• Structural Engineering and Mechanics
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• v.26 no.2
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• pp.191-210
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• 2007

The three different approaches (reformulations) of evolution strategies (ESs) have been proposed in the literature as extensions of the technique for solving discrete problems. This study implements an extensive research on application, evaluation and comparison of them in discrete optimum design of steel frames. A unified formulation is first developed to explain these approaches, so that differences and similarities between their inherent search mechanisms can clearly be identified. Two examples from practical design of steel frames are studied next to measure their performances in locating the optimum. Extensive numerical experimentations are performed in both examples to facilitate a statistical analysis of their convergence characteristics. The results obtained are presented in the histograms demonstrating the distribution of the best designs located by each approach. In addition, an average improvement of the best design during the course of evolution is plotted in each case to compare their relative convergence rates.

• Journal of the Korean Institute of Rural Architecture
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• v.6 no.2
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• pp.21-30
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• 2004

The purpose of this study is to consider critically the conceptural meaning and the arch itectural planning-techniques of environment-friendly architecture in Korean contemporary architecture. The related conceptual meaning and design-techniques on environment-friendly architecture are proposed by considering items in relation with adapting to natural environment, human life, historical imagination. These items are adapting technical methods to architectural design in a narrow sense. We have to reconsider its wide application. Through this consideration, this study is proposed a right direction of environment-friendly architecture in the future.

• Structural Engineering and Mechanics
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• v.3 no.5
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• pp.475-495
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• 1995

In the past, physical models have been proposed, in compliance with the concept of the compressive-force path, for the realistic design of various statically determinate structural concrete members. The present work extends these models so as to encompass indeterminate RC structural forms. Pilot tests conducted on continuous beams and fixed-ended portal frames have revealed that designing such members to present-day concepts may lead to brittle types of failure. On the other hand, similar members designed on the basis of the proposed physical models attained very ductile failures. It appears that, unlike current design approaches, the compressive-force path concept is capable of identifying those areas where failure is most likely to be triggered, and ensures better load redistribution, thus improving ductility. The beneficial effect of proper detailing at the point of contraflexure in an indeterminate RC member is to be noted.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.181-186
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• 2002

Laser welding application for car body manufacturing has many advantages in the stiffness and the lightness of vehicle, the productivity of assembly line, and the degree of freedom in design. This presentation will express the innovation of car body manufacturing including parameter optimization, process modeling, and system integration. In this application the investment for systems was cut down dramatically by real time switching over the laser path between two welding stations. Points of technical discussion are as follows: optimization of parameters such as laser power, robot speed and trajectory, compact and useful design of jig & fixture to assure welding quality for 3 sheet-layer zinc-coated steel, system integration between 4kW Nd:YAG laser device and the other systems, on-line real time welding quality monitoring system, perfect safety standards for high power laser, minimization of consumption costs such as arc lamp, protective glass for optic, etc. Laser welding has found a place on Hyundai's production plant in conjunction with the startup of mass production of new sports car, and this production system is the result of a collaboration of its engineers. Outer side sheets are joined to inner side sheets by 122 stitch welds totally. And the length is about 2.4meter.

• Korean Journal of Remote Sensing
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• v.32 no.3
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• pp.287-305
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• 2016

Over the past half century, satellites have continuously expanded their roles in remote sensing applications. As the number of satellites to be launched are expected to continuously increase in coming years, the research on satellite payloads will be in high demands. Earth Observation (EO) satellites are nowadays widely utilized for various purposes. Especially, Agriculture and forestry applications are considered as their major application areas. Since about 85% of domestic land cover is classified as forest or cropland areas, it would be reasonable to suggest that the demand for these satellites should be of high priority. In this paper, a comprehensive analysis is performed on the technical specifications of satellite payloads that may be applicable to agricultural applications. We attempted to build a solid database on payload specifications by collecting relevant information available from various related institutes and academic research works. A number of experts involved in national agricultural research and satellite development programs have been invited to investigate required payload design. Based on the current technology development status and future plan, multiple options for future satellite payload designs have been suggested bearing in mind that the results may be applicable to the future agriculture and forestry satellite payload design. The proposed payload specifications are analyzed in depth through satellite operation simulations under the mission of observing the national agriculture areas. The proposed design scheme and simulation results may be used as technical references to satellite payload design for future space missions.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.2
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• pp.37-45
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• 1999

CORBA IDL and RMI, the representative of distributed object model, support different approaches for distributed computing environments. CORBA approach does not support the application generated by RMI, even though it supports multiple programming languages. Object translation system between RMI to CORBA is designed and implemented for interoperability of distributed objects on the two different distributed programming environments. Suggested system is considered binding, inheritance, polymorphism, object passing, and callback which are key properties on the distributed objects. To validate the usefulness of the proposed system, we adopt a model for distrubuted objects and implement it as an application on the RMI environment. And, we translated it to an application on the CORBA environment. We observed the performance of translated application in the respect of inheritance, object passing, polymorphism across the machine boundary. Experiments showed that performance of distributed objects, those generated by translation system and those implemented on the CORBA environment, is equivalent.

