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Unicity Theorems of Mesomorphic Functions with Three Weighted Sharing Values
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作者 WANG Xin-li CAO Zhang-long 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期110-116,共7页
In this paper,with the idea of weighted sharing values,we deal with the problem of uniqueness of mesomorphic functions sharing three weighted values.We obtain some theorems which improve the results of H X Yi and W R ... In this paper,with the idea of weighted sharing values,we deal with the problem of uniqueness of mesomorphic functions sharing three weighted values.We obtain some theorems which improve the results of H X Yi and W R L. 展开更多
关键词 mesomorphic functions weighted sharing values unicity theorem
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Value of MRI diffusion weighted imaging in localization of prostate cancer with whole-mount step section pathology
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作者 张凡 《外科研究与新技术》 2011年第4期258-259,共2页
Objective To evaluate the value of MRI diffusion weighted imaging in localization of prostate cancer with whole-mount step section pathology. Methods We treated 36 patients using laparoscopic radical prostatectomy fro... Objective To evaluate the value of MRI diffusion weighted imaging in localization of prostate cancer with whole-mount step section pathology. Methods We treated 36 patients using laparoscopic radical prostatectomy from Oct. 2009 to Jun. 2010. Patients who did not have an MRL /DWI examination or a surgical history of pros- 展开更多
关键词 MRI value of MRI diffusion weighted imaging in localization of prostate cancer with whole-mount step section pathology
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Weighted Multi-sensor Data Level Fusion Method of Vibration Signal Based on Correlation Function 被引量:7
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作者 BIN Guangfu JIANG Zhinong +1 位作者 LI Xuejun DHILLON B S 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期899-904,共6页
As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery... As the differences of sensor's precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery fault diagnosis.The traditional signal processing methods,such as classical inference and weighted averaging algorithm usually lack dynamic adaptability that is easy for trends to cause the faults to be misjudged or left out.To enhance the measuring veracity and precision of vibration signal in rotary machine multi-sensor vibration signal fault diagnosis,a novel data level fusion approach is presented on the basis of correlation function analysis to fast determine the weighted value of multi-sensor vibration signals.The approach doesn't require knowing the prior information about sensors,and the weighted value of sensors can be confirmed depending on the correlation measure of real-time data tested in the data level fusion process.It gives greater weighted value to the greater correlation measure of sensor signals,and vice versa.The approach can effectively suppress large errors and even can still fuse data in the case of sensor failures because it takes full advantage of sensor's own-information to determine the weighted value.Moreover,it has good performance of anti-jamming due to the correlation measures between noise and effective signals are usually small.Through the simulation of typical signal collected from multi-sensors,the comparative analysis of dynamic adaptability and fault tolerance between the proposed approach and traditional weighted averaging approach is taken.Finally,the rotor dynamics and integrated fault simulator is taken as an example to verify the feasibility and advantages of the proposed approach,it is shown that the multi-sensor data level fusion based on correlation function weighted approach is better than the traditional weighted average approach with respect to fusion precision and dynamic adaptability.Meantime,the approach is adaptable and easy to use,can be applied to other areas of vibration measurement. 展开更多
关键词 vibration signal MULTI-SENSOR data level fusion correlation function weighted value
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Risk analysis of extended reach wells in the Liuhua Oilfield,South China Sea,based on comprehensive fuzzy evaluation method 被引量:6
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作者 Zhang Hui Gao Deli Hao Zhiwei 《Petroleum Science》 SCIE CAS CSCD 2009年第2期172-175,共4页
Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling (ERD) is very important to prevent complex failures and to improve drilling e... Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling (ERD) is very important to prevent complex failures and to improve drilling efficiency. Nowadays there are few reports on how to analyze quantitatively the drilling risk for extended reach wells (ERWs). Based on the fuzzy set theory, a comprehensive fuzzy evaluation model for analyzing risks of ERD is proposed in this paper. Well B6ERW07 is a planned 8,000-meter ERW with a high ratio of horizontal displacement (HD) to vertical depth (VD) in the Liuhua Oilfield, the South China Sea, China. On the basis of the evaluation model developed in this study, the risk for drilling Well B6ERW07 was evaluated before drilling. The evaluation result shows that the success rate of drilling this well is predicted to be 51.9%, providing important rational and scientific information for the decisionmakers. 展开更多
关键词 Extended reach well risk analysis comprehensive fuzzy evaluation weight value
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一种有效的快速细化算法 被引量:5
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作者 杨兴炜 刘文予 白翔 《小型微型计算机系统》 CSCD 北大核心 2006年第7期1343-1346,共4页
提出一种有效的快速细化算法,包括两个步骤:首先通过建立w e igh t-va lue的概念对模板进行分类,然后按照分类后的模板对象素进行删除,使之成为由双层点或单层点构成的子图像;为保证能将双层点细化为单层点,提出两个模板,依据这两个模... 提出一种有效的快速细化算法,包括两个步骤:首先通过建立w e igh t-va lue的概念对模板进行分类,然后按照分类后的模板对象素进行删除,使之成为由双层点或单层点构成的子图像;为保证能将双层点细化为单层点,提出两个模板,依据这两个模板进行并行细化从而得到单象素骨架.实验证明这个方法是快速有效的. 展开更多
关键词 细化 模板 双层点 weightvalue
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Structural Stability of Weighted Digraph with Continuous Vertex Values
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作者 GAO ShuchunDepartment of Mathematics, Yantai Teachers College Yantai 264000, P.R. ChinaKANG YuInstitute of Mathematics, Academia Sinica, Beijing 100080, P.R.China 《Systems Science and Systems Engineering》 CSCD 1993年第4期297-301,共5页
In this paper, we give a sufficient condition about the stability of weighted digraph, which exceeds Roberts original judgement extremely.
