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1.
This paper will be about the question of whether or not virtual cybercrime should be regulated by means of criminal law. By virtual cybercrime I mean activities such as the stealing of virtual property or the killing of an avatar (a player's virtual representation) within the virtual worlds of computer games. One can, for example, also think of the production, distribution and possession of virtual child pornography, which does not consist of photographs or film material of real children engaged in sexually explicit conduct, but of computer-simulated children; for the images are photo-shopped or even entirely computer-generated. As the title indicates, I believe that the aforementioned question has at least four dimensions: a philosophical, a legal-economic, a pragmatic and a constitutional dimension. In this paper, I will study each of these dimensions and on the basis of my analyses I will establish criteria for the criminalization of virtual cybercrime which can be used to decide on actual cases.  相似文献   

2.
《Advanced Robotics》2013,27(1-2):165-181
To properly align objects in the real and virtual worlds in an augmented reality (AR) space it is essential to keep tracking the camera's exact three-dimensional position and orientation (camera pose). State-of-the-art analysis shows that traditional vision-based or inertial sensor-based solutions are not adequate when used individually. Sensor fusion for hybrid tracking has become an active research direction during the past few years, although how to do it in a robust and principled way is still an open problem. In this paper, we develop a hybrid camera pose-tracking system that combines vision and inertial sensor technologies. We propose to use the particle filter framework for the sensor fusion system. Particle filters are sequential Monte-Carlo methods based upon a point mass (or 'particle') representation of probability densities, which can be applied to any state space model and which generalize the traditional Kalman filtering methods. We have tested our algorithm to evaluate its performance and have compared the results obtained by the particle filter with those given by a classical extended Kalman filter. Experimental results are presented  相似文献   

3.
Since the mid 1990's, more and more college and university writing centers have been offering online synchronous writing conferences to students. Writing center researchers have published extensively on how tutors can promote collaboration in online conferences, but comparatively few have used Lev Vygotsky's conception of the zone of proximal development (ZPD) to analyze activity in these conferences or to develop specific methods for working with students in these environments. Using more recent developments in the theory of the ZPD, such as the concept of situation definition, I will discuss how tutors can apply strategies related to the ZPD to promote student learning. By focusing on students’ definitions of rhetorical concepts that often implicitly guide students’ writing processes, tutors can help students improve how they approach their writing tasks. Progress through the ZPD, then, is more related to how students grow their own understanding, rather than on the correcting of students’ texts. I will illustrate this theoretical discussion by presenting examples of two online synchronous writing conferences, and I will describe the implications and possible shortcomings of a method of tutoring that applies the concept of situation definition and the ZPD.  相似文献   

4.
It is widely accepted that embodiment is crucial for any self-aware agent. What is less obvious is whether the body has to be real, or whether a virtual body will do. In that case the notion of embodiment would be so attenuated as to be almost indistinguishable from disembodiment. In this article I concentrate on the notion of embodiment in human agents. Could we be disembodied, having no real body, as brains-in-a-vat with only a virtual body? Thought experiments alone will not suffice to answer this Cartesian question. I will draw on both philosophical arguments and empirical data on phantom phenomena. My argument will proceed in three steps. Firstly I will show that phantom phenomena provide a prima facie argument that real embodiment is not necessary for a human being. Secondly I will give a philosophical argument that real movement must precede the intention to move and to act. Agents must at least have had real bodies once. Empirical data seems to bear this out. Finally, however, I will show that a small number of aplasic phantom phenomena undermines this last argument. Most people must have had a real body. But for some people a partly virtual, unreal, phantom body seems to suffice. Yet though there is thus no knockdown argument that we could not be brains-in-a-vat, we still have good reasons to suppose that embodiment must be real, and not virtual.  相似文献   

5.
基于ARToolKit工具的增强现实交互操作研究   总被引:2,自引:0,他引:2  
增强现实是把计算机生成的虚拟图像或其它信息叠加到用户所看到的真实世界中的一种技术。ARToolKit为增强现实技术的应用提供了一种方便快捷的开发工具,但多针对于浏览展示方面。本文在ARToolKit工具下针对AVI录像文件进行增强现实的应用开发,增加了用户和现实以及虚拟物体的交互操作,通过计算机视觉的方法着重解决把虚拟物体放置到用户在视频帧上指定的点。这些将为用户使用增强现实技术进行设计和规划提供方便。  相似文献   

