• Title/Summary/Keyword: Composition

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Effect of gas composition on dispersion characteristics of blowout gas on offshore platform

  • Yang, Dongdong;Chen, Guoming;Shi, Jihao;Li, Xinhong
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.11 no.2
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    • pp.914-922
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    • 2019
  • Gas composition has a significant impact on the dispersion behavior and accumulation characteristics of blowout gas. However, few public studies has investigated the corresponding effect of gas composition. Therefore, this study firstly builds the FLACS-based numerical model about an offshore drilling platform. Then several scenarios by varying the composition of blowout gas are simulated while the scenario with the composition of "Deepwater Horizon" accident is regarded as the benchmark. Furthermore, the effects of the gas composition on the flammable cloud volume, the influenced area of flammable cloud, the influenced area of hydrogen sulfide and the critical time of the hydrogen sulfide spreading to the living area are analyzed. The results demonstrate that gas composition is a driving factor for dispersion characteristics of blowout gas. All the results can give support to reduce the risk of the similar accidents incurred by real blowouts.

Capacity Modulation of a Heat Pump System by Changing the Composition of Refrigerant Mixtures (혼합냉매의 성분비 조절을 통한 열펌프의 용량조절)

  • 김민성;김민수;김용찬
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.3
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    • pp.258-266
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    • 2000
  • Experimental investigation and cycle simulation of a capacity modulation of a heat pump system using a hydrofluorocarbon (HFC) refrigerant mixture, R32/134a as an alternative to R22, have been done. In the cycle simulation, the refrigeration system was operated by assigning the temperatures of the external heat transfer fluids with the heat exchangers generalized by an average effective temperature difference. Heating capacity, cooling capacity, and coefficient of performance (COP) of the system were investigated at several operating conditions. Experimental apparatus which had a refrigeration part and a composition changing part was built, and the performance of the heat pump system filled with R32/134a mixture was investigated. A gas-liquid separator was used in the experiment to change the composition by collecting the vapor and the liquid Phase separately, The mass fraction of the charged refrigerant in the heat pump system was 40/60 and 70/30 by weight percentage. The composition of the refrigerant with initial composition of 40/60 varied from 29/71 to 41/59 in the refrigeration cycle. For the refrigerant with initial composition of 70/30, the composition varied from 65/35 to 75/25.

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Monitoring the Current Nutrition Labeling Practice on the Packaging of Processed Foods (시판 가공식품의 영양표시 실태 모니터링에 관한 연구)

  • Kim, Ok-Sun;Oh, Se-In;Jang, Young-Ai
    • Korean journal of food and cookery science
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    • v.21 no.5
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    • pp.616-628
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    • 2005
  • The purpose of this study was to monitor the current nutrition labeling practice on the packaging of the processed foods providing consumers with reliable nutrition information, which has been considered as a useful aid for food selection and a potent educational tool for nutrition in a daily life. The 2,214 processed foods purchased at the a wholesale market in July, 2003, were divided by food categories issued from the 2003 food codes and assessed in the terms of the nutrition composition labeling and nutrition claims. Nutrition composition labeling was found on 533 out of the 2,214 processed foods items. The findings of this study were as follows : Milk and dairy products had 66.4% of nutrition composition labeling, which was the largest percentage among the food categories. Tables format (71.3%) is the most widely used type of nutrition labeling. The title of nutrition composition labeling used the most widely was nutrition composition (71.3%). Nutrition composition included many different ways of expression, such as a table of nutrition composition, and indication of nutrition composition, etc. The expression unit of the nutrition composition labeling was use per 100g or 100mL (40.5%). The processed foods with nutrition claims were 18.0% (399 items). Nutrition claims were divided into two categories: nutrient content claims and nutrient comparative claims. The most frequently used nutrient content claims were contained (43.9%) and more or plus in the nutrient comparative claims (16.0%). Ca was the most popular item as a nutrition claim nutrient (33.6%).

