• 제어로봇시스템학회논문지
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• 제8권12호
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• pp.1061-1065
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• 2002

Sensors need to be implanted to obtain necessary information for LVAS (Left Ventricular Assist System) operations. Size of the sensors can prevent them from being implanted in a patient and reliabilities of the sensors are questionable for a long term use. In this wort we utilize a developed pump model to estimate flow and pressure difference across the pump without implanted sensors and present a method to obtain the physiological variables as aorta pressure and left ventricle pressure from the pump model and pulsatility of flow estimate or pressure difference estimate. These estimated variables can be used for LVAS control as an index or indices.

• Journal of Nutrition and Health
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• 제37권7호
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• pp.509-514
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• 2004

This study was conducted to investigate the supplementary effects of Lentinus edodes on blood pressure and blood lipid levels in the Hypertensive Rat. We supplied 3 kinds of experimental diets (Control; CO, cap of Lentinus edodes; LC, and stipe of Lentinus edodes; LS) to spontaneously hypertensive rats (SHR) for 8 weeks. Diet intake, body weight, organ weights, and serum lipid levels were measured. There was no significant difference in diet intake, and body, liver and epididymal fat pad weights among experimental groups. The levels of systolic and diastolic blood pressure were significantly lower in LC and LS groups than CO group. The concentrations of serum total cholesterol were lower in LC and LS groups than CO group. These results suggested that Lentinus edodes decrease blood pressure levels and serum total cholesterol concentration in the spontaneously hypertensive rats. But these effects of Lentinus edodes didn't show any significant difference between animals fed cap and stipe of this mushroom.

• 한국초전도ㆍ저온공학회논문지
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• 제2권1호
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• pp.45-50
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• 2000

The present study has been conducted to observe the heat transfer under pulsating pressure and oscillating flow. The experimental apparatus was fabricated to measure the gas temperature, the wall temperature. the pressure and the instantaneous heat flux inside the pulse tube. The measured gas temperature and heat flux must be calibarated to compensate their finite time constant in the oscillating flow conditious. The experiment was performed from 1 Hz to 5 Hz. The phase difference between the instantaneous heat flux and the gas-wall temperature difference was clearly observed. The experimental heat fluxes were compared to the theroretical correlations such as Complex Nusselt Number Model(CNNM) and Variable Coefficient Model(CVM). The heat flux predisted by CNNM was always greater than that of VCM. The experiment confirmed the valisity of the VCM for the instantaneous heat flux under the pulsating pressure and oscillating flow in the warm end of the pulse tube.

• 한국공작기계학회논문집
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• 제11권5호
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• pp.30-37
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• 2002

Single flighted screw injection technology is the most cost effective method for the production of film, sheet, pipe and the fundamental step in other processes including blow molding and injection molding. The temperature of polymer melts and injection pressure play a very important role in the injection molding machine. Thermal distortion and displacement of a screw by temperature difference and injection pressure difference ratio cause a friction and thermoelastic wear by metal-to-metal contact between the screw and the cylinder. In this paper we analyzed thermal distortions of a screw as functions of temperature distribution and pressure profiles by finite element analysis.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.247-250
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• 2008

급기가압은 건물의 중요 부분인 피난로 공간에 공기 압력을 상승시켜 피난자와 소방관에게 연기에 의해 영향을 받지 않는 보호된 피난로(계단과 로비)를 확보하는 방법이다. 본 연구에서, 급기가압을 평가하기 위해, 창문, 방화문과 급기댐퍼에 따른 건물의 구성 요소인 방(거실), 로비(전실), 풍도에서의 압력 특성을 연구하였으며, 실험변수에 대한 중요한 정보를 얻을 수 있었다.

• 대한조선학회논문집
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• 제41권4호
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• pp.17-29
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• 2004

Internal waves are computed using a ghost fluid method on an unstructured grid. Discontinuities in density and dynamic pressure are captured in one cell without smearing or oscillations along a multimaterial interface. A time-accurate incompressible Navier-Stokes/Euler solver is developed based on a three-point backward difference formula for the physical time marching. Artificial compressibility is introduced with respect to pseudotime and an implicit method is used for the pseudotime iteration. To track evolution of an interface, a level set function is coupled with the governing equations. Roe's flux difference splitting method is used to calculate numerical fluxes of the coupled equations. To get higher order accuracy, dependent variables are reconstructed based on gradients which are calculated using Gauss theorem. For each edge crossing an interface, dynamic pressure is assigned for a ghost node to enforce the continuity of total pressure along the interface. Solitary internal waves are computed and the results are compared with other computational and experimental results.

