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Strategies for Applying LED Lights in Night Space Lighting for Bridges
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作者 Yingling Dai Qinghua Zhao 《Journal of World Architecture》 2024年第3期57-62,共6页
LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application s... LED lights have been widely used in urban night space lighting in recent years as they are small,energy-saving,and efficient.This article explores the use of LEDs in bridge night space lighting and their application strategies.The aim is to offer valuable insights and references for urban planners and bridge lighting designers in China.By advancing the application of LED technology in bridge night lighting,the goal is to enhance the city’s nighttime ambiance,making the bridge an iconic landmark and a defining feature of the city. 展开更多
关键词 Bridge night space lighting LED application Color band and gradient Artistic value Online publication:July 11 2024
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Light Space Cascaded Shadow Maps Algorithm for Real Time Rendering 被引量:2
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作者 梁晓辉 马上 +1 位作者 岑丽霞 于卓 《Journal of Computer Science & Technology》 SCIE EI CSCD 2011年第1期176-186,共11页
Owing to its generality and efficiency, Cascaded Shadow Maps (CSMs) has an important role in real-time shadow rendering in large scale and complex virtual environments. However, CSMs suffers from redundant rendering... Owing to its generality and efficiency, Cascaded Shadow Maps (CSMs) has an important role in real-time shadow rendering in large scale and complex virtual environments. However, CSMs suffers from redundant rendering problem -- objects are rendered undesirably to different shadow map textures when view direction and light direction are not perpendicular. In this paper, we present a light space cascaded shadow maps algorithm. The algorithm splits a scene into non-intersecting layers in light space, and generates one shadow map for each layer through irregular frustum clipping and scene organization, ensuring that any shadow sample point never appears in multiple shadow maps. A succinct shadow determination method is given to choose the optimal shadow map when rendering scenes. We also combine the algorithm with stable cascaded shadow maps and soft shadow algorithm to avoid shadow flicking and produce soft shadows. The results show that the algorithm effectively improves the efficiency and shadow quality of CSMs by avoiding redundant rendering, and can produce high-quality shadow rendering in large scale dynamic environments with real-time performance. 展开更多
关键词 shadow mapping light space redundant rendering large scale dynamic environments
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Structured Light 3D Vision Based on Laser Scanning Space-encoding and Its Synchro Control 被引量:1
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作者 于晓洋 强锡富 +1 位作者 张健 吴丽莹 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第2期20-24,共5页
This paper presents the principle and mathematic model for the 3D depth map method based on space encoding images performed by modulating scanning structuredlight according to time sequences,and the synchro control ... This paper presents the principle and mathematic model for the 3D depth map method based on space encoding images performed by modulating scanning structuredlight according to time sequences,and the synchro control among the camera,laser diode modulation and scanning polyhedron. 展开更多
关键词 D VISION STRUCTURED light space encoding LASER SCANNING SYNCHRO control
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Effects of Light Source in Road Green Spaces on the Growth of Picea koraiensis in Harbin
