• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.699-722
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• 2019

It is difficult to observe the potential risks of lifting or turn-over operations in the early stages before a real operation. Therefore, many dynamic simulations have been designed to predict the risks and to reduce the possibility of accidents. These simulations, however, have usually been performed for predetermined and fixed scenarios, so they do not reflect the real-time control of an operator that is one of the most important influential factors in an operation; additionally, lifting or turn-over operations should be a collaboration involving more than two operators. Therefore, this study presents an integrated method for a collaborative simulation that allows multiple workers to operate together in the virtual world. The proposed method is composed of four components. The first component is a dynamic analysis that is based on multibody-system dynamics. The second component is VR (virtual reality) for the generation of realistic views for the operators. The third component comprises the control devices and the scenario generator to handle the crane in the virtual environment. Lastly, the fourth component is the HLA (high-level architecture)-based integrated simulation interface for the convenient and efficient exchange of the data through the middleware. To show the applicability of the proposed method, it has been applied to a block turn-over simulation for which one floating crane and two crawler cranes were used, and an offshore module installation for which a DCR (dual-crane rig) was used. In conclusion, the execution of the proposed method of this study is successful regarding the above two applications for which multiple workers were involved.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.3
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• pp.1-14
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• 2019

Cooperative systems among various unmanned vehicles are widely used in various field and emerging. Unmanned vehicles are able to operate various missions without operator onboard and they are highly stable. Collaborative work of multiple unmanned vehicles is emphasized due to the difficulty of recent missions such as SEAD (Suppression of the Enemy Air Defenses), MUSIC (Manned Unmanned Systems Integration Capability), goldentime in the rescue mission. In this study, ROS and Pixhawk were proposed as a method of construction of a collaboration system and framework for an integrated simulation environment for heterogeneous unmanned vehicles is proposed. Totally 5 unmanned vehicles were set for the simulation for the observation of illegal fishing boats. This paper shows the feasibility of the cooperative system using ROS and Pixhawk through the simulation and the experiment.

• Korean Journal of Computational Design and Engineering
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• v.8 no.4
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• pp.231-242
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• 2003

Multidisciplinary Design Optimization (MDO) is an optimization technique considering simultaneously multiple disciplines such as dynamics, mechanics, structural analysis, thermal and fluid analysis and electromagnetic analysis. A software system enabling multidisciplinary design optimization is called MDO framework. An MDO framework provides an integrated and automated design environment that increases product quality and reliability, and decreases design cycle time and cost. The MDO framework also works as a common collaborative workspace for design experts on multiple disciplines. In this paper, we present the architecture for an MDO framework along with the requirement analysis for the framework. The requirement analysis has been performed through interviews of design experts in industry and thus we claim that it reflects the real needs in industry. The requirements include integrated design environment, friendly user interface, highly extensible open architecture, distributed design environment, application program interface, and efficient data management to handle massive design data. The resultant MDO framework is datasever-oriented and designed around a centralized data server for extensible and effective data exchange in a distributed design environment among multiple design tools and software.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.9
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• pp.142-150
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• 2003

MDO is one of the efficient methods for huge and multi -functional system design. This paper describes a design collaboration framework with MDO in networked design environment. A prototype of web -based integrated design system was implemented to show sharing and exchange of models and analysis information between MDO modules and collaborative design stations. Server System consists of MDO modules for optimization and modeling module for 3D modeling operation. Client system provide user with graphic interface for shape modeling and system operation. We believe that the proposed approach can be extended to solve real complex multidisciplinary design problems.

