北洺河铁矿地表及岩层移动观测系统研究

地表塌陷严重威胁着矿山安全生产,破坏地表生念环境。为了全面系统地研究地表塌陷和岩层移动问题,获得准确可靠的监测资料,不但要在地表布设测点,还要住岩层内部布设测点,从地表和岩层内部2个方面着手建迂岩移观测系统,为后期研究地表及岩层的移动和变形规律做好准备工作。     

植物写生中的感观分析

从植物写生的要求和特点出发,在吸收传统理论知识的基础上,针对写生过程中观察生活、培养想象、加强艺术修养等各个环节作了探讨,从而使创造性的研究和运用在写生实践中得以更好的展现和发挥.     

流光放电等离子体烟气脱硫监测系统的设计

流光放电等离子体烟气脱硫系统是一套符合我国环境治理要求的装置,为保证脱硫系统安全、经济、稳定、高效运行,对其配套的监测系统装置的研究也是很重要的.本文以CAN总线的集散型控制系统为中心,主要介绍了监测系统的CAN适配卡的软硬件设计以及监测界面的开发.     

基于ibdump的InfiniBand网络拥塞控制观测方法研究

在InfiniBand(IB)体系网络中,拥塞控制(Congestion Control,CC)能够确保高性能和资源利用率,避免拥塞传播对于无辜流的性能损害。首先分析IB网络采用的ECN(Explicit Congestion Notification)拥塞控制机制,然后提出一种集中控制的多点流量发生器CTBG(Central Traffic Behavior Generator),它提供了对流量的统计能力。为了进一步剖析IB网络拥塞控制的细粒度行为,提出了基于ibdump和wireshark的观测方法。实验表明,提出的测量机制能够细粒度、低开销地观测IB网络的拥塞控制行为,其对拥塞控制机制的研究具有重要的指导意义。     

基于短时谱相估计改进型减谱法语音降噪研究

针对手机等移动智能终端设备的降噪问题,通过对基本减谱法的分析研究发现其在使用中存在不足,对基本减谱法进行了功率谱修正和输入幅值谱自适应的改进,通过调节噪声系数α和功率谱系数β以提高语言处理的灵活性以及输出信号的信噪比。仿真实验对比了基本减谱法与改进减谱法对含噪语音的处理效果,结果表明改进减谱法对含噪语音的降噪效果更为明显。     

Sensemaking in military planning: a methodological study of command teams

Sensemaking, understanding how to deal with the situation at hand, has a central role in military command. This paper presents a method for measuring sensemaking performance in command teams during military planning. The method was tested in two experiments with Army captains serving as participants. The task was to produce parts of a brigade order within 6 h. The participants worked in teams of 5–7 individuals, 16 teams in the first experiment and 8 teams in the second experiment, with one team member acting as brigade commander. The independent variables were amount of information and type of communication, respectively. The characteristics of each team’s sensemaking process were assessed from video recordings of their planning sessions. The quality of their plans was judged by military experts. Although plan quality was unaffected by the experimental manipulations, the quality of the sensemaking process was related to the quality of the plans.

An estimate on the convergence of MKZ–Bézier operators

The pointwise approximation properties of the MKZ–Bézier operators M_n,α(f,x) for α≥1 have been studied in [X.M. Zeng, Rates of approximation of bounded variation functions by two generalized Meyer–König–Zeller type operators, Comput. Math. Appl. 39 (2000) 1–13]. The aim of this paper is to study the pointwise approximation of the operators M_n,α(f,x) for the other case 0<α<1. By means of some new estimate techniques and a result of Guo and Qi [S. Guo, Q. Qi, The moments for the Meyer–König and Zeller operators, Appl. Math. Lett. 20 (2007) 719–722], we establish an estimate formula on the rate of convergence of the operators M_n,α(f,x) for the case 0<α<1.     

Unsupervised named-entity extraction from the Web: An experimental study

The KnowItAll system aims to automate the tedious process of extracting large collections of facts (e.g., names of scientists or politicians) from the Web in an unsupervised, domain-independent, and scalable manner. The paper presents an overview of KnowItAll's novel architecture and design principles, emphasizing its distinctive ability to extract information without any hand-labeled training examples. In its first major run, KnowItAll extracted over 50,000 class instances, but suggested a challenge: How can we improve KnowItAll's recall and extraction rate without sacrificing precision?This paper presents three distinct ways to address this challenge and evaluates their performance. Pattern Learning learns domain-specific extraction rules, which enable additional extractions. Subclass Extraction automatically identifies sub-classes in order to boost recall (e.g., “chemist” and “biologist” are identified as sub-classes of “scientist”). List Extraction locates lists of class instances, learns a “wrapper” for each list, and extracts elements of each list. Since each method bootstraps from KnowItAll's domain-independent methods, the methods also obviate hand-labeled training examples. The paper reports on experiments, focused on building lists of named entities, that measure the relative efficacy of each method and demonstrate their synergy. In concert, our methods gave KnowItAll a 4-fold to 8-fold increase in recall at precision of 0.90, and discovered over 10,000 cities missing from the Tipster Gazetteer.     

杯式风速传感器计量的线性研究

线性是表征杯式风速传感器角速度与风速正比关系的重要计量性能指标.传感器动态运行时,它能直接反映风杯结构设计特征,并产生风速输出值的系统误差,其技术指标要求不超过±0.5 m/s.目前,风速计量用"示值误差"表示测量结果,不能直接反映传感器的线性特征.根据检定规程的测量方法,对风速传感器在风洞中开展全量程重复性测量并获取...     

散射辐射组合系统对造波水面的观测研究

介绍了新研制的Ｘ波段散射计组合系统。利用这一组系统进行了同时同地相继观测，得到ｖｗ，ｈｈ，ｈｖ多极化的后向散射系数σ＾０ＰＱ（ｐ，ｑ－ｖ，ｈ），ｖ和ｈ极化的辐射亮温度ＴＢＰ（ｐ＝ｖ，ｈ）。为模拟海面风场驱动起伏海面，利用室内人工造波池，在机械驱动下产生给定波谱的随机性或周期性起伏水面。用该散射计地组合系统观测多角度与多种起伏高度时的σ＾０ｐｑ－ＴＢｐ。并用双尺度随机粗糙面散射辐射理论模，烽值地模拟