Golay encoding/decoding via BCH-Hamming

The (24, 12;8) extended Golay Code can be generated as a 6 × 4 binary matrix from the (15, 11;3) BCH-Hamming Code, represented as a 5 × 3 matrix, by adding a row and column, both of odd or even parity. The odd parity case provides the additional 12^th dimension. Furthermore, any three columns and five rows of the 6 × 4 Golay form a permuted BCH- Hamming (15, 11;3) Code. Using the single-error correction of the BCH-Hamming Code, it is possible to decode in a primitive combinatoric fashion all three error patterns. Single- and double-error correction is almost immediate.     

Architectural support for designing fault-tolerant open distributedsystems

An overview of the main techniques for designing fault-tolerant software and hardware systems is provided. The important features of the building blocks (computers, memories, buses, etc.) that can support an efficient implementation of fault-tolerant open distributed systems (FTODSs) are identified. Taking into account the features of these building blocks, an organization for FTODS is proposed. A distributed voting algorithm and a two-level hierarchy for permanent memory are key elements in this scheme. The algorithms needed for transferring files and synchronizing the concurrent activities of the computing modules and for recovery-are ISO standard protocols. Low-level voting and recovery algorithms that can run as a layer of software above the operating system make the open distributed system an attractive environment for applying fault-tolerant techniques     

A new approach for designing fault-tolerant WDM networks

In recent years, path protection has emerged as a widely accepted technique for designing survivable WDM networks. This approach is attractive, since it is able to provide bandwidth guarantees in the presence of link failures. However, it requires allocating resources for backup lightpaths, which remain idle under normal fault-free conditions. In this paper, we introduce a new approach for designing fault-tolerant WDM networks, based on the concept of survivable routing. Survivable routing of a logical topology ensures that the lightpaths are routed in such a way that a single link failure does not disconnect the network. When a topology is generated using our approach, it is guaranteed to have a survivable routing. We further ensure that the logical topology is able to handle the entire traffic demand after any single link failure. We first present an ILP that optimally designs a survivable logical topology, and then propose a heuristic for larger networks. Experimental results demonstrate that this new approach is able to provide guaranteed bandwidth, and is much more efficient in terms of resource utilization, compared to both dedicated and shared path protection.     

fMRI的视觉神经信息编解码方法综述

视觉神经信息编解码旨在利用功能磁共振成像(functional magnetic resonance imaging,fMRI)等神经影像数据研究视觉刺激与大脑神经活动之间的关系。编码研究可以对神经活动模式进行建模和预测,有助于脑科学与类脑智能的发展;解码研究可以对人的视知觉状态进行解译,能够促进脑机接口领域的发展。因此,基于fMRI的视觉神经信息编解码方法研究具有重要的科学意义和工程价值。本文在总结基于fMRI的视觉神经信息编解码关键技术与研究进展的基础上,分析现有视觉神经信息编解码方法的局限。在视觉神经信息编码方面,详细介绍了基于群体感受野估计方法的发展过程;在视觉神经信息解码方面,首先,按照任务类型将其划分为语义分类、图像辨识和图像重建3个部分,并深入阐述了每个部分的代表性研究工作和所用的方法。特别地,在图像重建部分着重介绍了基于深度生成模型(主要包括变分自编码器和生成对抗网络)的简单图像、人脸图像和复杂自然图像的重建技术。其次,统计整理了该领域常用的10个开源数据集,并对数据集的样本规模、被试个数、刺激类型、研究用途及下载地址进行了详细归纳。最后,详细介绍了视觉神经信息编解码模...     

A program nucleus for encoding and decoding calendar dates

A novel algorithm and subroutine is presented for encoding and decoding calendar dates. For encoding a numeric calendar date in the form day, month, year is converted into an integer variable in the range between 2(15) -1 and -2(15). With decoding this integer variable is converted into numeric day, month and year. The algorithm performs very quickly and takes only 7 lines of FORTRAN code for encoding and decoding respectively.     

