基于线性八叉树的点云数据存贮与索引

八叉树结构是由四叉树结构推广到三维空间而形成的一种3D栅格数据结构,其树型结构在空间分解上具有很强的优势,为了有效地进行大量点云数据的存储和管理,重点讨论了线性八叉树编码技术。     

3DGIS在烟草农田管理中的应用及发展

伴随着计算机技术和GIS技术的发展,GIS技术在越来越多的行业中得到应用。介绍了三维地理信息系统（3DGIS）在烟草农田管理中的应用,展望了3DGIS在烟草农田管理中的应用前景,如结合GPS和RS技术,模拟烟草生长、烟草生产管理决策等,以提高烟草的产量。     

Sitting on the Fence: Integrating the two worlds of scientific discovery and invention within the firm

Applying a within-firm perspective to the topic of the division of innovative labor, I explore the organization of scientific discovery at the firm level — specialized or integrated with invention. Using data on inventors and authors related to U.S. publicly-traded science-performing firms for the period 1980–2015, the paper deepens our understanding of the determinants and the tradeoffs associated with the strategic choice of scientific discovery organization. I show that integration is related to a tradeoff between short-term applied R&D and long-term fundamental R&D; while integration is beneficial for invention, it has adverse effects on its scientific output, which decrease invention in the long run. The negative relationship between integration and publication reduces the direct increase in patents due to integration by approximately 90%. To better understand firms’ R&D organizational choice, I present internal and external factors that have implications on the benefits and costs associated with integration: reliance on science, stage of technology, external market for technology, and R&D spillins. Finally, I present consistent implications in terms of market value and show that value creation is related to organizational structure.     

海外研发中心促进母公司创新绩效了吗？

   本文围绕“设立海外研发中心与母公司创新绩效”的关系展开理论研究,认为海外研发中心的设立,是新兴市场国家企业在国际化战略中追赶发达国家企业的重要方式,并对于母公司创新绩效存在正向影响。在此基础上建立固定效应模型进行实证分析,选取汽车行业作为研究对象,结果证明：海外研发中心能够更好地将获取的国际资源转化为专利数量为代表的母公司创新绩效,但对专利质量为代表的母公司创新绩效的作用效果有所不同;国有控股企业因国内政策支持反而会受到东道国的某些限制,从而抑制母公司创新绩效的提升;当企业自身能力较弱,无法独立建立海外研发中心时,企业可以采用并购海外技术先进型企业并在并购企业所在地建立研发中心的方式达到事半功倍的效果。在此基础上,本文从企业层面和政府层面提出我国汽车制造业进一步创新发展的路径。     

税基还是税率？不同税收激励与企业研发创新

   创新的公共产品特性和金融市场失灵是影响企业研发创新的两个重要因素,前者可通过税收激励来调节,而后者产生的主要原因是融资约束。本文基于2010—2017年沪深两市A股上市公司数据,从融资约束视角采用双固定效应模型、动态回归模型、负二项回归模型等方法研究了税收激励对企业研发创新的影响。结果表明：税收激励对研发投入强度具有正向促进效应,而且税基优惠的促进效应大于税率优惠,但税收激励对研发创新质量的促进效应不足。融资约束对研发投入强度影响显著为负,税收激励可通过缓解融资约束提高研发投入强度,其中税基优惠主要有利于缓解内部融资约束,税率优惠更有助于缓解外部融资约束。文章最后提出应关注每项税收激励政策有效性、提升创新质量等建议。     

三维红外运动捕捉系统在田径技术诊断中的应用——以女子100m栏运动员王丽为例

利用三维红外运动捕捉系统对运动员王丽的跨栏动作进行影像捕捉、分析,揭示其现有技术动作的特点。研究发现王丽跨栏技术的特点:(1)跨栏步幅大,主要体现在起跨步步幅大,这可能对其腾空时间有影响;着地距离较短,比较合理。(2)起跨腿支撑时间和摆动腿支撑时间较短,说明其下肢肌肉较为有力,能够快速支撑其身体质量。(3)腾空时间较长。     

三米跳板跳水空中技术动作的三维运动学分析方法

旨在建立适合三米跳板跳水空中动作的三维运动学分析方法。方法:用安装于笔记本电脑的运动采集软件及其相连接的两台DV摄像机同步采集三米跳板跳水空中动作。用三维标定框架置于跳板上进行标定拍摄。用SIMIomotion运动录像分析系统解析空中动作。用前述方法考察杆状物体在3×2×7m空间范围运动时所解析获得长度的误差。结果:解析获得运动员头部、颈、腕关节、肘关节、肩关节、躯干中心点、髋关节、膝关节、踝关节、跳板等关键点的三维位移和速度。同时获得运动员质心的位移和速度,腾空时间,起跳角度等关键技术指标。误差分析表明,本方法最大误差小于3%。结论:本研究建立了三米跳板跳水三维运动学分析的有效方法。     

广义基本有限生成的TS1-模的性质

定义了广义基本有限生成的TS1-模.主要证明了广义基本有限生成的TS1-模的广义基本有限生成的type子模是广义基本有限生成的TS1-模;M是广义基本有限生成的TS1-模当且仅当对M的任意广义基本有限生成子模N,存在KIM,使得N≤geK.     

Through the Dąbrowski Lens: A Fresh Examination of the Theory of Positive Disintegration

D?browski’s theory of positive disintegration is an emotion-centered, nonontogenetic, five-level theory of personality development where the experience of all emotions is essential for the process of growth. In this article, we examine the complexities of the three factors of development, which are essential to the notion of development within the theory of positive disintegration. We elaborate on the relationships between these factors, depict the processes and interactions in a new graphical framework, provide associated explanations, and support these by additional references to D?browski’s original writings.     

Why 3D Print? The 21st-Century Skills Students Develop While Engaging in 3D Printing Projects

The emergence of 3D printing has raised hopes and concerns about how it can be used effectively as an educational technology in school classrooms. This paper presents the results of a survey asking teachers from multiple grade levels and subject fields about the impact of 3D projects on student learning. Teachers were asked about the kinds of 3D projects they were doing with students and what skills or knowledge students were developing by participating in those projects. Participants reported that their students developed a number of skills while working on 3D printing projects, including 3D modeling, creativity, technology literacy, problem-solving, self-directed learning, critical thinking, and perseverance. Parallels between teacher-identified skills and widely cited lists of 21^st-century skills suggest that 3D projects are a promising approach to preparing students for life and work in a digital age.