Like any industrial product, the vehicles also do have end of their service lives and ultimately result in end-of-life vehicle (ELV) at a certain stage of the vehicle life. The concern of this paper is to make a gener...Like any industrial product, the vehicles also do have end of their service lives and ultimately result in end-of-life vehicle (ELV) at a certain stage of the vehicle life. The concern of this paper is to make a general review on ELV management process and present a model for ELV management on the basis of green manufacturing so as to reduce the environmental impact and minimize the resources loss due to the ELVs. The various phases of vehicle life cycle starting from design, manufacturing and utilization, occurrence of ELV and then the storage, depollution, dismantling and finally the shredding and post shredder material processing phases of ELV for the resources recovery, all of these phases need to be considered to give totality to the model, which makes end-of-life vehicles management more benign for environment, and more efficient for the usage of resources.展开更多
Based on natural precipitation observations, impacts of different types of land use on processes of soil and water loss over purple soil related slopeland were studied by simulated rainfall experiments. Measurement da...Based on natural precipitation observations, impacts of different types of land use on processes of soil and water loss over purple soil related slopeland were studied by simulated rainfall experiments. Measurement data revealed that rainstorms and slope length are the essential factors accountable for soil and water loss on purple soil slopeland for intense rill erosion can be caused on 10 meter long purple soil slopes by high intensity rainfall. Under circumanstances of rainstorms, annual hedge plants grown on slopeland of 25 degrees can cause a reduction of runoff by 22 43 percent and that of erosion induced sand content by 94 98 percent. Stone bund horizontal terraces can lead to a runoff reduction by 62 67 percent in comparison with steep slopelands and that of erosion induced sediment by 97.8 99 percent. Soil and water loss can be substantially decreased on steep slopes by hedge plants with a cost of only 10 20 percent that of the stone bund horizontal terraces. Hence it is an effective way to control soil and water loss in terms of slopeland amelioration and utilization in the Three Gorges Reservoir Area.展开更多
Image processing technique was employed to analyze pitting corrosion morphologies of 304 stainless steel exposed to FeCl3 environments. BP neural network models were developed for the prediction of pitting corrosion m...Image processing technique was employed to analyze pitting corrosion morphologies of 304 stainless steel exposed to FeCl3 environments. BP neural network models were developed for the prediction of pitting corrosion mass loss using the obtained data of the total and the average pit areas which were extracted from pitting binary image. The results showed that the predicted results obtained by the 2-5-1 type BP neural network model are in good agreement with the experimental data of pitting corrosion mass loss. The maximum relative error of prediction is 6.78%.展开更多
In this paper, we introduce tail dependene measures for collateral losses from catastrophic events. To calculate these measures, we use bivariate compound process where a Cox process with shot noise intensity is used ...In this paper, we introduce tail dependene measures for collateral losses from catastrophic events. To calculate these measures, we use bivariate compound process where a Cox process with shot noise intensity is used to count collateral losses. A homogeneous Poisson process is also examined as its counterpart for the case where the catastrophic loss frequency rate is deterministic. Joint Laplace transform of the distribution of the aggregate collateral losses is derived and joint Fast Fourier transform is used to obtain the joint distributions of aggregate collateral losses. For numerical illustrations, a member of Farlie-Gumbel-Morgenstern copula with exponential margins is used. The figures of the joint distributions of collateral losses, their contours and numerical calculations of risk measures are also provided.展开更多
In this paper, we study the precise large deviations for the prospectiveloss process with consistently varying tails. The obtained results improve some related known ones.
Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function ...Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function by using its intensity function. The Bayesian analysis applicability to the Power Law Process is justified using real software failure times. The choice of a loss function is an important entity of the Bayesian settings. The analytical estimate of likelihood-based Bayesian reliability estimates of the Power Law Process under the squared error and Higgins-Tsokos loss functions were obtained for different prior knowledge of its key parameter. As a result of a simulation analysis and using real data, the Bayesian reliability estimate under the Higgins-Tsokos loss function not only is robust as the Bayesian reliability estimate under the squared error loss function but also performed better, where both are superior to the maximum likelihood reliability estimate. A sensitivity analysis resulted in the Bayesian estimate of the reliability function being sensitive to the prior, whether parametric or non-parametric, and to the loss function. An interactive user interface application was additionally developed using Wolfram language to compute and visualize the Bayesian and maximum likelihood estimates of the intensity and reliability functions of the Power Law Process for a given data.展开更多
害虫识别是害虫防治的关键基础,由于较难获得足够的害虫种类图像,如何使用少量标记图像构造害虫分类器是一个富有挑战性的问题。现有研究多采用匹配网络框架来解决这个问题,该框架使用元学习避免重新训练深度网络,然而主干网络的特征提...害虫识别是害虫防治的关键基础,由于较难获得足够的害虫种类图像,如何使用少量标记图像构造害虫分类器是一个富有挑战性的问题。现有研究多采用匹配网络框架来解决这个问题,该框架使用元学习避免重新训练深度网络,然而主干网络的特征提取能力有限,元学习算法没有提供较好的权重初始化策略,可能导致网络出现梯度消失或者梯度爆炸的情况。为了解决这一问题,该研究提出一种基于空间注意力增强ResNeSt-101和迁移元学习算法的小样本害虫分类器。首先,通过一个空间注意力模块增强ResNeSt-101以更好地提取害虫图像特征,即在ResNeSt-101的第1阶段的最大池化层之前以及在第2~4阶段的末尾分别附加集成空间注意力模块,并通过数值仿真确定空间注意力增强模块的最佳放置位置为第1阶段的最大池化层之前。随后,通过迁移学习策略初始化网络权重,进而通过元学习进行优化。为了避免网络出现梯度消失或者梯度爆炸的情况,在元学习算法中选择归一化的温度缩放交叉熵损失函数代替三元组损失函数。最后,通过计算查询图像和支持图像深度特征之间的相似度实现害虫分类。所提出方法在自建的害虫图像数据集AD0和MIP50上使用N-类K-例准确率和每张图像处理时间(the time of per image processing,TPIP)进行评估。害虫图像数据集的构建方式如下:首先对公共害虫图像数据集IP102和D0进行清洗,以消除由于英文害虫名称导致的歧义类别;然后移除卵、幼虫和蛹阶段的害虫图像,仅保留成虫阶段的图像。考虑到人工和时间成本,从清理后的IP102害虫数据集中选择50个类别构建MIP50害虫图像数据集。随后,通过害虫的拉丁名称从互联网搜索更多的害虫图像,生成AD0害虫图像数据集。自建的MIP50数据集包括来自IP102的50个类别的16424张成虫图像,AD0包含来自D0的所有40个类别的17112张成虫图像。试验结果表明,当测试集中只有少数未知类别的害虫图像时,本文方法在AD0数据集上的5-类10-例评估准确率达到了96.37%,在MIP50数据集上达到了76.91%。当测试集中同时存在几个未知和已知类别的害虫图像时,所提方法在AD0数据集上的5-类10-例设置下的识别准确率达到了93.73%,在MIP50数据集上达到90.60%。同时,本文方法的TPIP大约为0.44 ms,满足大多数场景下的实时害虫识别要求。此外,消融试验结果表明,基于空间注意力增强ResNeSt-101网络和迁移元学习的小样本害虫分类方法在AD0、MIP50数据集上对未知类别害虫图像的5-类10-例的识别准确率分别提升了5和3个百分点以上,具有良好应用前景。但未来研究中还需进一步研究本方法中存在的问题,如通过采用更好地表征支持集样本与查询集样本之间复杂关系的度量优化本工作中用到的度量以解决增加类别数可能导致分类准确率降低的问题,以及将所提方法应用于现实农业场景进行优化改进以更好提升本文方法的实用性。展开更多
We investigate the approximating capability of Markov modulated Poisson processes (MMPP) for modeling multifractal Internet traffic. The choice of MMPP is motivated by its ability to capture the variability and correl...We investigate the approximating capability of Markov modulated Poisson processes (MMPP) for modeling multifractal Internet traffic. The choice of MMPP is motivated by its ability to capture the variability and correlation in moderate time scales while being analytically tractable. Important statistics of traffic burstiness are described and a customized moment-based fitting procedure of MMPP to traffic traces is presented. Our methodology of doing this is to examine whether the MMPP can be used to predict the performance of a queue to which MMPP sample paths and measured traffic traces are fed for comparison respectively, in addition to the goodness-of-fit test of MMPP. Numerical results and simulations show that the fitted MMPP can approximate multifractal traffic quite well, i.e. accurately predict the queueing performance.展开更多
基金Funded by the Natural Science Foundation of Chongqing City, China (No. 47-19)
文摘Like any industrial product, the vehicles also do have end of their service lives and ultimately result in end-of-life vehicle (ELV) at a certain stage of the vehicle life. The concern of this paper is to make a general review on ELV management process and present a model for ELV management on the basis of green manufacturing so as to reduce the environmental impact and minimize the resources loss due to the ELVs. The various phases of vehicle life cycle starting from design, manufacturing and utilization, occurrence of ELV and then the storage, depollution, dismantling and finally the shredding and post shredder material processing phases of ELV for the resources recovery, all of these phases need to be considered to give totality to the model, which makes end-of-life vehicles management more benign for environment, and more efficient for the usage of resources.
