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A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching
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作者 Quanbo Ge Yang Cheng +3 位作者 Hong Li Ziyi Ye Yi Zhu Gang Yao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1424-1437,共14页
For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the... For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and symmetry.Some com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment. 展开更多
关键词 Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.
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Comparison of Type I Error Rates of Siegel-Tukey and Savage Tests among Non-Parametric Tests
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作者 Sahib Ramazanov Hakan Çora 《Open Journal of Applied Sciences》 2024年第9期2393-2410,共18页
This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviat... This study aimed to examine the performance of the Siegel-Tukey and Savage tests on data sets with heterogeneous variances. The analysis, considering Normal, Platykurtic, and Skewed distributions and a standard deviation ratio of 1, was conducted for both small and large sample sizes. For small sample sizes, two main categories were established: equal and different sample sizes. Analyses were performed using Monte Carlo simulations with 20,000 repetitions for each scenario, and the simulations were evaluated using SAS software. For small sample sizes, the I. type error rate of the Siegel-Tukey test generally ranged from 0.045 to 0.055, while the I. type error rate of the Savage test was observed to range from 0.016 to 0.041. Similar trends were observed for Platykurtic and Skewed distributions. In scenarios with different sample sizes, the Savage test generally exhibited lower I. type error rates. For large sample sizes, two main categories were established: equal and different sample sizes. For large sample sizes, the I. type error rate of the Siegel-Tukey test ranged from 0.047 to 0.052, while the I. type error rate of the Savage test ranged from 0.043 to 0.051. In cases of equal sample sizes, both tests generally had lower error rates, with the Savage test providing more consistent results for large sample sizes. In conclusion, it was determined that the Savage test provides lower I. type error rates for small sample sizes and that both tests have similar error rates for large sample sizes. These findings suggest that the Savage test could be a more reliable option when analyzing variance differences. 展开更多
关键词 non-parametric Test Siegel-Tukey Test Savage Test Monte Carlo Simulation Type I Error
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A non-parametric indicator Kriging method for generating coastal sediment type map 被引量:2
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作者 刘付程 彭俊 张存勇 《Marine Science Bulletin》 2012年第1期57-67,共11页
Coastal sediment type map has been widely used in marine economic and engineering activities, but the traditional mapping methods had some limitations due to their intrinsic assumption or subjectivity. In this paper, ... Coastal sediment type map has been widely used in marine economic and engineering activities, but the traditional mapping methods had some limitations due to their intrinsic assumption or subjectivity. In this paper, a non-parametric indicator Kriging method has been proposed for generating coastal sediment map. The method can effectively avoid mapping subjectivity, has no special requirements for the sample data to meet second-order stationary or normal distribution, and can also provide useful information on the quantitative evaluation of mapping uncertainty. The application of the method in the southern sea area of Lianyungang showed that much more convincing mapping results could be obtained compared with the traditional methods such as IDW, Kriging and Voronoi diagram under the same condition, so the proposed method was applicable with great utilization value. 展开更多
关键词 sediment type non-parametric indicator Kriging uncertaintY mapping
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A Short-Term Traffic Flow Forecasting Method Based on a Three-Layer K-Nearest Neighbor Non-Parametric Regression Algorithm 被引量:7
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作者 Xiyu Pang Cheng Wang Guolin Huang 《Journal of Transportation Technologies》 2016年第4期200-206,共7页
