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基于运动空间视觉感知的导向标志布局评价 被引量:7
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作者 吴娇蓉 胡山川 陈振武 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第8期1167-1172,1176,共7页
采用适用于建筑物内部的凸多边形分割方法对轨道站空间进行分割,提取平均深度值和便捷度2个变量分析行人流线所经过空间的结构系统;根据寻路过程中人的水平和垂直视角构建的立体空间可见视域范围结合寻路流线和流量关系分析运动过程中... 采用适用于建筑物内部的凸多边形分割方法对轨道站空间进行分割,提取平均深度值和便捷度2个变量分析行人流线所经过空间的结构系统;根据寻路过程中人的水平和垂直视角构建的立体空间可见视域范围结合寻路流线和流量关系分析运动过程中人的空间感知,建立流线可见度指标,提出轨道站内导向标志布局合理性量化评价分析方法,并结合实例进行应用分析. 展开更多
关键词 轨道站导向标志 空间便捷度 最佳空间视域 可见空间视域 流线 导向标志布局合理性指数
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基于FFT的阵列方向图快速计算 被引量:12
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作者 李建新 徐慧 +1 位作者 胡明春 邵江达 《微波学报》 CSCD 北大核心 2007年第1期10-15,共6页
分析了等距线阵方向图与傅立叶变换的一致性,用FFT算法进行阵列方向图快速计算。通过严格的数学推导,揭示变换序列与可见空间的关系,讨论了不同单元间距情况下的处理方法。文中结合实例,阐述了FFT算法在阵列方向图计算中的应用技巧,如... 分析了等距线阵方向图与傅立叶变换的一致性,用FFT算法进行阵列方向图快速计算。通过严格的数学推导,揭示变换序列与可见空间的关系,讨论了不同单元间距情况下的处理方法。文中结合实例,阐述了FFT算法在阵列方向图计算中的应用技巧,如扫描处理方法、指向分辨精度和边缘数据点估计,并指出用FFT算法计算阵列方向图其运算速度可提高一个数量级以上。 展开更多
关键词 快速傅立叶变换 线阵 阵列方向图 可见空间
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基于FFT平面相控阵天线方向图快速计算 被引量:11
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作者 李建新 陈瑞 《微波学报》 CSCD 北大核心 2009年第6期12-17,共6页
研究了二维矩形栅格平面相控阵天线方向图快速FFT计算方法,通过严格数学推导过程,揭示了平面阵列方向图与二维FFT之间内在必然联系。借助可见空间的概念,给出FFT应用详解。结合实例,验证处理方法正确性,并检验计算速度。最后,文中描述... 研究了二维矩形栅格平面相控阵天线方向图快速FFT计算方法,通过严格数学推导过程,揭示了平面阵列方向图与二维FFT之间内在必然联系。借助可见空间的概念,给出FFT应用详解。结合实例,验证处理方法正确性,并检验计算速度。最后,文中描述了切面方向图处理、扫描角精度分析、方向性系数计算等。 展开更多
关键词 快速傅立叶变换 平面阵列 方向图 可见空间
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POP广告在商业促销中的重要地位
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作者 刘勃 《中国商贸》 1997年第4期24-24,共1页
POP广告在商业促销中的重要地位POP全称为PointofPurchaseAdvertising又称PointofPurchaseDisplay。Display一词可理解为陈列广告,也可称为销售经营广告。百货商场、... POP广告在商业促销中的重要地位POP全称为PointofPurchaseAdvertising又称PointofPurchaseDisplay。Display一词可理解为陈列广告,也可称为销售经营广告。百货商场、超市、自选市场、连锁店、批发店及展... 展开更多
关键词 POP广告 促销 视觉效果 商业 广告主 重要地位 广告战略 光导纤维 可见空间 从众心理
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From Physical Space to Visual Image Space 被引量:1
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作者 YE Zetian LIN Hui LIU Xianlin YE Zetian, Ph.D, Chinese Academy of Surveying and Mapping, 16 Beitaiping Road, Haidian District, Beijing 100039, China. 《Geo-Spatial Information Science》 2003年第2期42-47,共6页
The theoretical framework of visual simulation in virtual reality is discussed. The new concept of visual image space is supposed. On the basis of visual image space, in visual perceptive sense, VR is considered as a ... The theoretical framework of visual simulation in virtual reality is discussed. The new concept of visual image space is supposed. On the basis of visual image space, in visual perceptive sense, VR is considered as a spatial simulation. The objective of the spatial simulation is to transform physical space to visual image space. Last, the prototype system, surveying & mapping virtual Reality (SMVR), is developed, and the space simulation above is realized. By use of SMVR, the real 3D representation, 3D visual analysis, virtual plan and designs can be implemented. 展开更多
关键词 virtual reality physical space visual image space space of earth surface space simulation
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关于柏林的公共空间 被引量:3
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作者 安德烈斯.G.汉普尔 王晓京 《建筑学报》 北大核心 2002年第2期11-14,共4页
公共空间,包括可见的和不可见的,包括建筑物和它周围的环境。在公共空间中,人类可以找到特定时代的表现形式。以柏林为例,作者考察人们在特定时期的想法及其表达方式是如何改变和影响公共空间的。上个世纪,柏林经历了破坏与重建的更替,... 公共空间,包括可见的和不可见的,包括建筑物和它周围的环境。在公共空间中,人类可以找到特定时代的表现形式。以柏林为例,作者考察人们在特定时期的想法及其表达方式是如何改变和影响公共空间的。上个世纪,柏林经历了破坏与重建的更替,建设思想与意识的转换,这种变化大概是世界上唯一的。各种城市和规划建筑模式都在柏林进行了尝试———似乎整个城市就是一个大工厂———而且这些尝试在城市空间的破坏与重建中都留下了它们的痕迹。 展开更多
关键词 公共空间 可见空间 可见空间 城市规划 城市空间
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Sensitivity Studies for Monitoring Tropospheric Ozone from Space Using the Ultraviolet,Visible,and Polarization Bands
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作者 CAI Zhao-Nan LIU Yi LIU Xiong 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第3期198-202,共5页
The authors analyzed the retrieval sensitivity of tropospheric ozone using simulated the Global Ozone Monitoring Experiment-2 (GOME-2) measurements. The retrieval sensitivity was evaluated by the degree of free- dom... The authors analyzed the retrieval sensitivity of tropospheric ozone using simulated the Global Ozone Monitoring Experiment-2 (GOME-2) measurements. The retrieval sensitivity was evaluated by the degree of free- dom for signal (DFS). The combination of the ultraviolet (UV), UV polarization (UVPOL), and visible (VIS) bands enhances DFS of tropospheric ozone and improves the vertical resolution of the retrieved ozone profile. UVPOL reduces the dependence on solar zenith angle, mainly in- creases the sensitivity in upper troposphere. Polarization increased the DFS by 20% on the eastern side of the GOME-2 orbit, with little improvement on the western side because the increase in DFS due to polarization is depend- ent on the relative azimuth angle. The inclusion of the visi- ble band reduces significantly the dependence on viewing geometry, and mainly increases the DFS in the lower tro- posphere (0-6 kin) by a factor of two. It was possible to retrieve several independent pieces of tropospheric ozone information from GOME-2 UV/UVPOL/VIS measure- ments, especially in the lower troposphere. 展开更多
关键词 tropospheric ozoneretrieval sensitivity GOME-2
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Accessibility analysis in manufacturing processes using visibility cones 被引量:6
