利用 WebGL 技术实现机房动态虚拟装配设计的可视化

本文设计并实现了一个面向机房的动态虚拟装配系统.该系统将传统的三维虚拟装配分解为二维装配和三维可视化两部分.在二维装配阶段,用户只需简单的交互操作就可完成机房的装配,配置结果记录在系统动态生成的配置文件中;在三维可视化阶段,系统根据配置文件可视化装配结果,实现虚拟装配.这种动态虚拟装配的架构有效提高了装配的效率,使装配更简捷、修改更容易.此外,该系统采用 WebGL 技术实现可视化,使得该系统的操作可全部在浏览器端完成,系统的发布和使用更加便捷.     

适用于P2P大型多人在线游戏的包聚合机制

提出一种适合于P2P大型多人在线游戏的包聚合机制。该机制基于游戏交互阈值和聚合阈值对游戏包进行聚合,减少数据包的发送次数,降低由数据包头部引起的开销,同时使用平均聚合度和平均聚合延迟对该机制进行评估。实验结果表明,该机制能够节省带宽,满足游戏对实时性的要求。     

Cooperative SLAM using fuzzy Kalman filtering for a collaborative air-ground robotic system

ABSTRACT

This paper presents a three-dimensional (3D) cooperative simultaneous location and mapping (SLAM) method for a collaborative air-ground robotic system, designed to manage an indoor quadrotor flying done together with a Mecanum-wheeled omnidirectional robot (MWOR) in indoor unknown and no GPS environments. An ORB (Oriented Fast and Rotated BRIEF)-SLAM 2.0 (ORB- SLAM 2.0) approach is used to produce a 3D map and discover the position of the indoor quadrotor simultaneously, and a particle-filter SLAM (FastSLAM 2.0) approach is employed to build the 2D map of the global environment for the MWOR. A more accurate 3D quadrotor position estimation (QPE) method for the quadrotor is proposed with the assistance of the MWOR. A cooperative SLAM using fuzzy Kalman filtering is proposed to fuse the outputs of the ORB-SLAM 2.0, FastSLAM 2.0, and QPE approaches, in order to localize the quadrotor more accurately. Both SLAM approaches, quadrotor position estimation method and cooperative SLAM have been implemented in the robotic operation system (ROS) environment. Moreover, the cooperative SLAM method is exploited to achieve landing of the quadrotor atop the MWOR. Five experiments are conducted to show the effectiveness and superiority of the proposed cooperative SLAM method.     

The Effects of Interactive News Presentation on Perceived User Satisfaction of Online Community Newspapers

Using a statewide, Web-based survey, this study examines the associations between online community news audiences' uses of interactive features offered in various news presentations and the perceived satisfaction of community news sites. In addition, the study aims to identify associations between different types of interactive news presentation styles and levels of satisfaction. Results indicate that use of interactive features is positively associated with perceived satisfaction with the exception of forums and Q&A features. Results also reveal that customization features, such as content submissions, letter-to-the-editor, and e-mail byline links, are the sole significant positive predictor of perceived satisfaction toward community news sites.     

Towards the interactive filmic narrative—“Transparency”: An experimental approach

Nowadays, the cinematographic language claims for a specific type of interpretation and understanding. The emergence of the digital image and the innovative immersive reception devices provide new and diverse possibilities of reading and interacting within the filmic narrative. That is to say, cinema is constantly reinvented and explores potential renewals within the new interactive medias. This article reflects not only on the mutations of the filmic narrative, but also on its adaptation to interactivity. It proposes, also, new models of implementation, from traditional filmic narrative towards an interactive one. The experimental project Transparency illustrates it—it is a cinematographic project, which has the main goal of studying the interactive filmic narrative. An original plot has been created and adapted to an interactive narrative structure. The project is presented under the form of an installation allowing the spectators to choose the narrative sequences of the story.     

How Does Interactivity Persuade? An Experimental Test of Interactivity on Cognitive Absorption,Elaboration, and Attitudes

We explore theoretical mechanisms by which the interactivity of a medium enhances the persuasive potential of messages, by investigating the effects of 2 different types of website interactivity—modality interactivity and message interactivity—on the nature of user engagement with messages. In a 3 (Message Interactivity: High/Medium/Low) × 2 (Modality Interactivity: Slider/Control) factorial experiment (N = 167), we discovered that modality interactivity led to more positive assessment of the interface and greater cognitive absorption, contributing to more favorable attitudes toward the website and even toward the antismoking messages. However, it reduced the amount of message‐related thoughts. In contrast, message interactivity enhanced message elaboration, leading to more positive attitudes among those with low involvement in the message topic.     

What Creates Interactivity in Online News Discussions? An Exploratory Analysis of Discussion Factors in User Comments on News Items

While the social, political, and journalistic relevance of user comments on online news items has been discussed intensively, no study has tried to examine why some online news discussions are more interactive than others. Based on the rationale of news value theory, this study argues that so‐called discussion factors in user comments indicate general relevance to later users to respond to them. Qualitative interviews with users who comment on news stories online and a quantitative content analysis of 1,580 user comments showed that the discussion factors uncertainty, controversy, comprehensibility, negativity, and personalization can explain interactivity in news discussions. Further, different technological implementations of the comment function seem to have a limited influence on the effects of these discussion factors.     

Open-loop video distribution with support of VCR functionality

Scalable video distribution schemes have been studied for quite some time. For very popular videos, open-loop broadcast schemes have been devised that partition each video into segments and periodically broadcast each segment on a different channel. Open-loop schemes provide excellent scalability as the number of channels required is independent of the number of clients. However, open-loop schemes typically do not support VCR functions. We will show for open-loop video distribution how, by adjusting the rate at which the segments are transmitted, one can provide VCR functionality. We consider deterministic and probabilistic support of VCR functions: depending on the segment rates chosen, the VCR functions are supported either 100% of the time or with very high probability. For the case of probabilistic support of PLAY and Fast-forward (FF) only, we model the reception process as a semi-Markov accumulation process. We are able to calculate a lower bound on the probability of successfully executing FF actions.     

The impact of Social Multimedia Systems on cyberlearners

The phenomenon of social learning analytics presents a synergy between variety of disciplines, such as business intelligence, educational data mining, cyberlearning, and cyber infrastructure. The main contribution of this research is to combine two types of social learning analytics, social learning network analysis and social learning content analysis in studying the impact of the Social Multimedia Systems (SMSs) on cyberlearners. The research study provided in this paper is based on the survey data collected in spring 2011 at Western Kentucky University. The evidence obtained from the analysis shows that SMS impacts (a) the digital communication between faculty and students; (b) students’ success and grades; (c) the amount of materials covered and learned; (d) the effectiveness of studying; (e) the depth of learning; (f) the ability to focus on the most important learning objectives; (g) the degree of collaboration among students; and (h) the students’ motivation of studying.     

Inspiring and Informing Citizens Online: A Media Richness Analysis of Varied Civic Education Modalities

Public deliberation on the Internet is a promising but unproven practice. Online deliberation can engage large numbers of citizens at relatively low cost, but it is unclear whether such programs have substantial civic impact. One factor in determining their effectiveness may be the communicative features of the online setting in which they occur. Within a Media Richness Theory framework, we conducted a quasiexperiment to assess the civic outcomes of interventions executed online by nonprofit organizations prior to the 2012 U.S. presidential election. The results assess the impact of these interventions on issue knowledge and civic attitudes. Comparisons of the interventions illustrate the importance of considering media richness online, and our discussion considers the theoretical and practical implications of these findings.