燃气轮机叶片360°轮廓高精度测量

为了寻找一种既能满足叶片测量精度要求,又能解决叶片高精度测量成本高、测量效率低的测量方法,通过搭建基于相位测量的三维轮廓测量系统,对叶片进行360°测量,由于采集的点云数据需要进行数据融合,设计了一种基于相位测量轮廓方法的多角度点云数据融合机械装置,提出了基于参考平面数据旋转的新算法,最终实现了旋转多角度叶片三维轮廓点云数据高精度的自动融合,得到了完整清晰的叶片三维表面轮廓。同时对叶片局部大曲率部位进行测量,为局部二次因素的详细实验测量提供了有利条件。实验结果证明相位测量轮廓术应用于叶片三维轮廓测量非常具有实际价值。     

Optimal periodic control: The π test revisited

The paper examines second-order conditions for both steady-state and dynamic optimality in a periodic control problem. It centers on the π condition of Bittanti, Fronza, and Guardabassi [2] and has three main objectives: 1) to form a π "test" for a somewhat more general problem than considered in [2]; 2) to point out that certain auxiliary conditions must be added if the results of [2] are to be valid; and 3) to explore more fully the relationships between second-order conditions for steady-state optimality and second-order conditions for optimality in the dynamic problem.     

The high-frequency Π-criterion for retarded systems

A test for local properness in optimal periodic control of functional differential (including delay differential) equations is proven. If it is satisfied, the performance near an optimal steady state can be improved by controls and trajectories of sufficiently high frequencies.     

High‐resolution 360 Video Foveated Stitching for Real‐time VR

In virtual reality (VR) applications, the contents are usually generated by creating a 360° Video panorama of a real‐world scene. Although many capture devices are being released, getting high‐resolution panoramas and displaying a virtual world in real‐time remains challenging due to its computationally demanding nature. In this paper, we propose a real‐time 360° Video foveated stitching framework, that renders the entire scene in different level of detail, aiming to create a high‐resolution panoramic Video in real‐time that can be streamed directly to the client. Our foveated stitching algorithm takes Videos from multiple cameras as input, combined with measurements of human visual attention (i.e. the acuity map and the saliency map), can greatly reduce the number of pixels to be processed. We further parallelize the algorithm using GPU to achieve a responsive interface and validate our results via a user study. Our system accelerates graphics computation by a factor of 6 on a Google Cardboard display.     

360STYLE

记得当年微软曾经承诺过,X360会有十年生命力。如今X360步入第8个年头,后续机种XboxOne已经推出,不过按照以往的惯例,X360再撑两年应该问题不大,也就是说十年之说并非虚构。微软说未来X360还有一百多个游戏,     

360Style

Xbox One的发售日终于确定了—-2013年11月22日!除此之外,在科隆游戏展上微软也公布了有关Xbox One的更多特性,从Kinect One到Smartglass应有尽有。     

360Style

随着PS4和Xbox One发售日的临近,微软最近又公布了不少有关Xbox One性能的情报。首先是Xbox One将支持4K分辨率的游戏,这一功能目前只有Xbox One能做到。当然这并非强制措施,不过可以想象的是微软以后可以从自家游戏着手来炫耀Xbox One的优势。另外就是在一次内部会议中,     

Quantitative Comparison of Bilateral Teleoperation Systems Using μ-Synthesis

This paper presents a quantitative comparison framework for bilateral teleoperation systems (BTSs) that have different dynamic characteristics and sensory configurations for a given task-dependent performance objective (TDPO). mu-synthesis is used to develop the framework since it can efficiently treat systems containing uncertainties and disturbances. The framework consists of: 1) a feasibility test and 2) a comparison methodology using prioritized TDPOs. As the formulation used is based on mu-synthesis, the system, operator, and environment models are represented in the form of linear nominal models with frequency-dependent multiplicative uncertainties. This framework is applied to a BTS including an uncertain human operator and environment in a practical case study. The validity of the proposed quantitative framework is confirmed through experiments. The proposed framework can be used as a tool to design BTSs, especially when there are constraints in designing drive mechanisms and choosing sensory configurations.     

A Generalized Cubemap for Encoding 360° VR Videos using Polynomial Approximation

360^° VR videos provide users with an immersive visual experience. To encode 360^° VR videos, spherical pixels must be mapped onto a two‐dimensional domain to take advantage of the existing video encoding and storage standards. In VR industry, standard cubemap projection is the most widely used projection method for encoding 360^° VR videos. However, it exhibits pixel density variation at different regions due to projection distortion. We present a generalized algorithm to improve the efficiency of cubemap projection using polynomial approximation. In our algorithm, standard cubemap projection can be regarded as a special form with 1st‐order polynomial. Our experiments show that the generalized cubemap projection can significantly reduce the projection distortion using higher order polynomials. As a result, pixel distribution can be well balanced in the resulting 360^° VR videos. We use PSNR, S‐PSNR and CPP‐PSNR to evaluate the visual quality and the experimental results demonstrate promising performance improvement against standard cubemap projection and Google's equi‐angular cubemap.     

基于多角度分割的 360 全景图的显著性检测

与常规 2D 图像不同,360 全景图包含当前空间的全部视觉信息,因而在视频监控 和虚拟现实等领域有着广泛的应用,然而用户在某一时刻只能观看到一定的视角,因此,360 全景图的显著性区域检测对于视角预测至关重要。为此,提出了多角度分割的 360 全景图的显 著性检测。首先将全景图进行多角度分割,将分割结果分别投影到立方体上以去除一定畸变; 然后对每个立方体面通过稠密稀疏重建进行显著性计算;最后再将每个面的显著图投影到经纬 映射方式的矩形上,进行多角度融合以获得最终的显著图。通过人工标注的全景图显著区域进 行实验对比,结果表明该算法可以准确检测出 360 全景图的显著区域,并优于当前先进算法。