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Changes in Quality Characteristics of Jeungpyun containing different Levels of Malt Extract during Storage (엿기름 추출액의 첨가량에 따른 증편의 저장 중 품질 특성 변화)

  • Jung, Kyoung-Wan;Kim, Yoo-Kyung;Lee, Gui-Chu
    • Journal of the Korean Society of Food Culture
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    • v.26 no.5
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    • pp.521-529
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    • 2011
  • This study evaluated the effects of different levels of malt extract on the hardness, moisture, water soluble starch (WSS) contents, and in vitro starch digestibility (IVSD) of Jeungpyun during storage at room temperature ($25{\pm}1^{\circ}C$) and refrigeration temperature ($4{\pm}1^{\circ}C$). Resistant starch (RS) and soluble starch (non-RS) contents were also evaluated. During storage at both temperatures, hardness increased in Jeungpyuns with the malt extract-added Jeungpyun groups (malt-added Jeungpyuns) exhibiting lower hardness than the control. The rate of retrogradation was faster upon storage at refrigeration temperature. Moisture and WSS contents as well as IVSD of Jeungpyuns decreased, whereas these levels were higher in malt-added Jeungpyuns compared to control. Storage increased RS contents in Jeungpyuns stored for up to 4 days, particularly at $4^{\circ}C$, whereas there was a decrease in RS content after 7 days of storage. However, RS content was lower in malt-added Jeungpyuns compared to control. Soluble starch (SS) contents of Jeungpyuns decreased. However, SS content was higher in malt-added Jeungpyuns than that of control. The reduced hardness and RS content as well as the rate of increase in other parameters of malt-added Jeungpyuns were dependent on the concentration of malt extract. These results reveal that addition of malt extract delayed retrogradation of Jeungpyun, whereas retrogradation possibly increased the content of RS during storage at both temperatures, however, that of RS decreased with increasing level of malt extract, suggesting that the level of malt extract as well as the storage conditions are important for obtaining acceptable texture and retaining the RS content of Jeungpyun, which is known to possess physiological activity.

Dissolution Profiles of Solid Dispersions Containing Poorly Water-Soluble Drugs and Solubilizing Compositions (가용화 조성물과 난용성 약물군을 함유하는 고체분산체의 용출양상)

  • Kim, Tae-Wan;Choi, Choon-Young;Cao, Qing-Ri;Kwon, Kyoung-Ae;Lee, Beom-Jin
    • Journal of Pharmaceutical Investigation
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    • v.32 no.3
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    • pp.191-197
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    • 2002
  • Polymer based physical mixtures or solid dispersions containing solubilizing compositions[OA, tween80 and SLS] were prepared using a spray-dryer. Lovastatin(LOS), simvastatin(SIMS), aceclofenac(AFC) and cisapride(CSP) were selected as poorly water-soluble drugs. Dextrin, poly(vinylalcohol) (PVA), poly(vinylpyrrolidone)(PVP) and polyethylene glycol(PEG) were chosen as solubilizing carriers for solid dispersions. The solid dispersions containing solubilizing compositions without drug were prepared without using organic solvents or tedious changes of formulation compositions. This system could be used to quickly screen the dissolution profiles of poorly water-soluble drugs by simply mixing with drugs thereafter. In case of solid dispersion containing drug, organic solvent systems could be used to solubilize model drugs. The dissolution rates of the drugs were higher when mixed with drug and solid dispersions containing solubilizing compositions. However, solid dispersions of LOS, AFC, and CSP simultaneously containing drug and solubilizing compositions in organic solvent systems were more useful than physical mixtures of drug and solid dispersions without drug except SIMS. Based on solubilizing capability of polymer based physical mixtures in gelatin hard capsules, optimal solid dispersion system of poorly water-soluble drugs could be formulated. However, it should be noted that dissolution rate of poorly water-soluble drugs were highly dependent on drug properties, solubilizing compositions and polymeric carriers.

