基于Web的3D技术--X3D与VRML97

X3D是一种基于Web的交互式三维文件格式标准．相比它的前身——VRML97，X3D在多方面做了巨大改进．本文分析对比了X3D和VRML97两种标准各自的特点．     

Discovery of Non- D(D) Decays of Ψ(3770) Particle Lying Above D(D)Threshold and Studies of D Meson Decays at the BES-Ⅱ

Particle physics is the study of the fundamental particles and their fundamental interactions.These fundamental particles are six quarks (u, d, s, c, b and t)and six leptons (e, ve, μ, vμ, τ, vτ) which serve as the blocks for building up the matter in the universe.The elementary theory of the particle physics - the Standard Model (SM)includes both the electroweak theories and the quantum chromodynamics (QCD).Breakthroughs in the electroweak theories have been awarded by three Nobel Prizes, and the QCD has been also honored with the Nobel Prize for its prediction about the particle interaction at high energy.However, the lattice QCD (LQCD) and other QCD effective theories for describing the interaction at lower energy still need to be experimentally tested.     

基于OpenGL的三维图形绘制和3D建模

介绍了利用OpenGL实现三维图形绘制的基本编程框架和方法,对OpenGL中光照、材质、投影等关键技术的应用方法进行了重点阐述。简要介绍了利用3D Studio Max构建复杂模型,以降低用OpenGL构造复杂模型难度、减少建模工作量的方法。     

Instance-prototype similarity consistency for unsupervised 2D image-based 3D model retrieval

The unsupervised 3D model retrieval is designed to joint the information of well-labeled 2D domain and unlabeled 3D domain to learn collaborative representations. Most existing methods adopted semantic alignment, but were inevitably affected by false pseudo-label. In this paper, we design a novel Instance-Prototype Similarity Consistency Network (IPSC) to guide domain alignment with similarity consistency, which can simultaneously suppress the impact of false pseudo-label information and well reduce the domain discrepancy. IPSC contains two similarity strategies, named Single instance vs Multiple prototypes and Instance-pair vs Single prototype. The first strategy utilizes a single instance as an anchor, and measures the similarities between the anchor and multiple prototypes with the same category but from different domains. The minimization between these similarities can better align the cross-domain prototypes with Kullback–Leibler (KL) divergence than traditional Euclidean similarities. The second strategy utilizes a single prototype as an anchor, and measures the similarities between this anchor and an instance-pair with the same category but from different domains. The minimization between these similarities can conduct the instance-level alignment with KL divergence, which can better suppress the negative effect of noisy pseudo-labels. We conduct various experiments on two datasets, MI3DOR-1 (21000 2D images and 7690 3D models) and MI3DOR-2 (19694 2D images and 3982 3D models), to verify the superiority of our algorithm.     

数字电视3D技术及3D视频传输格式

随着生活水平的提高,人们对于感官享受的要求也越来越高.在2009年6月3D电影《阿凡达》上映之后,一时间好评如潮.之后,各大彩电厂商纷纷推出了全新的3D电视和3D蓝光播放器,3D显示技术的发展迎来了新的高潮.越来越多的3D视频应用正在进入我们的生活环境并改善我们的生活方式.HDMI标准的最新版本1.4a为家庭影院欣赏3D视频,以及定义3D显示设备与讯源设备经HDMI连接交换信息的输入/输出协议,建立了十分重要的基础架构.     

Unsupervised self-training correction learning for 2D image-based 3D model retrieval

Existing 2D image-based 3D model retrieval (IBMR) methods usually use the pseudo labels as semantic guidance to reduce the domain-wise and class-wise feature distribution difference across annotated 2D images and unlabeled 3D models. However, they cannot entirely guarantee the quality of pseudo labels, which will decrease prediction discriminability and diversity to affect feature distribution alignment. Therefore, we propose a novel unsupervised self-training correction learning (USTCL) network for the IBMR task. Specifically, we first utilize a CNN to encode 2D images and 3D models (described as multi-view images). Then, we design a noise-corrected self-training learning module (NCST) to denoise pseudo labels in an adversarial manner to make the predicted categories more easily discriminated to improve prediction discriminability. Besides, we employ a target-guided pseudo label refining strategy (TPLR) to progressively refine generated pseudo labels to prevent minority categories from being pushed into majority categories, thereby enhancing prediction diversity. Comprehensive experiments on popular IBMR benchmarks validate the effectiveness and robustness of USTCL, e.g., it can achieve the average gains of 54.20%/22.30%, 62.17%/43.21%, 54.21%/31.18%, 63.48%/43.28%, 59.87%/44.49% in terms of NN, FT, ST, F-measure, DCG and the decrease of 29.50%/35.15% corresponding to ANMRR on MI3DOR (21,000 2D images and 7,690 3D models) and MI3DOR-2 (19,694 2D images and 3,982 3D models), respectively.     

