预测控制算法的统一格式及其在电加热炉的应用

本文根据常用的两类预测控制算法推出一种新型预测控制算法。并将其应用于一双输入/双输出的力学持久机电加热炉的温度控制系统上,获得了满意的结果:控温精度为±1.5℃/300℃,且适用于非最小相位系统。     

K- and Q-bands CMOS frequency sources with X-band quadrature VCO

Fully integrated 10-, 20-, and 40-GHz frequency sources are presented, which are implemented with a 0.18-/spl mu/m CMOS process. A 10-GHz quadrature voltage-controlled oscillator (QVCO) is designed to have output with a low dc level, which can be effectively followed by a frequency multiplier. The proposed multipliers generate signals of 20 and 40 GHz using the harmonics of the QVCO. To have more harmonic power, a frequency doubler with pinchoff clipping is used without any buffers or dc-level shifters. The QVCO has a low phase noise of -118.67 dBc/Hz at a 1-MHz offset frequency with a 1.8-V power supply. The transistor size effect on phase noise is investigated. The frequency doubler has a low phase noise of -111.67 dBc/Hz at a 1-MHz offset frequency is measured, which is 7 dB higher than a phase noise of the QVCO. The doubler can be tuned between 19.8-22 GHz and the output is -6.83 dBm. A fourth-order frequency multiplier, which is used to obtain 40-GHz outputs, shows a phase noise of -102.0 dBc/Hz at 1-MHz offset frequency with the output power of -18.0 dBm. A large tuning range of 39.3-43.67 GHz (10%) is observed.     

冲击回波法检测隧洞混凝土衬砌厚度

冲击回波法是通过接收、分析在混凝土中传播的回波信号，判断结构混凝土厚度和内部质量的新型无损检测技术。室内试验和工程应用研究表明，该方法为隧洞混凝土衬砌厚度检测提供了一个有效的测试手段。     

共面转换液晶显示器中获得对比度高于1:600的新技术

薄膜晶体管液晶电视(TFT-LCD TV)因为具有薄、轻、紧凑和可随意放置的特点，已经占据了大部分电视机市场。除了这些物理特性以外，最重要的特性是已具有了良好像质的对比度。为了将对比度提高到1：600以上，对偏振片膜、背光源板、滤色片树脂、电极锥角和摩擦条件等都进行了研究。优化的背光板组合，光滑的电极锥角和摩擦方法的控制是提高对比度的主要控制因素。应用新开发的滤色片树脂，对获得高对比度最为有效。     

基于FPGA的图像几何矩计算实时实现

在Hatamian数字滤波器算法和改进的数字滤波器算法基础上,文中设计了累加器和累加器栅格的结构,消除了几何矩计算中乘法运算,进一步简化了加法运算量,实现了基于FPGA的几何矩计算实时实现.累加器表的仿真实验表明,该累加器表能够完成图像(256×256)几何矩的实时计算,同时该累加器表也可以用于图像质心的计算.     

Thermo-acoustic instability in the horizontal Rijke tube

The instability curve of a Rijke tube system was obtained accurately by following different paths of heat power and flow-rate for three regions and by defining its locus from the criterion based on the measured sound pressure levels. The unstable limits in the region of flow-rate lower than that at the minimal power are compared with previous data. To observe the effect of turbulence on the unstable limits, inflow turbulence was introduced by placing a bundle of circular cylinders upstream of the heating part (50< Re_d< 700). The large-amplitude inflow fluctuation may delay the transition of the chamber acoustic mode to the unstable zone even at a sufficient power.     

油酸臭氧化制备壬二酸

对以臭氧为氧化剂 ,由油酸制备壬二酸的工艺进行了研究 ,并讨论了各主要因素如溶剂与油酸的体积比、臭氧化温度、催化剂的种类和用量以及氧化分解时间对反应的影响。结果表明 :当臭氧化温度为 2 5～ 30℃ ,催化剂用量质量约为油酸的 0 .0 8%～ 0 .12 % ,氧化分解温度为 90～ 95℃ ,反应时间为 2 .5h ,壬二酸的收率为 4 7.1%。     

MS方法的一个新证明及其结构优化算法

本文给出Ｍｉｌｎｅ－Ｓｉｍｐｓｏｎ（ＭＳ）预测─校正法新的导出方法，并以结构优化思想设计出通用性和可靠性较强的算法。     

Improved domino logic for high speed design

Techniques are introduced to improve the speed of domino logic. With an inverted clock scheme, a serial transistor is removed and capacitances at the output node are reduced in the new structures. HSPICE simulation shows that over 20% performance enhancement is achieved.     

Effect of the absence of lipoxygenase isoenzymes on the storage characteristics of rice grains

Three varieties of paddy rice with and three varieties without lipoxygenase (LOX) isoenzymes were stored at room temperature, in dark conditions for 42 months. Insect damage and viability were investigated during that time. Varieties without LOX-1,2 and their offspring were screened with a rapid method of estimating LOX isoenzymes, and subjected to an accelerated-ageing experiment. The results indicated that in varieties without LOX-1,2, after long storage, rice quality was normal, but for varieties with LOX-1,2, rice quality deteriorated. With increase of storage time, the germination rate of the seed of most varieties decreased greatly except for varieties without LOX-1,2 where there was almost no change in the germination rate. In varieties without LOX-1,2 and their offspring, after an accelerated ageing experiment the germination rate of some varieties changed slowly, but with others, the germination rate changed quickly. This indicated that a definitive factor, which influenced the life of seeds, may be the loss of LOX-1,2. During storage, there was also a significant difference in the degree of insect damage. In varieties without LOX-3 insect damage was lower, but in varieties with LOX-3 insect damage was higher. Therefore, the absence of LOX-3 may be very important in insect resistance in rice grain.