A method to exchange procedurally represented 2D CAD model data using ISO 10303 STEP

Procedural models have the advantage of being easy to edit simply by changing the values of the parameters of their constructional operations. Such models are said to embody design intent, in the sense that modifications to them conform to the method of creation used by their original creator. They also comply with any constraints implied by the particular constructional operations used. This paper introduces the development and standardization process of the ISO 10303-112 specification and describes the concept of procedural 2D modeling, a method of representing procedural 2D CAD models in STEP in harmony with other STEP resources. The feasibility of procedural 2D modeling commands for the exchange of procedurally represented 2D CAD model data is demonstrated through an experiment where procedural 2D CAD model data in neutral form generated with an in-house 2D modeling system are translated to and modified in a commercial 3D mechanical CAD system.     

Encapsulation of geometric functions for ship structural CAD using a STEP database as native storage

It is difficult to support collaborative design with a conventional ship CAD system that manages design information using files. The file storage, however, can be replaced with a commercial database management system. This paper describes OpenDIS, which is an interface between the geometric modeling kernel and the DBMS. The main purpose of OpenDIS is to implement a CAD system that has the STEP database as the native storage. A prototype CAD system has been implemented using the OpenCascade geometric modeling kernel and ObjectStore, a commercial object-oriented DBMS. The STEP methodology is used for the database schema. This CAD system has been applied to the hull design process of a ship in order to verify the usefulness of the interface.     

OpenPDM-based product data exchange among heterogeneous PDM systems in a distributed environment

In a global product development environment, more and more companies are implementing distributed engineering processes in order to shorten the time to market and merge different core competences. One of the important issues in collaborative product development during the whole product creation is to easily and quickly access the digital product definition models and documents of relevant partners. The essential problems of product data distribution are that each partner has to know what information to find in which system, how to collect the necessary information from individual systems, and how to assemble partial information so that it becomes complete. Even more difficult is the need to ensure the partner adapts to every change in the distribution model of information. To solve these problems, we propose the OpenPDM-based product data exchange method among heterogeneous PDM systems, which is a concept of a virtual data warehouse that provides data access to all partners in a distributed environment. The method is effective for partners who require real-time access to data residing in multiple heterogeneous PDM systems. We also implemented an integrated PDM system for logically linking product data which are physically distributed, and we used this system in a data exchange experiment.     

A framework for automatic creation of motion effects from theatrical motion pictures

Motion effects are the most important physical effects of commercial feature films in the latest cinemas equipped with multi-sensory-effect systems known as 4DX theaters. This paper presents a framework for automatically generating motion effects from a video. We propose a seven-step motion-effect production pipeline based on the concept of structure from motion. In particular, we present the total-variation-based adaptive noise reduction method to remove acceleration noise and introduce methods to estimate the gravity direction from an image. The proposed framework is validated by prototype application to a synthetic video, a commercial feature film, a ride film, and three point-of-view (POV) footages.     

Interfacing heterogeneous PDM systems using the PLM Services

A PDM (Product Data Management) system allows improved management of the engineering process through better control of engineering data, engineering activities, engineering changes and product configurations. There are different commercial PDM systems and each company uses a PDM that supports the company’s needs. To collaborate with parts’ suppliers, companies frequently need to interface their PDM systems with those of their suppliers. There are two ways of interface: direct translation between PDM systems and translation based on a standard format. In this study two different PDM systems are interfaced based on the PLM Services standard of OMG (www.omg.org), which is itself based on Web Services. The PLM Services enables the data exchange via the Internet. The main objective of implementation is to use the PLM Services standard for PDM data exchange via Internet.     

Solving the Shallow Water equations using 2D SPH particles for interactive applications

In this paper, we introduce a 2D particle-based approach to achieve realistic water surface behaviors for interactive applications. We formulate 2D particle-based Shallow Water equations using the Smoothed Particle Hydrodynamics. Particles defined with specific amount of water volume interplay with each other, which generates the horizon flow and the water surface motion. By the application of the particle-based Lagrangian framework to the 2D Shallow Water simulation, our method allows the water particles to move freely without being confined to a grid. The motion of the particles can represent global flow with dynamic waves covering a large area while avoiding extensive 3D fluid dynamics computation. The 2D particle-based Shallow Water equations are straightforward and computed fast with the GPU-based implementation. Experiments on a standard hardware demonstrate the performance of our approach which is running on the GPU, and the results show a realistic motion of the water surface at interactive rates.     

Sharing product data of nuclear power plants across their lifecycles by utilizing a neutral model

Many public and private Korean organizations are involved during the lifecycle of a domestic nuclear power plant. Korea Plant Engineering Co. (KOPEC) participates in the design stage, Korea Hydraulic and Nuclear Power (KHNP) operates and manages all nuclear power plants in Korea, Doosan Heavy Industry and Construction Co. manufactures the main equipment, and a construction company constructs the plant. Even though each organization has its own digital data management system and obtains a certain level of automation, data sharing among organizations is poor. KHNP obtains drawings and technical specifications from KOPEC in the form of paper. This results in manual re-work of definitions, and errors can potentially occur in the process. In order to establish an information bridge between design and operation and maintenance (O&M) phases, a generic product model (GPM), a data model from Hitachi, is extended for constructing a neutral data warehouse and the Korean Nuclear Power Plant Information Sharing System (KNPISS) is implemented.     

Representation of Urban Buildings Using Modified Relief Mapping

This paper describes the real-time mapping displacement of buildings onto the polygon model of base terrain of geo-spatial information,The buildings are represented as height maps,lcading to low memory requirements and not involving changes of the original geometry（i.e.no vertices are created or displaced）.The displacement of buildings is mapped toward the protruding direction,The base of textrue which represents the ground in topography is correctly mapped onto base polygon without any distortion.This approach can exhibit the correct,occlusions between buildings and ground due to parallax and correct self-occlusion.     

A procedural method to exchange editable 3D data from a free-hand 2D sketch modeling system into 3D mechanical CAD systems

In the concept development phase, a designer wants to rapidly create a product’s overall shape and user interfaces by making simple sketches, known as ‘thumbnail sketches’, to evaluate ideas and possibilities. Free-hand 2D sketch systems are regarded as a computerized tool for making thumbnail sketches. After the concept development phase, subsequent editing of the 3D data reconstructed from a free-hand 2D sketch with a 3D mechanical CAD system in the detail design phase is indispensable because inaccurate dimensions are inherent in a free-hand 2D sketch. For this reason, we present a new method to translate 3D data reconstructed from a free-hand 2D sketch into an editable form that reflects design intent so that the translated data can be directly used in 3D mechanical CAD systems. The feasibility of the proposed method has been demonstrated through experiments with prototype systems.