• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 춘계학술대회 논문집
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• pp.788-792
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• 2013

There are three significant noises from the sunroof while driving. Among them, sunroof tilt-up noise has mainly high-frequency characteristics in the side and rear openings of sunroof. Because of complex structures to operate sunroof, significant flow disturbance makes strong turbulent noise. In this study, sunroof tilt-up noise was predicted by using numerical simulation code and the results were compared with experimental data.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.272-276
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• 1996

This study deals with the speed control of an overcentered variable-displacement hydraulic motor on a constant pressure network, which is noted for its high system efficiency fast dynamic response and energy recovery capability. The speed control characteristics of the conventional cascade PI controller are largely affected by load-torque disturbances. To obtain robust speed control despite torque disturbances, the load torque is estimated by an observer based on a mathematical model and compensated for by a feedforward loop. It is shown by experiment that robust speed control may be obtained with the proposed controller. The experimental data agree fairly well with the theoretical analysis.

• 한국자동차공학회논문집
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• 제5권3호
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• pp.172-181
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• 1997

The dynamic characteristics during gear ratio change including the disturbance of output torque has been one of the most important issues in the study of automatic transmissions of passenger cars. In this paper, to investigate the dynamic characteristics of a passenger car automatic transmission during gear ratio change, a dynamic model of the driveline of a passenger car focused on the automatic transmission is proposed and the dynamic simulation program is developed. The results of the simulation show good agreements with the experimental data, which process the use fullness of the dynamic model and the simulation of the driveline.

• 공학교육연구
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• 제19권2호
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• pp.3-7
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• 2016

A flow control system was designed and fabricated to control the flow rate of liquid through the pipe. This control system was composed of hardwares and software, hardwares as controller, gate valve, orifice meter and data aquisition board and software as National instruments Labview program. Control of flow rate was executed by adjusting the pneumatic valve located at the center of pipe line based on the control signal generated by LabView PID control algorithm, which converts analog signal measured by pressure difference of orifice to digital signal to adjust pneumatic valve. For the controller setup Ziegler-Nichols tuning technique was applied and control performances were investigated for not only the disturbance but also the set point changes. Developed system showed good control performances in flow control enough to use as teaching tool of feedback control theory and practice in university, and also as industrial application.

• 종양간호연구
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• 제5권2호
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• pp.97-106
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• 2005

Purpose: This descriptive correlation study was to identify the influencing factors on fatigue of patients undergoing radiotherapy for breast cancer. Method: One hundred twenty-six breast cancer patients were recruited from a radiotherapy clinic of two university hospitals. Data were collected using a package of questionnaires consisting of the Symptom Experience Scale, mood disturbance scale, and Social Support Scale. Results: The mean score of the fatigue, physical status, emotional status, and social support was 4.18, 21.96, 100.95, and 3.70, respectively. Family support and health profession support were 3.94 and 3.47, respectively. Fatigue and physical status, fatigue and emotional status, physical status and emotional status were found to have statistically positive correlations. But emotional status and social support were found to have statistically negative correlation. Stepwise multiple regression analysis showed that the influencing factors on fatigue were emotional status, marital status, and physical status which explained 64.4% fatigue of breast cancer patients.

• 융합보안논문지
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• 제5권2호
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• pp.65-74
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• 2005

최근 컴퓨터 네트워크의 발전에 따라 해킹사고도 급증하고 있으며 그 방법도 다양해지고 있다. 이러한 시기에 정보보호에 대한 관심이 높아지면서 많은 기업이 각종 보안시스템을 도입하고 있다. 그러나 해킹에 대응하기 위해서 대부분의 보안장비가 독자적인 이기종간의 기술을 적용해 제품간의 연동과 보안요소만으로 대처하기에는 많은 어려움이 있고, 이를 운용하는데 엄청난 조직, 장비, 인력 소요가 증대되고 있는 실정이다. 이러한 문제점을 해결하고자 이기종간 침입탐지 정보에 대한 보안요소를 통합하여 해킹으로부터 효율적으로 대응할 수 있는 웹 기반 관리 시스템을 설계 및 구현하였다.

• 수면정신생리
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• 제27권1호
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• pp.8-15
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• 2020

Sleep disorder in chronic obstructive pulmonary disease (COPD) is common and typically is associated with oxygen desaturation. The mechanisms of desaturation include hypoventilation and ventilation to perfusion mismatch. Despite the importance of sleep in patients with COPD, this topic is under-assessed in clinical practice. Impaired sleep quality is associated with more severe COPD and may contribute to worse clinical outcomes. Recent data have indicated that specific respiratory management of patients with COPD and sleep disordered breathing improves clinical outcomes. Clinicians managing patients with COPD should pay attention to and actively manage symptoms of comorbid sleep disorders. Management of sleep-related problems in COPD should particularly focus on minimizing sleep disturbance.

• Journal of Ship and Ocean Technology
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• 제4권2호
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• pp.1-12
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• 2000

The present study concentrates on the weak-scatterer hypothesis for the nonlinear wave-body interaction problems. In this method, the free surface boundary conditions are linearized on the incoming wave profile and the exact body motion is applied. The considered problems are the diffraction problem near a circular cylinder and the ship response in oblique waves. The numerical method of solution is a Rankine panel method. The Rankine panel method of this study adopts the higher-order B spline basis function for the approximation of physical variables. A modified Euler scheme is applied for the time stepping, which has neutral stability. The computational result shows some nonlinear behaviors of disturbance waves and wave forces. Moreover, the ship response shows very close results to experimental data.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제9권3호
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• pp.185-190
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• 2009

A scheme of expert system based on iterative learning control is proposed. Iterative learning control can obtain control experience from the historical data to build the knowledge base of expert system. Considering some uncertain factors, a flexible measure is adopted in iterative learning control (ILC). Simulation proves the feasibility and effect of the air conditioning control expert system based on flexible iterative learning control (F-ILC). Finally, a feedback compensation unit is incorporated against irregular heavy disturbance.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 가을 학술발표회 논문집
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• pp.133-145
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• 2001

This paper presents quality and measure controls of Plastic Board Drains(PBD) for improvement of soft ground. Laboratory and field tests has been carried out to evaluate the quality of PBD focussing on : discharge capacity of flow area; permeability of filter sleeve; migration of fine particles; deformed shape of PBD; consolidation of clay in the close vicinity of PBD; tensile strength of PBD; long-term consolidation behavior of clay-PBD. Test results show that the quality of PBD is sufficient to perform the improvement of soft silty and clayey ground. But, geotechnical engineer must make efforts minimizings of PBD damage and ground disturbance, continuity of drainage system during construction. Adequate monitoring system should apply at ground focussing on number, location, and accuracy of geotechnical instrumentation, measurement and evaluation of data for ground behaviour.