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A NEW DATA ASSOCIATION ALGORITHM USING PROBABILITY HYPOTHESIS DENSITY FILTER 被引量:2
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作者 Huang Zhipei Sun Shuyan Wu Jiankang 《Journal of Electronics(China)》 2010年第2期218-223,共6页
Probability Hypothesis Density (PHD) filtering approach has shown its advantages in tracking time varying number of targets even when there are noise,clutter and misdetection. For linear Gaussian Mixture (GM) system,P... Probability Hypothesis Density (PHD) filtering approach has shown its advantages in tracking time varying number of targets even when there are noise,clutter and misdetection. For linear Gaussian Mixture (GM) system,PHD filter has a closed form recursion (GMPHD). But PHD filter cannot estimate the trajectories of multi-target because it only provides identity-free estimate of target states. Existing data association methods still remain a big challenge mostly because they are com-putationally expensive. In this paper,we proposed a new data association algorithm using GMPHD filter,which significantly alleviated the heavy computing load and performed multi-target trajectory tracking effectively in the meantime. 展开更多
关键词 Multi-target trajectory tracking Probability hypothesis Density (PHD) Gaussian mixture ((]M) model Multiple hypotheses detection Peak-to-track association
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Analysis of Krashen's Affective Filter Hypothesis
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作者 赵静 《海外英语》 2011年第8X期281-283,共3页
Affective filter hypothesis is one of Krashen's five hypotheses on Second Language Acquisition (SLA), and it states that a number of affective variables play a very important role in Second Language Acquisition. B... Affective filter hypothesis is one of Krashen's five hypotheses on Second Language Acquisition (SLA), and it states that a number of affective variables play a very important role in Second Language Acquisition. Based on the introduction of affective filter hypothesis, this paper will analyze the significance and shortcomings of this hypothesis. 展开更多
关键词 Krashen’s FIVE hypotheses AFFECTIVE filter hypothesIS SIGNIFICANCE and SHORTCOMINGS
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Why It Is Problematic to Calculate Probabilities of Findings Given Range Null Hypotheses
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作者 David Trafimow 《Open Journal of Statistics》 2017年第3期483-499,共17页
An important problem with null hypothesis significance testing, as it is normally performed, is that it is uninformative to reject a point null hypothesis [1]. A way around this problem is to use range null hypotheses... An important problem with null hypothesis significance testing, as it is normally performed, is that it is uninformative to reject a point null hypothesis [1]. A way around this problem is to use range null hypotheses [2]. But the use of range null hypotheses also is problematic. Aside from the usual issues of whether null hypothesis significance tests can be justified at all, there is an issue that is specific to range null hypotheses. It is not straightforward how to calculate the probability of the data given a range null hypothesis. The traditional way is to use the single point that maximizes the obtained p-value. The Bayesian alternative is to propose a prior probability distribution and integrate across it. Because frequentists and Bayesians disagree about a variety of issues, especially those pertaining to whether it is permissible to assign probabilities to hypotheses, and what gets lost in the shuffle is that the two camps actually come to different answers for the probability of the data given a range null hypothesis. Because the probability of the data given the hypothesis is a precursor for both camps, for drawing conclusions about hypotheses, different values for this probability for the different camps is crucial but seldom acknowledged. The goal of the present article is to bring out the problem in a manner accessible to researchers without strong mathematical or statistical backgrounds. 展开更多
关键词 RANGE hypotheses One-Tailed Test RANGE NULL hypothesIS Uninformative hypotheses
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MULTITARGET STATE AND TRACK ESTIMATION FOR THE PROBABILITY HYPOTHESES DENSITY FILTER 被引量:3
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作者 Liu Weifeng Han Chongzhao +2 位作者 Lian Feng Xu Xiaobin Wen Chenglin 《Journal of Electronics(China)》 2009年第1期2-12,共11页
The particle Probability Hypotheses Density (particle-PHD) filter is a tractable approach for Random Finite Set (RFS) Bayes estimation, but the particle-PHD filter can not directly derive the target track. Most existi... The particle Probability Hypotheses Density (particle-PHD) filter is a tractable approach for Random Finite Set (RFS) Bayes estimation, but the particle-PHD filter can not directly derive the target track. Most existing approaches combine the data association step to solve this problem. This paper proposes an algorithm which does not need the association step. Our basic ideal is based on the clustering algorithm of Finite Mixture Models (FMM). The intensity distribution is first derived by the particle-PHD filter, and then the clustering algorithm is applied to estimate the multitarget states and tracks jointly. The clustering process includes two steps: the prediction and update. The key to the proposed algorithm is to use the prediction as the initial points and the convergent points as the es- timates. Besides, Expectation-Maximization (EM) and Markov Chain Monte Carlo (MCMC) ap- proaches are used for the FMM parameter estimation. 展开更多
