• Title/Summary/Keyword: volume-rate

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The Interaction of Vortex and Premixed Flame with Consideration of Volume Expansion Effect (체적팽창효과를 고려한 예혼합화염과 와동의 상호작용에 관한 연구)

  • Jeong Ui-Heon;Gwon Se-Jin
    • 한국전산유체공학회:학술대회논문집
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    • 1998.11a
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    • pp.204-210
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    • 1998
  • A method is developed to include the effect of volume expansion in the description of the flame dynamics using G-equation. Line volume-source is used to represent the effect of the exothermic process of combustion with source strength determined by the density difference between the burned and the unburned region. Volume expansion adjusts the flow field to accommodate the increased volume flow rate crossing the flame front. Test result predicted the measured velocity field qualitatively. The method was applied to study the interaction of vortex and premixed flame. Increased volume expansion did not change the initial growth rate of flame area. However, the residence time and flame surface area increased with higher expansion ratios.

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Mathematical Model for Adsorption of Berberine on Encapsulated Adsorbent (캡슬에 고정화된 흡착제에의 Berberine의 흡착에 관한 수학적 모델)

  • 최정우;조상원이원홍
    • KSBB Journal
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    • v.10 no.4
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    • pp.358-369
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    • 1995
  • A mathematical model using local thermodynamic equilibrium isotherms for adsorption in encapsulated adsorbent is proposed in order to optimize the design parameters in situ bioproduct separation process. The model accurately follows the experimental data on the adsorption of berberine, secondary metabolite produced in Thaictrum rugosum plant cell culture. The adsorption rate on encapsulated adsorbent is compared with that on alginate-entrapped adsorbent. The result shows that the higher loading capacity in encapsulated adsorbent is mainly due to the increase in the maximum solid phase concentration. Based on the adsorption rate and loading capacity, the encapsulated adsorbent would be more useful than the entrapped adsorbent when used in situ bioproduct separation process. Design parameters in situ bioproduct separation process, such as the size of the capsule, membrane thickness, the ratio of capsule volume to bulk volume, the ratio of single capsule volume to total capsule volume and the adsorbent content in the capsule, are evaluated by using the model. The ratio of single capsule volume to total capsule volume is the most effective parameter for adsorption of berberine on encapsulated adsorbent.

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Kinetics of Catalytic Reactions Occurring in a Small Reaction Volume (작은 반응 매질에서 일어나는 촉매 반응 속도에 관한 연구)

  • Kim, Jung-Han;Sung, Jae-Young
    • Journal of the Korean Chemical Society
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    • v.52 no.3
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    • pp.217-222
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    • 2008
  • We investigate the kinetics of diffusion-influenced catalytic reactions occurring in small reaction volume. From a simple exact model study, we find that the reaction rate coefficient decreases with the size of reaction volume. The explicit expression for the average reaction rate constant is presented, which can be regarded as a generalization of well-known Collins-Kimball rate constant into the reactions occurring in a small reaction volume. It turns out that the traditional diffusion influenced reaction dynamics is followed by a single exponential relaxation phase with a rate constant dependent on the reaction volume for the catalytic reactions occurring in small reaction volumes.

The influence of Brexit on Container Volume of Korea (브렉시트(Brexit)의 한국 컨테이너물동량에 대한 영향)

  • Choi, Bong-Ho;Lee, Gi-Whan
    • Journal of Korea Port Economic Association
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    • v.32 no.3
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    • pp.67-81
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    • 2016
  • This paper examines the influence of Brexit on container volume of Korea, especially of macroeconomic variables such as exchange rate and industrial production of EU and United Kingdom. To do this, we use monthly time series data during 2000-2016, and introduce the analysis method of cointegration test and VECM, and analyze the influence of industrial production and exchange rate of EU and U.K. on container volume of Korea. The results are as follows. First, the container volume of Korea is influenced by the exchange rate and industrial production of EU in the long run. But the exchange and industrial production of U.K. influenced on only export container volume of Korea, and the influence of U.K. macroeconomic variables on container volume of Korea was not large in the long lun. Second, In the shot run, the influence of exchange rate on container volume of Korea, especially on export container volume was significant in EU and U.K. To sum up, the influence of EU macroeconomic variables on container volume of Korea is larger than that of U.K., and the influence of exchange rate variable is more significant than that of industrial production variable.

