Rank-based analysis of repeated measures block designs

A rank-based inference is developed for repeated measures balanced incomplete block and randomized complete block designs using a suitable dispersion function. Asymptotic distributions of rank estimators are developed after establishing approximate linearity of the gradient vector of the dispersion function. Unlike available nonparametric procedures for those designs, estimation and testing are tied together. Three different test statistics are developed for testing the linear hypotheses. Friedman's (1937) statistic and Durbin's (1951) statistic are particular cases of one of the three proposed statistics. An estimate of a scale parameter which appears in the ARE expression as well as as in the variences and covariances of the rank estimators is discussed.     

Statistical Analysis of Coins Lost in Circulation

The loss rate of coins in the Israeli pound (IL) series issued in Israel in 1960–1979 is estimated, and the connection between it and the characteristics of the coins is examined. A lifetime model with time-dependent hazard rate and an estimation procedure for the model parameters are presented. The estimates are then used to forecast the number of coins surviving in circulation and the median lifetime of different denominations. The data are random samples drawn from the coins in circulation at a point in time, the sampled coins being sorted by date of issue.     

用于RBF-SVM参数搜索的伪梯度动态步长算法

针对基于径向基核函数(RBF)的支持向量机(SVM)超参数选择问题,提出了一种基于差分方程的新算法——伪梯度动态步长算法。该算法根据径向基核函数的特点提出由训练集的空间特性确定的核参数搜索范围,并采用对数刻度表示搜索空间;利用参数空间中SVM在两个临近点的分类精度的变化估计参数的搜索方向,并且随着搜索方向的变化动态调整搜索步长,从而实现较快的搜索。通过与Grid和PSO方法的对比实验,表明该算法具有良好的性能。     

新吉坪隧道斜井进正洞挑顶施工技术研究

沪昆铁路客运专线新吉坪隧道所处地质条件复杂,区域地质作用剧烈,碳酸岩分布广泛,不良地质特别发育。针对斜井进正洞施工,提出了纵向爬坡导坑法。并以2#斜井为例,介绍了纵向爬坡导坑法施工工艺和斜井进正洞挑顶施工的控制要点,以及在施工过程中的控制量测方法,为新吉坪隧道斜井进正洞挑顶施工提供了技术指导,为类似工程施工提供参考。     

畜禽垃圾螺旋挤压固液分离机优化设计

针对螺旋挤压机对不同类型畜禽垃圾挤压脱水效果不佳和挤压过程的指标不明确的问题,课题组采用间断螺旋结构对螺旋挤压固液分离机进行优化设计。以压力梯度和出料中水的质量分数作为挤压脱水过程的评价指标,选择螺杆转速、开合行程和入料中水的质量分数为影响因素进行正交实验,探究工艺参数对挤压和脱水效果的影响。结果表明：螺旋挤压脱水过程中对压力梯度影响由大到小为入料中水的质量分数、螺杆转速和开合行程,对出料中水的质量分数影响由大到小为螺杆转速、入料中水的质量分数和开合行程。压力梯度的大小能有效反映挤压过程的挤压和脱水效果,调整螺旋挤压机的螺杆转速和开合行程可适应不同类型的物料;在螺杆转速为25.00 r/min,开合行程为45.00 mm和入料中水的质量分数为84.00%时,螺旋挤压机能实现畜禽垃圾最佳挤压和脱水效果。     

面向智能生产的分布式流水车间调度研究

为了使传统流水车间的调度模型更灵活和更智能化以适应不同生产环境,课题组提出了基于深度学习的分布式流水车间调度方法。通过学习和分析分布式车间系统中的大量数据,利用策略梯度方法在多次迭代优化后使目标得到近似最优解,获取了更智能、适应性更强的生产计划和调度策略;并通过实验和仿真进行验证。结果表明该方法能提高生产效率和资源利用率,并具有成本控制方面的潜力。该研究为制造业的分布式生产环境提供了一种先进的调度策略,为车间管理者提供更准确、更智能的决策参考。     

A New Quantile Function with Applications to Reliability Analysis

In this article, we propose a new class of distributions defined by a quantile function, which nests several distributions as its members. The quantile function proposed here is the sum of the quantile functions of the generalized Pareto and Weibull distributions. Various distributional properties and reliability characteristics of the class are discussed. The estimation of the parameters of the model using L-moments is studied. Finally, we apply the model to a real life dataset.     

近代广东商业人群在广西的分布面及其梯度差考详——粤港商业经济对广西经济辐射研究之二

文章从中国近代史上城镇经济主体——商业经济的角度切入,运用各类历史资料,分区逐县地确证广东商业人群以及所造成的“无东不成市”格局在全广西的分布范围,并揭示其在广西不同地域的程度等差和梯度分布状态。从而,以原始的生活场景原生态地呈现出粤港澳地区对广西经济辐射由东而西逐步推进、由城市而圩市逐层次渗透的基本节奏和客观规律。     

Methods for spatial and temporal land use and land cover assessment for urban ecosystems and application in the greater Baltimore-Chesapeake region

Understanding contemporary urban landscapes requires multiple sets of spatially and temporally compatible data that can integrate historical land use patterns and disturbances to land cover. This paper presents three principal methods: (1) core analysis; (2) historic mapping; and (3) gradient analysis, to link spatial and temporal data for urban ecosystems and applies their use in the Baltimore-Chesapeake region. Paleoecological evidence derived from the geochronology of sediment cores provides data on long-term as well as recent changes in vegetative land cover. This information, combined with contemporary vegetation maps, provides a baseline for conducting trend analyses to evaluate urbanization of the landscape. A 200-year historical land use database created from historical maps, census data, and remotely sensed data provides a spatial framework for investigating human impacts on the region. A geographic information system (GIS) integrates core analyses with historic data on land use change to yield a comprehensive land use and land cover framework and rates of change. These data resources establish the regional foundation for investigating the ecological components of an urban ecosystem. Urban-rural gradient analyses and patch analyses are proposed as the most appropriate methods for studying the urban ecosystem as they link ecological and social patterns and processes for varying degrees of urbanization.     

Adaptive stochastic gradient boosting tree with composite criterion

ABSTRACT

In this paper, we propose an adaptive stochastic gradient boosting tree for classification studies with imbalanced data. The adjustment of cost-sensitivity and the predictive threshold are integrated together with a composite criterion into the original stochastic gradient boosting tree to deal with the issues of the imbalanced data structure. Numerical study shows that the proposed method can significantly enhance the classification accuracy for the minority class with only a small loss in the true negative rate for the majority class. We discuss the relation of the cost-sensitivity to the threshold manipulation using simulations. An illustrative example of the analysis of suboptimal health-state data in traditional Chinese medicine is discussed.