6.
7.
One of the challenging problems with bicycle simulators is to deal with the virtual bicycle dynamics that is coupled with rider's motion. For the virtual bicycle dynamics calculation and the real time simulation, it is necessary to identify the control inputs from the rider as well as the virtual environments. The steering, pedaling, and braking torques can be easily measured by using torque sensors and the virtual environments can be generated and provided by a visual system. However, direct measurement of the rider's net moment that significantly affects the bicycle motion is not practical. In this work, it is shown that six control forces of the Stewart platform‐based motion system can be used for effective estimation of the rider's net moment, incorporated with the sliding mode controller with perturbation estimation. © 2004 Wiley Periodicals, Inc.  相似文献   

8.
在车载通信系统中,车辆的位置信息泄露会危及驾驶员的隐私安全,而基于混合区中车辆的假名更新是实现位置隐私保护的一种有效方法。然而,现有的一些混合区方案忽略了车辆密度变化对位置隐私保护效果的影响。针对此问题,本文提出了一种支持虚拟车辆辅助假名更新的混合区位置隐私保护方案。该方案旨在根据周围合作车辆的密度不同来动态调整生成所需的虚拟车辆,并广播它们的踪迹,使攻击者无法区分虚拟车辆和真实车辆,从而实现车辆的位置隐私保护。仿真实验结果表明,该方案通过引入虚拟车辆信息,使攻击者无法区分虚拟车辆和真实车辆,有效降低了车辆真实位置或轨迹泄露的可能性,同时提高了交通密度较低情况下的位置隐私保护效果。  相似文献   

9.
This paper presents a geospatial collision detection technique consisting of two methods: Find Object Distance (FOD) and Find Reflection Angle (FRA). We show how the geospatial collision detection technique using a computer vision system detects a computer generated virtual object and a real object manipulated by a human user and how the virtual object can be reflected on a real floor after being detected by a real object. In the geospatial collision detection technique, the FOD method detects the real and virtual objects, and the FRA method predicts the next moving directions of virtual objects. We demonstrate the two methods by implementing a floor based Augmented Reality (AR) game, Ting Ting, which is played by bouncing fire-shaped virtual objects projected on a floor using bamboo-shaped real objects. The results reveal that the FOD and the FRA methods of the geospatial collision detection technique enable the smooth interaction between a real object manipulated by a human user and a virtual object controlled by a computer. The proposed technique is expected to be used in various AR applications as a low cost interactive collision detection engine such as in educational materials, interactive contents including games, and entertainment equipments. Keywords: Augmented reality, collision detection, computer vision, game, human computer interaction, image processing, interfaces.  相似文献   

10.
《Advanced Robotics》2013,27(1):7-26
Legged robots taking part in real multi-agent activities represent a very innovative challenge. This domain of research requires developments in three main areas. First, without any feedback information from the environment, there is no way for robots to achieve some tasks autonomously. Fortunately, the quadruped 'Sony' prototypes on which all experiments are carried out are equipped with an enhanced vision system; thanks to its CCD camera located in its head, the robot can obtain color images of the scene around it. Extracting relevant information from the images captured is not easy since it must be done onboard in real time. Moreover, image treatment procedures should have high process rates for the robot to react quickly in front of unexpected events. A special vision module composed of three parts has been designed for these purposes. The second point to focus on is the walking ability of the robot. Quadrupeds are designed to move efficiently and rapidly on flat ground. The objective of the walking module is to generate appropriate walking patterns allowing the machine to walk in the desired direction. Walking gaits are produced like reflexes by the robot itself to adapt to the situation. With regard to the design of these gaits, emphasis has been put on increasing speed and mastering transitions. Finally, the machine should be given a minimum of intelligence since it has to manage vision information and its walking gaits by itself. When involved in situations of cooperation or competition or both, like in a soccer game, a high-level supervision task is welcome. This paper presents detailed developments of these three points and describes how they are implemented on a real robot.  相似文献   