Short-term traffic flow is one of the core technologies to realize traffic flow guidance. In this article, in view of the characteristics that the traffic flow changes repeatedly, a short-term traffic flow forecasting... Short-term traffic flow is one of the core technologies to realize traffic flow guidance. In this article, in view of the characteristics that the traffic flow changes repeatedly, a short-term traffic flow forecasting method based on a three-layer K-nearest neighbor non-parametric regression algorithm is proposed. Specifically, two screening layers based on shape similarity were introduced in K-nearest neighbor non-parametric regression method, and the forecasting results were output using the weighted averaging on the reciprocal values of the shape similarity distances and the most-similar-point distance adjustment method. According to the experimental results, the proposed algorithm has improved the predictive ability of the traditional K-nearest neighbor non-parametric regression method, and greatly enhanced the accuracy and real-time performance of short-term traffic flow forecasting. 展开更多
关键词 Three-Layer Traffic Flow Forecasting K-Nearest Neighbor non-parametric Regression
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An Improved Non-Parametric Method for Multiple Moving Objects Detection in the Markov Random Field 被引量:1
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作者 Qin Wan Xiaolin Zhu +3 位作者 Yueping Xiao Jine Yan Guoquan Chen Mingui Sun 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第7期129-149,共21页
Detecting moving objects in the stationary background is an important problem in visual surveillance systems.However,the traditional background subtraction method fails when the background is not completely stationary... Detecting moving objects in the stationary background is an important problem in visual surveillance systems.However,the traditional background subtraction method fails when the background is not completely stationary and involves certain dynamic changes.In this paper,according to the basic steps of the background subtraction method,a novel non-parametric moving object detection method is proposed based on an improved ant colony algorithm by using the Markov random field.Concretely,the contributions are as follows:1)A new nonparametric strategy is utilized to model the background,based on an improved kernel density estimation;this approach uses an adaptive bandwidth,and the fused features combine the colours,gradients and positions.2)A Markov random field method based on this adaptive background model via the constraint of the spatial context is proposed to extract objects.3)The posterior function is maximized efficiently by using an improved ant colony system algorithm.Extensive experiments show that the proposed method demonstrates a better performance than many existing state-of-the-art methods. 展开更多
关键词 Object detection non-parametric method markov random field
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Non-parametric camera calibration method using single-axis rotational target
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作者 FU Luhua REN Zeguang +2 位作者 WANG Peng SUN Changku ZHANG Baoshang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第1期1-11,共11页
The ability to build an imaging process is crucial to vision measurement.The non-parametric imaging model describes an imaging process as a pixel cluster,in which each pixel is related to a spatial ray originated from... The ability to build an imaging process is crucial to vision measurement.The non-parametric imaging model describes an imaging process as a pixel cluster,in which each pixel is related to a spatial ray originated from an object point.However,a non-parametric model requires a sophisticated calculation process or high-cost devices to obtain a massive quantity of parameters.These disadvantages limit the application of camera models.Therefore,we propose a novel camera model calibration method based on a single-axis rotational target.The rotational vision target offers 3D control points with no need for detailed information of poses of the rotational target.Radial basis function(RBF)network is introduced to map 3D coordinates to 2D image coordinates.We subsequently derive the optimization formulization of imaging model parameters and compute the parameter from the given control points.The model is extended to adapt the stereo camera that is widely used in vision measurement.Experiments have been done to evaluate the performance of the proposed camera calibration method.The results show that the proposed method has superiority in accuracy and effectiveness in comparison with the traditional methods. 展开更多
关键词 camera calibration rotational target non-parametric model
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Exponential Continuous Non-Parametric Neural Identifier With Predefined Convergence Velocity
