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Calculate Joint Probability Distribution of Steady Directed Cyclic Graph with Local Data and Domain Casual Knowledge 被引量:1
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作者 Qin Zhang Kun Qiu Zhan Zhang 《China Communications》 SCIE CSCD 2018年第7期146-155,共10页
It is desired to obtain the joint probability distribution(JPD) over a set of random variables with local data, so as to avoid the hard work to collect statistical data in the scale of all variables. A lot of work has... It is desired to obtain the joint probability distribution(JPD) over a set of random variables with local data, so as to avoid the hard work to collect statistical data in the scale of all variables. A lot of work has been done when all variables are in a known directed acyclic graph(DAG). However, steady directed cyclic graphs(DCGs) may be involved when we simply combine modules containing local data together, where a module is composed of a child variable and its parent variables. So far, the physical and statistical meaning of steady DCGs remain unclear and unsolved. This paper illustrates the physical and statistical meaning of steady DCGs, and presents a method to calculate the JPD with local data, given that all variables are in a known single-valued Dynamic Uncertain Causality Graph(S-DUCG), and thus defines a new Bayesian Network with steady DCGs. The so-called single-valued means that only the causes of the true state of a variable are specified, while the false state is the complement of the true state. 展开更多
关键词 directed cyclic graph probabilistic reasoning parameter learning causality complex network
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Emotion recognition of Uyghur speech using uncertain linear discriminant analysis
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作者 Tashpolat Nizamidin Zhao Li +2 位作者 Zhang Mingyang Xu Xinzhou Askar Hamdulla 《Journal of Southeast University(English Edition)》 EI CAS 2017年第4期437-443,共7页
To achieve efficient a d compact low-dimensional features for speech emotion recognition,a novel featurereduction method using uncertain linear discriminant analysis is proposed.Using the same principles as for conven... To achieve efficient a d compact low-dimensional features for speech emotion recognition,a novel featurereduction method using uncertain linear discriminant analysis is proposed.Using the same principles as for conventional linear discriminant analysis(LDA),uncertainties of the noisy or distorted input data ae employed in order to estimate maximaiy discriminant directions.The effectiveness of the proposed uncertain LDA(ULDA)is demonstrated in the Uyghur speech emotion recognition task.The emotional features of Uyghur speech,especially,the fundamental fequency and formant,a e analyzed in the collected emotional data.Then,ULDA is employed in dimensionality reduction of emotional features and better performance is achieved compared with other dimensionality reduction techniques.The speech emotion recognition of Uyghur is implemented by feeding the low-dimensional data to support vector machine(SVM)based on the proposed ULDA.The experimental results show that when employing a appropriate uncertainty estimation algorithm,uncertain LDA outperforms the conveetional LDA counterpart on Uyghur speech emotion recognition. 展开更多
关键词 Uyghur language speech emotion corpus PITCH FORMANT uncertain linear discriminant analysis (ULDA)
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Electrical capacitance volume tomography for measurement soil water infiltration in vessel experiments
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作者 Muhammad Mukhlisin Marlin Ramadhan Baidillah Mohd Raihan Taha 《Journal of Central South University》 SCIE EI CAS 2014年第1期358-364,共7页
Electrical capacitance volume tomography(ECVT) is a recently-developed technique for real-time,non-invasive 3D monitoring of processes involving materials with strong contrasts in dielectric permittivity.This work is ... Electrical capacitance volume tomography(ECVT) is a recently-developed technique for real-time,non-invasive 3D monitoring of processes involving materials with strong contrasts in dielectric permittivity.This work is first application of the method to visualization of water flow in soil.We describe the principles behind the method,and then demonstrate its use with a simple laboratory infiltration experiment.32 ECVT sensors were installed on the sides of an empty PVC column.Water was poured into the column at a constant rate,and ECVT data were collected every second.The column was then packed with dry sand and again supplied with water at a constant rate with data collected every second.Data were analyzed to give bulk average water contents,which proved consistent with the water supply rates.Data were also analyzed to give 3D images(216 voxels) allowing visualization of the water distribution during the experiments.Result of this work shows that water infiltration into the soil,wall flow,progress of the unstable wetting front and the final water distribution are clearly visible. 展开更多
关键词 soil water infiltration electrical capacitance volume tomography real time imaging
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New method of calculating formation parameters of low permeability gas reservoir
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作者 SHANG Xi-tao HE Shun-li LI Xiu-sheng 《Journal of Energy and Power Engineering》 2009年第3期34-39,共6页
The data of modified isochronal testing of gas well is just used to calculate gas well deliverability. Fully utilizing well test data make it possible to obtain formation parameters, such as gas well deliverability, e... The data of modified isochronal testing of gas well is just used to calculate gas well deliverability. Fully utilizing well test data make it possible to obtain formation parameters, such as gas well deliverability, effective permeability and skin factor at the same time. Based on transient flow theory, the pressure drawdown equation of gas unsteady seepage can be deducted. One simulated case is used to illustrate the applicability of the proposed method. The result of analyzed case shows that the proposed method can provide accurate estimate of formation permeability and skin factor compared with the method of Homer curves. 展开更多