A CFD Study of the Supersonic Ejector-Pump Flows (초음속 이젝터 펌프 유동에 관한 수치해석)

  • 이영기;김희동;서태원
    • Journal of the Korean Society of Propulsion Engineers
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    • v.3 no.4
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    • pp.58-66
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    • 1999
  • The flow characteristics of supersonic ejectors is often subject to compressibility, unsteadiness and shock wave systems. The numerical works carried out thus far have been of one-dimensional analyses or some Computational Fluid Dynamics(CFD) which has been applied to only a very simplified configuration. For the design of effective ejector-pump systems the effects of secondary mass flow on the supersonic ejector flow should be fully understood. In the present work the supersonic ejector-pump flows with a secondary mass flow were simulated using CFD. A fully implicit finite volume scheme was applied to axisymmetric compressible Navier-Stokes equations. The standard two-equation turbulence model was employed to predict turbulent stresses. The results obtained showed that the flow characteristics of constant area mixing tube types were nearly independent of the secondary flow rate, but the flow fields of ejector system with the second-throat were strongly dependent on the secondary flow rate due to the effect of the back pressure near the primary nozzle exit.

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Effects of Dietary Cellulose Levels on Growth, Nitrogen Utilization, Retention Time of Diets in Digestive Tract and Caecal Microflora of Chickens

  • Cao, B.H.;Zhang, X.P.;Guo, Y.M.;Karasawa, Y.;Kumao, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.6
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    • pp.863-866
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    • 2003
  • This study was conducted to examine the effects of dietary cellulose levels on growth, nitrogen utilization, the retention time of diets in the digestive tract, and caecal microflora of 2-month-old Single Comb White Leghorn male chickens fed 3 purified diets that contained 0, 3.5% and 10% cellulose in equal amount of nutrients for 7 days. Body weight gain and nitrogen utilization were significantly higher (p<0.05), while total microflora counts in the caecal contents and retention time of the diet in the digestive tract were significantly lower (p<0.05) in the group fed 3.5% dietary cellulose compared with the group fed 10% dietary cellulose. Body weight gain, nitrogen utilization and retention time of the diet in the digestive tract decreased significantly while the total microflora count in the caecal contents increased significantly in the group fed 10% dietary cellulose compared to the group fed 0% dietary cellulose (p<0.05). Chickens fed 10% dietary cellulose had significantly increased counts of uric acid-degradative bacteria such as Peptococcaceae and Eubacterium, including Peptostreptococcus (p<0.05). The results suggest that cellulose in purified diets is an effective ingredient and the effects on growth, nitrogen utilization, caecal microflora counts and diet retention time in the digestive tract are dependent on the inclusion rate. Positive or negative effects of dietary cellulose are displayed by growth, nitrogen utilization, caecal microflora counts and retention time of the diet in the digestive tract. Positive effects were displayed when the inclusion rate is 3.5% and negative effects were displayed when that is greater than 3.5% of the diet, and the phenomenon is without reference to the age of the chickens.

Conjugated Linoleic Acid as a Key Regulator of Performance, Lipid Metabolism, Development, Stress and Immune Functions, and Gene Expression in Chickens

  • Choi, Yang-Ho
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.3
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    • pp.448-458
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    • 2009
  • It has been well documented from animal and human studies that conjugated linoleic acid (CLA) has numerous beneficial effects on health. In chickens, CLA exerts many effects on performance ranging from egg quality and yolk lipids to meat quality. Although there are several CLA isomers available, not all CLA isomers have the same incorporation rates into egg yolk: cis-9,trans-11 and trans-10,cis-12 CLA isomers are more favorably deposited into egg yolk than other isomers investigated, but of the two isomers, the former has a higher incorporation rate than the latter. CLA alters the amounts and profiles of lipids in plasma, muscles and liver. Furthermore, increased liver weight was reported in chickens fed dietary CLA. As observed in egg yolk, marked reduction in intramuscular lipids as well as increased protein content was observed in different studies, leading to elevation in protein-to-fat ratio. Inconsistency exists for parameters such as body weight gain, feed intake, feed conversion ratio, egg production rate and mortality, depending upon experimental conditions. One setback is that hard-cooked yolks from CLA-consuming hens have higher firmness as refrigeration time and CLA are increased, perhaps owing to alterations in physico-chemistry of yolk. Another is that CLA can be detrimental to hatchability when provided to breeders: eggs from these breeders have impaired development in embryonic and neonatal stages, and have increased and decreased amounts of saturated fatty acids and monounsaturated fatty acids (MUFAs), respectively. Thus, both problems can be fully resolved if dietary sources rich in MUFAs are provided together with CLA. Emerging evidence suggests that CLA exerts a critical impact on stress and immune functions as it can completely nullify some of the adverse effects produced by immune challenges and reduce mortality in a dose-dependent manner. Finally, CLA is a key regulator of genes that may be responsible for lipid metabolism in chickens. CLA down-regulates both expression of the gene encoding stearoyl-CoA desaturase-1 and its protein activity in the chicken liver while up-regulating mRNA of sterol regulatory element-binding protein-l.

