• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.246-250
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• 1995

Konjac(Amorphophallus konjac) glucomannan dispersions were prepared from konjac flour, pretreated konjac flour and purified glucomannan. Konjac glucomannan dispersions showed non-Newtonian fluid behavior without yield stress and higher shear stress at fixed shear rate than the dispersions of gum xanthan, gum carrageenan and sodium alginate. While temperature increased, shear stress at fixed shear rate of konjac glucomannan dispersion steadily decreased. The apparent viscosity of konjac glucomannan dispersion was in its maximum at pH 7, whereas decreased on the outskirts of pH 7. The change in apparent viscosity was not found up to 1% sodium chloride addition in case of konjac glucomannan dispersion. However, the apparent viscosity of konjac glucomannan dispersion decreased up to sugar addition of 10%, afterwards increased.

• Transactions of the Korean hydrogen and new energy society
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• v.35 no.4
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• pp.451-459
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• 2024

This paper quantitatively analyzes the causes of ammonia-filled- cylinder rupture based on Tait equation and the safety guidelines, focusing on liquid expansion, internal temperature, and overfilling. When there exists a safety volume, i.e., gas-occupied volume within the ammonia cylinder, the internal pressure due to temperature rise corresponds to the vapor pressure at that temperature, with an approximate circumferential stress increase of 1.43 MPa/℃. In the absence of the safety volume, the internal pressure due to temperature rise matches the pressure of the compressed liquid ammonia at that temperature, and the resulting circumferential stress gradient in the cylinder shell is approximately 55.94 MPa/℃.

• Journal of Technology Innovation
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• v.31 no.2
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• pp.111-133
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• 2023

Innopolis start-up has become a representative model and path for commercialization of public technology. Along with the quantitative growth of innopolis start-up, the importance of innopolis start-up in national policies and institutional strategies related to public technology commercialization has also increased. However, over the past 16 years, innopolis start-up's establishment and growth have taken place in different ways at different times. This study aims to compare and analyze changes in innopolis start-up over the past 16 years, focusing on comparisons before and after 2014, when the establishment of innopolis start-up began to increase rapidly. Main findings are as follows. First, in the early stage of the quantitative expansion period, policy changes related to innopolis start-up were the main factors for the increase in innopolis start-ups. In addition, the rapid increase in the establishment of innopolis start-up after 2016 was largely influenced by changes in the start-up environment and institutional changes related to innopolis start-up. Second, the time of registration and size of the capital of innopolis start-up had a statistically significant effect on the sales for 3 years after registration. This result shows that with the rapid increase in innopolis start-ups, the need to build a customized support system for innopolis start-ups by size or growth stage has increased.

• Proceedings of the Technology Innovation Conference
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• 2005.08a
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• pp.168-188
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• 2005

본 연구는 R&D가 경영성과에 미치는 영향에 대해 전기$\cdot$전자산업에 속한 중소기업과 벤처기업을 대상으로, 패널 데이터 (2001$\~$2003년)를 이용하여 실증분석하고, 중소기업과 벤처기업을 비교분석하였다. 실증분석 모델은 기업의 총매출액을 종속변수로 하고, R&D 투자액, 연구원 수, 자본금 총액, 종업원 수, 연구원 수를 제외한 종업원 수를 독립변수로 한 1차 선형함수를 설정하였다. 실증분석모델로는 패널분석 (임의효과모델, Random Effect Model)을 이용하였다. 실증분석 결과 중소기업과 벤처기업의 공통점은 첫째, R&D 인력과 그것을 제외한 종업원수가 경영성과에 대한 영향이 긍정적이라는 점 둘째, R&D 투자액 및 자본금이 기업의 경영성과에 긍정적인 영향을 주고 있다는 점을 들 수 있다. 실증분석 곁과의 차이점은 첫째, 중소기업의 경우 연구소 설립 연수와 기업 설립 연수가 기업의 경영성과와 무상관으로 나타났으나, 벤처기업의 경우 추정결과 1을 제외하면 모두 긍정적이고 유효했으며 둘째, 중소기업의 경우 자산효과와 자본금 효과가 긍정적이고 유효한 것으로 나타났으나, 벤처기업은 자산효과가 유효한 부정으로 나타났다. 따라서 기업은 인적자원의 확보, 육성, 활용 등의 전락에 의해 기업 경영성과가 크게 달라질 수 있고, 중소기업이나 벤처기업의 경우 자산의 팽창보다는 시장 경쟁력 향상을 위한 R&D투자에 좀 더 힘써야 할 것이다.

