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science China(Information sciences) 2024年第5期67卷 329-330页

作者： Lixiao ZHOU Changbing tang Zheng BAO Yang LIU Xinghuo YU College of Physics and electronics Information engineering Zhejiang Normal University school of computer science and Technology Zhejiang Normal University school of Mathematical sciences Zhejiang Normal University school of engineering RMIT University

Climate change is a global issue that necessitates collective responsibility from all nations. Recently, a blockchainenabled emission trading scheme(ETS) has been proposed for reducing carbon emissions to overcome the drawbacks of centralized methods [1, 2]. However, existing consensus protocols in blockchain have not been well prepared for low energy consumption and high incentive compatibility [3],which is contrary to the low carbon goal of ETS.

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Quorum-Based Energy Conserving Mechanism in Wireless Mesh Networks

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ZTE Communications 2008年第2期 34-38页

作者： Liu Tianxi, tang Xiaotong, Jiao Bingli (school of electronics engineering and computer science, Peking University, Beijing 100871, China)

Energy conservation is an important issue for wireless Mesh network. The Quorum energy conserving mechanism, discussed in this article, is quite suitable to wireless Mesh networks because it is insensitive to network scale, host density, mobility and multi-hop. Originally designed for the Mobile Ad hoc Network (MANET) environment, the Quorum mechanism can work in two modes: synchronous and asynchronous, according to the difficulty of clock synchronization. Currently, the research on Quorum energy conserving systems focuses on energy efficiency optimization and adaptive system. As for other issues, such as the collaboration between synchronous and asynchronous working modes, and the cross-layer design for integrating Quorum mechanism-based energy conservation with power control and MAC routing, there is much research to do.

关键词： Mesh work Quorum-Based Energy Conserving Mechanism in Wireless Mesh Networks MANETs WMNs IEEE

A new simulated annealing method of designing NMR biplanar shim coils

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Progress in Natural science:Materials International 2006年第7期16卷 747-752页

作者： QI Feng, tang Xin, WANG Weimin, SHEN Yifei, LIU Shaopo and JIANG Zhongde ( Key Laboratory for Quantum Information and Measurements of Ministry of Education, school of electronics engineering & computer science, Peking University, Beijing 100871, China Institute of Heavy Ion Physics, and Beijing Key Laboratory of Medical Physics and engineering, Physical school, Peking University, Beijing 100871, China) Peking Univ Sch Elect Engn & Comp Sci Minist Educ Key Lab Quantum Informat & Measurements Beijing 100871 Peoples R China Peking Univ Sch Phys Beijing Key Lab Med Phys & Engn Beijing 100871 Peoples R China Peking Univ Inst Heavy Ion Phys Beijing 100871 Peoples R China

A new SA (simulated annealing) method is presented for the design of longitudinal shim coils for NMR (nuclear magnetic resonance) equipment. First, AGL (adaptive Gauss-Lobatto) quadrature used by the traditional SA method is analyzed. Two kinds of complete elliptic integrals are introduced to integrate the spatial magnetic field, which increases the computing speed by 13. 3 times. Then, the system energy calculation is extended to the field of the z-axis. The results illustrate that the coil-set efficiency designed by the new SA method is 15 % higher than that of the traditional one, and the field inhomogeneity is reduced from 1.20 % to 0.49 % . Finally, a prototype of coil assembly for NMR rock-core analyzer is built, and the experimental results are in good agreement with the theoretically calculated results.

关键词： NMR shim coil design simulated-annealing method complete elliptic integral.

Mode Competition of Low Voltage Backward Wave Oscillator near 500 GHz with Parallel Multi-Beam

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Chinese Journal of electronics 2024年第2期33卷 488-495页

作者： Xiaoyan ZHAO Jincheng HU Haoran ZHANG Sidou GUO Yuming FENG Lin tang Kaichun ZHANG Diwei LIU THz Center School of Electronic Science and Engineering University of Electronic Science and Technology of China school of computer science Southwest Petroleum University

A backward wave oscillator with parallel multiple beams and multi-pin slow-wave structure(SWS)operating at the frequency above 500 GHz is studied. Both the cold-cavity dispersion characteristics and CST Particle Studio simulation results reveal that there are obvious mode competition problems in this kind of terahertz *** that the structure of the multi-pin SWS is similar to that of two-dimensional photonic crystals, we introduce the defects of photonic crystal with the property of filtering into the SWS to suppress high-order ***, a detailed study of the effect of suppressing higher-order modes is carried out in the process of changing location and arrangement pattern of the point defects. The stable, single-mode operation of the terahertz source is realized. The simulation results show that the ratio of the output peak power of the higher-order modes to that of the fundamental mode is less than 1.9%. Also, the source can provide the output peak power of 44.8 m W at the frequency of 502.2 GHz in the case of low beam voltage of 4.7 kV.