Implementation of Automatic Microphone Volume Controller and Recognition Rate Improvement (자동 입력레벨 조절기의 구현 및 인식 성능 향상)

  • 김상진;한민수
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.503-506
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    • 2001
  • In this paper, we describe the implementation of a microphone input level control algorithm and the speech improvement with this level controller in personal computer environment. The volume of speech obtained through a microphone affects the speech recognition rate directly. Therefore, proper input volume level control is desired fur better recognition. We considered some conditions for the successful volume controller implementation firstly, then checked its usefulness on our speech recognition system with common office environment speech database. Cepstral mean subtraction is also utilized far the channel-effect compensation of the database. Our implemented controller achieved approximately 50% reduction, i.e., improvement in speech recognition error rate.

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Analysis of First Flushing Effects for the Vineyard Storm Runoff (강우시 포도밭에 대한 초기세척효과 분석)

  • Yoon, Young-Sam;Kwon, Hun-Gak;Lee, Jae-Woon;Yu, Jay-Jung;Lee, Jae-Kwan
    • Journal of Environmental Science International
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    • v.20 no.8
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    • pp.977-986
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    • 2011
  • This study analyzed the characteristics of stormwater runoff in the orchard areas and quantitatively estimated effluence of nonpoint source pollutants for the volume of runoff. Two target areas under vine cultivation were each $2,000m^2$ and $1,800m^2$, located in Gyeongju City. Since grape was the only crop on the target area, the characteristics of stormwater runoff at vineyard could be evaluated independently. A total of 51 rainfall events in the vineyard area during two years(2008-2009) was surveyed, and 19 of them became stormwater runoff, with rainfall ranging 16.5 - 79.7 mm and antecedent dry period of 1-13 days. The pollutant runoff loads by volume of stormwater runoff showed BOD ranging 19.5 - 45.3% in 30% of runoff volume. The average pollution discharge rate was 32.4%, indicating small first flush effect of BOD. The range of SS concentrations was 5 - 52.0% in 10% of runoff volume, showing the average 28.7% of discharge rate, about 3 times more than rainfall effluent. TOC and TN appeared to be similar to the results of BOD, the average discharge rate of 30.9% and 30.6% for TOC and TN, respectively, for 30% of stormwater runoff volume. Average discharge rate of COD and TP in the same runoff volume was 35.1% and 36%, respectively, showing comparatively high discharge ratio. As the targeted vineyard area was permeable land, the pollution load ratio against rainfall-runoff volume appeared to be 1:1, implying no strong first flush effect for all the survey items.

The Effects of Prolactin and Vasopressin on the Regulation of Amniotic Fluid Volume and Its $Na^{+}$ Concentration through the Membrane Surrounding Amniotic Fluid

