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1.
介绍了广播电视接收机新的行业标准,以及广播电视接收机声性能测试修订的主要内容和技术背景,并重点地对音频通道的声性能测量的方法和限值要求的等内容进行了详细说明,对新标准经过半年的实际使用后的实施情况进行了分析.使行业内尽快了解新标准并推动新标准的实施.  相似文献   

2.
目前的钻井工程数据库标准历经15年,依旧发挥着积极作用,同时新技术和新需求的出现,也催化标准与时俱进。在此背景下提出扩展与深化钻井数据库标准的设计原则,进而探讨了对若干数据库技术细节的处理方法,最后指出了推进这一标准化工作的要点。从统观的角度思考新的钻井信息化建设,为行业的标准化提供参考。  相似文献   

3.
Overview of the MPEG Reconfigurable Video Coding Framework   总被引:2,自引:0,他引:2  
Video coding technology in the last 20 years has evolved producing a variety of different and complex algorithms and coding standards. So far the specification of such standards, and of the algorithms that build them, has been done case by case providing monolithic textual and reference software specifications in different forms and programming languages. However, very little attention has been given to provide a specification formalism that explicitly presents common components between standards, and the incremental modifications of such monolithic standards. The MPEG Reconfigurable Video Coding (RVC) framework is a new ISO standard currently under its final stage of standardization, aiming at providing video codec specifications at the level of library components instead of monolithic algorithms. The new concept is to be able to specify a decoder of an existing standard or a completely new configuration that may better satisfy application-specific constraints by selecting standard components from a library of standard coding algorithms. The possibility of dynamic configuration and reconfiguration of codecs also requires new methodologies and new tools for describing the new bitstream syntaxes and the parsers of such new codecs. The RVC framework is based on the usage of a new actor/ dataflow oriented language called CAL for the specification of the standard library and instantiation of the RVC decoder model. This language has been specifically designed for modeling complex signal processing systems. CAL dataflow models expose the intrinsic concurrency of the algorithms by employing the notions of actor programming and dataflow. The paper gives an overview of the concepts and technologies building the standard RVC framework and the non standard tools supporting the RVC model from the instantiation and simulation of the CAL model to software and/or hardware code synthesis.  相似文献   

4.
当半导体工业进入到超深亚微米时代后,标准单元的设计面临着新的挑战.由于亚波长光刻的使用,图形转移质量将严重下降.在这种情况下,以集成电路的可制造性作为目标的"可制造性设计"方法在标准单元设计中变得至关重要.本文分析了超深亚微米与纳米工艺条件下标准单元设计中遇到的一些典型可制造性问题,提出了相应的新设计规则和解决方案,完成了实际90nm工艺下标准单元的可制造性设计工作.同时,文中提出了包括光刻模拟、测试电路组等技术在内的单元可制造性设计和验证的流程.  相似文献   

5.
介绍了视频编码新标准———H .2 6 4中采用的几种抗误码技术 ,基于这些技术 ,新标准确保了压缩视频流在接收端的恢复质量。  相似文献   

6.
新的标准模型下基于身份的环签名方案   总被引:2,自引:0,他引:2  
该文提出了一种新的基于身份的环签名方案,并在标准模型下证明其能抵抗签名伪造攻击,且具有无条件匿名性。与现有标准模型下基于身份的环签名方案相比,新方案具有更短的公开参数,对于n个成员的环,签名长度只有n+1个群元素,签名验证需要n+1个双线性对运算,因此能更好的满足应用要求。  相似文献   

7.
A new and improved image coding standard, called JPEG2000, has been developed. JPEG2000 is the state-of-the-art image coding standard that results from the joint efforts of the International Standards Organization (ISO) and the International Telecommunications Union. In this article, we describe the most important parameters of this new standard and present several "tips and tricks" to help resolve the design tradeoffs that JPEG2000 application developers are likely to encounter in practice. The new standard outperforms the older JPEG standard by approximately 2 dB of peak signal-to-noise ratio (PSNR) for several images across all compression ratios. The JPEG2000's superiority from the previous standard largely depends on the standard's security aspects, interactive protocols and application program interfaces for network access, wireless transmission, wavelet transform, and embedded block coding with optimal truncation (EBCOT).  相似文献   

