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Non-invasive assessment of barrier integrity and function of the human gut 被引量:18
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作者 Joep Grootjans Geertje Thuijls +3 位作者 Froukje Verdam Joep PM Derikx Kaatje Lenaerts Wim A Buurman 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2010年第3期61-69,共9页
Over the past decades evidence has been accumulating that intestinal barrier integrity loss plays a key role in the development and perpetuation of a variety of disease states including inflammatory bowel disease and ... Over the past decades evidence has been accumulating that intestinal barrier integrity loss plays a key role in the development and perpetuation of a variety of disease states including inflammatory bowel disease and celiac disease,and is a key player in the onset of sepsis and multiple organ failure in situations of intestinal hypoperfusion,including trauma and major surgery.Insight into gut barrier integrity and function loss is important to improve our knowledge on disease etiology and pathophysiology and contributes to early detection and/or secondary prevention of disease.A variety of tests have been developed to assess intestinal epithelial cell damage,intestinal tight junction status and consequences of intestinal barrier integrity loss,i.e.increased intestinal permeability.This review discusses currently available methods for evaluating loss of human intestinal barrier integrity and function. 展开更多
关键词 INTESTINAL INTEGRITY INTESTINAL BARRIER func- tion INTESTINAL permeability MARKERS
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Beneficial Effects of Delayed Opening the Infarct - related Artery on Late Phase Left Ventricular Function in Acute Anterior Myocardial Infarction
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作者 马礼坤 余华 +5 位作者 黄向阳 褚俊 冯克福 丁晓梅 严激 顾统元 《South China Journal of Cardiology》 CAS 2004年第2期71-74,79,共5页
Objectives To assess the effect of delayed opening the infarct - related artery (IRA) by percutanous coronary intervention (PCI) on the late phase left ventricular function after acute ante- rior myocardial infarction... Objectives To assess the effect of delayed opening the infarct - related artery (IRA) by percutanous coronary intervention (PCI) on the late phase left ventricular function after acute ante- rior myocardial infarction. Methods 64 patients with initial Q - wave anterior myocardial infarction and the infarct - related arteries were total occluded conformed by angiogram at 2 to 14 days after onset were divided into successful PCI group and control group ( not re- ceiving PCI or the IRA not re - opened). 2 - DE was performed at early phase ( about 3 weeks) , 2 and 6 months after onset of AMI respectively to detect the left ventricular function and left ventricular wall motion ab- normality (VWMA). The total congestive heart failure events were recorded during 6 months follow-up. Re- sults VWMA scores, left ventricular ejection frac- tion (LVEF) , left ventricular end - diastolic and end - systolic volume indices ( LVEDVI and LVDSVI) were similar in 2 groups at early phase and 2 months. There were no differences between early phase and 2 months in each group too. VWMA scores and LVEF did not changed at 6 months in each group compared with the early phase and 2 months ( P > 0. 05 ). But LVEDVI and LVESVI were significantly smaller in the successful PCI group than in the control group (P < 0.01, P < 0. 05). The congestive heart failure events were taken place in 19% of patients in control group com- pared with 2% in successful PCI group ( P > 0. 05 ). Conclusions Although the infarct size does not changed, delayed opening the IRA has beneficial effect to the late phase left ventricular dilatation after acuteanterior myocardial infarction. 展开更多
关键词 Acute myocardial infarction Per- cutanous coronary intervention Left ventricular func- tion
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考虑星间链路的星地时间同步与上注调度的启发式算法 被引量:3
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作者 张忠山 王沛 +1 位作者 贺仁杰 龙运军 《全球定位系统》 2012年第5期38-45,共8页
通过描述全球导航卫星系统基于星间链路的星地时间同步与上注任务过程,分析了基于星间链路的星地时间同步与上注任务约束复杂、星地链路资源紧缺等特点。在此基础上建立了任务调度模型,提出了基于规则的多阶段启发式算法,将出入境卫星... 通过描述全球导航卫星系统基于星间链路的星地时间同步与上注任务过程,分析了基于星间链路的星地时间同步与上注任务约束复杂、星地链路资源紧缺等特点。在此基础上建立了任务调度模型,提出了基于规则的多阶段启发式算法,将出入境卫星与非出入境卫星任务按小时分步调度,设计了总体调度流程,并给出了算法流程中每一步的启发式规则。最后,设计了三个具有代表性的算例并进行测试,结果证明了该方法的有效性。 展开更多
