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Visual information quantification for object recognition and retrieval

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Science China(Technological Sciences) 2021年第12期64卷 2618-2626页

作者： CHENG JiaLiang BIE Lin zhao xibin GAO Yue School of Software Tsinghua UniversityBeijing 100084China

The rapid development of computer vision has led to an increasing amount of 3 D data,such as multiple views and point clouds,which are widely used in 3 D object recognition and ***,the quality of 3 D data is the most crucial factor that directly affects the performance of 3 D ***,how to evaluate the 3 D data quality,especially the multi-view data quality,is still an open *** tackle this issue,we propose an entropy-based multi-view information quantification model(MV-Info model)to quantitatively evaluate the multi-view data *** proposed MV-Info model consists of hierarchical data module,feature generation module,and quantitative calculation ***,it considers the information entropy theory for more reasonable quantification *** our method,how much information we can observe from a group of views can be quantified,which can be used to support 3 D recognition and *** also designed a series of experiments to evaluate the effectiveness of the proposed *** experimental results demonstrate the rationality and validity of the proposed model.

关键词： information quantification multi-view data 3D object computer vision

A Hierarchical Ensemble Learning Framework for Energy-Efficient Automatic Train Driving

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Tsinghua Science and Technology 2019年第2期24卷 226-237页

作者： Guohua Xi xibin zhao Yan Liu Jin Huang Yangdong Deng CRRC Corporation Limited School of Software and Key Laboratory for Information System Security Ministry of Education (KLISS)/Beijing National Research Center for Information Science and Technology (BNRist) Tsinghua University

Railway transportation plays an important role in modern society. As China's massive railway transportation network continues to grow in total mileage and operation density, the energy consumption of trains becomes a serious concern. For any given route, the geographic characteristics are known a priori, but the parameters(e.g., loading and marshaling) of trains vary from one trip to another. An extensive analysis of the train operation data suggests that the control gear operation of trains is the most important factor that affects the energy consumption. Such an observation determines that the problem of energy-efficient train driving has to be addressed by considering both the geographic information and the trip parameters. However, the problem is difficult to solve due to its high dimension, nonlinearity, complex constraints, and time-varying characteristics. Faced with these difficulties, we propose an energy-efficient train control framework based on a hierarchical ensemble learning approach. Through hierarchical refinement, we learn prediction models of speed and gear. The learned models can be used to derive optimized driving operations under real-time requirements. This study uses random forest and bagging – REPTree as classification algorithm and regression algorithm, respectively. We conduct an extensive study on the potential of bagging, decision trees, random forest, and feature selection to design an effective hierarchical ensemble learning framework. The proposed framework was testified through simulation. The average energy consumption of the proposed method is over 7% lower than that of human drivers.

关键词： machine learning energy efficiency train driving system feature selection ensemble learning

Integrated importance measure for multi-state coherent systems of k level

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Journal of Systems Engineering and Electronics 2013年第6期24卷 1029-1037页

作者： xibin zhao Shubin Si Hongyan Dui Zhiqiang Cai Shudong Sun Key Laboratory for Information System Security of Ministry of Education School of SoftwareTsinghua University Ministry of Education Key Laboratory of Contemporary Design and Integrated Manufacturing Technology School of MechatronicsNorthwestern Polytechnical University

To verify the effectiveness of the integrated importance measure （IIM） for multi-state coherent systems of k level, the definition and physical meaning of IIM are demonstrated. Then, the improvement potential and Δ-importance measures are generalized to multi-state coherent systems based on the system performance level, and the relationships between IIM and traditional importance measures are discussed. The characteristics of IIM are demonstrated in both series and parallel systems. Also, an application to an oil transportation system is given. The comparison results show that：（i） IIM has some useful properties that are not possessed by traditional importance measures; （ii） IIM is effective in evaluating the component role in multi-state systems when the component reliability and the failure rate are simultaneously considered.

关键词： multi-state coherent system system performance level integrated importance measure system reliability

Three-dimensional conformal intensity-modulated radiation therapy of left femur foci does not damage the sciatic nerve

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Neural Regeneration Research 2014年第20期9卷 1824-1829页

作者： Wanlong Xu xibin zhao Qing Wang Jungang Sun Jiangbo Xu Wenzheng Zhou Hao Wang Shigui Yan Hong Yuan People’s Hospital of Xinjiang Uygur Autonomous Region The Second Affiliated Hospital of Zhejiang University School of Medicine

During radiotherapy to kill femoral hydatid tapeworms, the sciatic nerve surrounding the focus can be easily damaged by the treatment. Thus, it is very important to evaluate the effects of ra- diotherapy on the surrounding nervous tissue. In the present study, we used three-dimensional, conformal, intensity-modulated radiation therapy to treat bilateral femoral hydatid disease in Meriones meridiani. The focus of the hydatid disease on the left femur was subiected to radio- therapy （40 Gy） for 14 days, and the right femur received sham irradiation. Hematoxylin-eosin staining, electron microscopy, and terminal deoxynucleotidyl transferase-dUTP nick end labeling assays on the left femurs showed that the left sciatic nerve cell structure was normal, with no ob- vious apoptosis after radiation. Trypan blue staining demonstrated that the overall protoscolex structure in bone parasitized with Echinococcus granulosus disappeared in the left femur of the animals after treatment. The mortality of the protoscolex was higher in the left side than in the right side. The succinate dehydrogenase activity in the protoscolex in bone parasitized with Echi- nococcus granulosus was lower in the left femur than in the right femur. These results suggest that three-dimensional conformal intensity-modulated radiation therapy achieves good therapeutic effects on the secondary bone in hydatid disease in Meriones meridiani without damaging the morphology or function of the sciatic nerve.

