• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1998년도 춘계학술대회논문집
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• pp.194-199
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• 1998

The purpose of this study is conducted to evaluate the psycho-physiological effects of the dynamic lighting on VDT workers and to establish the dynamic lighting design guides. The main experimental factors are changes of illuminance. There were five conditions including 1) ripid change, 2) slow change at 300lx .approx. 500lx, 3) a static illuminance level at 300lx, and 4) rapid chante, 5) slow change at 200lx .approx. 300lx. The ranges of change were set typical illuminance level for the simple visual task requirement and reasonable to a VDT task ; 200-300-500lx. The psycho-physiological measurements used were EEG, R-R interval, CFF, near point accommodation, feeling perceived fatigue, and work performance. Analysis of psycho-physiological factors shows that higher illumination level conditions are more affirmative effects than lower on VDT workers under 500lx except for the results of feeling perceived fatigue. And about the speed of changes of illuminance level. The conditions of slow change were better than the others in terms of the work performance as well as psycho-physiological results.

• 한국산업융합학회 논문집
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• 제7권1호
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• pp.129-132
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• 2004

In order to determine the effective way of measuring the Mode I stress intensity factor, $K_I$, by means of the alternating current potential drop(ACPD) technique for a material containing a two-dimensional surface crack, the change in magnetic flux density above the cracked specimen surface was studied experimentally. The change in magnetic flux in the air above the cracked specimen made of aluminum alloy is measured by changing the load by four-point bending. The magnetic flux in the air is almost not changed by increasing the load in teh specimen. The change in potential drop due to load is not caused by the change in electro-motive force induced in the coiled measuring system. This experimental result agree to the result of theoretical analysis in reference 7).

• 오토저널
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• 제8권1호
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• pp.62-74
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• 1986

The simulation of power cycle and unsteady gas exchange processes in the inlet and exhaust systems of the single-cylinder 2-stroke cycle compression ignition engine was studied in this paper. In power cycle process, the single-zone model proposed by Whitehouse and Way was used, and the convective and radiative heat transfer from cylinder contents to surroundings was considered. To solve the equations for gas exchange process, the generalized method of characteristics including area change, friction, heat transfer and entropy gradients was used. Also with the path line calculation, the entropy change along the path line and the variation of specific heat due to the change of temperature and the composition of cylinder gas were considered. As a result of the simulation, the change of pressure and temperature in the cylinder against the crank angle, the rate of net heat release, and the change of properties at each point in the inlet and exhaust pipe against the crank angle were obtained. The engine performances under various operating conditions were also calculated.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2002년도 종합학술발표회 논문집 Vol.12 No.1
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• pp.49-53
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• 2002

In this thesis, approximated design formulas for bandpass filters using changed coupling nodal point resonators are derived. The formulas take into account the arbitrary coupling node of lumped and distributed resonators. The advantage of this filter is its abilities to change freely the coupling structure between two resonators. Using the design formulas two filters were designed and simulated. Their responses verified the formulas.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 춘계학술대회 논문집
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• pp.213-217
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• 1993

This paper presents an end-point of 1-link flexible robot arm with a tip-mass by using self-turning fuzzy algorithm. The arm is mounted on a translational mechanism driven by a ballscrew, whose rotation is controlled by CD servomotor. Tip position is controlled so that it follows a desired position. A feedback signal is composed of both the tip-displacement error and change in error. This paper gives the experimental tip responses according to the variations of tip-mass and beam-length, and also showes the effects of reducing the residual vibrations occuring at the end-point.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 추계학술발표회
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• pp.114-114
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• 2017

• 비파괴검사학회지
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• 제10권1호
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• pp.65-72
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• 1990

Comparison of acoustic emission, ultrasonic testing and crack gauge in 3-point bending testing have been studied. As the results, COD is indirectly assumed by strain gauge rate and grid pitch width when crack gauge grid is out. Acoustic emission is qualitatively able to measure crack growth by total count but ultrasonic testing has a difficulty in measuring it because of echo height fluctuation according to the change and pressure of UT. probe.

