• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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• pp.179-182
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• 2003

A simulation on bootstrapping circuit has been performed by modelling a coaxial cable as a transmission line. It is shown that the bootstrapping circuit could be unstable due to the transmission line effect though an ideal amplifier is used. While the conventional bootstrapping circuit does not cancel the input capacitance of the input buffer, a new bootstrapping circuit that cancels input capacitance of the input buffer has been proposed. The proposed bootstrapping circuit consists of the input buffer of which gam is larger than 1 and a feedback resistor to control the loop gain. The proposed bootstrapping circuit has higher input impedance than that of the conventional circuit.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.477-482
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• 2002

This research is concerned with the study of an active vibration absorber using piezoelectric actuators and Isolation pad. The active isolation system consists of 4-pairs of PZT actuators bonded on the surface of an aluminum plate and a passive damping material. The active system is connected to the passive system in series. The Signals of the accelerometers are fed into the PZT actuator through the controller. We proposed a new control technique which can deal with the shock as well as the base excitation in this study. The Positive Acceleration Feedback(PAE) tuned to the natural frequency of the vibration isolation system is used to suppress the vibrations caused by the shock using the top accelerometer signal. The Negative Acceleration Feedback (NAF) based on the base acceleration signal is used to counteract the base motion. Experimental results show that the proposed active vibration isolation system can suppress vibrations.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.721-724
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• 2002

This study deals with a dynamic behavior analysis of pump control regulator varied the swash plate tilting angle with the positive and negative direction. To accomplish it's purpose, modeling and displacement response analysis about principal parts (spool, servo piston, feedback lever, sleeve) of pump control regulator was performed. We have been able to verifying the propriety of servo mechanism and design parameters of pump control regulator by research results. So, it respect to utilized with useful research data at variable displacement control valve development of variable displacement piston pump.

• 대한안전경영과학회지
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• 제13권1호
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• pp.167-173
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• 2011

This paper reviewed the relationship between job characteristics and incremental innovation, and the moderating effect of tenure. The results of multiple regression analysis, based on the responses from 241 employees in service industry, showed that job variety, identity, importance, autonomy and feedback have positive relationships with incremental innovation. In moderating effects, tenure interacts with variety and identity to have positive effects on incremental innovation, but tenure interacts with job importance, autonomy and feedback to have negative effects on incremental innovation.

• 한국통신학회논문지
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• 제10권3호
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• pp.105-114
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• 1985

無條件 安定인 超高周波用 바이폴라 트랜지스터를 使用하여 S 밴드에서의 發振器를 具現하여 보았다. 發振器는 周波數安定한 3個의 同一한 誘電體 共振器를 利用하여 製作되었으며 負性 抵抗은 3포트 散亂係數(3-Ports Scattering Parameters) 方法으로 求하였다. 本 論文에서는 誘電體 共振器를 궤환素子로 使用하여 콜렉터, 베이스에서 各各 41dBm, 10dmB의 最大出力을 얻을 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.54-57
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• 1987

A new method optical short pulse generation using diode lasers under the negative electro-optic feedback are proposed. The self-pulsing is induced by feedback itself and the pulse is formed by the interaction of feeback signal and the dynamics of the diode laser. The simulated pulse width is on the order of picosecond with several GIIz repetition rates.

• Nuclear Engineering and Technology
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• 제55권5호
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• pp.1665-1670
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• 2023

It is shown that in the IBR-2M reactor by the end of the reactor cycle, changes in dynamics are observed associated with a strong weakening of the fast power feedback (PF), as a result of which the reactor becomes oscillatorily unstable. After each week of zero-power operation the negative changes in reactor dynamics disappear and the stability of the reactor is restored. Thus, the reactor undergoes cyclic changes in the oscillatory instability. The correlation between of a fast PF and a slow PF is experimentally observed, which makes it possible to almost completely eliminate the cyclic component of instability by changing the control mode of rods of the control system.