High Temperature Compressive Properties of Tungsten Activated Sintered Pare Prepared by 0.4 wt.% Ni-doped Tungsten Powder Compacts (0.4 wt% Ni을 첨가한 W 활성소결체의 고온압축 특성 연구)

  • 이승익;김순욱;박영삼;문인형
    • Journal of Powder Materials
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    • v.9 no.5
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    • pp.307-314
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    • 2002
  • The high temperature deformation behavior of the activated sintered W powder compacts was investigated. The W compact showed the relative density of 94% with the average W grain size of $23\mutextrm{m}$ by activated sintering at $1400^{\circ}C$ for 1 hour. Compression tests were carried out in the temperature range of $900-1100^{\circ}C$ at the strain rate range of $10^{0}$/sec - $10^{-3}$/sec. True stress-strain curve and microstructure exhibited the grain boundary brittleness which was dependent on the compression test temperature. The activated sintered W compact showed that the maximum stress as well as the strain at the maximum stress was abruptly decreased as the test temperature increase from $900^{\circ}C$ to 1000 and $1100^{\circ}C$ regardless of the strain rate. The discrepancy of the microstructure in the specimen center was obviously observed with the increase of the test temperature. After compression test at $900^{\circ}C$ the W grain was severely deformed normally against the compression axis. However, after compression test at $1000^{\circ}C$ and $1100^{\circ}C$ the W grain was not deformed, but the microcrack was formed in the W grain boundary. The Ni-rich second phase segregated along the W grain boundary could be partly unstable over $900^{\circ}C$ and affect the poor mechanical property of the activated sintered W compact.

The Effect of E-Business on Firm's Growth and Profitability in the Distribution Industry (e-비즈니스의 유통기업 성장성 및 수익성 기여 효과분석)

  • Baek, Chul-Woo
    • Journal of Distribution Science
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    • v.15 no.1
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    • pp.123-130
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    • 2017
  • Purpose - This research aims to examine the effect of e-business adoption on firm's growth and profitability in the distribution industry. The value added from the distribution industry acts as the cost of other industries. As the distribution industry develops, its stage becomes shorter and the distribution margin becomes smaller. Therefore, e-business is expected to have a different effect on the distribution industry than other industries. Research design, data and methodology - The previous research generally used e-business adoption as an independent variable and firm's performance as a dependent variable. This study elaborated the model using a dynamic panel model that includes the performance variable of the previous year as an independent variable. By employing system GMM (Generalized Method of Moments), the endogeneity problem in the dynamic panel model can be solved. For the analysis, I extracted the distribution companies as the raw data in the National Statistical Office's Business Activity Survey over the period 2006 to 2012. Results - The growth rate of firms adopting e-business was 0.299%p higher than that of the non-adopter. However, only ERP (Enterprise Resource Planning), KMS (Knowledge Management System) and SCM (Supply Chain Management) contributed positively to the growth rate. In the case of profitability, it was 0.04%p higher than the distribution companies that did not adopt e-business. ERP and LMS (Learning Management System) improve profitability, while SCM reduces profitability. Consequently, while ERP improves both growth and profitability, SCM improves growth but reduces profitability. In addition, KMS improves firm's growth only, and LMS does only profitability, showing that each e-business has a differentiated effect. Conclusions - Since the distribution industry has different characteristics from manufacturing and other service industries, the introduction of e-business may not guarantee the growth and profitability of distribution companies. Careful introduction considering the characteristics of the distribution industry is required. In particular, it is necessary to select an e-business meeting the characteristics and needs of a distribution company, and thereafter, it is required for the company's own efforts to internalize it within the system.

