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Design of Distributed Fault-Tolerant Industrial Network
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作者 路林吉 邵志南 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期96-99,共4页
A token-bus-based design method of the distributedfault-tolerant industrial network is presented in this pa-per.The dual-link network is of hot-redundancy.The performance of the network is also discussed.
关键词 FAULT - tolerance REDUNDANCY NETWORK diag-nosis NETWORK reconfiguration.
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Exosomes derived from microRNA-540-3p overexpressing mesenchymal stem cells promote immune tolerance via the CD74/nuclear factor-kappaB pathway in cardiac allograft
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作者 Ji-Gang He Xin-Xin Wu +3 位作者 Si Li Dan Yan Gao-Peng Xiao Fu-Gang Mao 《World Journal of Stem Cells》 SCIE 2024年第12期1022-1046,共25页
BACKGROUND Heart transplantation is a crucial intervention for severe heart failure,yet the challenge of organ rejection is significant.Bone marrow mesenchymal stem cells(BMSCs)and their exosomes have demonstrated pot... BACKGROUND Heart transplantation is a crucial intervention for severe heart failure,yet the challenge of organ rejection is significant.Bone marrow mesenchymal stem cells(BMSCs)and their exosomes have demonstrated potential in modulating T cells,dendtitic cells(DCs),and cytokines to achieve immunomodulatory effects.DCs,as key antigen-presenting cells,play a critical role in shaping immune responses by influencing T-cell activation and cytokine production.Through this modulation,BMSCs and their exosomes enhance graft tolerance and prolonging survival.AIM To explore the immunomodulatory effects of exosomes derived from BMSCs overexpressing microRNA-540-3p(miR-540-3p)on cardiac allograft tolerance,focusing on how these exosomes modulating DCs and T cells activity through the CD74/nuclear factor-kappaB(NF-κB)pathway.METHODS Rat models were used to assess the impact of miR-540-3p-enhanced exosomes on immune tolerance in cardiac allografts.MiR-540-3p expression was manipulated in BMSCs,and derived exosomes were collected and administered to the rat models post-heart transplantation.The study monitored expression levels of major histocompatibility complex II,CD80,CD86,and CD274 in DCs,and quantified CD4^(+)and CD8^(+)T cells,T regulatory cells,and cytokine profiles.RESULTS Exosomes from miR-540-3p-overexpressing BMSCs lead to reduced expression of immune activation markers CD74 and NF-κB p65 in DCs and T cells.Rats treated with these exosomes showed decreased inflammation and improved cardiac function,indicated by lower levels of pro-inflammatory cytokines(interleukin-1β,interferon-γ)and higher levels of anti-inflammatory cytokines(interleukin-10,transforming growth factorβ1).Additionally,miR-540-3p skewed the profiles of DCs and T cells towards immune tolerance,increasing the ratio of T regulatory cells and shifting cytokine secretion to favor graft acceptance.CONCLUSION Exosomes derived from BMSCs overexpressing miR-540-3p significantly enhance immune tolerance and prolong cardiac allograft survival by modulating the CD74/NF-κB pathway,which regulates activities of DCs and T cells.These findings highlight a promising therapeutic strategy to improve heart transplantation outcomes and potentially reduce the need for prolonged immunosuppression. 展开更多