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作者 姜珊 王擎宇 +2 位作者 马迪 时春红 岳桦 《Journal of Landscape Research》 2009年第12期56-61,共6页
With Picea koraiensis as the research object which have similar growth vigor in a same habitat, the photosynthetic rate, transpiration rate, chlorophyll content, weight of dry-matter and leaf color change of Picea kor... With Picea koraiensis as the research object which have similar growth vigor in a same habitat, the photosynthetic rate, transpiration rate, chlorophyll content, weight of dry-matter and leaf color change of Picea koraiensis in different lighting conditions were determined. Environment without light sources was taken as the control group. The results showed that different light sources and different distances from light sources to plants had diversified impact on the photosynthetic physiology of Picea koraiensis. Among these different color lights, green light had the least influence on Picea koraiensis, yellow light and purple light had greater influence. 展开更多
关键词 ROAD light PICEA koraiensis ROAD green spaceS
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The Architectural Expression of Space and Form Created by the Light in the Works of Alvaro Siza 被引量:1
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作者 Chang Sung Kim Kyung Wook Seo 《Journal of Building Construction and Planning Research》 2014年第2期118-131,共14页
The light is an important element which helps people perceive objects. Therefore, it is important for architects to make the light and space be in harmony with each other. In this study, we analyzed the works of Alvar... The light is an important element which helps people perceive objects. Therefore, it is important for architects to make the light and space be in harmony with each other. In this study, we analyzed the works of Alvaro Siza with a view to understand the conceptual value of the light expressed in his works and his principles in controlling it. According to the results of the study, the Siza’s architecture is not a mere theoretical one trapped inside formality, but is a sensual and experiential one based on the locality. He was willing to use void spaces to invite the light in free-flowing plans, in order to invigorate and extend architectural spatiality to create deeper visual effect. In addition, the refined light in his works helped visitors experience the continuous forms and spaces by their own movements, while using the changes of the light to stimulate the interest of visitors and highlight the sequence of spaces. 展开更多
关键词 Alvaro Siza light FORM space
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Philosophical Approach to Space Fabric and Propagation of Light 被引量:1
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作者 Pramod Kumar Agrawal 《Natural Science》 2021年第10期457-468,共12页
First, the paper proposes that a cosmological entity such as a photon and a physical entity such as an electron belong to two different levels of the Universe. The cosmological entities do not have any physical parame... First, the paper proposes that a cosmological entity such as a photon and a physical entity such as an electron belong to two different levels of the Universe. The cosmological entities do not have any physical parameters. Thus, several mysteries of quantum physics are still unresolved because both are considered in the same paradigm. This paper further estab-lishes that the spatial space (medium of propagation) is a fabric made of different cosmo-logical substances. It explains how the space fabric plays an important role in creating dif-ferent cosmic phenomena such as gravitation, repulsion, cosmic inflation, and other mys-teries. This spatial space fabric accepts the electromagnetic wave by way of