关键词 Probability hypotheses Density (PHD) Particle-PHD filter State and track estimation Finite mixture models
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Limited negative semantics based inductive hypotheses
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作者 叶风 王亚东 +1 位作者 徐晓飞 权光日 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期5-9,共5页
The Learning method of inductive logic programming evaluates the the quality of inductive hypotheses commonlyby how well the hypotheses cover training examples extensionally. Ths kind of evalution will be completely i... The Learning method of inductive logic programming evaluates the the quality of inductive hypotheses commonlyby how well the hypotheses cover training examples extensionally. Ths kind of evalution will be completely inapplica-ble to the situation where there are non-simple or noise examples. Based on Limited Negative semantics, This paperextends induction of simple examples to that of generalized ones and presents 3 criteria on accepting inductive hypothe-ses in order to fit for different goals of induction. The relation between inductive hypotheses and background knowledgeis also established in this Paper. The conclusions in this paper are helpful to implement learning algorithms and to ex-tend application fields of ILP. 展开更多
关键词 machine learning INDUCTIVE logic PROGRAMMING generalized EXAMPLES INDUCTIVE hypotheses
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Two Hypotheses of “Melanization” on Electrogalvanized Steel Surface
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作者 Ning LT, Derui ZHOU and Deyu LI Dept. of Applied Chemistry, Harbin Institute of Technology, Harbin 150001, China Kurachi Mitsuo Kyoto University, Kyoto 606-8283, Japan E-mail: liningt@ihw.com.cn 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第3期343-345,共3页
Melanization is harmful to the lightness of galvanized steel surface and also reduces the bonding force between a paint coat and the steel sheet. Experimental results showed that the hypothesis of Zn-Pb codeposition d... Melanization is harmful to the lightness of galvanized steel surface and also reduces the bonding force between a paint coat and the steel sheet. Experimental results showed that the hypothesis of Zn-Pb codeposition does not hold true, while the fact that PbSO4 micelles in sulfate bath settle on the coating surface support the second hypothesis. The authors come to the conclusions that (1) Any measure to eliminate PbSO4 micelles before or after passivation of the coating will prevent melanization; (2) PbSO4 micelles adsorbed on the surface of passivated film promote the growth of oxygen-deficient Zn oxide and result in the generation of melanization. 展开更多
关键词 Two hypotheses of MELANIZATION PB
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Sequential Test of Fuzzy Hypotheses
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作者 Mohammad Ghasem Akbari 《Open Journal of Statistics》 2011年第2期87-92,共6页
In testing statistical hypotheses, as in other statistical problems, we may be confronted with fuzzy concepts. This paper deals with the problem of testing hypotheses, when the hypotheses are fuzzy and the data are cr... In testing statistical hypotheses, as in other statistical problems, we may be confronted with fuzzy concepts. This paper deals with the problem of testing hypotheses, when the hypotheses are fuzzy and the data are crisp. We first give new definitions for notion of mass (density) probability function with fuzzy parameter, probability of type I and type II errors and then state and prove the sequential probability ratio test, on the basis of these new errors, for testing fuzzy hypotheses. Numerical examples are also provided to illustrate the approach. 展开更多
关键词 CANONICAL FUZZY Number FUZZY hypotheses Type I and II ERROR SIZES SEQUENTIAL PROBABILITY Ratio Test
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THE PROBABILITY HYPOTHESIS DENSITY FILTER WITH EVIDENCE FUSION
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作者 Liu Weifeng Xu Xiaobin 《Journal of Electronics(China)》 2009年第6期746-753,共8页
The original Probability Hypothesis Density (PHD) filter is a tractable algorithm for Multi-Target Tracking (MTT) in Random Finite Set (RFS) frameworks. In this paper,we introduce a novel Evidence PHD (E-PHD) filter w... The original Probability Hypothesis Density (PHD) filter is a tractable algorithm for Multi-Target Tracking (MTT) in Random Finite Set (RFS) frameworks. In this paper,we introduce a novel Evidence PHD (E-PHD) filter which combines the Dempster-Shafer (DS) evidence theory. The proposed filter can deal with the uncertain information,thus it forms target track. We mainly discusses the E-PHD filter under the condition of linear Gaussian. Research shows that the E-PHD filter has an analytic form of Evidence Gaussian Mixture PHD (E-GMPHD). The final experiment shows that the proposed E-GMPHD filter can derive the target identity,state,and number effectively. 展开更多