关键词 全球导航卫星系统 星间链路 星地时间同步与上注 调度 启发式算法
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运筹学在复杂网络社团结构分析中的应用 被引量:5
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作者 章祥荪 《运筹与管理》 CSSCI CSCD 北大核心 2013年第5期1-11,共11页
社团结构研究是复杂网络这一前沿领域中的重要问题,同运筹学有着密切的关联。本文介绍了传统社团结构问题的基本定义,以及最近十年通过应用运筹学理论对该问题的研究进展。这些进展包括启发式模型,到随后的概率优化模型,以及组合优化模... 社团结构研究是复杂网络这一前沿领域中的重要问题,同运筹学有着密切的关联。本文介绍了传统社团结构问题的基本定义,以及最近十年通过应用运筹学理论对该问题的研究进展。这些进展包括启发式模型,到随后的概率优化模型,以及组合优化模型。通过这些介绍,说明了运筹学方法论和基本工具在复杂系统研究中所起到的重要作用。 展开更多
关键词 复杂网络 社团结构 运筹学 启发式模型 概率优化模型 组合优化模型
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一种用于图象配准的或图最佳搜索算法 被引量:2
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作者 钟春香 梁志辉 《华中理工大学学报》 CSCD 北大核心 1991年第3期37-41,共5页
本文在分析研究图象配准中的SSDA法的基础上,提出一种用于图象配准的或图最佳搜索算法,该法将窗口图及基准图的子图划分为n块,形成完整的有序或图,使图象配准问题变为用或图最佳优先搜索策略求最短路径问题,实现图象配准。实验结果表明... 本文在分析研究图象配准中的SSDA法的基础上,提出一种用于图象配准的或图最佳搜索算法,该法将窗口图及基准图的子图划分为n块,形成完整的有序或图,使图象配准问题变为用或图最佳优先搜索策略求最短路径问题,实现图象配准。实验结果表明,该算法控制简单,易于实现,比传统的直接算法计算量少,试验效果好。 展开更多
关键词 图象配准 或图最佳搜索 启发函数
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联用二维数据黑色体系的多组份解析与直观推导式渐进特征投影法 被引量:2
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作者 梁逸曾 《湖南大学学报(自然科学版)》 EI CAS CSCD 1995年第1期61-69,共9页
本文首先对黑色分析体系化学计量学解析方法的发展历史作了简要回顾,为对现存各方法的适应性进行评价,着重讨论了联用色谱二维数据的重要特性。在此基础上,对直观推导式渐进特征投影法的主要思路进行了较详尽剖析。列出几种不同的,... 本文首先对黑色分析体系化学计量学解析方法的发展历史作了简要回顾,为对现存各方法的适应性进行评价,着重讨论了联用色谱二维数据的重要特性。在此基础上,对直观推导式渐进特征投影法的主要思路进行了较详尽剖析。列出几种不同的,现仍不能为已有方法所有效解析之体系,以期引起化学计量学家们的注意。 展开更多
关键词 多组份分析 黑色分析体系 投影 色谱分析
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求解两级定位-路径问题的人工鱼群算法 被引量:2
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作者 陈久梅 《计算机工程与设计》 CSCD 北大核心 2014年第7期2520-2525,共6页
提出城市货物配送系统中的两级定位-路径问题,建立该问题的两下标车流模型,引入一种高效启发式搜索策略-路径重连,设计求解该问题的人工鱼群算法。采用不同规模大小的两级定位-路径问题算例进行求解,将求解结果与人工蜂群算法进行比较... 提出城市货物配送系统中的两级定位-路径问题,建立该问题的两下标车流模型,引入一种高效启发式搜索策略-路径重连,设计求解该问题的人工鱼群算法。采用不同规模大小的两级定位-路径问题算例进行求解,将求解结果与人工蜂群算法进行比较。比较结果表明,该算法能有效求解两级定位-路径问题,在平均解及最差解的质量方面比人工蜂群算法更优。 展开更多
关键词 两级定位-路径问题 启发式算法 人工鱼群算法 路径重连 配送
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基于深度强化学习的网络攻击路径规划方法 被引量:2
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作者 高文龙 周天阳 +1 位作者 赵子恒 朱俊虎 《信息安全学报》 CSCD 2022年第5期65-78,共14页
攻击路径规划对实现自动化渗透测试具有重要意义,在现实环境中攻击者很难获取全面准确的网络及配置信息,面向未知渗透测试环境下的攻击路径规划,提出了基于深度强化学习的攻击路径规划方法。首先,对渗透测试问题的状态空间和动作空间进... 攻击路径规划对实现自动化渗透测试具有重要意义,在现实环境中攻击者很难获取全面准确的网络及配置信息,面向未知渗透测试环境下的攻击路径规划,提出了基于深度强化学习的攻击路径规划方法。首先,对渗透测试问题的状态空间和动作空间进行形式化描述,引入信息收集动作增强对环境的感知能力。然后,智能体通过与环境的自主交互进行学习,寻找最大化长期收益的最优策略,从而指导攻击者进行路径规划。当前深度强化学习算法应用于攻击路径规划存在适应性不强和收敛困难等问题,限制了其处理复杂渗透测试环境的能力。智能体在训练初期通过盲目探索得到的动作序列在维度迅速增长时质量会急剧下降,有时很难完成目标,而且低质量的动作序列大量积累会导致算法不收敛甚至神经元死亡。针对此问题,本文提出的深度强化学习算法在DDQN算法的基础上增加了路径启发信息和深度优先渗透的动作选择策略。路径启发信息充分利用历史经验,在训练初期对智能体的学习过程加以引导,深度优先渗透的动作选择策略在一定程度上对动作空间进行了剪枝,加速智能体的学习过程。最后,通过与其他深度强化学习算法在相同实验条件下的对比,验证了本文算法收敛速度更快,运行时间缩短30%以上。 展开更多
关键词 深度强化学习 路径启发信息 深度优先渗透的动作选择策略 攻击路径规划
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Improved artificial bee colony algorithm with mutual learning 被引量:7
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作者 Yu Liu Xiaoxi Ling +1 位作者 Yu Liang Guanghao Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期265-275,共11页
The recently invented artificial bee colony (ABC) al- gorithm is an optimization algorithm based on swarm intelligence that has been used to solve many kinds of numerical function optimization problems. It performs ... The recently invented artificial bee colony (ABC) al- gorithm is an optimization algorithm based on swarm intelligence that has been used to solve many kinds of numerical function optimization problems. It performs well in most cases, however, there still exists an insufficiency in the ABC algorithm that ignores the fitness of related pairs of individuals in the mechanism of find- ing a neighboring food source. This paper presents an improved ABC algorithm with mutual learning (MutualABC) that adjusts the produced candidate food source with the higher fitness between two individuals selected by a mutual learning factor. The perfor- mance of the improved MutualABC algorithm is tested on a set of benchmark functions and compared with the basic ABC algo- rithm and some classical versions of improved ABC algorithms. The experimental results show that the MutualABC algorithm with appropriate parameters outperforms other ABC algorithms in most experiments. 展开更多
关键词 artificial bee colony (ABC) algorithm numerical func- tion optimization swarm intelligence mutual learning.
