模拟流体力学的离散运动论模型

模拟流体力学的离散运动论模型李元香（武汉大学软件工程实验室）ＤＩＳＣＲＥＴＥＫＩＮＥＴＩＣＭＯＤＥＬＳＦＯＲＳＩＭＵＬＡＴＩＮＧＦＬＵＩＤＤＹＮＡＭＩＣＳ￥ＬｉＹｕａｎｘｉａｎｇ（ＬａｂｏｒａｔｏｒｙｏｆＳｏｆｔｗａｒｅＥｎｇｉｎｅｅｒｉｎｇＷｕｈａ...     

固态盘的可靠性设计

给出固态盘（ＳＳＤ）的ＥＤＡＣ时序、存储体出错信息ＦＩＦＯ队列管理、掉电保护、设备自检、ＳＥＴ、ＲＥＳＥＴ键功能等可靠性措施的设计。实际证明，这些措施有效地提高了该系统设备的可靠性。     

冤家路窄

众所周知ＭＩＣＲＯＳＯＦＴ（微软）、ＮＥＴＳＣＡＰＥ（网景）是一对冤家对头,连他们的软件也不例外。 网民Ｂ在装有ＮＡＶＩＧＡＴＯＲ的机器上安上ＩＥ以后,只见两个软件的图标在屏幕上扭打成一团,接着ＶＢ,ＶＩ－ＳＵＡＬ　ＦＯＸＰＲＯ也加入了对ＮＡＶＩＧＡＴＯＲ的拳打脚踢。 Ｂ只得关机。重新启动后,只见ＩＥ重新安排了桌面,ＮＡＶＩ－ＧＡＴＯＲ已被赶到了回收站里。冤家路窄     

空间表面三角形二次单元网格自动剖分

空间表面三角形二次单元网格自动剖分张德贤，刘筱连，师汉民，陈日曜（华中理工大学机械工程一系）ＡＵＴＯＭＡＴＩＣＧＥＮＥＲＡＴＩＯＮＯＦＴＲＩＡＮＧＵＬＡＲＳＩＸ－ＮＯＤＥＥＬＥＭＥＮＴＳＯＦＴＨＲＥＥ－ＤＩＭＥＮＳＩＯＮＡＬＳＵＲＦＡＣＥＳ￥Ｚｈａｎ...     

加强并行处理关键技术与并行算法研究（代序）

加强并行处理关键技术与并行算法研究（代序）ＩＮＴＲＯＤＵＣＴＩＯＮ：ＭＯＲＥＥＦＦＯＲＴＳＮＥＥＤＥＤＴＯＳＴＵＤＹＫＥＹＰＡＲＡＬＬＥＬＰＲＯＣＥＳＳＩＮＧＴＥＣＨＮＯＬＯＧＩＥＳＡＮＤＰＡＲＡＬＬＥＬＡＬＧＯＲＩＴＨＭＳ中国科学技术大学计算机系郑...     

流水线结构RS(255,223)译码器的VLSI设计

ＲＳ码已经广泛应用于通信系统,计算机系统,存储介质,网络和数字电视中,以提高数据的可靠性;ＲＳ（２５５,２２３）码是美国航空航天局（ＮＡＳＡ）和欧洲空间站（ＥＳＡ０在深空卫星通信系统中所采用的标准外码。文中用Ｔｏｐ－ｄｏｗｎ设计方法完成了采用频域译码算法的ＲＳ（２５５,２２３）译码器的ＶＬＳＩ设计,提出了一个ＧＦ（２５６）上串行计算的流水线结构的２５５点ＩＦＦＴ,该结构的ＩＦＦＴ与译码器的其它模块     

三维有限元自动网格生成

三维有限元自动网格生成李玉成（中国科学院计算中心）向田康之（日本富士通ＢＳＣ）ＡＵＴＯＭＡＴＩＣＴＨＲＥＥ－ＤＩＭＥＮＳＩＯＮＡＬＦＩＮＩＴＥＥＬＥＭＥＮＴＭＥＳＨＧＥＮＥＲＡＴＩＯＮ￥ＬｉＹｕｃｈｅｎｇ（ＣｏｍｐｕｔｉｎｇＣｅｎｔｅｒ，Ａｃａｄｅｍ...     

