CRC校验在USB控制器设计中的实现

USB协议提供了强大的错误处理功能,其中包括对传送数据进行CRC校验。发送器在位填充前产生CRC,接收器在位填充去除后对CRC进行译码。如果CRC译码失败,忽略该包。本文首先分析USB中CRC校验的数学原理,然后给出硬件设计方案,包括串行CRC设计和并行CRC设计。     

网络协议中CRC码的递推算法及其软件生成

本文给出了一种快速的CRC递推算法，并给出了计算网络协议中CRC－16码和CRC－CCITT码的程序代码。     

字节型CRC算法分析与实现

循环冗余码校验CRC是计算机网络通信中最常采用的数据校验方法之一,CRC方法能够很好地降低数据传输的误码率。本文分析了CRC算法的原理和CRC算法的校验规则,针对字节型CRC算法,提出一种直观、紧凑、易于理解的表驱动字节型算法描述,给出了严格的数学证明,通过实例详细演绎了算法的实现过程。同时,设计了相关的类汇编语言CRC-ITU算法,简要讨论了使用F(x)/G(x)的直接余式作为监督码的方法。     

CRC校验及其软件实现

论述了CRC的数学原理、在数据通信中的作用,提出了用 8031汇编语言实现CRC校验的程序设计,阐述了该技术在测控系统中的应用.     

逆序CRC编解码算法及在DS18B20中的应用

循环冗余校验CRC码是检错与纠错能力极强的线性分组码,在通信与测控领域应用广泛.本文提出了逆序CRC信息单元编码算法,即以包含若干位的信息块为单元计算CRC的方法,进行了详细的数学推导,给出了编码算法流程图.分析了CRC的解码算法并给出了解码算法流程图.在讨论了DS18820的CRC程序流程图的基础上,给出了在keil μ Vision8.08a环境下调试通过的KeilC51程序.     

基于FPGA的CRC算法的实现

CRC校验是一种数据通信中广泛应用的检错方法。在多种通信协议的帧结构中有一个16位或32位的FCS,就是利用CRC编码保证数据帧的无误传输。本文阐述了CRC算法的基本原理,并基于实际系统需要,在FPGA中实现了CRC算法。     

CAN协议中CRC编码的硬件实现

针对CAN协议中提出的串行CRC检验原理,给出其硬件实现方法及具体实现时应需注意的技术问题,给出了RTL级的VHDL代码。为了提高CRC编码的生成速度和CRC检验的效率,介绍了CRC检验的并行原理,并针对CAN协议中CRC编码的生成多项式推导出了8位并行CRC编码的逻辑关系式。最后对串行和并行两种实现方式进行了性能对比,并给出了为满足CAN协议而进行CRC编码时应注意的问题。     

CRC算法的应用理论研究

本文从理论上系统的研究了循环冗余校验(CRC)码的原理和性质,解决了在实际应用中经常碰到的如何设置寄存器的初始值及如何选取生成多项式的问题;同时,通过分析不同长度下算法的性能差异提出了CRC算法对校验数据的长度没有限制的观点。最后,提出了CRC逆运算的概念。     

10G以太网系统中的并行CRC编解码器的设计

为了解决10G以太网接入系统中大规模并行CRC编码器的设计问题,提出了矩阵法、代入法、流水线法等三种设计方法。以此为基础,给出了10G以太网接入系统中CRC编码器的实现方案。具体计算表明,在10G以太网接入系统中采用直接并行的CRC编码器是可行的。直接并行设计的CRC编码器已经通过了EDA模拟,并成功地应用于10G以太网接入系统中。     

基于CAN总线的改进CRC校验算法设计

CAN总线上的数据传输采用高效、可靠的差错检测方法——CRC校验算法。首先详细介绍了CRC校验算法的原理,并针对普通的CRC校验方法依然存在漏检事件的问题,设计了一种改进的CRC校验方法。经实验验证,该方法可以提高校验的检漏率,适用于可靠性要求较高的工业控制系统中。     

CRC算法在计算机网络通信中的应用

在计算机网络通信中，为了降低数据通信线路传输的误码率，可以采用一种差错检测控制——循环冗余码校验（CRC）。介绍了CRC算法的原理、CRC算法的校验规则、CRC算法分析、CRC算法程序设计。由于CRC算法采用软件校验的方法，不需要设计另外的硬件电路，校验速度非常快，提高了计算机网络通信的速度和报文传输的准确性。     

基于FPGA的CRC并行算法研究与实现

循环冗余校验(CRC)算法广泛应用于通信领域以提高数据传输的可靠性.针对通信过程中常用的CRC校验,介绍了CRC的编码和解码原理,分析了CRC的经典算法的实现过程,并在此基础上提出了基于FPGA的CRC并行处理算法.采用VHDL语言对算法完成建模与实现,并以Altera公司开发的EDA工具QuartusII8.0作为编译、仿真平台进行了仿真验证.电路的综合结果表明,该方法具有更少的资源占用量和更高的工作效率.     

