• Title/Summary/Keyword: 이완계수

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A study on the reduction of concrete lining re-bar according to the tunnel design factors (터널 설계인자 평가에 따른 콘크리트 라이닝 철근량 절감에 관한 연구)

  • Kang, Si-On;Lim, Young-Duck;Shin, Jeong-Ho;Kim, Sang-Hwan
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.1
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    • pp.197-209
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    • 2018
  • This paper presents a study on the reduction of concrete lining re-bar according to the tunnel design factors. The design of the concrete lining increases the reinforcing re-bar according to the application of excessive load, and the economical efficiency is reduced. In order to improve the economical efficiency of tunnel construction, rational standards are required for the design factors of concrete lining. Therefore, this research analyzed the characteristics and problems of the design factors applied to the design of concrete lining. Also, the economical review of the concrete lining for design factor application was compared with the amount of reinforcing re-bar calculated from the section design using numerical analysis. The results show that the amount of re-bar is varied according to the design factors. That is, the required amount for re-bar in the tunnel concrete lining could be reduced in the design stage. The results of this study may be useful for economic design of concrete lining in the future.

The Sibling Relationship, the Attachment to Parent and Peer by Birth Order and Sibling Gender Composition (출생순위와 형제간 성별 구성에 따른 형제관계의 질과 부모애착 및 또래애착)

  • Lee, Jae Youn;Lee, Wan Jeong
    • Korean Journal of Childcare and Education
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    • v.2 no.2
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    • pp.129-146
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    • 2006
  • The objective of this study was to investigate the sibling relationship, the attachment to parent and peer according to children's gender, birth order, and sibling gender composition. For this purpose, 697 male and female elementary students answered the questionnaire, who were selected because they had only one sibling. The date were analysed by t-test and partial correlation. The major finding of this study showed that children who had same sex of sibling perceived more positive way to their younger sibling then children who had different sex of sibling and that children who had female sibling perceived more positive way to sibling relationship, attachment to parent and their peers than children who had male sibling.

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Characteristics of a Solder-Clad FBG Temperature Sensor (땜납이 용융 부착된 FBG 온도 센서의 특성)

  • Pyoung, Jae-Hyub;Lee, Sang-Bae;Shin, Jong-Dug
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.10
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    • pp.45-50
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    • 1999
  • We report a solder-clad fiber Bragg grating(FBG) temperature sensor in order to obtain better Bragg wavelength sensitivity to temperature than a bare FBG sensor. The solder-clad FBG sensor shows a wavelength sensitivity improvement by a factor of four compared to the case of a bare FBG sensor at temperatures below $110^{\circ}C$. However, it has a sensitivity of 0.01 $nm/^{\circ}C$ at temperatures over $110^{\circ}C$, which is identical to that of a bare FBG sensor. Bragg wavelength of the sensor shows a blue-shift below $110^{\circ}C$ because the sensor is fabricated above melting temperature of solder. The thermal stress at the FBG-solder interface has been relieved by annealing, which results in a stable operation.

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The Effects of Red Ginseng on Blood Pressure and the Quality of Life in Essential Hypertensives (본태성 고혈압 환자의 혈압과 생활상에 미치는 홍삼의 영향)

  • Imamura Yoichi;Kuwashima Keiichi
    • Proceedings of the Ginseng society Conference
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    • 1988.08a
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    • pp.87-91
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    • 1988
  • We studied the effects of red ginseng on blood pressure (BP) and the quality of life (QOL) in 19 hypertensive patients treated with antihypertensive agents. Red ginseng was administered at a dosage of three grams a day for three months. Systolic blood pressure was significantly lowered during the administration period of red ginseng. while diastolic blood pressure and hear1 rate remained unchanged. QOL was significantly improved in $89\%$ of the patients. Among the QOL variables. sleep disorder. thirst. fatigue. mood. sexual life and general well-being were improved. Furthermore. an improved coefficient of variation of R-R intervals $(CV_{R-R})$ was observed during the period. A month after the cessation of red ginseng systolic blood pressure returned to the level before the administration and QOL variables detariorated to previous pre-treatment states. These results suggest that red ginsing may lower systolic blood pressure and may improve QOL in patients treated with antihypertensive agents.