physical time, creating a spacetime continuum. Next, the paper proposes a new vision that explains how an electromagnetic wave transports photons from an emitter to a receiver with a constant velocity by outlining a new paradigm of time and space and precisely treating photons as cosmological substances. This vision explains how the second postulate of Einstein’s special theory of relativity remains valid even if the time dilation due to velocity is not a reality. The correctness of the approach is validated through the results obtained from previous well-known experiments. 展开更多
关键词 Propagation of light Time Dilation Cosmological World PHOTON space Fabric
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Space Flight, Astronautics and Light Barrier
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作者 SongJian 《工程科学(英文版)》 2005年第2期1-9,共9页
Amazing achievements and accomplishments of space science and technologies in the past half-century have profoundly affected all disciplines of natural science and engineering. By the end of 20(th) Century, man or man... Amazing achievements and accomplishments of space science and technologies in the past half-century have profoundly affected all disciplines of natural science and engineering. By the end of 20(th) Century, man or man-made spacecrafts landed, or approached and surveyed all planets of solar system and their moons except Pluto. Biologists believe that life may emerge and evolve wherever liquid water exists. No liquid water is ever found yet on all planets and their moons in Solar System except for our Earth. Our mother planet turned out to be the only life-supporting oasis within 4 light years of the Milky Way. It is suggested in this article that time has come for science and engineering communities to study and prepare interstellar flight of manned or unmanned spacecrafts beyond Solar System. Four issues are to be addressed as prerequisite for such flight, namely, detailed survey of nearby space beyond Solar System, design of nuclear fusion rocket engine, long-sustainable on-board life-supporting system and breakthrough of the light barrier. 展开更多
关键词 空间探测 航天学 光栅 星际飞行
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Optical Design and Stray Light Analysis of the Space Infrared Optical System 被引量:1
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作者 Yuchen Zhao Yanjun Xu +2 位作者 Changzheng Chen Fan Zhang Jianyue Ren 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第1期32-36,共5页
This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the... This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the system is necessary to analyze and restrain. The optical system with a focal length of 1 200 mm,an entrance pupil diameter of 600 mm,an F-number of 2,a field of view of 3°× 0. 15°,a working wave band of 8 μm-10 μm,and the image quality of the optical system almost approach to diffraction limits in all field of view.Then the mathematical models of stray light are built,and the suppressive structure is established to eliminate the effect of stray light. Finally,TraceP ro is used to analyze and simulate stray light with and without the suppressive structure,and also get the results of the PST curves. The results indicate that appropriate optical system and suppressive structure can highly reduce the stray light of the space infrared optical system. 展开更多
关键词 space infrared optical system off-axis optical system stray light Point Source Transmission(PST)
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Modified Lorentz Transformations and Space-Time Splitting According to the Inverse Relativity Model
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作者 Michael Girgis 《Journal of Applied Mathematics and Physics》 2024年第7期2467-2489,共23页
Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fab... Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fabric of space-time into a positive subspace-time that represents the space of causality and a negative subspace-time which represents a space without causality, thus, in the special case, we have new transformations for the coordinates of space and time modified from Lorentz transformations specific to each subspace, where the contraction of length disappears and the speed of light is no longer a universal constant. In the general case, we have new types of matric tensor, one for positive subspace-time and the other for negative subspace-time. We also find that the speed of the photon decreases in positive subspace-time until it reaches zero and increases in negative subspace-time until it reaches the speed of light when the photon reaches the Schwarzschild radius. 展开更多
关键词 Four-Dimensional Vector Analysis Four-Dimensional Subspace Causal space Analysis of the Speed of light Inverse Theory of Relativity
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基于空间自适应剖分的Lightcuts多光源聚类算法
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作者 袁昱纬 刘传辉 +2 位作者 全吉成 王宏伟 吴晨 《海军航空工程学院学报》 2017年第2期181-186,198,共7页
针对Lightcuts算法在面对大规模复杂光源时计算效率较低的问题,提出了一种基于空间自适应剖分的Lightcuts多光源聚类算法。该算法采用二叉树森林代替传统Lightcuts算法中的二叉树,并提出自适应的视景体划分方法对三维场景进行剖分,通过... 针对Lightcuts算法在面对大规模复杂光源时计算效率较低的问题,提出了一种基于空间自适应剖分的Lightcuts多光源聚类算法。该算法采用二叉树森林代替传统Lightcuts算法中的二叉树,并提出自适应的视景体划分方法对三维场景进行剖分,通过构建包含"簇-光源"对的列表,快速剔除与当前渲染点无关的光源,同时利用空间聚类的相似性减少"光源割"搜索过程中的重复计算。实验结果表明,与传统方法相比,文章提出的算法在"光源割"计算阶段能够将搜索步数平均减少30.71%~42.09%,绘制时间平均缩短28.35%~34.84%,有效地加快了Lightcuts算法的计算速度,提高了多光源三维场景的绘制效率。 展开更多
关键词 多光源 lightcuts 自适应空间剖分 二叉树森林 场景绘制
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断纸残篇中唤起瞬间诗意 评俞挺新作“M-Space”小美术馆 被引量:1
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作者 吴洪德 《时代建筑》 2016年第4期114-121,114,共8页
建筑师俞挺新近完成的"M-Space"小美术馆是对碎片化的外在环境和历史文脉的一次敏感的回应。对偶的设计思维促使他在美术馆、图书馆和博物馆三者之间采取不同的设计策略,并表现为纯粹、轻透的新建体量与复杂、矛盾的室内改造... 建筑师俞挺新近完成的"M-Space"小美术馆是对碎片化的外在环境和历史文脉的一次敏感的回应。对偶的设计思维促使他在美术馆、图书馆和博物馆三者之间采取不同的设计策略,并表现为纯粹、轻透的新建体量与复杂、矛盾的室内改造之间的对比。半透明表皮体现了江南意味的光影关系。建筑师对非形似熟悉感的追求使其将营造氛围放到了设计的首位。 展开更多
关键词 “M—space”小美术馆 俞挺 对偶 光影 非形似的熟悉感
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Light-induced acoustic effect in LiNbO3:Fe:Ce crystals
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作者 黄伟 吴仲康 王长青 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第11期2231-2234,共4页
The phenomena of acoustic emission in LiNbO3:Fe:Ce crystals have been observed in the process of light-induced quasi-breakdown. It is found that the ultra-high frequency acoustic signal introduced into the crystal i... The phenomena of acoustic emission in LiNbO3:Fe:Ce crystals have been observed in the process of light-induced quasi-breakdown. It is found that the ultra-high frequency acoustic signal introduced into the crystal is modulated by the low frequency acoustic waves. Its frequency increases with the increase of the intensity of incident light and its jump period of breakdown is the same as that of the photovoltaic current Ic, the change of light-induced refractive index △n and the diffracted light intensity L. This phenomenon has been analysed in this paper, which is caused by the inverse piezoelectric strain effect of the jump of space charge field during the quasi-breakdown. 展开更多
关键词 photovoltaic current photo-refractive space charge field light induced quasi-breakdown
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基于SSK的室内VLPC系统设计及性能分析
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作者 王法松 姜雯 +1 位作者 李睿 史士杰 《电子学报》 EI CAS CSCD 北大核心 2024年第6期1809-1816,共8页
