• 한국전문물리치료학회지
• /
• 제20권4호
• /
• pp.55-64
• /
• 2013

The first purpose was to identify the plantar pressure distributions (peak pressure, pressure integral time, and contact area) during level walking, and stair ascent and descent in asymptomatic flexible flatfoot (AFF). The second purpose was to investigate whether peak pressure data during level walking could be used to predict peak pressure during stair walking by identifying correlations between the peak pressures of level walking and stair walking. Twenty young adult subjects (8 males and 12 females, age $21.0{\pm}1.7$ years) with AFF were recruited. A distance greater than 10 mm in a navicular drop test was defined as flexible flatfoot. Each subject performed at least 10 steps during level walking, and stair ascent and descent. The plantar pressure distribution was measured in nine foot regions using a pressure measurement system. A two-way repeated analysis of variance was conducted to examine the differences in the three dependent variables with two within-subject factors (activity type and foot region). Linear regression analysis was conducted to predict peak pressure during stair walking using the peak pressure in the metatarsal regions during level walking. Significant interaction effects were observed between activity type and foot region for peak pressure (F=9.508, p<.001), pressure time integral (F=5.912, p=.003), and contact area (F=15.510, p<.001). The regression equations predicting peak pressure during stair walking accounted for variance in the range of 25.7% and 65.8%. The findings indicate that plantar pressures in AFF were influenced by both activity type and foot region. Furthermore the findings suggest that peak pressure data during level walking could be used to predict the peak pressure data during stair walking. These data collected for AFF can be useful for evaluating gait patterns and for predicting pressure data of flexible flatfoot subjects who have difficulty performing activities such as stair walking. Further studies should investigate plantar pressure distribution during various functional activities in symptomatic flexible flatfoot, and consider other predictors for regression analysis.

• Journal of the korean society of oceanography
• /
• 제32권4호
• /
• pp.171-180
• /
• 1997

Daily mean sea level variability and its response to atmospheric pressure along the coasts of the northwestern Pacific Ocean are investigated. Daily values of sea level and atmospheric pressure covering the period 1976-1986 from 72 stations are analyzed. The sea level and the air pressure in all the data set have a definite seasonal signal, and higher frequency oscillations at time scales of several days to several weeks are also observed. Among the short-period oscillations of sea level with periods shorter than six months, the period of around 3 or 4 months is dominant in most study stations. According to the statistical analysis of sea level and air pressure, the length scale of sea level variability is smaller than that of air pressure for the present study area. The overall variability of sea level is found to be the smallest around Hokkaido, Japan and the largest in the China coasts. Large short-period (< 6 months) sea level variability is found in the southern coasts of China and Hokkaido, and large long-period (> 6 months) variability in the southern coasts of Japan and Korea along Tsushima Current and Kuroshio. The patterns of air pressure are very similar to those of sea level. The air pressure field is found to account for 31% of the overall sea level variability in the study area. Conside.ins the fact that the results (40%) of Pang and Oh (1995) were obtained through monthly sea level, the present result implies that the short-period sea level variability is less affected by air pressure. Generally the sea level response to air pressure are found to be isostatic, but significantly nonisostatic for the periods around 4 months and for those of 2 to 4 days. In particular, nonisostatic response for higher frequencies seem to be due to the restrictions to water transport necessary for barometric responsein the Korea Strait.

• 무역학회지
• /
• 제45권3호
• /
• pp.91-117
• /
• 2020

This study aimed to understand the relationships among the institutional pressure and the level of compliance and corporate value. The research focuses on four main variables, which are regulatory pressure, normative pressure, and cultural-cognitive pressure as the institutional pressure, and the CSR score as the level of the firm's compliance. We examined the impact of the institutional pressure on the firm's compliance-level, together with the effect of compliance level on the corporate value. We analyzed the 3,792 CSR data listed in China's A market and 31 province and city-level data from China. Results showed that institutional pressure had a positive influence on the firm's compliance level. The corporate value was greater with a high compliance level when the institutional pressure was high. The firm's compliance level negatively influenced corporate value when the institutional pressure was low. This study took into account a level of institutional pressures in three dimensions when investigating the effect of CSR compliance level on the corporate value. Thus, this study has a unique academic contribution by demonstrating that CSR activities can have a positive or negative effect depending on the institutional environment for each firm. The findings of this study also provide valuable insights to industry practitioners by suggesting the importance of considering the institution-specific condition when deciding to comply with the institutional pressure.

