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1.
Emergency material allocation is an important part of postdisaster emergency logistics that is significant for improving rescue effectiveness and reducing disaster losses. However, the traditional single‐period allocation model often causes local surpluses or shortages and high cost, and prevents the system from achieving an equitable or optimal multiperiod allocation. To achieve equitable allocation of emergency materials in the case of serious shortages relative to the demand by victims, this article introduces a multiperiod model for allocation of emergency materials to multiple affected locations (using an exponential utility function to reflect the disutility loss due to material shortfalls), and illustrates the relationship between equity of allocations and the cost of emergency response. Finally, numerical examples are presented to demonstrate both the feasibility and the usefulness of the proposed model for achieving multiperiod equitable allocation of emergency material among multiple disaster locations. The results indicate that the introduction of a nonlinear utility function to reflect the disutility of large shortfalls can make the material allocation fairer, and minimize large losses due to shortfalls. We found that achieving equity has a significant but not unreasonable impact on emergency costs. We also illustrate that using differing utility functions for different types of materials adds an important dimension of flexibility. 相似文献
2.
A. M. Abd El-Raheem 《Journal of Statistical Computation and Simulation》2019,89(16):3075-3104
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion. 相似文献
3.
Random effects regression mixture models are a way to classify longitudinal data (or trajectories) having possibly varying lengths. The mixture structure of the traditional random effects regression mixture model arises through the distribution of the random regression coefficients, which is assumed to be a mixture of multivariate normals. An extension of this standard model is presented that accounts for various levels of heterogeneity among the trajectories, depending on their assumed error structure. A standard likelihood ratio test is presented for testing this error structure assumption. Full details of an expectation-conditional maximization algorithm for maximum likelihood estimation are also presented. This model is used to analyze data from an infant habituation experiment, where it is desirable to assess whether infants comprise different populations in terms of their habituation time. 相似文献
4.
李可风 《太原师范学院学报(社会科学版)》2002,(4)
作家的人格是其作品风格的内在因素 ,往往决定着其作品的风格。我们在研究作品风格的时候 ,不能不关注作家的人格。只有对作家的人格进行全面深入的审视 ,才能更准确地理解和把握其作品的风格。探讨陶渊明的人格魅力及其特征 ,是深入研究陶渊明作品风格的至关重要的途径。从陶渊明的作品中 ,从他的言行中 ,我们可以领悟到他的情趣和胸襟 ,领悟到一种具体的人格。陶渊明自然率真平和旷达的个性特征构筑了他的诗化人格 ,即未经世俗异化的高尚贞洁的人格。这种人格的内在思想根源是自然化迁的宇宙观和委运自然的人生观。这种人格的外在表现形式是他任真自得和固穷守节的行为方式。他的作品中常见的酒与菊、孤松、孤云与归鸟等艺术形象组成了陶渊明诗化人格的象征系列 相似文献
5.
针对高损耗介质材料电磁参数的宽频带测试问题,提出了利用脊波导进行测试的新方法,建立了电磁参数测试系统,并采用TRL技术进行了系统校准。该方法仅用3个波段的脊波导即可覆盖2.0~18.0GHz宽频带范围内的电磁参数测试,具有频带宽、体积小、测试精确度高等优点。 相似文献
6.
论创新思维的基础 总被引:4,自引:0,他引:4
蒋笃运 《郑州大学学报(哲学社会科学版)》2002,35(3):58-61
创新是人类的本质特征 ,在人类创新的实践中 ,创新思维具有基础性和先导性的作用 ,是理论创新、科技创新、体制创新的基础和前提。创新思维是唯物辩证法的基本原理与规律在思维过程中的具体运用和体现 ,是多种思维要素相互协调作用的结果 ,它有着坚实的物质基础、心理基础和方法论基础 相似文献
7.
曹俊艳 《河北理工大学学报(社会科学版)》2002,2(Z1):173-175
多媒体技术有利于开发人的潜能,提高教学质量,培养学生的广泛兴趣,有利于加强德育教育.素质教育需要多媒体技术,需要掌握多媒体技术的教师.造就一支具有创新意识、创新精神、创新能力的高素质教师队伍,是全面落实素质教育的根本保证. 相似文献
8.
讨论了充分利用C4 0的硬件并行结构进行实数FFT的并行算法 ,并在地震勘探信号处理中得以应用 相似文献
9.
建立高效的高校物流体系 总被引:2,自引:0,他引:2
将经济领域的物流引入高校,提出了高校物流体系概念;介绍了高校物流的组成要素及物流目标。为了增加高校在市场环境中的适应性及竞争能力,首先应提高物流系统中的管理水平,从整合、优化、预测的角度制定适应新形势下的物流战略。 相似文献
10.
Amy H. Herring Joseph G. Ibrahim Stuart R. Lipsitz 《Journal of the Royal Statistical Society. Series C, Applied statistics》2004,53(2):293-310
Summary. Non-ignorable missing data, a serious problem in both clinical trials and observational studies, can lead to biased inferences. Quality-of-life measures have become increasingly popular in clinical trials. However, these measures are often incompletely observed, and investigators may suspect that missing quality-of-life data are likely to be non-ignorable. Although several recent references have addressed missing covariates in survival analysis, they all required the assumption that missingness is at random or that all covariates are discrete. We present a method for estimating the parameters in the Cox proportional hazards model when missing covariates may be non-ignorable and continuous or discrete. Our method is useful in reducing the bias and improving efficiency in the presence of missing data. The methodology clearly specifies assumptions about the missing data mechanism and, through sensitivity analysis, helps investigators to understand the potential effect of missing data on study results. 相似文献