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121.
本文全面介绍了一种采用改进的SEVQ匹配算法的特定人汉语语音识别系统,具体描述了系统总体方案、系统参数的选取策略、各种识别预处理所用方法及语音模式匹配原理和方法。系统的实时识别率超过93% 相似文献
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研究利用神经网络实现超分辨雷达成像。该方法首先根据Tuff的前后向线性预测(FBLP)方程用神经网络得到样本序列的AR模型参数,然后利用神经网络作线性预测外推,再用神经网络对外推后的数据作离散哈特来变换(DHT)。从哈特来变换可以方便地得到外推数据的离散傅里叶变换,从而得到距离-多普勒超分辨雷达像。利用微波暗室数据对这一方法进行了数字仿真,结果表明这种方法是可行的,即使在低信噪比下也有较好的性能。 相似文献
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Integrated scheduling of loading and transportation with tractors and semitrailers separated 下载免费PDF全文
Motivated by some practical applications, we study a new integrated loading and transportation scheduling problem. Given a set of jobs, a single crane is available to load jobs, one by one, onto semitrailers with a given capacity. Loaded semitrailers are assigned to tractors for transportation tasks. Subject to limited resources (crane, semitrailers, and tractors), the problem is to determine (1) an assignment of jobs to semitrailers for loading tasks, (2) a sequence for the crane to load jobs onto semitrailers, (3) an assignment of loaded semitrailers to tractors for transportation tasks, and (4) a transportation schedule of assigned tractors such that the completion time of the last transportation task is minimized. We first formulate the problem as a mixed integer linear programming model (MILPM) and prove that the problem is strongly NP‐hard. Then, optimality properties are provided which are useful in establishing an improved MILPM and designing solution algorithms. We develop a constructive heuristic, two LP‐based heuristics, and a recovering beam search heuristic to solve this problem. An improved procedure for solutions by heuristics is also presented. Furthermore, two branch‐and‐bound (B&B) algorithms with two different lower bounds are developed to solve the problem to optimality. Finally, computational experiments using both real data and randomly generated data demonstrate that our heuristics are highly efficient and effective. In terms of computational time and the number of instances solved to optimality in a time limit, the B&B algorithms are better than solving the MILPM. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 416–433, 2015 相似文献
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In this article, we study item shuffling (IS) problems arising in the logistics system of steel production. An IS problem here is to optimize shuffling operations needed in retrieving a sequence of steel items from a warehouse served by a crane. There are two types of such problems, plate shuffling problems (PSP) and coil shuffling problems (CSP), considering the item shapes. The PSP is modeled as a container storage location assignment problem. For CSP, a novel linear integer programming model is formulated considering the practical stacking and shuffling features. Several valid inequalities are constructed to accelerate the solving of the models. Some properties of optimal solutions of PSP and CSP are also derived. Because of the strong NP‐hardness of the problems, we consider some special cases of them and propose polynomial time algorithms to obtain optimal solutions for these cases. A greedy heuristic is proposed to solve the general problems and its worst‐case performances on both PSP and CSP are analyzed. A tabu search (TS) method with a tabu list of variable length is proposed to further improve the heuristic solutions. Without considering the crane traveling distance, we then construct a rolling variable horizon heuristic for the problems. Numerical experiments show that the proposed heuristic algorithms and the TS method are effective. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献
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Qiang Zhou Hu-guang He San-feng Liu Xiao-shuo Chen Ze-xun Tang Yang Liu Zhen-yu Qiu Sen-sen Li He Wang Yin-zhi Zhou Jian-nan Zhou Hua-lin Fan Feng-nian Jin 《防务技术》2021,17(2):512-530
To improve corrosion-resistance of shallow-buried concrete urban utility tunnels(UUTs),basalt fiber reinforced polymer(BFRP)bars are applied to reinforce UUTs.As the UUT must have excellent survival capability under accidental explosions,a shallow-buried BFRP bars reinforced UUT(BBRU)was designed and constructed.Repetitive blast experiments were carried out on this BBRU.Dynamic responses,damage evolutions and failure styles of the BBRU under repetitive explosions were revealed.The tunnel roof is the most vulnerable component and longitudinal cracks develop along the tunnel.When the scaled distance is larger than 1.10 m/kg1/3,no cracks are observed in the experiments.When the BBRU is severely damaged,there are five cracks forming and developing along the roof.The roof is simplified as a clamped-supported one-way slab,proved by the observation that the maximum strain of the transverse bar is much larger than that of the longitudinal bar.Dynamic responses of the roof slab are predicted by dynamic Euler beam theory,which can consistently predict the roof displacement under large-scaled-distance explosion.Compared with the UUT reinforced with steel bars,the BBRU has advantages in blast resistance with smaller deflections and more evenly-distributed cracks when the scaled distance is smaller than 1.260 m/kg1/3 and the steel bars enter plastic state.Longer elastic defamation of the BFRP bars endows the UUT more excellent blast resistance under small-scaled-distance explosions. 相似文献
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唐志龙 《军队政工理论研究》2001,2(2):32-34
在思想政治工作实践中 ,作为重要的非理性思维因素在工作主体的思维方式中是大量存在的 ,并且可以“配合”理性思维 ,促进思想政治工作的有效运行。本文分析了形象思维在工作主体思维方式中的地位 ,阐述了在思想政治工作中形象思维的过程、特征及其积极意义与作用 相似文献
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全国解放战争时期,东北战场最先揭开战略反攻序幕,民主联军从吉林以东、长春以西、郑家屯以北、梅河口以南及辽南、热西、冀东等七个重点方向上同时发动进攻,其势如潮涌,纵横关内外。大战结果,民主联军于战略上贯通南北满,一举扭转东北战局,开始掌握战场主动权,迫使东北国民党军转入战略防御,有力地支援了关内战场作战。 相似文献
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唐志龙 《军队政工理论研究》2009,10(5)
社会主义核心价值体系要在实践中真正成为人民群众的行动指南,必须努力开拓其现实化的具体途径.坚持社会主义核心价值体系的科学引领力,可以筑牢当代革命军人核心价值观培育的思想道德基础;发挥当代革命军人核心价值观的巨大推动力,可以拓展社会主义核心价值体系建设的崭新生长点;注重"二力"并发,对促进中华民族共有精神家园建设具有重要价值. 相似文献