• 한국소음진동공학회논문집
• /
• 제24권4호
• /
• pp.339-347
• /
• 2014

Floor impact sound in high-rise apartment building became one of social problems. A lot of civil complaints on floor impact sound occur continuously and the number of disputes between neighbors in small and aged apartment buildings is increasing. Interests on heavy-weight impact sound pressure level measurement and evaluation method is increased. Previous study reported that heavy-weight impact sound level was changed by the sound field condition of receiving reverberation chamber. In this study, heavy-weight impact sound pressure level change by the receiving sound field condition was measured in standard test facility and mock-up test room. These two experimental conditions were designed to simulate averaged living room of common apartment units. By the change of sound absorption power in receiving room, heavy-weight impact sound pressure level in most of frequency bands were changed in standard test facility and mock-up room. Normalized maximum sound pressure level regulated in ISO 16032 showed wider range of heavy/soft impact sound pressure level. Heavy/soft impact sound pressure level change was became smaller by the application of standardized maximum sound pressure level and ISO/CD 10140-3 Amd 2 method. In the case of standardized maximum sound pressure level, absolute sound pressure level changed. From these results, receiving sound field correction method regulated in ISO/CD 10140-3 Amd 2 is needed for the precision measurement and evaluation of heavy-weight impact sound.

• 유체기계공업학회:학술대회논문집
• /
• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
• /
• pp.226-235
• /
• 2000

Two representative finite volume methods, i.e., the time marching method and the pressure correction method, were applied to 8 centrifugal compressor impeller flows, with low to very high level of pressure ratio, among which 7 impellers' experimental performance is given in the open literature. The present study is focused on the prediction differences from both methods, developed by the authors, in the pressure correction method's point of view. In all cases, the time marching method gives a satifactory solution, but the pressure correction method does not. Up to about $18\%$ less level of total-to-total pressure ratio is predicted by the pressure correction method as the level of the impeller pressure ratio increases up to about 10. The drop of total pressure ratio is caused by the underestimation of static pressure rise which seems to be attributed to inappropriate linearization and discretization of the pressure/density coupling terms in the pressure correction equation.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2001년도 춘계학술대회논문집
• /
• pp.1156-1161
• /
• 2001

A significant trial has been performed for estimation of noise level of a cross flow fan for air conditioning system. In general, measurements of noise level of machinery require rigorous equipment involving an anechoic chamber with precision gauges. The apparatus is expensive to utilize and is not easy to construct. In this work, we adopt static pressure sensing from an ordinary pressure transducer for prediction of noise level of a rotating fan. The present procedure is finding sound pressure from the static pressure by manipulating Light-Curle equation depicts noisy energy in terms of pressure on surfaces of noise generators. Sound power level near core unit of the fan is evaluated with the present methodology in a normal laboratory room without any sound absorbers. The method is easy and shows good prediction results compared with precise measurements by using microphones.

• 동력기계공학회지
• /
• 제13권4호
• /
• pp.31-37
• /
• 2009

The purpose of this numerical study was to investigate performance characteristics for cooling tower axial fans with sweep. Performance data for the fans with various sweep angles were obtained in terms of the setting angle at a constant flow rate. Viscous flow calculations were carried out to obtain Performance data of the total pressure rise and hydraulic efficiency. A solution of the Ffowcs Williams-Hawkings equations was used to calculate the sound pressure level at three times fan diameter away from the fan. The calculated performance data well represented performance characteristics of the cooling tower axial fan. The total pressure rise and hydraulic efficiency at the same setting angle decreased with sweep angle. Sound pressure level slightly decreased for the fan with a sweep angle of 10 degree. No significant effect of the sweep geometry was found on the sound pressure level.