关键词 Probability hypotheses Density (PHD) Dempster-Shafer (DS) evidence Uncertain in-formation Evidence PHD (E-PHD) Evidence Gaussian Mixture PHD (E-GMPHD)
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Statistical Tests of Hypothesis Based Color Image Retrieval
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作者 K. Seetharaman S. Selvaraj 《Journal of Data Analysis and Information Processing》 2016年第2期90-99,共10页
This paper proposes a novel method based on statistical tests of hypotheses, such as F-ratio and Welch’s t-tests. The input query image is examined whether it is a textured or structured. If it is structured, the sha... This paper proposes a novel method based on statistical tests of hypotheses, such as F-ratio and Welch’s t-tests. The input query image is examined whether it is a textured or structured. If it is structured, the shapes are segregated into various regions according to its nature;otherwise, it is treated as textured image and considered the entire image as it is for the experiment. The aforesaid tests are applied regions-wise. First, the F-ratio test is applied, if the images pass the test, then it is proceeded to test the spectrum of energy, i.e. means of the two images. If the images pass both tests, then it is concluded that the two images are the same or similar. Otherwise, they differ. Since the proposed system is distribution-based, it is invariant for rotation and scaling. Also, the system facilitates the user to fix the number of images to be retrieved, because the user can fix the level of significance according to their requirements. These are the main advantages of the proposed system. 展开更多
关键词 F-Ratio Test Welch’s Test Tests of hypotheses Mean Average Precision Target Image Query Image
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Consistent Criteria for checking Hypotheses
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作者 Laura Eliauri Malkhaz Mumladze Zurab Zerakidze 《Journal of Mathematics and System Science》 2013年第10期514-518,共5页
This paper we study a consistent criterion for checking Hypotheses. Given definition of consistent criterion for checking hypotheses for family probability measures which were defined by Z. Zerakidze (see 5). We pro... This paper we study a consistent criterion for checking Hypotheses. Given definition of consistent criterion for checking hypotheses for family probability measures which were defined by Z. Zerakidze (see 5). We prove the necessary and sufficient conditions are obtained for the existence of consistent criteria of hypotheses. For example we clearly build of a consistent criteria for checking hypotheses. 展开更多
关键词 Consistent criterion ORTHOGONAL SEPARABLE hypotheses.
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Constrained Bayesian Method for Testing the Directional Hypotheses
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作者 Kartlos J. Kachiashvili N. K. Bansal I. A. Prangishvili 《Journal of Mathematics and System Science》 2018年第4期96-118,共23页
The paper discusses the generalization of constrained Bayesian method (CBM) for arbitrary loss functions and its application for testing the directional hypotheses. The problem is stated in terms of false and tru... The paper discusses the generalization of constrained Bayesian method (CBM) for arbitrary loss functions and its application for testing the directional hypotheses. The problem is stated in terms of false and true discovery rates. One more criterion of estimation of directional hypotheses tests quality, the Type III errors rate, is considered. The ratio among discovery rates and the Type III errors rate in CBM is considered. The advantage of CBM in comparison with Bayes and frequentist methods is theoretically proved and demonstrated by an example. 展开更多
关键词 CBM Bayesian test hypotheses testing false discovery rate type error rate.
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Hypotheses of "Harmonious Man": The Humanity Upgrade of Management and It's Sustainability Significance
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作者 SHunzhong XIA Guizhen YANG Yizhen WANG 《International English Education Research》 2015年第9期52-55,共4页
Hypotheses of humanity is the logical premise and foundation of institution design and perfect. "Political man" had boosted the sprout of ancient democracy polity, "economic man" has accelerated the development of... Hypotheses of humanity is the logical premise and foundation of institution design and perfect. "Political man" had boosted the sprout of ancient democracy polity, "economic man" has accelerated the development of market economy in immediate and modern times, "free man" described the blueprint of future society, and "harmonious man" will promote the construction of harmonious society and the development of management to conducting oneself so as to serve others. The article explains the theory headstream, abstract ways, basic intension and sustainability effect to the hypotheses of"harmonious man". 展开更多
关键词 humanity hypotheses harmonious man conducting oneself so as to serve others sustainability.