Application of X-ray Computer Tomography (CT) in Cattle Production

  • Hollo, G.;Szucs, E.;Tozser, J.;Hollo, I.;Repa, I.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.12
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    • pp.1901-1908
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    • 2007
  • The aim of this series of experiments was to examine the opportunity for application of X-ray computer tomography (CT) in cattle production. Firstly, tissue composition of M. longissimus dorsi (LD) cuts between the $11-13^{th}$ ribs (in Exp 1. between the $9-11^{th}$ ribs), was determined by CT and correlated with tissue composition of intact half carcasses prior to dissection and tissue separation. Altogether, 207 animals of different breeds and genders were used in the study. In Exp. 2 and 3, samples were taken from LD cuts, dissected and chemical composition of muscle homogenates was analysed by conventional procedures. Correlation coefficients were calculated among slaughter records, tissues in whole carcasses and tissue composition of rib samples. Results indicated that tissue composition of rib samples determined by CT closely correlated with tissue composition results by dissection of whole carcasses. The findings revealed that figures obtained by CT correlate well with the dissection results of entire carcasses (meat, bone, fat). Close three-way coefficients of correlation (r = 0.80-0.97) were calculated among rib eye area, volume of cut, pixel-sum of adipose tissue determined by CT and intramuscular fat or adipose tissue in entire carcasses. Estimation of tissue composition of carcasses using equations including only CT-data as independent variables proved to be less reliable in prediction of lean meat and bone in carcass ($R^2 = 0.51-0.86$) than for fat (($R^2 = 0.83-0.89$). However, when cold half carcass weight was also included in the equation, the coefficient of determination exceeded $R^2 = 0.90$. In Exp. 3 tissue composition of rib samples by CT were compared to the results of EUROP carcass classification. Findings revealed that CT analysis has higher predictive value in estimation of actual tissue composition of cattle carcasses than EUROP carcass classification.

Effects of Korean Herbal Bathing Extracts Composition on Th2 Cytokine Production in MC/9 Mast Cells (한방 입욕제 조성물이 MC/9 mast cell에서의 Th2 cytokine 발현에 미치는 영향)

  • Jang, Moon-Hee;Choi, Jae-Song;Choi, Ae-Ryun;Ahn, Taek-Won
    • Journal of Sasang Constitutional Medicine
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    • v.24 no.3
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    • pp.80-92
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    • 2012
  • Objectives The purpose of this study is to investigate the effects of korean herbal bathing extracts composition 1 and composition 2 on Th2 cytokine production in MC/9 mast cells. Methods The effects of composition 1, 2 was analyzed by ELISA and Real-time PCR in MC/9 mast cells. Levels of IL-5, IL-13 were measured using enzyme-linked immunosorbent assays(ELISA). mRNA levels of IL-4, IL-5, IL-6, IL-13 were analyzed with Real-time PCR. Results Composition 1, 2 inhibited the IL-5, IL-13 production significantly(p<.001) in comparison to PI-control group at concentration of 100 ${\mu}g/mL$, 200 ${\mu}g/mL$. Composition 1, 2 inhibited the IL-4, IL-5, IL-13 mRNA expression significantly in comparison to PI-control group at concentration of 100 ${\mu}g/mL$, 200 ${\mu}g/mL$. Composition 1 inhibited the IL-6 mRNA expression significantly in comparison to PI-control group at concentration of 200 ${\mu}g/ml$. Composition 2 inhibited the IL-6 mRNA expression significantly in comparison to PI-control group at concentration of 100 ${\mu}g/mL$, 200 ${\mu}g/mL$. Conclusions These results indicate that composition 1, 2 has the effect of decreasing the Th2 cytokine production in the MC/9 mast cell.

A Study on the Effect of Gas Composition at Gas Supply Point on the Pressures in Gas Pipe Networks (가스 배관망에서 인입가스의 조성이 배관망 내 압력에 미치는 영향에 관한 연구)

  • Chang, Seung-Yong
    • Journal of the Korean Institute of Gas
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    • v.11 no.2 s.35
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    • pp.1-4
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    • 2007
  • Natural gas has different gas composition according to imported gas region, and the difference of gas composition affects pressure loss value occurred in pipe networks, Therefore, using real gas composition instead of averaged gas composition can obtain more reliable results for pipe network analysis. In this study, the effect of real gas composition at gas supply points on the demand pressure has been analyzed. To compare the results, the calculated pressure values for averaged gas composition at all the supply points have been used. From the results, we found that the effect of real gas composition consideration on demand pressure was considerable, and the real gas composition has to be considered for reliable pipe network analysis in gas industry.

