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基于主动网络的多路径流量均衡模型研究

计算机工程与应用 2009年第14期45卷 107-110页

作者：钱洁邱航吴晓晖湖北汽车工业学院信息管理系湖北十堰442002 电子科技大学计算机学院成都610054

现有网络中到达某一目的地址的流量一般集中在最优路径上,这使得网络资源利用不均衡,拥塞不可避免,而传统网络体系结构很难实现流量均衡。利用主动网络节点的协作分布式计算能力给出了一种多路径的流量均衡模型,该模型包括多路径输出流... 详细信息

现有网络中到达某一目的地址的流量一般集中在最优路径上,这使得网络资源利用不均衡,拥塞不可避免,而传统网络体系结构很难实现流量均衡。利用主动网络节点的协作分布式计算能力给出了一种多路径的流量均衡模型,该模型包括多路径输出流量优化分配、输入带宽优化分配、拥塞抑制等算法,实现了流量与资源的均衡配置。实验证明该模型提高了网络链路的利用率,避免或减少了网络拥塞的发生,整个网络性能得到了提高。

关键词：主动网络多路径路由流量均衡

CB/WPU导电复合材料在有机蒸汽中的气敏响应特性初探

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中山大学学报（自然科学版） 2006年第6期45卷 62-66页

作者：赵斌符若文章明秋张斌中山大学化学与化学工程学院∥聚合物复合材料及功能材料教育部重点实验室广东广州510275

采用乳液共混法制得了炭黑/水溶性聚氨酯(CB/WPU)气敏导电复合材料。复合材料在饱和溶剂蒸汽中的最大响应随着溶剂的介电常数的增大而减小。在非极性饱和溶剂蒸汽中,没有观察到负蒸汽系数(NVC)效应,其最大电阻响应达到106倍以上;而在极... 详细信息

采用乳液共混法制得了炭黑/水溶性聚氨酯(CB/WPU)气敏导电复合材料。复合材料在饱和溶剂蒸汽中的最大响应随着溶剂的介电常数的增大而减小。在非极性饱和溶剂蒸汽中,没有观察到负蒸汽系数(NVC)效应,其最大电阻响应达到106倍以上;而在极性饱和溶剂蒸汽中,经过一段时间之后,复合材料的电阻将接近于一个平衡值,该平衡值的大小随着溶剂的介电常数的增加而减小,溶剂本身的导电性是导致CB/WPU复合材料在极性饱和溶剂蒸汽中出现NVC效应的主要原因。而在非饱和蒸汽中,复合材料在低压纯蒸汽条件下的最大响应高于在低压蒸汽和空气混合气氛条件下的最大响应,复合材料在低压纯蒸汽下没有NVC效应;然而在低压蒸汽和空气混合气氛中,复合材料在极性和非极性溶剂蒸汽中均存在NVC效应,这主要是由于复合材料吸收溶剂蒸汽后,环境压力诱导聚氨酯链段结构松弛引起的。

关键词：炭黑水溶性聚氨酯气敏性负蒸汽系数效应

Modulation of morphine antinoceptive tolerance in bone cancer pain rats by P2X7 purinoceptor

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Modulation of morphine antinoceptive tolerance in bone cance...

中国神经科学学会第十届全国学术会议

作者： Hui LI Zhi-Qi ZHAO Yu-qiu zhang Institute of Neurobiology Institutes of Brain Science and State Key Laboratory of Medical NeurobiologyFudan University

Bone cancer pain is the most severe chronic pain,and morphine is the most effective ***,long-term morphine therapy produces morphine antinociceptive *** far,studies on morphine tolerance are mostly carried out in normal animals,despite that the clinical morphine antinociceptive tolerance occurs only in patients with chronic ***,chronic pathological pain is quite different from normal physiological pain in *** it is more meaningful to study the mechanisms of morphine tolerance in chronic pain animal *** plays an important role in the development of both chronic pain and morphine *** the firsr time,we investigate the role of P2X7 purinoceptor-mediated the activation of spinal microghal p38/MAPK signaling pathway proinflammatory cytokines（***-lβ and IL-18） and astrocytic products（e.g.D-Serine） release,and hypersensitivity of spinal dorsal horn neurons in morphine tolerance in a rat model of bone cancer *** data showed that the chronic morphine treatment for10 days resulted in a significant loss of analgesic potency in both mechanical and thermal nociceptive tests in rats suffered from bone cancer *** expression levels of P2X7R,Ibal-1,IL-18 and IL-lβ in the spinal dorsal horn were remarkably increased,both in bone cancer rats and chronic morphine treated na（i|¨）ve ***,in chronic morphine treated bone cancer rats,spinal Ibal-1 and IL-18 levels were much lower than bone cancer rats without chronic morphine treatment and naive rats chronic with morphine *** results suggest that in chronic pathological pain status,the mechanism of morphine tolerance is more complicated.

