• 제목/요약/키워드: third pressure

검색결과 642건 처리시간 0.022초

불활성 기체에 대한 열역학적 실험식 (Empirical Equations for Thermodynamic Physical Properties of Inert Gas)

  • 김재덕;여미순;이윤우;노경호
    • 한국화재소방학회논문지
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    • 제17권1호
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    • pp.26-32
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    • 2003
  • Halon대체 소화제로 쓰이는 불활성 기체 중 Ar, $N_2$, $CO_2$의 단일 성분일 때의 물성(포화압력, 밀도, 점도)에 관한 실험식을 구하였다. 문헌에서 얻은 실험 값을 이용하여 다항식 등의 회귀분석에 의해서 실험식을 얻었다. 포화압력은 온도에 대하여 각각 2차와 3차의 실험식으로 표시하였다. 밀도는 Ar, $N_2$는 온도에 대한 1차 함수로 표시하였고, $CO_2$는 온도에 대하여 각각 2차와 3차의 실험식으로 표시하였다. 점도는 온도에 대한 지수함수로 표시하였다. 이들 실험식을 이용하여 단일 성분일 때의 상태를 알 수 있다.

가족생활주기에 따른 교직주부의 시간제약지각이 시간제약대처전략에 미치는 영향 (The Influences of Family Life Cycle Stages and perceived Time Pressure on Strategies for Coping with Time Constraints in Hosuewife-Teachers)

  • 장윤옥
    • 가정과삶의질연구
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    • 제13권4호
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    • pp.165-180
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    • 1995
  • The purpose of this study was to investigate the influences of family life cycle stages and perceived time pressure on strategies for coping with time constraints in housewife-teachers. The subjects of this study were 570 married women teachers who live with their husebands and children in junior and senior high schools in Taegu, A questionaire was used as survey method. Factor analysis and MANOVA were employed for data analysis and Scheffe test forpost-hoc analysis. The main findings were : First the effect of family life cycle stages on the use of personal time reducing strategies was different according to perceived time pressure. Second the effect of perceived time pressure on the use of personal time reducing strategies differed according to family life cycle stages. Third the use of strategies for coping with time contratins was found to be significantly different according to family life cycle stages, Forth there were significant differences in the use of strategies for coping with time constrainsts according to perceived time pressure.

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초고층건축물에 사용되는 분기배관의 사용압력에 관한 연구 (A Study on the Working Pressure of TBP used in Tall Building)

  • 이성호;김희송
    • 설비공학논문집
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    • 제20권5호
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    • pp.351-356
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    • 2008
  • In this study, we had the stress analyses of TBP used in Tall Building and determined the working pressure of TBP. We knew the four fact. First, the place acted maximum stress is axial direction of branched part. Second, working pressure is more than 2.0 MPa. Third, stress in branched part is less than yielding strength at hydrostatic test pressure. Fourth, the ratio(stress/yielding stress at hydrostatic test pressure) is $0.4{\sim}0.6$(KS D 3562 Sch 40), $0.3{\sim}0.4$(KS D 3576 20S).

부산지역 일부 성인들의 나트륨, 칼륨의 섭취 및 소변중 배설실태에 관한 연구 (A Study on the Sodium and Potassium Intakes and Urinary Excretion of Adults in Busan)

