• Title/Summary/Keyword: Volume change

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A Study on the Volume Change in Unsaturated Clayey Soil (불포화 정성토의 체적변화에 대한 연구)

  • Chang, Pyoung-Wuck;Gil, Sang-Choon
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.40 no.5
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    • pp.37-42
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    • 1998
  • This study was performed to evaluate the characteristics of volume change is unsaturated clayed soil. The medium-plastic clay was selected and compacted by 50% of Proctor standard compaction energy at 6% higher moisture content than its OMC. A series of isotropic compression tests and triaxial shear tests were performed. The results of the study are summarized as follows. At each matric suction, when the matric suction was increased, the yield stress was increased and slope of volume change was decreased. The more net mean stress was, the less the quantity of volume change was. In shear test, the volumetric strain was much rapidly changed in large matric than in low matric suctions. But the effect of matric suction to volume change disappeared under high net mean stress. At lower deviator stress the more matric suction was, the higher volume change was. But As the matric suction was increasing, the behavior of the unsaturated clayey soil was similar to that of saturated clayey soil. Volume change in the unsaturated clayey soil can be represented as a unique plane in three-dimensional space, which is the axes of net mean stress, matric suction and void ratio.

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Gastrointestinal Tissue Blood Volume Affected by Venous Pressure Change (실혈 후 및 혈압상승 후의 소화기 조직 혈액량 및 산소 섭취량 -제 1 편 정맥혈압과 소화기 조직 혈액량-)

  • Yoon, Byong-Hak;Nam, Kee-Yong
    • The Korean Journal of Physiology
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    • v.2 no.1
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    • pp.9-15
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    • 1968
  • Changes in gastrointestinal tissue blood volume induced by variations of venous pressure between 6 and 40 mmHg were studied in 32 rabbits. Venous pressure lowering was produced by withdrawal of appropriate volume of blood and venous pressure elevation was obtained by partial occlusion of intra-thoracic vena cava inferior. Estimation of regional tissue blood volume was performed by means of regional distribution of injected $Cr^{51}-labeled$ red blood cells. The following results were obtained. 1. At the normal control venous pressure value of 18 mmHg, spleen showed the highest value of tissue blood volume expressed on weight basis, namely, $111{\mu}l/gm$, Liver tissue blood volume was $95\;{\mu}l/gm$, small intestine 24 and stomach $21\;{\mu}l/gm$, respectively. 2. Linear relationships were observed between venous pressure change and gastrointestinal tissue blood volume. The coefficients of correlation were: in spleen r=0.723; in liver r=0.791; in stomach r=0.704, respectively. In small intestine the relationship was less clear and r=0.358. Tissue blood volume of extrabdominal tissue, such as M. gastrocnemius was not influenced by venous pressure change. 3. The highest change in tissue blood volume expressed on weight basis was observed in spleen. The liver tissue showed the next highest change. Change in total tissue blood volume, however, was greatest in liver and next greatest in small intestine. This was interpreted by the fact that total weight of these two organs was much greater than that of spleen. 4. The mechanism that the change in tissue blood volume lies in the venous system which has a great compliance was discussed.

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A Study on the Change of Volume and Temperature in Aqueous Binary Solvent with Ethanol (물과 에탄을 이성분 혼합용매 계에서 부피 및 온도 변화에 관한 연구)

  • 김용권;임귀택
    • Journal of Korean Elementary Science Education
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    • v.20 no.1
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    • pp.139-147
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    • 2001
  • This paper is to study on the change of volume and temperature of the solution which mixed water with ethanol. And its main purpose is to examine closely how the volume changes, and to find the method to maximize the change of the volume. The summaries for results of the study are; First, we were known that water and ethanol are homogeneously mixed. But two solvents does not mix homogeneously by different specific gravity at early stages. Second, we could see that the volume changed large at homogeneous mixed water with ethanol by stirrer, the change of volume is the largest value when water mixed with ethanol in the ratio of one to one. Third, when water mixed with ethanol in the ratio of one to one, the change of temperature is very large by activated hydrogen bond. We conclude that it is the best result when ratio of water and ethanol is one to one and the solution is well mixed.

