• Title/Summary/Keyword: mean contact pressure

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Drawing of Twenty Kinds of State and Process on Psychrometric Chart (습공기선도 상에 20 종류의 상태 및 과정 값의 작도)

  • Kim, Deok-Jin
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.1201-1206
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    • 2008
  • Psychrometric chart displays graphically the thermophysical properties of moist air, so it is very conveniently used in air-conditioning and refrigeration. On general psychrometric chart, there are dry bulb temperature, web bulb temperature, absolute humidity ratio, relative humidity, specific enthalpy, specific volume, sensible heat factor, and enthalpy-humidity difference ratio. However, various state and process values besides aboves can be plotted on psychrometric chart. In this study, we developed the software drawing twenty kinds of lines, that is vapor pressure, mole fraction ratio of vapor, dew point temperature, degree of saturation, density, specific entropy, specific exergy, contact or bypass factor, uncomfort index, discomposition index, predicted mean vote index, predicted percent dissatisfied, and so on. We wish to this software is a help to design, analysis and education.

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Effect of Abdominal Compression Belt on Static Balance During One Leg Standing in Low Back Pain Patients (한 발 서기 시 복부 압박 벨트가 요통 환자의 정적 균형에 미치는 영향)

  • Ju, Hwa-Phyeoung;Choi, Sol-A;Jeong, Da-Hye;Han, Na-Rin;Woo, Young-Keun
    • PNF and Movement
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    • v.15 no.3
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    • pp.353-360
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    • 2017
  • Purpose: This study aimed to measure static balance of low back pain patients while one-leg standing in abdominal compression belts. Methods: The study included 40 adult males and females at J university, divided into a low back pain patient group and a normal group through the Oswestry disability questionnaire (ODQ). The subjects were instructed to hold a one-leg standing posture for 15 seconds on a balance measurement plate while wearing an abdominal compression belt. Shifting distance (0.1 cm), mean velocity (cm/s), pressure, and contact area were analyzed using BioRescue (BioRescue, RMINGEIEIRIE, Rodez, France). The average value was used to measure the result 3 times for each condition. Results: Both normal and low back pain groups significantly decreased in the speed of sway while wearing the abdominal compression belt. Furthermore, the pressure of the center of motion significantly decreased in the low back pain groups while wearing abdominal compression belt. However, there were no significant differences in the speed of sway or the pressure of center of motion between groups after wearing the abdominal pressure belt. Conclusion: These results suggest that abdominal compression belts are one option for improving balance temporarily. However, balance after wearing abdominal compression vests depends on onset of back pain, age, and symptoms of pain in the groups with low back pain. Further research is needed to investigate muscle activity, dynamic balance, and the effect of the period of wearing abdominal compression belts in the variety of low back pain patients.

Safety evaluation of agricultural reservoir embankment according to backside extension (후면 덧쌓기에 따른 농업용 저수지 제체의 안정성 평가)

  • Lee, Dal-Won;Noh, Jae-Jin
    • Korean Journal of Agricultural Science
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    • v.39 no.1
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    • pp.97-110
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    • 2012
  • This study was carried out for safety evaluation, the practical application and improvement of design method of the agricultural reservoir embankment according to backside extension. Seepage analysis, slope stability analysis and finite element analysis were performed for steady state and transient conditions. Also, the pore water pressure, seepage quantity, safety factor and stress-strain behavior according to high water level and rapid drawdown were compared and analyzed. The pore water pressure at contact region between backside extension and old embankment was kept high after rapid drawdown. Therefore, backside extension is recommended that design method is required to be improved and reinforced more than the others raising embankment. The hydraulic gradients before and after backside extension showed high value at the base of the core, but they showed stable state at the upstream slope and downstream slope. The seepage quantity per 1 day and the leakage per 100 m for the steady state and transient conditions appeared to be safe against the piping. The safety factor of slope stability showed high at the steady state, and transient conditions did not show differences depending on the rapid drawdown. The safety factor was appeared high at the upstream slope before backside extension and downstream slope after extension. The excess pore water pressure for steady state and transient conditions showed negative(-) at the upstream slope, it was small at the downstream slope. The mean effective stress (p') showed high at the base of the core and to be wild distribution after the extension. The displacement after extension showed 0.02-0.06 m in the upstream slope, the maximum shear strain after extension was smaller than that before extension.

