• 한국정밀공학회지
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• 제16권10호
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• pp.109-117
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• 1999

In this paper, a direct adaptive control, based on Lyapunov Function Candidate, is applied to a nonlinear Gunner's Primary Stabilized Head Mirror system to derive a parameter adaptation scheme; furthemore, a nonlinear sliding mode control, but also compensating the error in identification of the parameters which are even varying of have uncertain values. The performance of the adaptive controller is determined by the tracking ability to a desired model under some disturbances and the slowly varying parameters of the system. Both adaptive scheme and sliding mode play an important fole in the improvement of the nonlinear system control.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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• pp.728-730
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• 1998

The control valve positioner is a high gain plain proportional controller which measures the valve stem position and compares it to its setpoint which is the primary controller output. The positioner in effect is the cascade slave of the primary controller. In order for a cascade slave to be effecttive, it must be fast enough compared to the speed of its set point change. This paper describes the positioner transfer function and its effect on the entire control loop characteristic based on the simulation results. The result showed that the control valve and positioner determined the gain and phase angle in the high frequency range, while the primary controller and process determined those of the low frequency range. We can also anticipate the combined characteristics in the whole frequency range when each element's frequency response is known.

• Advances in nano research
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• 제14권1호
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• pp.93-101
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• 2023

This research aims to explore the influence of early entrepreneurial education on cognitive and non-cognitive abilities of male sixth-grade primary school pupils using a randomized pretest-posttest control group design. A total of 45 students were randomly allocated to experimental, active-control, and control groups using a multi-stage random selection procedure. The experimental group was taught entrepreneurship using the Bizworld entrepreneurship education package. The active control group did not get entrepreneurship education but was instructed on a non-entrepreneurship-related issue (hygiene). The Control group received no instruction. The findings revealed that early entrepreneurial education skills impacted noncognitive abilities (such as risk-taking propensity, creativity, self-efficacy, persistence, and need for achievement). Early entrepreneurship education seems to be an effective technique for developing children's non-cognitive abilities in the late years of primary school. As a result, entrepreneurship education may be taught in primary schools, emphasizing the development of non-cognitive abilities, which will affect children's individual, educational, social, and vocational futures and can have long-term advantages for students, families, and society.

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2002년도 춘계학술발표논문집(상)
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• pp.68-72
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• 2002

CIS 응용에서 공간 객체들이 여러 사이트에 걸쳐 중복 저장되어 있다면, 이 객체들의 수정 시 일관성 제어를 위한 중복 제어 기법이 필요하다. 그러나, 일반적인 비즈니스 데이터를 위한 정통적인 중복 제어기법은 공간 데이터에는 그대로 사용될 수 없다. 공간 데이터의 수정은 긴 트랜 션을 필요로 하며, 또한 일반 데이터와 달리 데이터간의 공간 종속성을 지니기 때문이다. 본 논문은 기존의 Primary Copy 중복 제어 기법을 확장하며, time-stamp에 기반하여 Primary Copy 사이트가 변경되는 Floating Primary Copy 기법을 제안한다. 본 논문에서 제안하는 중복 제어 기법은 Primary Copy 사이트를 동적으로 변경함으로써, 긴 트랜 션의 중복 일관성 제어를 지원할 수 있다.

• 한국의료질향상학회지
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• 제26권2호
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• pp.86-94
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• 2020

Purpose: This study aimed to identify current quality control (QC) practices of primary care clinics participating in the National Cancer Screening Program (NCSP) in Korea. Methods: A nationwide survey using a structured questionnaire was conducted among the primary care clinics participating in the NCSP, which were selected by a proportionate stratified sampling. The questionnaire consisted of general information about the responding clinics and the scope of QC activities undertaken. A total of 360 clinics responded and the set of data was then analyzed with Chi-square test and multivariable logistic regression analysis. Results: Among 360 respondents, 332 (92%) reported that they were involved in the QC activities. Most frequently performed QC activities were 'maintenance of facility and instruments' (89%) and 'staff training' (85%). The analysis revealed, with statistical significance (p<.05), that there was an association between certain characteristics of the clinics and the scope of QC activities. These findings also indicated that the diversity of QC practices varies according to the size of the clinics. The clinics screening more types of cancer, those with more screenees, and those with more employees were more likely to implement various QC activities including 'maintenance of facility and instruments', 'external quality control', and 'management of screening data'. Conclusion: To our knowledge, this is the first study to investigate the current status of QC activities conducted among primary care clinics participating in the NCSP. The results of this survey can be used as a basis for further development of policies on quality management of small- and medium-sized primary care clinics in Korea. However, further studies encompassing various aspects of QC activities and management of primary care clinics are needed to assess the current situation in a concise manner.

