结合MSCRs与MSERs的自然场景文本检测

目的 目前,基于MSERs(maximally stable extremal regions)的文本检测方法是自然场景图像文本检测的主流方法。但是自然场景图像中部分文本的背景复杂多变,MSERs算法无法将其准确提取出来,降低了该类方法的鲁棒性。本文针对自然场景图像文本背景复杂多变的特点,将MSCRs(maximally stable color regions)算法用于自然场景文本检测,提出一种结合MSCRs与MSERs的自然场景文本检测方法。方法 首先采用MSCRs算法与MSERs算法提取候选字符区域;然后利用候选字符区域的纹理特征训练随机森林字符分类器,对候选字符区域进行分类,从而得到字符区域;最后,依据字符区域的彩色一致性和几何邻接关系对字符进行合并,得到最终文本检测结果。结果 本文方法在ICDAR 2013上的召回率、准确率和F值分别为71.9%、84.1%和77.5%,相对于其他方法的召回率和F值均有所提高。结论 本文方法对自然场景图像文本检测具有较强的鲁棒性,实验结果验证了本文方法的有效性。     

Stability radius of implicit dynamic equations with constant coefficients on time scales

This paper deals with the stability radii of implicit dynamic equations on time scales when the structured perturbations act on both the coefficient of derivative and the right-hand side. Formulas of the stability radii are derived as a unification and generalization of some previous results. A special case where the real stability radius and the complex stability radius are equal is studied. Examples are derived to illustrate results.     

Estimation of the Bivariate Stable Spectral Representation by theProjection Method

A method of estimating the spectral representation of a generalized bivariatestable distribution is presented, based on a series of maximum likelihood (ML)estimates of the stable parameters of univariate projections of the data. Thecorresponding stable spectral density is obtained by solving a quadraticprogram. The proposed method avoids the often arduous task of computing themultivariate stable density, relying instead on the standard univariate stabledensity. The paper applies this projection procedure, under the simplifyingassumption of symmetry, to simulated data as well as to foreign exchangereturn data, with favorable results. Kanter projection coefficients governingconditional expectations are computed from the estimated spectral density. For the simulated data these compare well to their known true values.     

On the model-based networked control for singularly perturbed systems

In this paper, the control of a two-time-scale plant, where the sensor is connected to a linear controller/ actuator via a network is addressed. The slow and fast systems of singularly perturbed systems are used to produce an estimate of the plant state behavior between transmission times, by which one can reduce the usage of the network. The approximate solutions of the whole systems are derived and it is shown that the whole systems via the network control are generally asymptotically stable as long as their slow and fast systems are both stable. These results are also extended to the case of network delay.     

设计不安于“弃”——永续性环保设计

工业设计主要研究的是人、产品、环境三者之间的关系。所以好的工业设计产品要同时满足环境和人的心理的需要。本文以此为出发点,基于现在环境的恶化和人们之间的冷漠提出"永续性环保设计(Sustainable design)"的理念。通过介绍现今社会环境,提出此设计理念并提出了其设计方法。     

The Main Factors Affecting Isotopes of Yellow River Water in China

Abstract

Variation of δ¹⁸O, δD, and ³H in the Yellow River water were analyzed based on the isotope test results of water samples in 18 sections of the Yellow River in rainy and dry seasons. The results show the trend of the ratios of the stable isotopes increases while the ³H concentration decreases progressively from the river source to the estuary. The main factors affecting the isotopes in the river water are the mixing of foreign water bodies, evaporation, and human activities. River runoff mostly comes from the source and the middle reaches of the river. The changes of the isotopes in the river water could be served as a good indicator of the recharge of different foreign water to the Yellow River.     

周期环境下的最优的脉冲控制策略

研究了周期环境影响下具有脉冲控制的捕食与被捕食模型的全局动态行为,通过Floqnet理论和微分方程比较定理,得到了捕食系统害虫根除周期解的全局稳定性的临界值,进一步数值模拟分析了系统参数如何影响害虫综合控制,得到了最优的脉冲控制策略．     

冲积河流稳定平衡条件与断面几何形态的数理分析

冲积河流稳定平衡条件长期以来被认为无闭合解,致使众多经验假说得以应用。本文通过将两个无量纲断面形态参数宽深比和边坡角度引入到冲积河流三大基本运动方程中,详细分析了推移质输沙率与这两个变量之间的复杂关系,从数学上推导得出冲积河流达到稳定平衡的水动力学条件是推移质输沙率最大。河流达到稳定平衡时的过水断面形态数学表达式表明,天然冲积河流在平滩水位时所展现的水力几何关系是河流通过调整过水断面形态达到的稳定平衡的结果。     

静宁县建立农村供水工程投入稳定增长机制的思考

依据2011年中央1号文件关于建立水利工程投入稳定增长机制的政策措施,结合静宁县农村供水工程投资实际,探究建立公共财政投资和金融投资建设供水主体工程,群众投资投劳建设供水入户工程,社会资金投入提高供水入户标准的农村供水工程投入稳定增长机制,为工程实施提供资金保障.