• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2000년도 종합학술발표회 논문집 Vol.10 No.1
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• pp.121-124
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• 2000

In mobile communication repeaters, very small size with sharp skirt response is needed as the BPF performances. The passband flatness of the proper BPF becomes very bad due to the low value of the resonator Q-factor used in the BPF. Which could girt serious level unbalance between channels. This flatness problem can he solved by a kind of compensated filler, which has 'reverse-curve'or 'concave shape'as the passband response. In this paper, the design method of the proposed 'concave bandpass filter'without matching and loss problems is presented. The designed and fabricated filter can properly and easily compensate the convex or bad flat passband response.

• Journal of Advanced Marine Engineering and Technology
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• 제28권7호
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• pp.1145-1151
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• 2004

The experiment of thermal performance about cross flow type cooling tower was conducted in this study. Generally the ambient air condition can affect the thermal performance of cooling tower to improve or not. However it is hard to control the cooling water temperature that we want under bad air condition or during rainy season. In this paper, the effect of variables, which the ambient air have. especially wet-bulb temperature, are experimentally investigated for controlling the cooling water temperature more successfully. The result is that there is appropriate air flow rate in respective air condition to preserve the cooling performance in the cooling tower and the maximum air flow rate can't overcome the approach under bad air condition.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1243-1248
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• 2003

It is very important to measure linear motion accuracy of NC lathe as it affects all other parts of machines machined by them in industries. If the motion accuracy of NC lathe is bad, the dimension accuracy and the change-ability of works will be bad in the assembly of machine parts. In this paper, computer software systems are organized to measure linear motion of ATC(Automatic tool changer) on zx plane of NC lathe using two linear scales and the time pulses coming out from computer in order to get data at constant time intervals from the linear scales. And each sets of error data obtained from the test is discripted to plots and the results of linear motion errors are expressed as numerics by computer treatment.

• 대한임베디드공학회논문지
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• 제10권1호
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• pp.7-12
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• 2015

As smart phone became popular, its excessive uses cause adverse effects called smart-phone syndrome such as Turtle-neck syndrome in physical side and smart-phone addiction in mental aspects. Turtle-neck syndrome incurred by incorrect posture when you watch smart-phone, which causes a serious health problems. However, these syndromes can be detected by gyro-sensor and timer, and prevented by correcting the posture and halting the function with smart-phone application (App). Thus, this paper proposes App that helps user to realize bad posture and addiction to smart-phone, and to acquire the correct habit by inducing user to stretch neck or to stop operation with warning message. If we tried to adjust bad posture and addiction in using smart-phone through this application, the social losses from smart-phone syndrome would be minimized as a result.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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• pp.101-108
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• 2004

It is very important to diagnose state of knife and strip cutting face in real time in the side trimming process due to improvement of quality of trimming face. In this study, diagnosis system for knife and strip cutting face was developed. CCD camera was installed at the both side of strip in the entry of burr masher roll. This system offer to operator the diagnosis result that was analyzed image obtained from CCD camera. As a result, bad quality of trimming face is decreased below 1/10 and knife breakage is detected $100\%$.

• 복식문화연구
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• 제10권1호
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• pp.28-36
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• 2002

The purposes of the study were to investigate the effect of garment category, fashion-level and wearer's body type on the basis of temporal stability and to extend the contextual framework. The result was as follows 1) On the basis of temporal stability, Korean style, classic style, and large body type have more temporal stability than western style, fashionable style, normal body type. 2) On the basis of temporal stability of impression dimension, impression of appearance knave most temporal stability, next good-bad, next evaluation, next potency, and sociability. 3) In an interaction effect between measuring time and impression of evaluation, western, fashionable, classic style have the greatest interaction effect. In an interaction effect between measuring time and impression of appearance, western style, normal body type have the greatest interaction effect. In an interaction effect between measuring time and impression of good-bad, western, fashionable style have the greatest interaction effect. It is concluded that the results support the context framework on impression formation.

• 한국생산제조학회지
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• 제7권3호
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• pp.51-51
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• 1998

It is very important to test linear cycle positioning accuracy of Machining centers as it affect all other machines machined by them in industries. For example, if the linear positioning accuracy of each axes directions is bad, the size of works will be wrong and the change-ability will be bad in the assembly of machine parts. In this paper, measuring systems are organized to measure linear displacements of table or spindle of machine center using laser interferometer, magnescale and tick pulses comming out from computer in order to get data at constant time intervals from the sensors. And each set of data gotten from test is expressed to a plots by computer treatment and the results of linear positioning error motion is estimated to numerics by statistical treatments.

• 한국잠사곤충학회지
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• 제19권1호
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• pp.15-18
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• 1977

누에의 인공사료에 있어서 옥수수의 수병을 조직유원으로서 이용할 수 있지를 알기 위해서 옥수수의 수병을 함유한 인공사료가 누에의 성장에 미치는 영향을 조사하였던 바 다음과 같은 결과를 얻었다. 1. 옥수수의 수병을 함유한 인공사료는 누에의 섭식에 주는 나쁜 영향은 없는 것 같다. 2. 옥수수의 수병을 함유한 인공사료는 누에의 성장 및 견질에도 주는 나쁜 영향은 없는 것 같다. 3. 이상의 결과를 종합해 볼 때, 옥수수의 수병은 누에의 인공사료에 있어서 하나의 총섬유원으로 적당할 것 같다.

• 한국치위생학회지
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• 제14권2호
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• pp.197-204
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• 2014

Objectives : The purpose of the study is to examine the effect of the indoor environmental factors of dental hygienists on physical symptoms. Methods : The subjects were 210 dental hygienists in dental hospitals and clinics in Seoul, Gyeonggi Province, Incheon and South Chungnam Province from May 1 to June 20, 2013. Results : There were significant differences between the presence or absence of windows in respiratory symptoms and eye symptoms. Room temperature, bad smell, and dry humidity had significant influences on physical and respiratory symptoms. Dermatological and ophthalmological symptoms were affected by dryness, smell and dusts. Dusts and bad smell also had influences on a variety of subjective symptoms. Conclusions : The indoor environments of dental hospitals and clinics affect the respiratory, dermatological, and ophthalmological symptoms because various hazardous materials are generated by the dental treatment. Therefore dental hygienists should have a correct understanding of bacteria, dusts and bio-aerosol in order to ensure the successful environmental control.

• 대한전기학회논문지
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• 제38권4호
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• pp.269-278
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• 1989

When the induction motor is operated by CSI, the commutation capacitance in the CSI circuit is increased according to the increase of large capacitor system. The output voltage spikes are generated at the moment of charge and discharge of the commutation capacitor. Also, since output current comprise a great number of harmonics, torque ripples of the motor are generated, having bad effects on the motor. In this study, by adopting the 18-phase multiple high Frequency Current Source Inverter (HFCSI), torque ripples generated by the voltage spikes are mostly eliminated except the 17th and 19th harmonics. To reduce the voltage spikes comprised in the output voltage, particularly, the methods of eliminating the cause of bad effect upon the motor are proposed in this paper. In the proposed method, by using additional voltage Clamping Curcuit (VCC), it is possible to select the values of commutation capacitor energy loss in commutating, the commutating capacitor, and the capacitor in the clamping circuit.