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1.
The knowledge of turbo code's minimum Hamming distance (dmin) and its corresponding codeword multiplicity (Amin) is of a great importance because the error correction capability of a code is strongly tied to the values of dmin and Amin. Unfortunately, the computational complexity associated with the search for dmin and Amin can be very high, especially for a turbo code that has high dmin value. This paper introduces some useful properties of turbo codes that use structured interleavers together with circular encoding. These properties allow for a significant reduction of search space and thus reduce significantly the computational complexity associated with the determination of dmin and Amin values. © 2014 The Authors. International Journal of Communication Systems published by John Wiley & Sons, Ltd.  相似文献   
2.
ABSTRACT

In recent times, the applications of multimedia are rising in a greedy mode and hence the amount of video transactions is also increasing exponentially. This has shouted great demands on effective models on video encoding and also for reducing the transmission channel congestion. This research work introduces a managing technique termed weighted encoding for High-Efficiency Video Coding (HEVC). HEVC, also termed as MPEG-H Part 2 and H.265 is a video compression standard that is widely utilized AVC (H.264 or MPEG-4 Part 10). When compared to AVC, HEVC grants double the ratio of data compression at a similar level of quality of the video or considerably enhanced video quality at a similar bit rate. This work intends to optimize the weight that adopted in HEVC for encoding. For this, this paper proposes a new Iterative based propagation update in the water wave Optimization Algorithm (IPU-WWO), which is the improved form of Water wave Optimization (WWO). The performance of proposed IPU-WWO is compared over other conventional methods like Artificial Bee Colony (ABC), Firefly (FF), Particle Swarm Optimization (PSO) and Genetic Algorithm (GA) with respect to Peak Signal to Noise Ratio (PSNR). By doing the encoding process, it minimizes the video size with perceptually better quality video or PSNR.  相似文献   
3.
宋玉  崔晓燕 《信息技术》2006,30(11):57-60
WCDMA作为第三代移动通信系统的主流标准,能够提供多种类型的多媒体服务。为了实现各种用户平面数据的传输,系统会提前通过控制平面对所需的无线资源进行分配。由于配置过程是通过接口之间发送控制平面应用协议消息来实现的,因此能否正确有效地对信令消息进行编解码成为保证系统稳定工作的关键因素。3GPP标准中,ASN.1语言被用来描述接口信令消息。首先简要介绍了WCDMA系统结构以及主要接口协议,重点描述了ASN.1存在的意义及其编解码规则,最后给出了基于ASN.1的开发环境下应用层网络协议的开发流程。  相似文献   
4.
钟卫平 《光通信技术》2006,30(11):58-61
分析光折变三维存储器的机理,探讨了光折变三维存储器的编码方式、光折变材料的选择及存储技术,阐述了其产业化进程.  相似文献   
5.
本文主要讨论了精梳工序和普梳工序对集聚纺纱线质量和加工效率影响的测试结果。  相似文献   
6.
The purpose of this study is to examine the current standard fracture toughness test procedure to determine if there could be an easier method to get a JIc value from the test record. The current method for determining JIc involves a detailed computational and construction procedure. The objective in this study is to simplify the analysis for the determination of JIc. The results of this study show that the load and displacement record for a fracture toughness test can be used to directly estimate a JQ value, a provisional value for fracture toughness, JIc. The J value taken at the maximum load point can be used along with an adjustment factor to estimate a JQ value. This JQ estimate is close to the one obtained from the construction procedure of ASTM Standard E 1820. When a unit‐sized specimen is tested, that is, a specimen with a width of 50 mm and a thickness of 25 mm the maximum load point provides a direct estimate of JQ. Other sizes require a size adjustment factor, which is simply a square root relationship between the width of the test specimen and a unit width. The proposed new method of estimating JQ is simple in concept and requires a minimum number of calculations. It appears to produce values of JQ which are comparable to those obtained from the ASTM E1820 construction procedure and may produce less scatter.  相似文献   
7.
彩色PDP用玻璃基板   总被引:4,自引:0,他引:4  
本文讨论了彩色PDP现用钠钙玻璃的热稳定性,指出由于这种玻璃在热处理过程中易变形和收缩,因而不适合作大面积彩色PDP基板材料,介绍了彩色PDP基板玻璃的制造方法和特点。最后介绍了日本旭硝子公司和美国康宁公司各自为彩色PDP新开发的玻璃基板材料PD200和CS25。  相似文献   
8.
提出了一种用双边带深侧槽的小尺寸圆形紧凑拉伸试样评定核压力容器(RPV)钢断裂韧性的单试作试验方法,给出了用该方法测定的两个厂家生产的核压力容器用A508CL3钢的断裂韧性参数,还与Charpy试样的试验结果及大尺寸标准试样的试验结果进行了比较。研究结果表明:用双边带深侧槽的小尺寸R-CT试样测得的断裂韧性值比相同恻槽深度预制疲劳裂纹Charpy试样的测试值更接近有效断裂韧性值,所以,用于核压力容器断裂韧性的监测是可行的。  相似文献   
9.
Two important elements in problem solving are the abilities to encode relevant task features and to combine multiple actions to achieve the goal. The authors investigated these 2 elements in a task in which gorillas (Gorilla gorilla) and orangutans (Pongo pygmaeus) had to use a tool to retrieve an out-of-reach reward. Subjects were able to select tools of an appropriate length to reach the reward even when the position of the reward and tools were not simultaneously visible. When presented with tools that were too short to retrieve the reward, subjects were more likely to refuse to use them than when tools were the appropriate length. Subjects were proficient at using tools in sequence to retrieve the reward. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Two experiments involving 99 undergraduate participants sought to examine the influence of mood states on encoding speed within lexical decision and pronunciation tasks. Mood states were measured naturalistically in Experiment 1 and manipulated in Experiment 2. Stimuli consisted of nouns representing useful (e.g., food) and nonuseful (e.g., lint) objects. Mood states had no implications for initial encoding speed. However, when the same words were presented a 2nd time (i.e., repeated), happy individuals displayed a tendency to encode useful words faster than nonuseful ones. Thus, mood states influenced repetition priming on the basis of stimulus valence. The authors propose that happiness sensitizes individuals to useful or rewarding objects, which in turn creates a stronger memory trace for such stimuli in the future. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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