关键词： bone cancer pain morphine tolerance P2X7R

Towards Link-disjoint paths under multiple additive QoS constraints

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Towards Link-disjoint paths under multiple additive QoS cons...

2008 the IET 2ND International Conference on Wireless,Mobile & Multimedia Networks

作者： Ke Xiong Zheng-ding qiu Hong-ke zhang Institute of Information Science Beijing Jiaotong University School of Electronics and Information Engineering Beijing Jiaotong University

Finding disjoint paths between a source and destination node pair under quality of service(QoS) constraints is a significant scheme for improving both the network survivability and the QoS *** paper proposed a new algorithm, which aims to find a pair of link-disjoint paths that each of them satisfies two or more additive *** algorithm is on the basis of SAMCRA[1][2]and searches solutions according to the varied composition forms of the exact *** and simulations show that our scheme is capable of getting feasible solutions and optimal solutions with higher probabilities than existing approaches.

关键词： Link-disjoint path QoS routing survivability

Analytical solution for evaluating deformation response of existing metro tunnel due to excavation of adjacent foundation pit

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Journal of Central South University 2021年第6期28卷 1888-1900页

作者： qiu Ju-tao JIANG Jie ZHOU Xiao-jun zhang Yue-feng PAN Ying-dong Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China College of Civil Engineering and Architecture Guangxi UniversityNanning 530004China

The excavation of foundation pit generates soil deformation around existing metro tunnel with shield driving method,which may lead to the deformation of tunnel *** is a challenge to evaluate the deformation of shield tunnel accurately and take measures to reduce the tunnel upward displacement as much as possible for geotechnical engineers.A new simplified analytical method is proposed to predict the longitudinal deformation of existing metro tunnel due to excavation unloading of adjacent foundation pit in this ***,the additional stress of soils under vertical axisymmetric load in layered soil is obtained by using elastic multi-layer ***,the metro tunnel is regarded as a Timoshenko beam supported by Winkler foundation so that the shear effect of tunnels can be taken into *** additional stress acting on the tunnel due to excavation unloading in layered soil are compared with that in homogeneous ***,the effectiveness of the analytical solution is verified via two actual ***,parametric analysis is conducted to investigate the responses of the metro tunnel by considering such factors as the variation of subgrade coefficient,offset distance from the excavation center to tunnel longitudinal axis as well as equivalent shear *** proposed method can be used to provide theoretical basis for similar engineering project.

关键词： metro tunnel simplified analytical method additional stress Timoshenko beam Winkler foundation

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互补色小波域图像质量盲评价方法

电子学报 2019年第4期47卷 775-783页

作者：陈扬李旦张建秋复旦大学信息科学与工程学院智慧网络与系统研究中心和电子工程系上海200433

图像色彩空间的RGB通道具有密切的关系,图像质量的改变会改变这样的关系.然而传统图像质量评价方法大多基于灰度图像统计特性,忽略了颜色通道间关系信息.为充分利用颜色信息,本文基于新近提出的互补色小波变换提出一种图像质量盲评价方... 详细信息

图像色彩空间的RGB通道具有密切的关系,图像质量的改变会改变这样的关系.然而传统图像质量评价方法大多基于灰度图像统计特性,忽略了颜色通道间关系信息.为充分利用颜色信息,本文基于新近提出的互补色小波变换提出一种图像质量盲评价方法.文章建立了图像互补色域自然场景统计、多尺度和方向性能量分布等模型.分析表明:这些模型不仅涵盖了传统灰度方法所能描述的信息,而且还能借助于互补色来有效表示彩色图像各通道之间的信息联系,提供表征图像质量的一组高效特征.基于这些特征,我们提出的图像质量盲评价的方法能有效提取图像的失真统计特征,能给出与人眼主观评价图像质量结果保持高度一致、优于现有文献报道盲方法、且可与非盲(全参考)方法相比拟的评价结果.