关键词 Structural Stability of weighted Digraph with Continuous Vertex values
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Comparing practice-ready forecast models for weekly and monthly fluctuations of average daily traffic and enhancing accuracy by weighting methods 被引量:2
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作者 Andrea Pompigna Federico Rupi 《Journal of Traffic and Transportation Engineering(English Edition)》 2018年第4期239-253,共15页
Knowing daily traffic for the current year is recognized as being essential in many fields of transport analysis and practice, and short-term forecasting models offer a set of tools to meet these needs. This paper exa... Knowing daily traffic for the current year is recognized as being essential in many fields of transport analysis and practice, and short-term forecasting models offer a set of tools to meet these needs. This paper examines and compares the accuracy of three representative parametric and non-parametric prediction models, selected by the analysis of the numerous methods proposed in the literature for their good combi- nation of forecast accuracy and ease of calibration, using real-life data on Italian motorway stretches. Non-parametric K-NN regression model, Gaussian maximum likelihood model and double seasonality Holt-Winters exponential smoothing model confirm their goodness to predict the weekly and monthly fluctuations of average daily traffic with varying degrees of performance, while maintaining an easy use in professional practice, i.e. requiring ordinary professional skills and conventional analysis tools. Since combining several prediction models can give, on average, more accuracy than that of the individual models, the paper compares two weighting methods of easy implementation and susceptible to a direct use, namely the widely used information entropy method and the less widespread Shapley value method. Despite being less common than the information entropy method, the Shapley value method proves to be more capable in better combining single forecasts and produces improvements in the predictions for test data. With these remarks, the paper might be of interest to traffic technicians or analysts, in various and not uncommon tasks they might find in their work. 展开更多
关键词 Short-term traffic forecasting Non-parametric regression Gaussian maximum likelihood Double seasonal Holt-Winters exponential smoothing Entropy weighting method Shapley value weighting method
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Evaluation of tobacco soil fertility suitability of the Sanmenxia area, China, based on geographic information systems 被引量:1
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作者 Haisheng CHEN Yongfeng YANG +1 位作者 Guoshun LIU Zhengxian TONG 《Frontiers in Biology》 CSCD 2009年第4期453-459,共7页
The growth of flue-cured tobacco is sensitive to changes in environmental conditions.Excellent tobacco leaf production is strictly restricted by regional cultivated lands.For the purpose of reasonable utilization and ... The growth of flue-cured tobacco is sensitive to changes in environmental conditions.Excellent tobacco leaf production is strictly restricted by regional cultivated lands.For the purpose of reasonable utilization and scientific management of Sanmenxia tobacco fields,it is meaningful to evaluate the soil fertility suitability of tobacco crops quantitatively and objectively.In this study,the global positioning system(GPS)technology was used to obtain sample point information automatically.Based on the analysis of fertility properties of soil samples collected from the Sanmenxia tobacco planting regions in Henan Province,we present the index system of soil fertility suitability for tobacco crops.The integrated evaluation of soil fertility suitability was studied with six indices,including organic matter,pH value,available nitrogen(N),available phosphorus(P),available potassium(K),and chlorine(Cl–1)content of surface soil.The subjective grade value was calculated according to S-type and parabola-type functions of the effect of evaluation factors on tobacco crops.Further,the weight value of soil fertility suitability indices was calculated by the method of Hiberarchy analysis.The soil fertility suitability level was evaluated and classified.The suitability map of the Sanmenxia tobacco planting regions in Henan Province was then drawn with the geographic information system(GIS)software mapGIS.It was found that highly suitable fields were mainly distributed in the high mountains in the Southwestern part of the investigated regions where soil pH value and the contents of organic matter were medium,but the contents of available P and available K were higher,accounting for 79.36% of the whole area.Suitable fields were 17% of the whole area,mainly distributed in the middle part of the investigated regions where soil pH value was higher.Unsuitable fields existed in the northern-east and middle part of the Sanmenxia where the contents of soil Cl^(–)was very high,accounting for 3.51%of the whole regions. 展开更多
关键词 geographic information system TOBACCO eva-luation factors weight value soil fertility suitability
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