• 한국강구조학회 논문집
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• 제21권3호
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• pp.289-299
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• 2009

본 연구는 각주형 저층건축물에 작용하는 지점별 풍압을 다점동시측정시스템을 이용하여 건물 폭과 깊이변화에 따른 평균풍압분포 특성에 대한 기초적인 결과를 정리한 것이다. 본 실험에서는 건물의 폭과 깊이를 변화시킨 5개의 각주형 풍압실험모형이 사용되었으며, 풍동실험은 금오공과대학교 소재 토출식 경계층풍동에서 실시하였다. 실험결과는 저층건축물의 건물 폭 및 깊이의 변화에 따른 저층건축물의 평균풍압분포 변화경향을 건축물의 풍상면, 풍측면 및 풍하면 중심으로 특성을 분석하였다. 실험결과를 토대로 저층건축물의 구조골조 설계용 풍하중을 합리적으로 산정하기 위해 필요한 새로운 풍압계수 및 간략한 약산식을 제시하였다.

• 한국산학기술학회논문지
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• 제10권8호
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• pp.1926-1938
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• 2009

본 연구에서는 혈압 측정 시 생체 임피던스가 변화하는 현상을 이용하여 혈류량 변화를 검출하는 시스템을 구현하였다. 혈압의 측정은 오실로메트릭법을 적용하였으며, MAA 알고리즘을 이용하여 평균 동맥압을 산출한 후 평균 동맥압에 대한 여러 가지 특성비율을 설정하여 수축기 및 이완기 혈압을 추정하였다. 인체 임피던스 측정은 교류 정전류원과 락인-증폭기를 이용하였으며, 측정 부위에 인가되는 커프 압력에 의해 생체 임피던스 변화량을 이용하여 혈류량 변화를 측정하였다.

• 한국자동차공학회논문집
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• 제17권2호
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• pp.118-125
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• 2009

Calculation of indicated mean effective pressure(IMEP) requires high cylinder pressure sampling rate and heavy computational load. Because of that, it is difficult to implement in a conventional electronic control unit. In this paper, a cylinder pressure based real-time IMEP estimation method is proposed for controller implementation. Crank angle at 10-bar difference pressure($CA_{DP10}$) and cylinder pressure difference between $60^{\circ}$ ATDC and $60^{\circ}$ BTDC($DP_{deg}$) are used for IMEP estimation. These pressure variables can represent effectively start of combustion(SOC) and fuel injection quantity respectively. The proposed IMEP estimation method is validated by transient engine operation using a common-rail direct injection diesel engine.

• 전기학회논문지
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• 제57권6호
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• pp.1095-1101
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• 2008

The desirable method to diagnose abnormal blood pressure is to measure and manage blood pressure continuously and regularly. However, the sphygmomanometers that are based on a cuff have faults in that they can not measure the blood pressure continuously and they cause an unpleasant feeling. Therefore, it is essential to develop a new measuring method that causes no pain and that can obtain blood pressure continuously without any unpleasant feeling. Thus, we propose here a regression method to estimate the systolic blood pressure by using the PTTL(pulse transit time on leg) with some body parameters which are chosen from the relational analysis with systolic blood pressure. The data we use to make the regression model were obtained in triplicate from each of 50 males who were from 18 to 35 years. And we made estimation experiments of blood pressure on 10 males who did not take part in the making the regression model. According to the results, the proposed method showed a mean error of 4.00 mmHg and the standard variance was 2.45 mmHg. When we comparing the results of the proposed method with the rule of American National Standards Institute of the Association of the Advancement of Medical Instruments(ANSI/AAMI), the results satisfied the rule of a mean error less than 5 mmHg and a standard variance less than 8 mmHg. Therefore we were able to validate the usefulness of the proposed method.

• 한국연소학회지
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• 제14권4호
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• pp.41-47
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• 2009

An experimental study was performed to confirm the effect of the changing combustor pressure(-30~30 kpa), combustion characteristics were investigated by measuring the local chemiluminescence intensity, the local temperature distribution and emission. In order to investigate combustion ones, the combustor pressure index($P^*$) was controlled in the range of 0.7~1.3 for each equivalence ratio in the present combustion system, where $P^*$ is defined as the ratio of absolute pressure to atmospheric one. The local mean temperature showed the uniform distributions for lower pressure index, which increased with increasing equivalence ratio. The mean $OH^*$ chemiluminescence intensity, showed high level for lower pressure index for ${\Phi}{\get}1.0$ conditions. EINOx decreased with decreasing pressure index for overall equivalence ratio conditions.

