HP83480数字通信分析仪的硬件测量算法

参数测量主要指对波形特性，如上升时间、下降时间、过冲、周期、脉冲波形或眼图的幅度等。掩码测量将波形与预定掩码比较。眼参数测量是专用于眼图性质的测量，如眼高、眼宽、抖动、交叉高度和消光比等。     

新型URE-2000S型紫外单、双面深度光刻机研制

重点介绍新近开发的用于单、双面深度曝光的URE-2000S新型紫外光刻设备的技术背景、工作原理、结构组成、技术措施以及总体性能。该设备采用了国内首创的CCD图像底面对准技术、单曝光头实现双面对准曝光,具有双面套刻对准精度高、操作简单、工作高效等优点。实验表明,该设备总体性能处于国产双面光刻的先进水平,接近国外同类产品水平。     

Novel deprocessing technique for failure analysis of flip-chip integrated circuit packages

A novel technique for flip-chip package deprocessing that allows for detailed failure analysis of internal flip-chip packaging structures and chip circuitry has been developed. A systematic approach of selective wet etching and plasma etching is utilized. Understanding of package level reliability can be greatly enhanced with the capability to systematically access and examine defects in three-dimensions with powerful analytical tools such as the SEM/EDS. Additionally, the ability to inspect large areas of internal packaging structures, e.g., solder bump array, in three-dimensions makes it faster and more convenient to locate defects, compared to two-dimensional techniques such as progressive cross-sectioning. Case studies involving defects in solder bumps, underfill material, and substrate metallization are presented.     

Effects of texture on the etching property of Fe-36%Ni invar sheets

In order to make a high quality color cathode ray tube, the influence of the texture on the etching property of an invar (Fe-36%Ni) shadow mask sheet has been studied. For the etching property, new values (g_R-, a_R-value) are presented which are estimated with the intensity of the inverse pole figure for the normal direction of the sheet. Furthermore, for the decision of the etching property, RD-values which are calculated with ODF are suggested. A good etching property is obtained when the RD-value is more than 2. This article is based on a presentation made in the symposium “ ’ 99 International Symposium on Textures of Materials”, held at Sunchon National University, Sunchon, Korea, April 21 ~ 22, 1999 under the auspices of The Korean Institute of Metals and Materials and the Research and Development Center for Automobile Parts and Materials.     

An XPS study of tarnishing of a gold mask from a pre-Columbian culture

The tarnishing originated on a hammered gold mask was analysed. Red tarnishing was observed after three years of storage in an indoor environment in the Gold Museum of Banco de la República, Bogotá, Colombia. Silver sulphide (Ag₂S) and silver sulphate (Ag₂SO₄) compounds were identified as the origin of the tarnishing phenomenon, which is attributed to environmental contamination. Atomic absorption spectroscopy (AAS) and X-ray photoelectron spectroscopy (XPS) techniques were used.     

海底盾构修复冻结加固技术

在海底故障盾构修复施工中,在盾构切口前方采用双排冻结管和盾构两侧的辅助冻结管进行垂直局部冻结加固土体,使盾构前方形成罩形冻土帷幕,将切口端的漏水通道冻结封闭,为隧道清泥排水和盾构修复提供保障。考虑到海水含盐具有冻土帷幕厚度减小、冻土强度下降等对冻结的不利影响,对冻结方案进行了专门设计与冻结及施工过程的实测研究。通过对冻土温度监测数据的计算和分析,表明罩形冻土帷幕在海底盾构修复中取得了良好效果,验证了该冻结方案在海底盾构隧道修复中的可行性。     

一种释放负离子面膜的研制

论述了一种负离子面膜的研制过程。在面膜的制作过程中通过适当的途径加进负离子添加剂,从而使负离子在皮肤表面发挥还原性作用,使已经氧化的皮肤还原,恢复健康状态。通过多次实验,所得产品负离子释放量超过了700个/cm3,具有释放负离子稳定持久、发射远红外线、杀菌、消毒、保健等功效,达到了健康要求。     

一种基于防毒面具的通话系统

防毒面具的隔绝特性使得用户之间的通话较为困难,为解决其在烟雾、火灾、战场等复杂使用环境下的通信问题,基于点到多点和．董到点两项功能,构建一种基于防毒面具的无线通话系统。系统采用语音编码和跳频等技术方法,开发出防毒面具内置的小型多功能无线通话终端。经软硬件测试表明,系统通信安全可靠,保密性强,体积小,成本低。     

Learning to ignore the mask in texture segmentation tasks.

Although traditionally texture segmentation has been regarded as an automatic, preattentive process, participants confronted with texture segmentation in experimental settings (i.e., with brief presentation time and subsequent masking) are initially unable to perform the task. According to perceptual learning concepts, participants must learn to fine-tune their sensory channels before perception improves under restricted viewing conditions. The present article proposes an alternative perspective that emphasizes the role of the mask. Four experiments showed that the amount of observed learning depends on the structural and temporal homogeneity or heterogeneity of the mask. The authors suggest that learning consists of separating the task-relevant signal stemming from the texture from the task-irrelevant signal of the mask and of ignoring the mask. (PsycINFO Database Record (c) 2010 APA, all rights reserved)