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1.
Air travelers can carry an infectious disease's pathogenic microorganism in their bodies and spread the disease from one country to another in a few days. To delay the spread, health screening stations may be set up at airport terminals to screen travelers. This research tested three different health screening strategies, each with a different combination of screening stations at trip origins, destinations and connecting airports. Discrete event simulations were performed, based on the 2014 to 2016 Ebola virus epidemic, with special focus on travelers from the West African countries traveling to the United States, including travelers who transferred flights at airports in European Union member states. The effectiveness of the screening strategies was analyzed in terms of correct detection, missed detection and false alarm rate. The results showed that exit screening at trip origins brought big improvements in the performance measurements compared to no screening. However, additional screening at the destinations and connecting airports contributed marginal benefits. 相似文献
2.
本文通过调整迭代解码过程中系统位接收值的加权系数,提出了一种Turbo码加权迭代解码算法。该算法改变了迭代运算后Turbo码解码器输出软值中系统位接收值信息和它的外部估计信息的比重,使Turbo码无论在低信噪比或是在高信噪比时均具有优良的纠错性能。仿真结果显示,采用Turbo码加权迭代解码算法,不仅能提高Turbo码的收敛速度,而且能进一步降低Turbo码解码时的地板值,使Turbo码的比特误码率在高、低信噪比时都能够得到进一步改善。 相似文献
3.
本文介绍了进步频率高距离分辨率信号,分析了运动速度对该高距离分辨率信号的影响,提出了基于多散射中心联合检测(M/N检测)的速度环路补偿方案。该方案使用多距离单元的联合检测完成高距离分辨率信号的最佳速率补偿,同时进一步降低目标的虚警概率,提高了目标的发现概率。 相似文献
4.
离子色谱是高效液相色谱法当中的一类,又被称之为现代离子色谱。作为一种高效科学的检测方法,离子色谱发展迅速,被广泛用于大气、土壤和水质检测中。本文主要综述了离子色谱法应用于生活饮用水检测的研究进展。 相似文献
5.
《International Journal of Forecasting》2020,36(3):800-813
We develop an iterative and efficient information-theoretic estimator for forecasting interval-valued data, and use our estimator to forecast the SP500 returns up to five days ahead using moving windows. Our forecasts are based on 13 years of data. We show that our estimator is superior to its competitors under all of the common criteria that are used to evaluate forecasts of interval data. Our approach differs from other methods that are used to forecast interval data in two major ways. First, rather than applying the more traditional methods that use only certain moments of the intervals in the estimation process, our estimator uses the complete sample information. Second, our method simultaneously selects the model (or models) and infers the model’s parameters. It is an iterative approach that imposes minimal structure and statistical assumptions. 相似文献
6.
In this paper, we propose a method for improving the accuracy of the estimation of interregional input–output tables, by combining the RAS method and the real-coded Genetic Algorithm (GA); these are simple representative methods for the estimation of an interregional input–output table. By comparing the performance evaluation results obtained using the proposed method, the RAS method, and Simulated Annealing, we verified that the combination of the genetic algorithm and the RAS method can enhance the estimation accuracy of an interregional input–output table. In addition, performance is further enhanced by adjusting GA parameters. 相似文献
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8.
Frances Homans 《Ecological Economics》2011,70(6):1129-1138
We model optimal detection of sub-populations of invasive species that establish ahead of an advancing front. For many invaders, eradication of the main population is an untenable goal, yet it may be possible to treat and eradicate emerging sub-populations once these sub-populations are detected. We embed a dynamically optimal post-detection management plan of sub-populations into a model of optimal detection effort determination and find that optimal detection effort depends, in part, on the distance from the main front: locations closer to the front with shorter management horizons enjoy lower reductions in overall cost from intervention. The uninfested landscape is divided into two zones, characterized by different dynamically optimal management plans: a suppression zone and an eradication zone. In the suppression zone, optimal detection effort increases with distance from the front. At the distance where the suppression zone yields to the eradication zone, optimal detection effort plateaus at its maximum level. 相似文献
9.
<正> 我国是一个人口众多,人均资源相对贫乏,经济、文化比较落后的发展中国家。要在这样的国家实现科学技术的现代化,建设一个现代化的工业强国,依赖外国不行,闭关自守也不行。坚持自力更生为主,积极吸收国外科学技 相似文献
10.
对于在建建筑的规划管控,是一个城市规划管理局的重要职能,由于在建建筑众多,尤其对于一些大型城市,对于在建建筑的规划管控主要是从建筑物的尺寸角度来进行的,包括是否超宽、超高等。如何引入计算机数学思想,构建一个在建建筑的智能化规划监察管控系统,并杜绝人情因素,成为提升规划监察工作效率和质量,体现科学发展观的重要技术手段。 相似文献