• 한국시뮬레이션학회논문지
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• 제7권2호
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• pp.115-123
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• 1998

A simulation is performed to investigate the effect of the pipe supports on the change of the natural frequencies of curved pipe systems containing fluid flow, for different elbow angles and geometry of the pipe systems. Based upon the Hamilton's principle, the equations of motions are derived, and the finite element equation is constructed to solve the corresponding eigenvalue problem. The angles of elbows do not affect the change of the fundamental natural frequency, but affect the change of the third or higher natural frequencies. Without any support, the change of the fundamental natural frequency due to the geometric change is smaller than the change of the second or higher natural frequencies. The more curve parts exist in the pipe system, the less change of lower frequency range, compared with the change of higher frequency range, is observed. Spring supports can be used to reduce the fundamental natural frequency, without change of the second or higher natural frequencies. To avoid resonance, which is critically dangerous from the view point of structural dynamics, the mechanical properties such as stiffness or the location of pipe supports are need to be changed to isolate the natural frequencies from the frequency range of dominant vibration modes.

• 대한한방체열의학회지
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• 제4권1호
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• pp.45-53
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• 2005

Objectives; Hapkok(L14) and Taechung(Liv3) are acupuncture points located on both sides of each foot and hand of the human body. These two points are called sakwan points. Matching these acupuncture points have a significant reason in points of not only regulating the circulation of Yin-Yang as a source point of each meridian, but also playing a basic role of twelve meridian by controling circulation of ki and blood in the whole body. There are already related documents and studies on stimulating sakwan points. Since those papers mostly studied on either hapkok or taechung, we came to have a doubt of stimulating the two point at the same time when an inbalance of Yin-Yang and ki-blood appears. Accordingly, we got to investigate how thermogram of body changes after applying an acupuncture on sakwan points. Our study is as follows ; Methods; Our study was performed on 30 normal cases(M:F=17:13) with no past history to observe the effects of the acupuncture. We measured temperature of abdomen and the back of both hands by D.I.T.I(Digital Infrared Thermographic Imaging) before and after acupuncture on sakwan points. Results and Conclusion; The thermographic change on abdomen was $0.51{\pm}0.71^{\circ}C$. Temperature of abdomen after acupuncture was higher than before acupuncture with high validity(p <0.01). And the thermographic changes on the back of both hands were right hand $0.54{\pm}1.17^{\circ}C$, left hand $0.56{\pm}1.28^{\circ}C$. Temperature on the back of both hands after acupuncture was higher than before acupuncture, but the difference between them had little validity(p <0.01) In addition, we found that it doesn't necessarily follow that the thermographic changes on abdomen and back of both hands after acupuncture on sakwan points happen concurrently.

• 복식
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• 제55권8호
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• pp.85-98
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• 2005

This Study is to analyze characteristics of costume change of according to the status of character succeeding the investigation of the ceremonial costume change in historical TV dramas that The Empress Myungsung entered. For this study, the costume images among historical TV dramas, that Myungsung entered, '500 years of Chosun Dynastyv, Taewongun(1990, MBC)', 'The Glorious Dawn(1993, KBS1)', 'The Empress Myungsung(2001, KBS2)'were used: The characteristics of the costume change of main character are as follows. First, main character's costume has been increase gradually in number and item. Second, Especially in the last work,'The Empress Myungsung', the royal costume based on historical evidence in aspects of silhouette, but it didn't according to the historical costume in aspects of color and textile. Nevertheless the costume reveals the status of each person significantly. Third, the costumes of the recent historical drama appears as a optical symbol that represents historical view point and different interpretation of each drama. Therefore the costume according to the status of the character wrong from the historical point of view. Consequently, TV costume in historical drama Myungsung entered has been focused on the beauty of the screen and dramatic effect than historical viewpoint. So the costume have been to be an essential visual part by means of the symbol revealed the purpose.