• 한국한의학연구원논문집
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• 제18권3호
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• pp.111-118
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• 2012

Objective : The aim of this study was to investigate the number of measurements and visits for blood pressure measurement. We also analyzed the change of blood pressure based on the measurement method and measurement interval. Methods : Data of three clinical trials evaluating the effect of acupuncture, moxibustion, and qigong for pre and mild essential hypertension were used. Blood pressure was measured 3 times each visit with 1 or 5 minutes interval, and it was checked until $3^{rd}$ visit. Two trials used sphygmomanometer and another one trial used automatic device for blood pressure measurement. Results : The mean difference between $1^{st}$ and $2^{nd}$, and $2^{nd}$ and $3^{rd}$ measurement were significant in systolic (p<0.001) and diastolic blood pressure (p<0.001). However, in automated measurement or measuring with 1 minute interval, the difference between $2^{nd}$ and $3^{rd}$ was not significant. The mean of $1^{st}$ and $2^{nd}$ measurements was also significantly different from the mean of all three measurements in both systolic (p<0.001) and diastolic blood pressure (p<0.001). While the difference between each visit was not significant in diastolic blood pressure, the systolic blood pressure difference was significant between $1^{st}$ and $2^{nd}$ visit in automated and manual measurement. Conclusion : The mean of two measurements and three measurements were significantly different. The change of blood pressure was different according to the method and interval of blood pressure measurement.

• 대한예방한의학회지
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• 제5권2호
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• pp.29-39
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• 2001

Purpose: This study was conducted to investigate and compare the growth, blood pressure, and s-cholesterol of urban and rural students in Korea. Methods: April 1999, We examined the students' health of a boys high school and a girls high school in a urban area - Jeonju, Korea.(boys were 317, girls were 343). And we also examined the students' health of a high school in a rural area - Gimje, Korea.(boys were 33, girls wee 36). Height, body-weight, Body Mass Index(BMI)I, blood pressure, and s-cholesterole were checked and compared between two groups. Results and Conclusion: The mean of height in urban students was $165.25{\pm}7.79cm$, and that in rural students was $163.77{\pm}8.72cm$. There was no significant difference stastically between two groups. The mean of body-weight in urban students $(57.78{\pm}10.51kg)$ was significantly higher than that in rural students $(54.71{\pm}10.11kg)$)(p<0.05). The mean of body mass index(BMI) in urban students $(21.12{\pm}3.27kg/m2)$ was significantly higher than that in rural students $(20.30{\pm}2.69kg/m2)$(p<0.05). Obese students $(BMI{\geq}27)$ were 31(4.70%) in urban students, 3(4.35%) in rural students. The mean of systolic blood pressure in rural students $(114.99{\pm}9.50mmHg)$ was significantly higher than that in urban students $(111.89{\pm}12.42mmHg)$(p<0.05) The mean of diastolic blood pressure in rural students$(75.72{\pm}9.90mmHg)$ was very significantly higher than that of urban students $(68.45{\pm}9.40mmHg)$(p<0.001). Hypertensives (${\geq}138/86mmHg\;in\;boys,\;{\geq}130/83mmHg$ in girls) were 28(4.24%) in urban students, 13(18.84%) in rural students. The mean of s-cholesterol in urban students was $174.95{\pm}32.28mg/dL$, and that in rural students was $176.81{\pm}33.18mg/dL$. There was no significant difference stastically between two groups. Hypercholesterolemias (${\geq}198mg/dL$ in boys, ${\geq}212mg/dL$ in girls) were 130(19.70%) in urban students, 14(20.89%) in rural students. These results suggest that there are differences in body weight, BMI, and diastolic blood pressure between urban and rural students and that it is necessary to consider these differences in health examination.

