Uniform theory of the Talbot effect with partially coherent light illumination

A uniform formulation for the self-imaging of gratings with any kind of partially coherent illumination is developed in terms of the cross mutual spectral density of the partial coherence theory. The formulation includes the time diffractive intensity distribution and the averaged diffractive intensity distribution at self-imaging distances and can be applied to both continuous and temporal illuminations with any kind of spectra. It is found that the averaged intensity distribution is related only to the intensity spectrum of illumination. The continuous polychromatic illumination and the ultrashort laser pulses with or without frequency chirp are then studied by a numerical stimulation. It is shown that the ultrashort laser pulse and the continuous polychromatic illuminations have similar averaged self-image distributions. Thus the Talbot effect may help in the study of the temporal and spectral characteristics of ultrashort laser pulses. An experiment with an LED is given, as well.     

21世纪北方城市新型住宅体系的探讨

从社会经济发展角度论述了建立北方城市新型住宅体系的必要性 ,提出发展新型住宅体系 ,以适应住宅产业化要求的思路。根据社会经济可持续发展要求 ,阐明对 2 1世纪北方型城市住宅体系的基本要求 ,提出实现新体系的生产方式和推进新型体系形成的途径     

The effect of IP traffic on WDM-based networks

In this letter me show that when IP traffic is loaded directly over WDM-based networks, the burstiness of the IP packets can have significant effects on the network performance through its influence on the fiber nonlinear effects, mainly the four-wave mixing effect provided the fiber input light power is high, the frequency spacing is narrow and IP traffic load is heavy     

热释电激光能量计

本文通过求解热传导方程分析了几种脉冲辐射作用下热释电信号的解析表达式。用简化模型和数值计算两种方法着重讨论了在近似激光脉冲辐射作用下，信号电压的规律性。得到了峰值电压正比于激光能量的条件和结论。介绍了PLEM-1型激光能量计的原理结构、电路和性能，并对仪器误差进行了初步分析。     

Selection of representatives for feedback suppression in reliablemulticast protocols

The representative scheme in which a small set of multicast group members are selected as representatives to represent congested areas and hence suppress feedback from other receivers is an effective way of avoiding feedback implosion. Two algorithms used for selecting group members as representatives are further investigated. It is shown through simulation that the algorithm that selects representatives using the loss probability observed at the receivers is more effective in reducing the feedback returned     

用能量色散X荧光法测定磁盘磁层厚度

用放射源~(238)Pu激发磁盘磁层中铁的特征X荧光来测定磁层厚度,具有快速、非破坏、精度高等优点。本文叙述测量原理、探测装置考虑、干扰因素的排除及数据处理。测定厚度范围为0.5—15μm。当厚度大于1μm时,测量精度好于5％。     

仿真模型有效性定量确认方法

仿真模型有效性评估是当今国际仿真界研究的一个热点问题。它主要包括模型确认和模型验证两部分内容。本文综述了仿真模型确认方法，重点介绍了在工程上适用的仿真模型有效性评估的定量化确认的统计检验方法。最后用实例说明方法的使用情况。     

细菌视紫红质膜的实时读写特性研究

对细菌视紫红质（ＢＲ）膜作为实时全息介质的读写特性作了理论和实验研究，分析了两种读出模式：连续读出模式和脉冲读出模式。结果表明连续读出模式的强度很小，而脉冲读出模式可以实现高强度的读出。对脉冲读出的技术要求作了理论上的探讨     

An IC yield enhancement approach by ARMA modeling and dynamic process control

The IC industry has been growing rapidly in the past decades. The continuous scaling-down of the feature size requires IC machines of highest performances, and pushes the IC manufacture to its utmost technology limits. Nowadays, IC manufacturers employ tightly fixed process parameters as their strategy to improve the yield. In this paper, a “softer” way is proved to be more potential in further improving and managing the yield of IC products. A novel concept which suggests running an IC procedure with dynamic process parameters is explained in detail. By using auto-regressive moving-average (ARMA) model, effects of the key process steps can be predicted and the related process parameters can be adjusted self-reactively. Since the discussion indicates distinct improvements of the IC yields, it seems the time to break the rule of “using stationary process parameters”.     

高压射流磨振荡反应腔CFD模拟及结构优化

目的：解决工业级高压射流磨（industry-scale microfluidizer，ISM）在实际应用中存在的进料要求高、处理量小、处理效果不佳问题。方法：结合CFD-PBM模拟和乳液制备试验对4种振荡反应腔进行选优，再通过尺寸优化获得最终腔型。结果：4种反应腔相比于原反应腔都拥有更大的孔径和流量；粒径细化效果为T字撞击型＞T字—二次撞击型＞十字撞击型＞二分管型4种反应腔的分流管区均主要存在剪切作用力，撞击管区主要存在撞击作用力，射流管区主要存在剪切作用力和空穴作用力，以上3个区域均存在强湍流。对T字撞击型反应腔进行尺寸优化，得到最终的反应腔模型，其最小管径为0.7 mm，在120 MPa下流量可达878 L/h。优化所得腔型制备的乳液粒径为249 nm，与模拟粒径结果吻合良好。结论：T字撞击型反应腔更具粒径细化优势，撞击作用力是粒径细化的主要因素。