关键词： nerve regeneration three-dimensional conformal intensity-modulated radiation thera-py hydatid disease sciatic nerve neurons radiation damage succinate dehydrogenase NSFC grants neural regeneration

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企业环境创新的理论及应用研究

中州学刊 2010年第2期 38-42页

作者：赵锡斌武汉大学经济与管理学院湖北武汉430072

企业环境创新是企业技术创新、制度创新、组织与管理创新的基本保证。但是,由谁来创新企业环境,或者说,企业环境创新的主体是谁?迄今还存在着理论认识偏差和实践行为偏差。一般认为,政府是营造企业环境的主体。实际上,在国内外大量的企... 详细信息

企业环境创新是企业技术创新、制度创新、组织与管理创新的基本保证。但是,由谁来创新企业环境,或者说,企业环境创新的主体是谁?迄今还存在着理论认识偏差和实践行为偏差。一般认为,政府是营造企业环境的主体。实际上,在国内外大量的企业管理实践中,有足够的证据表明,企业可以改变、控制或"操纵"组织运作的环境,并创造出有利于企业发展的新环境。企业环境创新的主体不仅是政府,在市场经济条件下,企业也是而且应当是环境创新的主体。

关键词：企业环境环境创新创新主体创新路径

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QPSK非平衡性调制技术

半导体技术 2008年第1期33卷 80-82页

作者：赵夕彬中国电子科技集团公司第十三研究所石家庄050051

正交相移键控(QPSK)调制技术已经在工程中得到了广泛应用,然而随着电子对抗技术的发展,QPSK的非平衡调制技术水平也得到了相应的提高,以专门针对通信或定位中的QPSK调制进行干扰。介绍一种实用的QPSK非平衡性调制技术及其系统构成,并对... 详细信息

正交相移键控(QPSK)调制技术已经在工程中得到了广泛应用,然而随着电子对抗技术的发展,QPSK的非平衡调制技术水平也得到了相应的提高,以专门针对通信或定位中的QPSK调制进行干扰。介绍一种实用的QPSK非平衡性调制技术及其系统构成,并对单片DDS调制芯片进行分析,对系统配置及软件开发的主要步骤分别说明。采用该技术可以有效解决干扰信号形成,并且与计算机接口兼容性好,可靠性高,具有较强的工程实用性。

关键词：正交相移键控非平衡调制干扰信号

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固态脉冲功率放大器脉冲波形顶降的研究

半导体技术 2009年第4期34卷 381-384,392页

作者：赵夕彬中国电子科技集团公司第十三研究所石家庄050051

针对固态脉冲功率放大器存在脉冲波形顶降问题,从功率放大器的基本原理构成出发,对引起脉冲顶降的三个主要方面进行了分析讨论:GaAs晶体管脉冲调制开关电路、Si微波脉冲功率晶体管自身顶降以及功率晶体管的匹配电路,通过理论推导指出了... 详细信息

针对固态脉冲功率放大器存在脉冲波形顶降问题,从功率放大器的基本原理构成出发,对引起脉冲顶降的三个主要方面进行了分析讨论:GaAs晶体管脉冲调制开关电路、Si微波脉冲功率晶体管自身顶降以及功率晶体管的匹配电路,通过理论推导指出了脉冲顶降产生的原因,结合设计制作固态功率放大器时常出现的脉冲顶降问题,提出了解决办法及改善途径,并通过实验进行了验证,使脉冲顶降得到了改善。

关键词：脉冲功率放大器微波脉冲晶体管调制电路脉冲波形顶降

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网格环境下的分布式RBAC模型框架

计算机工程 2006年第6期32卷 163-166页

作者：徐松赵曦滨顾明清华大学软件学院北京100084

分析了网格访问控制的特性,提出了基于PKI的分布式RBAC模型(G-RBAC),它实现了网格访问控制中的跨信任域授权,并且利用可变属性值的授权证书使得系统能够动态地根据用户的登录环境授予不同的权限。该文给出了G-RBAC的形式化描述、角色分... 详细信息

分析了网格访问控制的特性,提出了基于PKI的分布式RBAC模型(G-RBAC),它实现了网格访问控制中的跨信任域授权,并且利用可变属性值的授权证书使得系统能够动态地根据用户的登录环境授予不同的权限。该文给出了G-RBAC的形式化描述、角色分类以及访问验证算法。最后通过一个实例说明了具体的访问控制过程。

关键词： RBAC 访问控制网格 PKI 授权环境感知

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面向虚拟组织的安全目录服务

计算机工程 2005年第9期31卷 70-72,144页

作者：李晖赵曦滨顾明清华大学软件学院北京100084

针对虚拟组织中资源管理的动态性、多样性等特点及其安全方面的需求,提出了一种面向虚拟组织资源管理的安全目录服务方案。该方案不但保证了资源的快速访问,而且为目录服务提供了安全可靠的运行环境,对虚拟组织的形成和发展具有重要意义。