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作者 Mariana Ballesteros Rita Q.Fuentes-Aguilar Isaac Chairez 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第6期1049-1060,共12页
This paper addresses the design of an exponential function-based learning law for artificial neural networks(ANNs)with continuous dynamics.The ANN structure is used to obtain a non-parametric model of systems with unc... This paper addresses the design of an exponential function-based learning law for artificial neural networks(ANNs)with continuous dynamics.The ANN structure is used to obtain a non-parametric model of systems with uncertainties,which are described by a set of nonlinear ordinary differential equations.Two novel adaptive algorithms with predefined exponential convergence rate adjust the weights of the ANN.The first algorithm includes an adaptive gain depending on the identification error which accelerated the convergence of the weights and promotes a faster convergence between the states of the uncertain system and the trajectories of the neural identifier.The second approach uses a time-dependent sigmoidal gain that forces the convergence of the identification error to an invariant set characterized by an ellipsoid.The generalized volume of this ellipsoid depends on the upper bounds of uncertainties,perturbations and modeling errors.The application of the invariant ellipsoid method yields to obtain an algorithm to reduce the volume of the convergence region for the identification error.Both adaptive algorithms are derived from the application of a non-standard exponential dependent function and an associated controlled Lyapunov function.Numerical examples demonstrate the improvements enforced by the algorithms introduced in this study by comparing the convergence settings concerning classical schemes with non-exponential continuous learning methods.The proposed identifiers overcome the results of the classical identifier achieving a faster convergence to an invariant set of smaller dimensions. 展开更多
关键词 Exponential Lyapunov functions learning laws non-parametric identifier predefined convergence rate
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Analysis of Trends in Drought with the Non-Parametric Approach in Vietnam: A Case Study in Ninh Thuan Province
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作者 Nguyen Hoang Tuan Truong Thanh Canh 《American Journal of Climate Change》 2021年第1期51-84,共34页
A quantitative study was used in the study of the tendency to change drought indicators in Vietnam through the Ninh Thuan province case study. The research data are temperature and precipitation data of 11 stations fr... A quantitative study was used in the study of the tendency to change drought indicators in Vietnam through the Ninh Thuan province case study. The research data are temperature and precipitation data of 11 stations from 1986 to 2016 inside and outside Ninh Thuan province. To do the research, the author uses a non-parametric analysis method and the drought index calculation method. Specifically, with the non-parametric method, the author uses the analysis, Mann-Kendall (MK) and Theil-Sen (Sen’s slope), and to analyze drought, the author uses the Standardized Precipitation Index (SPI) and the Moisture Index (MI). Two Softwares calculated in this study are ProUCL 5.1 and MAKENSEN 1.0 by the US Environmental Protection Agency and Finnish Meteorological Institute. The calculation results show that meteorological drought will decrease in the future with areas such as Phan Rang, Song Pha, Quan The, Ba Thap tend to increase very clearly, while Tam My and Nhi Ha tend to increase very clearly short. With the agricultural drought, the average MI results increased 0.013 per year, of which Song Pha station tended to increase the highest with 0.03 per year and lower with Nhi Ha with 0.001 per year. The forecast results also show that by the end of the 21st century, the SPI tends to decrease with SPI 1 being <span style="white-space:nowrap;">&#8722;</span>0.68, SPI 3 being <span style="white-space:nowrap;">&#8722;</span>0.40, SPI 6 being <span style="white-space:nowrap;">&#8722;</span>0.25, SPI 12 is 0.42. Along with that is the forecast that the MI index will increase 0.013 per year to 2035, the MI index is 0.93, in 2050 it is 1.13, in 2075 it will be 1.46, and by 2100 it is 1.79. Research results will be used in policymaking, environmental resources management agencies, and researchers to develop and study solutions to adapt and mitigate drought in the context of variable climate change. 展开更多
