Immersive Interaction

Non

The 3D Sketch Slice: Precise 3D Volume Annotations in Virtual Environments

In the oil and gas application domain, there is a need for 3D volume annotations to sketch out uncertainty regions in seismic data sets. Together with geo-science experts, we identified actual requirements for efficient annotations of volumetric areas. As a result, we introduce the 3D Sketch Slice, a novel system for volumetric annotations. Based on a 3D-tracked pen tablet, the 3D Sketch Slice works as a prop for a subsurface volume slice. Using pen input, a user can precisely sketch 3D points on a 2D volume slice while directly controlling the 3D position and orientation of that slice within a seismic volume. The points selected define 3D sketches through 3D alpha shape representations. Furthermore, we define clutching and mapping functions and we present a novel visual feedback method for multi-user annotations. Finally, we performed an informal evaluation with expert users. Despite some ergonomic concerns, they confirmed an increase in perceived precision. In general, the requirements identified had been met and it was proposed to apply the 3D Sketch Slice methodology to other scenarios

Is the Web a Secure Enviroment for Electronic Commerce?

Abstract The Internet is a world-wide network of computers. Currently, there are about 30 million people using the Internet, and approximately one million new users log on each month. The Internet consists of many parts, but the two most popular are the World Wide Web (WWW) and electronic mail (e-mail). What hinders the rest of the world to connect to the Internet and its popular applications and services? Three reasons have to be mentioned: connectivity, costs and last but not least anxieties. Some people see the Internet as a collection of hackers trying to attack the privacy, confidentiality and even property of individuals, companies, and organizations. This hinders them to join the Internet world at all or this makes them rely on and trust in doubtful security policies in a world where overall security is not possible. Unfortunately this is also true for many businesses. This paper overviews conventional and extraordinary security threats and measures especially related to the World Wide Web. It shows that security is relative and that the balance between convenience and protection is hard to find. In consequence, the Internet does not offer more security than normal life and one has to go a certain risk to benefit from its potential

Securing Ordinary TCP Services through Tunnels

Many popular protocols deployed in the Internet today, have been designed years before security, cryptographic authentication and data encryption was an issue. Examples for such protocols are POP, telnet, X11remote -display, and FTP. These protocols are to be considered insecure nowadays and if we were living in an ideal world, they would have been replaced by more sophisticated protocols completely. In fact, though, Internet services based on these protocols are used more than ever before, because of the widespread availability of implementations for all platforms and operating systems. A large organization or company can not afford to discontinue services like POP or FTP, because so many of their members or employees are using them. The solution for this dilemma is to tunnel the insecure protocols through secure channels, which are protected by strong cryptography. Even though software for this purpose is widely available already, the Secure Shell (SSH) for example, exp..

Quality of Service in a Multimedia Environment

Engineers and Managers today are co-operating in a multimedia environment buying network services from a variety of service providers. Quality of Service is an important issue for them. In order to avoid extra costs, the handling of Quality of Service has to be considered as an integral part of quality management. The International Organisation for Standardisation's ISO 9000, on the other hand, provides guidelines which can be used by manufacturers and service providers to establish a quality-conscious approach for development, testing, manufacturing and support operations. In such a case ISO 9000 certification represents a first step in the process of improving quality. Quality of Service is well-defined in the different protocol layers, but the standard ISO 9000 does not immediately help in the area of groupware, CSCW or multimedia applications. The problem is that those quality standards are more related to the quality management and not to the product or service quality itself whic..

1 Abstract Service Level Management with Agent Technology

The essential aspect of the global evaluation of a service is the opinion of the users of the service. The result of this evaluation expresses the users ‘ degrees of satisfaction [ITU94]. This paper will outline a generic evaluation methodology for multimedia applications like e-mailbased services, the World Wide Web (WWW), and real-time applications. It concentrates on the application layer and the services aspects. Principles of software evaluation can be used for quality assessment and measurement for networked services and distributed applications. A specific method for measuring important service characteristics is therefore presented. The method and the measurement procedure allows to compare the actual characteristics of service quality with the required characteristics and thresholds. The approach can easily and efficiently be implemented in any organization with other applications too. The proof of concepts will be made by the implementation of quality measurement agents following the quality assessment and measurement methodology for different distributed applications outlined in this paper. Our approach of performing service level management with agent technology is distributed, slim, minimizable to the maximum, and independent in its methodology. Finally it offers comparable, objective results. This paper is not about [M.3010] or [X.711]. It is for end users and (competing) service providers trying to get comparable measurement results by applying common measurement methods and by concentrating on a well-defined subset of quality characteristics

A Two-User Virtual Environment for Rapid Assembly of Product Models Within an Integrated Process Chain

In this paper we present an ongoing research work dedicated to a Virtual-Reality-based product customization application development. The work is addressing the problem of flexible and quick customization of products from a great number of parts. Our application is an effective instrument that can be simultaneously used by two users for rapid assembly tasks, allowing engineers and designers to work collaboratively. Furthermore, it is directly connected to a manufacturing environment, which is able to produce the product right after customization. In the paper we describe the architecture of the application, our interaction and assembly techniques, and explain how the system can be integrated into a manufacturing environment