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Effects of Sm:Ba:Cu Composition Ratio on the Superconducting Properties of SmBCO Coated Conductor Prepared by using a Composition Gradient Method (SmBCO 초전도 선재 특성에 대한 Sm:Ba:Cu 조성비의 영향)

  • Kim, H.S.;Oh, S.S.;Jang, S.H.;Min, C.H.;Ha, H.S.;Ha, D.W.;Ko, R.K.;Youm, D.J.;Moon, S.H.;Chung, K.C.
    • Progress in Superconductivity
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    • v.13 no.1
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    • pp.7-11
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    • 2011
  • The effects of Sm:Ba:Cu composition ratio in SmBCO coated conductor on their superconducting properties were investigated. The SmBCO coated conductors were fabricated by reactive co-evaporation method using EDDC(Evaporation using Drum in Dual Chamber) system. In this system, we could obtain various samples with different composition ratios in a batch by the technique providing composition gradient at deposition zone. From the specimens prepared by EDDC system, we found that composition ratio is uniform parallel to the drum axis, but gradient along the circumferential direction of the drum. We installed a shield having parallelogram open area between the deposition chamber and the evaporation chamber in EDDC system, and attached a 30 cm long template, which is parallel to drum axis, onto the drum surface. In this configuration, we could obtain SmBCO coated conductors having a gradient composition along the length of template. We measured the composition ratios and surface morphologies with periodic interval by SEM and EDAX, and confirmed the profile of composition ratio. We also measured critical current using non-contact Hall probe critical current measurement system and thereby could plot composition ratio vs. critical current. The maximum critical current was obtained, and the surface morphology with the shape of roof tile was observed at the corresponding composition ratio of Sm:Ba:Cu = 1.01:1.99:4.87. It was also found that composition ratio had an effect on not only critical current but also surface morphology.

Effect of Chemical Composition on the Latent Hydraulic Activity of Blast Furnace Slag (고로슬래그의 잠재수경성에 미치는 화학조성의 영향)

  • 장복기;임용무
    • Journal of the Korean Ceramic Society
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    • v.37 no.5
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    • pp.453-458
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    • 2000
  • Glasses showing the composition of blast furnace slag were made in the laboratory, and the effect of the chemical composition on the latent hydraulic activity of the slags was examined. The latent hydraulicity was greatly influenced by the composition change, the optimal characteristic of the hydraulicity was achieved at the slag composition of 47CaO:20Al2O3:33SiO2. The content of CaO and Al2O3 were not equivalent to the hydraulic activity of the slags as the b-formula (KS L 5210) indicates. Good latent hydraulicity was shown when Al2O3 was richly contained at the high (CaO+Al2O3):SiO ratio, while the more the MgO content was, the more negative the result turned out.

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A study on the link composition design of a double link type level luffing jib crane (II) (이중 링크 형식 수평 인입 집 크레인의 링크 구성 설계에 관한 연구(II))

  • Hur, C.W.;Choi, M.S.;Moon, D.H.
    • Journal of Power System Engineering
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    • v.15 no.1
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    • pp.57-63
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    • 2011
  • It is very important to determine link composition of a crane in the basic design of the crane. There are many parameters in the design for the link composition of a double link type level luffing jib crane. We analyze the variation of link composition according to the variation of these parameters which are the angle of fixed link, the angle between the fixed link and backstay when the position of the crane is the maximum working radius, the ratio of fly jib length between two moving hinges to the total length of fly jib, the length of backstay, and the slewing radius. In this paper, we describe the application of the previous analysis program of the link composition design for a double link type level luffing jib crane.