• Title/Summary/Keyword: flow control

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A Determination Method of a Rainwater Retention-Pumping System Combination for Runoff Control from Building Roof Area (지붕면 유출제어를 위한 빗물의 저장-펌프 시스템 조합 결정방안)

  • Kim, Young-Jin;Han, Moo-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.495-499
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    • 2008
  • This study developed a determination method for a rainwater retention-pumping combination system for roof runoff control. The outflow and stored water volume in the rainwater system was simulated using a water balance equation. Its result is presented in the TPP (Tank capcity-Peak outflow-Pumping rate) curves for rainfall return periods. In a case study on reduction of the peak flow rate of 100-year return period to 5-year in Seoul, The range of pumping rate for $100m^2$ roof area is determined as $0{\sim}25{\ell}$/min. Additionally, retention volume of $8.5{\sim}10m^3$ can be combined with the pumping rate range. That is to say an effective combination of a retention-pumping system capacity can be determined from a system of $8.5m^3$ tank with $25{\ell}$/min to $10m^3$ tank without pump. Using the TPP curves, engineers can determine the effective combination range of retention & pumping system capacity. Furthermore, that can be helpful to decide a detail system capacity for field condition.

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An Experimental Study on the Rheological Properties of the Combined Self-Compacting Concrete by Quality Variations (품질변동에 따른 병용계 자기충전 콘크리트의 유동특성에 관한 실험적 연구)

  • Kwon, Yeong-Ho
    • Journal of the Korea Concrete Institute
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    • v.26 no.3
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    • pp.277-285
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    • 2014
  • The purpose of this study is to investigate experimentally the variation factors range having influence on the rheological properties of the combined self-compacting concrete according to materials quality, weighting error and site conditions. Two types cement (blast-furnace slag cement and belite cement), lime stone powder as binder and the optimum mix proportions in the preceded study are selected for this study. Also, variations for sensitivity test are as followings; (1) Concrete temperature 3 cases (2) Surface moisture of sand 5cases (3) Fineness modulus of sand 5cases (4) Specific surface of lime stone powder 3cases (5) Dosage of chemical admixture 5cases. Slump flow ($650{\pm}50mm$), 500 mm reaching time (($7{\pm}3sec$), V-type flowing time ($15{\pm}5sec$) and U-box height (min. 300 mm) are tested for sensitivity. As test results, the variations range for quality control are as followings. (1) Concrete temperature; $10{\sim}20^{\circ}C$(below $30^{\circ}C$) (2) Surface moisture of sand; $base{\pm}0.6%$ (3) Fineness modulus of sand; $2.6{\pm}0.2$ (4) Dosage of chemical admixture; $base{\pm}0.2%$ (5) Specific surface of lime stone powder $6000cm^2/g$. Compared with two types cement including based belite cement (binary type) and based slag cement (ternary type), the combined self-compacting concrete used belite cement type is most stable in the quality control because of high contents for lime stone powder and $C_2S$. It is to propose a control scheme of the combined self-compacting concrete in the actual construction work.

Polybrominated Diphenyl Ethers Orally Administration to Mice Were Tansferred to Offspring during Gestation and Lactation with Disruptions on the Immune System