Identification of cancer-associated proteins by proteomics and downregulation of β-tropomyosin expression in colorectal adenoma and cancer

Elucidating the molecular mechanism underlying the development of adenoma, the major precursor lesion of colorectal cancer (CRC), would provide a basis for early detection, prevention as well as treatment of CRC. Using the highly sensitive 2-D DIGE method coupled with MS, we identified 24 differentially expressed proteins in adenoma tissues compared with matched normal colonic mucosa and CRC tissues. Fifteen proteins were downregulated and three proteins were upregulated in adenoma tissues when compared with individual-matched normal colonic mucosa. Five proteins were downregulated, while one protein was upregulated in adenoma tissues when compared with matched CRC tissues. A protein, β-tropomyosin (TM-β), recently suggested to be a biomarker of esophageal squamous carcinoma, was downregulated in both adenoma and CRC tissues. Additionally, the reduction in the level of TM-β in adenoma and CRC tissues was further validated by Western blotting (p<0.05) and RT-PCR (p<0.001). Our findings suggest that downregulation of TM-β is involved in the early development of CRC and that differentially expressed proteins might serve as potential biomarkers for detection of CRC.     

An application of the 2-nitrobenzenesulfenyl method to proteomic profiling of human colorectal carcinoma: A novel approach for biomarker discovery

In the development of novel biomarkers, the proteomic approach is advantageous because using it the cancer-associated proteins can be directly identified. We previously developed a 2-nitrobenzenesulfenyl (NBS) method to improve quantitative proteome analysis. Here, we applied this method to proteomic profiling of colorectal carcinoma (CRC) to identify novel proteins with altered expression in CRC. Each pair of tumor and normal tissue specimens from 12 CRC patients was analyzed, and approximately 5000 NBS-labeled paired peaks were quantified. Peaks with altered signal intensities (>1.5-fold) and occurring frequently in the samples (>70%) were selected, and 128 proteins were identified by MS/MS analyses as differentially expressed proteins in CRC tissues. Many proteins were newly revealed to be CRC related; 30 were reported in earlier studies of CRC. Six proteins that were up-regulated in CRC (ZYX, RAN, RCN1, AHCY, LGALS1, and VIM) were further characterized and validated by Western blot and immunohistochemistry. All six were found to be CRC-localized, either in cancer cells or in stroma cells near the cancer cells. These results indicate that the proteins identified in this study are novel candidates for CRC markers, and that the NBS method is useful in proteome mining to discover novel biomarkers.     

Proteomics-based identification of HSP60 as a tumor-associated antigen in colorectal cancer

Patients with cancer frequently develop autoantibodies. The identification of tumor autoantigens may have utility in early cancer diagnosis and immunotherapy. In this study, we used serological proteomics analysis (SERPA) to identify tumor proteins that elicit humoral response in colorectal cancer (CRC). The CRC cell line HCT116 was used as a source of proteins for 2-DE and subsequent Western blot analysis in which individual serum from patients with CRC was analyzed for autoantibodies. An autoantibody against HSP60 identified by MS was detected in 13 out of 25 patients with CRC and 1 out of 15 healthy subjects. In addition, the HSP60 expressions in tumor tissues collected from 40 patients with CRC were assessed by immunohistochemistry, and serum specimens from 100 patients with cancer and 30 healthy controls were screened for antibody titer to HSP60 by ELISA. The results showed that expressions of HSP60 in tumor tissue and serum antibody titer to HSP60 were significantly higher in patients with CRC than in healthy subjects. Thus, we conclude that the SERPA is an excellent assay for the identification of tumor-associated antigens and tumor markers. The detection of HSP60 may have clinical utility in CRC screening, diagnosis, and immunotherapy.     

10G以太网接口并行CRC校验的一种简化算法

在10G以太网接口设计中,64位并行数据的CRC校验是其设计难点之一,常见的一些方法在对其进行CRC32校验时,会因为以太网帧不一定结束在64比特边界,导致进行校验处理时需要同时包含8,16,24,32,40,48,56,64位的校验单元。本文提出了一种只需64位的校验单元即可实现其CRC校验的方法。     

一种用于UHF RFID系统循环冗余校验的新算法

基于ISO18000—6C协议标准的UHFRFID系统中的读写器和标签之间的通信,采用CRC5和CRC16循环冗余校验。目前UHFRFID系统中,收发数据的循环冗余校验都采用按位校验法,本文根据已有的循环冗余查表校验法,提出一种适用于ISO18000—6C协议标准的新型循环冗余校验算法,极大地提高了循环冗余校验效率,非常适合用于嵌入式实时系统通信。实验结果表明,该算法将CRC5校验的效率提高了17％,将CRC16校验的效率提高了27％以上。     

Quantitative mass spectrometry for colorectal cancer proteomics

This review documents the uses of quantitative MS applied to colorectal cancer (CRC) proteomics for biomarker discovery and molecular pathway profiling. Investigators are adopting various labeling and label-free MS approaches to quantitate differential protein levels in cells, tumors, and plasma/serum. We comprehensively review recent uses of this technology to examine mouse models of CRC, CRC cell lines, their secretomes and subcellular fractions, CRC tumors, CRC patient plasma/serum, and stool samples. For biomarker discovery these approaches are uncovering proteins with potential diagnostic and prognostic utility, while in vitro cell culture experiments are characterizing proteomic and phosphoproteomic responses to disrupted signaling pathways due to mutations or to inhibition of drugable enzymes.