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英文歌曲在大学英语听力教学中的运用 总被引：3，自引：0，他引：3
兴趣是一种巨大的学习动力。英文歌曲赏析作为一种辅助教学手段 ,能够激发学生的学习兴趣 ,提高教学质量。本文分析了英文歌曲在大学英语听力教学中的作用 ,并结合自己的教学实践提出了一些行之有效的方法来激发学生的学习兴趣 相似文献
283.
Demand forecasting performance is subject to the uncertainty underlying the time series an organization is dealing with. There are many approaches that may be used to reduce uncertainty and thus to improve forecasting performance. One intuitively appealing such approach is to aggregate demand in lower‐frequency “time buckets.” The approach under concern is termed to as temporal aggregation, and in this article, we investigate its impact on forecasting performance. We assume that the nonaggregated demand follows either a moving average process of order one or a first‐order autoregressive process and a single exponential smoothing (SES) procedure is used to forecast demand. These demand processes are often encountered in practice and SES is one of the standard estimators used in industry. Theoretical mean‐squared error expressions are derived for the aggregated and nonaggregated demand to contrast the relevant forecasting performances. The theoretical analysis is supported by an extensive numerical investigation and experimentation with an empirical dataset. The results indicate that performance improvements achieved through the aggregation approach are a function of the aggregation level, the smoothing constant, and the process parameters. Valuable insights are offered to practitioners and the article closes with an agenda for further research in this area. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 479–498, 2013 相似文献
284.
Yemane Wolde‐Rufael 《Defence and Peace Economics》2013,24(5):423-436
The aim of this paper is to examine the impact of defence spending and income on the evolution of Ethiopia’s external debt over the period 1970–2005. Using the bounds test approach to cointegration and Granger causality tests, we find a long run and a causal relationship between external debt, defence spending and income. Defence spending had a positive and a significant impact on the stock of external debt while income had a negative and a statistically significant impact on external debt. Our findings suggest that an increase in defence spending contributes to the accumulation of Ethiopia’s external debt, while an increase in economic growth helps Ethiopia to reduce its external debt. 相似文献
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Service systems such as call centers and hospital emergency rooms typically have strongly time‐varying arrival rates. Thus, a nonhomogeneous Poisson process (NHPP) is a natural model for the arrival process in a queueing model for performance analysis. Nevertheless, it is important to perform statistical tests with service system data to confirm that an NHPP is actually appropriate, as emphasized by Brown et al. [8]. They suggested a specific statistical test based on the Kolmogorov–Smirnov (KS) statistic after exploiting the conditional‐uniform (CU) property to transform the NHPP into a sequence of i.i.d. random variables uniformly distributed on [0,1] and then performing a logarithmic transformation of the data. We investigate why it is important to perform the final data transformation and consider what form it should take. We conduct extensive simulation experiments to study the power of these alternative statistical tests. We conclude that the general approach of Brown et al. [8] is excellent, but that an alternative data transformation proposed by Lewis [22], drawing upon Durbin [10], produces a test of an NHPP test with consistently greater power. We also conclude that the KS test after the CU transformation, without any additional data transformation, tends to be best to test against alternative hypotheses that primarily differ from an NHPP only through stochastic and time dependence. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 66–90, 2014 相似文献
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针对深度强化学习在柔性作业车间调度问题上泛化能力不足的问题,提出结合课程学习和深度强化学习的方法。通过动态调整训练实例难度,重点增强最难实例的训练,以适应不同数据分布,避免学习过程中的遗忘问题。仿真测试结果表明,算法在未经训练的大规模问题和基准数据集上保持了不错的性能。在2种人造分布的4个未训练大规模问题上取得了更好的性能表现。相较于精确方法和元启发式方法,对于计算量较大的问题实例,能快速地获得质量不错的解。同时算法可以适应不同的数据分布的柔性作业车间调度问题,具有较快收敛速度和较好泛化能力。 相似文献
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针对有人机动雷达/无人机集群（manned mobile radar/unmanned aerial vehicle cluster,MMR/UAVC）编队指挥控制系统结构设计问题进行了研究。以未来无人机蜂群探测任务为背景,提出MMR/UAVC协同探测作战模式,结合编队组织结构和作战流程,对指挥控制系统总体设计提出具体要求。在此基础上,设计了包括决策规划层、协同控制层和效能评估层的递阶式指挥控制系统结构,概括了各层次主要功能与逻辑关系。对指挥控制系统的关键模块和支撑技术进行了分析。 相似文献
290.
张俊峰;窦长旭;陈企华;张扬 《火力与指挥控制》2023,48(7):115-119
军事标图是军队参谋人员一项重要的指挥技能训练内容。提出基于知识推理和兴趣区域过滤的标图评判方法,用于实现军事标图作业的自动化评判。阐述了知识推理的一般原理,以及针对标图要素的知识表示,分析基于Rete算法的知识推理网络运用;采用兴趣区域过滤的方式,提高评判精准度,阐述标图作业智能化评判的具体实现流程。通过在标图训练系统中的运用,证实了方法的有效性。 相似文献