本文设计了一个多输入单输出(Multiple-Input Single-Output,MISO)的三维室内可见光定位通信一体化(Visible Light Position and Communication,VLPC)系统,该系统在接收端基于接收信号强度(Received Signal Strength,RSS)的三维可见光定... 本文设计了一个多输入单输出(Multiple-Input Single-Output,MISO)的三维室内可见光定位通信一体化(Visible Light Position and Communication,VLPC)系统,该系统在接收端基于接收信号强度(Received Signal Strength,RSS)的三维可见光定位(Visible Light Position,VLP)算法获得定位数据,同时估计信道状态信息(Channel State Information,CSI)并上传给发射端进行定向通信.该系统的发射端基于空移键控(Space Shift Keying,SSK)的室内可见光通信(Visible Light Communication,VLC)技术实现系统的通信功能.另外,本方案可以完全避免通信与定位子系统之间的干扰.同时,通过推导定位误差的克拉美罗下界(Cramér-Rao Lower Bound,CRLB)和SSK-VLC的通信可达速率来评估本文提出的VLPC系统的性能.仿真结果验证了本文所提方案的有效性. 展开更多
关键词 可见光定位 可见光通信 空移键控 克拉美罗下界 可达速率
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Dark Matter: The Source of Space and Time
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作者 Keith G. Lyon 《Journal of Modern Physics》 2016年第9期920-927,共8页
A simple assumption for dark matter leads to magnetic-monopole-like terms to Maxwell’s Equations, a photon model with wave-particle duality, nuclear stability, a decelerating expansion of the universe, and a dark-mat... A simple assumption for dark matter leads to magnetic-monopole-like terms to Maxwell’s Equations, a photon model with wave-particle duality, nuclear stability, a decelerating expansion of the universe, and a dark-matter relativity that defines the origin of space and time. 展开更多
关键词 Dark Matter PHOTON Speed of light Nuclear Stability space Time SUPERCONDUCTIVITY Nuclear Fusion Magnetic Monopole
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Faster than the Speed of Light Is a Quantum Phenomena
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期379-382,共4页
Classical Mechanics using Einstein’s theories of relativity places a limit on speed as the speed of light. Quantum Mechanics has no such limitation. To understand space accelerating faster than the speed of light and... Classical Mechanics using Einstein’s theories of relativity places a limit on speed as the speed of light. Quantum Mechanics has no such limitation. To understand space accelerating faster than the speed of light and information being exchanged instantaneously between two entangled electrons separated by huge distances, one uses Planck’s length, Planck’s time, and Planck’s mass to indicate that space and time are discrete and therefore along with masses smaller than Planck’s mass are Quantum Mechanical in nature. Faster than the speed of light c = 3 × 10<sup>8</sup> m/s is a classical effect only in dimensions of space lower than our 3-D Universe, but it is a Quantum effect in all dimensions of space. Because space can oscillate sending out ripples from the source, it is the medium used for transporting light waves and gravity waves. 展开更多
关键词 Faster than the Speed of light CLASSICAL QUANTUM Planck’s Units space as a Medium Comparison with String Theory
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基于HSV空间的煤矿井下低光照图像增强方法 被引量:2
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作者 张亚邦 李佳悦 王满利 《红外技术》 CSCD 北大核心 2024年第1期74-83,共10页
针对煤矿井下采集到的图像对比度低、光照不均和细节信息弱等问题,提出一种基于色相-饱和度-明度(Hue-Saturation-Value,HSV)颜色空间的煤矿井下低光照图像增强方法。该方法基于图像的HSV空间,通过对低光照图像的亮度通道V通道的主要结... 针对煤矿井下采集到的图像对比度低、光照不均和细节信息弱等问题,提出一种基于色相-饱和度-明度(Hue-Saturation-Value,HSV)颜色空间的煤矿井下低光照图像增强方法。该方法基于图像的HSV空间,通过对低光照图像的亮度通道V通道的主要结构和边缘细节分别进行对比度增强,这样可以更好地抑制图像细节丢失,同时可以较好地再现原图中的轮廓和纹理细节。首先,将输入的煤矿井下低光照图像转换到HSV空间,利用相对全变分滤波(RTV)与改进的边窗滤波(SWF),分别对提取的V通道图像进行主要结构提取和轮廓边缘保留,对其非线性灰度拉伸后利用主成分分析融合技术(PCA)重构V通道图像,即融合V通道图像的主要结构和精细结构,最后合成图像,完成图像增强。通过实验验证,提出的基于HSV空间的煤矿井下低光照图像增强方法,在色彩和边缘模糊处理等方面表现良好,在煤矿井下工作面等环境中,对图像进行定量和定性实验,结果表明,与6种方法相比,增强图像的对比度、自然度和图像细节方面表现更好。 展开更多
关键词 图像增强 HSV空间 煤矿井 低光照图像 相对全变分滤波 边窗滤波
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株行距配置对冬小麦冠层结构、光环境及产量的影响
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作者 张颖 王超 骆永丽 《山东农业科学》 北大核心 2024年第8期37-43,共7页
