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Numerical simulation of effects of cusp magnetic field on oxygen concentration of 300 mm CZ-Si

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Rare Metals 2012年第5期31卷 494-499页

作者： WANG Yongtao XU Wenting DAI Xiaolin XIAO Qinghua deng shujun YAN Zhirui ZHOU Qigang Semiconductor Materials Co. Ltd General Reseach Institute of Nonferrous Metals Beijing 100088 China General Research Institute for Non Ferrous Metals Beijing 100088 China

In magnetic Czochralski (MCZ) silicon growth, the distance and diameter of the electrified coils may affect the magnetic field intensity and melt flow. By changing the above parameters, the optimum geometric configuration of the coils was attempted. Through analyses of the oxygen concentration distribution of the crystal/melt interface, axial and radial velocity distribution of melt and the magnetic field intensity in the melt, it is found that smaller diameter of coils contributes to reducing the needed current intensity and production costs. For a given current intensity, there is a best distance of coils when the oxygen concentration at crystal/melt interface reaches the lowest. © The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2012.

关键词： Computer simulation Magnetic fields Silicon

A comparative study of hydrothermal aging effect on cerium and lanthanum doped Cu/SSZ-13 catalysts for NH_(3)-SCR

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Journal of Rare Earths 2021年第8期39卷 969-978页

作者： Di deng shujun deng Dandan He Zhiheng Wang Zhipeng Chen Yi Ji Guoping Yan Guangjin Hou Licheng Liu Hong He Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China School of Material Science and Engineering Wuhan Institute of TechnologyWuhan 430205China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Dalian National Laboratory for Clean Energy Dalian 116023China

Ce-or La-doped Cu/SSZ-13 catalysts were prepared by a hydrothermal method and Cu,Ce or La ions were incorporated through stepwise ion exchange,The catalyst activity was measured for the ammonia selective catalytic reduction *** structure and composition of catalyst were characterized by using X-ray diffraction,scanning electron microscopy,inductively coupled plasma mass spectrometry solid-state NMR,NH_(3)-TPD techniques,and the active components were examined by XPS and *** results indicate that the Ce and La doping can both completely preserve the SCR activity of Cu/SSZ-13 above 300℃,but there is also a decrease of activity below 200℃.On the other hand,Ce doping is beneficial to the formation of framework aluminum,stabilizes molecular sieve framework and Cu active sites of Cu/SSZ-13,thereby improves the catalyst hydrothermal *** La doping will decrease the amount of framework aluminum and Cu active sites of Cu/SSZ-13 after hydrothermally aging,even destroy zeolite CHA *** is quite harmful to the catalyst hydrothermal stability.

关键词： Zeolite Ammonia selective catalytic reduction Cerium Lanthanum Framework aluminum Rare earths

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一种适合于地图出版符号的反走样算法研究

武汉大学学报（信息科学版） 2005年第12期30卷 1120-1123页

作者：邓术军郭建星信息工程大学测绘学院郑州市陇海中路66号450052

在分析现有反走样算法的基础上,提出了一种适合于地图出版符号的反走样算法———“刷子法”,并通过实验对该方法的反走样效果和效率进行了全面评估。

关键词：走样反走样地图出版符号刷子法分辨率

利用SMT约束分解方法求解RTL可满足性问题

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计算机辅助设计与图形学学报 2010年第2期22卷 234-239页

作者：赵燕妮边计年邓澍军清华大学计算机科学与技术系北京100084

随着集成电路技术与工艺的不断发展,目前工业界所采用的形式验证工具已很难适应集成电路规模的飞速增长.为了对RTL电路的可满足性问题进行形式验证,提出基于超图划分的约束分解实现可满足性模理论(SMT)求解的分级验证方法.通过分析RTL... 详细信息

随着集成电路技术与工艺的不断发展,目前工业界所采用的形式验证工具已很难适应集成电路规模的飞速增长.为了对RTL电路的可满足性问题进行形式验证,提出基于超图划分的约束分解实现可满足性模理论(SMT)求解的分级验证方法.通过分析RTL电路的结构约束,对约束集合中的元素和相关变量进行约束建模,并构建带有合适权重的超图模型;利用超图划分的机制寻找带有最小割集的等量划分,实现约束分解,完成RTL电路的定界模型检验.实验结果表明,该方法能够减小处理问题的规模和求解过程中的搜索空间,提高验证效率.

