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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3d Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL normalization Harmonic Oscillator
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GIS Applications for Building 3D Campus, Utilities and Implementation Mapping Aspects for University Planning Purposes
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作者 Abdulla AI-Rawabdeh Nadhir A1-Ansari +1 位作者 Hussain Attya Sven Knutsson 《Journal of Civil Engineering and Architecture》 2014年第1期19-28,共10页
In city planning managing, the third dimension is becoming a necessity. Using 3D GIS modeling offers a flexible interactive system while providing one of the best visual interpretation of data which supports planning ... In city planning managing, the third dimension is becoming a necessity. Using 3D GIS modeling offers a flexible interactive system while providing one of the best visual interpretation of data which supports planning and decision processes for city planners. As a result, 3D GIS model expresses terrain features in an intuitive way which enhances the management and analysis of a proposed project through 3D visualization. This paper discusses the concept of 3D GIS modeling techniques using a simple procedure to generate a university campus model (real 3D GIS model) which will show the effectiveness of this approach. The 3D GIS model provides access to mapping data to support planning, design and data management. Intelligent GIS models and GIS tools help community planning and apply regional and discipline-specific standards. Integration of GIS spatial data with campus organization helps to improve quality, productivity and asset management. The following study built 3D GIS map and all utility information for AI al-Bayt University campus as an example. The primary objective is to improve data management (e.g., maps, plans, usage of facilities and services) and to develop methods using 3D spatial analysis for specific applications at the university. 展开更多
关键词 3d GIS model ArcScene DATABASE AI al-Bayt university Jordan.
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Multi-level spherical moments based 3D model retrieval
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作者 LIU Wei HE Yuan-jun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第9期1500-1507,共8页
In this paper a novel 3D model retrieval method that employs multi-level spherical moment analysis and relies on voxelization and spherical mapping of the 3D models is proposed. For a given polygon-soup 3D model, firs... In this paper a novel 3D model retrieval method that employs multi-level spherical moment analysis and relies on voxelization and spherical mapping of the 3D models is proposed. For a given polygon-soup 3D model, first a pose normalization step is done to align the model into a canonical coordinate frame so as to define the shape representation with respect to this orientation. Afterward we rasterize its exterior surface into cubical voxel grids, then a series of homocentric spheres with their center superposing the center of the voxel grids cut the voxel grids into several spherical images. Finally moments belonging to each sphere are computed and the moments of all spheres constitute the descriptor of the model. Experiments showed that Euclidean distance based on this kind of feature vector can distinguish different 3D models well and that the 3D model retrieval system based on this arithmetic yields satisfactory performance. 展开更多