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Moment Resisting Behaviors of Railway Electric Pole Foundation According to Form Work Methods (거푸집 설치 방법에 따른 철도 전철주기초의 모멘트 저항 거동)

  • Lee, Su-Hyung;Lee, Seung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.1
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    • pp.411-417
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    • 2013
  • The moment responses of electric pole foundations for a railroad were investigated using real-scale load tests. Large overturning moments were applied to two square rigid piles with a 1.1 m width and a 2.2 m embedded depth. Two different installation methods-with and without a form-were applied to evaluate the influence of the form work on the moment capacities of the foundations. The reduction of ground strength caused by the excavation without a form is more pronounce than the decrease of frictional strength due to the smooth concrete surface with a form. From the test results, it is found that the current design method which applies a proportional coefficient to consider the effect of a form work is not appropriate. When the normal and frictional stressed is considered separately, the effect of a form work can be estimated reasonably by reducing the friction angle between soil and foundation by 20%.

Analysis of Fine Particle Transfer and Shear Strength Increase Using PFC in Permeation Grouting (PFC를 이용한 침투그라우팅시 미세입자의 이동 및 전단강도증가 해석)

  • Lee, Wan-Ho;Lim, Heui-Dae
    • Journal of the Korean Geotechnical Society
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    • v.23 no.11
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    • pp.49-58
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    • 2007
  • Numerical experiments using a distinct element code (PFC3D) were carried out for the analysis of grout-material transfer in soil layers and also for the analysis of increase in mechanical strength after permeation grouting. For rapid analysis, up-scaling analysis in length scale was adopted, and the following observations were made from the numerical experiments. Firstly, the relative size of grout material with respect to the in situ soil particles controlled the transfer distance of the grout particles. When the size of grout particle was 0.2 to 0.25 times of the in situ soil particles, clogging of pore spaces among the in situ soil particles occurred, resulting in restricted propagation of grout particles. It was also found that there was a threshold value in the size of grout particle. Below the threshold value, the transfer distance of the grout particle did not increase with the decrease of particle size of the grout material. Secondly, the increase in cohesion and internal friction angle was observed in the numerical specimen with grouting treatment, but not with the untreated specimen.

Comparison of Measuring Methods for Somatic Cell Count in Goat Milk (측정방법에 따른 국내산 산양유의 체세포수 비교)

  • Lee, Seung-Gyu;Kim, Min-Kyung;Lee, Yeon-Jeong;Jeong, Seok-Geun;Oh, Mi-Hwa;Kim, Dong-Hun;Park, Kwang-Wook;Lee, Wan-Kyu;Ham, Jun-Sang
    • Food Science of Animal Resources
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    • v.30 no.1
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    • pp.120-123
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    • 2010
  • The standard method for somatic cell counts in goat milk is the direct microscopic method after a pyronin Y-methyl stain. It has been reported, however, that are found to differ by measuring methods, but. A total of forty eight goat milk samples from eight farms were compared by pyronin Y-methyl stain, ADAM-SCC in National Institute of Animal Science, and Somacount 500 in Chungbuk Veterinary Service. The average SCC of the samples was $7.3{\times}10^5$ cells/mL by pyronin Y-methyl stain, $4.9{\times}10^5$ cells/mL by ADAM-SCC, and $11.6{\times}10^5$ cells/mL by Somacount 500. The correlations between the methods were not significant. SCC measuring equipment should be developed for reducing the SCC in goat milk, and pyronin Y-methyl green stain for estimating SCC in goat milk should be included in NVRQS Notice for livestock products processing and composition standards.

A Proposal of a Model for the Generation of Weathered Residual Soils (풍화잔류토의 생성모델의 제안)

  • Min Tuk-Ki;Lee Wan-Jin
    • Journal of the Korean Geotechnical Society
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    • v.20 no.9
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    • pp.47-56
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    • 2004
  • A new fragmentation model, called the GRS (the generation model of weathered residual soils) model, was proposed in this study, This model could identify the formation of a residual soil. This model is based on the phenomena that as the soil was weathered more highly, soil particles were smaller and pores were more expanded simultaneously. The possibility of fragmentation, $P_F,$ which was based on the fractal theory, was introduced in this model. There were some fundamental notions in the GRS model that soil particles were generated as the rock is fragmented, and the fragmentation of the rock was performed step by step. The $P_F,$ of the rock was not constant at each fragmentation steps. As a result of application on the GRS model, there were more residue where $P_{Fi}s$ were small at any particle size. There was a S-shape of PSD curve at the concave shape of $P_{Fi},$ and the PSD curve goes to a gaped graded curve at the convex shape of $P_{Fi}.$ The shape of PSD curve was concave in the case of small $P_{Fi}s.$ The value of $P_{Fi}$ increased with the coefficient of uniformity $(C_u)$ and the fragmentation fractal dimension $(D_r),$ but had no relation with the coefficient of gradation $(C_C)$.