为明确株行距配置对冬小麦冠层光环境及产量的影响,本试验在大田条件下,以山农28作为供试品种,研究两个密度即150万hm^(-2)(D1)和225万hm^(-2)(D2)和3个行距即10 cm(R1)、15 cm(R2)、20 cm(R3)组配的6个株行距配置处理对小麦叶面积指数... 为明确株行距配置对冬小麦冠层光环境及产量的影响,本试验在大田条件下,以山农28作为供试品种,研究两个密度即150万hm^(-2)(D1)和225万hm^(-2)(D2)和3个行距即10 cm(R1)、15 cm(R2)、20 cm(R3)组配的6个株行距配置处理对小麦叶面积指数、叶倾角、叶片叶绿素含量、冠层光合有效辐射、群体光合速率、产量及其构成因素的影响,旨在优化冬小麦株行距配置,提高单产。结果表明,D1密度下小麦生育前期容易形成良好的冠层光环境,有助于营养物质积累,为高产打下基础;相同行距下开花期小麦群体的光合速率表现为D1>D2,说明D1密度有助于叶片中营养物质积累和向籽粒转移;D2密度下小麦生育后期的冠层光环境优于D1,有助于叶片营养物质的持续供应;R1行距下冠层光环境明显优于R2和R3,能够吸收更多的光能,光合作用能力更强。密度和行距二者互作对小麦产量及其构成因素的作用表现为:D1R1>D1R2>D1R3>D2R1>D2R2>D3R3。综上,调整株行距配置是提高冬小麦产量潜力的重要途径,D1R1株行距配置更有助于形成良好的冠层光环境,能够获得最高产量,为最佳株行距配置方式。 展开更多
关键词 冬小麦 种植密度 行距 冠层光环境 产量
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简谈航站楼消防应急照明设计
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作者 魏志刚 田晓艳 《建筑电气》 2024年第3期64-68,4,共6页
随着航空行业的迅速发展,航站楼作为航空客运的重要场所,体积越来越庞大、疏散路径越来越复杂、装修装饰要求越来越高,对消防应急照明设计的要求也越来越高。本文结合某航站楼高大空间多的特点,探讨应急照明设计的重要性,并针对项目中... 随着航空行业的迅速发展,航站楼作为航空客运的重要场所,体积越来越庞大、疏散路径越来越复杂、装修装饰要求越来越高,对消防应急照明设计的要求也越来越高。本文结合某航站楼高大空间多的特点,探讨应急照明设计的重要性,并针对项目中的实际问题提出一些应对措施及解决方案。 展开更多
关键词 航站楼 高大空间 低位应急照明 消防应急灯具 DIALUX 照度 控光 灵敏度校验
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组合光透视下小面积室内封闭空间分割方法
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作者 赵会宾 张立 《激光杂志》 CAS 北大核心 2024年第5期231-235,共5页
为提高室内空间的优化规划设计能力,提出基于点云数据语义分割的组合光透视下小面积室内封闭空间分割方法。构建小面积室内封闭空间的环境三维信息感知模型,采用室内空间点云提取室内封闭空间图像的坐标信息,结合语义组合特征分割方法... 为提高室内空间的优化规划设计能力,提出基于点云数据语义分割的组合光透视下小面积室内封闭空间分割方法。构建小面积室内封闭空间的环境三维信息感知模型,采用室内空间点云提取室内封闭空间图像的坐标信息,结合语义组合特征分割方法将融合空间信息映射到高分辨空间异质单元结构中,引入几何约束的子空间投影特征信息,结合组合光透视的高分辨率分割图模型参数融合方法,提取小面积室内封闭的端元,采用点云数据语义分割方法实现空间分割。结果表明,采用该方法有效实现对复杂室内场景的三维重建,空间分割的均方根误差较低为0.808%,峰值信噪比较高42.156 dB,空间分割速度较快,平均为12.83 ms。 展开更多
关键词 组合光透视 小面积 室内封闭空间 分割 语义组合特征分割
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A New Perspective on Advanced Space Travel
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作者 Peter Bissonnet 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第1期14-24,共11页
This paper attempts to delve into the mystery of space travel. Consequently, it will be necessary to re-examine concepts which scientists hold dear. In addition, it is the author’s contention that the so-called weak ... This paper attempts to delve into the mystery of space travel. Consequently, it will be necessary to re-examine concepts which scientists hold dear. In addition, it is the author’s contention that the so-called weak force is the seat of a powerful new energy source which can be used to propel spacecraft to be unheard of velocities utilizing a variable scalar gravitational “constant”. One of the major obstacles faced is that normally the so-called “arc length” ds will be equal to zero at the speed of light (because of its dependence upon relative velocity), and since ds is used in the denominator of equations of motion, such equations will become meaningless. This paper will continue to use the arc length ds, along with its implied proper time;however, this paper will use a different method of approach to this problem which will involve divorcing ds from its dependence upon relative velocity as a result of the aforementioned generalization. The approach will be to use a complex mass-velocity vector (not momentum vector) over the usual four dimensional space-time manifold domain. The mass-velocity vector is introduced, because it is assumed that a gradient in φ or φ/μ (to be controlled from within the spacecraft) will cause not only a change in the velocity of the spacecraft, but also a change in the apparent inertial/gravitational mass mo of the spacecraft in a coordinated way. This is the guiding principle of this paper! 展开更多
关键词 Variable GRAVITATIONAL “Constant” space TRAVEL GREATER THAN the Speed of light WEAK Force
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