• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.331-334
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• 1993

It is a standard problem that designs a controller to minimize the $H_{\infty}$-norm of a given plant. By reducing a standard problem to a model-matching problem, we can obtain all the parameters which consist of a controller. After presenting a practical model and applying it to a tracking model, we design an $H_{\infty}$ controller and an LQ controller to concrete that $H_{\infty}$ control theory is far more robust than LQ control theory. And we show the advantage of an $H_{\infty}$ controller by obtaining a desired Bode diagram and comparing it with that of an LQ controller.

• Korean Journal of Optics and Photonics
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• v.11 no.3
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• pp.187-192
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• 2000

We analyze the parametric amplification by the nonlinear characteristics in a semiconductor laser using a perturbation theory and discuss its result. The parametric gain increases with increase of the pump modulation current. It is due to shift of the resonance frequency as the pump modulation current increases. However, it decreases with increase of the bias current and damping constant. Also, it needs phase matching between the pump modulation current and signal modulation current to maximize the parametric gain. The gain decreases for a large signal modulation current due to the saturation of the amplified power. power.

• Asia Marketing Journal
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• v.22 no.1
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• pp.1-26
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• 2020

Firms employing hierarchical loyalty programs (HLPs) periodically demote customers from higher to lower status level to divest from unprofitable customers and boost profitability. However, existing literature lacks objective evidence on how customer demotion affects demoted customers' future purchase behaviors and ultimately profitability for the firm. Moreover, customers in the HLP's higher position may respond to customer demotion differently from those in the HLP's lower position. Drawing upon emotions and equity theories, this study quantifies how the profits that customers contribute to the firm change after customer demotion, and compares demoted customers' behavioral reactions from top-tier with those from bottom-tier based on customers' actual behavior data from a major retail bank in South Korea. The findings show that withdrawing customer status actually deteriorates customer profitability, and customers with top-tier status decrease their profitability more dramatically than those with bottom-tier status after demotion. The results contribute to previous literature on customer demotion and relationship marketing, and provide specific guidelines into how firms should design and implement customer demotion in HLPs.

• Journal of Haehwa Medicine
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• v.15 no.2
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• pp.39-52
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• 2006

We came to the conclusion as follows from the research about pulse diagnostic technique (脈診) out of "Nan Jinghoeju jeonjung" (難經滙注箋正). 1. "Nan Jing" is practical medical book for clinician and holds different opinions about three portions and nine takings(三部九候脈法) from Huang Di Nei Jing's Taking the pulse of Bu Jung Chim Chon Kwan Chuk((浮中沈 寸關尺) is a quite creative means which has been a important role to future generation. 2. We pointed the differences between western medical science and traditional medical science. And can explain the pulse in western medicine divided from twelve channels of Oriental Medicine. We can explain special connection between heart and lungs using the theory of systemic & pulmonary circulation in western medicine. And this can be a basement of Lung controls every pulse theory in oriental medicine. 3. We have negative assertion about viewing the human body using theory of Yin and Yang-Five Elements. And have poor opinion of explaining about the matching internal organs to Chon Kwan Chuk using the theory of Yin and Yang-Five Elements. 4. We pointed out the mistake that Porak & Sang hwa act for heart. We took pulses considering heart is a real actual internal organ as others. 5. We denied the theory of Man's Chuk pulse is always weak(男子尺脈恒弱) & Woman's Chuk pulse is always strong(女子尺脈恒盛). The physical form of man and woman is not different from each other considering their inheritances from forefather & same shape of organs. So, we cannot insist on the theory.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.5
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• pp.790-795
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• 2010

Sasang Constitution Medicine(SCM)'s researches have been developed in many ways, especially Herbal medicine prescriptions and diagnosis. But there are no acceptable acupuncture theory for the Sasang Constitution. So We have tried to find the way for identifying each Sasang Constitution's acupuncture point on more reasonable methods. We studied that SCM acupuncture based on collecting Books of "Shanghanlun(傷寒論)", or Six-meridian pattern identification's acupuncture prescription. Selected books are "The Acupuncture and Moxibustion(침구학)", "Zhonghua Zhenjiuxue(中華鍼灸學)", "Zhenjiuxinchuan(鍼灸心傳)", "Shanghanlun Zhenjiupeixuexuanzhu(傷寒論鍼灸配穴選注)". So-eumin uses Conception Vessel's acupuncture points most frequently. And So-yangin and Tae-eumin use Bladder meridian and Stomach meridian's acupuncture points most. Moxibustion is used many times for So-eumin, especially at three Yin-Symptoms(三陰病). Orders for using frequencies of three Sasang constitutions' acupuncture points are: So-eumin uses ST36 CV12 CV4 most, So-yangin uses PC6 ST36 LI4 most, Tae-eumin uses ST36 LU7 CV12 most. Acupuncture for Sasang constitutions has been developed for many ways, but there are no generally acceptable theory. So we need to hold a committee for SCM and acupuncture specialist to establish acceptable and reasonable SCM acupuncture theory.

