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Combined Cellular Automaton Model for Dynamic Recrystallization Evolution of 42CrMo Cast Steel

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 80-90页

作者： Yi-Na Guo yong-tang li Wen-Yan Tian Hui-Ping Qi Hong-Hong Yan School of Electronic Information Engineering Taiyuan University of Science and Technology Shanxi Key Laboratory of Metallic Materials Forming Theory and Technology School of Materials Science and Engineering Taiyuan University of Science and Technology

The dynamic recrystallization(DRX) simulation performance largely depends on simulated grain topological struc?tures. However, currently solutions used di erent models for describing two?dimensional(2 D) and three?dimensional(3 D) grain size distributions. Therefore, it is necessary to develop a more universal simulation technique. A cellular automaton(CA) model combined with an optimized topology deformation technology is proposed to simulate the microstructural evolution of 42 CrMo cast steel during DRX. In order to obtain values of material constants adopted in the CA model, hot deformation characteristics of 42 CrMo cast steel are investigated by hot compression metal?lographic testing. The proposed CA model deviates in two important aspects from the regular CA model. First, an optimized grain topology deformation technology is utilized for studying the hot compression e ect on the topology of grain deformation. Second, the overlapping grain topological structures are optimized by using an independent component analysis method, and the influence of various thermomechanical parameters on the nucleation process, grain growth kinetics, and mean grain sizes observed during DRX are explored. Experimental study shows that the average relative root mean square error(RRMSE) of the mean grain diameter obtained by the regular CA model is equal to 0.173, while the magnitude calculated using the proposed optimized CA model is only 0.11. This paper pro?poses a novel combined CA model for simulating the microstructural evolution of 42 CrMo cast steel, which notably uses a ICA?based grain topology deformation method to optimize the overlapping grain topological structures in simulation.

关键词： 42CrMo cast steel Dynamic recrystallization Cellular automaton Grain topology Independent component analysis

Cover a Tree by Induced Matchings

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Journal of Mathematical Research and Exposition 2010年第5期30卷 845-848页

作者： Jing yong tang li DONG Xin Yu SONG College of Mathematics and Information Science Xinyan9 Normal University Henan 464000 P. R. China

The induced matching cover number of a graph G without isolated vertices, denoted by imc（G）, is the minimum integer k such that G has k induced matchings M1, M2,..., Mk such that, M1∪M2∪…∪Mk covers V（G）. This paper shows if G is a nontrivial tree, then imc（G） E {△0^＊CG）, △0^＊（G）＋ 1, △0^＊（G）＋ 2}, where △0^＊（G） = max{d0（u）＋ d0（v）： u,v ∈ V（G）,uv ∈ E（G）}.

关键词： induced matching induced matching cover tree.

Efficacy and safety of triple-antiplatelet therapy after percutaneous coronary intervention： a meta-analysis

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Chinese Medical Journal 2013年第9期126卷 1750-1754页

作者： ZHANG yong tang Hai-qin li Jin FU Zhao-xin Department of Geriatrics First Affiliated Hospital of Anhui Medical University Hefei Anhui 230022 China