• Korean Journal of Computational Design and Engineering
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• v.9 no.3
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• pp.260-265
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• 2004

This paper proposed a Web-based training service for product data management by supporting an integrated product data management system, various technical documents. and efficient communication systems. It also supports a general product development process and a consistent product data model that enable participants to experience management of consistent product information during the product development life cycle. The Web based environment of the service also provides participants with a collaborative workplace with other participants and a Web portal for all the components of the service.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.65-70
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• 2005

This paper introduces an approach to multi-layered product knowledge model for collaborative engineering environment. The participants in collaborative engineering want to share and reason product knowledge through internet without any heterogeneity and ambiguity. However the previous knowledge models are limited in providing those aspects. In this paper, the collaborative engineering domain is analyzed and then the product knowledge is organized into four levels such as product context model, product specific model, product design model and product manufacturing model. The four levels are represented by first-order logic in layered fashion. The concepts and the instances of a formal ontology are used for recursive representation of the four levels. The instances of the concepts of an upper level like product context model are considered as the concepts of an adjacent lower level like product specific model, and this mechanism is applied to the other levels. These logic representations are integrated with the schema and the instances of a relational database. OWL representation of the four levels is defined through the integration of the logic representation and OWL primitives. The four product knowledge models have their major representation according to the characteristics of each model. This approach enables engineer to share product knowledge through internet without any ambiguity and utilize it as basis for additional reasoning.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.6
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• pp.579-587
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• 2008

In collaborative environment, since each agent generally uses different words for the same meaning, there is an obstacle for information sharing. In collaborative product development environment, each agent has different words for representing same product information. As a result, it is hard to share product information in this situation. For solving this problem, semantic-based product information is needed. In this paper, a ontology-based semantic searching system which is able to interact with legacy PDM systems is proposed for product information sharing in collaborative environment Product ontology is represented with OWL format, and the product ontology is processed by Pellet reasoning engine for semantic searching. The system is implemented as a web service which can be integrated with other systems. This paper also introduces the approach with which a PDM system provides a function of semantic search with this search system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.5
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• pp.25-36
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• 2003

Aircraft design pursues integrated design efforts by considering all design elements together. In the integrated design environment, it is crucial for the design data to be consistent, free of errorm, and most recent. Database design process consists of the analysis of the data which shall be stored and managed, the construction of the E-R Diagram, and the mapping of the database table. As a DBMS (DataBase Management System), Oracle 8i is employed to design and construct the database. The database design methodology is devised to apply for the several MDO(Multidisciplinary Design Optimization) techniques like MDF(MultiDisplinary Feasible), IDF(Individual Discipline Feasible), and CO(Collaborative Optimization). The defined process is demonstrated through a couple of design examples, including a simple numerical example and a UCAV(Unmanned Combat Aerial Vehicle) design optimization.

• Journal of the Korea Furniture Society
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• v.20 no.6
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• pp.581-589
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• 2009

Under 'The Design Street' Project, one of the urban environment improvement projects of Seoul, the facilities on the street have been greatly varied in terms of design. In addition, the municipal authority has pushed each district to develop its own identity based on the integrated design of the city. This study was aimed to propose a design which could solve the current problem in street furniture in terms of environmental improvement through an analysis on current street conditions in "Y" District as a part of Seoul Design Street Project. It has attempted to propose 11 street furnitures based on the basic strategy of 'Soft City' which has been promoted by Seoul City in accordance with the Seoul Public Facility Guidelines as 1. Airy Design, 2. Integrated Design, 3. Collaborative Design and 4. Sustainable Design. Among them, for the total design in Seoul six facilities - kiosk, manhole, traffic signal controller, public phone, road sign and waste receptacle were proposed by Seoul City have been accepted. For local differentiation, on the contrary, five items - planter bench, bollard, lifter, bike rack and fence have been newly designed and proposed. Furthermore, it is essential to carry out systematic supervision and continuous management on the detail design and construction of current regional design development projects.

• Journal of Information Technology Applications and Management
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• v.13 no.3
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• pp.89-105
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• 2006

Information revolution shifted the meaning of education from traditional face-to-face education to technology integrated virtual one, namely cyber education. A new way of education, however, has not constituted its methodological standards either performance measurement scheme. The study probes the critical factors that influence students' achievement and satisfaction especially in the cyber education environment. Using hierarchical regression, important factors for students' achievement and satisfaction in the management education environment are presented. The results indicate that students' individual characteristics are relatively less influential for cyber education success. Rather, institutional supports including provision of in-depth interaction among students and with the instructor are more critical. We can infer that cyber education essentially requires three factors: in-depth interactions with instructor collaborative environment among peer students technical support from the institution.