• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.66-72
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• 2000

Commercial eddy current dynamometers control the torque of ratating body (poer supply machine) with the field coil current being operated as a braking force. In this paper, we studied about the relation between the field coil current and the torque load of eddy current dynamometer. By the torque measuring analysis of eddy current dynamometer, it is linear relation between the brake force measured from the torque meter (e.g. load cell, strain gage or spring balance etc.) which is installed at the case of dynamometer and the multiply of shaft rpm by the square of field coil current (N$\times$Ia2). To prove the relation, it was experimented and showed that the torque operated by the rotating body can be measured with the shaft rpm and the field coil current of eddy current dynamometer. This result shows a possibility that eddy current dynamometer can measures the torque of rotating body without special torque measuring devices.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.321-323
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• 1998

이 논문에서는 크기가 큰 III-Conditioned Matrices 정방행렬의 좌측 또는 우측 역행렬 계산시 계산상의 정확도를 향상시키는 알고리듬에 대하여 기술한다. 이 알고리듬은 대상 행렬의 행벡터들을 Input으로 하고 해당 Input 벡터가 몇번째 행 벡터인지를 나타내는 단위 벡터를 Target 벡터로 하며 초기 Weight 값으로 Pivoting을 겸한 Gauss소거법을 적용하여 얻은 역행렬을 사용하는 Single Layer 인공신경망에 적용하는 역전파 알고리듬과 흡사한 것이다. 각각의 Input 행 벡터에 대하여 역행렬의 열 벡터들이 점진적으로 직교가 되거나 평행이 되도록 근접시키므로써 모든 Input 행 벡터들이 열벡터들에 비교적 균일하게 직교 또는 평행이 되도록 학습시키는 알고리듬이다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.9
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• pp.1780-1787
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• 1992

Experiments have been performed on the thermal behavior in a liquid saturated porous medium in a system to simulate a single well aquifer thermal energy storage system. The principal interests in this study are the combined effects of forced and natural convection. Significant buoyancy flow due to natural convection is developed quickly as the temperature difference between the injection and original aquifer temperature increases. Theoretical model under simplified assumptions (called simple buoyancy flow model in this study) has been developed. The results of this model agree well with the experiments. The effects of buoyancy flow on the recovery factor are also examined in this study.

• 한국지구과학회:학술대회논문집
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• 2002.02a
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• pp.79-79
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• 2002

• Proceedings of the Korean Society of Life Science Conference
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• 2001.02a
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• pp.56-56
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• 2001

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.162-163
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• 2012

계통연계 인버터에서 계통전압과 위상을 일치시키기 위한 PLL은 필수이다. 기존의 PLL의 경우 계통전압에 불평형이 발생하면 계통의 위상을 정확하게 추종할 수 없기 때문에 제어를 할 수 없게 되고 이는 시스템에 심각한 영향을 미칠 수 있다. 따라서 불평형 전압이 발생하여도 정확하게 위상을 추종할 수 있는 기법의 필요하다. 본 논문에서는 SOGI(Second - Order Generalized Intergrator)를 소개하고 시뮬레이션과 실험을 통해 그 타당성을 검증한다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.11a
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• pp.276-279
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• 2005

A review of how the functions of two or more independent variables can be approximated by using fuzzy systems is provided in this paper. We start with an exact represention of a linear interpolation function of two independent variables by using a fuzzy system. Next, we describe how this function can be approximated by another fuzzy system with a lesser number or with a desired number of output fuzzy sets. Thus, a reduction of the storage needed is achieved by storing the fuzzy rules or equivalently the output fuzzy set numbers instead of storing the whole discrete function values. A description on how the cubic spl me interpolation function can be represented exactly by using the fuzzy system method is provided, along with a few examples where fuzzy rule tables with a size of 7$\times$7 provide a representation of the functions with relative errors of the order of $10^{2}$ or less.

• Conservation Science in Museum
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• v.12
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• pp.25-34
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• 2011

This study examined conservation process of white porcelain bottle with phoenix and peony design poly chrome, recovery of golden powder painted porcelain being damaged and colored, and recovery material and conservation methods by using a variety of experiments. Not only traditional method but also modern method can recover golden powder painted area being damaged and/or peel off, and suitable recovery was found out by using experiments. The golden powder paint of pattern edge was recovered not by traditional method but by modern method of golden powder paint with acrylic paint and binder.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.12
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• pp.90-93
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• 2003

KISTI는 기관의 역할을 만들기 위한 노력이나 비즈니스 모델의 개발을 위한 노력은 상대적으로 덜 필요한 기관이다. 그만큼 하는 일이 선명하다. 슈퍼컴센터와 정보서비스를 한 기관에서 제공하는 것에 대한 이견은 아직도 있을 수 있으나 KISTI의 역할은 이제 굳건히 정립되었다고 볼 수 있다. 이제 KISTI의 본연의 업무 이외의 오버헤드에 들이는 시간을 줄이고 정말 해야할 작업에 집중할 수 있는 환경을 확보하는 노력을 해야할 시점이다. 작년 하반기와 올 상반기는 기관평가에 대한 부담으로 KISTI본연의 작업에 써야할 시간을 많이 빼앗기고 있는 인상을 받았다. 이것은 KISTI 내부의 구성원들과 KISTI를 평가하는 상위기관에서 같이 노력을 해야할 일이다.

• Health Policy and Management
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• v.34 no.1
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• pp.78-86
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• 2024

Background: The purpose of this study was to determine the effectiveness of the specialty hospital system by comparing the medical use of inpatients who had artificial joint replacement surgery in specialty hospitals and non-specialty hospitals. Methods: This study utilized 2021-2022 healthcare benefit claims data provided by the Health Insurance Review and Assessment Service. The dependent variable is inpatient medical use which is measured in terms of charges per case and length of stay. The independent variable was whether the hospital was designated as a specialty hospital, and the control variables were patient-level variables (age, gender, insurer type, surgery type, and Charlson comorbidity index) and medical institution-level variables (establishment type, classification, location, number of orthopedic surgeons, and number of nurses). Results: The results of the multiple regression analysis between charges per case and whether a hospital is designated as a specialty hospital showed a statistically significant negative relationship between charges per case and whether a hospital is designated as a specialty hospital. This suggests a significant low in charges per case when a hospital is designated as a specialty hospital compared to a non-specialty hospital, indicating that there is a difference in medical use outcomes between specialty hospitals and non-specialty hospitals inpatients. Conclusion: The practical implications of this study are as follows. First, the criteria for designating specialty hospitals should be alleviated. In our study, the results show that specialty hospitals have significantly lower per-case costs than non-specialty hospitals. Despite the cost-effectiveness of specialty hospitals, the high barriers to be designated for specialty hospitals have gathered the specialty hospitals in metropolitan and major cities. To address the regional imbalance of specialty hospitals, it is believed that ease the criteria for designating specialty hospitals in non-metropolitan areas, such as introducing "semi-specialty hospitals (tentative name)," will lead to a reduction in health disparities between regions and reduce medical costs. Second, it is necessary to determine the appropriateness of the size of hospitals' medical staff. The study found that the number of orthopedic surgeons and nurses varied in charges per case. Therefore, it is believed that appropriately allocating hospital medical staff can maximize the cost-effectiveness of medical services and ultimately reduce medical costs.