NiCuZn铁氧体和银内电极的共烧行为

NiCuZn铁氧体正作为磁介质广泛地应用于低烧多层片式电感，因此有必要对其与银内电极的共烧行为进行研究。该文主要介绍NiCuZn铁氧体／银内电极多层复合体共烧过程中的烧结收缩、界面反应、扩散对介质性能的影响。尖晶石结构中存在相当数量的空位，这为银离子提供了一定的溶解度，因此在共烧过程中银对铁氧体的相组成影响较小。银对铁氧体性能的影响体现在两个方面。一方面是由于银具有相对低的烧结温度，从而在烧结过程中起到助烧剂的作用，促进致密化过程，提高烧结体的密度和磁导率；另一方面，银促使铁氧体中的铜在晶界处析出，导致晶界处应力，使磁导率降低，晶粒生长也被一定程度地抑制。     

DDS技术在数字激光相位测距仪中的应用

本文介绍了直接数字合成(DDS)技术在激光相位测距仪中的应用。使用该技术研制的数字激光相位测距仪具有操作简便、携带方便、性能可靠的特点，测相精度优于干分之一。     

ANALYSIS AND PROCESSING OF LMF－COSTAS STEPPED FREQUENCY RADAR SIGNAL

Linear Modulated Frequency (LMF) Costas Stepped Frequency Radar (SFR) signal is introduced. Its ambiguity function is derived and analyzed in detail and its feasibility is validated in theory. The scheme of the proposed signal processing is also presented. The results of theoretic analysis and simulation show that, by using the proposed signal and increasing the bandwidth of the total stepped frequency, the ambiguity sidelobe is well suppressed and the range-velocity coupling in the stepped frequency radar is also greatly weakened.     

PPT光纤波片耦合模方程的解析解

理论分析了PPT光纤波片耦合模方程，得出了一定条件下的解析解，将该解析解和渐进近似结果进行了比较，它们在实际应用的PPT光纤波片中具有很好的一致性。     

预测气吹精密播种机排种质量的一种简易方法

通过对气吹式精密播种机田间试验资料的相关分析，发现合格指数Ａ与｜Ｄ－Ｍ｜（重播指数与漏播指数之差的绝对值）之间里极显著负相关（ｒ＝－０．９３１２）。在对数据作进一步回归分析的基础上，本文建立了一套“由排种粒数预测排种质量”的方法。     

Electromagnetic micromirror array with single-crystal silicon mirror plate and aluminum spring

We have designed and fabricated an addressable 4 /spl times/ 4 array of micromirrors capable of providing up to 90/spl deg/ of angular deflection. Each micromirror comprises a single-crystalline silicon mirror plate supported by aluminum springs, which provides an extremely flat reflective surface and a compliant spring material that enables the integration of the device into a limited area without mitigating its performance (i.e., total angular deflection). The device is fabricated using a combination of surface and bulk micromachining processes, such as electroplating, bulk wet etching and XeF/sub 2/ etch processes. Selective actuation is accomplished by the use of an electrostatic clamping force on each mirror plate. A mirror rotation angle of more than 80/spl deg/ can be obtained by applying an external magnetic field, and this angle can be further increased by the use of an electrostatic force. The designed structure can be used in microphotonic applications.     

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。     

Effect of carbon content on the microstructure and the cracking susceptibility of Fe-based laser-clad layer

The laser cladding of Fe-based alloys on a medium carbon steel substrate was performed using a CO₂ laser and Ar shielding gas that was blown into a molten pool. The microstructure and cracking susceptibility of the laser-clad layers were studied in terms of carbon additions. Results show that the small change of the carbon content in the alloy powders can obviously change the microstructure and properties of the layers. When the carbon content is in the range of 0.3–0.4 wt.%, the decrease of the carbon content in alloy powders will increase the hardness and toughness of the layers simultaneously under the same process parameters. As a result, crack-free coatings with high hardness can be obtained. As the carbon content increases from 0.2 wt.% to 0.4 wt.%, the segregation ratio of chromium increases, while the segregation ratios of nickel, manganese, and silicon first decrease and then increase. At the same time, a new designing principle concerning the composition and microstructure has been put forward, and the principal mechanisms of strengthening and toughening of the layers are fine-grain strengthening and low carbon martensitic phase transformation strengthening.     

分布式协作工作流技术研究

工作流是实现企业业务过程建模、优化、管理、集成和自动化的核心技术．作为分布式的应用平台，工作流管理系统任务处理能力即吞吐能力是一个重要的性能指标．目前，已有的工作流管理系统在这方面存在较大的不足，成为工作流管理系统广泛应用的严重障碍．本文研究了工作流系统的协作方式和负载平衡技术，定义了工作流系统的负载因子，给出了一个分布式协作工作流系统模型，并结合业务流程逻辑，提出了分布式协作工作流系统负载平衡调度算法．实验表明该分布式协作工作流系统有效地扩展了单个工作流系统的吞吐能力。