• Title/Summary/Keyword: (D/C) ratio

Search Result 2,555, Processing Time 0.033 seconds

Competition Responses between Two Different Growth Type Varieties of Barley (생육형이 다른 대맥 품종간의 경합에 관한 연구)

  • Min-Shin Cho;Deok-Hyeong Han;Sun-Mok Keun;J. D. Lee;J. C. Kang
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.7 no.1
    • /
    • pp.97-101
    • /
    • 1969
  • The experiment about the mixed sowing of two different growth type varieties of barley-Buheung and Suwon#18-has been conducted to determine the competition effect between two varieties, and its results are as follows: 1. Buheung-long stem variety-showed higher survived ratio than Suwon#18-short stem variety- and that tendency was significant under the high fertilized condition. 2. When tow varieties-Buheung and Suwon#18-were sowed together, the culm length of Buheung was shorter than the single planted Buheung and that of Suwon#18 was onger than the single planted Suwon#18, however, the panicle length showed the opposite tendency to the culm length variation. 3. The number of panicles and the number of grains did not show any differences among the treatments. 4. In case of the single sowing, Suwon#18 showed higher grain yield under the common fertilized condition but Buheung showed significantly increased grain yield under the heavy fertilized condition, however, in case of the mixed towing of two varieties, the grain yield was significantly increased in heavy fertilized plots than standard fertilization. 5. The competition power was significantly superior in Buheung to Suwon#18 and this tendency was rather definite according to the fertilizer application.

  • PDF

Creep Behavior of High-Strength Concrete with Nylon Fibers at Elevated Temperatures (고온을 받은 나일론 섬유 보강 고강도 콘크리트의 크리프 거동)

  • Kim, Young-Sun;Lee, Tae-Gyu;Kim, Woo-Jae;Kim, Gyu-Yong
    • Journal of the Korea Concrete Institute
    • /
    • v.23 no.5
    • /
    • pp.627-636
    • /
    • 2011
  • Recently, to prevent explosive spalling of high-strength concrete (HSC) members, the usage of nylon fiber instead of polypropylene fiber has increased. Past experimental studies have been conducted to examine the spalling and mechanical properties of HSC with nylon fibers when exposed to elevated temperature. However, the previous studies on HSC with nylon fibers subjected to high temperatures were performed only on the properties such as spalling, compressive strength, and elastic modulus rather than investigations on to the behaviors such as thermal strain, total strain, steady state creep, and transient creep. Therefore, in this study thermal strain, total strain, steady state creep, and transient creep of HSC mixed with nylon fibers with water to binder ratio of 0.30 to 0.15 were tested. The experimental results showed that nylon fibers did not affect the performance of HSC with nylon fibers at high temperatures. However, HSC with nylon fibers generated a larger transient creep strain than that of HSC without fibers and normal strength concrete.

Effect of Dietary Marine Microalgae (Schizochytrium) Powder on Egg Production, Blood Lipid Profiles, Egg Quality, and Fatty Acid Composition of Egg Yolk in Layers