• Korean Chemical Engineering Research
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• 제58권3호
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• pp.430-437
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• 2020

본 연구에서는 다단제어(Cascade Control)를 위한 안티 와인드업(Anti-windup) 기술을 개발하였다. 다단제어는 외란을 보다 효과적으로 제어하기 위해 내부에 되먹임(Feedback) 제어루프를 추가한 제어구조이다. 단일루프제어(Single-loop Control)와는 다르게 두 개의 제어루프로 이루어져 내부의 종속제어루프(Secondary Control)가 외부의 주제어루프(Primary Control)에 영향을 미치는 특징을 가지고 있다. 산업현장에서 다단제어에 적용하는 기존의 안티 와인드업 기술은 주로 주제어기(Primary Controller)와 종속제어기(Secondary Controller)에 각각 로컬 역연산법(Back Calculation)을 적용하는 것이다. 하지만 이 방법은 종속제어기의 제어출력이 포화되었을 때 발생하는 주제어기의 적분누적(Integral-windup) 현상을 효과적으로 제거하지 못한다. 이를 해결하기 위해 기존 로컬 안티 와인드업 기술을 확대 적용한 두 가지의 다단제어용 안티 와인드업 기술을 제안한다. 첫 번째는 다단 조건부 적분법(Cascade Conditional Integration)이고 두 번째는 다단 역연산법(Cascade Back Calculation)으로 단일루프제어에 적용되어 왔던 로컬 조건부 적분법과 역연산법을 다단제어로 확대 적용하여 다단제어 시스템에서 PID제어기의 적분누적 현상을 방지하고자하였다. 개발한 다단 조건부 적분법과 다단 역연산법은 간단하고 직관적이면서도 종속제어기의 제어출력의 포화로 인해 발생한 적분누적현상을 효과적으로 방지할 수 있고 공정이나 제어기 형태에 상관없이 우수한 제어성능을 유지할 수 있었다. 향후 실제 공정 적용을 통해 신뢰성을 확보한다면 산업현장의 다단제어기 성능을 개선하는데 크게 기여를 할 수 있을 것이다.

• 아동학회지
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• 제3권
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• pp.97-113
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• 1982

Problems This study was aimed to find out the effects of Kindergarten education on primary school child's learning achievement and it's continuance. The specific question to be investigated in this study can he summarized as follows. 1. How did the kindergarten education effect upon primary school child's learning achievement and behavioral development? 2. How did the differences of learning achievement and behavioral development between groups of children attending kindergarten and not attending kindergarten? Methods 1. Subjects One hundred and twenty children of sixth grade and one hundred primary school's teachers were employed 1) Sixty of children were experimented groups who had received kindergarten education. Sixty of Children are Control group who had not received Kindergarten education. The subjects were sampled in N primary school in seoul and Y primary school in Taejeon. Sixty of children were boys and sixty of children were girls. 2) Fifty of teachers were sampled in N primary school in Seoul and Fifty of teachers were sampled in Y primary school in Taejeon. 2. Instrument 1) School cumulative record. School cumulative record was referred to find out the differences of school records on learning achievement in morality, National language, social studies, arithmatics, natural science, gymnastics, music, fine arts and behavioral development in industry, responsibility, coorperation, indeperdence, law abiding spirit between experimental group and control group. 2) Questionnaire paper which constructed 10 articles. Questionnaire paper asked to primary school teachers for effects of kindergarten education. Results The results of date analysis can summarized as follows. 1. Kindergarten education, generally, is regarded effective at least for school work achievement but not so effective for morality and physical education. 2. Kindergarten education is not so effective in all school works of primary school in its continuance since its effectiveness begins to fade away from the 4th grade of primary school. But such continuance tends to be outstanding especially in national language, social subjects and arts. 3. The experiences of kindergarten education is not much helpful to behavioral development during primary school. 4. Primary school teachers recognize that kindergarten education contributes to curriculum work and behavioral development for primary school children.

• 한국소음진동공학회논문집
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• 제19권3호
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• pp.288-293
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• 2009

This study presents the active noise control of duct noise. The duct was excited by a steady-state harmonic and white noise force and the control was performed by one control speaker attached to surface of the duct. An adaptive controller based on filtered x LMS(FXLMS) algorithm was used and controller was defined by minimizing the square of the response of the error microphone. The assemble controller, which is called a hybrid ANC(active noise control) system, was combined with feedforward and feedback controller. The feedforward ANC attenuates primary noise that is correlated with the reference signal, while the feedback ANC cancels the narrowband components of the primary noise that are not observed by the reference sensor. Furthermore, in many ANC applications, the periodic components of noise are the most intense and the feedback ANC system has the effect of reducing the spectral peaks of the primary noise, thus easing the burden of the feedforward ANC filter.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1410-1414
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• 1990

A method of speed sensorless vector control of induction motor is proposed in this paper. This method uses the slip frequency estimated by only the primary voltage and current. As this slip frequency accords with the command value of it, the commanded primary frequency is controlled. The validity of the method is confirmed by the simulation and experimental results.

• 기본간호학회지
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• 제18권2호
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• pp.237-246
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• 2011

Purpose: Family-caregivers of stroke patients usually go through hardship and life style changes during the protracted course of a family member's rehabilitation. There is need for programs to educate family-caregivers to better manage the medical crisis. In this study an evaluation was done of the degrees of burden and well-being experienced by primary family-caregivers following video-guided education (VGE) on rehabilitation and family lifestyle changes. Method: Fifty-eight primary family-caregivers of stroke patients on a neurological ward were divided into VGE (29) and control (29) groups. VGE was started within 7 days of patient admission. Interventions included VGE, counseling, and demonstration - re-demonstration. The control group received standard education but not VGE. Data were analyzed using Chi-square test, t-test, ANCOVA, and Pearson correlation coefficients with the SAS program. Results: The VGE group had a significantly lower score for total burden (F=7.19, p=.010) and for sub-scale of time-dependent burden (F=8.44, p=.005) than the control group. There was a negative correlation between primary family-caregiver burden and well-being (r=-.7151, p<.001). Conclusion: Results suggest that the rehabilitation program using VGE was an effective nursing intervention to reduce the burden of primary family-caregivers of stroke patients.