• Journal of the Korea Computer Industry Society
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• v.10 no.5
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• pp.187-192
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• 2009

In this paper, we proposed an algorithm for personal identification of dorsal surface pattern of hand vein pattern using graph theory. Using dense ranee data images of the hand vein pattern, we used matching algorithm within the frame work of graph theory for the determination of the desired correspondence. Through preprocessing, the captured images are more sharp, clear and thinning. After thinning, the images are normalized and make graph with node and edge set. This normalized graph can make adjacent matrix. Each adjacent matrix from individual vein pattern are different. From examining the performance of individual vein patterns, we can approach performances well kind biometric technique.

• The Journal of Korean Medical History
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• v.21 no.2
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• pp.149-158
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• 2008

Yun Gil-Young, who is also known by his pen name, Hyun-Gok, was an Oriental Medicines practitioner since 1943 and was a leader of the society of Oriental medicines in Korea through his advocation as a professor of the University of Eastern Medicines and the College of Oriental Medicines, Kyunghee University. His writings can be first found in the magazine called Eastern Medicines in 1955. His writings, titled 'The Theory of the Biology of Oriental Medicines and its Treatment', elaborates the details of the study of the biology of Oriental Medicines and its directions. His argument of the directions in which to study Biology of Oriental Medicines further are: do not study Biology of Oriental Medicines without understanding its methodology but with knowledge on the biology of western medicines; do not put up with the abstract theory of Yin and Yang and the Five Phases leaving the purpose and the object of the study, just because they are the basic theory of the Biology of Oriental Medicines; do neither matching oriental medicines and western medicines one by one forcibly nor shun the knowledge of western medicines of the modern scientific methodes and try to keep to old customs.

• Journal of Korean Medical classics
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• v.34 no.3
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• pp.85-100
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• 2021

Objectives : The OunyukgiUihakbogam authored by Cho, Wonhee, despite its relevance to application of the five circuit theory today, has been under-researched. Methods : Contents on the unique treatment approach through the 'visiting circuit and visiting qi(客運客氣)' of the date of conception was studied. Results & Conclusions : The theory of calculating the date of conception with the date of birth applies the theory of the various combinations of the ten heavenly stems. The gestation period for those born on the day of the rabbit and chicken are either 246 or 306 days, while for those born on the day of the tiger and monkey, 256 days. For those born on the day of the cow or the lamb, 266; for those born on the day of the rat or horse, 276; for those born on the day of the snake or the pig, 286; for those born on the day of the dragon or the dog, 296 days. Once the date of conception is fixed, the visiting circuit and qi is estimated, and a matching formula is chosen and applied.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.12
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• pp.1337-1344
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• 2007

It is shown that inverted ${\pi}$ feeder affects the gain improvement for the internal antenna of mobile phone. Generation of current on the inverted ${\pi}$ feeder, by the modification of conventional feeding structure for the PIFA and IFA, can apply T matching theory to the new feeder. Therefore, inverted ${\pi}$ feeder based on the T matching theory makes higher radiation resistance, and also increases the gain. To verify inverted ${\pi}$ feeding effect, feeder is applied to GSM/DCS dual band conventional PIFA, and measured return loss and patterns. By measurement, it's shown that this new feeding antenna has $0.23{\sim}0.84$ dB higher average gain for GSM band and $0.01{\sim}1.74$ dB higher average gain for DCS band than conventional fed PIFA without resonant frequency change.

• Journal of Power Electronics
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• v.16 no.3
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• pp.1110-1121
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• 2016

The mathematical model of a three phase PWM converter under the stationary αβ reference frame is deduced and constructed based on a Proportional-Resonant (PR) regulator, which can replace trigonometric function calculation, Park transformation, real-time detection of a Phase Locked Loop and feed-forward decoupling with the proposed accurate calculation of the inductance voltage vector. To avoid the parallel resonance of the LCL topology, the active damping method of the proportional capacitor-current feedback is employed. As to current vector error elimination, an optimized PR controller of the inner current loop is proposed with the zero-pole matching (ZPM) and cancellation method to configure the regulator. The impacts on system's characteristics and stability margin caused by the PR controller and control parameter variations in the inner-current loop are analyzed, and the correlations among active damping feedback coefficient, sampling and transport delay, and system robustness have been established. An equivalent model of the inner current loop is studied via the pole-zero locus along with the pole placement method and frequency response characteristics. Then, the parameter values of the control system are chosen according to their decisive roles and performance indicators. Finally, simulation and experimental results obtained while adopting the proposed method illustrated its feasibility and effectiveness, and the inner current loop achieved zero static error tracking with a good dynamic response and steady-state performance.