Unified parallel encoding and decoding algorithms for Dandelion-like codes

The Dandelion-like codes are eight bijections between labeled trees and strings of node labels. The literature contains optimal sequential algorithms for these bijections, but no parallel algorithms have been reported. In this paper the first parallel encoding and decoding algorithms for Dandelion-like codes are presented. Namely, a unique encoding algorithm and a unique decoding algorithm, which when properly parameterized, can be used for all Dandelion-like codes, are designed. These algorithms are optimal in the sequential setting. The encoding algorithm implementation on an EREW PRAM is optimal, while the efficient implementation of the decoding algorithm requires concurrent reading.     

Covariance consistency methods for fault-tolerant distributed data fusion

This paper presents a general, rigorous, and fault-tolerant framework for maintaining consistent mean and covariance estimates in an arbitrary, dynamic, distributed network of information processing nodes. In particular, a solution is provided that addresses the information deconfliction problem that arises when estimates from two or more different nodes are determined to be inconsistent with each other, e.g., when two high precision (small covariance) estimates place the position of a particular object at very different locations. The challenge is to be able to resolve such inconsistencies without having to access and exploit global information to determine which of the estimates is spurious. The solution proposed in this paper is called Covariance Union.     

A new algorithm for encoding and decoding the Hilbert order

An iterative algorithm is described, based on the replication process of the Hilbert matrix, for encoding and decoding the Hilbert order. The time complexity of the proposed algorithm is smaller than those published previously, and the space complexity is bounded by a constant. Moreover, the new algorithm has a wider applicability when compared with existing algorithms for certain machine‐word lengths. A new variant of the Hilbert curve is suggested to overcome a shortcoming of the traditional Hilbert curve for the mapping problem. The proposed coding algorithms for the traditional Hilbert curve are also applicable to the new variant without increasing the time and space complexities. Copyright © 2006 John Wiley & Sons, Ltd.     

Two-branch encoding and iterative attention decoding network for semantic segmentation

Neural Computing and Applications - Deep convolutional neural networks(DCNNs) have shown outstanding performance in semantic image segmentation. In this paper, we propose a two-branch encoding and...     

LDPC码在LTE-Advanced中的应用及编译码算法研究

通过分析LTE-Advanced系统中LDPC码的校验矩阵构造方法,找到了与LTE兼容的低码率扩展方法,针对该扩展方法提出了两种优化的编码算法,并在MATLAB平台的仿真测试环境下,通过最小和译码算法进行译码。测试结果表明,LDPC码非常适合用于高速传输系统中,仿真对比得到的最优修正值使译码性能得到改善,能满足高精度的数字信号传输需要。为LTE-Advanced系统的信道编解码器的硬件设计提供了一套有效的编译码算法方案,具有较好的实用价值。     

红外遥控器解码软件设计及应用

传统的红外遥控器解码,需要预知发射端红外编码格式,不同的编码格式软件不通用,可移植性差。通过对遥控器红外信号的采集、分析,提出基于AT87C52单片机外部中断,利用HS0038红外线接收器的红外遥控器的解码软件的设计及其应用,可以在不掌握遥控器的编码格式的情况下,破译每个键的红外编码,进而将其扩展为单片机的键盘系统。其程序通用性好,装置集成化高,可以方便地应用于其他红外遥控接收装置。     

Studies and advances on joint source-channel encoding/decoding techniques in flow media communications

Joint source-channel coding/decoding (JSCC/JSCD) techniques in flow media communications have become a state-of-the-art and one of the challenging research subjects in the spatial communication area. They have great application prospective and deep impact in various manned space flights, satellite missions, mobile radio communications and deep-space explorations. In the last few years, there have been influential achievements in JSCC/JSCD studies. This paper aims at an introduction to the basic principles o...     