• 한국운동역학회지
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• 제26권1호
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• pp.115-126
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• 2016

Objective: The purpose of this study was to investigate plantar foot pressure and static balance according to the type of insole in the elderly. Methods: Thirteen elderly (mean age: $67.08{\pm}2.25years$, mean height: $159.63{\pm}9.64cm$, mean body weight: $61.48{\pm}9.06kg$) who had no previous injury experience in the lower limbs and a normal gait pattern participated in this study. Three models of insoles of the normal, 3D, and triangle types were selected for the test. The Pedar-X system and Pedar-X insoles, 3.3 km/h of walking speed, and a compilation of 20 steps walking stages were used to analyze foot-pressure distribution. Static balance test was conducted using Gaitview AFA-50, and balance (opening eyes, closing eyes) was inspected for 20 s. One-way ANOVA was conducted to test the significance of the results with the three insoles. p-value of less than .05 was considered statistically significant. Results: The mean foot pressure under the forefoot regions was the lowest with the 3D insole during treadmill walking (p<.05). The mean value under the midfoot was the highest with the 3D insole (left: p<.05, right: p<.01). The mean value under the rearfoot was the lowest with the 3D insole (p<.001). The maximum foot pressure value under the foot regions was the lowest on both sides of the forefoot with the 3D insole. A statistically significant difference was seen only in the left foot (p<.01). The maximum value under the midfoot was the highest with the 3D insole (p<.001). No statistically significant difference was detected on the values under the rearfoot. In the case of vertical ground reaction force (GRF), statistically significant difference was seen only in the left side rearfoot (p<.01). However, static balance values (ENV, REC, RMS, Total Length, Sway velocity, and Length/ENV) did not show significant differences by the type of insole. Conclusion: These results show that functional insoles can decrease plantar pressure and GRF under the forefoot and rearfoot. Moreover, functional insoles can dislodge the overload of the rearfoot and forefoot to the midfoot. However, functional insoles do not affect the static balance in the elderly.

• 대한한방소아과학회지
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• 제15권1호
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• pp.117-129
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• 2001

Objective : Hyperlipidemia and hypertension are well recognized risk factors of cerebrovascular disease. So it's very important to evaluate blood pressure and s-cholesterol in adolescence. Material and Methods : April 1999, we were requested health examinaion for high school students of a boys high school and a girls high school in Jeonbuk, Korea. The subjects were 360 students, boys were 317 and girls were 343. They were checked their height, body weight, blood pressure, and s-cholesterol. Results and Conclusion : The mean of systolic blood pressure of study subjects was $111.89{\pm}12.43mmHg$. In boys, it was $116.25{\pm}11.78mmHg$, and in girls, it was $107.87{\pm}11.64mmHg$. The mean of diastolic blood pressure of study subjects was $68.45{\pm}9.40mmHg$. In boys, it was $66.92{\pm}10.00mmHg$, and in girls it was $69.85{\pm}9.40mmHg$. Hypertensives were 18(5.68%) in boys, 10(2.92%) in girls. The mean of s-cholesterol of study subjects was $174.95{\pm}32.28mg/dL$. In boys, it was $178.91{\pm}34.51mg/dL$, and in girls, it was $171.29{\pm}29.66mg/dL$. Hypercholesterolemias were 91(28.71%) in boys, 39(11.37%) in girls. The mean of BMI of study subjects was $21.12{\pm}3.27kg/m2$. In boys, it was $21.05{\pm}3.26kg/m2$, and in girls, it was $21.18{\pm}3.29kg/m2$. Obese boys were 18(5.68%), obese girls were 13(3.79%). The mean of diastolic blood pressure in obese boys was significantly higher than that of normal boys(p=0.001, Mann-Whitney test). The mean of s-cholesterol in obese boys($BMI{\ge}274$) was significantly higher than that of normal boys.(P=0.26, Mann-Whitney test).

• Wind and Structures
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• 제4권5호
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• pp.399-412
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• 2001

Simultaneous pressure and force measurements have been conducted on a stationary box deck section model for two configurations (namely without and with New Jersey traffic barriers) at various angles of incidence. The mean and fluctuating aerodynamic coefficients and pressure coefficients were derived, together with their spectra and with the coherence functions between the pressures and the total aerodynamic forces. The mean aerodynamic coefficients derived from force measurements are first compared with those derived from the integration of the pressures on the deck surface. Correlation between forces and local pressures are determined in order to gain insight on the wind excitation mechanism. The influence of the angle of incidence on the pressure distribution and on the fluctuating forces is also analysed. It is evidenced how particular deck section areas are more responsible for the aerodynamic excitation of the deck.