• Title/Summary/Keyword: W/S Ratio

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An Experimental Study on the Properties of Engineering and Shrinkage Cracking Reduction of Fiber Reinforced Concrete Using Recycled Fine Aggregate (섬유보강 순환잔골재 콘크리트의 공학적 특성 및 수축균열저감특성에 관한 실험적 연구)

  • Kim, Gyu-Yong;Nam, Jeong-Soo;Kim, Moo-Han;Lee, Do-Heun;Song, Ha-Young
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.3
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    • pp.82-89
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    • 2009
  • Recently, the study is progressing actively about manufacture skill of concrete for promoted recycled aggregate and concrete made into recycled aggregate in the construction production field. But, application and study about recycled fine aggregate insufficient compared to recycled coarse aggregate. So, in this study, it presents basic data for development of environmental load reduction fiber reinforcement recycled fine aggregate concrete by comparison and investigation about engineering properties and shrinkage cracking of fiber reinforcement recycled find aggregate concrete for increasing shrinkage cracking reduction and long term stability of environmental load reduction concrete used recycled fine aggregate. In the result of the study, compared to natural fine aggregate, a crack-extent increased by applying recycled fine aggregate, moreover, as a water cement ratio increased, the crack size increased, as well. In addition, it's shown that the specimen mixed with PVA and Nylon, among all kinds of fibers, showed the smallest crack size, so it's verified that the mix of fiber had an effect on decreasing crack-extent.

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In situ ruminal degradation characteristics of dry matter and crude protein from dried corn, high-protein corn, and wheat distillers grains

  • Lee, Y.H.;Ahmadi, F.;Choi, D.Y.;Kwak, W.S.
    • Journal of Animal Science and Technology
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    • v.58 no.9
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    • pp.33.1-33.7
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    • 2016
  • Background: The continuing growth of the ethanol industry has generated large amounts of various distillers grains co-products. These are characterized by a wide variation in chemical composition and ruminal degradability. Therefore, their precise formulation in the ruminant diet requires the systematic evaluation of their degradation profiles in the rumen. Methods: Three distillers grains plus soluble co-products (DDGS) namely, corn DDGS, high-protein corn DDGS (HP-DDGS), and wheat DDGS, were subjected to an in situ trial to determine the degradation kinetics of the dry matter (DM) and crude protein (CP). Soybean meal (SBM), a feed with highly degradable protein in the rumen, was included as the fourth feed. The four feeds were incubated in duplicate at each time point in the rumen of three ruminally cannulated Hanwoo cattle for 1, 2, 4, 6, 8, 12, 24, and 48 h. Results: Wheat DDGS had the highest filterable and soluble A fraction of its DM (37.2 %), but the lowest degradable B (49.5 %; P < 0.001) and an undegradable C fraction (13.3 %; P < 0.001). The filterable and soluble A fraction of CP was greatest with wheat DDGS, intermediate with corn DDGS, and lowest with HP-DDGS and SBM; however, the undegradable C fraction of CP was the greatest with HP-DDGS (41.2 %), intermediate with corn DDGS (2.7 %), and lowest with wheat DDGS and SMB (average 4.3 %). The degradation rate of degradable B fraction ($%\;h^{-1}$) was ranked from highest to lowest as follows for 1) DM: SBM (13.3), wheat DDGS (9.1), and corn DDGS and HP-DDGS (average 5.2); 2) CP: SBM (17.6), wheat DDGS (11.6), and corn DDGS and HP-DDGS (average 4.4). The in situ effective degradability of CP, assuming a passage rate of $0.06h^{-1}$, was the highest (P < 0.001) for SBM (73.9 %) and wheat DDGS (71.2 %), intermediate for corn DDGS (42.5 %), and the lowest for HP-DDGS (28.6 %), which suggests that corn DDGS and HP-DDGS are a good source of undegraded intake protein for ruminants. Conclusions: This study provided a comparative estimate of ruminal DM and CP degradation characteristics for three DDGS co-products and SBM, which might be useful for their inclusion in the diet according to the ruminally undegraded to degraded intake protein ratio.