  • Park, J.H.;Upadhaya, S.D.;Kim, I.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.28 no.3
    • /
    • pp.391-397
    • /
    • 2015
  • Two hundred and sixteen Institut de S$\acute{e}$lection Animale (ISA) brown layers (40 wks of age) were studied for 6 wks to examine the effect of microalgae powder (MAP) on egg production, egg quality, blood lipid profile, and fatty acid concentration of egg yolk. Dietary treatments were as follows: i) CON (basal diet), ii) 0.5% MAP (CON+0.5% Schizochytrium powder), and iii) 1.0% MAP (CON+1.0% Schizochytrium powder). From 44 to 46 wks, egg production was higher in 1.0% MAP treatment than in control treatment (linear, p = 0.034); however, there was no difference on the egg production from 40 to 43 wks (p>0.05). Serum triglyceride and total cholesterol were significantly reduced in the groups fed with MAP, compared to those in groups fed with control diets (Quadratic, p = 0.034 and p = 0.039, respectively). Inclusion of 0.5% MAP in the diet of layers improved egg yolk color, compared with hens fed with basal diet at 46 wks (quadratic, p = 0.044). Eggshell thickness was linearly increased in MAP-fed treatments at 46th wk (p<0.05). Concentration of yolk docosahexaenoic acid (DHA; C22:6n-3) was increased in treatment groups fed with MAP (linear, p<0.05). The n-6 fatty acids, n-6/n-3 fatty acid, and unsaturated fatty acid/saturated fatty acid were decreased in treatment groups fed with MAP (linear, p<0.05). These results suggest that MAP improved the egg production and egg quality, and may affect serum lipid metabolites in the layers. In addition, MAP increases yolk DHA levels, and deceases n-6/n-3 fatty acid ratio.

Research on Remediation of Trichloroethylene using Zero Valent Iron Bipolar Packed Bed Electrodes (영가철 충진 복극전해조를 이용한 TCE 정화기법에 관한 연구)

  • Park, Yu-Ri;Shin, Ja-Won;Park, Joo-Yang
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.32 no.1B
    • /
    • pp.85-91
    • /
    • 2012
  • Permeable Reactive Barriers (PRBs) using zero valent iron (ZVI, $Fe^0$) is a promising technology for in-situ remediation of trichloroethylene (TCE) forming dense non aqueous phase liquid (DNAPL). The objective of this study is to develop an enhanced treatment method of trichloroethylene-contaminated groundwater using ZVI packed bed with direct current (D.C.). A column experiment was performed to investigate degradation efficiency of TCE that was performed in three different combination of control (only sand), ZVI column (ZVI:sand, packing ratio 1:2(v/v)) and bipolar column (ZVI:sand=1:2(v/v) with electric current) in the test columns. As the results of this study, the degradation efficiency of TCE was improved with simultaneous application of both bipolar column compared to that used ZVI column. Because ZVI particles are isolated and individual particles act like small electrodes. In this experiment, it was indicated a basic material for application of bipolar packed bed as electro-PRBs that was effective degradation of TCE.

Influence of Fungicidal Spray on Powdery Mildew Epidemics and Major Yield-Attributing Characters of Mungbean

  • Saxen, Deep-Ratna;Moly Saxena
    • The Plant Pathology Journal
    • /
    • v.18 no.2
    • /
    • pp.68-73
    • /
    • 2002
  • The influence of fungicidal spray was assessed on powdery mildew epidemics caused by Erysiphe polygoni D.C. and on yield-attributing characters of mungbean [Vigna radiata (L.) Wilczek]. Mildew attack adversely affected the yield-attributing characters of mungbean and exhibited negative significant correlation with pod length (-0.57), pods/plant (-0.74), pod weight (-0.68), 100 seeds weight (-0.69), 100 seeds swell weight (-0.59), and seed germination (-0.71). These characters had direct or indirect effects on grain yield, which was also adversely affected due to mildew attack (-0.89). Powdery mildew was significantly retarded due to the single spray of carbendazim (0.05%) at 30-day-old crop, where the apparent rate of infection (r) was minimum at 0.0095/ unit/day and with low (11.44%) powdery mildew intensity. Other fungicides like tridemorph (0.075%) and penconazole (0.05%) were equally effective against the mildew disease where the disease intensity was less than 20% and the values of r were 0.0134 and 0.039/unit/day respectively, as compared with the control at 0.267/unit/day. Fungicide spray influenced the yield-attributing characters besides controlling the disease. Such effects were more pronounced in carbendazim (0.05%)-treated plots due to its phytotonic nature where pod length (7.59cm), pods/plant (29.75), pod weight (8.16 g), 100 grain weight (3.94 g), and swell weight of 100 seed (9.49 g) were maximum resulting to the highest yield (480 kg/ha) as compared with that of control (224 kg/ha). Spray of carbendazim also improved seed germination (74.5%). Spray of other fungicides like carbendazim with copper oxychloride in 1:1 ratio, tridemorph (0.075%), and penconazole (0.05%) was equally effective against powdery mildew of mungbean. These fungicides also exhibited positive effects on yield-attributing characters of the crop and finally increased yield. These systemic fungicides were more effective in controlling powdery mildew disease of V. radiata in the rainy season compared with wettable sulphur.