Geothermometrical Studies of Fluorite Deposits with special reference to the Studies of Fluorites from the Wolaksan area and Cheonil Mine, Chungcheongbuk-Do (형석광상(螢石鑛床)의 지질온도측정(地質溫度測定) 연구(硏究) 특(特)히 충북(忠北) 월악산지대(月岳山地帶) 및 천일광산(天一鑛山) 형석(螢石)의 연구(硏究)를 중심(中心)으로)

  • Yun, Suckew
    • Economic and Environmental Geology
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    • v.6 no.4
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    • pp.195-200
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    • 1973
  • Temperature environments of the formation of fluorite deposits in the Wolaksan area and the Cheonil Mine, Chungcheongbuk-Do are presented and interpreted in brief. These deposits occur more or less near the contact zone between the Paleozoic limestone formations and the Cretaceous biotite granites as a number of hydrothermal veins or replacement deposits. The homogenization temperatures of fluorite crystals from the Wolaksan area fall within the narrow range of $149{\sim}167^{\circ}C$, of which lower limit is quite high, while those of the Cheonil Mine show wide range of $126{\sim}177^{\circ}C$, which indicates much lower mean temperature of formation. If the possible correction for pressure, which may not exceed $+30^{\circ}C$ as the depth of the deposits was 1.5km, were applied, the possible highest value of the true formation temperatures of fluorites in both area might be reached to around $200^{\circ}C$ that means these deposits were formed as a series of early products of the epithermal stage of hydrothermal processes.

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Interfacial shear stresses and friction factors in nearly-horizontal countercurrent stratified two-phase flow (근사수평 반류성층 2상유동에서의 계면전단응력 및 마찰계수)

  • 이상천;이원석
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.1
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    • pp.116-122
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    • 1988
  • Interfacial shear stresses have been determined for countercurrent stratified flow of air and water in a nearly-horizontal rectangular channel, based upon measurements of pressure drop, gas velocity profiles and mean film thickness. A dimensionless correlation for the interfacial friction factor has been developed as a function of the gas and liquid Reynolds numbers. Equivalent surface roughnesses for the interfacial friction factor have been calculated using the Nikuradse correlation and have been compared with the intensity of the wave height fluctuation on the interface. The results show that the interfacial shear stress is mainly affected by turbulent mixing near the interface due to the wave motion rather than by the roughened surface.

The effect of the Modified Voiced Lip Trill (MVoLT) training on vocal changes of musical theater students (응용 입술 트릴 훈련이 뮤지컬 전공 학생의 음성 변화에 미치는 효과)

  • Lee, Seung Jin;Choi, Hong-Shik;Lim, Jae-Yol;Lee, Kwang Yong
    • Phonetics and Speech Sciences
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    • v.10 no.4
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    • pp.135-146
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    • 2018
  • The Modified Voiced Lip Trill (MVoLT) training is a variant of voiced lip-till training characterized by increased loudness, lowered laryngeal position, and lip contact facilitated with fingers. The purpose of the current study was to assess the effect of the MVoLT training program on vocal changes of musical singing theater students. A total of 32 musical theater students (17 males and 15 females, age ranging from 18 to 29) participated in the study. For about three months, each participant was tutored using a systematic program focussing on the MVoLT training, accompanied by certain facilitating strategies. Pre- & post-training multi-dimensional vocal characteristics were assesed and compared. Results showed that cepstral peak prominence during vowel phonation increased after training, while its standard deviation and Cepstral Spectral Index of Dysphonia decreased. When an aerodynamic assessment was performed, maximum phonation time, subglottal pressure, mean airflow rate increased, while electroglottographic measures did not change. In addition, decreased psychometric measures, higher maximum pitch, and increased vocal range were noted after training. In conclusion, the MVoLT was proven to have a potential as an effective and safe training method for musical theater singing.

The Clinical Nurses' Knowledge, Attitudes, and Performance on Incontinence Associated Dermatitis (임상간호사의 실금 관련피부염에 대한 지식, 태도 및 수행 정도)

  • Kim, Jung Yoon;Dong, Cha Bun;Lee, Yun Jin;Ju, Myoung Jean
    • Journal of Korean Clinical Nursing Research
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    • v.30 no.2
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    • pp.114-124
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    • 2024
  • Purpose: Incontinence-associated dermatitis (IAD) is widespread and a common problem in healthcare settings, It is defined as irritation of the perineal skin due to contact with urine, feces, or both. It is one of the major risk factors for the development of pressure injuries are regarded as a quality indicator of nursing care. It is important to understand the knowledge and attitudes of nurses who are primarily responsible for providing appropriate nursing care that includes differentiation of IAD from other skin breakdowns, and appropriate management. Therefore, the purpose of this study was to determine the knowledge, attitudes, and performance of IAD among clinical nurses in Korea. Methods: Data about IAD knowledge, attitudes, and performance were collected from August to November 2022. 656 nurses from six hospitals participated in the study. Results: The mean scores of nurses' knowledge, attitudes, and performance were 17.98±2.91, 76.34±7.85, and 91.53±16.18, respectively. Nurses' knowledge showed a positive correlation in both attitudes (r=0.27, p<.001) and performance (r=0.09, p=.02), and attitudes and performance (r=0.34, p<.001) also showed a positive correlation. Conclusion: To improve the knowledge and performance of nurses, an educational program consisting only of incontinence-related dermatitis is needed, and case-based education and clinical skills education are needed to enhance the ability to differentiate from pressure injury.

