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Knowledge Map Mining of Financial Data

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Tsinghua Science and Technology 2013年第1期18卷 68-76页

作者： Wenhui Shou Wenhui Fan boyuan liu Yuyang Lai the Department of Automation Tsinghua University the SOYOTEC Technologies Co. Ltd.

The Knowledge Map （KM） concept, which was derived to describe and manage knowledge. KM provides insight into the from the Fuzzy Cognitive Map （FCM）, is used interdependencies and uncertainties contained in the system. This paper uses a model-free method to mine KMs in historical data to analyze component stock corporations of the Shanghai Stock 50 index. The analyses use static and time-domain analyses. The results indicate that a knowledge map is useful for representing knowledge and for monitoring the health of companies. Furthermore, sudden changes of the key features of the KMs should be taken seriously by policymakers as an alarm of a crisis.

关键词： Knowledge Map (KM) data mining health monitoring crisis warning

A transceiver frequency conversion module based on 3D micropackaging technology

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Journal of Systems Engineering and Electronics 2020年第5期31卷 899-907页

作者： liu boyuan WANG Qingping WU Weiwei YUAN Naichang School of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073China

The idea of Ku-band transceiver frequency conversion module design based on 3D micropackaging technology is proposed. By using the double frequency conversion technology,the dual transceiver circuit from Ku-band to L-band is realized by combining with the local oscillator and the power control circuit to complete functions such as amplification, filtering and gain. In order to achieve the performance optimization and a high level of integration of the Ku-band monolithic microwave integrated circuits(MMIC) operating chip, the 3 D vertical interconnection micro-assembly technology is used. By stacking solder balls on the printed circuit board(PCB), the technology decreases the volume of the original transceiver to a miniaturized module. The module has a good electromagnetic compatibility through special structure designs. This module has the characteristics of miniaturization, low power consumption and high density, which is suitable for popularization in practical application.

关键词： Ku-band frequency conversion 3D packaging chip electromagnetic compatibility

Weak Internal Partition of Regular Graphs

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Communications in Mathematics and Statistics 2017年第3期5卷 335-338页

作者： Xinkai Tao boyuan liu Xinmin Hou Key Laboratory of Wu Wen-Tsun Mathematics Chinese Academy of SciencesSchool of Mathematical SciencesUniversity of Science and Technology of ChinaHefeiAnhui 230026China

An(s,t)-partition of a graph G=(V,E)is a partition of V=V 1∪V 2 suchthatδ(G[V_(1)])≥s andδ(G[V_(2)])≥***,forsufficiently large n,every d-regular graph of order n has a(d/2,d/2)-partition(called an internal partition).Inthispaper,weprovethateveryd-regulargraphofordern hasa(d/2,d/2)partition(called a weak internal partition)for d≤9 and sufficiently large n.

关键词： Internal partition External partition Regular graph

Data Driven Uncertainty Evaluation for Complex Engineered System Design

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维普期刊数据库

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 889-900页

作者： liu boyuan HUANG Shuangxi FAN Wenhui XIAO Tianyuan James HUMANN LAI Yuyang JIN Yan State CIMS Engineering Research Center Tsinghua University Beijing 100084 China University of Southern California Los Angeles California USA SOYOTEC Technologies Co. Ltd. Beijing 100081 China

Complex engineered systems are often difficult to analyze and design due to the tangled interdependencies among their subsystems and components. Conventional design methods often need exact modeling or accurate structure decomposition, which limits their practical application. The rapid expansion of data makes utilizing data to guide and improve system design indispensable in practical engineering. In this paper, a data driven uncertainty evaluation approach is proposed to support the design of complex engineered systems. The core of the approach is a data-mining based uncertainty evaluation method that predicts the uncertainty level of a specific system design by means of analyzing association relations along different system attributes and synthesizing the information entropy of the covered attribute areas, and a quantitative measure of system uncertainty can be obtained accordingly. Monte Carlo simulation is introduced to get the uncertainty extrema, and the possible data distributions under different situations is discussed in detail The uncertainty values can be normalized using the simulation results and the values can be used to evaluate different system designs. A prototype system is established, and two case studies have been carded out. The case of an inverted pendulum system validates the effectiveness of the proposed method, and the case of an oil sump design shows the practicability when two or more design plans need to be compared. This research can be used to evaluate the uncertainty of complex engineered systems completely relying on data, and is ideally suited for plan selection and performance analysis in system design.

关键词： complex engineered system design uncertainty data-driven evaluation Monte Carlo simulation

Neuromorphic metasurface

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Photonics Research 2020年第1期8卷 46-50页

作者： ZHICHENG WU MING ZHOU ERFAN KHORAM boyuan liu ZONGFU YU Department of Electrical and Computer Engineering University of WisconsinMadisonWisconsin 53706USA

Metasurfaces have been used to realize optical functions such as focusing and beam *** use subwavelength nanostructures to control the local amplitude and phase of *** we show that such control could also enable a new function of artificial neural *** demonstrate that metasurfaces can directly recognize objects by focusing light from an object to different spatial locations that correspond to the class of the object.

