame propagation tracked by ion probes and pressure waves recorded by high-frequency pressure transducers. The flame propagation speeds were calculated and compared based on signals from the ion probes. The detonation combustion succeeded in the dual tubes, but the deflagration-to-detonation transition could be significantly accelerated by the plasma for all mixtures, as it was shortened by more than 50% compared to that of the spark plug. The present study provides a suitable technological approach for igniters of PDEs.

关键词： AC driven Deflagration-to-detonation transition Dielectric barrier discharge Non-thermal plasma Pulse detonation engine