关键词 Bone marrow mesenchymal stem cells Exosomes MicroRNA-540-3p Cardiac allograft Immune tolerance
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Antisense-Mediated Depletion of Tomato Chloroplast Omega-3 Fatty Acid Desaturase Enhances Thermal Tolerance 被引量:11
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作者 Xun-Yan Liu Jing-Hua Yang +2 位作者 Bin Li Xiu-Mei Yang Qing-Wei Meng 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第9期1096-1107,共12页
A chloroplast-localized tomato (Lycopersicon esculentum Mill.) ω-3 fatty acid desaturase gene (LeFADT) was isolated and characterized with regard to its sequence, response to various temperatures, and function in... A chloroplast-localized tomato (Lycopersicon esculentum Mill.) ω-3 fatty acid desaturase gene (LeFADT) was isolated and characterized with regard to its sequence, response to various temperatures, and function in antisense transgenic tomato plants. The deduced amino acid sequence had four histidine-rich regions, of which three regions were highly conserved throughout the whole ω-3 fatty acid desaturasegene family. Southern blotting analysis showed that LeFAD7was encoded by a single copy gene and had two homologous genes in the tomato genome. Northern blot showed that LeFAD7 was expressed in all organs and was especially abundant in leaf tissue. Meanwhile, expression of LeFAD7 was induced by chilling stress (4 ℃), but was inhibited by high temperature (45 ℃), in leaves. Transgenic tomato plants were produced by integration of the antisense LeFAD7DNA under the control of a CaMV35S promoter into the genome. Antisense transgenic plants with lower 18 : 3 content could maintain a higher maximal photochemical efficiency (Fv/Fm) and O2 evolution rate than wild-type plants. These results suggested that silence of the LeFAD7 gene alleviated high-temperature stress. There was also a correlation between the low content of 18 : 3 resulting from silence of the LeFAD7 gene and tolerance to high-temperature stress. 展开更多
关键词 chloroplast-localized ω-3 fatty acid desaturase gene expression thermal tolerance tomato (Lycopersicon esculentum) tomato transformation
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一种高速SERDES抖动容限的高效仿真验证方法 被引量:2
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作者 邵刚 田泽 +1 位作者 李世杰 吕俊盛 《计算机技术与发展》 2015年第7期217-220,共4页
文中针对高速SERDES总线接收端的验证提出了一种抖动容限验证方法,有效降低了流片风险。由于受温度、布线、信道寄生的影响较大,高速SERDES需要保证在恶劣信道,尤其是大的抖动干扰时仍能稳定工作,设计阶段对接收电路抗抖动特性的评估是... 文中针对高速SERDES总线接收端的验证提出了一种抖动容限验证方法,有效降低了流片风险。由于受温度、布线、信道寄生的影响较大,高速SERDES需要保证在恶劣信道,尤其是大的抖动干扰时仍能稳定工作,设计阶段对接收电路抗抖动特性的评估是一个复杂的验证过程,鲜有报道。文中基于对PCIE,SRIO,FC等信道和协议的研究,提出一种快速高效的RX端抖动容限的验证评估方法。经验证采用该模型能方便准确地评估RX的特性,经电路流片后,实际测试表明,采用该方法评估的抖动容限结果与测试结果精确符合,可在设计阶段显著优化RX的性能,并大幅降低流片的风险。 展开更多
