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A new algorithm for computing the convex hull of a planar point set

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1210-1217页

作者： LIU guang-hui CHEN Chuan-bo College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

When the edges of a convex polygon are traversed along one direction,the interior of the convex polygon is always on the same side of the edges. Based on this characteristic of convex polygons,a new algorithm for computing the convex hull of a simple polygon is proposed in this paper,which is then extended to a new algorithm for computing the convex hull of a planar point set. First,the extreme points of the planar point set are found,and the subsets of point candidate for vertex of the convex hull between extreme points are obtained. Then,the ordered convex hull point sequences between extreme points are constructed separately and concatenated by removing redundant extreme points to get the convex hull. The time complexity of the new planar convex hull algorithm is O(nlogh) ,which is equal to the time complexity of the best output-sensitive planar convex hull algorithms. Compared with the algorithm having the same complexity,the new algorithm is much faster.

关键词： Computational geometry Convex hull Extreme points Ordered convex hull point sequence

Observer-based control for the platform of a tethered space robot

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Chinese Journal of Aeronautics 2018年第8期31卷 1786-1796页

作者： guang ZHAI Heming ZHENG bo ZHANG Aerospace Engineering School Beijing Institute of TechnologyBeijing 100081China Aerospace System Engineering Shanghai Shanghai 201109China

This paper addresses the attitude control problem of a space tethered robot platform in the presence of unknown external disturbance caused by a connecting elastic tether. The tethergenerated unknown disturbance leads to tremendous challenges for attitude control of the *** this work, the perturbed attitude dynamics of the platform are derived with a consideration of the libration of the elastic tether, and then with the purpose of compensating the unknown disturbance, major attention is dedicated to develop a nonlinear disturbance observer based on gyros measurements, after which, an adaptive attitude scheme is proposed by combining the disturbance observer with a sliding mode controller. Finally, benefits from the observer based on an adaptive controller are validated by series of numerical simulations.

关键词： Adaptive control Attitude dynamics Disturbance observerSliding mode controlTethered space robot

Image Encryption Application of Chaotic Sequences Incorporating Quantum Keys

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International Journal of Automation and computing 2020年第1期17卷 123-138页

作者： Bin ge Hai-bo Luo School of Computer Science and Engineering Anhui University of Science and Technology

This paper proposes an image encryption algorithm LQBPNN（logistic quantum and back propagation neural network）based on chaotic sequences incorporating quantum keys. Firstly, the improved one-dimensional logistic chaotic sequence is used as the basic key sequence. After the quantum key is introduced, the quantum key is incorporated into the chaotic sequence by nonlinear operation. Then the pixel confused process is completed by the neural network. Finally, two sets of different mixed secret key sequences are used to perform two rounds of diffusion encryption on the confusing image. The experimental results show that the randomness and uniformity of the key sequence are effectively enhanced. The algorithm has a secret key space greater than 2182. The adjacent pixel correlation of the encrypted image is close to 0, and the information entropy is close to 8. The ciphertext image can resist several common attacks such as typical attacks, statistical analysis attacks and differential attacks.

关键词： Logistic chaotic system quantum key nonlinear operation sequence performance image encryption algorithm

Current status of percutaneous coronary intervention of chronic total occlusion

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第8期13卷 589-602页

作者： Jun-bo ge Department of Cardiology Zhongshan HospitalFudan UniversityShanghai 200032China

This paper describes the current status of percutaneous coronary intervention (PCI) for totally occluded coronary arteries. Chronic total occlusion is associated with 10%-20% of all PCI procedures. Results show that opening an occluded vessel, especially one supplying a considerable area of myocardium, may be beneficial for a patient's angina relief and heart function. We describe the devices used currently in re-canalization such as new wires, microcatheters (including Tonus and Cosair) and intravascular ultrasound guidance. Different techniques to improve the success rate and reduce complications are discussed in detail.

关键词： Percutaneous coronary intervention Chronic total occlusion Retrograde approach

The Hyers-Ulam Stability of a Functional Equation Deriving from Quadratic and Cubic Functions in Quasi-β-normed Spaces

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Acta Mathematica Sinica,English Series 2010年第12期26卷 2335-2348页

作者： Li guang WANG bo LIU School of Mathematical Sciences Qufu Normal University Qufu 273165 P. R. China

In this paper, we investigate the Hyers-Ulam stability of the following function equation 2f（2x ＋ y）＋ 2f（2x - y） = 4f（x ＋ y）＋ 4f（x - y）＋ 4f（2x）＋ f（2y） - Sf（x） - 8f（y） in quasi-β-normed spaces.