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Attribute measure recognition approach and its applications to emitter recognition 被引量:10
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作者 GUANXin HEYou YIXiao 《Science in China(Series F)》 2005年第2期225-233,共9页
关键词 attribute measure emitter recognition D-S evidence theory basic probability assignment func- tion.
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Combined heat and power economic dispatch problem using the invasive weed optimization algorithm 被引量:4
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作者 T. JAYABARATHI Afshin YAZDANI V. RAMESI T. RAGHUNATHAN 《Frontiers in Energy》 SCIE CSCD 2014年第1期25-30,共6页
Cogeneration units which produce both heat and electric power are found in many process industries. These industries also consume heat directly in addition to electricity. The cogeneration units operate only within a ... Cogeneration units which produce both heat and electric power are found in many process industries. These industries also consume heat directly in addition to electricity. The cogeneration units operate only within a feasible zone. Each point within the feasible zone consists of a specific value of heat and electric power. These units are used along with other units which produce either heat or power exclusively. Hence the economic dispatch problem for these plants optimizing the fuel cost is quite complex and several classical and meta-heuristic algo- rithms have been proposed earlier. This paper applies the invasive weed optimization algorithm which is inspired by the ecological process of weed colonization and distribu- tion. The results obtained have been compared with those obtained by other methods earlier and showed a marked improvement over earlier ones. 展开更多
关键词 combined heat and power (CHP) economicdispatch meta-heuristic algorithm invasive weed optimiza-tion COGENERAtion
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EVANS FUNCTIONS AND INSTABILITY OF A STANDING PULSE SOLUTION OF A NONLINEAR SYSTEM OF REACTION DIFFUSION EQUATIONS
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作者 Linghai Zhang 《Annals of Applied Mathematics》 2016年第1期79-101,共23页
In this paper, we consider a nonlinear system of reaction diffusion equa- tions arising from mathematical neuroscience and two nonlinear scalar reaction diffusion equations under some assumptions on their coefficients... In this paper, we consider a nonlinear system of reaction diffusion equa- tions arising from mathematical neuroscience and two nonlinear scalar reaction diffusion equations under some assumptions on their coefficients. The main purpose is to couple together linearized stability criterion (the equivalence of the nonlinear stability, the linear stability and the spectral sta- bility of the standing pulse solutions) and Evans functions to accomplish the existence and instability of standing pulse solutions of the nonlinear system of reaction diffusion equations and the nonlinear scalar reaction diffusion equa- tions. The Evans functions for the standing pulse solutions are constructed explicitly. 展开更多
关键词 nonlinear system of reaction diffusion equations standing pulse solutions existence INSTABILITY linearized stability criterion Evans func- tions
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考虑GIS的物流配送区域划分与路径规划算法 被引量:12
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作者 潘国强 胡俊逸 洪敏 《大连海事大学学报》 CAS CSCD 北大核心 2015年第1期83-90,共8页
针对大规模VRP配送问题,提出一种配送区域划分的启发式-模拟退火混合搜索算法.针对GIS中实际路网建立路网数学模型,并在大规模VRP路径规划问题研究中与实际GIS路网相融合.对配送路径规划问题提出一种结合GIS模型约束的启发式路径搜索算... 针对大规模VRP配送问题,提出一种配送区域划分的启发式-模拟退火混合搜索算法.针对GIS中实际路网建立路网数学模型,并在大规模VRP路径规划问题研究中与实际GIS路网相融合.对配送路径规划问题提出一种结合GIS模型约束的启发式路径搜索算法.对杭州市某配送区域实际问题求解并与另一种启发式算法对比,验证了算法的有效性. 展开更多
关键词 物流配送 区域划分 路径规划 启发式算法 地理信息系统(GIS) 车辆路径问题(VRP) 模拟退火算法
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