• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.146-149
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• 2003

To control the position, velocity and torque of the ultrasonic motor, a great variety of method are proposed such as the amplitude, phase difference, frequency and so on. In the case of phase difference method, it has some advantages: it can control the direction and velocity of rotation only adjusting the phase difference and it has wide control-band. During the USM driving on adjusting phase difference, its characteristic was transformed by the change of resonance-frequency of stator, which means that the resonance frequency is different according to the phase difference. Consequently, we need to set up the most suitable driving frequency according to each phase difference.

• Journal of Korea Trade
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• v.24 no.5
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• pp.1-17
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• 2020

Purpose - This paper tries to estimate the effects of China's and Japan's free trade agreement (FTA) by panel generalized least squares (GLS). Design/methodology - The GLS model includes the basic gravity theory and Difference in Difference (DD) method to divide FTA conclusion countries and non-FTA conclusion countries with China and Japan. In order to empirically research the difference between Chinese and Japanese FTAs, we use the Difference in Difference in Difference (DDD) method. Findings - This paper finds the distance variable has more influence on Japanese than Chinese trade. The exchange rate indicates that Chinese trade depends on export and Japanese trade has the structure of re-import; shows that the countries that concluded FTAs with China and Japan have more positive trade effects than those that did not; finds the Chinese FTA promotion effects greater than the Japanese FTA because China had pushed ahead with trade policy since joining the WTO in 2001. Originality/value - This study shows that a single country's FTA and trade policies are an important factor concerning not just the promotion of trade but also the issue of trade conflicts.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.4
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• pp.816-826
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• 2017

In this paper, a generalized discretization scheme is proposed that can derive general-order finite difference equations representing the joint probability density function of dynamic response of stochastic systems. The various order of finite difference equations are applied to solutions of the Fokker-Planck-Kolmogorov (FPK) equation. The finite difference equations derived by the proposed method can greatly increase accuracy even at the tail parts of the probability density function, giving accurate reliability estimations. Compared with exact solutions and finite element solutions, the generalized finite difference method showed increasing accuracy as the order increases. With the proposed method, it is allowed to use different orders and types (i.e. forward, central or backward) of discretization in the finite difference method to solve FPK and other partial differential equations in various engineering fields having requirements of accuracy or specific boundary conditions.

• Cross-Cultural Studies
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• v.37
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• pp.383-400
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• 2014

Synonym means that the conceptual meaning of the word is the same or similar while other meanings or function of language difference may exist. That is two or more identified names correspond with one sense and have the words with minor difference. Words with synonym relation are a set of same meaning but conceptual area or emotional color, language function can be identified. Therefore, the core research of synonym is the difference analysis and in general difference analysis is progress in the three aspects of Meaning, Pragmatic, and Semantic. However, the difference analysis is the most important. In this paper, the set of meaning item of synonym word 'Attack' is 'zheng', 'fa', 'tao', 'qin', 'xi'. We compare the meaning of five verbs and analyze the difference and characteristics.

• Journal of Sasang Constitutional Medicine
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• v.14 no.2
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• pp.45-57
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• 2002

1. Purpose and Methode of study This study is that How to connect the characteristics of Sasang constitionion with Aptitude Test. To know the characteristics of each individual in modern times Generally, Psychological Aptitude Test is used. So, According to Sasang constitional groups classified with QSCC II, KIPAT occupation aptitude test ( total 55) and KAT-A aptitude test(total 260) was used. 2. Result of study 1) KIPAT occupation aptitude test rest of Sasang constitional groups Taeumin Group appeared high than another Group in investigative occupation and there is the significant difference between Taeumin Group and Soeumin Group Taeumin Group appeared high than another Group in technological occupation and there is the significant difference between Taeumin Group and Soyangin Group Taeumin Group appeared high than another Group in control aptitude and there is the significant difference between Taeumin Group and Soeumin Group Soyangin Group appeared high than another Group in instigation aptitude and progressive aptitude and there is the significant difference between Soyangin Group and Soeumin Group Soeumin Group appeared high than another Group in utility aptitude and there is the significant difference between Soeumin Group and Taeumin Group, between Soeumin Group and Soyangin Group. Soyangin Group appeared high than another Group in guilty conscience and there is the significant difference between Soyangin Group and Taeuwun Group. Soeumin Group appeared high than another Group in independence aptitude and there is the significant difference between Soeumin Group and Taeumin Group Taeumin Group appeared high than another Group in calculation ability and there is the significant difference between Taeunun Group and Soeumin Group 2) KAT-A aptitude test result of Sasang constitional groups Soyangin Group appeared high than another Group in vacabulary ability and there is the significant difference between Soyangin Group and Taeumin Group. When classified male and female, in the case of male, It showed that Soyangin Group is lower than Other Group in vacabulary ability and there is the significant difference between Soyangin Group and Taeumin Group , between Soyangin Group and Soeumin Group but there is no significant difference in the case of female.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.3
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• pp.349-354
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• 2007

To generate the template of a detected object and to track the overlapped object and the object covered by other objects correctly are important research problems in visual surveillance. The frame difference is not capable of generating the template of slowly moving object. To get around the drawback of the conventional frame difference, we propose a new algorithm for generating a template using adaptive 3-frame difference.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2254-2255
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• 2008

Thermoforming is one of the most versatile and economical process to produce polymer products. The drawback of thermoforming is difficult to control thickness of final products. Temperature distribution affects the thickness distribution of final products, but temperature difference between surface and center of sheet is difficult to decrease because of low thermal conductivity of ABS material. In order to decrease temperature difference between surface and center, heating profile must be expressed as exponential function form. In this study, Finite Difference Method was used to find out the coefficients of optimal heating profiles. Through investigation, the optimal results using Finite Difference Method show that temperature difference between surface and center of sheet can be remarkably minimized with satisfying Temperature of Forming Window.

• Communications of the Korean Mathematical Society
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• v.12 no.4
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• pp.975-984
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• 1997

In the Finsler space with an $(\alpha, \beta)$-metric, we can consider the difference tensors of the Finsler connection. The properties of the conformal transformation of these difference tensors are investigated in the present paper. Some conformal invariant tensors are formed in the Finsler space with an $(\alpha, \beta)$-metric related with the difference tensors.

• Bulletin of the Korean Mathematical Society
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• v.55 no.1
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• pp.297-310
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• 2018

In this paper, a nonlinear high-order difference scheme is proposed to solve the Extended-Fisher-Kolmogorov equation. The existence, uniqueness of difference solution and priori estimates are obtained. Furthermore, the convergence of the difference scheme is proved by utilizing the energy method to be of fourth-order in space and second-order in time in the discrete $L^{\infty}-norm$. Some numerical examples are given in order to validate the theoretical results.

• Bulletin of the Korean Mathematical Society
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• v.35 no.3
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• pp.473-484
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• 1998

We consider a finite difference approximation to a singular boundary value problem arising in the study of a nonlinear circular membrane under normal pressure. It is proved that the rate of convergence is $O(h^2)$. To obtain the solution of the finite difference equation, an iterative scheme converging monotonically to the solution of the finite difference equation is introduced. And the numerical experiment of this method is given.