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Experimental Study on the Initial Position Distribution of Taylor Bubbles in Cryogenic Upward Inclined Tubes 被引量:1
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作者 张华 王淑华 +1 位作者 刘夷平 王经 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期340-343,共4页
An experimental study was carried out to understand the phenomena of the boiling flow of liquid nitrogen in inclined tubes with closed bottom by using the high speed digital camera.The tubes in the experiment are 0.01... An experimental study was carried out to understand the phenomena of the boiling flow of liquid nitrogen in inclined tubes with closed bottom by using the high speed digital camera.The tubes in the experiment are 0.018 m and 0.014 m in inner diameter and 1.0 m in length.The range of the inclination angles is 0-45° from the vertical.The statistical method is employed to analyze the experimental data.The experiment was focused on the effect of the inclination angle on the initial position distribution of Taylor bubbles.The formation criterion of Taylor bubbles was confirmed by analyzing the images of Taylor bubbles.The experimental results show that the initial position of Taylor bubble increased first,and then decreased with the increasing inclination angle,with the maximum at 30°.The standard deviation of the initial position of Taylor bubble in tubes was different with different inner diameters.The lognormal shape was fitted to the measured the initial position distributions of Taylor bubbles in the cryogenic tubes. 展开更多
关键词 CRYOGENIC NITROGEN BOILING initial position distribution Taylor bubble inclined tube
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Game Theory Based Model for Predictive Analytics Using Distributed Position Function
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作者 Mirhossein Mousavi Karimi Shahram Rahimi 《International Journal of Intelligence Science》 2024年第1期22-47,共26页
This paper presents a game theory-based method for predicting the outcomes of negotiation and group decision-making problems. We propose an extension to the BDM model to address problems where actors’ positions are d... This paper presents a game theory-based method for predicting the outcomes of negotiation and group decision-making problems. We propose an extension to the BDM model to address problems where actors’ positions are distributed over a position spectrum. We generalize the concept of position in the model to incorporate continuous positions for the actors, enabling them to have more flexibility in defining their targets. We explore different possible functions to study the role of the position function and discuss appropriate distance measures for computing the distance between the positions of actors. To validate the proposed extension, we demonstrate the trustworthiness of our model’s performance and interpretation by replicating the results based on data used in earlier studies. 展开更多
关键词 Distributed position Function Game Theory Group Decision Making Predictive Analytics
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Fiber Migration and Distribution of Twist at Different Radial Positions of Rotor Yarn-by Hi-Scope Video Microscope System 被引量:5
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作者 王善元 CHEUNG H.W. +2 位作者 张宏伟 LO M.T. 卢明德 《Journal of Donghua University(English Edition)》 EI CAS 2002年第3期45-47,共3页
This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions o... This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions of tracer fibers were measured in three dimensions accurately, and the migration index and the twist distribution at different radial positions of rotor yarn were calculated and analyzed. This research result serves to provide useful references for further study on the structural mechanics of rotor spun yarn. 展开更多
关键词 rotor yarn fiber migration twist distribution at different radial positions.