关键词 DROUGHT MANN-KENDALL Sen’s Slope non-parametric
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Bayesian Non-Parametric Mixture Model with Application to Modeling Biological Markers
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作者 Mercy K. Peter Levi Mbugua Anthony Wanjoya 《Journal of Data Analysis and Information Processing》 2019年第4期141-152,共12页
The effect of treatment on patient’s outcome can easily be determined through the impact of the treatment on biological events. Observing the treatment for patients for a certain period of time can help in determinin... The effect of treatment on patient’s outcome can easily be determined through the impact of the treatment on biological events. Observing the treatment for patients for a certain period of time can help in determining whether there is any change in the biomarker of the patient. It is important to study how the biomarker changes due to treatment and whether for different individuals located in separate centers can be clustered together since they might have different distributions. The study is motivated by a Bayesian non-parametric mixture model, which is more flexible when compared to the Bayesian Parametric models and is capable of borrowing information across different centers allowing them to be grouped together. To this end, this research modeled Biological markers taking into consideration the Surrogate markers. The study employed the nested Dirichlet process prior, which is easily peaceable on different distributions for several centers, with centers from the same Dirichlet process component clustered automatically together. The study sampled from the posterior by use of Markov chain Monte carol algorithm. The model is illustrated using a simulation study to see how it performs on simulated data. Clearly, from the simulation study it was clear that, the model was capable of clustering data into different clusters. 展开更多
关键词 BAYESIAN non-parametric Nested DIRICHLET PROCESS BIOMARKER Clustering Surrogate MARKERS DIRICHLET PROCESS Markov Chain Monte Carlo
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Sufficient variable selection of high dimensional nonparametric nonlinear systems based on Fourier spectrum of density-weighted derivative
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作者 Bing SUN Changming CHENG +1 位作者 Qiaoyan CAI Zhike PENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第11期2011-2022,共12页
The variable selection of high dimensional nonparametric nonlinear systems aims to select the contributing variables or to eliminate the redundant variables.For a high dimensional nonparametric nonlinear system,howeve... The variable selection of high dimensional nonparametric nonlinear systems aims to select the contributing variables or to eliminate the redundant variables.For a high dimensional nonparametric nonlinear system,however,identifying whether a variable contributes or not is not easy.Therefore,based on the Fourier spectrum of densityweighted derivative,one novel variable selection approach is developed,which does not suffer from the dimensionality curse and improves the identification accuracy.Furthermore,a necessary and sufficient condition for testing a variable whether it contributes or not is provided.The proposed approach does not require strong assumptions on the distribution,such as elliptical distribution.The simulation study verifies the effectiveness of the novel variable selection algorithm. 展开更多
关键词 nonlinear system identification variable selection Fourier spectrum non-parametric nonlinear system
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Oxygen uptake response to switching stairs exercise by non-parametric modeling
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作者 Hairong Yu Chenyu Zhang +2 位作者 Kai Cao Hamzah M.Alqudah Steven Weidong Su 《Control Theory and Technology》 EI CSCD 2024年第2期315-325,共11页
Oxygen uptake plays a crucial role in the evaluation of endurance performance during exercise and is extensively utilized for metabolic assessment. This study records the oxygen uptake during the exercise phase (i.e.,... Oxygen uptake plays a crucial role in the evaluation of endurance performance during exercise and is extensively utilized for metabolic assessment. This study records the oxygen uptake during the exercise phase (i.e., ascending or descending) of the stair exercise, utilizing an experimental dataset that includes ten participants and covers various exercise periods. Based on the designed experiment protocol, a non-parametric modeling method with kernel-based regularization is generally applied to estimate the oxygen uptake changes during the switching stairs exercise, which closely resembles daily life activities. The modeling results indicate the effectiveness of the non-parametric modeling approach when compared to fixed-order models in terms of accuracy, stability, and compatibility. The influence of exercise duration on estimated fitness reveals that the model of the phase-oxygen uptake system is not time-invariant related to respiratory metabolism regulation and muscle fatigue. Consequently, it allows us to study the humans’ conversion mechanism at different metabolic rates and facilitates the standardization and development of exercise prescriptions. 展开更多