Effect of Heat Processed Ginseng on Anti-Fatigue (가공 인상의 항피로효과)

  • Shin, Y.W.;Choi, H.J.;Kim, D.H.;Park, J.H.;Kim, N.J.
    • Korean Journal of Pharmacognosy
    • /
    • v.37 no.4 s.147
    • /
    • pp.246-252
    • /
    • 2006
  • Processing of traditional herbal medicine is one of the pharmaceutical technique in oriental medicine. Most frequently used processing method in oriental medicine are roasting and steaming. In this studies, to elucidate the pharmacological transformation of traditional herbal medicine by means of processing them, Ginseng Radix (root of Panax ginseng, Araliaceae) was used as a sample. Processed ginseng radix (SGR, Sun Ginseng) was prepared by steaming of roots of white ginseng (GR) for 3 hours at $120^{\circ}C$. The biological activities of methanol extract of GR and SGR were investigated. According to DPPH radical scavenging effects, and inhibitory effects of xanthine oxidase and AAPH induced hemolysis, PGR exhibited more effective than those of GR in vitro. And, the antifatigue effect of GR and SGR were investigated using a weight-loading forced swimming test by monitoring swimming times and prolonged intensity exercise model rats by measuring blood biochemical parameters. GR and SGR were significantly prolonged swimming times in 8% body weight ratio loaded mice. Also, they had the inhibitory effects on the decrease of blood glucose levels, the elevation of serum creatinine, lactic acid and free fatty acid, and lactic dehydrogenase activities in forces swimming rats with 1% of the body weight attached to the neck for 3 hours. SGR was more excellent than GR on these effect. Also, these effects were transformed to the n-butanol fraction of methanol extract of SGR. From these results, it can be considered that SGR has antifatigue effect.

Utilization of food and Organic Wastes for Duck Feeds and Evaluation of Their Feeding Values (남은 음식물 및 유기성 폐자원을 활용한 오리사료의 제조 및 그 가치평가)

  • Chung, S.H.;Lee, S.R.;Kim, C.;Lee, D.H.;Maeng, W.J.;Kwon, Y.J.
    • Korean Journal of Poultry Science
    • /
    • v.27 no.1
    • /
    • pp.13-18
    • /
    • 2000
  • An experiment was conducted to evaluate feeding values of food and other organic wastes, and to determine their dietary effects on performance and carcass yield in ducks. A total of 156 meat type ducklings at the age of 25 days were housed in 12 pens and assigned to 4 treatments, in which the birds were fed for 21 days. One of 4 diets, commercial duck feed, raw food waste (RFW), fermented food waste(FFW) and mixture of 50% RFW and 50% FFW (R+FFW). Feed consumption was significantly higher (p<0.05) in the RFW groups. Body weight gain showed no significant differences between the control and other treatments. The feed consumption ratio was significantly higher in the RFW groups (p<0.05) than that of the other groups. Carcass yield was significantly higher in the R+FFW groups (p<0.05) than the other groups. The weight of liver per live body weight showed significant differences among the treatment groups (p<0.05). The length of intestine was significantly different from those of the treated groups(p<0.05).