• Korean Journal of Animal Reproduction
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• v.23 no.4
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• pp.281-291
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• 1999

The objective of this study was to optimize the freezing/thawing method of in vitro produced Hanwoo blastocysts. Day 7 blastocysts after IVF were vitrified using EFS40 (40% ethylene glycol, 18% ficoll, 0.3 M sucrose and 10% FBS added m-DPBS) as a freezing solution and electron microscope (EM) grid (V-G) or straw (V-S) as an embryo container. In both method, freezing/thawing were treated by 2-step, treatment time was required in V-G method and V-S method, for 2 min / 3 min and 3.5 min / 10 min, respectively. Embryo survival was assessed as re-expanded and hatched rates at 24 h and 48 h after warming, respectively. The results obtained in these experiments were summarized as follows: when the effect of exposure in vitrification solution and chilling injury from freezing procedure on in vitro produced expanded blastocysts were examined, at 24 h after warming, embryo survival in exposure group (100.0%) was not different compared to that in control group (100.0%), although those results were significantly different with two vitrified groups (V-G: 87.8, V-S: 77.8%) (P＜0.001). However, at 48 h after warming, hatched rates of V-G group (67.8%) were significantly higher than those of V-S group (53.3%) (P＜0.05). In addition, this hatched rate in V-G group was not different with that in exposure group (73.3%). When the effects of embryo developmental stage (early, expanded and early hatching blastocysts) and embryo container (EM grid and straw) to the in vitro survival of vitrified-warmed day 7 Hanwoo blastocysts were simultaneously examined, fast developed embryos were indicated the better resistance to freezing than delayed developed one, irrespective of embryo containers (early; 57.1 ＆ 24.4%, expanded; 84.7 ＆ 60.6%, early hatching; 91.7 ＆ 80.0%) (P＜0.001). Especially, in expanded and early hatching blastocysts, embryo survival of V-G group (67.8, 95.0%) was significantly higher than those of V-S group (53.0, 65.0%) at 48 h post warming, respectively (P＜0.05, P＜0.001). Therefore, this study indicates that Hanwoo blastocysts can be cryopreserved more simple, efficient and successful by vitrification method using EM grid.

• Food Science and Preservation
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• v.17 no.4
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• pp.487-493
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• 2010

This study was conducted to evaluate quality characteristics of white breads with Acanthopanax senticosus extract(ASE) (0, 25, 50, 75 and 100%). Addition of ASE significantly decreased L-value, and increased a and b-values. Compared with the control bread, specific volume of bread added with ASE was increased. The cohesiveness, springiness and gumminess of the breads added with ASE were higher than those of the control group. Also, a sensory evaluation was carried out in terms of acceptability(color, flavor, taste, texture and overall acceptability). Taken together, the 50% treatment ranked the highest evaluation values, as compared to other treaments. Accordingly, to improve the quality of bread, it is recommendable to add ASE to the 50% level in substitution for water in making a loaf of bread. After all, this study was to confirm the possibility of ASE's utilization as natural materials containing the functional substance.