Background The combination of cilostazol, aspirin and clopidogrel （triple antiplatelet therapy, TAT） after a percutaneous coronary intervention has been used as an alternative therapy. We performed a meta-analysis to evaluate the efficacy and safety of TAT for patients after percutaneous coronary intervention （PCI）. Methods We systematically searched Pubmed, Embase and Web of Science databases to identify all randomized controlled trials （RCTs） that compared dual antiplatelet therapy （DAT） with and without cilostazol after PCI. All analyses were conducted using Review Manager 5.0. Results The final analysis consisted of 4474 patients from ten studies. The combined results suggested that there was a lower risk of cardiac death （relative risk （RR）=0.55, 95% confidence interval （Cl）： 0.31-0.98, P 〈0.05） and major adverse cardiac events （MACEs）（RR=0.63, 95% Cl： 0.54-0.74, P 〈0.05） in patients treated with TAT as compared to those with DAT follow-ups after six months to one year; no significant difference was observed in bleeding and non-fatal myocardial infarction （MI）（RR=1.14, 95% Cl： 0.80-1.64, P 〉0.055 RR=0.87, 95% Cl： 0.42-1.83, P 〉0.05）. However, the rate of adverse drug reaction was higher in patients receiving TAT than in patients receiving DAT （RR=2.21, 95% Cl： 1.84-2.66, P 〈0.05）. Moreover, there was a lower risk of stent thrombosis in patients treated with TAT as compared to those treated with DAT （RR=0.44, 95% Cl： 0.21-0.94, P 〈0.05）. The TAT group had a reduced risk of target lesion revascularization （TLR）（RR=0.60, 95% Cl： 0.43-0.82, P=-0.001） and target vessel revascularization （TVR） than the DAT group （RR=0.56, 95% Cl： 0.45-0.71, P 〈0.05）. The number of MACEs was lower for patients in the TAT group than in the DAT group with diabetes mellitus sub-analysis （RR=0.41, 95% Cl： 0.28-0.61, P 〈0.05）. But no significant difference was observed between the two groups regarding MACEs in patients with drug-eluting stent implantations （RR=0.82, 95% Cl： 0.65-1.03, P

关键词： triple antiplatelet therapy dual antiplatelet therapy percutaneous coronary intervention meta-analysis

基于DCT系数空间分布的JPEG图像检索算法

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北京邮电大学学报 2009年第5期32卷 32-35页

作者：赵珊汤永利刘静河南理工大学计算机科学与技术学院河南焦作454003

为解决联合图像专家组(JPEG)图像检索时存在的问题,提出了一种检索算法.利用每个子图像块中离散余弦变换(DCT)系数的分布,构造具有旋转不变性的交流(AC)系数分布熵表征图像的内容;考虑到AC系数在DCT块中空间位置的不同而体现信息不同的... 详细信息

为解决联合图像专家组(JPEG)图像检索时存在的问题,提出了一种检索算法.利用每个子图像块中离散余弦变换(DCT)系数的分布,构造具有旋转不变性的交流(AC)系数分布熵表征图像的内容;考虑到AC系数在DCT块中空间位置的不同而体现信息不同的特点,为AC系数分布熵设置了权值,避免了由于AC系数分布熵相同而系数空间分布不同造成的误检和漏检情况.该算法不仅体现了DCT块中各个系数的统计分布,同时也捕捉到它们的空间分布信息,对图像的平移、旋转和尺度变换有一定的鲁棒性.实验结果表明,该算法具有较好的检索效果.

关键词：基于内容的图像检索离散余弦变换交流系数分布熵

基于SWRL的制造系统知识表达与按需服务过程推理框架

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计算机集成制造系统 2013年第1期19卷 187-198页

作者：李从东谢天汤勇力暨南大学管理学院广东广州510632

为实现协同制造环境下制造系统服务过程的智能性,提出"需求—资源—服务—过程"为主线的按需制造范式,结合本体、语义推理等技术,提出制造系统基于语义网规则语言的服务过程按需推理框架;建立制造需求、资源、服务、过程的本体概念和关... 详细信息

为实现协同制造环境下制造系统服务过程的智能性,提出"需求—资源—服务—过程"为主线的按需制造范式,结合本体、语义推理等技术,提出制造系统基于语义网规则语言的服务过程按需推理框架;建立制造需求、资源、服务、过程的本体概念和关系模型,构建该框架的本体知识库;基于服务按需组合生成动态服务过程思想,运用IOPE模型描述语义Web服务功能语义和动态前后件服务交互特征,提取服务过程触发推理的描述逻辑规则,并通过规则到本体知识属性的映射构建语义规则;运用Protégé和Jess推理引擎实现推理的应用模型,通过推理实验证明了该方法的有效性。

关键词：语义网规则语言服务过程语义推理描述逻辑

Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis

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Neural Regeneration Research 2025年第2期20卷 354-365页

作者： li Xu Huiming Xu Changyong tang Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor *** date,no effective treatment exists as the exact causative mechanism remains ***,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic *** most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets *** experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum *** this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model *** addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials.