关键词： Hyers-Ulam stability quadratic mapping cubic mapping quasi-β-normed spaces (β,p)-Banach spaces

含跟网/构网型混联多馈入系统协调优化配置方法

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中国电机工程学报 2025年第2期45卷 588-600,I0016页

作者：余光正胡越刘晨曦汤波辛焕海马骏超崔葛安上海电力大学电气工程学院上海市杨浦区200090 浙江大学电气工程学院浙江省杭州市310027 国网浙江省电力科学研究院浙江省杭州市310014 国网陕西省电力有限公司电力调度控制中心陕西省西安市710000

随着传统同步机组被电力电子设备逐步取代,电力系统由原来的“物理同步”逐渐转变为“控制同步”。因此,由变流器控制环节引发的稳定问题受到广泛关注。已有研究表明,含跟网/构网型设备的混联多馈入系统中构网型设备能够抑制弱电网下由... 详细信息

随着传统同步机组被电力电子设备逐步取代,电力系统由原来的“物理同步”逐渐转变为“控制同步”。因此,由变流器控制环节引发的稳定问题受到广泛关注。已有研究表明,含跟网/构网型设备的混联多馈入系统中构网型设备能够抑制弱电网下由跟网型设备并网引起的次同步振荡,然而其在强电网下容易导致系统出现低频振荡现象。而目前电力系统仍处于向“双高”系统转变的过渡阶段,关于不同电网强度下混联多馈入系统中跟网/构网型变流器对电网电压支撑能力的量化评估及其在多频段下的协调优化配置方法仍不清晰。为此,该文首先对单馈入跟网/构网型变流器并网系统进行模态分析,探究不同电网强度下跟网/构网型变流器对应的主导振荡模态在多频段下的分布特性,并形成混联多馈入系统的协调优化配置原则。其次,基于模态解耦的思想对混联多馈入系统的稳定性进行等效近似,揭示多频段下系统主导振荡模态阻尼比与跟网/构网型支撑能力量化指标之间的关系。由此,提出一种面向系统小干扰稳定性提升的跟网/构网型协调优化配置方法。最后,通过仿真算例验证所提混联多馈入系统等效近似方法的正确性和协调优化配置方法的有效性。

关键词：跟网/构网型设备混联多馈入系统模态解耦电网电压支撑能力协调优化配置

Deep understanding of the interaction between thienorphine and UDP-glucuronosyltransferase(UGT) isoforms

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Deep understanding of the interaction between thienorphine a...

Arc-Transitive Graphs of Square-free Order with Valency 11

第十三次全国临床药理学学术大会

作者： DONG Rui-hua~1,ge guang-bo~2,ZHU Liang-liang~2,GAO Xin~1,WU Yuan~1,YANG Ling~2,LIU Ze-yuan~1 1.Department of Clinical Pharmacology,Affiliated Hospital,Academy of Military Medical Sciences.Beijing 100071 2.Laboratory of Pharmaceutical Resource Discovery,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian,116023

*** has been demonstrated to be a potent,long-acting partial opioid *** is being developed as a good candidate to treat opioid dependence. *** thienorphine’s glucuronide was detected after thienorphine was incubated with human liver microsomes (HLMs).Recombinant UGT isoforms screening experiment and enzyme kinetic study showed that UGT1A1 completely contributed to the glucuronidation of thienorphine. *** the tested UGT isoforms,UGT1A3 and UGT2B7 were inhibited by thienorphine,with other UGT isoforms negligibly *** inhibition type is competitive,and inhibition kinetic parameters(Ki) were 1.65 and 5.27μM for UGT1A3 and UGT2B7,***,due to low plasma concentration of thienorphine,in vivo drug-drug interaction might not occur.

关键词： Thienorphine UDP-glucuronosyltransferase(UGT) drug-drug interaction

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Algebra Colloquium 2021年第4期28卷 645-654页

作者： guang Li bo Ling Zaiping Lu School of Mathematics and Statistics Shandong University of Technology ZiboShandong 255049China School of Mathematics and Computer Science Yunnan Minzu University Kunming 650000China Center for Combinatorics LPMCNankai UniversityTianjin 300071China

In this paper,we present a complete list of connected arc-transitive graphs of square-free order with valency *** list includes the complete bipartite graph K11,11,the normal Cayley graphs of dihedral groups and the g... 详细信息

关键词： arc-transitive graph coset graph normal quotient vertex-stabilizer (almost)simple group

Modeling resistance index of taxoids to MCF-7 cell lines using ANN together with electrotopological state descriptors

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Modeling resistance index of taxoids to MCF-7 cell lines usi...