关键词 SERDES 抖动容限 验证 CDR 时钟恢复电路
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基于数据采集的VHDL带通滤波 被引量:1
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作者 黄蕾 刘百玉 +1 位作者 白永林 欧阳娴 《计算机仿真》 CSCD 2007年第9期312-315,共4页
针对纯硬件实现RC带通滤波具有很大的局限性,而HDL(硬件描述语言)具有高层次的自上而下的设计方法,为系统硬件设计提供了更大的灵活性,具有更高的通用性,能有效地缩短设计周期,减少生产成本[1]。文中简要介绍了一种VHDL实现通带为0.1s-0... 针对纯硬件实现RC带通滤波具有很大的局限性,而HDL(硬件描述语言)具有高层次的自上而下的设计方法,为系统硬件设计提供了更大的灵活性,具有更高的通用性,能有效地缩短设计周期,减少生产成本[1]。文中简要介绍了一种VHDL实现通带为0.1s-0.4s的时域带通滤波器,该滤波器主要用于预处理数据位流,该数据位流是由同步数据传输延时补偿网络采集到的。为便于利用计算机进行1.5μs在线时序仿真,文中给出了通带为0.1μs-0.4μs的时域等效带通滤波时钟的VHDL设计实例,并利用时序矢量仿真波形初步分析了抖动容限[2],从而证实了该实例的正确与合理性。 展开更多
关键词 数据采集 超高速集成电路硬件描述语言 带通滤波 抖动容限
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容迟容断网络中基于拓扑的双时隙路由算法
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作者 王兴伟 魏永涛 +1 位作者 黄敏 王军伟 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第8期1069-1072,1095,共5页
在公交车载网络等类型的容迟容断网络中,可以依靠全部或者部分网络拓扑信息进行路由计算.提出一种基于拓扑信息的双时隙路由算法.该算法将网络周期离散为时隙,计算路由时,采用当前时隙和下一时隙(即双时隙)内均有效的路径作为候选路径,... 在公交车载网络等类型的容迟容断网络中,可以依靠全部或者部分网络拓扑信息进行路由计算.提出一种基于拓扑信息的双时隙路由算法.该算法将网络周期离散为时隙,计算路由时,采用当前时隙和下一时隙(即双时隙)内均有效的路径作为候选路径,从而保证多数业务在链路失效前完成转发.以传输延时和延时抖动率为依据,从当前和下一时隙内均有效的路径中优选路径,以容忍可预测的链路中断;通过提供备用路径,以容忍不可预测的链路中断,保证传输的可靠性和稳定性.对上述算法进行了仿真实现和性能分析,结果表明,该算法能容忍链路中断,报文递交率较高,平均传输延时较低. 展开更多
关键词 容迟容断网络 路由 拓扑信息 双时隙 延时 延时抖动率
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轮转调度下实时流量到达时间间隔抖动的容忍分析
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作者 张怡 李峭 +1 位作者 何锋 熊华钢 《电光与控制》 北大核心 2011年第3期66-68,共3页
研究了AFDX交换机在采用轮转调度策略,并保证消息传输实时性的前提下,对消息到达时间间隔抖动的容忍能力。采用实时通信中的周期性任务模型,依据实时性保证原则,推导出在已知的轮转调度策略下,交换机允许消息到达最小时间间隔,及交换机... 研究了AFDX交换机在采用轮转调度策略,并保证消息传输实时性的前提下,对消息到达时间间隔抖动的容忍能力。采用实时通信中的周期性任务模型,依据实时性保证原则,推导出在已知的轮转调度策略下,交换机允许消息到达最小时间间隔,及交换机对消息抖动的容忍度的数学表达式。最后给出在给定的实时流量下,到达时间间隔抖动容忍度的计算实例,结合算例结果分析了实际情况中容忍度的意义,即容忍度越低,消息延时越容易破坏消息的实时性。 展开更多
关键词 航空电子系统 AFDX 轮转调度 到达间隔 抖动容忍
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BEPCII次谐波聚束系统物理公差要求的研究(英文)
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作者 裴士伦 王书鸿 《强激光与粒子束》 EI CAS CSCD 北大核心 2006年第8期1349-1354,共6页
为了进一步提高束流品质并逐步采用双束加速技术,BEPCII直线加速器准备采用带有两个次谐波聚束器的双次谐波聚束系统。目前,该次谐波聚束系统的物理设计和优化已经基本完成。由于新设计的双次谐波聚束系统很不同于BEP-CII现有的聚束系统... 为了进一步提高束流品质并逐步采用双束加速技术,BEPCII直线加速器准备采用带有两个次谐波聚束器的双次谐波聚束系统。目前,该次谐波聚束系统的物理设计和优化已经基本完成。由于新设计的双次谐波聚束系统很不同于BEP-CII现有的聚束系统,因此,就要求对聚束系统中存在的各种抖动(jitter)效应重新进行研究。使用多粒子模拟计算程序PARMELA对电子枪的高压抖动和定时抖动、次谐波聚束器的相位抖动以及功率抖动、聚束器中加速电场相位以及A0加速管(俘获加速节)中加速电场相位的抖动等效应进行了研究,并最终确定了聚束系统中各部件的物理公差要求。 展开更多
关键词 物理公差 聚束系统 次谐波聚束器 抖动效应 PARMELA
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拖拉机安全控制器容错技术的研究与实现
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作者 张明明 郭富强 +1 位作者 阳俊 谭俊杰 《拖拉机与农用运输车》 2019年第3期20-22,共3页
在拖拉机安全控制器设计开发的基础上,针对开关信号抖动及CAN总线信号异常的情况进行深入分析,研究相应的容错处理技术并通过软硬件设计予以实现,以提升拖拉机安全控制器运行的稳定性及可靠性。
关键词 拖拉机安全控制器 开关信号抖动 CAN总线信号异常 容错处理技术 软硬件设计
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高速SerDes抖动成因及其测试方法分析 被引量:2
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作者 霍卫涛 邵刚 +1 位作者 李攀 李哲 《计算机光盘软件与应用》 2012年第2期67-68,共2页