Effect of Yijin-tang on Gastric Motility between Normal Intact and Partial Pyloric Obstructed Rats (이진탕(二陳湯)이 정상 및 위 유문부가 부분폐색된 흰 쥐의 위 운동성에 미치는 효과)

  • Han, Soak-Young;Yoon, Sang-Hyub
    • The Journal of Internal Korean Medicine
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    • v.30 no.1
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    • pp.107-118
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    • 2009
  • Objectives : This study was aimed to investigated the effect of Yijin-tang on gastric motility and its mechanism of action in normal intact and partial pyloric obstructed rats. Methods : Gastric emptying was measured by the number of glass beads expelled from the stomach (containing one hundred of glass beads. ${\phi}1mm$) in 1 hour or 2 hours after glass beads and test drugs (normal saline. Yijin-tang 90mg/kg. Yijin-tang 270mg/kg) administration in normal intact and partial pyloric obstructed rats. In another series of experiments to evaluate the mechanism of Yijin-tang 270mg/kg under delayed conditions, normal intact rats were treated with atropine sulfate (1mg/kg,s.c.), cisplatin (10mg/kg,i.p.), quinpirole HCI (0.3mg/kg,i.p.) and NAME (NG-nitro-L-arginine methyl ester. 75mg/ kg,s.c.), respectively. Partial pyloric obstructed rats were modified by wrapping the nonabsorbable rubber ring (D :6mm, W:4mm, T: 1mm) around the 1st portion of the duodenum for 8 weeks. The myoelectrical activity of the gastric smooth muscle was recorded by a bipolar electrode placed at the abdominal surface in normal intact and partial pyloric obstructed rats. The gastric myoelectrical activity was measured for 30 minutes before and after orogastric administration of each solution (normal saline, Yijin-tang 270mg/kg) and expressed as dominant frequency, percent of normogastria and power ratio. Results : Yijin-tang improved gastric emptying more than normal saline in normal intact(p<0.001) and partial pyloric obstructed rats(p=0.002). Under the delayed gastric emptying induced by atropine sulfate, cisplatin, quinpirole HCI and NAME. Yijin-tang enhanced gastric emptying significantly in the cisplatin treated group(p<0.001). but didn't in other treated groups. Administration of Yijin-tang 270mg/kg has no significant effect on the myoelectrical activity of the gastric smooth muscle in both normal intact rats and partial pyloric obstructed rats. Conclusions : Yijin-tang seems to stimulate the gastric motility through suppressing the 5HT3 receptor and promoting the antroduodenal flow. We expect that Yijin-tang would be effective especially in dysmotility-like functional dyspepsia with partial pyloric obstruction or the side effects of cisplatin such as nausea, vomiting, abdominal discomfort, and delay of gastric emptying.

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Effect of Artificial Granular Zeolite(AGZ) on Purification of Heavy Metals in Wastewater and Alleviation or Rice Seeding Growth Damage (입상 인공제올라이트를 이용한 중금속 폐수 정화와 벼 유묘 생육장해 경감)

  • Lee, Deog-Bae;Lee, Kyeong-Bo;Lee, Sang-Bok;Kim, Jae-Duk;Henmi, Teruo
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.4
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    • pp.446-451
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    • 1999
  • This study was carried out to investigate some mineralogical characteristics of Artificial Granular Zeolite (AGZ) and effect of AGZ on purification and alleviation of rice seedling damages of mine wastewater containing heavy metals. AGZ had mainly representative Na-P1 peaks and some $C_3S$ peaks of Portland cement in X-ray diffractogram. Differential thermal analysis represented that AGZ had weak endothermic peak around $130^{\circ}C$ and new deep endothermic peak around $750^{\circ}C$ as compared to powdery artificial zeolite. The ranking of heavy metals removals by AGZ, was lead> copper> cadmium> zinc in the synthetic wastewater. Root growth of rice seedling was greatly inhibited in the mine wastewater, and died after all. As AGZ treated into the mine wastewater with the ratio 1 : 50 (W : V) for one day or 1 : 100 for 4 days, the concentrations of heavy metals in the mine wastewater were decreased to below the critical concentration for agricultural use. And rice seedlings were grew with little damages in the purified water by AGZ.

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The Slow Strain Rate Dependence of Zircaloy-4 Cladding Tube in Iodine Atmosphere (I) (요드분위기에서 지르칼로이 피복재의 저변형율속도 의존성(I))

  • Choi, Y.;Kang, Y.H.;Ryu, W.S.;Rim, C.S.
    • Nuclear Engineering and Technology
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    • v.17 no.3
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    • pp.211-215
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    • 1985
  • The effects of temperature and strain rate on the I-SCC behaviors of Zircaloy-4 were investigated by constant load test at 30$0^{\circ}C$ and constant elongation rate test at 300, 350 and 40$0^{\circ}C$ in 3.34mg $I_2$/㎤. The results showed that I-SCC susceptibility increased as the strain rate decreased or the temperature increased. The empirical relation between the stress and the time to failure at 30$0^{\circ}C$ was given by 1/ $t_{f}$∝exp (0.3$\sigma$/$\sigma$$_{UTS}$-31.5) When the I-SCC susceptibility was expressed by the ratio of fracture energy in iodine atmosphere to that in the inert atmosphere, severe I-SCC susceptibility was found near 7.6$\times$10$^{-6}$ sec at 30$0^{\circ}C$ and the maximum point of I-SCC susceptibility tended to shift to the higher strain rate with increasing the temperature. The quasi-cleavage fracture was observed in I-SCC fracture surface. From these results, it was certain that the film repture step was involved as an important process in the I-SCC mechanism of Zircaloy-4.4.