Euler方程间断解的自动捕捉技术

Ｅｕｌｅｒ方程间断解的自动捕捉技术李松波，王运涛（中国空气动力学研究与发展中心）ＡＵＴＯＭＡＴＩＣＡＬＬＹＣＡＰＴＵＲＩＮＧＴＥＣＨＮＩＱＵＥＯＦＤＩＳＣＯＮＴＩＮＵＯＵＳＳＯＬＵＴＩＯＮＯＦＥＵＬＥＲＥＱＵＡＴＩＯＮＳ￥ＬｉＳｏｎｇ－ｂｏ；Ｗａｎｇ...     

一种新的求解线性时变系统的数值解法

一种新的求解线性时变系统的数值解法贾磊，孙优贤（山东轻工业学院机电系）（浙江大学工业控制研究所）ＡＮＥＷＮＵＭＥＲＩＣＡＬＭＥＴＨＯＤＯＦＴＨＥＬＩＮＥＡＲＴＩＭＥ－ＶＡＲＩＮＧＳＹＳＴＥＭＳＶＩＡＳＨＩＦＴＥＤＪＡＣＯＢＩＳＥＲＩＥＳ￥ＪｉａＬｅｉ...     

解二维扩散方程的分步分组显式格式

解二维扩散方程的分步分组显式格式陆金甫，曾光（清华大学应用数学系）ＦＲＡＣＴＩＯＮＡＬＳＴＥＰＳＧＲＯＵＰＥＸＰＬＩＣＩＴＭＥＴＨＯＤＳＦＯＲ２ＤＤＩＦＦＵＳＩＯＮＥＱＵＡＴＩＯＮＳ￥ＬｕＪｉｎ－ｆｕ；ＺｅｎｇＧｕａｎｇ（ＴｓｉｎｇｈｕａＵｎｉｖｅｒ...     

基于ISFET的农药检测生物传感技术

随着微电子、生物技术的发展,离子敏场效应晶体管(ISFET)生物传感技术已应用于农药检测,并显示出较好的优越性,而我国对基于ISFET的农药检测生物技术研究尚未展开。简单介绍了基于IS-FET的生物传感器的结构、原理,重点探讨了其在农药检测方面的研究应用,分析了ISFET生物传感器存在的问题与未来的发展。     

悬浮栅结构ISFET的HSPICE仿真

通过对ISFET敏感机理的分析,根据表面基模型,建立了悬浮栅结构ISFET器件的HSPICE行为模型,并对其静态输出特性,转移特性,以及pH值与界面势的关系进行了仿真,仿真结果表明:该模型与ISFET的理论和实验数据吻合较好。为ISFET/REFET差分结构集成传感器芯片设计提供了重要的理论参考价值。     

参比场效应晶体管(REFET)及 其与ISFET集成化的研究

本文介绍为实现带有参比电极的ISFET测量探头微型化而研制成的一种新型探头。采用等离子聚合方法在ISFET敏感栅上覆盖一层聚苯烯薄膜(PPS),使其成为对H~+不敏感的参比场效应晶体管(REFET)。而后采用IC艺,将ISFET,REFET和伪参比电极集成化,得到可用于微量溶液测量的微型探头,将探头中的ISFET和REFET按差分对管方式连接于差放线路中,由于两管对溶液中pH值响应不同,可输出随pH值变化的差模信号。研制的REFET在pH4～pH11范围内几乎无响应,表明了PPS膜具有较少的表面态及良好的H~+掩蔽性。用集成化探头测量pH值,灵敏度可达55mV/pH。     

CMOS兼容的ISFET传感器模型和测量电路研究

随着CMOS工艺的不断发展,将离子敏场效应晶体管(ISFET)传感器与CMOS技术相结合,以达到提高集成度、降低成本、减小系统尺寸、提高系统可靠性。在对与CMOS工艺兼容的ISFET传感器结构模型分析的基础上,研究了一种测量电路,它具有有利于消除体效应的影响、减少共模噪声的影响、克服温度漂移等优点。对该测量电路进行模拟仿真,得到输出电压与pH值之间的关系图,结果表明:其结果与理论模型仿真值基本吻合。     