高速SerDes(SERializer/DESerializer)设备在高速芯片I/O接口互联上已经占有统治性地位。然而随着串行链路速率不断提高,随之而来的抖动等因素对高速SerDes成品率构成极大威胁。本文首先对SerDes的结构进行介绍,然后对高速SerDes中信号... 高速SerDes(SERializer/DESerializer)设备在高速芯片I/O接口互联上已经占有统治性地位。然而随着串行链路速率不断提高,随之而来的抖动等因素对高速SerDes成品率构成极大威胁。本文首先对SerDes的结构进行介绍,然后对高速SerDes中信号抖动进行定性分析,最后提出了几种重要的SerDes测试方法,对高速Serdes的测试具有一定参考价值。 展开更多
关键词 高速SerDes 抖动 眼孔 jitter tolerance AC参数
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Cytokinin signaling promotes salt tolerance by modulating shoot chloride exclusion in maize 被引量:5
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作者 Pan Yin Xiaoyan Liang +6 位作者 Hanshu Zhao Zhipeng Xu Limei Chen Xiaohong Yang Feng Qin Jingbo Zhang Caifu Jiang 《Molecular Plant》 SCIE CSCD 2023年第6期1031-1047,共17页
Excessive accumulation of chloride(Cl^(-))in the aboveground tissues under saline conditions is harmful to crops.Increasing the exclusion of Cl^(-) from shoots promotes salt tolerance in various crops.However,the unde... Excessive accumulation of chloride(Cl^(-))in the aboveground tissues under saline conditions is harmful to crops.Increasing the exclusion of Cl^(-) from shoots promotes salt tolerance in various crops.However,the underlying molecular mechanisms remain largely unknown.In this study,we demonstrated that a type A response regulator(ZmRR1)modulates Cl^(-) exclusion from shoots and underlies natural variation of salt tolerance in maize.ZmRR1 negatively regulates cytokinin signaling and salt tolerance,likely by interacting with and inhibiting His phosphotransfer(HP)proteins that are key mediators of cytokinin signaling.A naturally occurring non-synonymous SNP variant enhances the interaction between ZmRR1 and ZmHP2,conferring maize plants with a salt-hypersensitive phenotype.We found that ZmRR1 undergoes degradation under saline conditions,leading to the release of ZmHP2 from ZmRR1 inhibition,and subsequently ZmHP2-mediated signaling improves salt tolerance primarily by promoting Cl^(-) exclusion from shoots.Furthermore,we showed that ZmMATE29 is transcriptionally upregulated by ZmHP2-mediated signaling under highly saline conditions and encodes a tonoplast-located Cl^(-) transporter that promotes Cl^(-) exclusion from shoots by compartmentalizing Cl^(-) into the vacuoles of root cortex cells.Collectively,our study provides an important mechanistic understanding of the cytokinin signaling-mediated promotion of Cl^(-) exclusion from shoots and salt tolerance and suggests that genetic modification to promote Cl^(-) exclusion from shoots is a promising route for developing salt-tolerant maize. 展开更多
关键词 cytokinin signaling salt tolerance high-Cl^(-)tolerance Cl^(-)transporter MAIZE
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高速串行信号接收机测试 被引量:1
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作者 万力劢 《中国集成电路》 2011年第5期74-78,93,共6页
本文讨论了高速串行信号接收机测试的必要性和方法,介绍了一种针对当前主流串行信号标准的测试仪器PeRT3。
关键词 高速串行信号 接收机测试 误码率测试 抖动容限测试 力科PeRT3
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2.5 Gbit/s光接收模块定时抖动特性实验研究
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作者 丁国庆 胡毅 《光通信研究》 北大核心 2002年第2期59-62,共4页
报告了 2 .5 Gbit/s光接收模块 3种定时抖动的实验测试结果 ,并与国际标准所允许的2 .5 Gbit/s光系统抖动指标进行了比较 ;分析和讨论了影响抖动的主要因素和改进方法 .