关键词： Low voltage Filtering Simulation Voltage Photonic crystals Machining Pins

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结合项约束的闭合模式挖掘研究

计算机科学 2004年第9期31卷 157-160页

作者：王新宇唐世渭北京大学信息科学中心北京100871

事务数据库中频繁模式的挖掘研究作为关联规则等许多数据挖掘问题的核心工作,已经研完了许多年。然而,频繁模式挖掘算法经常产生大量的模式和规则,不但降低了算法的执行效率,同时也使用户从频繁模式产生有用的规则变得很困难。针对这个... 详细信息

事务数据库中频繁模式的挖掘研究作为关联规则等许多数据挖掘问题的核心工作,已经研完了许多年。然而,频繁模式挖掘算法经常产生大量的模式和规则,不但降低了算法的执行效率,同时也使用户从频繁模式产生有用的规则变得很困难。针对这个问题,最近的研究主要集中于两点,一种方法是允许用户附加约束来引导挖掘的过程,通过把约束条件下推到挖掘的底层来缩小模式搜索的空间,提高性能;另一种方法是仅挖掘闭合模式,只产生大于其超集支持度的频繁模式。两种方式都可以大量缩小结果集合的大小,使结果集合更容易被用户理解和使用。那么,把这两种方式相结合,挖掘满足用户约束的闭合频繁模式,理论上来说应该更为高效,更方便理解和使用。基于以上的考虑,做了一些细致的研究,把用户约束分类,并主要讨论了结合项约束的闭合模式生成问题。

关键词：频繁模式约束模式挖掘挖掘算法事务数据库关联规则用户缩小问题方式

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Study On Clamped-Clamped Beam in-plane Capacitive Resonators

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Study On Clamped-Clamped Beam in-plane Capacitive Resonators

3D Walking Planning Optimization for a Biped Robot Using Genetic Algorithm

2008 International Conference on Optical Instruments and Technology

作者： Yingxia Jin~(a,b),Yaquan tang~a,Xiaomei Yu~(*a) a Institute of Microelectronics,Peking University,Beijing China,100871 b school of electronics engineering and computer science,Beijing Institute of Technology,Beijing China,100081

A clamped-clamped beam(CC beam)in-plane capacitive resonator with 100nm gap has been analyzed and fabricated by silicon micromachining technique in this *** nonlinearity effects in this device and the resonant mode of the main structure are analyzed and the overall system dynamics of motion equation and general solution are given *** simulation results of resonant mode indicate that the structure size of the beam has great influence on the resonant frequency of ***,with the high aspect-ratio combined poly- and single-crystal silicon micromachining technology(HARPSS),100nm gap in-piane capacitive resonator has been fabricated.

关键词： MEMS capacitive resonator clamped-clamped beam resonant mode resonant frequency HARPSS

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3D Walking Planning Optimization for a Biped Robot Using Gen...

2004中国机器人足球比赛暨学术研讨会

作者： tang Zhe Sun Zengqi Zhou Changjiu Dept of computer science and Technology, Tsinghua Univ. Beijing 100084 school of Electrical and electronics engineering Singapore Polytechnic 500 Dover Road, Singapore 139651

The motion of the biped is a 3D motion, some DOFs (Degree Of Freedom) determine the motion the sgittal plane, some the motion in the frontal plane. Because the model of mutual effects of the biped motion between the sagittal and frontal plane can not be obtained. The motion coordination between these two planes poses a challenging issue in the biped walking planning. In this paper, we identify some key parameters that determine the main characteristics of me biped walking. According to biped walking efficiency and stability requirement, Multi-Criteria GA (Genetic Algorithm) is used to search a set of optimal key parameters. Through simulation and real robot experiment, the effectiveness of the method has been approved.

关键词： Biped Robot Genetic Algorithm Gait synthesis Walking Planning.

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社会化管理信息系统建设方案研究

计算机工程与应用 2004年第30期40卷 15-17,38页

作者：张鹏童云海唐世渭杨冬青北京大学信息科学技术学院北京100871

随着信息技术的不断发展和政府管理与服务模式的不断变革,社会化管理信息系统在社会生活中发挥着越来越重要的作用。论文以实际应用项目为基础,提出了一套社会化管理信息系统的建设方案,并对其在技术上和应用中的特点进行了详细的分析。

关键词：电子政务社会化管理系统整合数据共享

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基于实体分类的数据库模式匹配方法

计算机科学 2004年第10期31卷 157-159,F004页

作者：于波唐世渭张鹏童云海北京大学信息科学技术学院北京100871

模式匹配在诸如数据集成、数据仓库、信息共享和计算机网络交换等许多应用领域起到关键作用。目前,自动模式匹配方法也不能解决复杂模式情况下的匹配问题。本文提出一种基于关系模式领域中实体分类的数据库模式匹配方法。该方法通过朴... 详细信息

模式匹配在诸如数据集成、数据仓库、信息共享和计算机网络交换等许多应用领域起到关键作用。目前,自动模式匹配方法也不能解决复杂模式情况下的匹配问题。本文提出一种基于关系模式领域中实体分类的数据库模式匹配方法。该方法通过朴素贝叶斯学习将实体分为不同的类(子模式),然后以同样的类来匹配子模式之间的模式元素。本方法在复杂模式条件下可有效提高匹配效率,减少匹配工作量,节省人力资源。

关键词：数据库模式模式匹配子模式朴素贝叶斯匹配方法关系模式计算机网络实体分类关键作用工作量

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