基于单张二维图像的三维建模研究

对基于单张二维图像重建三维模型问题进行深入研究,对目前使用的方法进行比较分析,提出了基于紧水平支集的S FS三维模型重建方法。首先改进了基于快速匹配算法求解的紧水平支集方法,以提高紧水平支集求解的精度和效率,并将此方法应用到求解S FS问题,提出基于水平集快速求解S FS问题的方法;接下来为解决S FS固有的凹凸二义性问题,基于分水岭的思想寻找凹凸分界线,以此确定产生凹凸二义性的区域用以进行重建;最后利用拓扑变换重构凹陷区域,得到正确的三维模型。     

最新3D新知

美国IMAX 3D电影院最近上映的新作“海底世界”深受好评，栩栩如生的3D立体画面，让许多观众忍不住地伸出手，想要触摸从身旁游走的缤纷热带鱼。IMAX 3D影片是目前世界上最逼真的立体电影，在场的观众将犹如身历其境。然而制作及播放IMAX 3D影片所需的设备，包含20x27m超大3D屏幕、拍摄立体画面的摄影机，以及投射立体画面至     

浅谈维生素D

文章论述维生素D的性质及其应用,并对存在的问题进行了一些浅谈,提出了一些意见。     

3D aerogels from hybrid 2D materials:ultralight and flexible superinsulators

<正>Advances in research and technology to boost human space exploration proceed at a brisk pace,although a major obstacle remains:the cold and empty outer space.Can we capitalize on the unique properties of specific materials and structures to address this problem?Considered among the best insulating materials available,aerogels have become prime candidates in this field owing to their ultralight weight,large surface area,     

基于开源Web 3D引擎的三维系统的开发

应用Web3D引擎开发的计算机仿真系统或虚拟现实系统均需在Web浏览器上运行,需要其能快速下载和运行,并且尽量不需下载特定插件。采用基于JAVA技术的开源Web3D引擎开发的三维系统可以满足上述要求,开发的展示系统可以实现三维图形的旋转、缩放等交互功能。此外,在系统开发过程中对引擎中不完善的部分进行了必要的修正。     

Significance of Vitamin D Binding Protein in Assessing Vitamin D Status Among Under-Five Children

Despite ample sunshine, 50–90% Indian children have Vitamin D deficiency (VDD). This enigma of widespread VDD needs exploration especially among under-fives as physiological variations in Vitamin D Binding Protein (VDBP) levels could be potential confounders in the interpretation of total 25-hydroxyvitamin D [25(OH)D]. However, there is scarce information about relevance of VDBP levels in under-five age group. We therefore, explored association of VDBP levels among 1–5 year old children with VDD. Serum levels of 25(OH)D, VDBP, calcium, parathyroid hormone (PTH) and alkaline phosphatase were estimated in 210 apparently healthy children in the age group of 1–5 years. VDD was defined as serum 25(OH)D levels < 20 ng/ml as per the IOM classification. VDBP levels were classified as low if levels were < 168 μg/ml as per the kit. The prevalence of VDD was 79.5% (n = 167) and VDBP levels were low in 48.6% (n = 102) of children. 25(OH)D levels correlated positively with VDBP (r = 0.298, p = 0.0001). A significant number of children (52.7%) with VDD had low VDBP (p = 0.015). and despite adequate sun exposure, 43% of children showed VDD and 56.6% had low VDPB levels. The low VDBP levels largely explain low 25OHD levels without necessarily implying VDD. It may add a new dimension for better understanding of widespread VDD among under-five children. It thus, points towards the need for redefining cut offs and complete evaluation of vitamin D status among under-fives including VDBP.     

跨国公司对华R＆D投资及中国R＆D策略分析

伴随着经济全球化,特别是中国加入WTO后,许多世界知名跨国公司纷纷将其研发中心迁至中国。在这样的背景下,中国一方面要加强国内R＆D储存,另一方面应积极吸纳跨国公司R＆D溢出,从而更好地发展中国经济。     

立体电影大反击

过不了多久，神奇的立体电影就将重出江湖，而这次它将不再需要上世纪70年代那种让人头疼的立体眼镜了。卢卡斯、斯皮尔伯格、卡梅隆和其他好莱坞电影人已经准备好永远告别二维世界了。[编者按]