关键词：形式验证约束分解寄存器传输级可满足性模理论

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RTL验证中的混合可满足性求解

计算机辅助设计与图形学学报 2007年第3期19卷 273-278,285页

作者：邓澍军吴为民边计年清华大学计算机科学与技术系北京100084

RTL混合可满足性求解方法分为基于可满足性模理论(SMT)和基于电路结构搜索两大类.前者主要使用逻辑推理的方法,目前已在处理器验证中得到了广泛的应用,主要得益于SMT支持用于描述验证条件的基础理论;后者能够充分地利用电路中的约束信息... 详细信息

RTL混合可满足性求解方法分为基于可满足性模理论(SMT)和基于电路结构搜索两大类.前者主要使用逻辑推理的方法,目前已在处理器验证中得到了广泛的应用,主要得益于SMT支持用于描述验证条件的基础理论;后者能够充分地利用电路中的约束信息,因而求解效率较高.介绍了每一大类中的典型研究及其所采用的重要策略,以及RTL可满足性求解方面的研究进展.

关键词：形式验证寄存器传输级可满足性可满足性模理论

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地图色彩管理与设计系统(英文)

仪器仪表学报 2004年第Z2期25卷 198-202页

作者：刘真邓术军蔡圣燕南京林业大学南京210042 郑州信息工程大学测绘学院郑州450052 天津科技大学包装印刷工程学院天津300222

色彩设计和色彩复制是彩色地图生产出版的关键环节。色彩管理技术在彩色地图生产出版中应用后,不仅提高了印刷地图的质量,而且几乎杜绝了因色彩复制达不到要求而造成的返工。从基于色彩复制的角度,在分析彩色地图生产中色彩设计和应用... 详细信息

色彩设计和色彩复制是彩色地图生产出版的关键环节。色彩管理技术在彩色地图生产出版中应用后,不仅提高了印刷地图的质量,而且几乎杜绝了因色彩复制达不到要求而造成的返工。从基于色彩复制的角度,在分析彩色地图生产中色彩设计和应用规律的基础上,论述了地图色彩复制的基本原理和彩色地图生产中的色彩控制技术,以及用于彩色地图生产的色彩管理与设计系统的设计原理和基本功能。

关键词：色彩管理地图生产地图色彩设计色标色谱

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin Liu Run Hou Chenghao Wu Ruishan Xie shujun Chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing Research Institute of Beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng TAO shujun HAN Huici WU Kai YANG Zhu HAN National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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剖分网格下顾及用户兴趣的矢量地图多尺度表达方法

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测绘学报 2016年第B12期45卷 127-134页

作者：俞童邓术军钱海忠杨清丽信息工程大学地理空间信息学院 61243部队

在海量空间数据的组织与表达方面,与传统的空间数据模型与方法相比,地球剖分网格表现出了极大的优势。鉴此,本文提出了一种剖分网格下顾及用户兴趣的矢量地图多尺度表达方法,首先利用大量POI数据构建空间兴趣场模型,描述用户对地理信息... 详细信息

在海量空间数据的组织与表达方面,与传统的空间数据模型与方法相比,地球剖分网格表现出了极大的优势。鉴此,本文提出了一种剖分网格下顾及用户兴趣的矢量地图多尺度表达方法,首先利用大量POI数据构建空间兴趣场模型,描述用户对地理信息的兴趣的空间分布;然后对空间要素进行分类分级,确定其表达的尺度范围;运用GeoSOT剖分理论划分不同层次的剖分面片,建立剖分面片与尺度的对应关系,根据用户对剖分面片所在区域的兴趣度大小,表达不同详细程度的空间要素,实现基于用户兴趣的空间数据多尺度表达。实验表明,该方法能够满足用户由概略到详细、由重要到次要的空间认知需求,同时能够获得较好的多尺度表达效果。

关键词：空间兴趣场地球剖分网格 GeoSOT 多尺度表达用户兴趣