• Journal of Animal Science and Technology
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• v.58 no.1
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• pp.4.1-4.7
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• 2016

Background: This study was conducted to evaluate the effects of adding Korean rice wine residue (RWR) in total mixed ration (TMR) on in vitro ruminal fermentation and growth performance of growing Hanwoo steers. Methods: For in vitro fermentation, the experimental treatments were Control (Con: 0 % RWR + TMR), Treatment 1 (T1: 10 % RWR + TMR), and Treatment 2 (T2: 15 % RWR + TMR). The rumen fluid was collected from three Hanwoo steers and mixed with buffer solution, after which buffered rumen fluid was transferred into serum bottles containing 2 g dry matter (DM) of TMR added with or without RWR. The samples were then incubated for 0 h, 12 h, 24 h, or 48 h at $39^{\circ}C$ and 100 rpm. For the in vivo experiment, 27 Hanwoo steers (6 months old) with an average weight of $196{\pm}8.66kg$ were subjected to a 24-week feeding trial. The animals were randomly selected and equally distributed into three groups. After which the body weight, feed intake and blood characteristics of each group were investigated. Results: The pH of the treatments decreased significantly relative to the control during the 12 h of incubation. Total gas production and ammonia nitrogen ($NH_3-N$) was not affected by RWR addition. The total volatile fatty acid (VFA) was lower after 24 h of incubation but at other incubation times, the concentration was not affected by treatments. Feed cost was 8 % and 15 % lower in T1 and T2 compared to control. Blood alcohol was not detected and a significant increase in total weight gain and average daily gain were observed in Hanwoo steers fed with RWR. Conclusion: Overall, the results of this study suggest that TMR amended with 15 % RWR can be used as an alternative feed resource for ruminants to reduce feed cost.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1127-1133
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• 1998

Background: There are no ideal substitutes for tracheal replacement. Therefore we investigated the possibility of clinical use of cryopreserved tracheal homograft with special interest in the viability and rejection of the epithelial cell and cartilage. Material and Method: Rabbit's trachea was sected and stored in liquid nitrogen tank for 1 month. Tracheal replacement was done in 45 rabbits with autograft(n=15, Group 1), fresh allograft(n=15, Group 2) and cryopreserved homograft(n=15, Group 3). After 7, 14, and 30 days, 5 rabbits in each group were sacrificed and the regeneration of epithelium and cartilage and the degree of rejection were assessed by counting the monocellular infiltration. Result: Investigation at day 7, showed no difference in epithelial regeneration, however, at days 14 and 30, Group 1 showed better regeneration of epithelium than groups 2 and 3. There was no difference of epithelial regeneration between group 2 and 3. There was little rejection at day 7, but at days 14 and 30, there was significant rejection in group 2 and group 3.(P<0.05). Group 3 showed lesser rejection than group 2 at days 14 and 30, but it was not statistically significant. Cartilage showed no rejection and maintained its viability in groups 2 and 3. Conclusion: Cryopreserved tracheal homograft can maintain its viability, therefore it may represent a possibility of clinical application for tracheal replacement. However, cryopreservation can not eliminate the antigenicity of the trachea completely. Furthere studies for lowering the antigenicity and rejection should be performed for an ideal substitute for tracheal replacement.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.99-110
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• 2007

Efficient and inexpensive hydrogen storage is an essential prerequisite for the utilization of hydrogen, one of the new and clean energy sources for $21^{st}$ century. In this review, several storage techniques are briefly reviewed and compared. Especially, adsorption/storage via physisorption at low temperature, by using nanoporous adsorbents, is reviewed and evaluated for further developments. The adsorption over a porous material at low temperature is currently investigated deeply to fulfill the storage target. In this review, several characteristics needed for the high hydrogen adsorption capacity are introduced. It may be summarized that following characteristics are necessary for high storage capacity over porous materials: i) high surface area and micropore volume, ii) narrow pore size, iii) strong electrostatic field, and iv) coordinatively unsaturated sites, etc. Moreover, typical results demonstrating high storage capacity over nanoporous materials are summarized. Storage capacity up to 7.5 wt% at liquid nitrogen temperature and 80 atm is reported. Competitive adsorbents that are suitable for hydrogen storage may be developed via intensive and continuous studies on design, synthesis, manufacturing and modification of nanoporous materials.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.196-200
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• 2002

