• 제목/요약/키워드: Body Pressure

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다물체계내 유연체의 구조기인 소음해석 (Structure Borne Noise Analysis of a Flexible Body in Multibody System)

  • 김효식
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.130-135
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    • 2003
  • This paper presents the method for structure borne noise analysis of a flexible body in multibody system. The proposed method is the superposition method using flexible muitibody dynamic analysis and finite element one. This method is executed in 3 steps. In the la step, time dependent quantities such as dynamic loads, modal coordinates ana gross body motion of the flexible body are calculated efficiently through flexible multibody dynamic analysis. And frequency response functions are computed using Fourier transforms of those time dependent quantities. In the 2$\^$nd/ step, acoustic pressure coefficients are obtained through structure-acoustic coupling analysis by finite element analysis. In the final step, frequency responses of acoustic pressure at the acoustic nodes are recovered through linear superposition of frequency response functions with acoustic pressure coefficients. The accuracy of the proposed method is verified in the numerical example of a simple car model.

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수소 충전소용 초고압 볼밸브 설계에 관한 연구 (A Study on Design of Ultra-High-Pressure Ball Valve for Hydrogen Station)

  • 최지아;지상원;장지성
    • 드라이브 ㆍ 컨트롤
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    • 제18권3호
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    • pp.23-29
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    • 2021
  • Hydrogen energy is the clean energy source of the future. Ultra-high-pressure hydrogen is used in hydrogen stations, with its parts being developed. On the other hand, ultra-high-pressure ball valve, which is one of its parts, depends on overseas, with the level of domestic research on this being only about 10% of advanced technology research on this abroad. In this study, the shape of an ultra-high-pressure ball valve for a hydrogen station was designed to improve its structural strength. The valve body was designed according to distance between both processed body holes along inlet and outlet ports. The designed vale body was then analyzed using ANSYS to check whether points with stress were concentrated. In addition, the valve with improved body was analyzed to confirm that the valve satisfied the design condition.

체력관리 수업이 여자 대학생의 신체구성, 혈압 및 건강관련 체력에 미치는 영향 (The Effect of Fitness Management Class on Body Composition, Blood Pressure and Health-related Fitness in College Women)

  • 김명수;김성희;이신호
    • 디지털융복합연구
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    • 제14권12호
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    • pp.607-614
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    • 2016
  • 본 연구는 체력관리 수업이 비만도가 각기 다른 여자 대학생들의 신체구성, 혈압 및 건강관련 체력에 미치는 영향이 다른지에 대해 검증하는 것이다. 본 연구의 대상자는 본교 2012~2016년 9학기 동안 체력관리 수업을 수강한 여학생 317명을 대상으로 하였으며, 그룹 구분은 체질량지수와 체지방률(%) 기준으로 저체중, 마른 비만, 정상, 정상 비만 그리고 비만 그룹으로 구분하였다. 체력관리 수업은 저항성 운동과 유산소 운동의 복합운동으로 일일 75분, 주 2회로 구성하여 진행하였다. 본교의 체력관리 수업은 비만 그룹을 제외한 네 그룹의 체중, 체질량지수, 체지방율, 근육량 그리고 허리둘레를 긍정적으로 개선시키는 효과가 있는 것으로 나타났다. 하지만 혈압(SBP, DBP)과 건강관련 체력에서는 다섯 그룹 모두에서 대부분 긍정적으로 개선되는 효과가 있었다. 따라서 체력관리 수업은 비만 여자 대학생의 신체구성의 개선을 제외하고 여자 대학생들의 신체구성과 혈압의 개선 및 건강관련 체력을 향상시키는 것으로 나타났다.

탄성 압박 밴드를 이용한 인체 부위별 의복압 가압 수준에 관한 연구 (Determination of the Garment Pressure Level Using the Elastic Bands by Human Body Parts)

  • 백윤정;최정화
    • 한국의류학회지
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    • 제32권10호
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    • pp.1651-1658
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    • 2008
  • This study was to decided the proper garment pressure level on the human body parts. Six volunteers (female: 30-40years) put on the same types of bands, a brief, and a non-woven gown. Garment pressure was measured in regular order with the elastic band on the human body parts such as the upper arm, the waist, the thigh, and the calf. At the same time, physiological responses such as the skin blood flow rate on 2 fingers, 7 different skin temperatures, rectal temperature, heat rates, and subjective responses about the pressure sensation, thermal sensation, and humidity sensation were measured and inquired. The results were as follows; 1. The thicker subcutaneous fat thickness, the higher the mean garment pressure on pressurizing the upper arm(p<.001). Also the thicker subcutaneous fat thickness. the thicker the upper arm circumference. 2. Heart rates increased pressured the upper arm and decreased pressured the waist, the thigh, and the calf. The higher the garment pressure, the higher heart rates on all body parts were pressured. Especially lean subjects showed higher physiological load than others. 3. On pressurizing the upper arm, heart rates, rectal temperature, and mean skin temperature were higher than without pressured state and pressured other body parts.4. The proper garment pressure levels were decided 30gf/$cm^2$ for fat people, 20gf/$cm^2$ for others on the upper arms and 24gf/$cm^2$ on the calf.

