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KFDA and clustering based multiclass SVM for intrusion detection

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 123-128页

作者： WEI Yu-xin WU mu-qing Institute of Communication Networks Intergrated Technique Beijing University of Posts and Telecommunications Beijing 100876 China

To improve the classification accuracy and reduce the training time, an intrusion detection technology is proposed, which combines feature extraction technology and multiclass support vector machine （SVM） classification algorithm. The intrusion detection model setup has two phases. The first phase is to project the original training data into kernel fisher discriminant analysis （KFDA） space. The second phase is to use fuzzy clustering technology to cluster the projected data and construct the decision tree, based on the clustering results. The overall detection model is set up based on the decision tree. Results of the experiment using knowledge discovery and data mining （KDD） from 99 datasets demonstrate that the proposed technology can be an an effective way for intrusion detection.

关键词： intrusion detection kernel fisher discriminant analysis fuzzy clustering support vector machine

Modelling method with missing values based on clustering and support vector regression

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Journal of Systems Engineering and Electronics 2010年第1期21卷 142-147页

作者： Ling Wang Dongmei Fu qing Li Zhichun mu Information Engineering School University of Science and Technology Beijing Beijing 100083 R R. China

Most real application processes belong to a complex nonlinear system with incomplete information. It is difficult to estimate a model by assuming that the data set is governed by a global model. Moreover, in real processes, the available data set is usually obtained with missing values. To overcome the shortcomings of global modeling and missing data values, a new modeling method is proposed. Firstly, an incomplete data set with missing values is partitioned into several clusters by a K-means with soft constraints （KSC） algorithm, which incorporates soft constraints to enable clustering with missing values. Then a local model based on each group is developed by using SVR algorithm, which adopts a missing value insensitive （MVI） kernel to investigate the missing value estimation problem. For each local model, its valid area is gotten as well. Simulation results prove the effectiveness of the current local model and the estimation algorithm.

关键词： modeling missing value K-means with soft constraints clustering missing value insensitive kernel.

Seismic attenuation relationship with homogeneous and heterogeneous prediction-error variance models

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 1-11页

作者： He-qing mu Rong-Rong Xu Ka-Veng Yuen Faculty of Science and Technology University of Macao

Peak ground acceleration(PGA) estimation is an important task in earthquake engineering *** of the most well-known models is the Boore-Joyner-Fumal formula,which estimates the PGA using the moment magnitude,the site-to-fault distance and the site foundation *** the present study,the complexity for this formula and the homogeneity assumption for the prediction-error variance are investigated and an effi ciency-robustness balanced formula is *** this purpose,a reduced-order Monte Carlo simulation algorithm for Bayesian model class selection is presented to obtain the most suitable predictive formula and prediction-error model for the seismic attenuation *** this approach,each model class(a predictive formula with a prediction-error model) is evaluated according to its plausibility given the *** one with the highest plausibility is robust since it possesses the optimal balance between the data fi tting capability and the sensitivity to noise.A database of strong ground motion records in the Tangshan region of China is obtained from the China Earthquake Data Center for the *** optimal predictive formula is proposed based on this *** is shown that the proposed formula with heterogeneous prediction-error variance is much simpler than the attenuation model suggested by Boore,Joyner and Fumal(1993).

关键词： Bayesian inference Boore-Joyner-Fumal formula heterogeneity variance input-dependent variance model class selection peak ground acceleration seismic attenuation

Efficient Mesh Updating Scheme for the ALE Corotational Formulation of an Arbitrarily Curved Beam

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Acta Mechanica Solida Sinica 2023年第5期36卷 647-657页

作者： Lanfeng Deng mu-qing Niu Yimin Fan Li-Qun Chen Department of Mechanics School of ScienceHarbin Institute of TechnologyShenzhen 518055China

This paper presents an efficient mesh updating scheme(muS)for the arbitrary Lagrangian-Eulerian(ALE)formulation of an arbitrarily curved beam based on the corotational *** discretizing the beam using both Lagrangian elements and ALE elements,the proposed muS can take full advantage of the simple expression form of the Lagrangian formulation and the accurate moving-load description of the ALE *** deleting-node and adding-node procedures of the muS can avoid the negative influence of the variation of the ALE element length on the element accuracy and stiffness matrix *** contrast to the adding-node procedure for Lagrangian elements,interpolation cannot be used *** a Lagrangian node in an ALE element is investigated,and the displacement,velocity,and acceleration of the newly added node are evaluated accurately based on the corotational *** examples are investigated to verify the validity,computational accuracy and computational efficiency of the proposed muS by comparing the results of the muS with those from literature that utilized traditional ALE *** examples show that the proposed muS has significant advantages in terms of computational time and computer memory.

关键词： Corotational method Arbitrary Lagrangian–Eulerian formulation Geometric nonlinearity Moving loads Flexible beams

Reliable routing mechanism based on neighbor stability for MANET

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维普期刊数据库

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 33-39页

作者： WU Da-peng WU mu-qing ZHEN Yan Broadband Communication Networks Lab Beijing University of Posts and Telecommunications Beijing 100876 China

One critical issue for routing in mobile Ad-hoc networks （MANETs） is how to select a reliable path that can last longer because mobility may cause frequent breakdown in radio links. A novel routing mechanism based on link lifetime estimation is proposed in this article. In this mechanism, the node＇s received signal strength is obtained continuously by using Newton interpolation polynomial, and by method of middle value and interception, the reference points are selected to estimate the link lifetime. With the constraint of link lifetime and hop counts, the source nodes set up the route hop by hop. The simulations show that link lifetime can be predicted regardless of mobility pattern. Moreover, the route discovery times and packet drop ratio can be reduced by the proposed mechanism, and thus improving the performance of MANETs.

