GB50346生物安全实验室建筑技术规范修订要点

阐述了GB50346生物安全实验室建筑技术规范的修订原则,简要介绍了标准修订的主要内容。包括增加了生物安全实验室分类,高效空气过滤器原位消毒和检漏要求,存水弯和地漏的水封深度要求,污物处理设备性能验证等内容,完善了生物安全实验室选址要求,围护结构严密性检测要求,高等级生物安全实验室配电要求,消防要求,二级屏障技术指标要求。     

有线数字电视机顶盒技术要求和测量方法

本文详细解读了新颁布实施的有线数字电视机顶盒行业技术要求,重点介绍了有线数字电视机顶盒的基本技术要求及相应的测量方法.同时,将本次颁布实施的技术要求与原来执行的机顶盒技术要求进行了比较.     

电子设备模块化设计探讨

从机载电子设备的实际出发,对模块化设计进行初步探讨,对模块的可靠性要求、可维护性要求、互换性要求和电磁兼容性要求等通用性要求进行了论述。     

"等级化安全体系"是如何炼成的

在上一篇文章中,我们描述了联想网御安全理念的产生背景。国家从27号文到66号文,到电子政务等级保护实施指南,主要提出了等级化的要求,根据27号文的战略目标和综合防范原则提出了体系化的要求。从客户的要求角度也提出了体系化和等级化两方面的要求。等级化和体系化这是两个大方面的要求,基本上可以覆     

电视音乐类综艺节目音乐混音的要求与特点

本文结合工作实际,分析了音乐混音在整个后期制作中具体情况,并给出了详细的技术参数要求、听觉感受要求,以及制作周期和效率要求.     

贯彻电子技术基础课程教学基本要求

工科本科课程教学基本要求是工科本科学生学习该门课程必须达到的合格要求,贯彻基本要求的关键是:打好基础、培养能力,面对当前、放眼未来。几年来,我们在贯彻“基本要求”上进行了一些尝试。基本上达到了预期效果,本文将主要做法与体会作一简介。1 将“基本要求”融汇在整个教学过程 (1)在深入领会课程“基本要求”的基础上,根据学生情况,提出学习每章的“基本要求”,它源于“基本要求”,但一般高于“基本要求”,使之更加具体化、深入化,以便贯彻执行。     

半导体照明产品日本市场准入要求

文中介绍了半导体照明产品进入日本市场的安全要求、性能要求和EMC要求等,着重描述了日本标准与相关IEC标准的差异。     

方位瞄准中的高精度小角度的检测

利用激光干涉进行角度检测时对激光频率稳定性的要求很高,本文采用一种实用的方法降低了检测用激光器频率稳定性的高要求,降低了检测的成本,同时满足了检测的要求。     

天馈系列行业标准建设的作用及影响

天馈系列行业在世界上首次完整规范了对采用直接远场方法测试天线辐射参数的验收、场地及设备要求、鉴定级测试场地和设备要求,首次引入了多探头球面近场测量方法,规范近场场地及设备要求,首次规范了对天线环境与可靠性的测试场地和仪表要求.     

3G与固网视频互通解决方案

首先从技术角度阐述了3G与固网视频互通的解决方案,对互通系统进行了分析,然后讨论了对互通网关VIG的设备要求,包括VIG组网应用要求和VIG协议转换要求两个方面。     

A linear, time-varying system framework for noniterativediscrete-time band-limited signal extrapolation

A technique for the analysis and design of noniterative algorithms for discrete-time, band-limited signal extrapolation is described. The approach involves modeling the extrapolation process as a linear, time-varying (LTV) system, or filter. Together with a previously developed Fourier theory for LTV systems, this model provides a frequency-domain transfer function representation for the extrapolation system. This representation serves as a powerful tool for characterizing and comparing the reconstruction properties of several well-known least squares optimal algorithms for band-limited extrapolation. Moreover, the frequency-domain setting provides a conceptually attractive means for understanding the process of extrapolation itself. Additionally, a least squares approximation methodology for designing LTV filters for band-limited extrapolation is developed. The design technique is shown to unify a broad class of algorithms for extrapolating discrete-time data and, further, to provide a means for designing new and improved extrapolation algorithms     

Optimization of the Matching Network for a Hybrid Coupler Phase Shifter

A new theory is presented for how to find the optimum data for a transmission line used as a matching network for a hybrid coupler phase shifter. The theory gives a smaller phase-shift error and a greater bandwidth than already known methods. Two methods for equalization of the diode losses for a hybrid coupler phase shifter are described.     

Comparing between estimation approaches: admissible and dominating linear estimators

We treat the problem of evaluating the performance of linear estimators for estimating a deterministic parameter vector x in a linear regression model, with the mean-squared error (MSE) as the performance measure. Since the MSE depends on the unknown vector x, a direct comparison between estimators is a difficult problem. Here, we consider a framework for examining the MSE of different linear estimation approaches based on the concepts of admissible and dominating estimators. We develop a general procedure for determining whether or not a linear estimator is MSE admissible, and for constructing an estimator strictly dominating a given inadmissible method so that its MSE is smaller for all x. In particular, we show that both problems can be addressed in a unified manner for arbitrary constraint sets on x by considering a certain convex optimization problem. We then demonstrate the details of our method for the case in which x is constrained to an ellipsoidal set and for unrestricted choices of x. As a by-product of our results, we derive a closed-form solution for the minimax MSE estimator on an ellipsoid, which is valid for arbitrary model parameters, as long as the signal-to-noise-ratio exceeds a certain threshold.     