Inter-device agreement between spectral domain optical coherence tomography, ultrasound biomicroscopy, and gonioscopy in evaluating the iridocorneal angle in normotensive dogs

  • Su An Kim;Jaeho Shim;Seonmi Kang;Kangmoon Seo
    • Journal of Veterinary Science
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    • v.24 no.4
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    • pp.34.1-34.12
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    • 2023
  • Background: There has not been a thoroughly reported study of the comparison between spectral domain-optical coherence tomography (SD-OCT) with both ultrasound biomicroscopy (UBM) and gonioscopy on the evaluation of the iridocorneal angle (ICA) in dogs. Objectives: To investigate the diagnostic value of SD-OCT for the early detection of narrowing ICA by comparing and assessing inter-device agreement in anterior chamber angle (ACA) measurements obtained by SD-OCT and UBM, and ICA evaluations by gonioscopy. Methods: A total of 28 eyes from 28 client-owned dogs with normal intraocular pressure were included for examination. The ACA and angle opening distance (AOD) were measured from the SD-OCT and UBM images, and gonioscopy images were analyzed using the ICA grade and ZibWest angle index. Results: The mean ACA and AOD for SD-OCT were 28.31° ± 5.37° and 658.42 ± 219.90 ㎛, and for UBM, 28.34° ± 5.82° and 859.29 ± 221.80 ㎛, respectively. The mean difference in ACA between the average values of SD-OCT and UBM measurements was 0.03° with a 95% limit of agreement (LoA) span of 16.2°, indicating positive agreement; that in AOD was 200.85 ㎛ with a 95% LoA span of 1,110.95 ㎛, indicating poor agreement. The Pearson correlation coefficient of the ACA of SD-OCT and ZibWest indices of gonioscopy was 0.624, indicating strong agreement; that of UBM and gonioscopy was 0.43, indicating moderate agreement. Conclusions: SD-OCT is well tolerated by canine patients due to its non-contact method and might be an alternative option for early screening of ICA narrowing in clinical settings.

A Study of the Variation Factors of Intraocular Pressure (안압 변동 요인에 관한 연구)

  • Kim, Sang-Moon
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.1
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    • pp.131-135
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    • 2008
  • Purpose: To measure and quantify the factors of intraocular pressure (IOP) variation for normal Korean youth. Methods: The IOP of normal youth 805 persons (male: 367, female: 438) were measured as a function of time and quantity for fixation, reclining posture, hard blinking, drinking water, drinking hard liquor, tobacco and coffee by using non-contact tonometer (AT555, Reichert Co.). In the case of fixation, reclining posture and hard blinking, the intraocular pressure of right and left eye were measured for 6 males and 6 females every 10 minutes during 30 minute. In the case of water, liquor, tobacco and coffee, the measurement for 4 or 5 groups (6 persons/ group) having similar IOP were done for the IOP variation of right eye. Results: The mean IOP was 15.2 mmHg for males and 15.8 mmHg for females (slightly higher than male's), respectively and the 99% of those were in the range of the normal IOP. The measured IOP was increased by fixation, reclining posture and hard blinking with males and females. The gradient of increasing slope was 0.15/0.13/0.07/0.08, 0.09/0.08/0.08/0.08 and 0.19/0.08/0.26/0.31, respectively. The IOP variation was elevated by drinking water (especially in the case of 1000 ml) and lowered in proportion to the amount of drinking by hard liquor. Cigarette smoking was associated with rise in intra ocular pressure, but was not shown a definite relation. And coffee had virtually no effect. Conclusions: Fixation, reclining posture, hard blinking and Tobacco caused a transient increase in IOP, but alcohol elicited a slight reduction in IOP overall.

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The Effect of Barrel Vibration Intensity to the Plating Thickness Distribution

  • Lee, Jun-Ho;Roselle D. Llido
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 1999.10a
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    • pp.15-15
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    • 1999
  • In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the conventional rotating barrel. vibrational barrel (vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components, The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed that the average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value, Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components, However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. $2HD{\;}+{\;}e{\;}{\rightarrow}20H{\;}+{\;}H_2$ Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure thereby resulting to bad plating condition. 1 lot of chip was divided into two equal partion. Each portion was loaded to the same barrel one after the other. Nickel plating and tin-lead plating was performed in the same station. Portion A maintained the normal barrel vibration intensity and portion B vibration intensity was increased two steps higher. All other parameters, current, solution condition were maintained constant. Generally, plating method find procedures were carried out in a best way to maintained the best plating condition. After plating, samples were taken out from each portion. molded and polished. Plating thickness was investigated for both. To check consistency of results. 2nd trial was done now using different lot of another characteristics.

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