Grid-based switch fabrics: a new approach in designing fault-tolerant ATM switches

ATM is the switching and multiplexing technology chosen to be used in the implementation of B-ISDN, because of its superiority in fast packet switching. However, the use of ATM switches with large number of input and output ports have been proven to be a bottleneck in wide area ATM networks. In this paper, we propose a new space-division grid-based ATM architecture with fault tolerant characteristics and minimal number of switching elements (SE's).     

一种用于时空体元编解码存储的低计算量优化方法

针对时空网格体对象的编解码占用存储空间大的问题,提出了一种用于时空体元编解码存储的低计算量优化方法。首先以十六叉树索引结构为基础,构建了时空网格体元编解码的数学模型,实现体元对象标识和时空位置索引,并借助3DGIS的自动编解码方法,实现了时空网格体元对象编解码存储表示的换算;其次,采用伽罗华有限域理论,构建了网格体元的二进制编码矩阵和存储的低计算量优化算法,实现了体元对象编解码存储过程中的优化计算;最后,以某矿山的矿床空间块体数据为例,对网格体元编解码模型、存储表示换算以及低计算量优化算法进了实际应用,并与八叉树索引结构的Morton码进行比较和分析,结果表明：该方法可有效降低30%的编解码存储计算量,提高了存储网格体元对象的时空效率。     

基于注意力机制的多层次编码和解码的图像描述模型

图像描述任务是图像理解的一个重要分支,它不仅要求能够正确识别图像的内容,还要求能够生成在语法和语义上正确的句子.传统的基于编码器-解码器的模型不能充分利用图像特征并且解码方式单一.针对这些问题,提出一种基于注意力机制的多层次编码和解码的图像描述模型.首先使用Faster R-CNN(Faster Region-base...     

A new efficient encoding/decoding procedure for the design of a supply chain network with genetic algorithms

Supply chain network (SCN) design is a strategic issue which aims at selecting the best combination of a set of facilities to achieve an efficient and effective management of the supply chain. This paper presents an innovative encoding–decoding procedure embedded within a genetic algorithm (GA) to minimize the total logistic cost resulting from the transportation of goods and the location and opening of the facilities in a single product three-stage supply chain network. The new procedure allows a proper demand allocation procedure to be run which avoids the decoding of unfeasible distribution flows at the stage of the supply chain transporting products from plants to distribution centers. A numerical study on a benchmark of problems demonstrates the statistical outperformance of the proposed approach vs. others currently available in literature in terms of total supply chain logistic cost saving and reduction of the required computation burden to achieve an optimal design.     

Multi-Objective Artificial Bee Colony for designing multiple genes encoding the same protein

The improvement of protein expression levels represents one of the most important goals in synthetic biology. In order to accomplish it, a promising and widely-used strategy lies on integrating multiple genes that encode the subject protein into an organism genome. This important task, however, is affected by several challenging issues. Firstly, the integration of highly similar sequences can potentially induce homologous recombination, a negative effect that implies a reduction in the number of genes effectively integrated. This is the reason why it is important to design multiple protein-coding sequences (also named CDSs) that are as different as possible, between both different CDSs and different subsequences within the same CDS. Additionally, codon usage frequencies in these CDSs should be as highly adapted to the organism as possible. Therefore, this task involves different and conflicting objectives that must be optimized, thus being suitable to be tackled as a multi-objective optimization problem. In this work, we design and implement the algorithm MOABC (Multi-Objective Artificial Bee Colony) to solve the problem of designing multiple CDSs that encode the same protein, considering three objectives to be optimized. The experimental evaluation herein performed suggests that MOABC is able to obtain relevant results, showing statistically significant improvements over the ones found in the literature.     

一种新的Turbo码译码迭代停止准则

介绍了Turbo码编码与译码原理。针对传统停止迭代准则译码耗费硬件资源的不足,提出了利用外部信息结合交叉熵迭代停止准则作为新的迭代停止准则算法。仿真分析结果显示：新的迭代停止准则可在不同的信噪比情况下,保证迭代次数适中并确保译码性能的稳定,应用该算法既可提高无线通信的数据传输质量、减小系统传输时延,又可最大限度地节约硬件资源。