8.
《Ad hoc Networks》2008,6(6):970-984
Wireless mesh networking based on 802.11 wireless local area network (WLAN) has been actively explored for a few years. To improve the performance of WLAN mesh networks, a few new communication protocols have been developed in recent years. However, these solutions are usually proprietary and prevent WLAN mesh networks from interworking with each other. Thus, a standard becomes indispensable for WLAN mesh networks. To meet this need, an IEEE 802.11 task group, i.e., 802.11s, is specifying a standard for WLAN mesh networks. Although several standard drafts have been released by 802.11s, many issues still remain to be resolved. In order to understand what performance can be expected from the existing framework of 802.11s standard and what functionalities shall be added to 802.11s standard to improve performance, a detailed study on the existing 802.11s standard is given in this paper. The existing framework of 802.11s standard is first presented, followed by pointing out the challenging research issues that still exist in the current 802.11 standard. The purpose of this paper is to motivate other researchers to develop new scalable protocols for 802.11 wireless mesh networks.  相似文献   

9.
In this paper, a new and simple predictive coding algorithm for video compression and multimedia communication for different network applications is investigated. This algorithm is called semi‐hexagonal absolute moment block truncation coding (SH‐AMBTC). It enjoys better objective and subjective qualities over the standard square shaped AMBTC. This technique based on the prediction of the bit‐map of the middle frames in a sequence from the bit‐map of the end frames (the first and the last frames in the group). It is of very low complexity comparing to the standard algorithm MPEG. The new algorithm adds no complexity to the existing AMBTC algorithm. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

10.
The new IEEE standard 802.15.4 shows promise to bring ubiquitous networking into our lives, at least technically. Unlike other standards targeting high- or moderate-data-rate applications, IEEE 802.15.4 is a global standard designed for low-data-rate, low power consumption, and low-cost applications. This so-called enabling standard brings many simple, originally standalone devices into networks, and thus not only open the door to an enormous number of new applications, but also add values to many other existing applications. In this article we first present a few application scenarios to show the potential extent to which the new standard can affect our lives, and then give an overview of the standard, focusing on its feasibility and functions in establishing ubiquitous networks. We also outline some quantitative results from our experiments so as to have a better view of the standard.  相似文献   

11.
UPS系统结构和性能分类   总被引:3,自引:0,他引:3  
本文根据新的国际标准IEC 62040-3的规定,介绍了双变换UPS、市电交互UPS、冷备用UPS等三种标准单机UPS系统和各种冗余UPS系统,闸述了UPS按性能分类的新方法.  相似文献   

12.
Image compression systems that exploit the properties of the human visual system have been studied extensively over the past few decades. For the JPEG2000 image compression standard, all previous methods that aim to optimize perceptual quality have considered the irreversible pipeline of the standard. In this work, we propose an approach for the reversible pipeline of the JPEG2000 standard. We introduce a new methodology to measure visibility of quantization errors when reversible color and wavelet transforms are employed. Incorporation of the visibility thresholds using this methodology into a JPEG2000 encoder enables creation of scalable codestreams that can provide both near-threshold and numerically lossless representations, which is desirable in applications where restoration of original image samples is required. Most importantly, this is the first work that quantifies the bitrate penalty incurred by the reversible transforms in near-threshold image compression compared to the irreversible transforms.  相似文献   

13.
New layout overlay techniques have been developed based on standard image correlation techniques to support failure analysis in modern microelectronic devices, which are critical to analyze because they are realized in new technologies using sub-μm design rules, chemical mechanical polishing techniques CMP and auto-routing design techniques. As the new techniques are realized as an extension of a standard CAD-navigation software using standard image format “TIFF”, which is available at all modern FA-equipment, these techniques can be used for all modern failure analysis methods. Examples of application are given for circuit modification using Focused Ion Beam (FIB), for supporting preparation from the backside and for fault localization using emission microscopy.  相似文献   