Visitor Behavior and Satisfaction in Suburban Recreational Forests - Focused on the suburbs of Seoul - (도시근교형 자연휴양림 이용 행태와 만족도 분석 - 서울 근교를 중심으로 -)

  • 서주환;최현상;전형석
    • Journal of the Korean Institute of Landscape Architecture
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    • v.30 no.6
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    • pp.57-65
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    • 2003
  • This study researches attributes , behaviors , satisfaction factors and degrees of curiosity of visitors to recreational forests in the suburbs of a large city. It aims to present suggestions for urban forest development and management policy by offering basic data which help to plan, design and manage recreational forests to increase the quality of these environments. The results are as follows First, in attribute, the visiting rate of males is higher than that of females, and the main users are in their thirties and forties. Sixty percent of visitors graduated from university and their rate of employment is evenly distributed. 95 percent of visitors are residents of the metropolitan area. In terms of behavior, major visitors are family units visiting during summer seasons and for overnight stays. 75% are re-visitors. 85% of visitors came to escape the city with families and friends, keep in good health and experience nature. Second, to extract the factors affecting visitor satisfaction in recreational forests, the natural environment, facilities, and management/use systems were identified as independent variables, while subordinate satisfactions were dependent variables. so regression analysis was used. Thus, the variables affecting the natural environment are quality of water, stream use, biodiversity, fresh air and landscape factors. The variables affecting facilities are puking, convenience, play facilities, sanitary arrangement and camping. Most important among the variables affecting management/use systems are educational facilities and access condition. On the basis of generalizing the study in the existing individual site, we must verify the visiting characteristics in recreational forests in the suburbs of a large city. Since development of recreational forests is understood as a sequence considering a site and a given condition, and since management and improvement must unfold according to these characteristics, a strategy is needed to reveal visitors' opinions about the site. Depending on the facilities and service, satisfaction of recreational forests is generally influenced by social and economic qualities. Also, this study can look into the effect according to use pattern motive and season. As suburban recreational forests have many overnight-users and younger men, programs suitable for these groups are needed. On the basis of variables affecting satisfaction according to natural environment, facilities, and use system, policies which can manage the natural environment and introduce educational programs are needed.

Cardiac Response to Head-Out Water Immersion in Man

  • Choi, Jang-Kyu;Park, Won-Kun
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.3
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    • pp.253-261
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    • 2000
  • Head-out water immersion induces marked increase in the cardiac stroke volume. The present study was undertaken to characterize the stroke volume change by analyzing the aortic blood flow and left ventricular systolic time intervals. Ten men rested on a siting position in the air and in the water at $34.5^{circ}C$ for 30 min each. Their stroke volume, heart rate, ventricular systolic time intervals, and aortic blood flow indices were assessed by impedance cardiography. During immersion, the stroke volume increased 56%, with a slight (4%) decrease in heart rate, thus cardiac output increased ${\sim}50%.$ The slight increase in R-R interval was due to an equivalent increase in the systolic and diastolic time intervals. The ventricular ejection time was 20% increased, and this was mainly due to a decrease in pre-ejection period (28%). The mean arterial pressure increased 5 mmHg, indicating that the cardiac afterload was slightly elevated by immersion. The left ventricular end-diastolic volume index increased 24%, indicating that the cardiac preload was markedly elevated during immersion. The mean velocity and the indices of peak velocity and peak acceleration of aortic blood flow were all increased by ${\sim}30%,$ indicating that the left ventricular contractile force was enhanced by immersion. These results suggest that the increase in stroke volume during immersion is characterized by an increase in ventricular ejection time and aortic blood flow velocity, which may be primarily attributed to the increased cardiac preload and the muscle length-dependent increase in myocardial contractile force.

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Kinetics of 2, 4, 6-Trinitrotoluene reduction by zero valent iron (금속 철을 이용한 TNT 환원시의 동역학 산정)

  • 배범한
    • Journal of Korea Soil Environment Society
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    • v.4 no.1
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    • pp.97-108
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    • 1999
  • Reduction 2, 4, 6-trinitrotoluene by zero valent iron was studied in a batch reactor under anoxic conditions. Results showed that the removal of trinitrotoluene (TNT)followed a pseudo-first order reaction and the rate was linearly dependent on the available reactive surfau area of the zero valent iron surface area, resulting a rate constant of 0.0981min$^{1}m$$^{-2}m$. High concentrations of the final product, presumably triaminotoluene which needs to be treated by other means, accumulated in the solution. However , little amount of TAT was extracted from the metal surface by using acetonitrile or phosphate buffered water (pH 7.0). Other common major intermediate in biological TNT degradation, a group of aminodinitrotoluenes, was not detected in the solution. Therefore, it is postulated that the reduction of nitro group by $Fe^0$ occurs simultaneously in all three positions and a TNT reduction model by zero valent iron was suggested.

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