关键词： Ad-hoc networks routing protocol link lifetime received signal strength interpolation polynomial

Controlling the entanglement of mechanical oscillators in composite optomechanical system

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Chinese Physics B 2018年第4期27卷 178-183页

作者： Jun Zhang qing-Xia mu Wen-Zhao Zhang School of Mathematics and Statistics Guizhou University of Finance and Economics Guiyang 550025 China Mathematics and Physics Department North China Electric Power University Beijing 102206 China Beijing Computational Science Research Center (CSRC) Beijing 100193 China

A controllable entanglement scheme of two mechanical oscillators is proposed in a composite optomechanical *** the case of strong driving and high dissipation,the dynamics of the movable mirror of the optomechanical cavity is characterized by an effective frequency in the long-time evolution of the *** the classical nonlinear effects in an optomechanical system,we investigate the relationship between the effective frequency of the movable mirror and the adjustable parameters of the *** shows that the effective frequency of the movable mirror can be adjusted ranging fromωm（the resonance frequency of the coupling oscillator） to-ω*** the condition of experimental realization,we can generate and control steady-state entanglement between two oscillators by adjusting the effective frequency of the movable mirror and reducing the effective dissipation by selecting the parameter of the cavity driving laser *** scheme provides a promising platform to control the steady-state behavior of solid-state qubits using classical manipulation,which is significant for quantum information processing and fundamental research.

关键词： entanglement optomechanics

Double-passage mechanical cooling in a coupled optomechanical system

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Chinese Physics B 2019年第11期28卷 173-178页

作者： qing-Xia mu Chao Lang Wen-Zhao Zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Beijing Computational Science Research Center(CSRC) Beijing 100193China

We consider a three-mode optomechanical system where two cavity modes are coupled to a common mechanical oscillator. We focus on the resolved sideband limit and illustrate the relation between the significant parameters of the system and the instantaneous-state mean phonon number of the oscillator cooled to the ground state, particularly at the early stage of the evolution. It is worth noting that the optical coupling sets up a correlation between the two cavity modes,which has significant effect on the cooling process. Using numerical solutions, we find that the inter-cavity coupling will decrease the cooling effect when both cavities have the same effective optomechanical coupling. However, when the effective optomechanical couplings are different, the cooling effect will be strongly improved by selecting appropriate range of inter-cavity coupling.

关键词： optomechanical system ground-state cooling quantum optics

Effects of solar radiation and fine roots on suction of Amorpha fruticose-vegetated soil

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Journal of Mountain Science 2023年第6期20卷 1790-1804页

作者： GUO Han-qing CHEN Xiao-qing SONG Dong-ri mu qing-yi SADEGHI Hamed JIANG Hao LV Ming Laboratory of Mountain Hazards and Earth Surface Process/Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China University of Chinese Academy of Sciences Beijing 100049China Department of Civil Engineering Xi'an Jiaotong UniversityXi'an 710049China Department of Civil Engineering Sharif University of TechnologyTehran ***Iran

The thickness of shallow landslides is generally less than 2 m,which is of the same order of magnitude as the growth range of vegetation *** roots can improve the stability of shallow soil through mechanical and hydraulic ***,the landslide process is closely related to the plant roots growing on the slope *** roots play a dominant role in the regulation of soil suction through solar radiation induced ***,little is known about the correlation between cumulative solar radiation and soil ***,the specific effects of fine roots on the suction distribution are not clear in most previous *** this study,a vegetated soil of a drought-tolerant and water-tolerant shrub,namely Amorpha fruticose,was *** suction and volumetric water content of bare and vegetated soils were monitored under natural conditions for 4 *** results demonstrate that there is a nearly linear relationship between cumulative solar radiation and suction ranging from zero to 100 *** the modeling of the soil-plant-atmosphere interactions,this relationship could serve a significant role in calculating the root water uptake under given solar radiation *** addition,higher suctions were observed at the lower layer of the vegetated soil than those at the middle layer,which is different from the results of vegetated soil from previous *** is due to the fact that the root area index(RAI)of fine roots at the lower layer is twice that of the middle ***,the higher concentration of fine roots at the lower layer of vegetated soil sample resembles the root distribution of shrub near the soil-bedrock interface on shallow bedrock *** fine roots would increase soil suction through transpiration,and hence reduce the permeability and increase shear strength of ***,these new findings serve as a preliminary step on the evaluation of the stability of this common ty

关键词： Field monitoring Fine roots Solar radiation Suction Shallow bedrock landslide

Layered coordination polymer with two-dimensional covalent bismuth-organic networks:Semiconductor and lithium ion storage

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Nano Research 2024年第3期17卷 2181-2185页

作者： mu-qing Li Yulin Cao Lei Qin Hua Cheng Weimin Yang Zhouguang Lu School of Materials Science and Environmental Engineering Shenzhen Polytechnic UniversityShenzhen 518055China Industrial Training Center Shenzhen Polytechnic UniversityShenzhen 518055China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

Single crystals of a bismuth-based coordination polymer(CP)with carboxyl-thiol ligands,[Bi(C_(8)H_(2)O_(4)S_(2))(C2H8N)]n(Bi-DSBDC-DMA,DMBDC=2,5-disulfur-1,4-dicarboxylate,DMA=dimethylamine),have been successfully synthesized.X-ray diffraction analysis reveals that Bi-DSBDC-DMA possesses a layered structure,with two-dimensional(2D)Bi-DSBDC networks alternating with layers composed of dimethylamine *** material demonstrates semiconducting properties,featuring an optical bandgap of 2.2 eV and an electrical conductivity of 2×10^(-8) S/***,electrodes based on this material exhibit a capacity of 250 mAh/g after 200 cycles for lithium-ion storage.

关键词： bismuth layer coordination polymer(CP) semiconductor lithium ion storage