• Journal of Institute of Control, Robotics and Systems
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• v.14 no.2
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• pp.168-177
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• 2008

Path finding is a key element in the navigation of a mobile robot. To find a path, robot should know their position exactly, since the position error exposes a robot to many dangerous conditions. It could make a robot move to a wrong direction so that it may have damage by collision by the surrounding obstacles. We propose a method obtaining an accurate robot position. The localization of a mobile robot in its working environment performs by using a vision system and Virtual Reality Modeling Language(VRML). The robot identifies landmarks located in the environment. An image processing and neural network pattern matching techniques have been applied to find location of the robot. After the self-positioning procedure, the 2-D scene of the vision is overlaid onto a VRML scene. This paper describes how to realize the self-positioning, and shows the overlay between the 2-D and VRML scenes. The suggested method defines a robot's path successfully. An experiment using the suggested algorithm apply to a mobile robot has been performed and the result shows a good path tracking.

• Journal of Information Technology Applications and Management
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• v.21 no.3
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• pp.135-156
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• 2014

The Online business model for purchasing agent service is getting more popular. However, consumers perceive more risk when buying products from foreign online purchasing agents (FOPA) than from common online sellers (COS). This study focuses on finding out how consumers manage risk when they perceive risk and what different risk-reliever strategies they use when buying from high-risk FOPA and low-risk COS. This study has proved the following two. First, when consumers perceive risk at online purchasing, they tend to select risk-reliever strategies, such as the use of communication media, online assurance mark, seller's record, and secure payment to mitigate risk. With the application of those risk-reliever strategies, they built trust with the seller. Second, risk-perception of FOPA influences usage of communication media and check of online assurance mark more strongly than that of COS. On the contrary, risk-perception of COS influences the check of seller record more strongly than that of FOPA. This study helps to explain why FOPA is proliferating, despite its inherent high risk due to the fact that buyers and sellers are separated in time and space and that buyers and sellers have different social and cultural backgrounds. This study also helps managers of E-commerce to relieve consumer's risk-perception and to build trust.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.2
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• pp.91-95
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• 2008

The large AC generator fault may lead to large impacts or perturbations in power system. The generator protection control systems in Korea have been imported and operated through a turn-key from overseas entirely. Therefore a study of the generator protection field has in urgent need for a stable operation of the imported goods. In present, the algorithm using the current ratio differential relaying based DFT for stator winding protection or a fault detection had been applied that of internal fault protection of a generator. the DFT used for the analysis of transient state signal conventionally had defects losing a time information in the course of transforming a target signal to frequency domain. In this paper, the discrete wavelet transform (DWT) was applied a fault detection of the generator being superior to a transient state signal analysis and being easy to real time realization. The fault signals after executing a terminal fault modeling collect using a MATLAB package, and calculate the wavelet coefficients through the process of a muiti-level decomposition (MLD). The proposed algorithm for a fault detection using the Daubechies WT (wavelet transform) was executed with a C language and the commend line function for the real time realization after analyzing MATLAB's graphical interface. The advanced technique had improved faster a speed of fault discrimination than a conventional DFR based on DFT.

• The KIPS Transactions:PartD
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• v.9D no.1
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• pp.65-74
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• 2002

This paper focuses components interactions which is important factor in designing software components. We classified several types of interaction between components and suggested appropriate graphical notation to extend UML and design process with extended method. Suggested notation and process was verified by practical experiment which is performed in travel agent component application. Representing interaction between components is not same to representing association between classes. UML in current version needs to be extended for representing this kind of components interaction. This research covers UML extension for components interaction and experiment for showing effectiveness.

• Fashion & Textile Research Journal
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• v.3 no.4
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• pp.313-322
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• 2001

This study was designed to investigate actual conditions(the types and the personal physical job related factors) of fashion model in Korea. Survey was done through questionnaire data, 194 fashion models were involved survey. The data were analyzed by using frequency, cluster analysis. The results of this study were as follows : 1) The largest sample were as follows (about personal physical related factors) : unmarried, college graduate and undergraduate, resident in the Seoul, 2-24 yrs female with 175-177 cm, 52-54 kg, B-W-H (33-24-35 inch). 2) The largest sample (about job related factors) were as follows: getting private educational institution, 1-2 yrs job experience, B grade, less than 600,000 won for salaries, 100,000-190,000 won at a stage, 5-6 yrs duration of model work, inexperience in the international fashion stage, take up a foreign language, fashion magazine for fashion source, image and look of individuality for a necessary condition. The motive for job was the concern in the job. Problems with a guarantee were pointed out for the betterment working conditions. 3) The types of fashion model were classified into 4 types : the type of lack of professionalism, the type of show off one's talents, the type of dissatisfaction with working condition, the type of maturity of professionalism.

