基于DSP的闭环光纤陀螺研究

提出了一种基于DSP的全数字闭环光纤陀螺设计方案。文中对该闭环光纤陀螺的A／D、D／A等部分间的时序逻辑进行了设计和实现。讨论一种通过反馈调整D／A的基准电压来实现对2π复位不准确的控制。给出几个重要参数的测定方法和实验结果。     

锥形阀压电薄膜泵的初步研究

提出一种适应高频工作状态的压电薄膜泵结构，实步分析了所采用的锥形阀的工作原理与作用，设计了试验泵结构，加工了样机，通过试验证明了锥形阀的有效性，为进一步的研究打下了基础。     

乙烯裂解炉辐射段流动与燃烧的三维数值模拟

用计算流体力学软件Fluent6.2对中国石油化工股份有限公司燕山分公司E-BA-107乙烯裂解炉辐射段内的流动和燃烧做了三维数值模拟研究。为保证计算的准确性,使用GAMBIT2.2软件建立了与裂解炉实际尺寸完全一致的几何模型;在计算过程中采用了标准k-ε湍流模型、离散坐标辐射模型和有限速率/涡流耗散燃烧反应模型等计算模型。通过模拟计算得到了裂解炉炉膛内的温度、烟气流速及烟气组成的分布:底部燃烧器和侧壁燃烧器的燃烧使附近的炉墙处于温度分布均匀的高温区,为裂解反应提供了均匀的辐射墙面;炉管底部比其他部位的温度低;底部燃烧器的高速射流产生的旋涡可为炉管提供一定的对流热;出口烟气的平均温度和组成的模拟计算值与设计值接近,表明数值模拟有较高的精度,具有实际意义。     

On the unequal error protection for progressive image transmission.

In this paper, we consider the unequal error protection (UEP) for progressive image transmission when the coded packet size is fixed. First, we prove that, for the source code with convex rate-distortion (R-D) function and practically used channel codes, the channel code rate for each packet in the optimal rate allocation is nondecreasing indeed. Then, we give an upper bound for the channel code rate of the last packet so that the number of rate allocations in the exhaustive search can be predicted. Further, we propose a heuristic optimization method which has low complexity and obtains performance approaching to the optimal solutions for various channel conditions and transmission rates.     

木寡糖的研究进展

木寡糖可以从多种多样含木聚糖的原材料中通过化学法或酶法制得，然后再利用物理化学方法精制。作为食物配料，木寡糖具有许多有利的技术特性，并且具有调节肠功能的能力，能导致生物前效应。除了对肠功能的作用外，其他关于木寡糖的生物活性也作了相关综述，包括木寡糖在生物合成配置方面的作用以及他们的技术特性和市场前景。     

激光器实用价值的评判

提出用于评价激光器产品实用价值的Q因子,它由激光器的亮度、脉冲宽度及价格确定。Q值大的激光器,开发及发展的潜力大。     

基于语法的元程序设计系统的自动生成技术

本文提出一种基于语法的元程序设计系统的自动生成技术，并开发了一个元程序设计系统的自动生成系统Ａ－ＭＰＳ。元程序设计系统是一种以程序作为操作对象的有效的程序设计工具，并具有广泛的应用。     

NADPH diaphorase activity in mammalian retinas is modulated by the state of visual adaptation

NADPH diaphorase histochemistry is commonly used to identify cells containing nitric oxide synthase (NOS), the enzyme catalyzing the production of nitric oxide from L-arginine. NADPH diaphorase activity and NOS immunostaining was demonstrated in different cells of the vertebrate retina; photoreceptors, horizontal cells, amacrine cells, ganglion cells, and Müller cells. However, the physiological role of nitric oxide (NO) in the retina has yet to be elucidated. In this study, we tested the assumption that NADPH diaphorase activity in the retinas of rabbits and rats depended on the state of visual adaptation. In the rabbit, light adaptation enhanced NADPH diaphorase activity in amacrine cells and practically eliminated it in horizontal cells. Dark adaptation induced the opposite effects; the NADPH diaphorase activity was reduced in amacrine cells and enhanced in horizontal cells. Retinas from eyes that were injected intravitreally with L-glutamate exhibited a pattern of NADPH diaphorase activity that was similar to that seen in dark-adapted retinas. In rats, the NADPH diaphorase activity of amacrine and horizontal cells exhibited adaptation dependency similar to that of the rabbit retina. But, the most pronounced effect of dark adaptation in the rat's retina was an enhancement of NADPH diaphorase activity in Müller cells, especially of the endfoot region. Assuming that NADPH diaphorase activity is a marker for NOS, these findings suggest that NO production in the mammalian retina is modulated by the level of ambient illumination and support the notion that NO plays a physiological role in the retina.     

C_MPS的设计与实现

元程序设计系统是进行元程序设计的有效工具。C_MPS(CMetaProgra-mming System)是我们在PC机上开发的C语言的元程序设计系统,本文介绍了该系统的设计思想和实现技术。