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81.
Pan  Baiyu  Zhang  Liming  Yin  Hanxiong  Lan  Jun  Cao  Feilong 《Multimedia Tools and Applications》2021,80(13):19179-19201

3D movies/videos have become increasingly popular in the market; however, they are usually produced by professionals. This paper presents a new technique for the automatic conversion of 2D to 3D video based on RGB-D sensors, which can be easily conducted by ordinary users. To generate a 3D image, one approach is to combine the original 2D color image and its corresponding depth map together to perform depth image-based rendering (DIBR). An RGB-D sensor is one of the inexpensive ways to capture an image and its corresponding depth map. The quality of the depth map and the DIBR algorithm are crucial to this process. Our approach is twofold. First, the depth maps captured directly by RGB-D sensors are generally of poor quality because there are many regions missing depth information, especially near the edges of objects. This paper proposes a new RGB-D sensor based depth map inpainting method that divides the regions with missing depths into interior holes and border holes. Different schemes are used to inpaint the different types of holes. Second, an improved hole filling approach for DIBR is proposed to synthesize the 3D images by using the corresponding color images and the inpainted depth maps. Extensive experiments were conducted on different evaluation datasets. The results show the effectiveness of our method.

  相似文献   
82.
Zhang  Zhenning  Li  Zichen  Han  Meng  Su  Zhiyong  Li  Weiqing  Pan  Zhigeng 《Multimedia Tools and Applications》2021,80(1):575-590

Over the last few years, there has been a growing interest in augmented reality (AR) technology for education. However, current AR education applications are often used as a new type of knowledge display platform, and they cannot fully participate in educational activities to improve educational results. To enable AR technology to participate in educational activities more effectively, according to learning-by-doing theory, we explore the form of a future experimental course and propose a new AR-based multimedia environment for experimental education. The framework of the multimedia environment consists of three components: the AR experiment authoring tool, the AR experiment application, and the management application. In this AR-based multimedia environment, teachers can independently create AR experiments using the what you see is what you get (WYSIWYG) editing method. Students can manipulate the AR-based experimental object to complete the experiment in class. Moreover, teachers can observe students’ experimental behaviour, obtain evaluations in real time, and even guide students remotely. We also present an application case of a chemistry experiment and obtain results of the usability test, demonstrating improvements in AR technology participation in educational activities.

  相似文献   
83.
本文针对排放的工业废气进行连续自动的检测,设计了一种工业废气远程监测系统.该系统以单片机为主控,设计了气体传感器检测电路、废气温湿度数据采集电路、光照强度采集电路等,可实现对工业园区的废气的连续自动检测.把测量的结果通过网络发送到服务器上位机中,在系统中还可以实现对多个检测点的在线监测.实际测试结果表明,该系统可有效地监测到有害气体,达到实时预警的目的.  相似文献   
84.
蔡莉  潘志刚  陆异晨 《计算机时代》2021,(1):117-119,123
高校是"最多跑一次"思想的有力支持者,目前已有百余所高校同步推进,且取得显著成效.在此背景下,从高校留学生群体入手,分析当前高校智能咨询系统在"最多跑一次"实施落地过程中存在的问题.通过加强团队建设、规范事项、梳理流程、细化颗粒度的方式弥补仅靠系统带来的不足,旨在更好的为高校"最多跑一次"服务.  相似文献   
85.
86.

This paper presents a position control strategy for a planar active-passive-active (APA) underactuated manipulator with second-order nonholonomic characteristics. According to the structural characteristics of the planar APA system, we divide the system into two parts: a planar virtual Pendubot (PVP) and a planar virtual Acrobot (PVA). For the PVP, we mainly fulfill the target angle of the first link, which is calculated through the geometry method, and make the system stable. In this stage, via keeping the states of the third link being zero, the system is reduced to the PVP. Meanwhile, we design an open-loop control law based on the nilpotent approximation (NA) model of the PVP to make the second link stable and the first link stabilize at its target angle. Then, the planar APA system is reduced to a PVA with all links’ angular velocities being zero. For the PVA, we mainly realize the other two links’ target angles obtained via the particle swarm optimization (PSO) algorithm. Thus, the control objective of the planar APA system is achieved. Finally, above control strategy is verified by simulation results.

  相似文献   
87.

Unlike a fully-actuated manipulator, the position-posture control of a planar underactuated manipulator (PUM) is more difficult, but the research on it is significant due to the wide practical applications. The existing control methods consider no external disturbance and are involved in the staged control idea, bringing the problems of nonsmooth control torque and time-consuming. A novel one-stage control approach is proposed in this paper for the position-posture control of a three-link PUM with the first free joint under the external disturbance. By analyzing the coupling relationship between its active joints and free joint, the position-posture control is transformed into the trajectory tracking control. Unlike the general trajectory planning, the trajectories of the active joints are planned to include several parameters. Meanwhile, the parameters are solved using a chaos particle swarm optimization algorithm to guarantee that all joint angles can reach to their desired angles. Then, to obtain the high trajectory tracking accuracy at every moment under the external disturbance, the nonlinear disturbance observer is constructed and a nonlinear fast terminal sliding mode tracking controller is designed. Finally, the feasibility and superiority of this strategy are verified via two simulations.

  相似文献   
88.
Blockchain has recently emerged as a research trend, with potential applications in a broad range of industries and context. One particular successful Blockchain technology is smart contract, which is widely used in commercial settings (e.g., high value financial transactions). This, however, has security implications due to the potential to financially benefit froma security incident (e.g., identification and exploitation of a vulnerability in the smart contract or its implementation). Among, Ethereum is the most active and arresting. Hence, in this paper, we systematically review existing research efforts on Ethereum smart contract security, published between 2015 and 2019. Specifically, we focus on how smart contracts can be maliciously exploited and targeted, such as security issues of contract program model, vulnerabilities in the program and safety consideration introduced by program execution environment. We also identify potential research opportunities and future research agenda.  相似文献   
89.
由于多视无人机影像拼接时误差的传播和累计经常导致拼接图扭曲偏斜或者拼接的失败.针对这个问题提出了构建拼接环并以多级拼接作为辅助的拼接策略.首先将待拼接图像分为多组,每组中以环形方式进行拼接,然后利用SIFT进行匹配,RANSAC实现误匹配的去除,而后计算透视变换关系,最后通过平差方程将误差削弱.通过实拍无人机影像进行的拼接实验表明该方式可以有效减少累计误差的影响,提高拼接精度.该方法的提出可以作为影像拼接消除累计误差的有效方式之一.  相似文献   
90.
马钢的生存发展与职工的生存发展息息相关、浑然一体。只有企业得到发展壮大,每一名员工才能得到更好的发展,也只有员工的积极参与和努力奋斗,才能有企业的日益强大。从现实而言,为应对钢铁"去产能"压力,增强国有企业活力,就必须贯彻落实党的十八大精神,落实供给侧改革措施,踏踏实实地加强和完善国有企业党的工作和群团工作,在工作中不断创新和改革。动员和带领全体员工,激发创新活力,就是要使"人民对美好生活的向往"的奋斗目标具体化,就是建设"美丽安徽"、"幸福社区"和"幸福企业"。立足岗位开展"奋力求生存、携手保家园"活动。  相似文献   
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