• Ocean Systems Engineering
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• v.6 no.1
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• pp.99-115
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• 2016

In meeting the technical needs for deepwater conditions and overcoming the shortfalls of single-layer pipes for deepwater applications, pipe-in-pipe (PIP) systems have been developed. While, for PIP pipelines directly laid on the seabed or with partial embedment, one of the primary service risks is lateral buckling. The critical axial force is a key factor governing the global lateral buckling response that has been paid much more attention. It is influenced by global imperfections, submerged weight, stiffness, pipe-soil interaction characteristics, et al. In this study, Finite Element Models for imperfect PIP systems are established on the basis of 3D beam element and tube-to-tube element in Abaqus. A parameter study was conducted to investigate the effects of these parameters on the critical axial force and post-buckling forms. These parameters include structural parameters such as imperfections, clearance, and bulkhead spacing, pipe/soil interaction parameter, for instance, axial and lateral friction properties between pipeline and seabed, and load parameter submerged weight. Python as a programming language is been used to realize parametric modeling in Abaqus. Some conclusions are obtained which can provide a guide for the design of PIP pipelines.

• Korean Journal of Child Studies
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• v.26 no.4
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• pp.263-278
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• 2005

The purpose of this study was to develop a social skills training program for rejected young children and to investigate the effects of the program. The developed program used several kinds of interaction methods such as instruction, modeling, rehearsal, feedback, and positive reinforcement. The contents of the program are consisted of role-play, art, language activities, and games. The experimental group with a sample of 9 four-year-old children was those children rejected by peers. There were the other 9 children assigned to the control group. The experimental group received the social skills training program for 50-60 minutes per day twice a week during 12 sessions, and the control group received no treatment. And 9 popular children also joined the program from ninth to eleventh sessions. As compared to the control group, children in the experimental group showed a significant increase in peer acceptance and social skills after they participated in the program.

• Korean Journal of Computational Design and Engineering
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• v.7 no.2
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• pp.110-120
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• 2002

This paper presents the method that allows easy and rapid integration of legacy resources within the company and between departments. The proposed system can easily construct a distributed environment for collaborative design between departments in the companies. It supports knowledge-based integration system, which allows designers to develop product with deep knowledge about product design. For the purpose, DOME (Distributed Object-based Modeling Environment)-which has been developed through various studies-was used in this paper. To overcome its problems and insufficiency, the Web-Integrator is proposed. The Web-Integrator is very suitable for an Internet environment because it uses HTTP (Hyper Text Transfer Protocol) and XML (extensible Markup Language) as its main communication method. By supporting the remote object access via URL (Uniform Resource Locator), the implementation of the integrated system makes the Web-Integrator systematic and intuitive. All the functions and resources provided by DOME could be used with the interface that enables bi-directional communication with the DOME system. Web-Integrator provides full web-based environments for the general designers, who do not have a full design knowledge and experience, and the proposed system allows design operations to happen at any place and anytime. Also it provides XML-RPC(Remote Procedure Call) based web service framework, which allows other systems to use easily the service that the DOME system supplies regardless the location and the platform.

• Nuclear Engineering and Technology
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• v.40 no.5
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• pp.365-374
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• 2008

Dependability-critical systems, such as digital instrumentation and control systems in nuclear power plants, necessitate engineering techniques and tools to provide assurances of their safety and reliability. Determining system reliability at the architectural design phase is important since it may guide design decisions and provide crucial information for trade-off analysis and estimating system cost. Despite this, reliability and system engineering remain separate disciplines and engineering processes by which the dependability analysis results may not represent the designed system. In this article we provide an overview and application of our approach to build architecture-based, dynamic system models for dependability-critical systems and then automatically generate dynamic fault trees (DFT) for comprehensive, tool-supported reliability analysis. Specifically, we use the Architectural Analysis and Design Language (AADL) to model the structural, behavioral and failure aspects of the system in a composite architecture model. From the AADL model, we seek to derive the DFT(s) and use Galileo's automated reliability analyses to estimate system reliability. This approach alleviates the dependability engineering - systems engineering knowledge expertise gap, integrates the dependability and system engineering design and development processes and enables a more formal, automated and consistent DFT construction. We illustrate this work using an example based on a dynamic digital feed-water control system for a nuclear reactor.

• Industrial Engineering and Management Systems
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• v.11 no.3
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• pp.255-265
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• 2012

Environments surrounding production sites have changed greatly in recent years. Accommodating environmental changes calls for the design and development of information systems that center on production lines. There is a need for a training program that teaches learners to understand the particulars of an operation and apply that knowledge to an information system. In this research, we used material requirements planning (MRP) as the subject for which basic skills are to be taught and developed an MRP exercise-based training program. The program is designed for 13 lectures of 90 minutes each, and it consists of MRP exercises, modeling methods to represent them, the use of a programming language for system development, and finally, evaluation of the exercises. Lecture materials are described in 505 lecture slides using Microsoft PowerPoint to allow visualization of topics through graphs and models. The developed training program was then delivered to 86 college students, and its results were measured through quizzes to verify educational effectiveness.