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Distribution and segregation of dissolved elements in pipeline slab 被引量:3
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作者 Jianhua Liu Yanping Bao +3 位作者 Xian Dong Taiquan Li Yi Ren Shuai Zhang 《Journal of University of Science and Technology Beijing》 CSCD 2007年第3期212-218,共7页
The chemical composition in a cross section of a high grade pipeline slab was measured point by point (in a scale of 1 μm) using original position statistic distribution analysis (OPA). The result indicated that ... The chemical composition in a cross section of a high grade pipeline slab was measured point by point (in a scale of 1 μm) using original position statistic distribution analysis (OPA). The result indicated that negative segregation strips of Si, Mn, Mo, Ni, Cr, Nb, Cu, Ti, and V exist in the two sides 24 mm away from the central line, with a width of 8-12 mm, Negative segregation inside the central line is more severe than that outside the central line, and the highest positive segregation of the elements appears closely by the inner sides of the negative segregation strips. No obvious negative segregation strip of S and P is found. Segregation of the elements in the central area is higher than that in the outer and inner arc areas. The segregation of C, Ti, S, and P is high and that of Cr, Cu, Si, and Mn is low in the slab. 展开更多
关键词 original position statistic distribution analysis (OPA) SEGREGATION negative segregation PIPELINE
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Distributed adaptive direct position determination based on diffusion framework 被引量:2
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作者 Wei Xia Wei Liu Lingfeng Zhu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期28-38,共11页
The conventional direct position determination(DPD) algorithm processes all received signals on a single sensor.When sensors have limited computational capabilities or energy storage,it is desirable to distribute th... The conventional direct position determination(DPD) algorithm processes all received signals on a single sensor.When sensors have limited computational capabilities or energy storage,it is desirable to distribute the computation among other sensors.A distributed adaptive DPD(DADPD)algorithm based on diffusion framework is proposed for emitter localization.Unlike the corresponding centralized adaptive DPD(CADPD) algorithm,all but one sensor in the proposed algorithm participate in processing the received signals and estimating the common emitter position,respectively.The computational load and energy consumption on a single sensor in the CADPD algorithm is distributed among other computing sensors in a balanced manner.Exactly the same iterative localization algorithm is carried out in each computing sensor,respectively,and the algorithm in each computing sensor exhibits quite similar convergence behavior.The difference of the localization and tracking performance between the proposed distributed algorithm and the corresponding CADPD algorithm is negligible through simulation evaluations. 展开更多
关键词 emitter localization time difference of arrival(TDOA) direct position determination(DPD) distributed adaptive DPD(DADPD) diffusion framework.
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The Fourier Transformations of Positive Distributions on Lorentz Group SO(3,1)
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作者 Zhu Li College of Mathematics and Statistics, Wuhan University, Wuhan 430072,China 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第3期631-642,共12页
With the aid of Plancherel-Godement Theorem, we prove that every positive distributionT onSO (3, 1) which is bi-invariant underSO(3) corresponds to a measure μ on ω=∝σC|s(2-s)>=0∝, and μ can be decomposed int... With the aid of Plancherel-Godement Theorem, we prove that every positive distributionT onSO (3, 1) which is bi-invariant underSO(3) corresponds to a measure μ on ω=∝σC|s(2-s)>=0∝, and μ can be decomposed intoμ=μ 1+μ 2, whereμ 1 is a bounded measure on 0<=s<=2 andμ 2 is slowly increasing measure on (sχC|Re(s)=1)} 展开更多
关键词 K-bi-in-invariant positive distribution spherical Fourier transformation Laplace-Beltrami operator
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Study on original position statistic quantitative method for the content of Al in inclusions from steels
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作者 LI Dongling,LI Meiling,JIA Yunhai and WANG Haizhou Central Iron & Steel Research Institute,Beijng 100081,China 《Baosteel Technical Research》 CAS 2010年第S1期120-,共1页
The inclusions of Al in steels have great influence on the properties and the quality of steels.But there are some difficulties on the content determination of Al inclusions with accuracy and rapidity.Conventional qua... The inclusions of Al in steels have great influence on the properties and the quality of steels.But there are some difficulties on the content determination of Al inclusions with accuracy and rapidity.Conventional quantity analysis of stable inclusions is electrolysis method with the disadvantages of long analytical period,trivial operation and a little loss of some fine and instable oxides.The content of insoluble aluminum can be obtained by the subtraction between the content of total Al and acid soluble Al determined by chemical methods with the disadvantage of complicate procedure.Original position statistic distribution analysis(OPA) can be used for the determination of inclusions by collecting and discriminating the signals produced by single spark discharge in the way of no pre-sparking,scanning and emitting continuously.In this study the element of Al in some spectrum certified reference materials of carbon and medium or low-alloyed