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Krashen's Input Hypothesis and Affective Filter Hypothesis'Enlightenment to the Vocational English Teaching
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作者 LI Chun-xia 《海外英语》 2013年第14期41-42,共2页
The Krashen's second language acquisition theory have two important assumptions: input hypothesis and the affective filter hypothesis. They can guide and inspire vocational teaching, because they start from the st... The Krashen's second language acquisition theory have two important assumptions: input hypothesis and the affective filter hypothesis. They can guide and inspire vocational teaching, because they start from the student's learning situation, guide teachers to adjust their teaching methods, and provide better service for teaching and learning. This paper mainly analyzes the Krashen's input hypothesis and the affective filter hypothesis'enlightenment to the vocational English teaching. 展开更多
关键词 Krashsen INPUT hypothesIS AFFECTIVE FILTER hypothe
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Reasons for Modern Warming:Hypotheses and Facts
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作者 Nikolai Nikolaevich Zavalishin 《Journal of Atmospheric Science Research》 2022年第1期11-17,共7页
Two hypotheses of modern warming are considered:natural and anthro­pogenic.The probabilities of each of them are compared.It is proved that the hypothesis of natural warming is much more likely than the hypothesi... Two hypotheses of modern warming are considered:natural and anthro­pogenic.The probabilities of each of them are compared.It is proved that the hypothesis of natural warming is much more likely than the hypothesis of anthropogenic warming.It is shown that the displacement of the Sun from the center of mass of the solar system directly affects the temperature of the surface atmosphere in the synoptic regions of Eurasia.This result corresponds to the model of E.P.Borysenkov with variations of the solar constant or,equivalently,with variations of the Bond albedo. 展开更多
关键词 hypotheses NATURAL ANTHROPOGENIC Temperature Lower atmosphere ALBEDO Solar displacement
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Unraveling the enigma of salivary uric acid in periodontitis:Independent association,mechanistic insights,and future trajectories
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作者 Dan-Dan Shi Jing Ding Ju Tian 《World Journal of Clinical Cases》 2025年第27期125-130,共6页
This article explores the association between salivary uric acid(UA)and periodontitis,systematically analyzing its dual roles and research progress.Studies indicate that UA acts as a primary antioxidant in saliva unde... This article explores the association between salivary uric acid(UA)and periodontitis,systematically analyzing its dual roles and research progress.Studies indicate that UA acts as a primary antioxidant in saliva under physiological conditions(accounting for 70%),protecting periodontal tissues by scavenging reactive oxygen species.However,when gum disease becomes severe,UA can switch roles and fuel inflammation,worsening tissue damage.Lorente et al’s research found an independent inverse correlation between salivary UA levels and periodontitis severity(odds ratio=6.14,P=0.001),establishing 111 nmol/mL as a diagnostic threshold(area under the curve=66%).Nevertheless,limitations include sample heterogeneity and failure to distinguish between gingivitis and periodontitis.Mechanistically,three hypotheses are proposed:The Antioxidant Depletion Hypothesis(UA oxidation consumption leading to feedback loops),the Microbial Metabolic Hijacking Hypothesis(pathogens utilizing UA as a carbon source to disrupt redox balance),and the Epithelial Barrier Dysfunction Hypothesis(UA deficiency causing downregulation of tight junction proteins).Future research should prioritize longitudinal cohorts to validate predictive value,integrate multi-omics to explore dysregulated signatures,and develop UA supplementation or targeted antioxidant therapies.This study provides novel insights into periodontitis diagnosis and mechanisms,advancing the application of salivary biomarkers in precision periodontics. 展开更多
关键词 Diagnostic biomarkers Mechanistic hypotheses Oxidative stress PERIODONTITIS Salivary uric acid
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Linguistic Hypotheses Concerning Natural Language Understanding 被引量:1
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作者 袁毓林 《Social Sciences in China》 1995年第4期131-142,218,共13页
关键词 ROCK Linguistic hypotheses Concerning Natural Language Understanding