关键词 non-parametric modeling Interval stair training exercise Kernel method.Cardiorespiratory response Oxygen uptake
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Evaluation of Rainfall Tendency for the Twentieth Century over Indira Sagar Region in Central India
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作者 Rituraj Shukla Deepak Khare +4 位作者 Ramesh P. Rudra Priti Tiwari Himanshu Sharma Prasad Daggupati Pradeep Goel 《American Journal of Climate Change》 2024年第1期47-68,共22页
The study investigates long-term changes in annual and seasonal rainfall patterns in the Indira Sagar Region of Madhya Pradesh, India, from 1901 to 2010. Agriculture sustainability, food supply, natural resource devel... The study investigates long-term changes in annual and seasonal rainfall patterns in the Indira Sagar Region of Madhya Pradesh, India, from 1901 to 2010. Agriculture sustainability, food supply, natural resource development, and hydropower system reliability in the region rely heavily on monsoon rainfall. Monthly rainfall data from three stations (East Nimar, Barwani, and West Nimar) were analyzed. Initially, the pre-whitening method was applied to eliminate serial correlation effects from the rainfall data series. Subsequently, statistical trends in annual and seasonal rainfall were assessed using both parametric (student-t test) and non-parametric tests [Mann-Kendall, Sen’s slope estimator, and Cumulative Sum (CUSUM)]. The magnitude of the rainfall trend was determined using Theil-Sen’s slope estimator. Spatial analysis of the Mann-Kendall test on an annual basis revealed a statistically insignificant decreasing trend for Barwani and East Nimar and an increasing trend for West Nimar. On a seasonal basis, the monsoon season contributes a significant percentage (88.33%) to the total annual rainfall. The CUSUM test results indicated a shift change detection in annual rainfall data for Barwani in 1997, while shifts were observed in West and East Nimar stations in 1929. These findings offer valuable insights into regional rainfall behavior, aiding in the planning and management of water resources and ecological systems. 展开更多
关键词 PRECIPITATION PARAMETRIC non-parametric Tests Trend Analysis Serial Correlations
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Parameters Estimation of a Bivariate Generalized Poisson Distribution with Applications to Metabolic Syndrome Data
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作者 Mohamed M. Shoukri 《Open Journal of Statistics》 2024年第5期467-480,共14页
Background: Bivariate count data are commonly encountered in medicine, biology, engineering, epidemiology and many other applications. The Poisson distribution has been the model of choice to analyze such data. In mos... Background: Bivariate count data are commonly encountered in medicine, biology, engineering, epidemiology and many other applications. The Poisson distribution has been the model of choice to analyze such data. In most cases mutual independence among the variables is assumed, however this fails to take into accounts the correlation between the outcomes of interests. A special bivariate form of the multivariate Lagrange family of distribution, names Generalized Bivariate Poisson Distribution, is considered in this paper. Objectives: We estimate the model parameters using the method of maximum likelihood and show that the model fits the count variables representing components of metabolic syndrome in spousal pairs. We use the likelihood local score to test the significance of the correlation between the counts. We also construct confidence interval on the ratio of the two correlated Poisson means. Methods: Based on a random sample of pairs of count data, we show that the score test of independence is locally most powerful. We also provide a formula for sample size estimation for given level of significance and given power. The confidence intervals on the ratio of correlated Poisson means are constructed using the delta method, the Fieller’s theorem, and the nonparametric bootstrap. We illustrate the methodologies on metabolic syndrome data collected from 4000 spousal pairs. Results: The bivariate Poisson model fitted the metabolic syndrome data quite satisfactorily. Moreover, the three methods of confidence interval estimation were almost identical, meaning that they have the same interval width. 展开更多