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Volume Change of the Dredged Materials in the Coastal Lagoon with Coagulants and Flocculants Injection (응집제 및 응결제 주입에 의한 석호 준설물질의 체적변화)

  • 조홍연;윤길림
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.14 no.3
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    • pp.192-200
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    • 2002
  • There is a volume change between the sediments and the dredged materials because the dredged materials is fully disturbed by the dredger and settled in the basin from the stabilized condition. The volume of the dredged materials is also affected by the coagulants and flocculants (hereafter C & F) which was used to speed up the settling of the suspended solids. In this study, the volume change of the dredged materials is analysed in detail due to the injection amount of the C & F. The dredged materials were sampled in the lagoon located in the East coastal zone, and the volume change of the samples is quantitatively analysed by the laboratory test due to the change of the clay content and the amount of the C & F. The optimal amounts of the C & F is determined by showing the minimal volume change due to C & F injection. From the experimental results, the volume of the dredged materials is increased 1.68 times on an average and the volume change rate is slightly increased, i.e., negligible, as the clay content increase in the case of the C & F injection.

College Students' Misconception about the Volume Change of Solution during Acid/Base Titration: Partial Molar Volume of Salt (산·염기 적정에서 용액의 부피 변화에 대한 대학생들의 오개념 연구)

  • Jang, Nak Han
    • Journal of Science Education
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    • v.33 no.2
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    • pp.317-320
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    • 2009
  • I investigated Korean college students' conception about the volume change of solution when they detected the equivalence point during acid/base titration experiment using method of volume measurement. According to this study, most college students had a misconception that the volume increment was due to the formation of water by neutralization during acid/base titration. However, this is not enough to explain the volume change, neglecting contribution of a salt in solution. I calculated the partial molar volume of NaCl formed to explain the volume increment of solution during HCl/NaOH neutralization. Comparing the result of experiment with the calculation of partial molar volume, I elucidated that the main effect of volume increment was due to the partial molar volume of NaCl formed during HCl/NaOH neutralization. Here I propose to introduce college students to the concept of partial molar volume of the salt formed to reduce misconception about the volume change of solution during acid/base neutralization.

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Failure Analysis of RC Cylindrical Structures using Volume-Control Method (체적제어법에 의한 철근 콘크리트 원통형 구조물의 파괴 해석)

  • 송하원;방정용;변근주
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1999.04a
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    • pp.195-202
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    • 1999
  • In this Paper, a so-called volume-control method for nonlinear failure analysis of reinforced concrete cylindrical structures is proposed. The pressure node which defines uniform change of pressure on finite element is added into layered shell element utilizing in-plane constitutive models of reinforced concrete and layered formulation. With the pressure node formulation, one can control the change in volume enclosed by the cylindrical structures and determine the required change in pressure. An algorith of volume-control method is employed and failure analyses for RC cylindrical structures are carried out using proposed method.

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Quantitative Analysis of the Orbital Volume Change in Isolated Zygoma Fracture (관골 단독 골절에서 안구 용적 변화의 정량적 분석)

  • Jung, Han-Ju;Kang, Seok-Joo;Kim, Jin-Woo;Kim, Young-Hwan;Sun, Hook
    • Archives of Plastic Surgery
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    • v.38 no.6
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    • pp.783-790
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    • 2011
  • Purpose: The zygoma (Zygomaticomaxillary) complexes make up a large portion of the orbital floor and lateral orbital walls. Zygoma fracture frequently causes the posteromedial displacement of bone fragments, and the collapse or overlapping of internal orbital walls. This process consequently can lead to the orbital volume change. The reduction of zygoma in an anterolateral direction may influence on the potential bone defect area of the internal orbital walls. Thus we performed the quantitative analysis of orbital volume change in zygoma fracture before and after operation. Methods: We conducted a retrospective study of preoperative and postoperative three-dimensional computed tomography scans in 39 patients with zygoma fractures who had not carried out orbital wall reconstruction. Orbital volume measurement was obtained through Aquarius Ver. 4.3.6 program and we compared the orbital volume change of injured orbit with that of the normal contralateral orbit. Results: The average orbital volume of normal orbit was 19.68 $cm^3$. Before the operation, the average orbital volume of injured orbit was 18.42 $cm^3$. The difference of the orbital volume between the injured orbit and the normal orbit was 1.18 $cm^3$ (6.01%) on average. After operation, the average orbital volume of injured orbit was 20.81 $cm^3$. The difference of the orbital volume between the injured orbit and the normal orbit was 1.17 $cm^3$ (5.92%) on average. Conclusion: There are considerable volume changes in zygoma fracture which did not accompany internal orbital wall fracture before and after operation. Our study reflects the change of bony frame, also that of all parts of the orbital wall, in addition to the bony defect area of orbital floor, in an isolated zygoma fracture so that it evaluates orbital volume change more accurately. Thus, the measurement of orbital volume in isolated zygoma fractures helps predict the degree of enophthalmos and decide a surgical plan.

