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Intelligent data attacks against power systems using incomplete network information: a review

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Journal of Modern Power Systems and Clean Energy 2018年第4期6卷 630-641页

作者： Yufei SONG Xuan LIU Zhiyi LI Mohammad SHAHIDEHPOUR Zuyi LI College of Electrical and Information Engineering Hunan University Electrical and Computer Engineering Department Illinois Institute of Technology

With the integration of information technologies, power system operations are increasingly threatened by cyber-attacks. It has even been revealed that an attacker can inject false data into real-time measurements stealthily without knowing the full configuration(e.g., network topology) of a power system. In this paper, we present a comprehensive review on false data injection attacks which utilize barrier conditions, blind identification techniques and data driven approaches to overcome limitations of incomplete network information. We also point out future research topics for facilitating the detection and prevention of such false data attacks.

关键词： Cyber security false data injection attack Incomplete network information Power system state estimation

CUSUM control charts based on likelihood ratio for preliminary analysis

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Science China Mathematics 2007年第1期50卷 47-62页

作者： Yi DAI Zhao-jun WANG Chang-liang ZOU LPMC and Department of Statistics School of Mathematical SciencesNankai UniversityTianjin 300071China

To detect and estimate a shift in either the mean and the deviation or both for the preliminary analysis, the statistical process control (SPC) tool, the control chart based on the likelihood ratio test (LRT), is the most popular method. Sullivan and woodall pointed out the test statistic lrt(n1, n2) is approximately distributed as x2(2) as the sample size n,n1 and n2 are very large, and the value of n1 = 2,3,..., n - 2 and that of n2 = n - n1. So it is inevitable that n1 or n2 is not large. In this paper the limit distribution of lrt(n1, n2) for fixed n1 or n2 is figured out, and the exactly analytic formulae for evaluating the expectation and the variance of the limit distribution are also obtained. In addition, the properties of the standardized likelihood ratio statistic slr(n1, n) are discussed in this paper. Although slr(n1, n) contains the most important information, slr(i, n)(i≠n1) also contains lots of information. The cumulative sum (CUSUM) control chart can obtain more information in this condition. So we propose two CUSUM control charts based on the likelihood ratio statistics for the preliminary analysis on the individual observations. One focuses on detecting the shifts in location in the historical data and the other is more general in detecting a shift in either the location and the scale or both. Moreover, the simulated results show that the proposed two control charts are, respectively, superior to their competitors not only in the detection of the sustained shifts but also in the detection of some other out-of-control situations considered in this paper.

关键词： preliminary analysis false alarm probability CUSUM chart likelihood ratio test.

SOME NEW CLASSES OF ALMOST PERIODIC FUNCTIONS

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Chinese Annals of Mathematics,Series B 1989年第2期10卷 200-213页

作者： C.J.F.UPTON University of Melbourne Parkville Victoria 3052 Australia

In this paper classes of almost periodic functions are formed whlch lie between those established by W. Stepanoff and by H. Burkill.

关键词： CLASSES everywhere adding proof whenever 妇功 false apply Lebesgue 即夕

STRUCTURAL VARIATIONS OF HOLLOW SPINDLE WRAP SPUN YARNS

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Journal of China Textile University(English Edition) 1991年第3期9卷 1-8页

作者：苗孟河陈瑞琪 Department of Mechanical Engineering

The structure of a hollow spindle wrap spun yarn depends greatly on the steadiness of bindertension and of balloon rotation.The two commonly used binder bobbin forms,the cop type andthe flanged type,both as sources of spinning condition fluctuation,are examined in order to revealtheir effects on the wrap spun yarn structure.false twist is introduced on hollow spindle spinningmachines in order to avoid strand breaks before it is tightly wrapped up.However,an investigationof the false twisti g-wrapping process shows that this inevitably causes irregular yarn tortuosity.

关键词： yarn tension twist hollow spindle spinning machine wrap twist false twist yarn tortuosity

美国《保健物理》(Health Physics)杂志英文摘要(2022年122卷第5期)

