Low noise accelerometer microsystem with highly configurable capacitive interface

This paper presents a low noise accelerometer microsystem with a highly configurable capacitive interface circuit. A programmable capacitive readout circuit is designed to minimize the offset and gain error due to the parasitic capacitance mismatch and the process variations. The interface circuit is implemented in a 0.5 μm 2P3M CMOS technology with EEPROM. The interface circuit and MEMS sensing element are integrated in a single package, and consist the accelerometer microsystem. The supply voltage and supply current of the system are 5 V and 1.17 mA, respectively. The input range and gain are 2.5 V and 0.5 V/g, respectively. The max–min gain error and max–min offset error after calibration was measured to be 1.2% FSO and 3.3% FSO, respectively. The signal to noise ratio (SNR) and noise equivalent resolution (NER) are measured to be 93.1 dB and 110.6 μg/√Hz, respectively, when a 40 Hz, 5 g sinusoidal input acceleration is applied.     

NGOSS中的收入管理

介绍了下一代运营支撑系统(NGOSS)在技术、功能、经济等几个方面的目标，指出帮助运营商提高收入、降低成本是NGOSS的最终目标。分析了影响运营商收入的相关因素，并提出了NGOSS的收入管理策略。     

Using policies for effective network management

The goal of policy‐based management is to reduce the complex administration of networks. Copyright © 1999 John Wiley & Sons, Ltd.     

构件化思想在教务管理系统中的应用

随着软件开发技术的不断发展,各种软件系统的设计方法不断涌现。为了构建高效可靠的教务系统,在设计时采用基于DCOM模型的多层体系结构和面向构件的方法,设计了一个基于构件化思想开发的系统。此教务系统集成平台为一个三层C/S结构的系统,实现中间件的功能。在此论述了该教务管理系统的设计思想、系统功能和系统架构。该系统的开发为软件开发人员和管理人员提供了一种新的思路和技术手段,并将软件复用的思想更好地应用到开发领域中。     

可配置的TFT-LCD控制器IP核的设计

设计实现了一种基于Avalon总线的,显示分辨率和像素深度均可配置的TFT-LCD控制器IP核.根据自顶向下的设计思想,将IP 核进行层次功能划分设计,采用Verilog 硬件描述语言实现该控制器以及它的外围逻辑时序的全部功能.并对IP 核进行仿真验证,最后加入到Nios II系统中,该IP 核经测试效果良好.     

RFID领域软件构件化开发技术研究

将软件构件化开发技术应用至RFID领域.基于领域工程的分析方法,对RFID领域内变化性需求进行封装、隔离和抽象,分析出RFID体系架构,提炼出RFID软件构件模型。针对构件的管理,研究了RFID构件的分类方法,提出刻面分类法,并详细描述RFID软件构件分类的刻面及每个刻面的术语空间。     

A configurable ROM circuit for use in gate arrays

A double word-line memory ROM (DWM-ROM) for use in gate arrays is described. It allows for an automatic layout by reducing the input pin count in the word lines by using two-step addressing. The advantage of this method has been verified by implementing a 16-bit microprocessor using an 8 K-gate array, based on a gate-isolated cell configuration, employing 1.5-/spl mu/m double-metal CMOS technology. The 16-bit /spl times/ 64-word ROM in the processor saves 30% of the transistor area due to the DWM-ROM.     

NandFlash中高位可配置BCH编码器的研究

为了满足存储器市场对于高存储容量的NandFlash的需求,在NandFlash控制器中ECC纠错模块的数据纠错与加密能力越来越受关注。文中实现了一种支持最大编码长度为8560,纠错能力可达24比特的BCH编码器。该编码器具备参数化配置的能力,可并行编码,并从面积与延时的角度对编码器做了数学优化。可以应用于固体硬盘主控、USB KEY等需要有NandFlash控制模块的芯片中。     

NGOSS在广电交互式网络电视系统中的应用探讨

文章分析了建立运维系统的必要性,并依据电信网络管理论坛新一代运营支撑系统研究计划的概念和应用原则,提出了建立广电交互式网络电视业务运维系统的一些设想。     

ASMBL——创新下一代平台FPGA

ASIC的非重发性设计(NRE）与设计时间高得惊人。在130纳米工艺水平下、ASIC的NRE为1千万美元或更多,设计ASIC芯片所需时间一般为13～18个月。此外,芯片技术规范中还包含有关应用适应性的内容。推动适应性需求的几项因素包括：     

