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61.
A ship that is not under control (NUC) is a typical incident that poses serious problems when in confined waters close to shore. The emergency response to NUC ships is to select the best risk control options, which is a challenge in restricted conditions (e.g., time limitation, resource constraint, and information asymmetry), particularly in inland waterway transportation. To enable a quick and effective response, this article develops a three‐stage decision‐making framework for NUC ship handling. The core of this method is (1) to propose feasible options for each involved entity (e.g., maritime safety administration, NUC ship, and ships passing by) under resource constraint in the first stage, (2) to select the most feasible options by comparing the similarity of the new case and existing cases in the second stage, and (3) to make decisions considering the cooperation between the involved organizations by using a developed Bayesian network in the third stage. Consequently, this work provides a useful tool to achieve well‐organized management of NUC ships.  相似文献   
62.
Longitudinal categorical data are commonly applied in a variety of fields and are frequently analyzed by generalized estimating equation (GEE) method. Prior to making further inference based on the GEE model, the assessment of model fit is crucial. Graphical techniques have long been in widespread use for assessing the model adequacy. We develop alternative graphical approaches utilizing plots of marginal model-checking condition and local mean deviance to assess the GEE model with logit link for longitudinal binary responses. The applications of the proposed procedures are illustrated through two longitudinal binary datasets.  相似文献   
63.
用白噪声信号作为输入信号对钻柱系统脉冲响应进行辨识。研究了伪随机信号的特征及伪随机信号产生的方法,得出了用伪随机信号代替白噪声信号辨识钻柱系统脉冲响应的结论。结合输入信号和输出信号,利用钻柱系统的脉冲响应,讨论了钻柱的临界转速、钻柱共振、钻柱与井壁之间的相互作用、所钻地层岩性等钻井工程问题。  相似文献   
64.
The effect of bioaerosol size was incorporated into predictive dose‐response models for the effects of inhaled aerosols of Francisella tularensis (the causative agent of tularemia) on rhesus monkeys and guinea pigs with bioaerosol diameters ranging between 1.0 and 24 μm. Aerosol‐size‐dependent models were formulated as modification of the exponential and β‐Poisson dose‐response models and model parameters were estimated using maximum likelihood methods and multiple data sets of quantal dose‐response data for which aerosol sizes of inhaled doses were known. Analysis of F. tularensis dose‐response data was best fit by an exponential dose‐response model with a power function including the particle diameter size substituting for the rate parameter k scaling the applied dose. There were differences in the pathogen's aerosol‐size‐dependence equation and models that better represent the observed dose‐response results than the estimate derived from applying the model developed by the International Commission on Radiological Protection (ICRP, 1994) that relies on differential regional lung deposition for human particle exposure.  相似文献   
65.
The components of a reliability system subjected to a common random environment usually have dependent lifetimes. This paper studies the stochastic properties of such a system with lifetimes of the components following multivariate frailty models and multivariate mixed proportional reversed hazard rate (PRHR) models, respectively. Through doing stochastic comparison, we devote to throwing a new light on how the random environment affects the number of working components of a reliability system and on assessing the performance of a k-out-of-n system.  相似文献   
66.
在工程防沙设计中,阻沙率和输沙强度均是确定防护类型及其宽度的重要指标。从工程实际出发,结合典型地形特征,运用实测的阻沙率指标,优化沙漠公路高大沙丘段防沙体系的设计,用理论指导实践的同时,并在实践施工中加以较好地运用,从实践效果上,以阻沙率这一风沙物理指标为依据,确定高大沙丘段的防沙设计参数,是符合实际和可行的方法。  相似文献   
67.
Abstract

A central objective of empirical research on treatment response is to inform treatment choice. Unfortunately, researchers commonly use concepts of statistical inference whose foundations are distant from the problem of treatment choice. It has been particularly common to use hypothesis tests to compare treatments. Wald’s development of statistical decision theory provides a coherent frequentist framework for use of sample data on treatment response to make treatment decisions. A body of recent research applies statistical decision theory to characterize uniformly satisfactory treatment choices, in the sense of maximum loss relative to optimal decisions (also known as maximum regret). This article describes the basic ideas and findings, which provide an appealing practical alternative to use of hypothesis tests. For simplicity, the article focuses on medical treatment with evidence from classical randomized clinical trials. The ideas apply generally, encompassing use of observational data and treatment choice in nonmedical contexts.  相似文献   
68.
The American Red Cross is the most active nonprofit organization involved in disaster planning and response in the United States. The organization deployed nearly 50,000 volunteers to provide essential support to victims of some 125,000 domestic disasters, including home fires, hurricanes, wildfires, and floods, in a recent two‐year period. This study asks how American Red Cross disaster response volunteer experiences function to cultivate satisfaction and, at the other end of the spectrum, the kind of dissatisfaction that leads people to quit; it pays particular attention to ways in which volunteer management shapes dissatisfaction and fatigue because of implications for volunteer retention. Paradoxically, the Red Cross facilitates the highly satisfying act of helping victims, but volunteers feel dissatisfied when management practices get in the way of helping. The study suggests voluntary organizations that rely on skilled, long‐term volunteers to deliver services should evaluate and strengthen their communication strategies, recognition practices, and support systems for volunteers in distress.  相似文献   
69.
Xiong Cai  Yiying Zhang 《Statistics》2017,51(3):615-626
In this paper, we compare the hazard rate functions of the second-order statistics arising from two sets of independent multiple-outlier proportional hazard rates (PHR) samples. It is proved that the submajorization order between the sample size vectors together with the supermajorization order between the hazard rate vectors imply the hazard rate ordering between the corresponding second-order statistics from multiple-outlier PHR random variables. The results established here provide theoretical guidance both for the winner's price for the bid in the second-price reverse auction in auction theory and fail-safe system design in reliability. Some numerical examples are also provided for illustration.  相似文献   
70.
ABSTRACT

Stress-related conditions such as burnout and post-traumatic stress disorder are a growing concern in the humanitarian sector. Aid workers themselves report not only that mental health problems are common, but that the support they receive from their employers is insufficient. Problematically, the experience of the international aid worker – particularly those who are white and from the global North – is often foregrounded in explaining what constitutes stress and related mental health problems. This indicates a wider problem of what is required of ‘the perfect humanitarian’ – a personality that is gendered and racialised – and how this influences the different experiences and treatment of national and international staff from aid agencies. This article explores the organisational culture and working conditions of humanitarian settings and their impact on the mental health and well-being of staff. It argues that there is a structural dimension to stress that is less to do with external security threats and more to do with the specific infrastructure, policies, and practices of humanitarian operations, with implications for aid workers which cut across dimensions of race, gender, and nationality.  相似文献   
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