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辐射防护 2022年第4期42卷 374-378页

Impact of the Coarse Indoor Non-radioactive Aerosols on the Background Radon Progenies’Compensation of a Continuous Air Monitor Gwena l Hoarau 1,Grégoire Dougniaux 1,Fran ois Gensdarmes 1,Philippe Cassette 2,Gilles Ranchoux 3(1.Institut de Radioprotection et de S retéNucléaire(IRSN),PSN-RES,SCA,Laboratoire de physique et mérologie des aérosols(LPMA),Gif-sur-Yvette,91192.France;2.Commissariatàl'nergie Atomique et aux nergies Alternatives(CEA),LIST,Laboratoire National Henri Becquerel(LNE-LNHB),Saclay,91191,France;3.lecricitéde France(EDF),Direction des Projets Déconstruction-Déchets(DP2D),Lyon,69006,France)Abstract:This paper addresses the problem of false positive alarm when using a continuous air monitor(CAM)in decommissioning sites of nuclear facilities.CAMs are used to measure airborne activity and play an important role in the radiation protection of workers likely to be exposed to radioactive aerosols.Monitors usually sample aerosols on a membrane filter.Radioactive particles sampled are detected through the alpha and beta decays that they emit.These latter ionizing particles are measured online by spectrometry thanks to a Passivated Implanted Planar Silicon detector(PIPS).Alpha and beta decays,in this context,come mainly from the natural radon progeny(218 Po,214 Pb,and so on)and,in the case of radioactive contamination,also from artificial radionuclides such as 239 Pu or 137 Cs.The aim of the CAM is to alert the workers when the artificial airborne activity occurs,always considering the presence of a variable background due to the natural particulate airborne activity.The CAM-specific algorithm considers this background dynamically and continuously,often by using a constant parameter.However,non-radioactive aerosols are also sampled on the membrane filter.These latter make the discrimination more difficult as they lead to the deterioration of the alpha-energy spectrum.In this paper,the effect of coarse non-radioactive aerosols on the CAM response is highlighted with four aerosol size-distributions.The evolu

关键词： latter false consequence

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Sympathy Farming

China Weekly 2023年第9期 41-43页

作者： Zhang Xinyu 不详

From spun sob stories to bait-and-switch schemes,fraud among livestreamers selling farm produce is damaging China's poverty alleviation efforts,and legal experts are calling on streaming agencies,online platforms and local governments to weed it out.Concerns over false advertising amonglivestreamers are on the rise-and they stem from produce sellers in China's countryside.According to a 2022 consumer rights report released in April,false advertising ranked second among the top seven issues raised by surveyed Chinese consumers at 37.82 percent.

关键词： advertising false legal

RELATION BETWEEN STRUCTURE OF PP DRAWN FILAMENT AND TEXTURING EFFECT

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Journal of China Textile University(English Edition) 1991年第1期9卷 48-54页

作者：仲蕾兰戚慰先江建明曹正燕 Department of Chemical-fiber Technology

The relationship between the structure of PP drawn filament and the crimp elasticity of tex-tured yarn is investigated.It is found that orientation,crystallinity,and especially,crystalline formof drawn filament are related to crimp property of textured yarn.Lower crystallinity,moderateorientation and unstable para-crystalline structure are necessary for increasing crimp elasticity.Inaddition,the filament structure and properties before and after texturing are compared.

关键词： polypropylene fibre fibre structure textured yarn orientation supermolecular structure false twist texturing crystallinity crystalline form crimp elasticity

Development of Cueing Algorithm Based on “Closed-Loop” Control for Flight Simulator Motion System

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Wuhan University Journal of Natural Sciences 2019年第5期24卷 376-382页

作者： ZHU Daoyang DUAN Shaoli FANG Da College of Intelligent Manufacturing Wuhan Technical College of Communications

The classical washout algorithm had fixed gains and manually constructed filters, so that it led to poor adaptability. Furthermore, it lost the sustained acceleration cues of high-and mid-frequency in cross-over(tilt-coordination) channel, and the acceleration of cross-over frequency was also limited by angular velocity limiter, so the false cues in flight simulation process were clearly perceived by pilots. The paper studied the characteristics of the classical washout algorithm and flight simulator motion platform, tried to redesign the source of cross-over acceleration channel and translation acceleration channel, and transferred the part of cross-over acceleration that was unsimulated sustained acceleration to translation acceleration channel. Comparisons were mainly made between classical washout algorithm and revised algorithm in a longitudinal/pitch direction. The evaluation was based on the implementation of human vestibular perception system. The results demonstrated that the revised algorithm could significantly reduce the phase lag, and improved the spikes tracking performance. Furthermore, sensory angular velocity and the error of sensory acceleration were strictly controlled within the threshold of human perception system, and the displacement was a little broader than the classical washout algorithm. Therefore, it was proved that the new algorithm could diminish the filters parameters and heighten the self-adaptability for the washout algorithm. In addition, the magnitude of false cues was remarkably reduced during flight simulator, and the workspace utilization of the motion platform was developed by "closed-loop" control system.

关键词： classical washout algorithm human vestibular system "closed-loop" control false cues

Generalized resolution in Boolean operator fuzzy logic

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Chinese Science Bulletin 1995年第24期40卷 2092-2095页

作者：邓安生 Department of Computer Science Jilin University Changchun 130023 China

The generalized resolution method presented in ref. [1] is a generalization of Robinson’s resolution principle in the first-order logic, which can be applied to a set of nonclausal formulae, i.e. a set of generalized clauses. The method can not only avoid the symbolic redundancy generated from the procedure of transforming a formula into a set of clauses, but also keep the natural description of the problem.

关键词： Boolean operator fuzzy logic false level generalized resolution.