  • Hong, Soon-Keun;Sohn, Kyung-Hee;Kim, In-Young;Lee, Jong-Kwon;Ju, Jung-Hun;Kim, Jin-Ho;Lim, Chae-Hyung;Han, Beom-Seok;Jung, Hwa-Chul;Lee, Jin-Yong;Park, Kui-Lea
    • IMMUNE NETWORK
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    • v.10 no.2
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    • pp.64-74
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    • 2010
  • Background: The present study was undertaken to examine the immunological effects of pentabrominated diphenyl ether (penta-BDE) and decabrominated diphenyl ether (deca-BDE) on the immune system of the dams and the developmental immune system of the offsprings. Methods: In this study, mated female C57BL/6J mice were orally administered penta-BDE, deca-BDE or corn oil for 5 weeks, from gestational day 6 to lactational day 21. Results: The body weight of PND21 exposed to penta-BDE was significantly decreased relative to control mice, but that of post-natal day 63 (PND63) were recovered. Orally dosed dams with penta-BDE had significantly smaller absolute and relative spleen masses than control mice. Absolute and relative spleen and thymus masses of PND21 exposed to penta-BDE were significantly decreased over control. The exposure of dams and PND21 with penta-BDE reduced the number of splenocytes and thymocytes. As results of hematologic analysis, percentage WBC and percentage neutrophils increased in dams with deca-BDE. Splenic T cell proliferation in dams and PND21 exposed to penta-BDE was increased, and there were no significant difference in splenic B cell proliferation in all treatment groups. As results of flow cytometric analysis of splenocyte, percentage total T cell, Th cell and Tc cell in PND21 exposed to penta-BDE was slightly increased, and percentage macrophage in dams and PND21 exposed to deca-BDE was decreased. The ELISA results of antibody production show no significant difference in all treatment groups relative to controls. Conclusion: These results imply that PBDEs given to the dam were transferred to the offspring during gestation and lactation, and PBDEs transferred from the dam affect immune system of offspring.

The Experimental Study of Sunkihwalhyul-Tang against Inhibitive Effects on the Brain Ischemia (순기활혈탕(順氣活血湯)의 뇌허혈(腦虛血) 억제효과(抑制效果)에 관한 실험적(實驗的) 연구(硏究))

  • Hong, Seok;Ann, Jeong-Jo;Jeong, Sang-Yoon;Choi, Chang-Won;Jeong, Young-Deuk
    • Herbal Formula Science
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    • v.13 no.1
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    • pp.49-69
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    • 2005
  • This Study was designed to investigate the effect of Sunkihwalhyul -Tang extract(SHT) on the change of cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD) and mean arterial blood pressure(MABP)] in normal and cerebral ischemic rats, and further to determine the mechanisms of action of SHT on hemodynamics. In addition, this study was designed to investigate whether SHT inhibits lactate dehydrog enase(LDH) activity in neuronal cells and cytokines production in serum of cerebral ischemic rats. The results were as follows 1. SHT significantly increased rCBF and PAD in a dose-dependent manner, but MABP was not changed by injecting SHT. These results suggest that SHT significantly increases rCBF by dilating PAD. 2. The SHT-induced increase in rCBF was significantly inhibited by pretreatment with indomethacin(IDN, 1 mg/kg, i.p.), an inhibitor of cyclooxygenase and methylene blue(MTB, $10{\mu}g/kg$, i.p.), an inhibitor of guanylate cyclase. 3. The SHT-induced dilation in PAD was significantly inhibited by pretreatment with IDN and MTB. 4. The SHT-induced some increase in MABP was significantly increased by pretreatment with IDN. These results suggest that the mechanism of action of SBT is mediated by guanylate cyclase. 5. Both rCBF and PAD were significantly and stably increased by SHT(10 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. 6. SBH significantly inhibited LDH activity in neuronal cells. These results suggest that SHT prevents the neuronal death. 7. In cytokine production in the senlm drawn from femoral artery 1 hr after middlecerebral arterial occlusion, sample group showed significantly decreased production of IL-1$\beta$ production, decreased production TNF-$\alpha$ and increased Production of IL-10 compared with control group. 8. In cytokine production in the serum drawn femoral artery 1 hr after reperfusion, sample group showed significantly decreased production of IL-1$\beta$ and TNF-$\alpha$ as wellas significantly increased production of IL10 compared with control group. These results suggest that SHT mediated by guanylate cyclase has inhibitive effect on the brain damage by inhibiting LDH activity, IL-1$\beta$ and TNF-$\alpha$ production, and by accelerating IL-10 production. The present author thinks that SHT has an anti-ischemic effects through the improvement of cerebral hemodynamics and inhibitive enects on the brain damage.