The relationships of body mass index, waist-to-height ratio, and body fat percentage with blood pressure and its hemodynamic determinants in Korean adolescents: a school-based study

  • Kim, Na Young;Hong, Young Mi;Jung, Jo Won;Kim, Nam Su;Noh, Chung Il;Song, Young-Hwan
    • Clinical and Experimental Pediatrics
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    • 제56권12호
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    • pp.526-533
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    • 2013
  • Purpose: Obesity is an important risk factor for hypertension in adolescents. We investigated the relationship of obesity-related indices (body mass index [BMI], waist-to-height ratio [WHR], and body fat percentage [%BF]) with blood pressure and the hemodynamic determinants of blood pressure in Korean adolescents. Methods: In 2008, 565 adolescents, aged 12-16 years, were examined. The %BF of the participants was measured by bioelectrical impedance analysis. Echocardiography and brachial artery pulse tracing were used to estimate the stroke volume (SV), cardiac output (CO), total vascular resistance (TVR), and total arterial compliance (TAC). Results: We noted that BMI, WHR, and %BF were positively correlated with systolic blood pressure (SBP) and diastolic blood pressure (DBP). The positive correlation between BMI and blood pressure (SBP and DBP) persisted after adjustment for WHR and %BF. However, after adjustment for BMI, the positive associations between blood pressure (SBP and DBP) and WHR as well as %BF, were not noted. With regard to the hemodynamic factors, BMI, but not WHR and %BF, was an independent positive factor correlated with SV and CO. TVR had an independent negative association with BMI; however, it was not associated with WHR or %BF. Moreover, we noted that BMI, WHR, and %BF did not affect TAC. Conclusion: In Korean adolescents, BMI had an independent positive correlation with SBP and DBP, possibly because of its effects on SV, CO, and TVR. WHR and %BF are believed to indirectly affect SBP and DBP through changes in BMI.

The effect of low glycemic index diet on body weight status and blood pressure in overweight adolescent girls: a randomized clinical trial

  • Rouhani, Mohammad Hossein;Kelishadi, Roya;Hashemipour, Mahin;Esmaillzadeh, Ahmad;Azadbakht, Leila
    • Nutrition Research and Practice
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    • 제7권5호
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    • pp.385-392
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    • 2013
  • Although several studies have assessed the influence of the glycemic index on body weight and blood pressure among adults, limited evidence exists for the pediatric age population. In the current study, we compared the effects of low glycemic index (LGI) diet to the healthy nutritional recommendation (HNR)-based diet on obesity and blood pressure among adolescent girls in pubertal ages. This 10-week parallel randomized clinical trial comprised of 50 overweight or obese and sexually mature girls less than 18 years of age years, who were randomly assigned to LGI or HNR-based diet. Macronutrient distribution was equivalently prescribed in both groups. Blood pressure, weight and waist circumference were measured at baseline and after intervention. Of the 50 participants, 41 subjects (include 82%) completed the study. The GI of the diet in the LGI group was $42.67{\pm}0.067$. A within-group analysis illustrated that in comparison to the baseline values, the body weight and body mass index (not waist circumference and blood pressure) decreased significantly after the intervention in both groups (P = 0.0001). The percent changes of the body weight status, waist circumference and blood pressure were compared between the two groups and the findings did not show any difference between the LGI diet consumers and those in the HNR group. In comparison to the HNR, LGI diet could not change the weight and blood pressure following a 10-week intervention. Further longitudinal studies with a long-term follow up should be conducted in this regard.

세라믹소재를 이용한 해수압센서 제작 및 전기적 특성 연구 (A Study on the Fabrication and Electrical Characteristics of Hydraulic Pressure Sensors by Using Ceramics Materials)

  • 박성현;김은섭;정정균
    • 한국전기전자재료학회논문지
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    • 제28권6호
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    • pp.384-389
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    • 2015
  • In this paper, we fabricated ceramic body and sapphire wafer in order to develop a hydraulic pressure sensor with high sensitivity and high temperature stability. The sapphire wafer was adopted with a membrane of capacitance ceramic pressure sensor. The capacitance value of the sensor for the finite element analysis(FEM) showed a linear pressure characteristics. Membrane was processed with a diameter of 32.4 mm and a thickness of 1 mm by using alumina powders. Ceramic body was processed with a diameter 32.4 mm and a thickness 5 mm. The capacitance pressure sensor was made with high heat treatment of the ceramic body and the sapphire wafer. Initially capacitance of the pressure sensor was 50 pF and a capacitance of 110 pF was measured from 5 bar pressure. Output voltage of 5 V was appeared at 5 bar pressure.