关键词：图像质量评价无参考互补色小波彩色图像

Electrochemical Behavior of Eu(Ⅲ) and U(Ⅵ) in 1-butyl-3-methylimidazolium

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Electrochemical Behavior of Eu(Ⅲ) and U(Ⅵ) in 1-butyl-3-me...

作者： zhang qiu-yue HE Hui HUANG Xiao-hong

The electrochemical behavior of Eu and UO in l-butyl-3-methylimidazolium chlorid ([BMIM]Cl) has been investigated by cyclic voltammetry and chronopotentiometry,*** electrochemical window of[BMIM]C1 is -1.7-0.80 V(***/AgCl),when the working electrode is glassy carbin *** of Eu in[BMIM]Cl takes place through a single step one-electron transfer to Eu,which is quasi-reversible *** diffusion coefficient of Eu in[BMIM]Cl

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胡塞尔的科学观研究

东北大学学报（社会科学版） 2011年第4期13卷 289-294页

作者：张秋成东北大学科学技术哲学研究中心辽宁沈阳110819

现象学的创始人胡塞尔在《欧洲科学危机和超验现象学》一书中集中阐述了他的科学观。胡塞尔认为自然科学为自己提出的任务和研究方法是不可靠的,因而缺乏真正的科学性。他对此的解释是,自然科学不但丧失了自明性的直接来源——生活世界... 详细信息

现象学的创始人胡塞尔在《欧洲科学危机和超验现象学》一书中集中阐述了他的科学观。胡塞尔认为自然科学为自己提出的任务和研究方法是不可靠的,因而缺乏真正的科学性。他对此的解释是,自然科学不但丧失了自明性的直接来源——生活世界的意义,而且正因为这种丧失,导致自然科学彻底忘却了自明性的最终来源——人的超验意识。深入研究胡塞尔的科学观,能够使我们认清自然科学的本质,看到自然科学的局限性,有效地抵制科学至上主义和物质至上主义;也有助于我们恢复对理性主义的信仰,并且在这种理性主义的指导下认真思考和实践人类生活的真正目的和意义。

关键词：现象学自明性科学哲学胡塞尔的科学观

Associations of shift work and sleep problems with symptomatic COVID-19 infection

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Associations of shift work and sleep problems with symptomat...

中国睡眠研究会第十四届全国学术年会

作者： Hanman qiu Lulu Yang Hongliang Feng Jihui zhang The Affiliated Brain Hospital of Guangzhou Medical University Guangdong Provincial People's Hospital

Background: Previous evidence indicates the sleep and circadian disruption is essential in the regulation of immune function, and shift workers and individuals with sleep problems are speculated to be associated with the risk of COVID-19 infection. Therefore, we aimed to investigate the associations of shift work and sleep problems with symptomatic COVID-19 infection in a large population-based cohort. Methods: This was a population-based cohort study based on the UK biobank, and 421373 participants resident in England and recruited between 2006 and 2010 were included. Exposures including shift work and sleep problems were obtained. Main outcome was testing results of COVID-19(March 16, 2020 to May 31, 2020). Logistic regression analysis was ***: A total of 1470(0.35%) were positive for COVID-19 infection. Among paid employers or self-employers, the frequency and type of shift work [sometimes: OR = 1.95, 95% CI: 1.57-2.43, usually or always: OR = 2.34, 95% CI: 1.94-2.81;day shift: OR = 1.98, 95% CI: 1.61-2.44, night shift: OR = 2.35, 95% CI: 1.94-2.84] were associated with the risk of COVID-19 infection after adjustment for demographics, behavioral factors, as well as mental and medical comorbidity. Daytime sleepiness was weakly associated with increased risk of infection [sometimes: OR = 1.22, 95% CI: 1.08-1.38;often: OR = 1.19, 95% CI: 0.91-1.56] in final model. No associations of sleep duration, insomnia symptoms, chronotype, and snoring with COVID-19 infection were found in final model. Sensitivity analyses recruiting 6100 participants with test results for COVID-19 infection confirmed similar ***: Shift work may enhance susceptibility towards symptomatic COVID-19 infection. Besides, daytime sleepiness may also be weakly associated with symptomatic COVID infection. Therefore, preventive strategies targeting at COVID-19 infection may set priority to those shift workers.

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