Robust matrix 𝒟U‐stability analysis

In this paper, the problem of robust matrix root‐clustering is addressed. The studied matrices are subject to both polytopic and unstructured uncertainties. An original point is the large choice of clustering regions enabled by the proposed approach since these regions can be unions of possibly disjoint and non‐symmetric subregions of the complex plane. The precise purpose is, considering a specified polytope, to determine the greatest robustness bound on the unstructured uncertainty such that robust matrix root‐clustering is ensured. To reduce conservatism in the derivation of the bound, the reasoning relies on a framework based upon parameter‐dependent Lyapunov functions. The bound value is computed by solving an ?? ?? ? problem. Copyright © 2003 John Wiley & Sons, Ltd.     

电力通信状况月统计报表系统设计及开发

介绍了电力通信月报管理系统的设计和开发，该系统解决了传统通信月报的许多弊端和不便。利用计算机技术实现通信报表的自动收、发和处理，是电力通信运行管理自动化及其企业达标创一流的重要组成部分。该系统是自行开发成功的，并已进入试运行阶段。     

1/f类分形信号的小波去噪方法

提出了一种用基于分形信号在不同尺度下小波系数方差来估计噪声方差及分形信号参数的新方法,进而从加性白噪声背景下估计出1/f类分形信号。仿真实验结果表明:该方法简单可靠,有效可行,且事先不需要知道分形信号参数及加性白噪声的统计特性,并对信噪比估计误差有很好的鲁棒性。     

影响安徽省城乡居民住宅发展因素的分析

选用安徽省1981～2000年相关统计数据为样本，建立了城镇和农村居民人均住宅面积的多元回归方程，得出影响城乡居民住宅发展的原因，并据此对安徽省房地产市场的发展提出了建议。     

纳焦飞秒激光在有机材料表面刻划微结构光栅的研究

使用振荡器产生的飞秒激光在透明有机材料PMMA表面进行了刻划微结构光栅的研究．通过理论分析得到了飞秒激光参数和平台移动速度对线宽的影响，进行了系统的加工实验，加工结果与理论分析基本吻合．在透明有机材料PMMA表面进行了多种光栅的刻划，并对刻划的光栅进行了衍射和色散测试，调整光栅的尺寸和排列方式，得到了形状各异的衍射图案。     

HFPECVD法沉积BN薄膜及其生长机理的研究

本文介绍了用HFPECVD(hot filament plasma enhanced chemical vapor deposition)法制备BN薄膜.通过红外吸收谱和x射线衍射图谱分析确定,射频功率和反应气体(N2)气流量显著影响薄膜中立方相BN(c-BN)的相对含量.当射频功率小于200W时,薄膜中立方相的相对含量随它的增加而增大;而当射频功率大于200W时,则随它增加而减小.当N2气流量增加时,薄膜生长速率增加,但立方相的相对含量却减少.最后通过对不同沉积时间样品的红外吸收谱的分析对BN薄膜的生长机理进行了探讨.     

直动式溢流阀的分岔分析与实验

为了改善广泛应用的直动式溢流阀的颤振行为,考虑油液压缩性、管道弹性和阀芯碰撞阀座时的能量损失,建立了溢流阀无量纲形式的数学模型。以4种不同的弹簧预压缩量,作出了相位和向量场分布图,得到了系统的稳定平衡状态。应用非光滑动态系统理论和计算软件MATLAB,画出了单参数和双参数分岔图,发现系统存在Hopf分岔、极限环鞍结点分岔、广义Hopf分岔和尖点分岔等分岔现象。搭建了测试平台,得到了阀芯位移分岔图和频谱瀑布图,对数学模型进行了实验验证。结果表明,小流量时为混沌或周期碰撞震荡,增大流量可改善阀芯颤振行为,为周期非碰撞震荡或稳定平衡状态。此研究工作为直动式溢流阀的失稳机理和颤振行为提供了理论依据。     

Influence of inoculum and climatic factors on the severity of Fusarium head blight in German spring and winter barley

Fusarium head blight (FHB) of small cereals is a disease of global importance with regard to economic losses and mycotoxin contamination harmful to human and animal health. In Germany, FHB is predominantly associated with wheat and F. graminearum is recognised as the major causal agent of the disease, but little is known about FHB of barley. Monitoring of the natural occurrence of FHB on Bavarian barley revealed differences for individual Fusarium spp. in incidence and severity of grain infection between years and between spring and winter barley. Parallel measurement of fungal DNA content in grain and mycotoxin content suggested the importance of F. graminearum in winter barley and of F. langsethiae in spring barley for FHB. The infection success of these two species was associated with certain weather conditions and barley flowering time. Inoculation experiments in the field revealed different effects of five Fusarium spp. on symptom formation, grain yield and mycotoxin production. A significant association between fungal infection of grain and mycotoxin content was observed following natural or artificial infection with the type B trichothecene producer F. culmorum, but not with the type A trichothecene-producing species F. langsethiae and F. sporotrichioides. Trichothecene type A toxin contamination also occurred in the absence of significant damage to grain and did not necessarily promote fungal colonisation.     

Impact of cycling temperatures on Fusarium verticillioides and Fusarium graminearum growth and mycotoxins production in soybean

BACKGROUND: Fusarium graminearum and F. verticillioides are two very important mycotoxigenic species as they cause diverse diseases in crops. The effects of constant and cycling temperatures on growth and mycotoxin production of these species were studied on soybean based medium and on irradiated soya beans. RESULTS: F. graminearum grew better when was incubated at 15, 20 and 15–20 °C (isothermal or cycling temperature) during 21 days of incubation. Maximum levels of zearalenone and deoxynivalenol (39.25 and 1040.4 µg g^?1, respectively) were detected on soya beans after 15 days of incubation and the optimal temperature for mycotoxin production was 15 °C for zearalenone and 20 °C for deoxynivalenol. F. verticillioides grew better at 25 °C in culture medium and at 15/20 °C and 15/25 °C on soybean seeds. Fumonisin B₁ was produced only in culture medium, and the maximum level (7.38 µg g^?1) was found at 15 °C after 7 days of incubation. CONCLUSION: When growth and mycotoxin production under cycling temperatures were predicted from the results under constant conditions, observed values were different from calculated for both species and substrate medium. Therefore, care should be taken if data at constant temperature conditions are to be extrapolated to real field conditions. Copyright © 2012 Society of Chemical Industry