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作者 尹周平 丁汉 熊有伦 《Science China(Technological Sciences)》 SCIE EI CAS 2002年第1期47-57,共11页
Accessibility is a kind of important design feature of products,and accessibility analysis has been acknowledged as a powerful tool for solving computational manufacturing problems arising from different manufacturing... Accessibility is a kind of important design feature of products,and accessibility analysis has been acknowledged as a powerful tool for solving computational manufacturing problems arising from different manufacturing processes.After exploring the relations among approachability,accessibility and visibility,a general method for accessibility analysis using visibility cones (VC) is proposed.With the definition of VC of a point,three kinds of visibility of a feature,namely complete visibility cone (CVC),partial visibility cone (PVC) and local visibility cone (LVC),are defined.A novel approach to computing VCs is formulated by identifying C-obstacles in the C-space,for which a general and efficient algorithm is proposed and implemented by making use of visibility culling.Lastly,we discuss briefly how to realize accessibility analysis in numerically controlled (NC) machining planning,coordinate measuring machines (CMMs) inspection planning and assembly sequence planning with the proposed methods. 展开更多
关键词 accessibility analysis visibility cones C-SPACE manufacturing processes
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Visible characteristics of space-based targets based on bidirectional reflection distribution function 被引量:3
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作者 WANG HongYuan ZHANG Wei WANG FuGang 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第4期982-989,共8页
A precise modeling method of visible characteristics of the space-based target was presented based on bidirectional reflection distribution function (BRDF). The background characteristics of the space-based target wer... A precise modeling method of visible characteristics of the space-based target was presented based on bidirectional reflection distribution function (BRDF). The background characteristics of the space-based target were represented to build models of direct solar radiation and reflected radiation of the Earth based on blackbody radiation theory. The geometry characteristics of the target were analyzed to establish a surface equation of each surface based on its body coordinate system. The material characteristics of the target surface were described by introducing a BRDF model which considers the character of surface Gauss statistics and self-shadow and is obtained by measurement and modeling in advance. The relative positions of the space-based target, the background radiation sources and the observation platform were determined based on coordinate con- version to judge contributing surface of the target to observation system. Then a mathematical model on visible characteristics of the space target for the given optical system was built by summing reflection components of all the surfaces. Simulation of visible characteristics of the space-based target in orbit was achieved according to its given geometrical dimensions, physical parameters and orbital parameters. The results show that the method is effective for analysis on visible characteristics of the space-based target when single reflection is considered and its surface is regularly described in a surface equation, which provides a way to real-time calculation of visible characteristics of the space-based target. 展开更多
关键词 space optics space-based target visible characteristics bidirectional reflection distribution function (BRDF)
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Fusion of VNIR and Thermal Infrared Remote Sensing Data Based on GA-SOFM Neural Network 被引量:1
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作者 WANG Chongchang YANG Guijun MA Zhen li XING Zhurong 《Geo-Spatial Information Science》 2009年第4期271-280,共10页
The multi-source data fusion methods are rarely involved in VNIR and thermal infrared remote sensing at present. Therefore, the potential advantages of the two kinds of data have not yet been adequately tapped, which ... The multi-source data fusion methods are rarely involved in VNIR and thermal infrared remote sensing at present. Therefore, the potential advantages of the two kinds of data have not yet been adequately tapped, which results in low calculation precision of parameters related with land surface temperature. A new fusion method is put forward where the characteristics of the high spatial resolution of VNIR (visible and near infrared) data and the high temporal resolution of thermal infrared data are fully explored in this paper. Non-linear fusion is implemented to obtain the land surface temperature in high spatial resolution and the high temporal resolution between the land surface parameters estimated from VNIR data and the thermal infrared data by means of GA-SOFM (genetic algorithms & self-organizing feature maps)-ANN (artificial neural net-work). Finally, the method is verified by ASTER satellite data. The result shows that the method is simple and convenient and can rapidly capture land surface temperature distribution of higher resolution with high precision. 展开更多
关键词 FUSION VNIR data thermal infrared land surface parameter GA-SOFM mapping ANN
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