steels was analyzed by original opposition statistic distribution technique.Two quantitative mathematical models used by original position distribution analysis technology for the analysis of the content of Al inclusions have been investigated and been applied to the analysis of the content of Al inclusions in many kinds of spectrum certified reference materials and some medium and low-alloyed steel samples.The scope of application of the models and their limited conditions were discussed.It was found that the results calculated by OPA had great difference with the value by chemical method for some samples with the total content of Al above 0.2%.The reason is that some intensity of abnormal sparks have gone beyond the range of the largest intensity that can be determined by the instrument so that there is a certain deviation on the identification of abnormal sparks and the calculation of threshold value.It was found that the size distribution of Al inclusions had a great influence on the application of the two models.For most of certified reference materials for spectrum analysis and real steel samples the results of the content of Al in inclusions calculated by model 1 was satisfied and had good coincidence with the value of insoluble Al by chemical method. But for the samples with so many large inclusions of Al existed,the influence of intensity should be considered because the signal increase did not vary in the form of simple function.So model 2 was more suitable for the content calculation of Al in inclusions in this case.In order to choose suitable model to be used it is suggested that the size distribution of inclusions should be determined by OPA before content determination of Al in inclusions. The results of the content of Al inclusions calculated by the selected mathematical model were satisfied and had good coincidence with the value of insoluble Al obtained by the subtraction between the content of total Al and soluble Al determined by chemical methods when the content of total aluminum was below 0.2%. 展开更多
关键词 STEEL aluminum inclusions original position statistic distribution analysis mathematical quantitative model insoluble aluminum
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Reliability of gas holdup measurements using the differential pressure method in a cyclone-static micro-bubble flotation column 被引量:1
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作者 Xia Wencheng Yang Jianguo Wang Yuling 《Mining Science and Technology》 EI CAS 2011年第6期797-801,共5页
Gas holdup is one of the key parameters in flotation process. Gas holdup as measured by a differential pressure method was investigated and the relative errors compared to the average gas holdup from the volume expans... Gas holdup is one of the key parameters in flotation process. Gas holdup as measured by a differential pressure method was investigated and the relative errors compared to the average gas holdup from the volume expansion method. The errors were used to establish optimum measurement positions. The results show that the measurement position should be in the middle of the column and in the region half way from the center to the wall (the half-radius). The gas holdup along the axial direction is lower at the bottom and higher at the top of the floatation column. The gas holdup along the radial direction is lower near the wall and higher near the center of the flotation column. The average gas holdup measure- ment can be replaced by regional gas holdup values. 展开更多
关键词 Gas holdup distribution Differential pressure method Measurement positions Axial direction Radial direction
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Positive Stable Frailty Approach in the Construction of Dependence Life-Tables
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作者 Onchere Walter Weke Patrick +1 位作者 Joseph Ottieno Ogutu Carolyne 《Open Journal of Statistics》 2021年第4期506-523,共18页
Dependence may arise in insurance when the insureds are clustered into groups e.g. joint-life annuities. This dependence may be produced by sharing a common risk acting on mortality of members of the group. Various de... Dependence may arise in insurance when the insureds are clustered into groups e.g. joint-life annuities. This dependence may be produced by sharing a common risk acting on mortality of members of the group. Various dependence models have been considered in literature</span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">;</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> however, the focus has been on either the lower-tail dependence alone or upper-tail dependence alone. This article implements the frailty dependence approach to life insurance problems where most applications have been within medical setting. Our strategy is to use the conditional independence assumption given an observed association measure in a positive stable frailty approach to account for both lower and upper-tail dependence. The model is calibrated on the association of Kenyan insurers 2010 male and female published rates. The positive stable model is then proposed to construct dependence life-tables and generate life annuity payment streams in the competitive Kenyan market. 展开更多
关键词 Joint-Life Annuity Life-Table Functions Shared Frailty Model Positive Stable distribution Bayesian Inference
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ANALYTIC FUNCTIONALS AND A NEW DISTRIBUTION THEORY OVER INFINITE DIMENSIONAL SPACES
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作者 黄志远 任佳刚 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1996年第4期507-514,共8页
The authors establish a Gel’fand-van Eijndhoven-de Graaf type triplet over infinite dimensional space and investigate some of its fundamental properties.
