• Journal of Ocean Engineering and Technology
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• v.19 no.2 s.63
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• pp.29-33
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• 2005

The accuracy of predicting wave transformation in the nearshore is very important to wave hydrodynamics, sediment transport, and design of coastal structures. Numerical experiments are conducted to identify the shoaling and breaking characteristics of a fully nonlinear Boussinesq equation-based model. Simulated shoaling showed good agreement with the Shouto's formula, and the results of the breaking experiment agreed well with experimented data, over several beach profile.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.3
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• pp.233-240
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• 2011

Purpose: To apply a computer assisted navigation system to orthognathic surgery, a simple and efficient measuring algorithm calculation based on affine transformation was designed. A method of improving accuracy and reducing errors in orthognathic surgery by use of an optical tracking camera was studied. Methods: A total of 5 points on one surgical splint were measured and tracked by the Polaris $Vicra^{(R)}$ (Northern Digital Inc Co., Ontario, Canada) optical tracking system in two cases. The first case was to apply the transformation matrix at pre- and postoperative situations, and the second case was to apply an affine transformation only after the postoperative situation. In each situation, the predictive measuring value was changed to the final measuring value via an affine transformation algorithm and the expected coordinates calculated from the model were compared with those of the patient in the operation room. Results: The mean measuring error was $1.027{\pm}0.587$ using the affine transformation at pre- and postoperative situations and the average value after the postoperative situation was $0.928{\pm}0.549$. The farther a coordinate region was from the reference coordinates which constitutes the transform matrixes, the bigger the measuring error was found which was calculated from an affine transformation algorithm. Conclusion: Most difference errors were brought from mainly measuring process and lack of reproducibility, the affine transformation algorithm formula from postoperative measuring values by using of optic tracking system between those of model surgery and those of patient surgery can be selected as minimizing the difference error. To reduce coordinate calculation errors, minimum transformation matrices must be used and reference points which determine an affine transformation must be close to the area where coordinates are measured and calculated, as well as the reference points need to be scattered.

• Physical Therapy Korea
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• v.13 no.3
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• pp.49-56
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• 2006

This study was designed to examine, using Rasch analysis, the rating scale performance of the Korean version of the Berg Balance Scale (BBS). The subjects were 95 elderly people at community dwelling. Subjects (19 men, 76 women) ranged in age from 65 to 91 years. Rasch analysis was then done by means of the Winsteps program to determine the validity and reliability of the Korean version of the BBS evaluation tools for elderly people. The results were as follows: Twenty-one elderly people were excluded for misfit persons. Three items were found to be misfits and the order of item difficulty of the remaining 11 items was arranged. Elderly people BBS ability is indicated by -.94~7.41 logit, and the transformation formula is score=(logit score+.94)/$(.94+7.41){\times}100$. This transformation formula can be applied to Korean elderly people for balance ability. In the order of difficulty of evaluation items, the most difficult item was "Standing on one foot" and the easiest item was "Standing to Sitting". In conclusion, the Korean version of BBS evaluation tool for the elderly people has been proved valid and will be useful in clinical practice and research in Korea.

• Herbal Formula Science
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• v.25 no.4
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• pp.437-447
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• 2017

Objective : Zhang zhi-cong insisted the theory related to the 'Six-meridian qi transformation', and Zhen xiu-yuan inherited that theory understanding six-meridian disease of "Shang-Han-Lun". This emphasizes that the disease of 'three yin and three yang' in "Shang-Han-Lun" is a disease caused by Six-meridian qi transformation, not a lesion of meridian itself. He said, "If you do not know brightly in the 'Tip, Root and Middle qi', you can not read the "Shang-Han-Lun"." Therefore, in this paper, we examine the interpretation of the "Shang-Han-Lun"by using the theory of 'five circuits and six qi'. Method : First, extract sentences related to 'Tip, Root and Middle qi' from the sentences of "Shang-Han-Lun" Second, the sentence is interpreted through the Zhen xiu-yuan's "Sang han lun qian zhu". Third, the meaning of the sentence is examined and summarized. Result : Zhen xiu-yuan proposed a clear and systematic theory that can understand the meaning of Six-meridian in "Shang-Han-Lun", by utilizing the discipline that 'Tip, Root and Middle qi' Conclusion : The change of 'Tip, Root and Middle qi' is a very central theory that explains the properties of 'Yin and Yang' and mutual correspondence among Korean medicine theories. It also provides basic directions for understanding the changing patterns of disease.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.163-164
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• 2019