  • PDF

A study on the Thermal Buckling and Postbuckling of a Laminated Composite Beam with Embedded SMA Actuators (형상기억합금 선을 삽입한 복합적층 보의 열좌굴 및 좌굴후 거동에 관한 연구)

  • Choi, S.;Lee, J.J.;Lee, D.C.
    • Composites Research
    • /
    • v.12 no.3
    • /
    • pp.55-65
    • /
    • 1999
  • In this paper, the thermal buckling and postbuckling behaviour of composite beam with embedded shape memory alloy (SMA) wires are investigated experimentally and analytically. The results of thermal buckling tests on uniformly heated, clamped, composite beam embedded with SMA wire actuators are presented and discussed in consideration of geometric imperfections, slenderness ratio of beam and embedding position of SMA wire actuators. The shape recovery force can reduce the thermal expansion of composite laminated beam, which result in increment of the critical buckling temperature and reduction of the lateral deflection of postbuckling behaviours. It is presented quantitatively on the temperature-load-deflection behaviour records how the shape recovery force affects the thermal buckling. The cross tangential method is suggested to calculate the critical buckling temperature on the temperature-deflection plot. Based on the experimental analysis, the new formula is also proposed to describe the critical buckling temperature of a laminated composite beam with embedded SMA wire actuators.

  • PDF

RADICAL IGNITION TECHNIQUE IN A CONSTANT VOLUME CHAMBER

  • Park, J.S.;Ha, J.Y.;Yeom, J.K.;Lee, J.S.;Lee, C.J.;Chung, S.S.
    • International Journal of Automotive Technology
    • /
    • v.8 no.3
    • /
    • pp.269-274
    • /
    • 2007
  • A prior fundamental study was executed using a constant volume chamber (CVC) to improve the burning characteristics of lean pre-mixture by the injection of active radicals generated in the sub-chamber of the CVC. The Radical ignition (RI) technique shows remarkable progress in the burning velocity and combustible lean limit compared with the results of the spark ignition (SI) technique. The optimum design value of the sub-chamber geometry is near $0.11cm^{-1}$ for the ratio of the total area of the holes to the sub-chamber volume $(A_h/V_s)$. In this study, based on the former experimental results, the additional works have been performed to examine the effects of the geometry change in the number $(N_h)$, the total section area $(A_h)$, and diameter $(D_h)$ of the passage holes on the combustion characteristics in the CVC. Also ambient conditions such as the initial temperature and the initial pressure of the mixture were selected as experimental parameters and the effects of residual gas at the chamber on the combustion characteristics were investigated. As a result, the correlation between the passage hole number and overall passage hole area was grasped. The effects of the initial temperature were significant, but on the other hand, those of the initial pressure were weak. A more detailed analysis on the residual gas is required in the future.

A simplified design procedure for seismic retrofit of earthquake-damaged RC frames with viscous dampers

  • Weng, D.G.;Zhang, C.;Lu, X.L.;Zeng, S.;Zhang, S.M.
    • Structural Engineering and Mechanics
    • /
    • v.44 no.5
    • /
    • pp.611-631
    • /
    • 2012
  • The passive energy dissipation technology has been proven to be reliable and robust for recent practical applications. Various dampers or energy dissipation devices have been widely used in building structures for enhancing their performances during earthquakes, windstorm and other severe loading scenarios. This paper presents a simplified seismic design procedure for retrofitting earthquake-damaged frames with viscous dampers. With the scheme of designing the main frame and the supplemental viscous dampers respectively, the seismic analysis model of damped structure with viscous dampers and braces was studied. The specific analysis process was described and approach to parameter design of energy dissipation components was also proposed. The expected damping forces for damped frame were first obtained based on storey shear forces; and then they were optimized to meet different storey drift requirements. A retrofit project of a RC frame school building damaged in the 2008 Wenchuan earthquake was introduced as a case study. This building was retrofitted by using viscous dampers designed through the simplified design procedure proposed in this paper. Based on the case study, it is concluded that this simplified design procedure can be effectively used to make seismic retrofit design of earthquake-damaged RC frames with viscous dampers, so as to achieve structural performance objectives under different earthquake risk levels.