关键词 gas reservoir well testing pressure test formation parameters METHOD
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建设工程施工降水计量系统的应用探讨
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作者 赵海云 李晓梅 贾陆璐 《北京水务》 2019年第S01期36-39,共4页
立足建设工程施工现场,针对现场降水条件,制定4种计量方案,搭建施工降水计量系统,实现各个计量点数据的实时上传,水量数据的日报、月报,为降水单位水资源税的缴纳提供数据依据.系统上线后,管理人员和施工人员能够实时查看当前降水点的... 立足建设工程施工现场,针对现场降水条件,制定4种计量方案,搭建施工降水计量系统,实现各个计量点数据的实时上传,水量数据的日报、月报,为降水单位水资源税的缴纳提供数据依据.系统上线后,管理人员和施工人员能够实时查看当前降水点的水量数据,自动获取月降水量,同时各个降水点的月水量数据自动推送到报税平台,方便建设单位核查水量及时缴税,提高了水资源税的上缴效率.通过本系统的建设,为建设单位施工降水的水资源税上缴提供数据支撑,提高了工程建设单位的节水意识,推动了水资源费改税工作的持续开展. 展开更多
关键词 施工降水 计量系统 水资源税 数据率定
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ROBUST OUTPUT FEEDBACK STABILIZATION OF NONLINEAR NETWORKED SYSTEMS VIA A FINITE DATA-RATE COMMUNICATION CHANNEL 被引量:1
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作者 Teddy M. CHENG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2011年第1期1-13,共13页
This paper addresses a robust stabilization problem of a class of uncertain nonlinear systems using output measurements via a finite data-rate communication channel. The authors assumes that there exist an observer an... This paper addresses a robust stabilization problem of a class of uncertain nonlinear systems using output measurements via a finite data-rate communication channel. The authors assumes that there exist an observer and a control law for the systems in the absence of any finite data-rate communi- cation channel. Based on the observer and the control law, the authors constructs an encoder/decoder pair and provides a sufficient condition, including suitable sampling period and data rate, which will guarantee the stability of the closed-loop systems when a finite data-rate communication channel is introduced. 展开更多
关键词 Control over communication networks nonlinear control output feedback uncertain systems.
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Accelerated steered response power method for sound source localization via clustering search 被引量:5
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作者 ZHAO XiaoYan TANG Jie +1 位作者 ZHOU Lin WU ZhenYang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第7期1329-1338,共10页
The steered response power-phase transform (SRP-PHAT) sound source localization algorithm is robust in a real environment. However, the large computation complexity limits the practical application of SRP-PHAT. For a ... The steered response power-phase transform (SRP-PHAT) sound source localization algorithm is robust in a real environment. However, the large computation complexity limits the practical application of SRP-PHAT. For a microphone array, each location corresponds to a set of time differences of arrival (TDOAs), and this paper collects them into a TDOA vector. Since the TDOA vectors in the adjacent regions are similar, we present a fast algorithm based on clustering search to reduce the computation complexity of SRP-PHAT. In the training stage, the K-means or Iterative Self-Organizing Data Analysis Technique (ISODATA) clustering algorithm is used to find the centroid in each cluster with similar TDOA vectors. In the procedure of sound localization, the optimal cluster is found by comparing the steered response powers (SRPs) of all centroids. The SRPs of all candidate locations in the optimal cluster are compared to localize the sound source. Experiments both in simulation environments and real environments have been performed to compare the localization accuracy and computational load of the proposed method with those of the conventional SRP-PHAT algorithm. The results show that the proposed method is able to reduce the computational load drastically and maintains almost the same localization accuracy and robustness as those of the conventional SRP-PHAT algorithm. The difference in localization performance brought by different clustering algorithms used in the training stage is trivial. 展开更多
关键词 sound source localization microphone array steered response power clustering search
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Fatigue reliability assessment for bridge welded details using long-term monitoring data 被引量:24
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作者 DENG Yang DING YouLiang +1 位作者 LI AiQun ZHOU GuangDong 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第12期3371-3381,共11页
A reliability assessment method of fatigue life based on the long-term monitoring data is developed for welded details in steel box girder,and the application research is presented with examples of welded rib-to-deck ... A reliability assessment method of fatigue life based on the long-term monitoring data is developed for welded details in steel box girder,and the application research is presented with examples of welded rib-to-deck details in Runyang Bridges. Firstly the fatigue damage limit-state function is established based on S-N curves and Miner's rule,and the probability distribution characteristics of the coefficients in the function are discussed in detail. The uncertainties in fatigue loading effects are mainly studied based on long-term monitoring data. In the traditional studies,only the uncertainty of equivalent stress range is considered in fatigue reliability assessment. However,stress cycle number is also treated as a random variable in this paper because we know traffic flow every day differs in a thousand ways. Then the optimization method is employed to calculate the fatigue reliability. After studying the changing law of the reliability indices with time and the effect of the randomness of stress cycle number on reliability,the effect of the traffic growth on the reliability is studied. This study shows that the uncertainty in the fatigue life of the welded details can be well studied based on structural health monitoring,so it is necessary to carry out long-term strain monitoring of the welded details for accurate fatigue reliability assessment during the whole service period. 展开更多
关键词 steel box girder fatigue loading effects equivalent stress range stress cycle number fatigue reliability traffic growth
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