• International Journal of Naval Architecture and Ocean Engineering
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• v.3 no.1
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• pp.72-79
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• 2011

Typical results obtained by a newly developed, nonlinear time domain hybrid method for simulating large amplitude motions of ships advancing with constant forward speed in waves are presented. The method is hybrid in the way of combining a time-domain transient Green function method and a Rankine source method. The present approach employs a simple double integration algorithm with respect to time to simulate the free-surface boundary condition. During the simulation, the diffraction and radiation forces are computed by pressure integration over the mean wetted surface, whereas the incident wave and hydrostatic restoring forces/moments are calculated on the instantaneously wetted surface of the hull. Typical numerical results of application of the method to the seakeeping performance of a standard containership, namely the ITTC S175, are herein presented. Comparisons have been made between the results from the present method, the frequency domain 3D panel method (NEWDRIFT) of NTUA-SDL and available experimental data and good agreement has been observed for all studied cases between the results of the present method and comparable other data.

• Computers and Concrete
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• v.21 no.6
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• pp.637-647
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• 2018

Numerical approach using finite element method has been used to evaluate the behaviour of reinforced concrete frame structure subjected to fire. The structure is previously designed in accordance with Eurocode standards for the design of structures for earthquake resistance, for the ductility class M. Thermal and structural response are obtained using a commercially available software ANSYS. Temperature-dependent nonlinear thermal and mechanical properties are adopted according to Eurocode standards, with the application of constitutive model for the triaxial behaviour of concrete with a smeared crack approach. Discrete modelling of concrete and reinforcement has enabled monitoring of the behaviour at a global, as well as at a local level, providing information on the level of damage occurring during fire. Critical regions in frame structures are identified and assessed, based on temperatures, displacements, variations of internal forces magnitudes and achieved plastic deformations of main reinforcement bars. Parametric analyses are conducted for different fire scenarios and different types of concrete aggregate to determine their effect on global deformations of frame structures. According to analyses results, the three-dimensional finite element model can be used to evaluate the insulation and mechanical resistance criteria of reinforced concrete frame structures subjected to nominal fire curves.

• Korean Institute of Interior Design Journal
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• v.13 no.2
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• pp.29-37
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• 2004

This study analyze the architectural space in the aspect of the 'Raumplan' and 'Plan Libre'. These concepts based on the 'Raumplan versus Plan Libre' exhibition in Delft University, Netherlands. It is generally agreed that the concept of 'Plan Libre' in connection with Le Corbusie architecture and 'Raumplan' related to Adolf Loos's works. that exhibition contents was focused an extent of modem architecture. But, These concepts continually influence contemporary architecture and offer diverse vision in architecture. Therefore, this study focused on the analysis that look for common element in the space through the case study and space element connection in change of the values, technical growth. This Paper reveals that Adolf Loos's Raumplan is similar to Louis I. Kahn's 'Room' concept and Ando Tadao's centrifugal space composition method In the dwelling architecture. And the concept 'Plan Libre': non-definitive formal system and the elements : column, free form screening wall is revived as formal application of 3 dimension composition in architecture. and transfer lots, void, and linear space in Rem Koolhaas's urban design projects. These aspects is so called topology. This topological concept is an attempt in view of the space connection state rather than formative viewpoint.

• Journal of the Korean Society of Systems Engineering
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• v.2 no.2
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• pp.11-20
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• 2006

For systematic and effective achievement of Military R&D(Research and Development) processes and activities, information system which supports the concept of Systems Engineering is necessary. WISEMAN(Weapon System Information Integration for System Engineering and Management) is an information integration system, which can provide various kinds of interrelated application functions and assist the collaboration and concurrent engineering activities for weapon system R&D processes and activities. WISEMAN can manage the design information and configuration data of the target development products. It takes charge of the processes and histories about the product data, makes to share all the design information, and provides important application functions for R&D processes such as requirement management, product structure management, parts Management, documents and CAD drawing management, design change management, TDP(Technical Data Package) management etc., and in conjunction with these functions WISEMAN controls various effectivities of system configurations based on baselines and model information. WISEMAN has been used by ADD and Rotem Co. since developed.