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A mixture model Parameters Estimation Algorithm for Inter-Contact Times in Internet of Vehicles

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Computers, Materials & Continua 2021年第11期69卷 2445-2457页

作者： Cheng Gong Xinzhu Yang Wei Huangfu Qinghua Lu School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Beijing Advanced Innovation Center for Materials Genome Engineering School of Computer and Communication EngineeringUniversity of Science and Technology Beijing100083China Shunde Graduate School of University of Science and Technology Beijing Foshan City528300GuangdongChina Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services University of Science and Technology BeijingBeijing100083China Commonwealth Scientific and Industrial Research Organization Canberra2600Australia

Communication opportunities among vehicles are important for data transmission over the Internet of Vehicles(IoV).mixture models are appropriate to describe complex spatial-temporal *** calculating the expectation of hidden variables in vehicle communication,Expectation Maximization(EM)algorithm solves the maximum likelihood estimation of parameters,and then obtains the mixture model of vehicle communication ***,the EM algorithm requires multiple iterations and each iteration needs to process all the *** its computational complexity is high.A parameter estimation algorithm with low computational complexity based on Bin Count(BC)and Differential Evolution(DE)(PEBCDE)is *** overcomes the disadvantages of the EM algorithm in solving mixture models for big *** order to reduce the computational complexity of the mixture models in the IoV,massive data are divided into relatively few time intervals and then *** to these few counted values,the parameters of the mixture model are obtained by using DE *** modeling and analysis of simulation data and instance data,the PEBCDE algorithm is verified and discussed from two aspects,i.e.,accuracy and *** numerical solution of the probability distribution parameters is obtained,which further provides a more detailed statistical model for the distribution of the opportunity interval of the IoV.

关键词： Internet of vehicles opportunistic networks inter-contact times mixture model parameters estimation

Multiphase Oil Simulation Based on mixture model 36

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Multiphase Oil Simulation Based on Mixture Model

Data-driven Operation Risk Assessment of Wind-integrated Power Systems via mixture models and Importance Sampling

第36届中国控制会议

作者： Zou Changjun Yin Yong Jing Qianfeng Marine Dynamic Simulation ＆ Control Lab Dalian Maritime University

ISBN: (纸本)9781538629185

The slip velocity associates the mixture velocity with the phase velocity,establishing vital relationship between the phase and *** are many slip velocity models exist,but the limitation among them is the complexity for real time simulation.A simplified slip velocity model is proposed in this *** of our slip velocity model coupled in the mixture model is conducted with satisfactory results.

关键词： Slip velocity model mixture model Multiphase oil simulation

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Journal of Modern Power Systems and Clean Energy 2020年第3期8卷 437-445页

作者： Osama Aslam Ansari Yuzhong Gong Weijia Liu Chi Yung Chung Department of Electrical and Computer Engineering University of SaskatchewanSaskatoonCanada

The increasing penetration of highly intermittent wind generation could seriously jeopardize the operation reliability of power systems and increase the risk of electricity outages. To this end, this paper proposes a novel data-driven method for operation risk assessment of wind-integrated power systems. Firstly, a new approach is presented to model the uncertainty of wind power in lead time. The proposed approach employs k-means clustering and mixture models(MMs) to construct time-dependent probability distributions of wind *** proposed approach can also capture the complicated statistical features of wind power such as multimodality. Then, a nonsequential Monte Carlo simulation(NSMCS) technique is adopted to evaluate the operation risk indices. To improve the computation performance of NSMCS, a cross-entropy based importance sampling(CE-IS) technique is applied. The CE-IS technique is modified to include the proposed model of wind *** method is validated on a modified IEEE 24-bus reliability test system(RTS) and a modified IEEE 3-area RTS while employing the historical data of wind generation. The simulation results verify the importance of accurate modeling of shortterm uncertainty of wind power for operation risk *** case studies have been performed to analyze the impact of transmission systems on operation risk indices. The computational performance of the framework is also examined.

关键词： Cross entropy mixture model Monte Carlo simulation operation risk power system reliability

Semi-supervised Artificial Immune mixture models Clustering

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Chinese Journal of Electronics 2016年第2期25卷 249-255页

作者： HUANG Wenlong WANG Xiaodan LI Guohong KANG Hongxia Air and Missile Defense College Air Force Engineering University State Key Laboratory of Astronautic Dynamics Xi'an Satellite Control Center

Learning with partly labeled data aims at combining labeled and unlabeled data in order to boost the accuracy of an algorithm. The traditional Expectation maximization(EM) algorithm only produces locally optimal solutions, it is sensitive to initialization, and the number of components of mixture model must be known in advance. We propose a novel semi-supervised clustering algorithm that uses Gaussian mixture models(GMM) as the underlying clustering model. A novel adaptive global search mechanism is introduced into semi-supervised gaussian mixture model-based clustering, where the EM algorithm is incorporated with the ideas of an immune clonal selection technique. The new algorithm overcomes the various problems associated with the traditional EM algorithm. And it can improve the effectiveness in estimating the parameters and determining the optimal number of clusters automatically. The experimental results illustrate the proposed algorithm provides significantly better clustering results, when compared with other methods of incorporating equivalence constraints.

