Catálogo de publicaciones - libros

In this research, a product model for representing steel girder bridges was developed, based on IFC of IAI. In order to control 3D objects in the CAD world effectively, first, a virtual reality (VR) CAD system was developed for engineering of steel girder bridges by using the developed product model, Java 3D, liquid crystal shutter glasses, infrared emitter unit, etc. Then, to improve the user interface, an electro-magnetic sensor system was added for controlling 3D objects in the virtual world. This system can be used for interference checking between moving girders and surrounding structures during erection. In order to enable multiple users to view the 3D bridge model from different locations and angles, a cooperative engineering environment was proposed. In this environment, each user wears a head mounted display (HMD) instead of liquid crystal shutter glasses. A prototype system is being developed for verification of the proposed methodology.

As the collaborative editing system becomes prevalent, further requirement on content based collaboration is presented by editors. This paper focuses on how to implement content based collaboration. In order to combine the advantage of nature language processing technology in content parsing, we present the shallow nature language parsing technology in collaborative editing system. This technology is based on the segmentation and the text classification. This paper also discusses the reason why the shallow nature language parsing technology is useful in content based collaboration and its further use in collaborative editing system. In addition, it has already been used in our collaborative multimedia editing system which is designed for Chinese teaching material editor. From the result of experiment, it shows that the system really reduces the time in editing collaboration.

Multi-UAV cooperative reconnaissance is one of the most challenging research area for UAV operations. The objective is to coordinate different kinds of sensor-bearing UAVs conducting reconnaissance on a set of targets within predefined time windows at minimum cost, while satisfying the reconnaissance demands, and without violating the maximum permitted travel time for each UAV. This paper presents a multi-objective optimization mathematical formulation for the problem. Different from previous formulations, the model takes the reconnaissance resolution demands of the targets and time window constraints into account. Then a multi-objective genetic algorithm CR-MOGA is put forward to solve the problem. In CR-MOGA, Pareto optimality based selection is introduced to generate the parent individuals. Novel evolutionary operators are designed according to the specifics of the problem. Finally the simulation results show the efficiency of our algorithm.

This paper presents our recent research work on Peer to Peer distributed information sharing based on mobile agent. From various perspectives, our work focuses on how to improve information retrieval efficiency in a P2P distributed information sharing system. A new model based on mobile agent is proposed and the new migration algorithm of mobile agent based on ant colony algorithm (ACA) is presented to implement P2P information retrieval. In order to evaluate and validate the model, we built a simulated P2P prototype consisting of a network of peer nodes; mobile agent migrating in the network, making peer nodes communication with each other. The results show some advantages of the proposed approach for the P2P distributed information sharing based on mobile agent.

P2P networks provide a basic form of anonymity, and the participating nodes exchange information without knowing who is the original sender. Packets are relayed through the adjacent nodes and do not contain identity information about the sender. Since these packets are passed through a dynamically-formed path and since the final destination is not known until the last time, it is impossible to know who has sent it in the beginning and who will be the final recipient. The anonymity, however, breaks down at download/upload time because the IP address of the host from which the data is downloaded (or to which it is uploaded) can be known to the outside. We propose a technique to provide anonymity for both the client and the server node. A relay node along the path between the client and the server node is selected as an agent node and works as a proxy: the client will see it as the server and the server looks at it as the client, hence protecting the identity of the client and the server from anonymity-breaking attacks.

An information integration platform is developed to transport messages, files, structural data, semi structural data, and stream media at the same time. The GPS (Global Position System) information of the vehicles can be sent to the control center by wireless communication network such as GPRS (General Packet Radio Service), CDMA (Code Division Multiple Access), Internet and Intranet. The information integration platform control center can then dispatch command and receives information from the mobile terminals. GPS, GPRS, CDMA, Internet, Intranet and M-DMB (Mobile Digital Multimedia Broadcasting) network are all integrated into the platform. Different kinds of data can be sent and received simultaneity. The stream media can replay in time. There are two key technologies in the information integration platform; one is server cluster, other is mobile terminal development.

The requirement for high-quality product with reduced cost and time-to-market in multidisciplinary project is demanding. Integration of design and process planning with computer aided techniques can provide a solution to this challenge. This paper describes a reference model of integrating computer aided techniques to aid the concurrent development of a multi-nozzle 3D printer for fabricating artificial bone scaffold at the University of Strathclyde and the Northwestern Polytechnical University. This integration reference model, including design tools such as Material Computation (MC), Computational Fluid Dynamics (CFD), and CAD, and planning tool such as CAM techniques, is employed to support this special 3D printer development. The high precision multi-nozzle development was used as a case study to validate this integration of concurrent design and process planning. CAD tools were used to provide several nozzle design concepts and a rigorous CFD analysis of several nozzle designs under the same boundary conditions were undertaken to refine and evaluate them by research staff from both institutions. This cooperative conceptual design case study demonstrated that it drastically reduced development time and cost in devising nozzle conceptual sketch design and optimizing the nozzle design for 3D printer. This makes it an important step in designing a high precision artificial bone rapid manufacturing machine.

Usability, considering user satisfaction along with the user performance, is one of the key factors in determining the success of a product in today’s competitive market. Designing usable intercity bus seats is important for passengers during the long hours of traveling. Comfort, aesthetic, safety, convenience to the body posture, durability, harmoniousness with the seat accessories and operability are expected usability dimensions of seats for both user and the designers. Aim of this study is to identify and rank ten alternative seats of an intercity bus manufacturing company according to these usability attributes. The products are evaluated by five subjects and assessed for each usability attributes by using linguistic variables. Then Fuzzy Axiomatic Design Theory (FADT), which is the combination of second axiom, is used as a multi attribute decision making tool to determine most usable seat design solution. Design range is defined by design engineers and system ranges for seats are obtained from linguistic assessment of five subjects for applying conformance testing in cooperative engineering.

Integration of product design software and automation of their execution can greatly reduce design cycle time and manufacturing cost, and significantly improve product performance, quality, and reliability. The previous approaches are control-driven integration which cannot deal with dynamic change of the environment because the controller executes a sequence of tasks according to the pre-defined workflow. In this paper, we propose a data-driven integration of engineering processes. Each BDI(Belief-Desire-Intention) agent acts autonomously according to the change of the shared data, so the proposed agent architecture can deal with dynamic change of the environment such as user’s input parameters.

Software creation, development and maintenance are activities that require a great quantity of cooperative work. In the last years, several languages to model the diverse software processes have been proposed. However, these software Process Modelling Languages (PML) have not ended up being standardized nor being implanted by a majority in industry. The so-called Process-sensitive Software Engineering Environments (PSEE) are software engineering environments with support to manage PML. Each PSEE proposed has a PML associated, so there is a clear dependence between the software engineering environment and its modelling language. In this article, the cooperative support that a PSEE should offer is analyzed, and an environment with support for software PMLs is presented. This environment provides workspaces for distributed synchronous collaboration where work teams can develop a software project.