• 대한화학회지
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• 제28권1호
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• pp.14-19
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• 1984

메트미오글로빈의 압력에 의한 변성의 $H_2O$와 $D_2O$에서의 차이를 pH 5.7과 pH 7.0에서 연구하였다. 메트미오글로빈은 $D_2O$에서 $H_2O$보다 더 작은 압력에서 변성하였다. 그 차이가 pH 5.7에서가 pH 7에서 보다 더 컸다. $H_2O$와 $D_2O$에서 이 안정도의 차이가 단백질에 대한 $H^+$와 $D^+$의 결합에 차이가 있기 때문이며 또한, 수소가 중수소로 바뀜에 따르는 구조 변화 때문인 것으로 사료된다.

• 한국식품조리과학회지
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• 제11권5호
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• pp.527-535
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• 1995

현미밥의 취반조건이 맛에 미치는 영향을 알아보기 위해 가수량과 취반기구를 달리한 현미밥의 형태변화와 관능적, 기계적 특성 변화를 알아보았다. X-선 회절도로부터 Peak높이가 멥쌀밥보다 찹쌀밥이 낮았고, 가수량이 증가함에 따라 압력밥솥을 사용하였을때가 감소하였으며, 이는 SEM으로 관찰하였을 때에도 붕괴정도가 현저하게 보였다. 가수량을 달리하여 멥쌀현미와 찹쌀현미를 전기밥솥으로 취반한 결과 1.4배의 멥쌀현미밥과 1.2배의 찹쌀현미밥이 관능검사 결과 전체적인 선호도가 가장 높았으며 가수량이 증가할수록 수분함량과 수분활성도가 증가하였다. 가수량이 증가하면 텍스쳐 특성치의 차이가 커서 견고성, 탄성, 껌성 , 응집성 , 씹힘성은 감소하였고 조리기구에 따른 차이는 전기밥솥으로 취반한 경우가 압력밥솥으로 취반한 경우보다 견고성 , 응집성, 탄성, 껌성 및 씹힘성의 모든 특성값이 더 낮았다.

• 패션비즈니스
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• 제25권1호
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• pp.39-50
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• 2021

The purpose of this study was to investigate how wearing calf support and applying of electronic muscle simulation(EMS) affected the ability to balance. In this study, the one leg standing test for static balance and the Y balance test for dynamic balance were used to assess balance. At this time, the pressure of the calf support was different to produce two supporters, and a difference between wearing the support before, after, and after applying EMS was evaluated. Seven men in their 20s with healthy bodies were measured five times each with a five-minute break, taking into account muscle fatigue, and the difference between each variable was analyzed through a follow-up test using nonparametric statistical analysis. Studies have shown more difference from supporter B with a more appropriate pressure (mmgh) for increasing balance capability than from supporter A. In addition, it was confirmed that the use of EMS electrostimulation and support before measuring the balance capability resulted in a greater difference. The proper pressure (mmgh) supporters and EMS can increase the ability to balance, and these results can be expected to improve the balance ability of ordinary people in their daily lives.

• 한국융합학회논문지
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• 제8권9호
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• pp.357-364
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• 2017

본 연구의 목적은 뇌졸중 환자의 허리안정화운동이 들숨 및 날숨 압력에 미치는 시기별 변화를 알아보고자 하였다. 뇌졸중 환자 36명을 각각 허리안정화운동군 17명과 일반적 물리치료운동군 19명으로 나누어 중재를 실시하였다. 두 군 모두 호흡압력 측정기를 이용한 들숨 및 날숨 압력을 운동전, 4주와 8주에 걸쳐 측정하였다. 최대날숨압력에서 허리안정화운동군은 시기에 따라 운동전, 4주, 8주 모두에서 유의한 증가를 보였으나 일반적 물리치료 운동군은 모든 시기에서 유의한 차이가 없었다. 최대들숨압력에서 허리안정화운동군은 시기에 따라 운동전보다 4주, 4주보다 8주는 유의한 차이는 없었으나, 운동전보다 8주는 유의한 증가가 있었다. 일반적 물리치료운동군의 모든 시기에서 유의한 차이가 없었다. 두 군간 변화량 차이는 유의한 차이가 없었다. 본 연구를 통해 허리안정화운동이 뇌졸중 환자에 날숨압력 개선에 효과적인 것을 알 수 있었고, 이 운동을 지속적으로 한다면 들숨압력에도 효과적인 방법임을 확인할 수 있었다. 향후연구에서 허리안정화운동 후 개별적 호흡근육 측정이 연구되기를 기대한다.