关键词： aquaporin-4 experimental model neuromyelitis optica spectrum disorder pathogenesis

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压缩感知安全理论研究

北京邮电大学学报 2020年第3期43卷 125-130页

作者：汤永利赵明洁李丽香河南理工大学计算机科学与技术学院焦作454003 北京邮电大学灾备技术国家工程实验室北京100876

互联网的发展导致各种信息传输量的激增,对于大数据的处理,奈奎斯特采样定律已经不能满足许多实际工程应用的需要,而压缩感知的出现解决了这个问题.压缩感知理论指出稀疏信号可以用远小于奈奎斯特采样定律的采样数进行采样,并将原始数... 详细信息

互联网的发展导致各种信息传输量的激增,对于大数据的处理,奈奎斯特采样定律已经不能满足许多实际工程应用的需要,而压缩感知的出现解决了这个问题.压缩感知理论指出稀疏信号可以用远小于奈奎斯特采样定律的采样数进行采样,并将原始数据恢复出来.压缩感知不仅可以将数据进行压缩,而且还具有加密功能,被广泛应用到信息和网络的安全理论中.为了实现更好的加密效果,对压缩感知与其他多种技术相结合(如混沌系统、置乱和扩散等)的安全方案进行汇总,并对现有的多种方案的对比结果进行了对比分析.结果表明,现有的这些压缩感知安全方案都可以达到良好的加密效果,可以抵抗暴力攻击、统计攻击、已知明文攻击等多种攻击,具有良好的安全性.

关键词：压缩感知混沌系统置乱和扩散加密方案

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支持策略动态更新的多机构属性基加密方案

通信学报 2017年第10期38卷 94-101页

作者：闫玺玺刘媛李子臣汤永利河南理工大学计算机科学与技术学院河南焦作454003 北京印刷学院信息工程学院北京102600

属性基加密方案被认为是云存储环境下数据资源访问控制的最佳选择,但是策略更新很大程度上限制了其在实际中的应用。针对此问题,提出一种支持策略动态更新的多机构属性基加密方案。该方案引入匿名密钥分发协议为用户生成私钥,有效地保... 详细信息

属性基加密方案被认为是云存储环境下数据资源访问控制的最佳选择,但是策略更新很大程度上限制了其在实际中的应用。针对此问题,提出一种支持策略动态更新的多机构属性基加密方案。该方案引入匿名密钥分发协议为用户生成私钥,有效地保护用户的隐私,并抵抗属性机构的共谋攻击。另外,方案采用动态策略更新算法,支持任何类型的策略更新,大大减少传统策略更新中的计算和通信开销。经安全性分析证明,方案在标准模型下满足自适应选择明文攻击安全。通过对比,用户私钥和密文长度都有所减少,密文更新交给云服务器完成,降低了数据拥有者的工作量,更加贴近实际应用。

关键词：属性基加密多机构动态策略更新隐私保护

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虚拟企业细胞式治理体系

计算机集成制造系统 2007年第8期13卷 1572-1578,1638页

作者：汤勇力胡欣悦李从东暨南大学管理学院广东广州510632

为实现虚拟企业的协同运作与资源优化配置,保障总体任务的完成,建立了细胞式治理体系结构,通过重构进化适应环境的复杂性和动态性。在该体系中,核心企业组成的细胞核系统是控制中心,成员企业构成的细胞质系统提供了不可或缺的功能单元,... 详细信息

为实现虚拟企业的协同运作与资源优化配置,保障总体任务的完成,建立了细胞式治理体系结构,通过重构进化适应环境的复杂性和动态性。在该体系中,核心企业组成的细胞核系统是控制中心,成员企业构成的细胞质系统提供了不可或缺的功能单元,信息技术治理构成生物膜系统为虚拟企业治理活动提供了必需的信息技术支持。核心企业和成员企业根据各自所承担总体任务过程中的子任务价值系数,采用耦合程度不同的多元化治理结构安排。非正式社会机制是虚拟企业正式治理机制的有力补充。虚拟企业细胞式治理体系结构是一个虚拟企业治理的集成化通用理论分析和结构设计框架,可以为虚拟企业的结盟和治理提供理论指导。

关键词：虚拟企业细胞式治理体系进化子任务价值系数