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1.
当今社会通信及高速通信数据网的飞速发展,数据的交换、处理和存储技术得到了广泛的应用,人们对数据传输和存储系统的可靠性提出了越来越高的要求。本系统介绍在纠错编解码中很常用的一种方法——线性分组码,并通过单片机编程实现这种纠错码,模拟通信过程中出现的错误并纠正错误。在这个系统中利用单片机编程实现线性分组码的编码和伴随式译码过程。  相似文献   

2.
量子纠错码是实现量子通信和量子计算的有效编码方案,如何构造高性能的量子纠错码是量子纠错理论最基本的研究课题之一.量子常循环码具有良好的代数结构,可以通过量子线性移位寄存器进行编译,在未来量子通信系统中有着广泛的应用前景.本综述将介绍量子常循环码的构造方法,揭示经典常循环码与量子纠错码之间的联系,阐述经典常循环码在量子MDS码和纠缠辅助量子MDS码中的应用.  相似文献   

3.
通过改进传统线性分组码的伴随式译码算法,提出了一种低复杂度的列表译码算法,该算法通过组合线性分组码校验矩阵中权重较小的列向量进行译码并正确计算出各码字元素的软输出信息,应用该算法可以构造乘积码迭代译码器,比较其他同类算法,该算法不仅性能较好,适用码型范围较广,而且可以根据具体情况在译码复杂度和译码性能两者之间做出折衷选择,分析和仿真结果表明,该译码算法在误码性能和译码复杂度方面都优于传统的乘积码失代译码算法,能够有效应用于通信系统中实现纠错,具有很大的实际应用价值。  相似文献   

4.
循环码是线性分组码的一个重要子类 ,有严密的数学结构 ,具有纠、检错能力 ,且编码、解码用软件、硬件都容易实现。研究了循环码实现的方法和应用原理 ,结果表明 ,将该方法应用于前向纠错方式中 ,能大大提高通信质量  相似文献   

5.
循环码是线性分组码的一个重要子类,有严密的数学结构,具有纠、检错能力,且编码、解码用软件,硬件都容易实现,研究了循环码实现的方法和应用原理,结果表明,将该方法应用于前向纠错方式中,能大大提高通信质量。  相似文献   

6.
好的纠错码在很大程度上依赖于抽象代数的有力的和完美的结构,线性空间理论就是纠错编码的重要基础之一.本文将系统地研究线性空间的扩展和距离特征,并给出了几个应用实例.结果表明:本文的研究结果对于纠错码的构造是十分有用的.  相似文献   

7.
在光盘存储中,纠错编解码技术的应用是实现数据可靠存储的重要保证。讨论了在光盘存储中应用得最为广泛的两种纠错码技术:RS编码和RSPC编码,针对光盘应用建立了多种误差模型,仿真了纠错码技术的作用过程,比较了RS码与RSPC码在纠错能力上的差别。  相似文献   

8.
单片机与PC机通信中的纠错编码   总被引:2,自引:0,他引:2  
PC机与单片机构成的上、下位机分布式控制系统是一种常见的工业控制系统,它结合了单片机对实时数据采集、控制以及PC机对图形显示、数据处理的优点.介绍一电火花成型机数控系统中,单片机串口与PC机通信过程中的纠错编码.采用线性分组码进行编码,用伴随式译码.由于加工过程中,电火花的电极与工件之间的火花对于弱电控制系统本身就是一个干扰源,采用该介绍的纠错编码后,通信效果很好.  相似文献   

9.
RS(Reed—Solomon)码是具有很强纠错能力的线性分组码,广泛应用于各种通信和存储系统中。文中设计的译码器采用修正的欧几里德算法(MEA),并在实现中采用公共项提取算法有效地优化了乘法器,以迭代、复用等方法降低了RS码译码硬件实现的复杂度。并用Verilog-HDL语言实现了RS(255,239)码的译码器各个模块的功能。  相似文献   

10.
本文探讨了神经网络与纠错编码之间的关系,将神经网络引入分组码软判决译码中.通过映射变换α→(Q-1)-2α,建立了分组码软判决译码与神经网络之间的关系;证明了线性分组码软判决最小距离译码等效于寻找对应的神经网络能量函数最大值,神经网络优化算法可用于分组码软判决译码中.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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