CMOS circuit optimization

In this paper, optimization algorithms for CMOS circuits are described, from the propagation delay time viewpoint. The propagation delay time for a CMOS in erter is calculated for a step function input. A classical model of I–V characteristics for a MOSFET and the worst case Sah model for inter-electrode capacitances of a MOSFET are used for this deduction.     

Modeling testing-strategies for yield enhancement of multichipmodule systems

This paper presents analytic models for evaluating test-strategy (TS) for yield enhancement of systems manufactured using fault-tolerant (FTol) multichip modules (MCM) for massively parallel computing. Several methods for testing FTol-MCM have been proposed, but there is little analytic evaluation. This paper uses a novel Markov model to compute the yield. Unlike a previous method which uses a binomial distribution, our TS can use intermediate tests (Intmed-T). This paper shows an efficient TS with a modest level of redundancy to achieve 100% first-pass MCM yield for a particular system. Two methods using Intmed-T for FTol-MCM are proposed and analyzed. When Intmed-T are used for all mounted chips, FTol-MCM with more than a few chips require known-good chips of at least a 99.9% probability-good for achieving a high yield. An efficient TS with a modest level of redundancy can exist for achieving a 100% first-pass MCM yield for a particular system. A yield-analysis model using the least recently tested (LRT) TS in this paper provides a very good figure-of-merit due to its cost, delivery, number of tests, and reliability benefits for current technology. Extensive parametric results for the analysis show that LRT-TS can be applied to calculate the overall yield for FTol-MCM more accurately and efficiently, thereby improving the system reliability     

A programmable integrated digital controller for switching converters with dual-band switching and complex pole-zero compensation

The design of a 0.6-/spl mu/m CMOS programmable integrated digital PID controller for a buck converter is presented. Several novel features are implemented. These include: 1) a dual-band switching scheme for sampling the output voltage for better output resolution; 2) a dual-band switching PWM generator with a modified tapped delay line for area efficiency; 3) a VCO driving a counter to serve as an ADC; 4) a programmable PID compensator employing variable integration times for enhancing accuracy and stability; and 5) complex pole-zero cancellation in extending the bandwidth of the control loop. The converter is designed for variable output applications, and the fast digital loop achieves a tracking time of 50 /spl mu/s for a 1-V step change of the reference voltage. The converter switches at 1 MHz and attains a maximum efficiency of 90% when delivering a load of 125 mW.     

Spatially Adaptive Estimation via Fitted Local Likelihood Techniques

This paper offers a new technique for spatially adaptive estimation. The local likelihood is exploited for nonparametric modeling of observations and estimated signals. The approach is based on the assumption of a local homogeneity of the signal: for every point there exists a neighborhood in which the signal can be well approximated by a constant. The fitted local likelihood statistics are used for selection of an adaptive size and shape of this neighborhood. The algorithm is developed for a quite general class of observations subject to the exponential distribution. The estimated signal can be uni- and multivariable. We demonstrate a good performance of the new algorithm for image denoising and compare the new method versus the intersection of confidence interval (ICI) technique that also exploits a selection of an adaptive neighborhood for estimation.     

Uniaxial chiral quarter-wave polarisation transformer

The uniaxial chiral medium is a generalisation of the well-studied isotropic chiral media. It is obtained when microscopic helices with parallel axes are positioned in a host dielectric in random locations. Solutions for the dispersion equation and for the eigenwaves for a uniaxial chiral medium were recently found. Here the authors consider the polarisation properties of a transverse wave propagating through a uniaxial chiral slab. The results give a simple possibility for constructing a polarisation transformer for changing the polarisation of a propagating plane wave.<>     

The Analysis of a Class of Non-Series Parallel Redundant Systems

Two analysis techniques for use in the study of a class of non-series parallel, dual channel systems are presented. The first technique is a method for obtaining an approximate solution for the system. It is based on a systematic analysis of first- and second-order failure modes and involves the use of matrix algebra. The second technique is a method for generating the exact solution from the approximate solution. This method involves a transformation which converts the system into a logically equivalent system. An exact solution for the transformed system is derived and is shown to be the exact solution for the original system.     

Transmission-Line Properties of a Strip on a Dielectric Sheet on a Plane

The subject is a strip Iine formed of a strip and a parallel ground plane separated by a dielectric sheet (commonly termed "microstrip"). Building on the author's earlier papers all the significant properties are formulated in explicit form for practical applications. This may mean synthesis and/or analysis. Each formula is a close approximation for all shape ratios, obtained by a gradual transition between theoretical forms for the extremes of narrow and wide strips. The effect of thickness is formulated to a second-order approximation. Then the result is subjected to numerical differentiation for simple evaluation of the magnetic-loss power factor from the skin depth. The transition formulas are tested against derived formulas for overlapping narrow and wide ranges of shape. Some of these formulas are restated from the earlier derivations and others are derived herein. The latter include the second-order approximation for a narrow thin strip, and a close approximation for a narrow or wide square cross section in comparison with a circular cross section. Graphs are given for practical purposes, showing the wave resistance and magnetic loss for a wide range of shape and dielectric. For numerical reading, the formulas are suited for programming on a digital pocket calculator.