文摘Based on natural precipitation observations, impacts of different types of land use on processes of soil and water loss over purple soil related slopeland were studied by simulated rainfall experiments. Measurement data revealed that rainstorms and slope length are the essential factors accountable for soil and water loss on purple soil slopeland for intense rill erosion can be caused on 10 meter long purple soil slopes by high intensity rainfall. Under circumanstances of rainstorms, annual hedge plants grown on slopeland of 25 degrees can cause a reduction of runoff by 22 43 percent and that of erosion induced sand content by 94 98 percent. Stone bund horizontal terraces can lead to a runoff reduction by 62 67 percent in comparison with steep slopelands and that of erosion induced sediment by 97.8 99 percent. Soil and water loss can be substantially decreased on steep slopes by hedge plants with a cost of only 10 20 percent that of the stone bund horizontal terraces. Hence it is an effective way to control soil and water loss in terms of slopeland amelioration and utilization in the Three Gorges Reservoir Area.
文摘Image processing technique was employed to analyze pitting corrosion morphologies of 304 stainless steel exposed to FeCl3 environments. BP neural network models were developed for the prediction of pitting corrosion mass loss using the obtained data of the total and the average pit areas which were extracted from pitting binary image. The results showed that the predicted results obtained by the 2-5-1 type BP neural network model are in good agreement with the experimental data of pitting corrosion mass loss. The maximum relative error of prediction is 6.78%.
文摘In this paper, we introduce tail dependene measures for collateral losses from catastrophic events. To calculate these measures, we use bivariate compound process where a Cox process with shot noise intensity is used to count collateral losses. A homogeneous Poisson process is also examined as its counterpart for the case where the catastrophic loss frequency rate is deterministic. Joint Laplace transform of the distribution of the aggregate collateral losses is derived and joint Fast Fourier transform is used to obtain the joint distributions of aggregate collateral losses. For numerical illustrations, a member of Farlie-Gumbel-Morgenstern copula with exponential margins is used. The figures of the joint distributions of collateral losses, their contours and numerical calculations of risk measures are also provided.
文摘In this paper, we study the precise large deviations for the prospectiveloss process with consistently varying tails. The obtained results improve some related known ones.
文摘Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function by using its intensity function. The Bayesian analysis applicability to the Power Law Process is justified using real software failure times. The choice of a loss function is an important entity of the Bayesian settings. The analytical estimate of likelihood-based Bayesian reliability estimates of the Power Law Process under the squared error and Higgins-Tsokos loss functions were obtained for different prior knowledge of its key parameter. As a result of a simulation analysis and using real data, the Bayesian reliability estimate under the Higgins-Tsokos loss function not only is robust as the Bayesian reliability estimate under the squared error loss function but also performed better, where both are superior to the maximum likelihood reliability estimate. A sensitivity analysis resulted in the Bayesian estimate of the reliability function being sensitive to the prior, whether parametric or non-parametric, and to the loss function. An interactive user interface application was additionally developed using Wolfram language to compute and visualize the Bayesian and maximum likelihood estimates of the intensity and reliability functions of the Power Law Process for a given data.