14.
The IEEE 802.16 standard is a Broadband Wireless Access (BWA) technology which offers Quality of Service (QoS) support to different types of applications. This standard defines the physical (PHY) and medium access control (MAC) layers. Its MAC layer defines different types of QoS mechanisms to support various types of applications, being the multicast polling one of these mechanisms. Under this mechanism, based on a contention process, every connection competes to gain access to the channel in order to place its bandwidth requests. In this paper, we propose a new signalling mechanism, called Requests Per Service Flow (RPSF), to reduce the contention phase in the frame. Additionally, we undertake a comparison of this new method with respect to other mechanisms. The simulation results show that our new proposal outperforms other mechanisms recently reported in the literature, in terms of throughput and end-to-end delay.  相似文献   

15.
The scope of this brief is to introduce a novel geometry for circular series connected multilevel inductors. The idea is to improve the overlapping of the different metal layers that form the integrated inductor to maximize the magnetic flux shared by them and so the inductance. The performance of this new geometry has been compared with the conventional one, using Agilent HFSS field solver. After that, two multilevel inductors using this new geometry have been fabricated in a standard 0.6 μm three-metal CMOS process and measured  相似文献   

16.
Two seed deposition hardware are compared in this paper: a standard Self Ionized Plasma (SIP) standard chamber and a new generation chamber allowing Cu deposition and re-sputtering simultaneously. TEM characterizations exhibits better features coverage for new seed generation thank to process fine tuning. It induces defectivity improvement and void density is reduced with new hardware. Furthermore, reliability performances are improved without degrading parametrical results.  相似文献   

17.
结合湖南烟草商业系统应用集成项目实践,从数据集成、流程集成、界面集成三个方面入手,提出了基于J2EE标准的应用集成架构,并阐述了门户应用层、数据交换平合与数据集成平台、工作流平台的作用及相关的技术标准和集成规范,探讨了“在统一规划下,以应用集成架构为蓝图、以一套完整的技术标准与规范体系为依据,以一个有效的集成操作方案与系统软件支撑平台为手段”的应用系统间的集成、整合和信息共事方法.  相似文献   

18.
It is shown that the standard theories of avalanche statistics for two-carrier impact ionization by Tager, McIntyre, and Personick only deal with processes for which the number of possible ionizations is very large. On the contrary, it is believed that in many modern devices the numberNof possible ionizations is finite and perhaps even very small (N = 1-5). A complete theory for this case is developed, using a new statistical approach, referred to as the "method of recurrent generating functions." The rather complex detailed expressions so obtained contain as special cases the result forN = 1given by Lukaszek et al., and the results of the above mentioned standard theories forN = infinthese theories thus retain asymptotic validity. Computer plots of the new results indicate that the standard theories overestimate the noise of the avalanche process; this may explain exceedingly low noise data, as reported recently by Goedbloed and Smeets. Finally, for the asymptotic case a complete evaluation is made of the distribution for the output particle population. Previous results by McIntyre are fully corroborated.  相似文献   

19.
铯原子喷泉的飞行时间信号   总被引:2,自引:0,他引:2  
应用激光冷却与囚禁的铯原子喷泉是新一代的频率基准。报告了冷原子云上抛信号的序列测量 ,发表了飞行时间 (TOF)信号的基本估算公式 (估算原子云温度和TOF峰值信号强度 ) ,讨论了理论计算和实验测量的比较  相似文献   

20.
A new voltage-mode ternary CMOS static latch circuit is presented. Realized in a standard digital CMOS fabrication technology, this latch uses only enhancementmode NMOS and PMOS transistors with single threshold voltage values. No special transistor threshold voltages or depletion-mode devices are required. Experimental data verify the ternary latch's operation. Fastest and slowest onchip setup and hold times are simulated to be approximately 1.9 ns and 3.4 ns, respectively, using data for standard 2 micron digital CMOS fabrication technologies.  相似文献   

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