  • 임화재
    • 대한지역사회영양학회지
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    • 제17권6호
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    • pp.737-751
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    • 2012
  • The purpose of this study was to assess sodium and potassium intakes and urinary excretion of adults in Busan and to evaluate the relationship of urinary sodium/potassium excretion (UNa/UK) to the status of anthropometric, blood pressure, urine analysis, and nutrient intake of subjects. Nutrient intake by 24-h recall, 24-h UNa/UK were measured with 87 adults aged 20-59 yrs (42 men and 45 women). The mean intakes of sodium and potassium were 3915.4 mg and 3093.9 mg, respectively. The mean 24-h UNa/UK was 3457.0/1680.4 mg. UNa showed significant positive correlations with sodium intake (p < 0.001, p < 0.001), sodium/potassium ratio (p < 0.001, p < 0.01), UK (p < 0.001, p < 0.001), and UNa/UK ratio (p < 0.05, p < 0.01) in men and women and with age, BMI, systolic blood pressure (SBP) and diastolic blood pressure in women (p < 0.05, p < 0.05, p < 0.05, p < 0.05). The UK showed significant positive correlations sodium intake (p < 0.001, p < 0.001), UNa (p < 0.001, p < 0.001) in men and women and with sodium density in men (p < 0.001) and with age, intakes of protein and potassium in women (p < 0.01, p < 0.05, p < 0.05). Mean SBP was lowest in the second quartile and highest in the fourth quartile of UNa. Mean UNa in the second, third, and fourth quartiles were 2821.1 mg, 3621.3 mg, and 5456.4 mg, respectively. Mean SBP in the second, third, and fourth quartiles were 115.8 mmHg, 120.7 mmHg, and 125.9 mmHg, respectively. Based on the results, UNa was related to sodium intake, UK, and SBP. We conclude that nutritional education for the reduction of high sodium intake is needed in the general population to prevent and control adverse blood pressure levels.

입원 환자의 욕창예방과 중재를 위한 알고리즘 개발 (Development of an Algorithm for the Prevention and Management of Pressure Ulcers)

  • 김진미;박정숙
    • 성인간호학회지
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    • 제22권4호
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    • pp.353-364
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    • 2010
  • Purpose: The purpose of this study was to develop an algorithm for preventing and managing of pressure ulcer and to verify the its appropriateness. Methods: The first step was development of a pre-algorithm through a literature review and expert opinion. The second step was to establish content validity by submitting the algorithm questionnaires about the content to 12 experts. The third step was the revision of the algorithm. The fourth and last step was to establish the clinical validity of the algorithm with 25 experienced nurses. Results: For the ease of the practitioner the algorithm for prevention and the management of pressure ulcers was confined to one page depicting the main algorithm pathway and seven stepwise guidelines. The guidelines included skin care of pressure ulcer prevention, mechanical loading care, support surface care, reposition care of pressure ulcer, and Stages II, III and IV explanations along with debridement/wound irrigation and infection control. Most of all algorithm courses chosen more than 80% of agreement by expert index of content validity. The usefulness, appropriateness, and convenience of the algorithm were demonstrated through clinical validity with intensive care unit and ward nurses. Conclusion: The algorithm will improve the quality of pressure ulcer nursing care as it provides a model for decision making for clinical nurses as well as providing consistent and integrated nursing care for patients with pressure ulcer throughout an institution.

비예혼합 대향류 화염에서 연소 분위기 압력 영향 연구 (Effects of Combustion Atmosphere Pressure on Non-premixed Counterflow Flame)

  • 이기만
    • Journal of Advanced Marine Engineering and Technology
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    • 제30권8호
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    • pp.853-862
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    • 2006
  • The present study is numerically investigated the flame structure of non-premixed counterflow jet flames using the laminar flamelet model Detailed flame structures with the fuel composition of 40% CO, 30% $H_2$. 30% $N_2$ and an oxidizer composition of 79% $N_2$ and 21% $O_2$ in a non-premixed counterflow flame are studied numerically. This study is aimed to investigate the effects of axial velocity gradient and combustion atmosphere pressure on flame structure. The results show that the role of axial velocity gradient on combustion processes is globally opposite to that of combustion atmosphere pressure. That is, chemical nonequilibrium effects become dominant with increasing axial velocity gradient, but are suppressed with increasing ambient pressure. Also, the flame strength is globally weakened by the increase of axial velocity gradient but is augmented by the increase of ambient pressure. However, flame extinction is described better on the basis of only chemical reaction and in this study axial velocity gradient and ambient pressure play a similar role conceptually such that the increase of axial velocity gradient and ambient pressure cause flame not to be extinguished and extend the extinction limit, respectively. Consequently it is suggested that a combustion process like flame extinction is mainly influenced by the competition between the radical formation reaction and the third-body recombination reaction.