  • Kim, Dong-Wook;Kim, Sang-Jeong;Sung, Ho-Kyung
    • The Korean Journal of Physiology
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    • v.29 no.1
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    • pp.81-89
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    • 1995
  • The effects of prolactin and vasopressin on the regulation of amniotic fluid (AF) volume and its $Na^{+}$ concentration $([Na^{+}])$ through the membrane surrounding the AF during increase in AF volume due to fetal urination were studied. About 70% of AF volume was replaced with normal isotonic saline solution. Isotonic saline solution (0.5 ml) containing Censored and LiCl was introduced into each amniotic sac. Vasopressin (25 ng/ml) or prolactin (1 mg/ml) of AF was then injected into experimental amniotic sac. The concentrations of Congored, $Li^{+}$, and $Na^{+}$ were measured at 30 and 60 min intervals after injection. Af samples with decreased Censored concentration ([CR]) during the period of 30 - 60 min were analyzed. The percentage change of $[Na^{+}]$ and the rate of $Li^{+}$ movement during this period were calculated, and the effects of vasopressin and prolactin on them were evaluated. Fellowing results were obtained: 1. The rate of reduction of [CR] in the AF was retarded by vasopressin or prolactin injection. 2. The rate of reduction of $[Li^{+}]$ in the AF was also retarded by vasopressin or prolactin injection. 3. The rate of reduction of $[Li^{+}]$ in the AF was less retarded by vasopressin than that of [CR]. 4. $[Na^{+}]$ changed to approach to the normal level, but this was markedly retarded by prolactin injection. 5. Direction of $Li^{+}$ movement was correlated with the change in $[Na^{+}]$ but it always moved out of the amniotic sac even when the $[Na^{+}]$ increased in vasopressin injected AF. From the above results, it is suggested that vasopressin in the AF triggers the fetus to urinate, and then the membranes surrounding the AF regulate osmolarity by efflux of $Na^{+}$. We suggest that prolactin facilitates water outflow across the amniotic membrane during increase in AF volume, in contrast to a constant volume, whereas regulation of $[Na^{+}]$ is partly restricted by prolactin.

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Effects of Initial Inoculum Size, Liquid Volume and Medium Feeding Strategy on Panax ginseng Hairy Roots Growth

  • Jeong, Gwi-Taek;Park, Don-Hui;Hwang, Baek
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.250-253
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    • 2000
  • We researched effects of growth on initial inoculum size, liquid volume, and medium feeding rate etc. Cell suspension inoculated at low cell concentrations showed a typical growth reduction, whereas root cultures showed an improvement in growth. In this paper, Hairy roots showed high growth rate at 0.4 % inoculum size and 100 mL liquid volume in 250 mL flask cultures.

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The Effects of Training on the Proper Use of Respiratory Rate Measurement Devices for Providing High-Quality Artificial Ventilation

  • Jae-Ran Lim;Sung-Hwan Bang;Hyo-Suk Song;Gyu-Sik Shim;Ho-Jin Park
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.3
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    • pp.165-171
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    • 2024
  • This study aims to investigate the appropriate volume of artificial ventilation and success rate when Basic - emergency medical Technician administer bag valve mask(BVM) artificial ventilation to patients experiencing respiratory failure or respiratory arrest using a respiratory rate measurement device. The research was conducted from December 11th to 12th, 2023, targeting 20 Basic - emergency medical Technicians enrolled at D University. Ten participants were selected for the experimental group, receiving BVM ventilation training with the use of a respiratory rate measurement device, while the other ten were assigned to the control group, receiving BVM ventilation training without the use of a respiratory rate measurement device. The experiment involved providing artificial ventilation for 2 minutes. The results of the study indicated that the control group did not provide accurate tidal volume (p=.025). The experimental group demonstrated a higher success rate of ventilation over the 2-minute period, while the control group showed a significant difference (p=.001). Subjective perception of tidal volume and objectively measured tidal volume also exhibited a significant difference in the control group (p=.010). Therefore, training with a respiratory rate measurement device can align the subjective perception of tidal volume with objective measurements, increase the success rate of ventilation, and potentially contribute to improving survival rates in patients experiencing respiratory failure or respiratory arrest during cardiopulmonary resuscitation.

Calculation of Smoke Temperature/Volume Folw rate in Tunnel Fires (철도터널에서의 화재시 발생되는 연기 온도/발생량 계산)

  • Park, Won-Hee;Jang, Yong-Jun
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1218-1222
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    • 2007
  • Under various tunnel fires, smoke average temperature and volume flow rate in a tunnel fire are calculated. To obtain realistic results, enthalpy of smoke which composites combustion gases and entrainment air is calculated from curvefit polynomials by temperature.

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