• 한국지반공학회논문집
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• 제20권8호
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• pp.193-203
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• 2004

표면이 거친 강성옹벽의 경우 뒷채움재에서 발생하는 아칭효과로 인해 옹벽에는 비선형의 토압분포가 작용하며, 아칭효과가 비선형의 토압분포에 미치는 영향은 옹벽의 변위 형태에 따라 달라진다. 따라서 강성옹벽에 작용하는 주동토압의 크기와 비선형의 토압분포를 정확하게 산정하기 위해서는 옹벽의 변위형태에 따라 달라지는 뒷채움재에 서 발생하는 실제적 인 파괴면 형상과 아칭효과를 고려해야만 한다. 따라서 본 연구에서는 강성옹벽이 저점을 중심으로 회전하는 경우에 뒷채움재에서의 아칭효과와 비선형의 파괴면 형상을 고려함으로써 비선형의 주동토압을 산정할 수 있는 토압산정식을 제안하였다. 이 과정에서 토압산정식이 수학적으로 복잡해지는 것을 피하기 위하여 뒷채움재에서 발생하는 비선형의 파괴면 형상은 4개의 직선으로 구성되는 가상의 파괴면으로 대체하였다. 그리고 제안식으로부터 구한 예측치를 기존의 모형시험 결과와 비교한 결과 제안식은 만족스런 토압 예측치를 제공하는 것으로 나타났다.

• 대한인간공학회지
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• 제26권2호
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• pp.157-165
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• 2007

The Work-Related Musculoskeletal Disorders (WMSDs) can be occurred by various factors such as repetition, forceful exertions and awkward postures. Especially, occurrences of the WMSDs on the waist and lower limb are reported in workplaces, demanded standing postures for a long time, in service and manufacturing industry. The static and standing postures without movement for a long time increase work loads to the lower limb and the waist. Accordingly, anti-fatigue mat or anti-fatigue insole is used as a preventing device of the WMSDs. However anti-fatigue mats are limited in space and movement. In this study, multi-elastic insoles are designed and shown the effects of the workload reduction for a long time under the standing work. The foot pressures and EMG (Electromyography) are measured at 0 hour and after 2 hours by 6 health students in their twenties. The 6 prototype insoles are designed with three elastic (Low, Medium and High). These insoles are compared with no insole (insole type 7) as control group. The EMG measurement was conducted to waist (erector spinae muscle), thigh (vastus lateralis muscle) and calf (gastrocnemius muscle). The foot pressure is analyzed by mean pressure value and the EMG analysis is investigated through MF (Median Frequency), MPF (Mean Power Frequency) and ZCR (Zero Crossing Rate). The results of the foot pressure show that the multi-elastic insoles had smaller foot pressure value than that of no-insole. Moreover, Insole 2 and Insole 3 have the smallest increasing rate in foot pressure. The EMG results show that the multi-elastic insoles had smaller EMG shift value than that of no-insole in 2 hour, and then shift value shows the smallest value in Insole 2. Therefore, this study presents that the multi-elastic insoles have reducing effects of the work load for a long time standing work in both side of foot pressure and EMG.

• 한국축산식품학회지
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• 제28권4호
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• pp.415-421
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• 2008

This study evaluated the effects of thermal processing combined with high pressure on the properties of cooked pork. Pressurization followed by heating (PFH), heating followed by pressurization (HFP) and heating under pressurization (HUP) treatments were compared to a heated only control. Cooked meat without simultaneous pressurization showed little or no decrease in water binding properties relative to the control, regardless of the sequence of pressurization and heating. However, HUP treated pork had significantly higher water binding properties than the control (p<0.05). The pH values of all treatments were not significantly different with the exception of HUP at 300 MPa. The HUP treated pork showed the best tenderizing effects among all the treatments tested and the effect was more significant at increased pressure levels (p<0.05). In addition, increasing pressure levels significantly increased the L-values of pork (p<0.05). PFH and HFP treated pork had significantly lower a-values (p<0.05), while no significant differences were observed in HUP. HUP treated pork had the lowest b-values at 100 MPa. however, the differences were not significant at increasing pressure levels. These results indicate that heating under pressure is the best cooking condition for improving the quality characteristics of pork without adversely affecting its appearance.

• International journal of advanced smart convergence
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• 제9권3호
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• pp.71-77
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• 2020

This study was conducted in order to determine how reductions in blood pressure during surgery affect intraoperative neuromonitoring. This retrospective study considered a total of 339 patients: 194 patients with normal neuromonitoring findings (57%), 145 (42%) with abnormal neuromonitoring findings, and 34 (10%) with postoperative neurological deficits. Comparisons between the three groups revealed that overall blood pressure during surgery, postoperative blood pressure, and the difference between the maximum and minimum blood pressure could affect the intraoperative neuromonitoring findings. While we indicate that a drop in blood pressure to below 70 mmHg could affect neuromonitoring results, differences in the dosage of anesthetic agents did not significantly affect reductions in blood pressure or neuromonitoring findings. The association of monitoring with blood pressure found in this study is expected to help future examiners. However, this study did not clarify the relationship between anesthesia and blood pressure and how it could affect intraoperative neuromonitoring. Therefore, further research on this part is thought to be necessary.