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Effects of Velocity Structures on Tracer Mixing in a Meandering Channel (사행수로에서 유속구조가 추적물질의 혼합에 미치는 영향)

  • Seo, Il Won;Park, Sung Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.1B
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    • pp.35-45
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    • 2009
  • In this study, a laboratory experiment has been performed on a S-curved channel with two curved sections. In the experiments, effects of 3-D velocity structures on mixing characteristics of tracer material were investigated. As a result, it was clearly noticed that the primary flow travels taking the shortest course of the meandering channel and has a very ununiform distribution at the bends. The secondary cell which was developing at the first bend disappears at the crossover, and then, at the next bend, secondary cell is re-developing in the opposite direction. The experimental results show that mixing of tracer is significantly affected by the combined action of ununiform primary flow and secondary cell. The ununiform primary flow separates the tracer cloud in the longitudinal direction, and the secondary cell further separates the retarding tracer cloud mainly in the transverse direction. As a result, these complex flow structures cause separation and spreading of tracer cloud both in the longitudinal and in the transverse directions. The measured dimensionless transverse dispersion coefficients calculated using 2-D routing procedure ranges 0.012-0.875, and is generally proportional to width to depth ratio (W/h). The predicted values calculated by the theoretical equation overestimate slightly the measured transverse dispersion coefficients.

Assessing the Necessity of Extra Reduction Aides in Intramedullary Nailing of Intertrochanteric Hip Fractures

  • John W. Yurek;Nikki A. Doerr;Alex Tang;Adam S. Kohring;Frank A. Liporace;Richard S. Yoon
    • Hip & pelvis
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    • v.35 no.3
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    • pp.183-192
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    • 2023
  • Purpose: This study aims to determine which intertrochanteric (IT) hip fracture and patient characteristics predict the necessity for adjunct reduction aides prior to prep and drape aiming for a more efficient surgery. Materials and Methods: Institutional fracture registries from two academic medical centers from 2017-2022 were analyzed. Data on patient demographics, comorbidities, fracture patterns identified on radiographs including displacement of the lesser trochanter (LT), thin lateral wall (LW), reverse obliquity (RO), subtrochanteric extension (STE), and number of fracture parts were collected, and the need for additional aides following traction on fracture table were collected. Fractures were classified using the AO/OTA classification. Regression analyses identified significant risk factors for needing extra reduction aides. Results: Of the 166 patients included, the average age was 80.84±12.7 years and BMI was 24.37±5.3 kg/m2. Univariate regression revealed increased irreducibility risk associated with RO (odds ratio [OR] 27.917, P≤0.001), LW (OR 24.882, P<0.001), and STE (OR 5.255, P=0.005). Multivariate analysis significantly correlated RO (OR 120.74, P<0.001) and thin LW (OR 131.14, P<0.001) with increased risk. However, STE (P=0.36) and LT displacement (P=0.77) weren't significant. Fracture types 2.2, 3.2, and 3.3 displayed elevated risk (P<0.001), while no other factors increased risk. Conclusion: Elderly patients with IT fractures with RO and/or thin LW are at higher risk of irreducibility, necessitating adjunct reduction aides. Other parameters showed no significant association, suggesting most fracture patterns can be achieved with traction manipulation alone.

Desalination of Boiled Oyster Extract by Electrodialysis (전기투석에 의한 굴자숙액의 탈염 특성)

  • 박표잠;이상훈;김세권
    • KSBB Journal
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    • v.15 no.2
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    • pp.167-173
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    • 2000
  • For selective elimination of salt from boiled oyster extract (BOE), electrodialyzer was used and the desalination conditions of B BOE were investigated. The ion-exchange membrane with a molecular weight cut off 100 Da was used for desalting of B BOE. The desalination efficiency at pH 4.0 was 13% higher than that at pH 9.0 when BOE was desalted for 90min. The e electrodialysis pro$\infty$ss could remove above 90% of the initial salt content when 5% BOE was desalted at pH 5.62 for 1 100min. The initial volume and concentration of permeation solution did not have significant effects on desalination time and r ratio. The important factors for the desalination of BOE were found to be pH and concentration of BOE. The results obtained prove that electrodialysis is a practical solution to the problem of selective elimination of salt from BOE.