Metropolitan DWDM: a dynamically configurable ring for the KomNetfield trial in Berlin

We present the system concept of a dynamically configurable all-optical add/drop multiplexer for metropolitan wavelength division multiplex rings using dense channel spacing (DWDM). We first outline the essential network requirements. Subsequently, an optical system concept is presented that meets these requirements. In the network elements, innovative all-optical switching technology is employed. Tunable fiber Bragg gratings that perform routing functions by wavelength filtering are discussed in more detail. The system is laboratory-tested. It has been installed in Berlin for a multi-vendor field trial within the German research program “KomNet.” Three optical add/drop multiplexers form a dynamically configurable Metro DWDM ring. Metro DWDM accommodates high bandwidths: a metropolitan ring that provides 0.8 terabit/s ring capacity has been demonstrated. Furthermore, Metro DWDM can provide optically transparent channels enabling the transport of various data formats simultaneously, e.g., SONET/SDH and Gigabit Ethernet. Conversion to a standard format becomes obsolete. The all-optical add/drop multiplexer (OADM) presented provides both manual and dynamic configuration. The system concept of the OADM is developed starting with basic metropolitan DWDM network requirements. The features of the DWDM ring are described, followed by a presentation of the system concept of the flexible OADM. Our focus is on dynamic configuration techniques. Since tunable fiber Bragg gratings are promising components for dynamic optical channel switching, this technology is treated in more detail     

Fault detection in configurable switched-capacitor filters using transient analysis and dynamic time warping

In this work, we address a low-cost test of switched capacitors filters embedded in configurable analog sections. The proposal improves the Transient Analysis Method (TRAM) by incorporating a similarity measure, dynamic time warping. In this way, we extend TRAM to cases that that initially were not compatible and simplify the test of filters of order higher than two. This paper performs the test evaluation by developing a new simulation model of the addressed system that supports fault injection and simulation. A comparison with experimental data in both normal and faulty behavior validates the model. We consider catastrophic faults in the switches (stuck at open and short) and capacitors (shorts and opens), and deviation faults in the capacitors. The fault simulation results validate the test proposed here.

     

Using Anfis with circular polygons for impulsive noise suppression from highly distorted images

In this paper, a novel approach is presented to the restoration of images corrupted by impulsive noise (IN), with a new nonlinear IN suppression filter, entitled circular polygons based adaptive-fuzzy filter (CF). The proposed filter is based on statistical impulse detection and nonlinear filtering which uses adaptive-network-based fuzzy inference system (Anfis) as a missed data interpolant over the circular polygons and provides estimates for the original intensity values of corrupted pixels. Impulse detection is realized by using the chi-square based goodness-of-fit test, which yields a decision about the impulsivity of each pixel. Extensive simulations were realized to demonstrate the capability of CF and they reveal that the proposed filter achieves a better performance than the other filters mentioned in this paper in the cases of being effective in noise suppression and detail preservation, also when the images are highly corrupted by IN.     

Layer-preference policies in multi-layer GMPLS networks

We address the problem of routing Label Switched Paths (LSPs) in multi-layer networks based on the Generalized MultiProtocol Label Switching (GMPLS) paradigm. In particular, we pursue policies for choosing the appropriate layer to host a new LSP request, as we find that such layer-preference policies have significant impact on network performance. We discuss several simple layer-preference policies and we reveal why these simple policies ruin network performance in the long run. Consequently, we develop an efficient heuristics, the Min-phys-hop routing and wavelength assignment algorithm, to govern the selection of the best layer of a multi-layer network in which to host new LSP requests. We discuss the applicability of this algorithm with respect to the state-of-the-art GMPLS standards, above all, the GMPLS routing extensions to OSPF-TE. By extensive simulations, we justify that the Min-phys-hop algorithm produces close-to-optimal blocking and resource consumption under almost all possible selections of input parameters, and this is regardless of the wavelength and Optical-Electrical-Optical (OEO) conversion capability present in the network.     

