Yuhua Luo

Mu3D: a causal consistency protocol for a collaborative VRML editor

This paper describes the implementation of the Mu3D application protocol and consistency control mechanisms to allow the collaborative editing of CAD design. The collaborative editor (M3D editor) developed by us is VRML compliant. The editor has been used as a base for the European Esprit project No. 26287 - M3D and the Spanish project TEL 96-0544/CODI for Cooperative CAD applications. In our system, only the changes to local databases are transmitted to other collaborative session members. To assure database consistency, the system provides consistency control over the shared data space. A great effort has been paid also to provide a high capability of cooperation and user interactivity while narrowing networks bandwidth requirements.

Real time multi-user interaction with 3D graphics via communication networks

There is a lot of development currently being carried out on cooperative visualization via communication networks. User interaction is kept to minimum in this kind of development, such as only making marks on the transmitted images, etc. There is relatively less work being done on complicated cooperative interactions, especially real-time cooperative interaction via networks. The work presented in this paper is a challenge to this type of cooperative work. The objective of the system is to allow multiple users to design a 3D scene cooperatively via communication networks in real time. The paper describes the design and communication model of the system, the design and implementation of the protocol to transmit changes in the 3D scene, the database consistency techniques and the implementation of the 3D editor interface. The current implementation status of the system shows that a real-time, full user interaction in 3D cooperative design via communication networks is achievable by our design strategy.

A prototype system for cooperative architecture design

The paper presents a prototype system for cooperative architecture design. The system includes a multi-site cooperative 3D editor and a cooperative and communication support platform. By using the prototype system, the users are able to load a design scene, modify its properties and save the result cooperatively. The online basic cooperative, interactive editing functionality on the designed objects via the communication network has been achieved.

Cooperative design for 3D virtual scenes

The paper describes a cooperative design system for a 3D virtual scene. The objective of the system is to allow multiple users to design a 3D scene cooperatively via a communication network. The system is based on a distributed layered architecture. At the application layer, a 3D cooperative design tool is implemented. The basic cooperative design operations include reading and saving a 3D scene, selecting an object from the common 3D scene, modification of the objects by geometrical transformations, modification of the attributes of the global scene or an individual object, such as, object texture, material, illumination parameters, etc. A special protocol (SMI) has been designed and implemented for the communication with the peer cooperative design tool situated on peer hosts. The session control layer and group communication layer form the cooperative support platform for the system. The session control layer is responsible for the tasks required by a cooperative working session such as service multiplexing, data consistency control, member admission etc. The group communication layer provides the point to point or point to multipoint communication. The experimental system is currently implemented on Silicon Graphics hardware platform with a 100 MB/s internal network. Open Inventor has been used for the 3D design tool. The data format is fully VRML compatible.

Visualization for cooperative architecture design system

Visualization in an online multiple user, multiple location cooperative working system for complicated 3D structures such as in architecture design is a great challenge. There are special requirements for such cooperative environment. Some of them are related to the need of multiple participants while the others are for the specific needs of the application. The paper presents the visualization scheme and its implementation for the cooperative 3D design system particularly for the application of architecture design for building construction.

CODI-a system for cooperative 3D design

A system that integrates 3D virtual scene generation tools and data communication techniques for 3D cooperative design work is presented. The system, named CODI (Sistema Cooperativo de Diseno3D) supports two major functions: 3D cooperative design and multiple client distant access. The system is implemented using Open Inventor Toolkit in C++ with VRML compatibility.

A REMOTE COOPERATIVE DESIGN SYSTEM USING INTERACTIVE 3D GRAPHICS

This paper presents a distributed system for the cooperative design in a 3D virtual environment with full interactive 3D graphics functionality. The system includes a multi-site 3D cooperative editor, a database and a cooperative support platform. The users can design and modify a common 3D virtual world from remote sites simultaneously and cooperatively via long distance communication network. The design information can be stored into the design database and retrieved from it. The cooperative and communication support platform keeps the application away from the network process detail.

Design of a cooperative working environment for mobile devices

GEMMA is a cooperative control system developed to manage and coordinate a fleet of mobile resources (boats, planes, employers, etc) dedicated to maintain clean coastal and beach waters in the Balearic Islands. All the process is supervised by a control center in several workstations. In addition, a cooperative working environment was designed and developed for a group of mobile devices. In this article we present a project extension that involves the control tasks of mobile computers. Using portable computers, PDA and mobile phones, controllers can develop their control tasks supervising the coastal state and be online with all the system and resources in the Gemma project. All the communication processes are established by TCP-IP connections via GPRS/UMTS.

An Integrated IT System for Large Scale Coastal Environment Control

The paper presents an IT system for costal environment control. The system has been fully in operation. The system collects, processes the real time environmental information and manage the mobile resources accordingly. The system includes a GIS system, a database, a web server, a communication system and the control application. The system is flexible and configurable. The system has been built with modularity, cross-platform and distributed nature.

Multimodal human-machine interface devices in the cloud

In an increasingly connected and multidisciplinary world, we propose a new paradigm of web application development. It makes the whatever modal input to use the same interface to connect to the applications. It can essentially free the web application programmers and the end users from the need of physically handling the data input devices when they are building a multimodal system. The same application can be used for a whole range of physically different peripherals, but similar from the logical point of view of data entry. This paper discusses the implementation of a pilot project, currently in a local network environment, where all the devices in the LAN are identified and described in an interface server. Users in the local network may, upon request, make use of such devices. The communication of these peripherals with the web applications will be carried out by a network of modules that run under the websocket technology. The whole process of communication and connection establishment is automatic and guided by the existing configurations in the interface server. The entire platform runs under SOA strategy and is fully scalable and configurable. Its use is not limited to games because it has much wider possibilities, interactivity in teaching, accessibility for people with special needs, adaptation of web applications to the use of uninitiated, etc.