A Dynamic Forecasting System with Applications in Production Logistics

Production logistics involve the co-ordination of ac tivities such as production and materials control (PMC), inventory management, p roduct life cycle management, etc. Those activities demand for an accurate forec asting model. However, the conventional methods of making sell and buy decision based on human forecast or conventional moving average and exponential smoothing methods is no longer be sufficient to meet the future need. Furthermore, the un derlying statistics of the market information change ...     

织造过程中经纱张力计算机控制系统的研究

为了提高织机生产效率和扩大织造品种范围，提出了织造过程中经纱张力控制的目标和相适应的控制方案，研制了经纱张力计算机控制系统，达到了预期的性能指标。     

OPTIMAL SETTING-UP OF KNITTING ELEMENTS AND ITS EFFECT ON TENSION VARIATION

The dynamic yarn tension variations during knitting cycle are very difficult to control and be-come one of barriers to knitting on modern warp knitting machine.Examination of experimentaldata and theoretical analysis show that the relative position of spring rail to knitting elements suchas needle,guide as well as their displacement has noticeable effect on tension variation so that theknitting condition can be much improved by rearrangement of the knitting elements and theirmovement within a knitting cycle.     

Synthesis and characterization of novel thermoresponsive‐co‐biodegradable hydrogels composed of N‐isopropylacrylamide,poly(L‐lactic acid), and dextran

A series of novel multifunctional hydrogels that combined the merits of both thermoresponsive and biodegradable polymeric materials were designed, synthesized, and characterized. The hydrogels were copolymeric networks composed of N‐isopropylacrylamide (NIPAAM) as a thermoresponsive component, poly(L‐lactic acid) (PLLA) as a hydrolytically degradable and hydrophobic component, and dextran as an enzymatically degradable and hydrophilic component. The chemical structures of the hydrogels were characterized by an attenuated total reflection–Fourier transform infrared spectroscopy (ATR–FTIR) technique. The hydrogels were thermoresponsive, showing a lower critical solution temperature (LCST) at approximately 32 °C, and their swelling properties strongly depended on temperature changes, the balance of the hydrophilic/hydrophobic components, and the degradation of the PLLA component. The degradation of the hydrogels caused by hydrolytic cleavage of ester bonds in the PLLA component was faster at 25 °C below the LCST than at 37 °C above the LCST, determined by the ATR–FTIR technique. Due to their multifunctional properties, the designed hydrogels show great potential for biomedical applications, including drug delivery and tissue engineering. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5054–5066, 2004     

双馈电机运行速度对稳态性能的影响

研究双馈电机运行速度对双馈电机稳态性能的影响．首先对比了双馈电机运行于超同步转速及次同步转速时的稳态波形，然后对谐波及稳态参数的变化进行了分析．研究表明双馈电机稳态运行速度对其稳态运行性能有较大影响．     

基于长期计划的动态给水管网优化设计模型

鉴于给水管网的优化设计的重要作用，提出了更符合实际、准确度更高的基于长期计划的动态给水管网优化设计模型。其目标函数中，动力费采用与时间相关的函数计算，折旧大修费采用与管段损坏率相关的函数计算，并建立了相应的动态优化设计模型。可以更精确地得出基于长期计划考虑管网优化设计结果。     

系统的分散与集中的决策：（Ⅱ）分散控制效果分析

分散集中系统是一种重要的工业过程控制系统．合适的分散度有利于提高系统的性能指标，尤其是动态响应速度和误差时间的积分值都有明显地改善．文中提出若干系统分散的选择原则，并用仿真和理论分析加以证明．     

关于高维系统中Poincαre—Bendixson定理的反例

本文给出了在n(n≥4)维系统中,Poincare-Bendixson定理不成立的多项式系统的反例。     

自级联式感应电动机控制系统的研制

描述了自级联式感应电动机的数学模型及其控制系统的结构,研制成功该类电机矢量控制系统样机.根据实验结果,分析了其动态和静态品质,得出此种类型电机控制系统完全可以达到与直流电动机控制系统相同性能的结论,提出了自级联式感应电动机进一步的应用前景.