This paper proposes a new primary lazy update protocol, PTCS （Primary Transaction Commit Schedule）. In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary trans...This paper proposes a new primary lazy update protocol, PTCS （Primary Transaction Commit Schedule）. In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary transactions are committed according to the serializable primary transaction schedule. PTCS protocol can guarantee serializability if the data copy graph contains no directed circles. It can also be ex tended to eliminate all requirements on the data copy graph. Compared to earlier works, PTCS protocol not only imposes a much weaker requirement on the data placement, but also avoids the deadlock caused by transaction waits and extra message overhead. The performance experiments show that the degradation of the performance caused by the replica man- agement of the PTCS protocol is tolerable.展开更多
Colorectal cancers(CRCs) display a wide variety of genomic aberrations that may be either causally linked to their development and progression, or might serve as biomarkers for their presence. Recent advances in rapid...Colorectal cancers(CRCs) display a wide variety of genomic aberrations that may be either causally linked to their development and progression, or might serve as biomarkers for their presence. Recent advances in rapid high-throughput genetic and genomic analysis have helped to identify a plethora of alterations that can potentially serve as new cancer biomarkers, and thus help to improve CRC diagnosis, prognosis, and treatment. Each distinct data type(copy number variations, gene and micro RNAs expression, Cp G island methylation) provides an investigator with a different, partially independent, and complementary view of the entire genome. However, elucidation of gene function will require more information than can be provided by analyzing a single type of data. The integration of knowledge obtained from different sources is becoming increasingly essential for obtaining an interdisciplinary view of large amounts of information, and also for cross-validating experimental results. The integration of numerous types of genetic and genomic data derived from public sources, and via the use of ad-hoc bioinformatics tools and statistical methods facilitates the discovery and validation of novel, informative biomarkers. This combinatory approach will also enable researchers to more accurately and comprehensively understand the associations between different biologic pathways, mechanisms, and phenomena, and gain new insights into the etiology of CRC.展开更多
甚高频数据交换-卫星部分(VHF Data Exchange-Satellite,VDE-SAT)是下一代海事通讯系统甚高频数据交换系统(VHF Data Exchange System,VDES)的关键组成部分,用于实现航海船站与海事卫星以及航海船站间的相互通信和数据传输,其链路层接...甚高频数据交换-卫星部分(VHF Data Exchange-Satellite,VDE-SAT)是下一代海事通讯系统甚高频数据交换系统(VHF Data Exchange System,VDES)的关键组成部分,用于实现航海船站与海事卫星以及航海船站间的相互通信和数据传输,其链路层接入性能对于VDES的实际应用效果有着重要影响。针对当前实际应用中航海船站随机接入VDES系统容易出现峰值吞吐量较低和线性工作区较短的问题,该文在深入分析国际电信联盟制定的ITU-R M.2092标准规范和航海船站接入VDE-SAT的技术特性,以及现有无线网络随机接入协议的基础上,提出一种适用于VDE-SAT的基于功率分集和直接序列扩频的竞争解决分集时隙ALOHA(Power Diversity and Direct Sequence Spread Spectrum CRDSA,PD-DS-CRDSA)方法。该方法在传统无线网络竞争解决分集时隙ALOHA(Contention Resolution Diversity Slotted ALOHA,CRDSA)算法的基础上,通过采用多副本技术和连续干扰消除技术提高数据包成功解码率,同时引入功率分集和直接序列扩频技术,在一定程度上消除了传统CRDSA算法容易出现的“环路”问题。实验仿真结果表明,该方法在提高VDE-SAT随机接入的峰值吞吐量,延长线性工作区和降低数据包碰撞率等方面有较好表现。展开更多
基金Supported by Visiting Scholar Foundation of KeyLabin University and National Lab of Switching Technology and Tele-communication Networks ([2000]123)
文摘This paper proposes a new primary lazy update protocol, PTCS （Primary Transaction Commit Schedule）. In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary transactions are committed according to the serializable primary transaction schedule. PTCS protocol can guarantee serializability if the data copy graph contains no directed circles. It can also be ex tended to eliminate all requirements on the data copy graph. Compared to earlier works, PTCS protocol not only imposes a much weaker requirement on the data placement, but also avoids the deadlock caused by transaction waits and extra message overhead. The performance experiments show that the degradation of the performance caused by the replica man- agement of the PTCS protocol is tolerable.
基金Supported by Associazione Italiana per la Ricerca sul CancroGrants No.10529 and No.12162funds obtained throughan Italian law that allows taxpayers to allocate 0.5%share of theirincome tax contribution to a research institution of their choice
文摘Colorectal cancers(CRCs) display a wide variety of genomic aberrations that may be either causally linked to their development and progression, or might serve as biomarkers for their presence. Recent advances in rapid high-throughput genetic and genomic analysis have helped to identify a plethora of alterations that can potentially serve as new cancer biomarkers, and thus help to improve CRC diagnosis, prognosis, and treatment. Each distinct data type(copy number variations, gene and micro RNAs expression, Cp G island methylation) provides an investigator with a different, partially independent, and complementary view of the entire genome. However, elucidation of gene function will require more information than can be provided by analyzing a single type of data. The integration of knowledge obtained from different sources is becoming increasingly essential for obtaining an interdisciplinary view of large amounts of information, and also for cross-validating experimental results. The integration of numerous types of genetic and genomic data derived from public sources, and via the use of ad-hoc bioinformatics tools and statistical methods facilitates the discovery and validation of novel, informative biomarkers. This combinatory approach will also enable researchers to more accurately and comprehensively understand the associations between different biologic pathways, mechanisms, and phenomena, and gain new insights into the etiology of CRC.
文摘甚高频数据交换-卫星部分(VHF Data Exchange-Satellite,VDE-SAT)是下一代海事通讯系统甚高频数据交换系统(VHF Data Exchange System,VDES)的关键组成部分,用于实现航海船站与海事卫星以及航海船站间的相互通信和数据传输,其链路层接入性能对于VDES的实际应用效果有着重要影响。针对当前实际应用中航海船站随机接入VDES系统容易出现峰值吞吐量较低和线性工作区较短的问题,该文在深入分析国际电信联盟制定的ITU-R M.2092标准规范和航海船站接入VDE-SAT的技术特性,以及现有无线网络随机接入协议的基础上,提出一种适用于VDE-SAT的基于功率分集和直接序列扩频的竞争解决分集时隙ALOHA(Power Diversity and Direct Sequence Spread Spectrum CRDSA,PD-DS-CRDSA)方法。该方法在传统无线网络竞争解决分集时隙ALOHA(Contention Resolution Diversity Slotted ALOHA,CRDSA)算法的基础上,通过采用多副本技术和连续干扰消除技术提高数据包成功解码率,同时引入功率分集和直接序列扩频技术,在一定程度上消除了传统CRDSA算法容易出现的“环路”问题。实验仿真结果表明,该方法在提高VDE-SAT随机接入的峰值吞吐量,延长线性工作区和降低数据包碰撞率等方面有较好表现。