• 한국축산식품학회지
• /
• 제27권2호
• /
• pp.190-196
• /
• 2007

본 실험은 압력 수준에 따른 PAF이 돈육의 이화학적 특성에 미치는 효과를 규명하고자 시도되었다. 비록 가압 수준기 증가에 따른 상전이 온도와 냉각온도간의 차이 감소에 기인하여 고압 하에서의 잠열 감소에 의한 동결 속도 증가의 효과는 얻을 수 없었지만, 육의 PAE 처리는 가압처리에서와 같이 보수력 및 육즙 손실을 대기압 동결 처리보다 더욱 현저하게 줄일 수 있었다. 그러나 지나친 가압은 육 단백질간의 aggregation 및 심한 변성에 기인하여 육의 연도를 저하시키는 결과를 초래하였고, 또한 소비자의 구매와 직접적으로 관련된 색도에 악영향을 끼친 것으로 판단되었다. 그러나 상대적으로 낮은 압력 범위 조건에서의 PAF 처리는 동결 시 고압 처리에 의한 육색 저하를 최소화 할 수 있었고, 전단력 측면에서도 대기압 동결처리와 유의적인 차이를 보이지 않을 뿐만 아니라 보수력을 향상시킴으로써 동결처리보다 더 큰 잠재적인 이점을 보였고, 이 부분에 대한 더 많은 연구가 필요할 것으로 판단된다.

• 성인간호학회지
• /
• 제12권4호
• /
• pp.619-628
• /
• 2000

The purpose of this study was to evaluate the knowledge level of pressure ulcer among hospital nurses through a cross-sectional survey by using the pressure ulcer knowledge assessment tool of Beitz et al.(1998). The total of subjects was 160 voluntary participants (60 were from Hospital A and 100 were from Hospital B) working at adult patients' units in two university hospitals located in the same city. None of the hospitals had expert nurses of pressure ulcer nor provided a regular pressure ulcer education program during the past one year. The survey tool consisted of 32 true-false items which were grouped into the risk factors knowledge category(13 items), the wound assessment knowledge category(4 items), and the treatment methods knowledge category(15 items). An internal consistency reliability test of the tool yielded an overall coefficient of 0.72; the coefficient for the risk factors knowledge category was 0.40, that for the wound assessment knowledge category was 0.33; that for the treatment knowledge category was 0.54. The main findings of the study are as follows. 1) Demographic characteristics of the two hospital nurses were similar except for the educational level(p=0.029) and the work units(p=0.001). These observations were maintained even if Hospital A and B were separately compared. 2) The knowledge level of the subjects about pressure ulcer in general was low as indicated by 53.3 points(of 100 possible points) on average. The knowledge level about treatment methods of pressure ulcer was the lowest as indicated by 47.0 points on average. 3) No correlation between the knowledge level of the pressure ulcer and the demographic characteristics of nurses was found except that the knowledge level of I.C.U. nurses was significantly higher(p=0.0003) than that of nurses in other units(p=0.2926) in the case of Hospital A. 4) The knowledge level of nurses in Hospital B was higher than for nurses in Hospital A. The reason was not identified, but it seems that it is related to the role of the I.C.U. or some other factors. The study results confirmed the existing literature that knowledge level of nurses about pressure ulcer is low regardless of age, educational level, or work experience. However, the working place(unit) affected the knowledge level. Further research on the exact reason for the differences in the knowledge level is needed in the future.

• 한국소음진동공학회논문집
• /
• 제23권3호
• /
• pp.274-281
• /
• 2013

Field measurement method of heavy/soft impact sound pressure level which is regulated in JIS and ISO has been using in Korea, Japan and Canada. It is reported that heavy/soft impact sound pressure level was varied by the sound field condition of receiving room such as sound absorption power and room volume. In this study, it is checked that heavy/soft impact sound pressure level was affected by the receiving sound field condition. Rubber ball and bang machine sound pressure level was measured in the vertically connected reverberation chamber. In oder to check the effect of receiving sound field on heavy/soft impact sound pressure, sound absorption power was changed with polyester sound absorption blankets with air space and glass wool. The reverberation time at 1 kHz band was changed from 10 s to 0.2 s by sound absorption material. Rubber ball sound pressure level measured without sound absorption material was 58 dB in $L_{i,Fmax,AW}$, but the level was 46 dB with sound absorption treatment. From this result, it is confirmed that sound field correction method is needed in the heavy/soft impact sound pressure level measurement method using bang machine and rubber ball.