In this study, we compared the differences between groups in a model that investigates the effect of smartphone users on the intent to use continuously. There are various methodologies for group difference analysis, but in this study, we try to verify the size comparison of regression analysis $R^2$. In order to analyze the difference between groups, we try to prove through hypothesis test whether there is a meaningful difference in the intention of continuous use of Korean and Chinese smartphone users collected through previous research. The results of the analysis are useful as a method to determine whether smartphone users in China and Korea are aware of differences or not. According to this procedure, first, the formula for calculating Z-transformation of Fisher and Z-score test statistic calculation formula were used. However, this methodology is also used in the verification of control effect using correlation coefficient. Also, the theoretical implications are presented based on the analysis results.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.6
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• pp.271-275
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• 2014

A New Single Phase Active Power Filter Controller is proposed using Rotating Synchronous Frame d-q transformation. Instantaneous Active Power is calculated using d-q transformation. Average Value of Instantaneous Active Power is obtained using Low Pass Filter. Because power factor is corrected, source current is in phase with source voltage. Amplitude of source current is calculated using single phase power formula. Reference signal of compensated current of Active power filter is obtained from source current reference signal minus load current. Simulation is performed using hysteresis current controller in proposed new controller. Simulation result shows that because active power filter compensates load current, source current is in phase with source voltage and source current is sinusoidal. And Hilbert transformer is builded using all pass filter.

• Journal of the Korean Society of Hazard Mitigation
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• v.1 no.2 s.2
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• pp.93-101
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• 2001

The objective of this study is to derive a shrinkage correction formula that considers temperature effect and to develop a methodology for the improved prediction of the long-term behavior of the FCM bridges by considering seasonal temperature variations in-situ. Thereby, current formulation were performed by using the actual experimental shrinkage data including seasonal temperature variation. The investigation of the long-term behavior of the FCM bridge was performed on the construction site in order to decide applicability of the shrinkage formula Numerical results by the general method indicates inaccurate values of total strain when considering real strain, whereas the applied method demonstrates a good agreement in the resultant strain. In consequently, the applied method will improve the prediction of the long-term deformation of the FCM Bridges.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.3 no.3
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• pp.163-169
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• 1991

Sixty seven regular wave tests were performed in a wave-current flume to investigate proper-ties of waves breaking on irregular slope profiles. In these tests, 1/10, 1/20 beach slopes were made using angles and plywoods. A little differences were found in such properties as breaker depth and height indices. runup for plane slopes comparing with other laboratory experiments. however. for smaller deepwater wave steepness, measured breaker height and depth data values were smaller than other formulas. On wave runup agreement was good between experiments and Hunt formula. however. measured data values were influenced by number of breaking. Significant differences were found in breaker depth index for plane and barred slopes. Wave height decay after breaking was found to be smaller than Dally et al.'s formula (1984).

• Communications of the Korean Mathematical Society
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• v.9 no.4
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• pp.881-889
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• 1994

Let ($X, \Beta, \mu$) be a measure space with the $\sigma$-algebra $\Beta$ and the probability measure $\mu$. Throughouth this article set equalities and inclusions are understood as being so modulo measure zero sets. A transformation T defined on a probability space X is said to be measure preserving if $\mu(T^{-1}E) = \mu(E)$ for $E \in B$. It is said to be ergodic if $\mu(E) = 0$ or i whenever $T^{-1}E = E$ for $E \in B$. Consider the sequence ${x, Tx, T^2x,...}$ for $x \in X$. One may ask the following questions: What is the relative frequency of the points $T^nx$ which visit the set E\ulcorner Birkhoff Ergodic Theorem states that for an ergodic transformation T the time average $lim_{n \to \infty}(1/N)\sum^{N-1}_{n=0}{f(T^nx)}$ equals for almost every x the space average $(1/\mu(X)) \int_X f(x)d\mu(x)$. In the special case when f is the characteristic function $\chi E$ of a set E and T is ergodic we have the following formula for the frequency of visits of T-iterates to E : $$ lim_{N \to \infty} \frac{$\mid${n : T^n x \in E, 0 \leq n $\mid$}{N} = \mu(E) $$ for almost all $x \in X$ where $$\mid$\cdot$\mid$$ denotes cardinality of a set. For the details, see [8], [10].

• Water for future
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• v.26 no.1
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• pp.71-79
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• 1993

Nonlinear characteristics of air pressure variation and wave transformation of a fixed air-chamber structure are discussed theoretically and experimentally. Two analytical methods(method I and II) based on the perturbation method and Green's formula are employed in order to evaluate nonlinearities by the submerged and semi-submerged air-chamber structure. Moreover, an air compression model is newly developed to estimate the dynamic air pressure in the air-chamber inside the structure, assuming the Boyle-Charles's law with adiabatic process in the air pressure variation. Theoretical values of the method I considering evanescent mode waves at an fictious boundary, are in good agreement with those of method II employing the fictious boundary which is not affected by evanescent mode waves. Both theoretical values are shown to agree well with experimental values.