11.
实验数据驱动虚拟模型的方法研究   总被引:1,自引:1,他引:0  
该文提出了如何运用实验数据驱动虚拟模型进行运动仿真的新方法。该方法利用ADAMS软件在虚拟环境中构建一个已存在实体的虚拟模型 ,然后利用“导入数据的方法”将反映实体运动的实验数据加载于虚拟模型 ,从而驱动该虚拟模型按照真实物体那样运动。该文以一个受到外力和自身重力作用的小球为例 ,通过将获得的小球运动的实验数据导入的方法 ,成功驱动了小球实体的虚拟模型 ,这样就可以在虚拟环境中观察到小球的运动规律 ,从而验证了该文所提方法的正确性和可行性  相似文献   

12.
During continuous use of displays, a short rest can relax users' eyes and relieve visual fatigue. As one of the most important devices of virtual reality, head‐mounted displays (HMDs) can create an immersive 3D virtual world. When users have a short rest during the using of HMDs, they will experience a transition from virtual world to real world. In order to investigate how this change affects users' eye condition, we designed a 2 × 2 experiment to explore the effects of short rest during continuous using of HMDs and compared the results with those of 2D displays. The Visual Fatigue Scale, critical flicker frequency, visual acuity, pupillary diameter, and accommodation response of 80 participants were measured to assess the subject's performance. The experimental results indicated that a short rest during the using of 2D displays could significantly reduce users' visual fatigue. However, the experimental results of using HMDs showed that short rest during continuous using of HMD induced more severe symptoms of subjectively visual discomfort, but reduced the objectively visual fatigue.  相似文献   

13.
Synthetic Vision and Memory for Autonomous Virtual Humans   总被引:2,自引:0,他引:2  
A memory model based on ``stage theory'', an influential concept of memory from the field of cognitive psychology,is presented for application to autonomous virtual humans. The virtual human senses external stimuli througha synthetic vision system. The vision system incorporates multiple modes of vision in order to accommodate aperceptual attention approach. The memory model is used to store perceived and attended object information atdifferent stages in a filtering process. The methods outlined in this paper have applications in any area wheresimulation‐based agents are used: training, entertainment, ergonomics and military simulations to name but afew. ACM CSS: I. 3.7 Computer Graphics‐‐Virtual reality  相似文献   

14.
This article turns to genre theory's recent explorations of uptake, broadly defined as the ways genres interact, as a resource for sketching a pedagogy of shuttling between genres. Using uptake, I intend to reconceptualize multimodal compositions as a means of participating in rhetorical ecologies that consist of transactions between genres instead of thinking of remixes as an end in themselves. In this article, I first define the concept of uptake in detail and discuss its use in rhetorical genre studies. After further illustrating uptake through an analysis of transactions between YouTube parodies and the 2005 German language film Downfall, I discuss existing scholarship in multimodal composition that draws on genre but not the idea of uptake in order to lay a foundation for a pedagogy that highlights the links, feedbacks, and rules that coordinate genres. My aim in the last section is to sketch possibilities for how teachers and students can deploy the concept of uptake as a rhetorical tool to strengthen their awareness of genre and multimodality. In doing this, I hope to reposition multimodal projects as beginnings or midpoints that lead to students’ emersion into public discourse rather than culminations or end goals in themselves. Integrating studies of uptake into writing curricula in this way will help students to make sophisticated rhetorical decisions in the age of media convergence.  相似文献   

15.
Image‐based techniques have become very popular over the past couple of years. Ranging from modeling to rendering and lighting, the use of images as direct input for graphics algorithms has become as important as processing polygons or other forms of data. This talk will focus on some of the challenges posed by Image‐based relighting. Starting from a set of photographs of an object under various illumination conditions, Image‐based relighting computes novel renderings of the objects. Also, the inverse problem stated as ``What is the required lighting configuration to reach a desired illumination on the object?'' will be discussed, as well as some thoughts on how results from computer vision can be used to accelerate the process.  相似文献   

16.
本文提出了一种使用VPP对虚拟路由器数据平面加速的方法,此方法将数据平面与控制平面分开,然后将数据平面的转发工作转移到Linux用户空间下的VPP上面,并通过监听控制平面信息,实现数据平面路由表的更新.通过此种方法,可消除虚拟路由器在报文转发速率上的瓶颈,使得使用标准x86平台服务器替代专用网络设备成为可能,从一定程度上促进了网络功能虚拟化的发展,使得网络资源更加具有弹性,易于管理.  相似文献   