关键词 Analyticity space Gaussian space Positive distributions
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Position optimization of particular solution sources for distributed source boundary point method by volume velocity-matching
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作者 WU Shaowei XIANG Yang LI Shengyang 《Chinese Journal of Acoustics》 CSCD 2015年第2期123-137,共15页
Choosing particular solution source and its position have great influence on accu- racy of sound field prediction in distributed source boundary point method. An optimization method for determining the position of par... Choosing particular solution source and its position have great influence on accu- racy of sound field prediction in distributed source boundary point method. An optimization method for determining the position of particular solution sources is proposed to get high accu- racy prediction result. In this method, tripole is chosen as the particular solution. The upper limit frequency of calculation is predicted by setting 1% volume velocity relative error limit using vibration velocity of structure surface. Then, the optimal position of particular solution sources, in which the relative error of volume velocity is minimum, is determined within the range of upper limit frequency by searching algorithm using volume velocity matching. The transfer matrix between pressure and surface volume velocity is constructed in the optimal position. After that, the sound radiation of structure is calculated by the matrix. The results of numerical simulation show that the calculation error is significantly reduced by the proposed method. When there are vibration velocity measurement errors, the calculation errors can be controlled within 5% by the method. 展开更多
关键词 position optimization of particular solution sources for distributed source boundary point method by volume velocity-matching
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Study of Human Action Recognition Based on Improved Spatio-temporal Features 被引量:7
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作者 Xiao-Fei Ji Qian-Qian Wu +1 位作者 Zhao-Jie Ju Yang-Yang Wang 《International Journal of Automation and computing》 EI CSCD 2014年第5期500-509,共10页
Most of the exist action recognition methods mainly utilize spatio-temporal descriptors of single interest point while ignoring their potential integral information, such as spatial distribution information. By combin... Most of the exist action recognition methods mainly utilize spatio-temporal descriptors of single interest point while ignoring their potential integral information, such as spatial distribution information. By combining local spatio-temporal feature and global positional distribution information(PDI) of interest points, a novel motion descriptor is proposed in this paper. The proposed method detects interest points by using an improved interest point detection method. Then, 3-dimensional scale-invariant feature transform(3D SIFT) descriptors are extracted for every interest point. In order to obtain a compact description and efficient computation, the principal component analysis(PCA) method is utilized twice on the 3D SIFT descriptors of single frame and multiple frames. Simultaneously, the PDI of the interest points are computed and combined with the above features. The combined features are quantified and selected and finally tested by using the support vector machine(SVM) recognition algorithm on the public KTH dataset. The testing results have showed that the recognition rate has been significantly improved and the proposed features can more accurately describe human motion with high adaptability to scenarios. 展开更多
关键词 Action recognition spatio-temporal interest points 3-dimensional scale-invariant feature transform (3D SIFT) positional distribution information dimension reduction
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Supporting Various Top-k Queries over Uncertain Datasets
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作者 LI Wenfeng FU Zufa +2 位作者 WANG Liwei LI Deyi PENG Zhiyong 《Wuhan University Journal of Natural Sciences》 CAS 2014年第1期84-92,共9页
There have been many researches and semantics in answering top-k queries on uncertain data in various applications. However, most of these semantics must consume much of their time in computing position probability. O... There have been many researches and semantics in answering top-k queries on uncertain data in various applications. However, most of these semantics must consume much of their time in computing position probability. Our approach to support various top-k queries is based on position probability distribution (PPD) sharing. In this paper, a PPD-tree structure and several basic operations on it are proposed to support various top-k queries. In addition, we proposed an approximation method to improve the efficiency of PPD generation. We also verify the effectiveness and efficiency of our approach by both theoretical analysis and experiments. 展开更多
关键词 top-k queries uncertain data position probability distribution
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