关键词 3d model retrieval Spherical moments Feature extraction Pose normalization
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专业认证背景下师范生“三习互嵌式”教育实践模式探析 被引量:2
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作者 李广海 李淑雯 《沈阳师范大学学报(教育科学版)》 2023年第4期98-104,共7页
教育实践是师范生提升教学技能、深化教学理论的重要途径,教育见习、教育研习和教育实习是教育实践的主要形式。师范专业认证标准对“三习”的内容、课时均予以详细规定,但对如何实施“三习”尚未作出明确指导,主要由各级各类各师范院... 教育实践是师范生提升教学技能、深化教学理论的重要途径,教育见习、教育研习和教育实习是教育实践的主要形式。师范专业认证标准对“三习”的内容、课时均予以详细规定,但对如何实施“三习”尚未作出明确指导,主要由各级各类各师范院校根据自己的实际情况进行安排。由此,部分师范院校在教育实践中出现“三习”割裂的问题。基于此,构建“三习互嵌式”教育实践模式,并将这一模式付诸实施,有助于进一步总结教育见习、教育研习和教育实习相结合的经验与不足,从而为提升师范院校的实践教学质量与人才培养水平提供助益。 展开更多
关键词 专业认证 师范生 “三习互嵌式” 教育实践模式
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一种新型结构性土三维本构模型 被引量:2
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作者 邢国起 肖洪天 李大勇 《水利水电技术》 CSCD 北大核心 2017年第6期54-59,140,共7页
在NAKAI等基于应力张量t_(ij)和修正剑桥模型建立的能够描述中主应力影响且适用于描述正常固结土强度和变形规律的三维本构模型的基础上,通过引入能够描述土体密实度的状态变量ρ和土体黏结效应的状态变量ω,提出了适用于描述结构性土... 在NAKAI等基于应力张量t_(ij)和修正剑桥模型建立的能够描述中主应力影响且适用于描述正常固结土强度和变形规律的三维本构模型的基础上,通过引入能够描述土体密实度的状态变量ρ和土体黏结效应的状态变量ω,提出了适用于描述结构性土强度和变形规律的新型结构性三维本构模型。这一模型具有以下特点:结构性土三维本构模型在正常固结土的三维本构模型的基础上仅增加一个材料参数的情况下能够较好地描述三维应力状态下试样排水与不排水剪切特性、固结特性、围压对应力路径和应力应变曲线的影响及平均应力、偏应力增大时出现的应力路径可逆性等特点。应用新型结构性土三维本构模型对粉质黏土的固结试验和三轴剪切试验进行模拟计算,验证了其在模拟结构性土特征方面的可行性。 展开更多
关键词 应力张量tij 修正剑桥模型 正常固结土 结构性土 三维本构模型
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新型钢次级弧形直线感应电动机法向力研究 被引量:1
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作者 汪旭东 张志华 许孝卓 《微特电机》 北大核心 2010年第5期1-3,共3页
提出一种新型钢次级弧形直线感应电动机,采用多层行波电磁场理论建立该电机的区域模型,推导出法向力计算公式,建立该钢次级弧形直线感应电动机三维瞬态有限元仿真模型,仿真结果与解析计算结果相吻合。并与同参数的扁平形钢次级直线感应... 提出一种新型钢次级弧形直线感应电动机,采用多层行波电磁场理论建立该电机的区域模型,推导出法向力计算公式,建立该钢次级弧形直线感应电动机三维瞬态有限元仿真模型,仿真结果与解析计算结果相吻合。并与同参数的扁平形钢次级直线感应电动机作比较,结果表明这种钢次级弧形直线感应电动机在不改变推力的前提下能够减少法向吸力,提高推力与吸力比值,为该类电机的性能计算、优化设计奠定理论基础。 展开更多
关键词 弧形直线感应电动机 区域模型 法向力 三维瞬态有限元模型
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基于归一化的抗几何攻击三维模型水印算法
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作者 金鑫 肖俊 王颖 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第A01期215-219,共5页
为了提高三维网格水印抵抗几何攻击的能力,借用数字图像归一化的思想,提出了一种基于归一化的抗几何攻击三维模型数字水印算法.该算法在嵌入水印前将模型的几何中心移到坐标原点以实现对平移攻击的不变性;将模型由直角坐标转化为球坐标... 为了提高三维网格水印抵抗几何攻击的能力,借用数字图像归一化的思想,提出了一种基于归一化的抗几何攻击三维模型数字水印算法.该算法在嵌入水印前将模型的几何中心移到坐标原点以实现对平移攻击的不变性;将模型由直角坐标转化为球坐标,以模型顶点到几何中心的距离这一全局几何特征为嵌入单元,通过修改归一化距离的离散余弦变换系数嵌入水印,以实现对缩放攻击的鲁棒性.仿真结果表明,基于归一化的三维网格模型水印算法复杂度较低,能够很好地解决模型针对缩放攻击需要重定位的问题,在经受平移、旋转、缩放、剪切、网格简化等常见攻击时也具有较好的鲁棒性. 展开更多
关键词 数字水印 三维模型 归一化 几何攻击 鲁棒性
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3S技术在校园基础测绘与数字化建设中的应用——以伊犁师范大学为例 被引量:4
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作者 陈万基 赵阳 +2 位作者 丁第盛 阿布都布热汗·苏力坦 向宇航 《测绘与空间地理信息》 2022年第7期19-22,共4页
3S(GIS、RS、GNSS)技术现已成为测绘领域、三维空间数据获取的重要技术手段。校园基础测绘是校园数字化的第一步,其目的是采集基础地理信息,绘制校园矢量图,掌握校园地形数据,为数字化建设提供矢量数据;校园数字化建设是为校园地表地物... 3S(GIS、RS、GNSS)技术现已成为测绘领域、三维空间数据获取的重要技术手段。校园基础测绘是校园数字化的第一步,其目的是采集基础地理信息,绘制校园矢量图,掌握校园地形数据,为数字化建设提供矢量数据;校园数字化建设是为校园地表地物建设可视化模型,形成基础的、可浏览的校园基础地理模型。建设地表地物的三维模型是校园数字化的主要表现方式。在对校园进行基础测绘和数字化建设基础上,对校园地表进行功能区分类,既能分析评估现行规划建设,又能为日后规划建设提供指导。现将校园功能区分为科学教研区、行政办公区、学生生活区、体育运动区、生态休闲区5个功能区,分析发现现行的校园规划符合绿色规划理念,各功能区辐射效应显著。 展开更多
关键词 3S技术 基础测绘 数字校园 三维建模 伊犁师范大学
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