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Optimal Cultivar Selection of Kohlrabi for Hydroponics Culture in a Closed-type Plant Factory System (완전제어형 식물공장내 수경재배용 콜라비 품종 선발)

  • Uoon, Chan-Il;Cha, Mi-Kyung;Jeon, Yoon-A;Cho, Young-Yeol
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.297-300
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    • 2017
  • Plant factory can control artificially the environments for crop cultivation, so they can produce high quality agricultural products all year round. This study was carried to select suitable kohlrabi cultivar for hydroponics in a closed-type plant factory system. We used three cultivars of red kohlrabi, 'Asac kohl', 'Kolibri', and 'Purple king' as plant materials. The artificial light source was LED light, light intensity and photoperiod were $249{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and 12/12 hours (day/night period), respectively. Hydroponic cultivation type was used circulating deep flow technique. At 43 days after transplanting, fresh weight of whole plant and tuber and leaf area were not significantly different among cultivars. Shoot dry weight and tuber dry weight were highest in 'Asac kohl' cultivar, and number of leaves was highest in 'Purple king' cultivar. Sugar content and yield were highest in 'Asac kohl' cultivar. Considering the growth and marketable yields, 'Asac kohl' was the optimal kohlrabi cultivar for hydroponic cultivation in a closed-type plant factory system.

Radiosensitization Effect of Overexpression of Adenovirus-mediated SIRT6 on A549 Non-small Cell Lung Cancer Cells

  • Cai, Yong;Sheng, Zhao-Ying;Liang, Shi-Xiong
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.17
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    • pp.7297-7301
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    • 2014
  • Objective: To explore the radiosensitization effect of overexpression of silent information regulator 6 (SIRT6) on A549 non-small cell lung cancer (NSCLC) cells. Methods: Adenovirus vector Ad-SIRT6 causing overexpression of SIRT6 was established. Western blotting and MTT assay were adopted to detect the level of SIRT6 protein and the inhibitory rate of A549 cell proliferation after different concentrations of adenovirus transduction (0, 25, 100, 200, and 400 pfu/cell) for 24 h. Control group, Ad-null group and Ad-SIRT6 group were designed in this experiment and virus concentration of the latter two groups was 200 pfu/cell. Colony formation assays were employed to test survival fraction (SF) of the 3 groups after 0, 2, 4, 6, 8, 10 X-ray irradiation. Flow cytometry was used to detect the status of cell cycle of 3 groups after 48 h of 4Gy X-ray irradiation and Western blotting was used to determine the expression of apoptosis-related genes of 3 groups after 48 h of 4GyX-ray irradiation. Results: In the range of 25~400 pfu/cell, the inhibitory rate of A549 cell proliferation increased as adenovirus concentration raised. The inhibitory rates under the concentrations of 0, 25, 100, 200, and 400 pfu/cell were 0%, $4.23{\pm}0.34%$, $12.7{\pm}2.57%$, $22.6{\pm}3.38%$, $32.2{\pm}3.22%$, $38.7{\pm}4.09%$ and $47.8{\pm}5.58%$ and there were significantly differences among groups (P<0.05). SF in Ad-SIRT6 group was lower than Ad-null and control groups after 4~10Gy X-ray irradiation (P<0.05) and the sensitization enhancement ratio (SER) was 1.35 when compared with control group. Moreover, after 48 h of 4Gy X-ray irradiation, there appeared a significant increase in G1-phase cell proportion, upregulated expression of the level of apoptosis-promoting genes (Bax and Cleaved caspase-3), but a obvious decline in S-phase and G2-phase cell proportion and a significant decrease of the level of apoptosis-inhibiting gene (Bal-2) in the Ad-SIRT6 group (P<0.05). Conclusion: The over-expression of adenovirus-mediated SIRT6, which has radiosensitization effect on A549 cells of NSCLC, can inhibit the proliferation of A549 cells and cause G0/G1 phase retardation as well as induce apoptosis of cells.