중환자실 환자의 욕창 관련 경계압력 예측요인 (Factors Predicting the Interface Pressure Related to Pressure Injury in Intensive Care Unit Patients)

  • 신지선;김수진;이지현;유미
    • 대한간호학회지
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    • 제47권6호
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    • pp.794-805
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    • 2017
  • Purpose: Interface pressure is a factor that contributes to the occurrence of pressure injuries. This study aimed to investigate interface pressure at common sites of pressure injury (occipital, gluteal and peritrochanteric areas), to explore the relationships among risk factors, skin condition and interface pressure, and to identify risk factors influencing interface pressure. Methods: A total of 100 patients admitted to the intensive care unit were enrolled at a tertiary teaching hospital in Korea. Interface pressure was recorded by a scanning aid device (PalmQ). Patient data regarding age, pulmonary disease, Braden Scale score, body mass index, serum albumin, hemoglobin, mean blood pressure, body temperature, and oxygen saturation were included as risk factors. Data collected from July to September 2016 were analyzed using binary logistic regression. Results: The mean interface pressure of the occipital, gluteal, and right and left peritrochanteric areas were 37.96 (${\pm}14.90$), 41.15 (${\pm}16.04$), 53.44(${\pm}24.67$), and 54.33 (${\pm}22.80$) mmHg, respectively. Predictive factors for pressure injuries in the occipital area were age ${\geq}70$ years (OR 3.45, 95% confidence interval [CI]: 1.19~9.98), serum albumin deficit (OR 2.88, 95% CI: 1.00~8.26) and body temperature ${\geq}36.5^{\circ}C$ (OR 3.12, 95% CI: 1.17~8.17); age ${\geq}70$ years (OR 2.81, 95% CI: 1.10~7.15) in the right peritrochanteric area; and body temperature ${\geq}36.5^{\circ}C$ (OR 2.86, 95% CI: 1.17~6.98) in the left peritrochanteric area. Conclusion: Our findings suggest that old age, hypoalbuminemia, and high body temperature may be contributory factors to increasing interface pressure; therefore, careful assessment and nursing care of these patients are needed to prevent pressure injury. Further studies are needed to establish cutoff values of interface pressure for patients with pressure ulcers.

고등학교 야구선수들의 신체정렬과 족저압 분포 간의 상관관계 분석 (Correlation between body alignment and foot pressure in high School Baseball Players)

  • 박치복;정호진;박성환
    • 한국산학기술학회논문지
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    • 제20권12호
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    • pp.224-229
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    • 2019
  • 본 연구는 고등학교 야구선수를 대상으로 신체정렬과 족저압 분포 분석하여 올바른 자세지도와 스포츠 손상 및 부상 예방 프로그램에 참고 자료를 제공하는데 그 목적이 있다. 연구 대상자 32명을 대상으로 실시하였다. 신체정렬은 척추에서 몸통의 좌우기울기, 등뼈의 뒤굽음각, 허리뼈의 앞굽음각, 골반에서는 골반의 기울기, 골반의 뒤틀림을 측정하였고 족저압은 각 발의 좌우 체중분포, 각 발의 최대압력을 측정하였다. 측정항목에 대한 평균과 표준편차를 산출하여 도표화하였고, 신체정렬과 족저압 분포의 상관관계를 알아보기 위해 pearson's cerrelation analysis를 사용하여 분석하였다. 모든 통계학적 유의 수준은 0.05로 설정하였다. 신체정렬과 족저압 분포 간의 상관관계를 분석한 결과 척추에서 허리뼈의 앞굽음각과 좌우 최대압력에서 양의 상관관계가 나타났다. 몸통의 좌우기울기, 등뼈의 뒤굽음각, 골반의 기울기, 골반의 뒤틀림과 각 발의 좌우 체중분포, 각 발의 최대압력에서는 상관관계가 나타나지 않았다. 본 연구를 통해 허리뼈의 앞굽음각이 증가될수록 발의 한쪽에 힘이 더 실리게 되어 최대압력이 증가하는 양의 상관관계를 나타내는 것을 알 수 있었다. 향후 운동선수들의 신체정렬과 족저압 분포에 대한 운동프로그램의 참고 자료가 될 것으로 사료된다.