17.
Virtual Symposium on Virtual Mind   总被引:2,自引:2,他引:0  
When certain formal symbol systems (e.g., computer programs) are implemented as dynamic physical symbol systems (e.g., when they are run on a computer) their activity can be interpreted at higher levels (e.g., binary code can be interpreted as LISP, LISP code can be interpreted as English, and English can be interpreted as a meaninguful conversation). These higher levels of interpretability are called ‘virtual’ systems. If such a virtual system is interpretable as if it had a mind, is such a ‘virtual mind’ real? This is the question addressed in this ‘virtual’ symposium, originally conducted electronically among four cognitive scientists. Donald Perlis, a computer scientist, argues that according to the computationalist thesis, virtual minds are real and hence Searle's Chinese Room Argument fails, because if Searle memorized and executed a program that could pass the Turing Test in Chinese he would have a second, virtual, Chinese-understanding mind of which he was unaware (as in multiple personality). Stevan Harnad, a psychologist, argues that Searle's Argument is valid, virtual minds are just hermeneutic overinterpretations, and symbols must be grounded in the real world of objects, not just the virtual world of interpretations. Computer scientist Patrick Hayes argues that Searle's Argument fails, but because Searle does not really implement the program: a real implementation must not be homuncular but mindless and mechanical, like a computer. Only then can it give rise to a mind at the virtual level. Philosopher Ned Block suggests that there is no reason a mindful implementation would not be a real one.  相似文献   

18.
Behavioral and cognitive modeling for virtual characters is a promising field. It significantly reduces the workload on the animator, allowing characters to act autonomously in a believable fashion. It also makes interactivity between humans and virtual characters more practical than ever before. In this paper we present a novel technique where an artificial neural network is used to approximate a cognitive model. This allows us to execute the model much more quickly, making cognitively empowered characters more practical for interactive applications. Through this approach, we can animate several thousand intelligent characters in real time on a PC. We also present a novel technique for how a virtual character, instead of using an explicit model supplied by the user, can automatically learn an unknown behavioral/cognitive model by itself through reinforcement learning. The ability to learn without an explicit model appears promising for helping behavioral and cognitive modeling become more broadly accepted and used in the computer graphics community, as it can further reduce the workload on the animator. Further, it provides solutions for problems that cannot easily be modeled explicitly. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

19.
虚拟仿真     
新兴的虚拟仿真就是仿真回路中接入虚拟样机(VP)的数字仿真。VP可以是真实世界的实体、人体和环境的模型,因此,它可以是产品的VP、计算机生成兵力(CGF)、逻辑靶场概念、虚拟战场、功能化虚拟样机(FVP)、虚拟人、软件人、虚拟环境等等。目前,美国、日本和英国在虚拟仿真方面居于领先地位,我国起步稍晚,但也出现了一些捷足先登者。虚拟仿真的应用,十分广泛。虚拟仿真可创建和体验虚拟世界(Virtual World)。此种虚拟世界,可以是现实世界的再现,亦可以是构想中的世界,用户可借助视觉、听觉及触觉等多种传感通道与虚拟世界进行自然的交互。显然,虚拟仿真已把数字仿真置于现代科技发展的高端。  相似文献   

20.
虚拟现实辅助机器人遥操作技术研究   总被引:8,自引:1,他引:7  
刘伟军  朱枫  董再励 《机器人》2001,23(5):385-390
本文以水下机器人的遥操作作业为应用背景,提出并实现了虚拟现实技术和视觉感知 信息辅助机器人遥操作实验系统.该系统使用了CAD模型和立体视觉信息完成遥操作机器人 及其作业环境的几何建模和运动学建模,实现了虚拟作业环境的生成和实时动态图形显示. 采用了基于立体视觉的虚拟环境与真实环境的一致性校正、图形图像叠加、作业体与环境位 姿关系建立、基于网络的监控通讯等关键技术.在这个实验系统中,操作人员可利用所生成 的虚拟环境,在多视点、多窗口作业状态图形和图像显示帮助下,实时动态地进行作业观测 与机器人遥操作与运动规划,为先进遥操作机器人系统的实现提供了经验和关键技术.  相似文献   

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