关键词 定时抖动 实验 光接收模块 光通信
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Optimized Three-Stage Strategy of Orderly Management of File Stream in Network Printing Workflow
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作者 Yanling LIAO Xinguang LV 《Journal of Systems Science and Information》 CSCD 2017年第1期74-87,共14页
This paper proposed the optimized three-stage strategy of orderly management of file stream in network printing workflow. In first stage the customer preflight was added to the conventional prepress preflight, which s... This paper proposed the optimized three-stage strategy of orderly management of file stream in network printing workflow. In first stage the customer preflight was added to the conventional prepress preflight, which set quick-type, general-type, stable-type and comprehensive-type preflight scheme for customers by investigating the possibility of occurrence of errors of various preflight entries and customer relevancy. Based on four types of preflight schemes, four customer preflight applications were created by using Pitstop Pro and Connector You. Customers can select one of the appropriate applications for quick preflight before delivering to reduce the probability of returning the files back for correction when errors occur in preflight. Second stage is printing enterprise prepress preflight,which proposed the concept of the prepress preflight tolerance. In addition, according to the different requirements of printing technology and quality, this paper established the prepress preflight scheme based on the printing enterprises’ tolerance for preflight error. Third stage is to manage the optimized sorting of prepress file stream. To achieve it, the SPT rule and the 0-1 programming model were adopted, time spend of preflight, printing process and post-press finishing was also taken into account.Moreover, Enfocus Switch software was applied to establish automated network printing workflow and complete the file stream sorting. Finally, the result of simulation analysis of the optimized strategy shows that the optimized three-stage strategy can effectively shorten the file processing time. 展开更多
关键词 customer preflight prepress preflight tolerance SPT rule 0-1 programming model
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Structure and dielectric properties of solid solutions Bi_(7)Ti_(4+x)WxNb_(1-2x-0.1)V_(0.1)O_(21)(x=0.1-0.4)
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作者 S.V.Zubkov 《Journal of Advanced Dielectrics》 CAS 2020年第1期48-54,共7页
The structural and electrophysical characteristics of a number of solid solutions of layered oxides of the perovskite-type Bi_(7)Ti_(4+x)WxNb_(1-2x-0.1)V_(0.1)O_(21)(x=0.1-0.4)are studied.According to X-ray powder dif... The structural and electrophysical characteristics of a number of solid solutions of layered oxides of the perovskite-type Bi_(7)Ti_(4+x)WxNb_(1-2x-0.1)V_(0.1)O_(21)(x=0.1-0.4)are studied.According to X-ray powder diffraction data,all the compounds studied are single-phase and have the structure of Aurivillius phases(m=2.5)with a rhombic crystal lattice(space group I2 cm,Z=2).Changes in tetragonal and rhombic distortions of perovskite-like layers in compounds were considered depending on their chemical composition.The temperature dependences of the relative permittivityε(T)were measured.It was shown that the Curie temperature T_(C) of the perovskite-type oxides Bi_(7)Ti_(4+x)WxNb_(1-2x-0.1)V_(0.1)O_(21)(x=0.1-0.4)linearly decreases with increasing parameter x.The activation energies of charge carriers were obtained in different temperature ranges.It was found that there are three temperature regions with very different activation energies due to the different nature of the charge carriers in the studied compounds.The effect of substitution of Nb^(5+) ions by V^(5+) ions is investigated.It was found that for a number of compounds,the substitution of niobium ions by vanadium ions led to an increase in the dielectric constant and a decrease in the dielectric loss tangent. 展开更多
关键词 Aurivilliusphases Bi_(7)Ti_(4+x)WxNb_(1-2x-0.1)V_(0.1)O_(21) Curie temperature(T_(C)) tolerance factor
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