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接受域类型差异对多重备选假设数据探测法的影响分析
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作者 余航 王坚 +2 位作者 王乐洋 宁一鹏 赵伟 《武汉大学学报(信息科学版)》 北大核心 2025年第10期1978-1990,共13页
当先验单位权方差因子已知时,超椭球体或超多面体接受域常被用于多重备选假设数据探测法,以探测与识别观测值中的粗差,但不同接受域类型对该方法的影响缺乏分析。首先,分别基于残差和闭合差构建的Baarda w-检验统计量,综合分析接受域类... 当先验单位权方差因子已知时,超椭球体或超多面体接受域常被用于多重备选假设数据探测法,以探测与识别观测值中的粗差,但不同接受域类型对该方法的影响缺乏分析。首先,分别基于残差和闭合差构建的Baarda w-检验统计量,综合分析接受域类型的差异对检验空间、检验决策概率计算、最小可探测偏差(minimal detectable bias,MDB)及正确识别率的影响,总结了目前3种计算检验决策概率的方法;然后,以二维闭合差的检验空间为基础,揭示了不同接受域类型导致的正确识别率差异与函数模型几何间的对应关系。数值实验结果表明,不同接受域类型不仅会导致MDB的不同,还会影响检验决策概率的大小,导致正确识别率存在差异。分析该差异与模型几何间的关系有助于改善网形设计,降低接受域类型的差异对备选模型正确识别率的影响。 展开更多
关键词 数据探测法 多重假设检验 检验空间 正确识别 最小可探测偏差
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EM algorithm and its application to testing hypotheses
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作者 房祥忠 陈家鼎 《Science China Mathematics》 SCIE 2003年第5期718-723,共6页
The conventional method for testing hypotheses is to find an exact or asymptotic distributionof a test statistic. But when the model is complex and the sample size is small, difficulty often arises. Thispaper aims to ... The conventional method for testing hypotheses is to find an exact or asymptotic distributionof a test statistic. But when the model is complex and the sample size is small, difficulty often arises. Thispaper aims to present a method for finding maximum probability with the help of EM algorithm. For any fixedsample size, this method can be used not only to obtain an accurate test but also to check the real level ofa test which is build by large sample theory. Especially, while doing this, one needs neither the accurate norasymptotic distribution of the test statistic. So the method is easily performed and is especially useful for small samples. 展开更多
关键词 TEST of hypotheses EM algorithm MAXIMUM probability SMALL sample recursivealgorithm.
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A Class of Asymptotically Optimal Sequential Tests for Composite Hypotheses'
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作者 陈家鼎 FredJ.Hickernell 《Science China Mathematics》 SCIE 1994年第11期1314-1324,共11页
Suppose that X has density f(x,θ)=exp(θx-ψ(θ)} (with respect to some measure v),where θ∈(θ,θ),∞≤θ≤+∞.Consider the problem of testing the hypothesis θ≤θ0 against θ≥θ1 for some given θ0 and θ1 (θ&... Suppose that X has density f(x,θ)=exp(θx-ψ(θ)} (with respect to some measure v),where θ∈(θ,θ),∞≤θ≤+∞.Consider the problem of testing the hypothesis θ≤θ0 against θ≥θ1 for some given θ0 and θ1 (θ<θ0<θ1<θ).A class of truncated sequential tests is introduced with type Ⅰ and type Ⅱ error probabilities not exceeding a and β,respectively.The expected sample sizes of these tests are shown to be asymptotically minimal for all θ as α+β↓0 展开更多
关键词 SEQUENTIAL testing COMPOSITE hypotheses ASYMPTOTICALLY optimal STOCHASTIC process of EXPONENTIAL type.
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Molecular group dynamics study on slip flow of thin fluid film based on the Hamaker hypotheses
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作者 ZHOU JianFeng, SHAO ChunLei & GU BoQin College of Mechanical and Power Engineering, Nanjing University of Technology, Nanjing 210009, China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第7期1833-1838,共6页
The thin fluid film was assumed to consist of a number of spherical fluid molecular groups and the attractive forces of molecular group pairs were calculated by the derived equation according to the three Hamaker homo... The thin fluid film was assumed to consist of a number of spherical fluid molecular groups and the attractive forces of molecular group pairs were calculated by the derived equation according to the three Hamaker homogeneous material hypotheses. Regarding each molecular group as a dynamics individual, the simulation method for the shearing motion of multilayer fluid molecular groups, which was initiated by two moving walls, was proposed based on the Verlet velocity iterative algorithm. The simulations reveal that the velocities of fluid molecular groups change about their respective mean velocities within a narrow range in steady state. It is also found that the velocity slips occur at the wall boundary and in a certain number of fluid film layers close to the wall. Because the dimension of molecular group and the number of group layers are not restricted, the hypothetical thickness of fluid film model can be enlarged from nanometer to micron by using the proposed simulation method. 展开更多
关键词 Hamaker hypotheses MOLECULAR GROUP VELOCITY SLIP LENNARD-JONES potential
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