关键词： Semi-supervised clustering mixture model Immune clonal selection Globally optimal solution

Simulation of abrasive flow machining process for 2D and 3D mixture models

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Frontiers of Mechanical Engineering 2015年第4期10卷 424-432页

作者： Rupalika DASH Kalipada MAITY Mechanical Engineering Department National Institute of TechnologyRourkela 769008 India

Improvement of surface finish and material removal has been quite a challenge in a finishing operation such as abrasive flow machining （AFM）. Factors that affect the surface finish and material removal are media viscosity, extrusion pressure, piston velocity, and particle size in abrasive flow machining process. Performing experiments for all the parameters and accurately obtaining an optimized parameter in a short time are difficult to accomplish because the operation requires a precise finish. Computational fluid dynamics （CFD） simulation was employed to accurately determine optimum parameters. In the current work, a 2D model was designed, and the flow analysis, force calculation, and material removal prediction were performed and compared with the available experi- mental data. Another 3D model for a swaging die finishing using AFM was simulated at different viscosities of the media to study the effects on the controlling parameters. A CFD simulation was performed by using commercially available ANSYS FLUENT. Two phases were considered for the flow analysis, and multiphase mixture model was taken into account. The fluid was considered to be a Newtonian fluid and the flow laminar with no wall slip.

关键词： abrasive flow machining (AFM) computational fluid dynamics (CFD) modeling mixture model

mixture models for Web Page Classification

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Mixture Models for Web Page Classification

Heat Transfer and Thermal Characteristics Effects on Moving Plate Impinging from Cu-Water Nanofluid Jet

2010 Second Asia-Pacific Conference on Information Processing (APCIP 2010)

作者： Bai JingHuaand Zhang XiaoXian School of Computer Science and technology a Beijing Institute of Technology a Beijing P.R.China a Li ZhiXin b and Li XiaoPing a Department of software b Changchun Institute of Technology b Chang Chun P.R.China b

This paper presents a method for designing semisupervised classifier trained on labeled and unlabeled *** explore the trade-off maximizing a generative likelihood of labeled and unlabeled ***,mixture models are an interesting and flexible model *** different uses of mixture models include for example generative models and density *** paper investigates semi-supervised learning of mixture models using a unified objective function taking both labeled and unlabeled data into *** conducted experiments on the WebKB and *** results show that unlabeled data results in improvement in classification accuracy over the supervised model.

关键词： semi-supervised learning mixture model generative model

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Journal of Thermal Science 2020年第1期29卷 182-193页

作者： DATTA Abanti KUMAR Sonal HALDER Pabitra Department of Aerospace Engineering and Applied Mechanics Indian Institute of Engineering Science and Technology

The present article is focused on modelling of flow and heat transfer behaviour of Cu-water nanofluid in a confined slot jet impingement on hot moving *** parameters such as various moving plate velocities,nanoparticles at various concentrations,variation in turbulent Reynolds number and jet nozzle to plate distance have been considered to study the flow field and convective heat transfer performance of the *** of distribution of local and average Nusselt number and skin friction coefficients at the plate surface are shown to elucidate the heat transfer and fluid flow *** analysis of both stream function and isotherm contours are carried out to perceive the flow pattern and heat transfer mechanism due to moving *** results revealed that average Nusselt number significantly rises with plate velocity in addition with jet inlet Reynolds *** of the average Nusselt numbers are presented.

关键词： Cu-water nanofluid,multiphase mixture model moving plate jet impingement CFD

Effects of porous material on transient natural convection heat transfer of nano-fluids inside a triangular chamber

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Chinese Journal of Chemical Engineering 2020年第5期28卷 1203-1213页

作者： Mohsen Izadi Mechanical Engineering Department Faculty of EngineeringLorestan UniversityKhorramabadIran

This study numerically investigates the impact of porous materials,nano-particle types,and their concentrations on transient natural convection heat transfer of nano-fluid inside a porous chamber with a triangular *** governing equations of the two-phase mixture model are separated on the computational domain and solved using the Finite Volume Method,taking into account the Darcy–Brinkman model for porous *** was observed that convection heat transfer inside the triangular chamber consists of three stages named initial,transient,and *** features of each step are provided in *** results suggested that the use of a hybrid nano-fluid(water/aluminum oxide-cooper)inside a porous glass material and an increase in volume fraction of nano-particles have adverse effects on heat transfer *** contrast,as the nano-particle volume fraction of the single nano-fluid(water/aluminum oxide)inside the chamber increased,convection heat transfer rate *** the same time,it was observed that the use of both nano-fluids(single and hybrid)in the porous environment of the aluminum foam could improve convection.

关键词： Transient natural convection mixture model Darcy-Brinlanan model Rayleigh-Benard instability Triangular chamber

A MODIFIED LIKELIHOOD RATIO TEST FOR HOMOGENEITY IN BIVARIATE NORMAL mixtureS OF TWO SAMPLES

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Journal of Systems Science & Complexity 2009年第3期22卷 460-468页

作者： Qingzhu LEI·Yongsong QINSchool of Mathematical Sciences,Guangxi Normal University,Guilin 541004,China. School of Mathematical Sciences Guangxi Normal University Guilin 541004 China

This paper investigates the asymptotic properties of a modified likelihood ratio statistic for testing homogeneity in bivariate normal mixture models of two samples. The asymptotic null distribution of the modified li... 详细信息

关键词： Asymptotic distribution mixture model likelihood ratio test.