某水电厂甩负荷保厂用电控制策略优化

针对某水电厂甩负荷后会出现V/Hz限制保护动作,启动紧急事故停机,无法满足机组保厂用电的问题,提出了快速响应和超前预判相结合的方法,利用PID控制系统原理,对开机和甩负荷逻辑进行了改进,使频率低值在响应速度方面理论上得以提高。以优化后的甩负荷控制系统为内容做试验,试验结果避免了V/Hz限制保护动作,所提出的方法对抑制频率超调现象具有普遍适用性。     

广西横县农业灌溉存在问题与对策

针对广西横县农村水利灌溉现状及存在问题,指出横县必须调整农业产业结构,发展节水农业;在搞好水利工程维护,提高水的利用率的同时,采取合理调水、因地制宜配水、改革灌溉制度、加强节水新技术推广应用等对策。     

巡航导弹智能自主在线目标识别选择问题研究

巡航导弹智能自主在线目标识别选择是巡航导弹智能自主作战的重要特征之一.主要针对在巡航导弹弹载计算机计算能力弱、反应时间较短的情况下,如何快速地对目标进行识别分类.采用模板匹配方法进行自动目标识别的大量工作在地面进行,降低了弹载计算机的计算量.为了提高在线智能自主目标识别精度和速度,提出了基于相似度竞争网络,以继承竞争网络在模式识别方面快速简单的优点,同时针对竞争网络抗干扰能力差,对模板类型以外目标无法剔除的不足进行改进,很好解决了巡航导弹在线智能自主目标识别的算法问题.最后通过仿真对算法进行验证.     

煤基富勒烯电子性质和非线性光学性质的密度泛函理论研究

使用基于密度泛函理论的量子化学计算方法对煤基富勒烯进行了研究。重点关注由氮和硅掺杂C₆₀形成的杂化富勒烯结构。计算了这些杂化富勒烯的几何结构、稳定性、电子结构、介电常数和非线性光学性质并与未掺杂富勒烯相比较。研究发现,氮掺杂富勒烯失电子能力增强而硅掺杂富勒烯得电子能力增强。此外,根据计算结果可知掺杂可使富勒烯介电常数增大。对煤基富勒烯的非线性光学性质进行了探讨,发现氮掺杂富勒烯和硅掺杂富勒烯均具有比未掺杂富勒烯明显大的三阶非线性光学系数。     

Finite-time stability analysis of impulsive discrete-time switched systems with nonlinear perturbation

The problem of finite-time stability for a class of discrete-time switched systems in the presence of both non-Lipschitz perturbation and impulse effects is studied in this paper. Based on the average dwell-time approach, a criterion is proposed which ensures that the system’s state trajectory remains in a bounded region of the state space over a pre-specified finite-time interval if we impose a bound on the initial condition. It is shown that the finite-time stability degree could be greater than one, which is quite different from the existing results for asymptotic stability. Moreover, the total activation time of the Schur stable subsystems does not need to be greater than that of the unstable subsystems. A numerical example is presented to illustrate the effectiveness of the proposed design method.     

基于模糊理论的随机需求系统

需求量是供销系统成本优化中的重要指标.目前常见的研究方法是采用泊松分布来拟合.通过数据统计和分析,我们发现采用模糊三角去拟合随机需求量有更好的拟合度和科学性.采用模糊理论对随机需求进行了建模分析,设计了随机需求系统的算法并最终对其进行了实现.     

全业务运营的重要窗口——融合终端

介绍融合终端的发展现状和发展趋势,分析融合终端上开展的典型业务,并着重阐述发展融合终端的几个关键问题,包括融合终端的商业模式、融合终端技术以及融合业务。     

Object recognition using a bio-inspired neuron model with bottom-up and top-down pathways

In this paper, a new artificial neural network model is proposed for visual object recognition, in which the bottom-up, sensory-driven pathway and top-down, expectation-driven pathway are fused in information processing and their corresponding weights are learned based on the fused neuron activities. During the supervised learning process, the target labels are applied to update the bottom-up synaptic weights of the neural network. Meanwhile, the hypotheses generated by the bottom-up pathway produce expectations on sensory inputs through the top-down pathway. The expectations are constrained by the real data from the sensory inputs, which can be used to update the top-down synaptic weights accordingly. To further improve the visual object recognition performance, the multi-scale histograms of oriented gradients (MS-HOG) method is proposed to extract local features of visual objects from images. Extensive experiments on different image datasets demonstrate the efficiency and robustness of the proposed neural network model with features extracted using the MS-HOG method on visual object recognition compared with other state-of-the-art methods.     

基于两种方式的股票时间序列关联的研究

Es-Apriori算法是一个对多元时间序列跨事务关联规则分析的高效处理算法,本文针对当前证券交易市场的特点对此算法的数据预处理部分改了一些改进,加入股票成交量数据项以及二维时间模式两种方式的分析.试验证明,该改进对投资者提供了更为有效的决策支持.     

PLC和电液换向阀在跋山水库调速器改造中的应用

针对水电站水轮机调速器改造中存在的问题，对整改方案进行分析。通过对CT-1500调速器改造，采用以PLC为控制核心和数字式电液换向阀的微机调速器系统，取得了良好的效果。图1幅。