• Journal of the Korean Society for Precision Engineering
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• v.12 no.6
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• pp.145-151
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• 1995

The first-order Taylor series expansion can be evaluated analytically from the formulated symbolic nonlinear dynamic equations. A closed-form linear dynamic euation is derived about a nominal trajectory. The state space representation of the linearized dynamics can be derived easily from the closed-form linear dynamic equations. But manual symbolic expansion of dynamic equations and linearization is tedious, time-consuming and error-prone. So it is desirable to manipulate the procedures using a computer. In this paper, the analytic linearization is performed using the symbolic language MATHEMATICA. Two examples are given to illustrate the approach anbd to compare nonlinear model with linear model.

• Journal of the Chungcheong Mathematical Society
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• v.26 no.4
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• pp.787-791
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• 2013

In this paper we present one factor model of commodity prices with a single jump regime-switching process. And we derive an analytic formula for pricing futures contracts when the parameters of commoditiy process have governed by a Markov regime-switching process.

• Proceedings of the Korea Concrete Institute Conference
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• 1990.04a
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• pp.96-101
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• 1990

본 논문은 반복하중에 의한 콘크리트 부재거동에 대한 수학적인 해석방법에 관한 것으로서 철근콘크리트 부재의 Hysteretic 거동의 주요한 현상들인 강성저하, 강도저하 그리고 전단영향 등의 수치해석 Model을 소개하였다. 그리고 본 해석 Model의 정확성 및 사용성 등을 평가하기 위하여 R.C.콘크리트 부재에 대한 수치 해석 예제를 제시하였다.

• Journal of the Korean Data and Information Science Society
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• v.10 no.1
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• pp.19-27
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• 1999

An orientation-shift model for unit random vectors in $R^3$ is defined. The Euler angles are introduced to parametrize orientation-shifts and their moment estimators are found. Through the analytic perturbation method, the asymptotic distributions of the estimators are obtained.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.10
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• pp.867-873
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• 2001

The purpose of this study is to find analytic solution of determining the optimal capacity (lot-size) of multiproduct acyclic multistage production and inventory system to meet the finished product demand under the constraint of finite intermediate storage. Intermediate storage is a practical way to mitigate the material flow imbalance through the line of supply and demand chain. However, the cost of constructing and operating storage facilities is becoming substantial because of increasing land value, environmental and safety concern. Therefore, reasonable decision-making about the capacity of processes and storage units is an important subject for industries. The industrial solution for this subject is to use the classical economic lot sizing method, EOQ/EPQ(Economic Order Quantity/Economic Production Quantity) model, incorporated with practical experience. But EOQ/EPQ model is not suitable for the chemical plant design with highly interlinked processes and storage units because it is developed based on single product and single stage. This study overcomes the limitation of the classical lot sizing method. The superstructure of the plant consists of the network of serially and/or parallelly interlinked non-continuous processes and storage units. The processes transform a set of feedstock materials into another set of products with constant conversion factors. A novel production and inventory analysis method, PSW(Periodic Square Wave) model, is applied to describe the detail material flows among equipments. The objective function of this study is minimizing the total cost composed of setup and inventory holding cost. The advantage of PSW model comes from the fact that the model provides a set of simple analytic solutions in spite of realistic description of the material flows between processes and storage units. the resulting simple analytic solution can greatly enhance the proper and quick investment decision for the preliminary plant design problem confronted with economic situation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.2
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• pp.133-147
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• 2011

This study presents the credit evaluation model for medical venture business which has been growing within the recent decade. We develop the model with two steps. At the first step, the evaluation indexes for each of the financial and non-financial factors of a firm are listed. At the second step, the weight for each index is measured by using the Analytic Hierarchy Process of Saaty(1980). The financial factors consists of 5 upper level indexes and 10 lower level indexes. The upper level indexes of the financial sector are profitability, safety, utilization, growth, and productivity. And the non-financial factors consists of 5 upper level indexes and 17 lower lever indexes. The upper level indexes in this sector are manager's competence, technical capability, marketability, business validity, and reliability. In order to get the empirical results for our model, we conduct the questionnaire survey targeting the credit assessment officers, who are practicing at the financial institutions or the credit guarantee company located within the Wonju Medical Devices Cluster.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.2
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• pp.108-115
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• 2015

Electro-mechanical actuator installed on aircraft consists of a decelerator which magnifies the torque in order to rotate an axis connected with aircraft control surface, a control section which controls the motor assembly through receiving orders from cockpit and a motor assembly which rotates the decelerator. Electro-mechanical actuator controls aircraft altitude, position, landing, takeoff, etc. It is an important part of a aircraft. Aircraft maneuvering causes vibrations to electro-mechanical actuator. Vibrations may result in structural fatigue. For that reason, it is necessary to analyze the system structural safety. In order to analyze the system structural safety. It is needed reasonable finite element model and structural response stress closed to real value. In this paper, analytic model is derived by using the simplified finite element model, and damping ratio which is closely related to response stress is derived by using modal test. So, we developed analytic model in less than 10 % error rate, compared with modal test. Vibration response stress close to real value was estimated from analytic model modified with modal experimental damping ratio. Estimation method for damping ratio with empirical formula was suggested partly. Finally, It was proved that electro-mechanical actuator had reasonable structure margin of safety at environmental random $3{\sigma}$ stress during life cycle.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.1069-1074
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• 2009

Public displays are evolving from a one-way display to an interactive medium which contains dynamic transition of various media. This study focuses on the interaction between human and digital technology-based art on public display from a HCI point of view, while several viewpoints exist on interactive public displays. We present a new interaction model which suggests different interactions depending on the viewer's distance and direction so that public display could offer rich media experiences. We have also and built an installation art to examine the efficacy of our interaction model. As such, we introduced two methodologies from HCI to derive our final interaction model. First of all, we analyze previous distance-dependent interaction models for public display in terms of context analytic approach, and propose an effective model for human-digital art interaction. Second, we introduce the concept of aura in HCI as user analytic approach to redefine interaction depending on the viewer's direction of attention. Thus, this study aims to suggest a new interaction model based on the previous two analyses to improve interaction between human and digital technology-based art on public display.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2827-2830
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• 2003

Tele manipulator is distingushed from industrial robot by iterating same specified work. Manipulator operator is included in control loop for controlling the telemanipulator because he decide directly during the work and order controllabily reducing the modelling error of telemanipulator which depend on the PID controller. But position-force control method of bidirectional control impose unsafety of vibiration and Analytic Hierachy Method can stabilize for reducing nonlinear modelling error by expert operator because of transformation empirical control rule to linear model.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.16 no.27
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• pp.113-119
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• 1993

The purpose of this study is to develop a analytic procedure of the alternatives for the FMS that consist of high-priced facilities. A procedure to analysis the alternatives are as follows. Stage one is procedure to appraise investment alternatives of FMS and devide factors into strategic, analytic, economic viewpoint and draw upon decision making matrix through normalization Stage two is appraise to normalized alternatives using TOPSIS model among multiple attributes decision making models.