• 전자공학회논문지SC
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• 제40권4호
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• pp.275-281
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• 2003

0.5㎛ 2중 폴리 CMOS 공정을 이용하여 새로운 뉴럴 오실레이터를 설계, 제작하였다. 제안하는 뉴럴 오실레이터는 트랜스콘덕터 및 캐패시터와 비선형 가변 부성저항으로 이루어진다. 뉴럴 오실레이터의 입력단으로 사용되는 비선형 가변 부성저항은 정귀환의 트랜스콘덕터와 가우시안 분포의 전류전압 특성을 지니는 범프 회로를 이용하여 구현하였다. 또한 SPICE 모의실험을 통하여 제안한 오실레이터의 특성분석 후 집적회로 설계를 실시하였다. 한편 흥분성 및 억제성 시냅스로 연결된 4개의 뉴럴 오실레이터로 간단한 신경회로망을 구성하여 그 특성을 확인하였다. 집적회로로 제작된 뉴럴 오실레이터에 대하여 ± 2.5 V 전원 조건하에서 측정된 결과를 분석하고 모의실험 결과와 비교한다.

• 농촌의학ㆍ지역보건
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• 제23권1호
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• pp.91-108
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• 1998

This study was conducted to use the feedback of health personnel to improve the Visiting Health Service. The data was collected from 471 Home Health Workers serving 24 local health organizations in the Kyung-Pook province. 62.5% of the respondents were men under thirty-nine years of age. 92.8% of the respondents are married. 47.1% had degrees from junior colleges. It was ascertained 52.7% of the workers visited their patients six to twelve times within a six month period. And one to three patients were visited per day by one worker. Workers of older age, higher job position, and more experience were more positive in their feedback about the program. In addition, local health center employees, including nurses, were more positive about the program. Younger workers with a higher level of education, less experience, and lower job position had more insight into the problems of the program. Deeper insight into these problems led to a more negative conception of the program. Older workers with higher ranking jobs were found to be most competent. in their jobs. Workers at the main health center were assessed higher than the workers at the health sub-center or the primary health post. In addison nurses at all centers were found to be slightly more competent than the nurses' aide. The primary health post established the highest degree of patient satisfaction. It was discovered that the more positive the workers felt about the program, the higher their patient satisfaction feedback. There was a positive correlation between management assessment and patient satisfaction. This means that better program management was found to produce higher patient satisfaction. Workers feel being more educated about patient management would lead to better service. However, they take no action to produce these results. Where the problems of the system are most commented upon, the need for further education is greatest. Through multiple regression analyses it is apparent that the assessment of patient management is the greatest variable affecting patient satisfaction of patients is dependent on the management by the visiting health worker. Therefore, the development of the visiting health program is highly dependant on the feedback of those workers with a negative conception of the program. So the development of programs, motivation, education and training must be established. These works would lead to active participation by visiting health workers in the improvement of the Visiting health program.

• Nuclear Engineering and Technology
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• 제41권8호
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• pp.1053-1064
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• 2009

The existence of a large sodium pool in the KALIMER, a pool-type LMR developed by the Korea Atomic Energy Research Institute, plays an important role in reactor safety and operability because it determines the grace time for operators to cope with an abnormal event and to terminate a transient before reactor enters into an accident condition. A two-dimensional hot pool model has been developed and implemented in the SSC-K code, and has been successfully applied for the assessment of safety issues in the conceptual design of KALIMER and for the analysis of anticipated system transients. The other important models of the SSC-K code include a three-dimensional core thermal-hydraulic model, a reactivity model, a passive decay heat removal system model, and an intermediate heat transport system and steam generation system model. The capability of the developed two-dimensional hot pool model was evaluated with a comparison of the temperature distribution calculated with the CFX code. The predicted hot pool coolant temperature distributions obtained with the two-dimensional hot pool model agreed well with those predicted with the CFX code. Variations in the temperature distribution of the hot pool affect the reactivity feedback due to an expansion of the control rod drive line (CRDL) immersed in the pool. The existing CRDL reactivity model of the SSC-K code has been modified based on the detailed hot pool temperature distribution obtained with the two-dimensional pool model. An analysis of an unprotected transient over power with the modified reactivity model showed an improved negative reactivity feedback effect.