关键词： surfaces enable surface

All-optical carrier recovery for self-homodyne detection via injection locked Brillouin laser in whispering-gallery-mode microcavity

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Chinese Optics Letters 2021年第11期19卷 93-97页

作者： boyuan liu Yong Geng Qiang Zhang Xinjie Han Jing Xu Heng Zhou Kun Qiu School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

We demonstrate comprehensive investigation of the injection locking dynamics of a backscattered Brillouin laser in silica whispering-gallery-mode microcavity. Via injection locking, the Brillouin laser acquires highly correlated phase with the seed laser, enabling ultra-narrow bandwidth, high gain, and coherent optical amplification. Also, for the first time,to the best of our knowledge, the injection locked Brillouin laser is utilized to implement all-optical carrier recovery from coherent optical data signals. We show that by using the injection locked Brillouin laser as a local oscillator for self-homodyne detection, high-quality data receiving can be realized, even without traditional electrical compensations for carrier frequency and phase drifts.

关键词： optical microcavity stimulated Brillouin scattering laser injection locking self-homodyne detection

Low-noise amplification of dissipative Kerr soliton microcomb lines via optical injection locking lasers

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Chinese Optics Letters 2021年第12期19卷 26-31页

作者： Qiang Zhang boyuan liu Qin Wen Jinhui Qin Yong Geng Qiang Zhou Guangwei Deng Kun Qiu Heng Zhou Key Laboratory of Optical Fiber Sensing and Communication Networks School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731China Information and Quantum Laboratory Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731China

The dissipative Kerr soliton microcomb provides a promising laser source for wavelength-division multiplexing(WDM)communication systems thanks to its compatibility with chip ***,the soliton microcomb commonly suffers from a low-power level due to the intrinsically limited energy conversion efficiency from the continuous-wave pump laser to ultra-short solitary ***,we exploit laser injection locking to amplify and equalize dissipative Kerr soliton comb lines,superior gain factor larger than 30 dB,and optical-signal-to-noise-ratio(OSNR)as high as 60 dB obtained experimentally,providing a potential pathway to constitute a high-power chip-integrated WDM laser source for optical communications.

关键词： Kerr microcomb optical injection locking coherent optical communications

基于MEMS滤波器芯片的X波段混频通道设计

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电子技术应用 2017年第6期43卷 52-55,59页

作者：刘博源徐军电子科技大学物理电子学院四川成都610054

提出了基于MEMS滤波器芯片进行X波段接收模块小型化设计的方法,构成下变频电路,与本振功分电路、电源控制电路完成放大、滤波和增益控制功能,实现由X波段到L波段中频的小体积、低功耗四路下变频接收通道。利用电路分析与建模仿真,分解... 详细信息

提出了基于MEMS滤波器芯片进行X波段接收模块小型化设计的方法,构成下变频电路,与本振功分电路、电源控制电路完成放大、滤波和增益控制功能,实现由X波段到L波段中频的小体积、低功耗四路下变频接收通道。利用电路分析与建模仿真,分解各部分电路的技术指标。各部分电路中最关键的是下变频电路,即混频放大链路,其中的射频开关滤波器和中频滤波器对通道整体性能至关重要,因此可以采用MEMS滤波器芯片设计来实现。MEMS滤波器芯片在性能、体积方面具有明显优势,用以实现的单路混频通道结构紧凑、功耗低,满足小型化、模块化和集成化的技术趋势与需求,适合在实际应用中推广。

关键词：混频 MEMS滤波器芯片四路下变频接收通道 ADS

基于AS拓扑结构与网络服务分布的AS节点关键度分析

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东南大学学报（自然科学版） 2017年第A1期47卷 59-64页

作者：卢作维刘博元张沛李丹丹北京邮电大学网络技术研究院北京100876 国家计算机网络应急技术处理协调中心北京100029

为了评估AS节点在实际网络中的关键度,有效发现实际网络中的关键AS节点,提出了基于加权有效最短路径定义的介数评估AS节点关键度的方法.首先根据valley-free原则计算有效最短路径,避免了一些在实际网络中无效的路径对衡量关键度的影响.... 详细信息

为了评估AS节点在实际网络中的关键度,有效发现实际网络中的关键AS节点,提出了基于加权有效最短路径定义的介数评估AS节点关键度的方法.首先根据valley-free原则计算有效最短路径,避免了一些在实际网络中无效的路径对衡量关键度的影响.进一步通过DNS测量网络重点服务在自治域内的分布情况,结合节点的网络服务权值衡量节点的实际关键度,克服了单纯从拓扑性质上无法较好地反映实际网络中关键度的问题.实验中根据AS关系数据集构建国内范围的AS拓扑模型,利用该方法对AS节点进行排名,并通过与基于介数和基于有效最短路径定义介数的评估方法的比较,验证了该方法能更好地分辨出节点对于实际网络中流量传输、服务提供的关键度.

关键词： AS拓扑节点关键度网络服务分布介数中心性