• 한국정밀공학회지
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• 제26권4호
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• pp.55-63
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• 2009

This paper reports on the theoretical and experimental study of the pressure ripples in a pressure unbalanced type vane pump which have widespread use in industry. Because they can infinitely vary the volume of the fluid pumped in the system by a control. Pressure ripples occur due to the flow ripples induced by geometry of side plate, leakage flow, reverse flow from the outlet volume produced by pressure difference between pumping chamber and outlet volume when the pumping chamber connected with the outlet volume. In this paper, we measured the pressure variation of a pumping chamber, reaction force on a cam ring, the mathematical model for analyzing the pressure ripples which included vane detachment and fluid inertia effects in notch area has been presented, and was applied to predict the level and the wave form of the pressure ripples according to operating conditions.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1993년도 춘계학술대회논문집
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• pp.145-145
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• 1993

In bicycle design, saddle is the major part which effects the subjective comfort of rider. This study examines the correlation between the subjective comfort and elastic body pressure. The elastic body pressure measuring instrument for free-form surface such as saddle is developed by force sensor register, A/D converter and computer. The subjective comfort is measured quantit- atively by 11-point scale method and the elastic body pressure distribution is obtained through 3 different saddles at 4 postures. The pressure distribution is presented by computerized equi- pressure contour. While mean pressure, standard deviation of pressure, maximum pressure are inversely proportional to subjective comfort, the modified saddle-bearing weight which is the surface integral of pressure is directly proportional. Consequently, standard deviation of pressure is most important characteristic which affects variation of subjective comfort.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.1381-1382
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• 2010

• 천문학회지
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• 제12권1호
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• pp.1-5
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• 1979

The usual assumption of the pressure equilibrium between the convective elements and the surrounding fluid has been dropped, and the effects of the pressure perturbation of the convective element on its velocity and T perturbation have been estimated.

• 한국콘텐츠학회논문지
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• 제15권1호
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• pp.462-474
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• 2015

본 연구는 소셜미디어 이용자를 대상으로 소셜미디어에 대한 이용자 동기가 이용자 몰입에 미치는 영향에 있어 소셜미디어에 대한 사회적 압력이 양자의 관계에서 어떠한 기능을 하는지 살펴보기 위하여 수행되었다. 이를 위해 소셜미디어 이용자 동기 차원을 각각 사회적 동기, 기능적 동기, 유희적 동기로 구분하였으며, 사회적 압력은 정보소외압력과 동조압력으로 구분하여, 각 차원에서 사회적 압력이 이용자 동기와 이용자 몰입의 관계에 있어 어떤 차별적 효과를 나타내는지를 확인하고자 하였다. 본 연구의 결과를 정리하면 다음과 같다. 첫째, 소셜미디어에 대한 이용자의 사회적 동기와 유희적 동기는 소셜미디어에 대한 이용자 몰입에 정적으로 유의미한 영향을 주는 것으로 나타났다. 둘째, 정보소외압력은 기능적 동기와 몰입 간의 관계에서 조절효과가 나타났다. 셋째, 동조압력은 사회적 동기와 몰입 간의 관계에서 조절효과가 발생하였다. 본 논문은 소셜미디어에 대한 이용과 몰입 현상에서 사회적 압력이 작용하는 방식에 대한 실증적 자료를 제시하였다는 점에서 의의가 있다. 그러나 소셜미디어와 관련된 사회적 압력에 대한 보다 세분화된 요인을 탐색하고 이들이 이용자 몰입에 미치는 영향에 대한 다각적인 연구가 진행될 필요성이 제기된다.

• 대한기계학회논문집B
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• 제40권10호
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• pp.645-651
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• 2016

본 연구에서는 압력면익단소익의 폭이 터빈 동익 압력면스퀼러팁 하류의 팁누설유동 및 압력손실에 미치는 영향에 대하여 연구하였다. 팁간극비 h/s = 1.36%에 대하여, 흡입면스퀼러의 높이는 $h_p/s=3.75%$로 일정하게 유지하고, 압력면익단소익의 폭은 w/p = 2.64%, 5.28%, 7.92%, 10.55% 등으로 변화시키면서 실험을 수행하였다. 일반적으로 압력면익단소익의 폭이 증가할수록, 통로와류 영역에서의 압력손실은 감소하였지만 팁누설유동 영역에서는 압력손실이 오히려 증가하였다. 그 결과 익단소익의 폭이 증가할수록, 질량평균 압력손실은 매우 소폭 감소하는 경향을 보였다. 본 연구 결과, 압력면스퀼러팁에 설치된 압력면익단소익은 압력손실 저감에 거의 기여를 하지 못함을 확인할 수 있었다.