The Clinical Comparision of Amrinone and Dopamine after Open Heart Surgery (개심술후 암리논과 도파민의 효과에 대한 임상 비교)

  • 이성호;이현재
    • Journal of Chest Surgery
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    • v.29 no.2
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    • pp.191-198
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    • 1996
  • Amrinone is a non-glycosidic, non-adrenergic positive inotropic agent with peripheral and coronary vasodilator effect. It inhibits phosphodiesterase F-III, the cardiac cyclic-AMP specific phosphodiesterase, selectively and potently. In this study, the effects of IV administered amrinone and dopamine were compared in 40 patients who had open heart surgery. Amrinone was administered as a bolus of 1 5~2mglkg for several minutes, followed by continuous infusion at 5~1 Oug/kg/min. The hemodynamic measurements including heart rate, systolic and diastolic pressure, cardiac index, pulmonary wedge pressure, and systemic vascular resistance were recorded immediately for 12~24 hours awl 7th day following operation. In amrinone group, cardiac index increased from 3.73$\pm$1.39 L/min/m2 to 5.44$\pm$2.65 L/min/m2 at the time of posterative 48 hours (n=20, p< 0.05). The decrease in systemic vascular resistance from 1237.5 $\pm$ 637.7 dyne/sec/cm2 to 1000.8 $\pm$ 608.5 dyne/sec/cm2(p<0.05). In Dopamine group, the heart rate increased from 92.1 $\pm$ 13.0/min to 101.0 $\pm$ 13.1/min and the cardiac index decreased from 3.40 $\pm$ 0.50 L/min/m2 to 2.53 $\pm$ 1.15 L/min/m2 at the time of postoperative 12 hours(p<0.05). Systemic vascular resistance increased from 1058.5 $\pm$ 234.6 dyne/sec/cm2 to 1979.7 $\pm$ 759.2 dynelsec/cm2 The comparison of the hemodynamic effects of amrinone and dopamine, both drugs improved cardiac performance. But the administration of amrinone results in a higher cardiac index, diastolic blood pressure and lower systemic vascular resistance than those achieved with dopamine (p<0.05). The uniqueness of the action of amrinone on the heart and its sustained hemodynamic effect suggest it has clinical promise, pos operative care of cardiac surgery

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Cardiovascular Effects of Free Movement of Abdominal Muscle in Prone Positioning during General Anesthesia (전신마취동안에 복와위시 자유로운 복근 움직임이 심혈관계에 미치는 영향)

  • Kim, Ji-Yoon;Lee, Dong-Won;Seo, Il-Sook;Kim, Sae-Yeon
    • Journal of Yeungnam Medical Science
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    • v.24 no.2
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    • pp.206-215
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    • 2007
  • Background : The prone position is often used for operations involving the spine and provides excellent surgical access. The complications associated with the prone position include ocular and auricular injuries, and musculoskeletal injuries. In particular, the prone position during general anesthesia causes hemodynamic changes. To evaluate the cardiovascular effects of the prone position in surgical patients during general anesthesia, we investigated the effects on hemodynamic change of the prone position with the Jackson spinal surgery table. Materials and Methods : Thirty patients undergoing spine surgery in the prone position were randomly selected. After induction of general anesthesia, intra-arterial and central venous pressures (CVP) were monitored and cardiac output was measured by $NICO^{(R)}$. We measured stroke volume, cardiac index, cardiac output, mean arterial pressure, heart rate, CVP and systemic vascular resistance (SVR) before changing the position. The same measurements were performed after changing to the prone position with the patient on the Jackson spinal surgery table. Results : In the prone position, there was a significant reduction in stroke volume, cardiac index and cardiac output. The heart rate, mean arterial pressure and CVP were also decreased in the prone position but not significantly. However, the SVR was increased significantly. Conclusion : The degree of a reduced cardiac index was less on the Jackson spinal surgery table than other conditions of the prone position. The reduced epidural pressure caused by free abdominal movement may decrease intraoperative blood loss. Therefore, the Jackson spinal surgery table provides a convenient and stable method for maintaining patients in the prone position during spinal surgery.

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