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781.
随着系统规模、芯片功耗和链路速率的提升,高性能互连网络的整体故障率也不断上升,传统运维方式将难以为继,给高性能计算系统整体可靠性和可用性带来了巨大挑战。针对网络端口阻塞这类严重网络故障,提出无监督算法的预测模型。该模型从历史信息中挖掘征兆性规律并形成新的特征向量,应用K-means聚类算法对特征向量进行学习归类。在预测时,结合端口当前状态,利用二次指数平滑算法对未来状态进行预测,将得到的新特征向量使用K-means算法预判是否会发生阻塞故障。利用拓扑结构信息,分别对叶交换机和根交换机构建预测子模型,进而提升预测的精确率。结果表明,该预测模型能保持在召回率为88.2%的前提下,达到65.2%的准确率,可为运维人员提供有效的辅助。  相似文献   
782.
《防务技术》2022,18(11):2083-2096
Ground military target recognition plays a crucial role in unmanned equipment and grasping the battlefield dynamics for military applications, but is disturbed by low-resolution and noisy-representation. In this paper, a recognition method, involving a novel visual attention mechanism-based Gabor region proposal sub-network (Gabor RPN) and improved refinement generative adversarial sub-network (GAN), is proposed. Novel central–peripheral rivalry 3D color Gabor filters are proposed to simulate retinal structures and taken as feature extraction convolutional kernels in low-level layer to improve the recognition accuracy and framework training efficiency in Gabor RPN. Improved refinement GAN is used to solve the problem of blurry target classification, involving a generator to directly generate large high-resolution images from small blurry ones and a discriminator to distinguish not only real images vs. fake images but also the class of targets. A special recognition dataset for ground military target, named Ground Military Target Dataset (GMTD), is constructed. Experiments performed on the GMTD dataset effectively demonstrate that our method can achieve better energy-saving and recognition results when low-resolution and noisy-representation targets are involved, thus ensuring this algorithm a good engineering application prospect.  相似文献   
783.
《防务技术》2022,18(9):1513-1522
It is important to understand how ballistic materials respond to impact from projectiles such that informed decisions can be made in the design process of protective armour systems. Ballistic testing is a standards-based process where materials are tested to determine whether they meet protection, safety and performance criteria. For the V50 ballistic test, projectiles are fired at different velocities to determine a key design parameter known as the ballistic limit velocity (BLV), the velocity above which projectiles perforate the target. These tests, however, are destructive by nature and as such there can be considerable associated costs, especially when studying complex armour materials and systems. This study proposes a unique solution to the problem using a recent class of machine learning system known as the Generative Adversarial Network (GAN). The GAN can be used to generate new ballistic samples as opposed to performing additional destructive experiments. A GAN network architecture is tested and trained on three different ballistic data sets, and their performance is compared. The trained networks were able to successfully produce ballistic curves with an overall RMSE of between 10 and 20 % and predicted the V50 BLV in each case with an error of less than 5 %. The results demonstrate that it is possible to train generative networks on a limited number of ballistic samples and use the trained network to generate many new samples representative of the data that it was trained on. The paper spotlights the benefits that generative networks can bring to ballistic applications and provides an alternative to expensive testing during the early stages of the design process.  相似文献   
784.
在英语课堂教学中运用英文电影,可为学生提供丰富的语境化的语言和真实的跨文化信息,为学生创造在课堂上实践语言的机会,也更能激发学生的英语学习兴趣。分析在非英语专业学生课堂教学中选择英文电影的标准,探讨电影观前、观看和观后三个阶段的教学活动。  相似文献   
785.
外语交际能力是社会所需高水平复合应用型人才应具备的素养。本研究考察真实性语言应用实践活动对非英语专业大学生外语交际策略和听说能力的影响。通过对比研究发现,学生参加了真实性语言应用实践活动后,其交际策略使用情况得到改善,更倾向于使用积极交际策略,消极策略的使用频率明显减少;听说水平整体得到提高;寻找机会说英语的主动性增强。因此,真实性语言应用实践活动有助于大学生提高外语交际能力,提高社会所需整体应用能力素养。  相似文献   
786.
探究性学习的实质是要求教师转变教育观念,在教学中充分调动学生学习的主动性和积极性,激发学生学习的主人翁意识,真正使学生成为学习的主人。因此高中政治课的课堂教学应该充分渗透探究性学习的精神,同时教师又应在这一宗旨的指导下,根据教材的内容和特点的不同采用不同的模式,选用不同的方法,这样才能达到构建高效课堂的目的。  相似文献   
787.
目前,对供应链库存风险损失的定量研究比较少,而定量研究中鲜有对风险偏好变化问题的研究,因此首先分析了各种风险度量方法,通过比较采用了险度函数作为对装备供应链风险损失的度量方法;然后,结合装备供应链实际,提出了定常风险偏好特性险度函数和可变风险偏好特性险度函数的适用范围,以及装备供应链库存风险损失度量的损失水平值,并给出了装备供应链库存风险损失度量函数;最后,通过算例进行了验证.实验结果表明:行为人的不同风险偏好特性会对同一事态产生不同的预判,进而可能影响对风险的决策,这是符合客观现实的.  相似文献   
788.
We consider two regression models: linear and logistic. The dependent variable is observed periodically and in each period a Bayesian formulation is used to generate updated forecasts of the dependent variable as new data is observed. One would expect that including new data in the Bayesian updates results in improved forecasts over not including the new data. Our findings indicate that this is not always true. We show there exists a subset of the independent variable space that we call the “region of no learning.” If the independent variable values for a given period in the future are in this region, then the forecast does not change with any new data. Moreover, if the independent variable values are in a neighborhood of the region of no learning, then there may be little benefit to wait for the new data and update the forecast. We propose a statistical approach to characterize this neighborhood which we call the “region of little learning.” Our results provide insights into the trade‐offs that exist in situations when the decision maker has an incentive to make an early decision based on an early forecast versus waiting to make a later decision based on an updated forecast. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 532–548, 2014  相似文献   
789.
The strategic defense initiative (SDI) intends to renew the leadership of the USA on the western alliance. The initiative takes place in a period when a summation technology prevails for the aggregation of contributions of NATO allies. We investigate if SDI induces a shift in Hirshleifer’s social composition function. Panel data tests over the period 1970–1990 do not confirm any break toward a best-shot aggregator. SDI does not alter the core of deterrence. It is indeed a public good at the US level but not at the NATO level, where, it is one of the joint products of the alliance. We also investigate the lessons to be drawn for the current debates on ballistic defense.  相似文献   
790.
陆军作战仿真是一个复杂的系统工程,仿真所涉及的模型种类繁多、类别不一。针对当前陆军作战仿真模型开发不规范、通用性与可重用性差、开发和集成效率低的现状,在对陆军作战仿真模型构成要素进行分析和归纳的基础上,提出仿真模型组件化设计的建模方法、采用"方案-单元-实体-组件"方式的模型管理机制以及采用事件驱动、事件订购和分发方式的模型交互机制。  相似文献   
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