BGP routing policies in ISP networks

The Internet has quickly evolved into a vast global network owned and operated by thousands of different administrative entities. During this time, it became apparent that vanilla shortest path routing would be insufficient to handle the myriad operational, economic, and political factors involved in routing. ISPs began to modify routing configurations to support routing policies - goals held by the router's owner that controlled which routes were chosen and which routes were propagated to neighbors. BGP, originally a simple path vector protocol, was incrementally modified over time with a number of mechanisms to support policies, adding substantially to the complexity. Much of the mystery in BGP comes not only from the protocol complexity, but also from a lack of understanding of the underlying policies and the problems ISPs face that are addressed by these policies. In this article we shed light on goals operators have and their resulting routing policies, why BGP evolved the way it did, and how common policies are implemented using BGP. We also discuss recent and current work in the field that aims to address problems that arise in applying and supporting routing policies.     

Improving call admission policies in wireless networks

It is well known that the call admission policy can have a big impact on the performance of a wireless network. However, the nonlinear dependence of new calls and handoff calls makes the search for a better call admission policy – in terms of effective utilization – a difficult task. Many studies on optimal policies have not taken the correct dependence into consideration. As a result, the reported gains in those studies cannot be confirmed in a real network. In this paper we develop a solution to the problem of finding better call admission policies. The technique consists of three components. First, we search for the policy in an approximate reducedcomplexity model. Second, we modify the Linear Programming technique for the inherently nonlinear policysearch problem. Third, we verify the performance of the found policy in the exact, highcomplexity, analytical model. The results shown in the paper clearly demonstrate the effectiveness of the proposed technique.     

Analysis of discarding policies in high-speed networks

Networked applications generate messages that are segmented into smaller, fixed or variable size packets, before they are sent through the network. In high-speed networks, acknowledging individual packets is impractical; so when congestion builds up and packets have to be dropped, entire messages are lost. For a message to be useful, all packets comprising it must arrive successfully at the destination. The problem is therefore which packets to discard so that as many complete messages are delivered, and so that congestion is alleviated or avoided altogether. Selective discarding policies, as a means for congestion avoidance, are studied and compared to nondiscarding policies. The partial message discard policy discards packets of tails of corrupted messages. An improvement to this policy is the early message discard that drops entire messages and not just message tails. A common performance measure of network elements is the effective throughput which measures the utilization of the network links but which ignores the application altogether. We adopt a new performance measure-goodput-which reflects the utilization of the network from the application's point of view and thus better describes network behavior. We develop and analyze a model for systems which employ discarding policies. The analysis shows a remarkable performance improvement when any message-based discarding policy is applied, and that the early message discard policy performs better than the others, especially under high load. We compute the optimal parameter setting for maximum goodput at different input loads, and investigate the performance sensitivity to these parameters     

TDM policies in multistation packet radio networks

A multistation packet radio network with m stations and a finite number of nodes n that uses a conflict-free protocol to access the backbone network of stations through a shared channel is discussed. The goal is to derive an allocation of the channel time slots (time-division multiplexing cycle), so that all transmissions will be conflict-free and some measure of performance (e.g., the expected total weighted throughput, the expected weighted holding cost) will be optimized. The methodology that is used is to bound the performance and to allocate the slots according to the golden ratio policy     

我国互联互通的政策与实践

互联互通管理是基础电信业务市场引入竞争后出现的新生事物。为了打破电信行业的垄断,政府在不同的电信业务领域适度引入竞争,由于电信竞争触及了原有的运营企业在电信市场中所处的垄断、支配地位,触及了其切身利益,因而原有的运营企业对竞争、对竞争对手是不欢迎的,常常会利用其在互联互通中的重要作用向新兴的电信运营企业施加互联阻力,以此达到压制竞争对手的目的。在电信管制的诸多环节中,市场准入、号码频率审批等权力均掌握在政府手中,而互联互通的主动权则掌握在电信市场处于垄断或支配地位的运营企业手中。因此,互联互通管理是业界公认的管理难题。     

采用VC++开发的智能建筑系统集成组态软件设计

本文介绍了智能建筑集成管理系统组态软件的结构及实现方法.由于目前各知名品牌的楼控产品均支持OPC标准,故系统采用OPC技术实现不同系统的数据共享,同时提供开放的数据访问平台,从而可进一步进行如系统节能等方面的数据分析与处理.该系统基于Web平台,可实现因特网的远程监控,运用VC 编程语言可保证系统的实时控制,试运行效果良好,各项功能均运行正常.