Accuracy Evaluation of Tidal Volume Measured on the Abdomen (복부에서 측정하는 일회 호흡용적의 정확도 평가)

  • Lee, In-Kwang;Kim, Seong-Sik;Jang, Jong-Chan;Kim, Koon-Jin;Kim, Kyung-Ah;Lee, Tae-Soo;Cha, Eun-Jong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.7
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    • pp.1298-1303
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    • 2008
  • Respiration is induced by muscular contraction of the chest and abdomen, resulting in the abdominal volume change. Thus, continuous measurement of the abdominal dimension enables to monitor breathing activity. Conductive rubber cord has been previously introduced and tested to develop wearable application for respiratory measurements. This study implemented respiratory monitoring system with the conductive rubber cord in the patient's pants in purpose of quantitative estimation of tidal volume. Air mixed with $0{\sim}5%$ $CO_2$ was inhaled and the respiratory air flow rate, abdominal dimension change, and end tidal $CO_2$ concentration were simultaneously measured in steady state. $CO_2$ inhalation significantly increased the tidal volume in normal physiological state with the subject unawared. The tidal volume estimated from the abdominal dimension change linearly correlated with the tidal volume measured by a pneumotachometer with a correlation coefficient of 0.88. Customized calibration for each subject resulted in relative errors less than 10%. Therefore, the tidal volume was accurately estimated by measuring the abdominal dimension change.

The Experimental Study on the continuous Anti-bacterial Potency of Coptidis rhizoma extract on Cultivation of Staphylococcus species(S. aureus, S. epidermidis) (황련(黃連) 전탕액(煎湯液)이 Staphylococcus species(S.aureus, S.epidermidis)의 배양일에 따른 항균효과의 지속성에 관한 연구)

  • Seo, Hyeong-Sik
    • Journal of Pharmacopuncture
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    • v.10 no.3
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    • pp.71-76
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    • 2007
  • Objectives This experimental study was performed to investigate the continuous anti-bacterial potency of Coptidis rhizoma extract on cultivation of Staphylococcus species(S. aureus, S. epidermidis) that induce eye disease. Methods Minimal inhibitory concentration(MIC) was measured by dropping to $50{\mu}l$ diluted Coptidis rhizoma extract(100%, 10%, 1%, 0.1%) on S. aureus, S. epidermidis that were cultivated from 2 to 6 days. Anti-bacterial potency was measured by the size of inhibition zone with change of volume($20{\mu}l,\;30{\mu}l,\;40{\mu}l,\;50{\mu}l$). Results 1. Anti-bacterial potency of Coptidis rhizoma extract on S. aureus was appeared in 100%, 10% and was the same as anti-bacterial potency of 2 days and 6 days. Anti-bacterial potency with change of volume(100%) was increased in propotion to increase volume on all samples. Anti-bacterial potency with change of volume(10%) was increased in propotion to increase volume on all samples except $20{\mu}l$. Anti-bacterial potency of Coptidis rhizoma extract on S. aureus was appeared continuous. 2. Anti-bacterial potency of Coptidis rhizoma extract on S. epidermidis was appeared in 100%, 10% and was the same as anti-bacterial potency of 2 days and 6 days. Anti-bacterial potency with change of volume(100%) was increased in propotion to increase volume on all samples. Anti-bacterial potency with change of volume(10%) was appeared in $50{\mu}l$. Anti-bacterial potency of Coptidis rhizoma extract on S. epidermidis was appeared continuous. Conclusions Anti-bacterial potency of Coptidis rhizoma extract on cultivation of S. aureus & S. epidermidis was showed continuous.

The Effects of Additives on the Cooling Characteristic of a Clathrate Compound (포접화합물의 냉각특성에 대한 첨가제의 영향)

  • Kim Jin Heung;Chung Nak Kyu;Kim Suk Hyun;Kim Chang Oh
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.2
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    • pp.125-130
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    • 2005
  • This study was peformed to investigate the phase change temperature, the supercooling, the maintenance time of liquid phase and the change rate of volume of TMA 30 $wt\% clathrate compound with additives. TMA 30 $wt\% clathrate compound with additive was cooled at heat source temperature of $-6^{circ}C$. The additives are ethylene glycol and chloroform. Their concentration are 0.1$wt\% respectively. The experimental results showed that the phase change temperature was not affected by additives and this was average $5.3^{circ}C$. Also the supercooling and the maintenance time of liquid phase were decreased by additives. Especially, the average value of supercooling showed by $8.8^{circ}C$ and the maintenance time of liquid phase was by 19 minutes in the case of chloroform 0.1$wt\%. Additionally, the average change rate of volume showed by $1.26{\~}1.31\%$ according to additives and the volume was decreased by the phase change from liquid to solid.