基金National Science Foundation of China(62172165)Science and Technology Planning Project of Guangdong Province under Grant(2021B1212040009)+2 种基金Natural Science Foundation of Guangdong Province(2022A1515010325)Guangzhou Basic and Applied Basic Research Project(202201010742)Science and Technology Program of Guangzhou(202206010116,201902010081,107126242281)。
文摘害虫识别是害虫防治的关键基础,由于较难获得足够的害虫种类图像,如何使用少量标记图像构造害虫分类器是一个富有挑战性的问题。现有研究多采用匹配网络框架来解决这个问题,该框架使用元学习避免重新训练深度网络,然而主干网络的特征提取能力有限,元学习算法没有提供较好的权重初始化策略,可能导致网络出现梯度消失或者梯度爆炸的情况。为了解决这一问题,该研究提出一种基于空间注意力增强ResNeSt-101和迁移元学习算法的小样本害虫分类器。首先,通过一个空间注意力模块增强ResNeSt-101以更好地提取害虫图像特征,即在ResNeSt-101的第1阶段的最大池化层之前以及在第2~4阶段的末尾分别附加集成空间注意力模块,并通过数值仿真确定空间注意力增强模块的最佳放置位置为第1阶段的最大池化层之前。随后,通过迁移学习策略初始化网络权重,进而通过元学习进行优化。为了避免网络出现梯度消失或者梯度爆炸的情况,在元学习算法中选择归一化的温度缩放交叉熵损失函数代替三元组损失函数。最后,通过计算查询图像和支持图像深度特征之间的相似度实现害虫分类。所提出方法在自建的害虫图像数据集AD0和MIP50上使用N-类K-例准确率和每张图像处理时间(the time of per image processing,TPIP)进行评估。害虫图像数据集的构建方式如下:首先对公共害虫图像数据集IP102和D0进行清洗,以消除由于英文害虫名称导致的歧义类别;然后移除卵、幼虫和蛹阶段的害虫图像,仅保留成虫阶段的图像。考虑到人工和时间成本,从清理后的IP102害虫数据集中选择50个类别构建MIP50害虫图像数据集。随后,通过害虫的拉丁名称从互联网搜索更多的害虫图像,生成AD0害虫图像数据集。自建的MIP50数据集包括来自IP102的50个类别的16424张成虫图像,AD0包含来自D0的所有40个类别的17112张成虫图像。试验结果表明,当测试集中只有少数未知类别的害虫图像时,本文方法在AD0数据集上的5-类10-例评估准确率达到了96.37%,在MIP50数据集上达到了76.91%。当测试集中同时存在几个未知和已知类别的害虫图像时,所提方法在AD0数据集上的5-类10-例设置下的识别准确率达到了93.73%,在MIP50数据集上达到90.60%。同时,本文方法的TPIP大约为0.44 ms,满足大多数场景下的实时害虫识别要求。此外,消融试验结果表明,基于空间注意力增强ResNeSt-101网络和迁移元学习的小样本害虫分类方法在AD0、MIP50数据集上对未知类别害虫图像的5-类10-例的识别准确率分别提升了5和3个百分点以上,具有良好应用前景。但未来研究中还需进一步研究本方法中存在的问题,如通过采用更好地表征支持集样本与查询集样本之间复杂关系的度量优化本工作中用到的度量以解决增加类别数可能导致分类准确率降低的问题,以及将所提方法应用于现实农业场景进行优化改进以更好提升本文方法的实用性。
文摘We investigate the approximating capability of Markov modulated Poisson processes (MMPP) for modeling multifractal Internet traffic. The choice of MMPP is motivated by its ability to capture the variability and correlation in moderate time scales while being analytically tractable. Important statistics of traffic burstiness are described and a customized moment-based fitting procedure of MMPP to traffic traces is presented. Our methodology of doing this is to examine whether the MMPP can be used to predict the performance of a queue to which MMPP sample paths and measured traffic traces are fed for comparison respectively, in addition to the goodness-of-fit test of MMPP. Numerical results and simulations show that the fitted MMPP can approximate multifractal traffic quite well, i.e. accurately predict the queueing performance.