Effects of Cell Cycle Regulators on the Cell Cycle Synchronization of Porcine induced Pluripotent Stem Cells

  • Kwon, Dae-Jin;Hwang, In-Sul;Kwak, Tae-Uk;Yang, Hyeon;Park, Mi-Ryung;Ock, Sun-A;Oh, Keon Bong;Woo, Jae-Seok;Im, Gi-Sun;Hwang, Seongsoo
    • Development and Reproduction
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    • v.21 no.1
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    • pp.47-54
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    • 2017
  • Unlike mouse results, cloning efficiency of nuclear transfer from porcine induced pluripotent stem cells (piPSCs) is very low. The present study was performed to investigate the effect of cell cycle inhibitors on the cell cycle synchronization of piPSCs. piPSCs were generated using combination of six human transcriptional factors under stem cell culture condition. To examine the efficiency of cell cycle synchronization, piPSCs were cultured on a matrigel coated plate with stem cell media and they were treated with staurosporine (STA, 20 nM), daidzein (DAI, $100{\mu}M$), roscovitine (ROSC, $10{\mu}M$), or olomoucine (OLO, $200{\mu}M$) for 12 h. Flow Cytometry (FACs) data showed that piPSCs in control were in G1 ($37.5{\pm}0.2%$), S ($34.0{\pm}0.6%$) and G2/M ($28.5{\pm}0.4%$). The proportion of cells at G1 in DAI group was significantly higher than that in control, while STA, ROSC and OLO treatments could not block the cell cycle of piPSCs. Both of viability and apoptosis were affected by STA and ROSC treatment, but there were no significantly differences between control and DAI groups. Real-Time qPCR and FACs results revealed that DAI treatment did not affect the expression of pluripotent gene, Oct4. In case of OLO, it did not affect both of viability and apoptosis, but Oct4 expression was significantly decreased. Our results suggest that DAI could be used for synchronizing piPSCs at G1 stage and has any deleterious effect on survival and pluripotency sustaining of piPSCs.

Hydrogeochemical study of a watershed in Pocheon area: controls of water chemistry

  • Kim, Kyoung-Ho;Yun, Seong-Taek;Chae, Soo-Ho;Jean, Jong-Wook;Lee, Jeong-Ho;Kweon, Hae-Woo
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.121-121
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    • 2004
  • The groundwater in the Pocheon area occurs from both a fractured bedrock aquifer in igneous and metamorphic rocks and an alluvial aquifer with a thickness of <50 m, and forms a major source of domestic and agricultural water supply. In this study, we performed a hydrogeochemical study in order to identify the control of geochemical processes on groundwater quality. For this study, groundwater level and physicochemical parameters (EC, Eh, pH, alkalinity) were monitored once a month from a total of 150 groundwater wells between June 2003 to August 2004. A total of 153 water samples (13 surface water, 66 alluvial groundwater, 74 bedrock groundwater) were also collected and analyzed in February 2004. Groundwater chemistry in the study area is very complex, depending on a number of major factors such as geology, degree of chemical weathering, and quality of recharge water. Hydrochemical reactions such as the leaching of surficial and near-solace soil salts, dissolution of calcite, cation exchange, and weathering of silicate minerals are proposed to explain the chemistry of natural groundwater. Alluvial groundwaters locally have very high TDS concentrations, which are characterized by their chloride(nitrate)-sulfate-bicabonate facies and low Na/Cl ratio. Their grondwater levels are highly fluctuated according to rainfall event. We suggest that high nitrate content and salinity in such alluvial groundwaters originates from the local recharge of sewage effluents and/or fertilizers. Likewise, high concentrations of nitrate were also locally observed in some bedrock groundwaters, suggesting their effect of anthropogenic contamination. This is possibly due to the bypass flow taking place through macropores. Tile degree of the weathering of silicate minerals seems to be a major control of the distribution of major cations (sodium, calcium, magnesium, potassium) in bedrock groundwaters, which show a general increase with increasing depth of wells. Thermodynamic interpretation of groundwater chemistry shows that the groundwater in the study area is in chemical equilibrium with kaolinite and Na-montmorillonite, which indicates that weathering of plagioclase to those minerals is a major control of hydrochemistry of bedrock groundwater. The interpretation of the molar ratios among major ions, as well as the mass balance calculation, also indicates the role of both dissolution/precipitation of calcite and Ca-Na cationic exchange as bedrock groundwaters evolves progressively.