CMOS离子敏场效应管SPICE模型

完全用CMOS工艺实现离子敏场效应型晶体管(ISFET)成为可能,这种ISFET的栅极结构是由绝缘体、多晶硅、金属层叠起来,称之为多层栅结构。从ISFET的传感机理出发,通过分析金属氧化物场效应晶体管(MOSFET)阈值电压的原理,利用通用电路模拟程序(SPICE)建立了这种多层栅结构ISFET的物理模型,并对其静态输入输出特性进行仿真,仿真结果和试验数据基本相符。     

ISFET source separation: Foundations and techniques

Ion-sensitive field-effect transistors (ISFET) are solid-state electronic devices for chemical sensing. They are sensitive to the concentration of a particular ion in the solution to be tested, but they can also be strongly affected by specific interfering ions found in the solution. They should therefore only be employed where possible interferences are negligible and this limits their range of operation. However, since ISFETs behave as non-linear mixers of main ion activities and interferences, blind source separation (BSS) techniques and related methods such as independent component analysis (ICA) are suitable for attempting to separate the original main ion activity and the interferences from the mixed response. In this paper, we review the most important groundwork and techniques that can be employed when using ISFET arrays in this way to sense particular ions. Several experiments based on linear independent component analysis (ICA) in a 2 NH₄-ISFET array demonstrate the usefulness of employing BSS for dealing with the separation of ion activities in ISFET responses and their later reconstruction in operating regions where interferences notably affect the response, and how this can cancel the interference effect in the ISFET response.     

A nozzle-type ultra-micro-volume multi-ion sensor using a rear-gate SIS/ISFET

A nozzle-type micro multi-ion (NMM) sensor suitable for ultra-micro-volume sample-solution analysis has been developed using a newly designed rear-gate silicon-insulator-silicon (SIS) three-layer structure ISFET chip. The sensor inner volume is only 2.5 μl from the nozzle tip to the ISFET part for sensing the temperature and three types of ions. The outer body of the sensor is also sufficiently small to be dipped into the standard miniature sample vessels used in automatic blood analysers. K⁺, Na⁺ and Cl^- ion-sensing membranes are formed on the ISFET, and their basic characteristics and durabilities are checked. Furthermore, the sample solution volume needed for the sensor is estimated from pH and K⁺ ion flow-through sensing measurements. As a result, the sensor durability to cleaning by a detergent solution has been more than doubled by means of the membrane-locking structure of the ISFET chip. Also, the sample volume needed for the measurement has been drastically reduced to about 20 μl including prior sample-solution rinsing.     

CMOS readout circuitry for ISFET microsystems

CIMP (complementary ISFET/MOSFET pair)—a novel technique for implementation of readout interface in CMOS ISFET-based microsystems is described. This design technique allows body effect elimination, temperature compensation and design simplicity, while maintaining constant biasing of ISFET sensor. Several configurations of CIMP interface provide applicability for array-type sensors. The general concept presentation is followed by a detailed analysis, test results showing 0.1% accuracy and layout implementations in a standard 1.6 μm CMOS technology.     

ISFET performance enhancement by using the improved circuit techniques

An approach to enhance accuracy of the output signal obtained from ISFET interface electronics due to the body effect is proposed. Based on an MOS drawing the same drain current as the ISFET, the scheme allows reduction of influence of body effect. The presented readout interface improves the accuracy of pH measurements, while maintaining operation at constant drain-source voltage and current condition. Using only one ISFET with a differential output configuration, we obtained temperature-dependency and long-term drift as well as common noise compensation. The proposed technique is simple and has a universal use for different ISFETs. In addition, a voltage-controlled dc offset error compensation circuit modulates the extracted signal to the desired dc level for the A/D converter for each sensor. Simulation and experimental results show a great effect on monolithic ISFET integration in CMOS technology.     

Temperature effect of a-Si:H pH-ISFET

In this article, the hydrogenated amorphous silicon (a-Si:H) acted as the sensitive membrane of pH-ISFET. The a-Si:H membrane was deposited by plasma-enhanced chemical vapor deposition (PECVD). In our experiment, we use a Keithley 236 Semiconductor Parameter Analyzer to measure the drain-source current (I_DS) vs. gate voltage (V_G) curve of a-Si:H ISFET over a pH range from 1 to 7 and a temperature range from 25°C to 65°C. According to our experimental results, we can observe that the pH sensitivity of a-Si:H ISFET is proportional to the operating temperature. And then, we can also find that the temperature coefficient of a-Si:H ISFET is proportional to the pH value of buffer solution.