• Journal of the Korean Society for Railway
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• v.8 no.5
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• pp.490-494
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• 2005

The geometric parameters between wheel and rail change wheel/rail contact geometry characteristics, and this influence dynamic behavior of rolling stock. So, the selections of optimum geometric parameters between wheel and rail is important for planning of railway system. In this study, we have analyzed the influence of geometric parameters like wheel flange-back distance, gage, and rail inclination on the equivalent conicity relating to dynamic behavior. The analyses show the following results. The widening of wheel flange-back distanc, the decrement of gage increase the equivalent conicity and the increment of rail inclination show the sharp change of the equivalent conicity.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03b
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• pp.241-244
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• 1999

A series of parametric study was performed for the investigation of the influence of several analysis parameters to the solution behavior in the elasti-plastic-static analysis of sheet metal forming. The parameters taken into the consideration in the present study are finite element mesh distribution and numerical integration scheme, The elstic-plastic-static analysis was performed for two cases : deflection by a point force bending by a punch Results obtained with different selections of the parameters were compared with each other experimental measurements and analytical solutions.

• The Korean Journal of Applied Statistics
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• v.23 no.2
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• pp.249-261
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• 2010

Long-term forecasting of seasonal time series is critical in many applications such as planning business strategies and resolving possible problems of a business company. Unlike the traditional approach that depends solely on dynamic models, Li and Hinich (2002) introduced a combination of stochastic dynamic modeling with filter bank approach for forecasting seasonal patterns using highly coherent(High-C) waveforms. We modify the filter selection and forecasting procedure on wavelet domain to be more feasible and compare the resulting predictor with one that obtained from the wavelet variance estimation method. An improvement over other seasonal pattern extraction and forecasting methods based on such as wavelet scalogram, Holt-Winters, and seasonal autoregressive integrated moving average(SARIMA) is shown in terms of the prediction error. The performance of the proposed method is illustrated by a simulation study and an application to the real stock price data.

• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.233-241
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• 2003

The rolling schedule procedure has been an important part of the Enterprise Resource Planning (ERP) systems. The performance of production planning in an ERP system depends on the selection of the three parameters in rolling schedule procedure: frozen interval, replanning interval, and planning horizon (forecast window). This research investigated, in a theoretical approach, the combined impact of selections of those three parameters. The proven mathematical theorems provided guidance to re-duction of instability (nervousness) and to seek the optimal balance between stability and responsiveness of ERP systems. Further the theorems are extended to incorporate the cost structure.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.3
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• pp.20-31
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• 2005

The contents of mobile phones are rapidly appended and the structures are being changed substantially. Most of the problems with mobile phones are related with the vibrations and the displacements of PCB boards. In this study, the vibration magnitudes of the boards by impulses on the case are analyzed with the variations of the selected design parameters. The result shows that the extensive suppression of the vibrations are feasible by the proper selection of the design parameters. Also the suggested relationships between the parameter selections and the magnitudes of vibrations can be applied to establish a database for improved stability of the mobile phone structure which is a critical concern considering the short life span of the mobile phone models.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.65-65
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• 2000

For Video on Demand(VoD) servers, a design of an efficient scheduler is important to the support a large number of clients having various playback speeds and receiving rates. In this paper, we propose the scheduling algorithm to handle establishing deadlines and selection using the earliest deadline first. To establish deadlines and selections, the period of the receiving rates for each client is located between the over-max receiving rate and the over-playback rate. To avoid video starvation and the buffer overflow of each client, the proposed algorithm guarantees providing the admission control. Because of establishing deadlines and selection, period of each client receiving is between one over max receiving rate and one over play back rate. Using Virtual Buffer in server, scheduling load is reduced. The efficiency of the proposed algorithm is verified using a Petri Net_Based simulation tool, Exspect.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.532-532
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• 2000

Conventional artificial intelligence systems are not properly responding under dynamically changing environments. To overcome this problem, reactive planning systems implementing new Al principles, called behavior-based Al or emergent computation, have been proposed and confirmed their usefulness. As another alternative, biological information processing systems may provide many feasible ideas to these problems. Immune system, among these systems, plays important roles to maintain its own system against dynamically changing environments. Therefore, immune system would provide a new paradigm suitable for dynamic problem dealing with unknown environments. In this paper, a new approach to behavior-based Al by paying attention to biological immune system is investigated. The feasibility of this method is confirmed by applying to behavior control of an autonomous mobile robot in cluttered environment.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2008.10a
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• pp.94-97
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• 2008

CD Now, Video Recommender, Amazon 등과 같은 현재의 협업 기반 필터링 서비스는 일반적으로 서비스를 요구하는 사용자가 관심을 가진 아이템과 비슷한 속성의 아이템을 추천하고 있다. 하지만 영화와 같은 경우 사용자의 주관적 평가가 배제된-명시적 속성만으로는 아이템의 특징을 표현하는데 한계가 있다. 때문에 이를 이용한 방법은 서비스를 제공하는 데 있어 제한을 가지게 된다. 따라서 본 논문에서는 소셜 네트워크 서비스 사용자가 영화에 대한 자신의 감정을 간단한 선택을 통해 표현함으로써 쉽고 편하게 사용자의 영화 취향을 도출하고 이를 기반한 소셜 네트워크를 형성하는 방법에 대해 논의해 보고자 한다. 이러한 방법을 통해 일반적으로 사용되는 빈도나 인기도 기반의 추천이 아닌 실제 사용자와 유사한 취향과 특성을 가지는 사용자들은 연결해줌으로써 보다 사용자에 특화된 추천을 가능하게 할 것이다.

• Culinary science and hospitality research
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• v.14 no.2
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• pp.18-29
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• 2008

This study is to investigate the cognition and usage of traditional wedding food in Seoul & Gyeonggi area. It provides the basic suggestions for developing the best wedding culture, upholding the great wedding tradition. People usually prepared traditional wedding food only because they had to do since they thought it was a formal way to do it at a wedding ceremony. However, there should be more important things to be considered. Firstly, to understand the real meaning of traditional wedding food, we need to inform its meaning by starting campaigns on wedding culture or making booklets of traditional wedding food. Secondly, to prepare the right selections of traditional food, we need to simplify traditional wedding food and consider the modern sense of the products. Thirdly, to improve traditional wedding food, we need to develop diverse menu. By doing it, we can efficiently reduce the cost of wedding food.

• Journal of Communications and Networks
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• v.4 no.4
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• pp.344-350
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• 2002

This work summarizes the current state of the art in software radio for 4G systems. Specifically, this work demonstrates that classic radio structures, e.g., heterodyne reception, homodyne reception, and their improved implementations, are inadequate selections for multi-mode reception. This opens the door to software defined radio, a novel reception architecture which promises ease in multi-band, multi-protocol design. The work presents the many advantages of such an architecture, including flexibility, reduced cost via component reduction, and improved reliability via, e.g., the elimination of environmental instability. The work also explains the limitations that currently curtail the widespread use of SDR, including issues surrounding A/D converters, management of software and power, and clock generation. This provides direction for future research to enable the broad applicability of SDR in 4G cellular and beyond.