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Angiogenic Responce to Transmyocardial Mechanical Reveascularization(TMMR) with Polymer Myocardial Stent (고분자 중합체 심근 스템트를 이용한 기계적 경심근 혈류재건술의 혈관생성 반응)

  • Choi, Ho;Lee, Cheol-Joo;Moon, Kwang-Deok;Kim, Young-Jin;Kang, Joon-Kyu;Hong, Jun-Wha;Jee, Kyung-Soo;Han, Man-Jung;Cho, Sang-Ho
    • Journal of Chest Surgery
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    • v.33 no.6
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    • pp.494-501
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    • 2000
  • Background: Transmyocardial laser revascularization(TMLR) for revascularizing ischemic myocardium in patients was originally based on the assumption that laser channels remain their patency much longer. But recent studies show that laser channels did not remain open and that TMLR could achieve treatment benefits without long-term channel patency. The angiongencesis is currently thought to be induced by non-specific inflammatory response to mechanical tissue injury. This study is to evaluate hypothesis that various transmyocaridal mechanical revascularization(TMMR) may induce the angiogenic responses similar to that seen with TMLR, and transmyocaridal polymer stent revascularization(TMSR), the polymer stent in the myocardial tissue is hydrolyzed in 2 weeks, may enhance the non-specific inflammatory reaction resulting angiogenesis. Furthermore, polymer myocaridal stent channels remain long-term patency. Material and Method: Eight domestic pigs underwent ligation of the proximal circumflex artery, and 2 weeks later they were randomized to undergo transmycardial acupunctural revascularization (TMPR, Group I) of the left lateral wall with 18-G needle(n=2), to undergo transmyocardial (TMDR, Group II) with industrial 2mm steel drill(n=2), to undergo transmyocardial polymer stent revascularization (TMSR, Group III) after drilling the infarcted myocardium(n=2), the stent is poly(lactic acid-co-glycolic acid), which is self-degradated in the myocardium, and to a control group the ischemic zone was unterated(n=2). All the pigs were sacrificed after 4 weeks TMMR. Sections from the ischemic zone were submitted for vascular endothelial growth factor (VEGF) ELISA and histology. Result: There were makedly increase in the VEGF immunoassay in the ischemic zone of the TMMR group compared to the ischemic zone of the control group(control: each 30.85 and 43.15pg/mg protein, TMPR: each 44.14 and 68.61 pg/mg protein, TMDR: each 65.92 and 78.65 pg/mg protein, TMSR: each 177.39 and 168.87 pg/mg protein). TMSR channels caused greatest VEGF expression than channels made by other group and the polymer stent channels remained vacuole after 4 weeks. Conclusion: Transmyocardial polymer stent revascularization promoted the most angiogenci response by the VEGF immunoassay, although our study did not show the statistical significancy. The channels remained but the flow patency was not verified. Transmyocardial polymer stent revascularization (TMSR) is desirable in future experimental trials and in view of the significant cost implications comparable to that of laser.

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Characteristics of domestic coals and efficient control of coal dust (국내 석탄광 분진의 특성과 효율적 제어)

  • Kim, Soo Hong;Kwon, Jun Wook;Kim, Sun Myung;Kim, Yun kwang;Jang, Yun Ho
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.4
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    • pp.589-609
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    • 2017
  • This study carried out the density and energy dispersive X-ray spectroscopy and particle size analysis which are the physical characteristics of coal dust by collecting samples of coal dust in the five domestic mines to control the coal dust through ventilation in the workplace for coal mining in the country. This will contribute to a more comfortable working environment by understanding the physical characteristics of the coal dust which is derived from any hard coal produced domestically. In particular, the result of PSA analysis showed that the size of coal dust sample for this study ranged from $0.007{\sim}88.614{\mu}m$ were the particles less than $3.5{\mu}m$, the size range responsible for pneumoconiosis. To observe the flow of coal dust collected on the wind speed, the fallout of coal dust produced by the wind tunnel for the wind was measured and the particle size analysis of coal dust fallout was carried out. In addition, airborne dust is measured according to the mine velocity by using a multi-stage Anderson sampler in the mine where fine dust is generated in a large amount and the wind speed is found out to control the coal dust below $3.5{\mu}m$. In addition, natural ventilation pressure of A mine was calculated to prevent over design of the main fan.