Electrodermal Activity at Palms according to Pressure Stimuli applied to the Scapula

  • Kim, Jae-Hyung;Park, Gun-Cheol;Baik, Sung-Wan;Jeon, Gye-Rok
    • 한국멀티미디어학회논문지
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    • 제19권7호
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    • pp.1137-1145
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    • 2016
  • The system for measuring the electrodermal activity (EDA) signal occurring at the sweet glands in the human body was implemented in this study. The EDA measurement system (EDAMS) consisted of an algometer and the bio-potential measurement system (BPMS). Three experiments were performed using EDAMS. First, the linearity of the output voltage corresponding to the pressure being applied to an algometer was evaluated. The linearity of output voltage according to the pressure was 0.956. Second, the amplitude and the latency of the EDA signal at the left palm was obtained while applying the pressure stimuli to the left and right scapula. The latency of EDA signal was shorter whereas the amplitude of EDA signal was higher when the pressure applied was applied to the left scapula. Third, the amplitude and latency of the EDA was measured at left and right palm while increasing the pressure stimuli to the left scapula. The latency of EDA signal at left and right palm was decreased according to the intensity of pressure stimulus applied to the left scapula. However, the latency of the EDA signals did not show the linearity with respect to the pressure stimuli.

마이크로 프로세서에 의한 환자감시장치의 개발 (Development of the Patient Monitor Using Microprocessor)

  • 김남현;유선국
    • 대한의용생체공학회:의공학회지
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    • 제10권3호
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    • pp.309-316
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    • 1989
  • In this paper, the patient monitor consisting of amplifier, scan converter, A/D converter, CRT amplifier, and micro-controller part was developed. This patient monitor measures the patient's 4 states in the hospital such as electro-cardiography, respiration, blood pressure, and temperature. The control and processing methods based on micro-processor employ the flexibility, extensibility and economy over other conventional system. The followings are incorporated in this system. First, record the heart rate trends for 1 and 4 hours respectively. Second, measures the respiration by impedance pneumography. Third, measures the blood pressure with auto-zero balance. Fourth, linesrize the temperatures by bridge method.

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Wind pressure and buckling of grouped steel tanks

  • Portela, Genock;Godoy, Luis A.
    • Wind and Structures
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    • 제10권1호
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    • pp.23-44
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    • 2007
  • Wind tunnel experiments on small scale groups of tanks are reported in the paper, with the aim of evaluating the pressure patterns due to group effects. A real tank configuration is studied in detail because one tank buckled during a hurricane category 3. Three configurations are studied in a wind tunnel, two with several tanks and different wind directions, and a third one with just one blocking tank. The pressures were measured in the cylindrical part and in the roof of the tank, in order to obtain pressure coefficients. Next, computational buckling analyses were carried out for the three configurations to evaluate the buckling pressure of the target structure. Finally, imperfection-sensitivity was investigated for one of the configurations, and moderate sensitivity was found, with reductions in the maximum load of the order of 25%. The results help to explain the buckling of the tank for the levels of wind experienced during the hurricane.

Modeling of non-isothermal CO2 particle leaked from pressurized source: I. Behavior of single bubble

  • Chang, Daejun;Han, Sang Heon;Yang, Kyung-Won
    • Ocean Systems Engineering
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    • 제2권1호
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    • pp.17-31
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    • 2012
  • This study investigated the behavior of a non-isothermal $CO_2$ bubble formed through a leak process from a high-pressure source in a deep sea. Isenthalpic interpretation was employed to predict the state of the bubble just after the leak. Three modes of mass loss from the rising bubble were demonstrated: dissolution induced by mass transfer, condensation by heat transfer and phase separation by pressure decrease. A graphical interpretation of the last mode was provided in the pressure-enthalpy diagram. A threshold pressure (17.12 bar) was identified below which the last mode was no longer present. The second mode was as effective as the first for a bubble formed in deep water, leading to faster mass loss. To the contrary, only the first mode was active for a bubble formed in a shallow region. The third mode was insignificant for all cases.