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Effect of Combined Extract of Safflower Seed with Herbs on Blood Glucose Level and Biochemical Parameters in Streptozotocin-induced Diabetic Rats (홍화씨와 한약재 흔합추출물이 Streptozotocin으로 유도한 흰쥐의 혈당과 혈액 성분에 미치는 영향)

  • Yang, Kyung-Mi;Shin, Seung-Ryeul;Jang, Joung-Hyeon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.2
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    • pp.150-157
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    • 2006
  • The aim of the present study was to investigate the effect of combined extract of safflower seed with herbs on the improvement of blood glucose, lipid peroxides, lipids in the plasma and liver of strpetozotocin-induced diabetic rats. Rats in the experimental group were orally administered with combined extract of safflower seed (100 mg, 200 mg/kg B.W.) with herbs (Ophiopogon japonicus Ker-Gaqler, Glycyrrhiza uralensis Fisch, Mori Folium, Poria cocos, Rehmannia glutinosa, Eriobtrya japonica, Aralia continentalis Kitagawa, Zizyphus jujuba var, Cornus officinalis, Paeonia suffruticosa, Trichosanthes kirilowii Maxim and Schizandra chinensis Baill) for 4 weeks. Body weight gain and food efficiency ratio were significantly lower in diabetic groups than those of control group. These were no protective effect of the supplementation of combined extract of safflower seed with herbs. Concentration of blood glucose was significantly higher in the diabetic groups than those in the control group. Blood glucose concentration was remarkably lower supplementation of combined extract of safflower seed (200 mg/kg B.W.) with herbs. There was no significant difference of plasma lipid peroxides among experimental groups, while liver lipid peroxides of diabetic group was significantly higher in control group. But supplementation of combined extract of safflower seed with herbs was induced markedly lower in liver lipid peroxides in diabetic rats. Diabetic groups had markedly higher levels in triglycerides, LDL-cholesterol and atherogenic index, while had lower HDL-cholesterol level. Triglyceride levels of plasma and liver were significantly lower with combined extract of safflower seed with herbs. But total cholesterol, phospholipid and free fatty acid were no differing significantly among experimental groups.

Effects of Single or Mixed Supplements of Plant Extract, Fermented Medicinal Plants and Lactobacillus on Growth Performance in Broilers (식물 추출물, 한방 발효물, 유산균의 단독 및 혼합 첨가 급여가 육계 생산성에 미치는 영향)

  • Kim, D.W.;Kim, S.H.;Yu, D.J.;Kang, G.H.;Kim, J.H.;Kang, H.G.;Jang, B.G.;Na, J.C.;Suh, O.S.;Jang, I.S.;Lee, K.H.
    • Korean Journal of Poultry Science
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    • v.34 no.3
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    • pp.187-196
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    • 2007
  • This experiment was conducted to investigate the effect of dietary single or mixed supplementation of plant extract, fermented medicinal plants and Lactobacillus on performance, nutrient availability, blood characteristics, cecal microflora and intestinal digestive enzymes activity in broiler chickens and to prove the possibility of plant derived compounds and Lactobacillus as an antibiotic growth promoter alternative. A total of eight hundred forty, 1-d-old male broiler chicks (Ross strain) were randomly divided into 7 groups with 4 replicates of 30 birds each. The treatments were NC (antibiotic-free diet), PC (basal diet with 0.05% antibiotics and 0.03% anticoccidials), PE (basal diet with 0.1% plant extract), FMP (basal diet with 0.1% fermented medicinal plants), LB (basal diet with 0.1% probiotics), PE+LB (basal diet with 0.1% plant extract and 0.1% probiotics) and FMP+LB (basal diet with 0.1% fermented medicinal plants and 0.1% probiotics). The final body weight, body weight gain and feed conversion rate in all treated groups tended to be improved or significantly improved as compared to those of NC (P<0.05). PE was significantly high in the final body weight, body weight gain of all treated groups (P<0.05). But the growth performance was significantly lower in all treated groups except PE than PC (P<0.05). No synergic effect in growth performance was found when plant extracts and Lactobacillus were mixed and fed to broilers. The ratio of albumin to globulin was significantly lower in all groups than NC (P<0.05). And the stress indicator (lymphocyte/heterophil ratio) of NC was significantly reduced than other treatments (P<0.05). No significant differences were observed on the numbers of cecal microbes and Lactobacillus. The number of cecal E. coli and Salmonella in FMP and LB were significantly reduced (P<0.05). The activity of intestinal digestive enzymes except to sucrase of treated groups significantly decreased compare to those of controls (P<0.05). These results suggest the possibility that plant extracts and Lactobacillus could be used as the alternative of antibiotic growth promoters by improving the performance of broiler chicks.