关键词 Lagrange Distributions Double Poisson Maximum Likelihood Estimation Score Test of Independence Higher Order Moments non-parametric Bootstrap
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水中甲醛检测仪的校准及不确定度评定
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作者 朱培娟 濮程 +2 位作者 张明婷 邵微维 黄佳意 《计量与测试技术》 2024年第6期17-20,共4页
水中甲醛检测仪被广泛应用于环境检测、废水监测和水污染防治。由于目前尚未有相关的检定规程和校准规范。因此,为了满足该类仪器的溯源需求,本文提出了校准方法,并对校准的示值误差进行了不确定度评定。
关键词 水中甲醛检测仪 溯源 校准 不确定度
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高精度直流大电流源的两种校准方法及其应用限度
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作者 陈习权 刘珂 +1 位作者 林婷 曾佳旭 《计量与测试技术》 2023年第6期15-18,共4页
基于当前100A以上高精度直流大电流源国家计量技术规范缺失的现状,介绍两种计量校准方法,即精密电流转换标准、数字多用表为测量标准的电流电压转换法、高精度直流大电流表为测量标准的标准电流表法。阐述两种校准方法的工作原理和注意... 基于当前100A以上高精度直流大电流源国家计量技术规范缺失的现状,介绍两种计量校准方法,即精密电流转换标准、数字多用表为测量标准的电流电压转换法、高精度直流大电流表为测量标准的标准电流表法。阐述两种校准方法的工作原理和注意事项,通过相应的测量不确定度对比分析和实验验证,证明其合理可行,并给出二者的应用限度。 展开更多
关键词 直流大电流源 电流电压转换法 标准电流表法 测量不确定度
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基于序贯三支决策的半监督目标检测算法 被引量:1
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作者 宋法兴 苗夺谦 张红云 《计算机科学》 CSCD 北大核心 2023年第10期1-6,共6页
深度学习对大规模数据的需求以及目标检测标注任务的复杂性促进了半监督目标检测任务的发展。近年来,半监督目标检测已经取得了很多优秀的成果。然而,伪标签中的不确定性依然是半监督目标检测研究中难以避免的问题,优越的半监督方法要... 深度学习对大规模数据的需求以及目标检测标注任务的复杂性促进了半监督目标检测任务的发展。近年来,半监督目标检测已经取得了很多优秀的成果。然而,伪标签中的不确定性依然是半监督目标检测研究中难以避免的问题,优越的半监督方法要求选取合适的过滤阈值来权衡伪标签的噪声信息比例和召回率,以最大程度保留准确有效的伪标签。为了解决此问题,在半监督检测的框架中引入了序贯三支决策算法,将模型输出的伪标签根据不同的筛选阈值划分为干净的前景标签、有噪声的前景标签,以及干净的背景标签,并对其采取不同的处理策略。对有噪声的前景标签采用负类学习损失来学习这些存在噪声的标签,避免学习到其中的噪声信息。实验结果表明了所提算法的性能优势,针对COCO数据集,在有监督数据占比只有10%的情况下,该方法实现了35.2%的检测精度,相比仅依靠有监督训练性能提升了11.34%。 展开更多
关键词 序贯三支决策 不确定性 负类学习 半监督学习 半监督目标检测
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建立测量不确定度测量模型之问题分析及简化处理方法 被引量:1
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作者 张长水 《计量与测试技术》 2023年第3期117-119,共3页
本文分析了测量不确定度评定中建立测量模型时存在的模糊问题,给出了测量不确定度评定中一些简化的数学处理方法。
关键词 测量模型 相关 测量不确定度
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Comparative Analysis of Climatic Change Trend and Change-Point Analysis for Long-Term Daily Rainfall Annual Maximum Time Series Data in Four Gauging Stations in Niger Delta
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作者 Masi G. Sam Ify L. Nwaogazie +4 位作者 Chiedozie Ikebude Jonathan O. Irokwe Diaa W. El Hourani Ubong J. Inyang Bright Worlu 《Open Journal of Modern Hydrology》 2023年第4期229-245,共17页
The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta re... The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta region of Nigeria. Using daily or 24-hourly annual maximum series (AMS) data with the Indian Meteorological Department (IMD) and the modified Chowdury Indian Meteorological Department (MCIMD) models were adopted to downscale the time series data. Mann-Kendall (MK) trend and Sen’s Slope Estimator (SSE) test showed a statistically significant trend for Uyo and Benin, while Port Harcourt and Warri showed mild trends. The Sen’s Slope magnitude and variation rate were 21.6, 10.8, 6.00 and 4.4 mm/decade, respectively. The trend change-point analysis showed the initial rainfall change-point dates as 2002, 2005, 1988, and 2000 for Uyo, Benin, Port Harcourt, and Warri, respectively. These prove positive changing climatic conditions for rainfall in the study area. Erosion and flood control facilities analysis and design in the Niger Delta will require the application of Non-stationary IDF modelling. 展开更多
关键词 Rainfall Time Series Data Climate Change Trend Analysis Variation Rate Change Point Dates non-parametric Statistical Test
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不对称信息、不确定性决策下的农业生物技术政府管理 被引量:4
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作者 马述忠 黄祖辉 傅夏仙 《中国软科学》 CSSCI 北大核心 2002年第9期19-23,共5页
本文在阐述不对称信息、不确定性决策内涵的基础上,从分析信息需求与信息供给缺口、政策调整压力入手,论述了“平衡法则”动力假设的主要内容,较为全面地表述了农业生物技术管理中的信息需求问题,并就这一问题提出了若干建议。
关键词 不对称信息 不确定性决策 农业生物技术 技术管理 信息需求
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气相色谱法测定西红杮中乙烯利残留量的不确定度分析 被引量:6
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作者 周艳明 汪霞 《食品工业科技》 CAS CSCD 北大核心 2008年第1期278-280,共3页
采用分层建模的方法,建立了气相色谱法对西红柿中乙烯利检测的不确定度评定的数学模型,对测量过程中的不确定度来源进行逐层分析和合成,并对检测过程产生的不确定度进行分析,得出了气相色谱法测定西红柿中乙烯利的不确定度的结果。
关键词 气相色谱 不确定度 乙烯利
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