• Journal of Life Science
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• v.23 no.2
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• pp.222-227
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• 2013

An effective leavening yeast was isolated from raisin broth. The isolate was identified as Saccharomyces cerevisiae by comparing the homology of 18S rDNA ITS sequences and named as S. cerevisiae MF10003. S. cerevisiae MF10003 showed a 1.9-fold and 3.1-fold increase in $CO_2$ production and leavening ability, respectively, compared with the wild yeast S. ellipsoideus KCTC7243, and the dough had a rich and volatile flavor. When glucose, sucrose, fructose, and maltose were added to the culture broth as a carbon and energy source, $CO_2$ was produced in 4 hr.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1288-1293
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• 2012

Yacon (Smallanthus sonchifolius) contains high amounts of fructooligosaccharides and has been known to promote health of the intestinal tract and to have anti-oxidative and anti-cancer activities. Yacon concentrates were added to make five different pan breads, each with the addition 0% (YE 0), 25% (YE 25), 50% (YE 50), 75% (YE 75), and 100% (YE 100) of yacon concentrates instead of sugar. The higher the yacon concentration in the dough, the more time was needed for the dough to rise. Higher yacon concentration also affected the color of the bread by lowering the L-value and raising the a and b values. The hardness and chewiness of the bread significantly decreased with increasing yacon concentration, while cohesiveness increased. In the bread sensory evaluation, the intensity of crust color, crumb color, yacon flavor, sweetness, yacon taste, moistness, and residual mouth feel were increased with increasing yacon concentrates, while the uniformity of crumb pores slightly decreased. The consumer acceptance of taste, flavor, texture, and overall acceptance were increased with increasing yacon concentrations. As a conclusion, the substitution of yacon concentrates for sugar improved bread quality and increased consumer acceptance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.971-978
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• 2017

Danggui leaf (Angelica acutiloba Kitagawa) has numerous dietary fiber and healthy functional properties such as anti-inflammatory activity. However, it is usually discarded after its roots are harvested. For wide application of danggui leaf, squeezed danggui leaf juice was used for making pan bread. Treatments included imported wheat flour (IMWF) and domestic wheat flour (DOWF) as a control, 1% soluble solid contents of squeezed danggui leaf juice instead of wheat flour (1% SDLJ), 2% SDLJ, 3% SDLJ, and 4% SDLJ. In the fermentation expansion, dough volume was not significantly different between DOWF and 1% SDLJ, whereas it decreased according to increased amount of squeezed danggui leaf juice. Regarding physical properties, springiness and cohesiveness decreased according to increased amount of squeezed danggui leaf juice and longer storage period. Gumminess, brittleness, and hardness increased according to increased amount of squeezed danggui leaf juice, although these were not statistically different among IMWF, DOWF, and 1% SDLJ after making pan bread. Principal component analysis (PCA) was performed to assess the correlation between storage period and physical properties. In the PCA, variance proportion of principal component (PC) 1 was 0.87 while that of PC 2 was 0.10. Further, 1% SDLJ showed similar results as DOWF and INWF after making pan bread and after 3 days of storage. In conclusion, use of 1% SDLJ is desirable for making squeezed danggui leaf juice.

• Korean Journal of Food Science and Technology
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• v.49 no.2
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• pp.168-172
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• 2017

In this study, the fermentative characteristics of rye sourdough fermented with Omija extract were investigated. The pH and total titratable acidity, numbers of yeast and lactic acid bacteria, and expansion rate were measured. While the pH of Omija rye sourdough decreased from 5.60 to 3.86, the total titratable acidity significantly increased from 2.39 to 8.50 with fermentation time (p<0.05). The numbers of yeast and lactic acid bacteria significantly increased for 18 h of fermentation period (p<0.05). The expansion rate of Omija rye sourdough showed a maximum of 183%, more than 47% more than the highest value of rye sourdough (129%). These results suggest that the application of Omija extract for making sourdough could be a good way to decrease the sanitary risk especially for early stage of sourdough fermentation. In addition, Omija rye sourdough could contribute to improvement of baking quality such as volume increase and flavor improvement of rye bread.