Lower field germination was observed in lipoxygenase- lacking soybean genotypes. This study was performed to understand seed-related traits after accelerated aging in response to planting date of soybeans. Two soybean cultivars, Jinpumkong (null lipoxygenase-2,3) and Jinpumkong 2 (lacking lipoxygenase-1, 2, 3) were evaluated for germination, and were compared with the cultivar, Taekwangkong containing lipoxygenase-1,2,3 isozymes. Greater seed coat cracking was shown in Jinpumkong and Jinpumkong 2 than Taekwangkong. Regardless of soybean genotypes, earlier planting resulted in greater seed coat cracking. After accelerated aging, seed fracturability and hardness of Jinpumkong and Jinpumkong 2 were lower than those of Taekwangkong. There was significant difference in germination percentage among soybean genotypes in response to planting date. Seeds obtained from late planting showed better germination ability. Accelerated aging resulted in lower germination percentages of Jinpumkong and Jinpumkong 2 than that of Taekwangkong, and showed higher electric conductivity in Jinpumkong and Jinpumkong 2 than Taekwangkong. After accelerated aging at 4$0^{\circ}C$ for thirty five days, germination percentages of Jinpumkong and Jinpumkong 2 were lower than that of Taekwangkong. Electric conductivity was increased continually as accelerated aging time became longer, and Jinpumkong and Jinpumkong 2 showed higher electric conductivity than Taekwangkong. Even though there were significant genotype differences in seed traits, further studies are needed to determine whether seed lipoxygenase ability is associated with germination ability.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.190-196
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• 2007

This study was carried out to investigate the effects of pressure assisted freezing(PAF) on physicochemical properties of pork meat. Pork meat was frozen under pressure up to 200 MPa at $-60^{\circ}C$, and compared with fresh control. Phase transition temperature decreased with increasing pressure level, while pressure level had no effect on supercooling extent. Increasing pressure level increased pH of meat significantly(p<0.05). Thawing losses of all treatments were significantly higher(p<0.05) than control with the exception of PAF at 200 MPa. Water holding capacity(WHC) was increased significantly(p<0.05) with increasing pressure level up to 100 MPa. Cooking loss tended to decrease with increasing pressure level. In color, CIE $L^*-\;and\;b^*-value$ increased with increasing pressure level, while CIE $a^*-value$ decreased significantly(p<0.05). Increasing pressure level up to 150 MPa increased shear force significantly(p<0.05), however, no significant difference between 150 and 200 MPa in shear force was found(p>0.05). Therefore, the results indicated that excessive pressure level in PAF caused several losses in meat qualities, while PAF at mild pressure level improved meat qualities compared to atmosphere freezing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1579-1585
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• 2005

The aim of this study was to propose utilization of tofu whey concentrates separated by ultrafiltration (UF) for yogurt production. The curd yogurt was prepared from whole milk added with skim milk Powder in which UF powder was substituted 0$\%$, 6.25$\%$, 12.5$\%$ or 25$\%$ for skim milk powder. The quality characteristics of yogurt in terms of pH, titratable acidity, viscosity, color and viable cell counts were evaluated. There were no significant differences in pH and titratable acidity between control (yogurt added with only skim milk powder) and yogurt added with UF powder after 24 hr of fermentation at 37$^{\circ}C$. Apparent viscosity of yogurt added with UF powder was lower (2,623 $\∼$ 3,189 cps) than that of the control yogurt (3,196 cps). Lightness and redness value of yogurt added with UF powder were not significantly different from control yogurt, while yellowness value increased as the amount of UF powder increased. Addition of UF powder stimulated the growth of lactic acid bacteria. Gas chromatographic analysis detected acetaldehyde, diacetyl, and organic acids, and more volatile compounds were detected in yogurt added with UF powder. Sensory analysis showed that yogurt added with UF powder were evaluated as acceptable as control yogurt. Therefore, UF powder could be substituted for skim milk powder without depressing yogurt qualify.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.49-49
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• 2009

마찰교반접합법은 특정한 회전수로 회전하는 용접 툴을 이용하여 접합하고자 하는 피접합재의 맞댄면에 삽입시킨 후 툴을 이동시키거나 혹은 시편을 견고하게 고정시킨 장치(backing plate)가 움직여 고상 상태에서 접합이 이루어진다. 알루미늄, 마그네슘 등 비교적 융점이 낮은 저융점 재료의 재료에 처음 적용이 되어 많은 연구가 활발히 진행되었고 타 용접방법에 비해 우수한 접합특성을 나타내었다. 최근 이러한 마찰교반접합은 이러한 저융점 재료를 넘어서 스틸, 타이타늄, 니켈 등과 같은 고융점 재료 등에 대한 적용이 늘어나고 있다. 마찰교반접합을 이용하여 이러한 고융점 재료의 접합 경우 내마모성 및 내열성 등의 내구성이 갖추어진 툴과 이러한 툴을 냉각시킬 수 있는 냉각 장치 등이 필요로 하나 경제적 측면이나 접합부의 우수한 특성 등을 고려 할 때 그 적용 및 발전 가능성이 매우 높다고 볼 수 있다. 최근 무공해 연료로 각광받고 있는 액화천연가스 (LNG)의 수요가 급증함에 따라 LNG 저장탱크 소재로 널리 사용되고 있는 9% Ni강의 수요 또한 증가하고 있는 상황이다. 하지만 9% Ni 강은 극저온용 소재로 용접부의 저온인성 ($-196^{\circ}C$)이 가장 중요하기 때문에 저온인성을 확보하고자 Inconel 계나 Hastelloy계 등의 니켈 기 합금을 용접재료로 사용하고 있으나 이러한 용접재료는 가격이 매우 고가이며 또한 용접 후 용접부의 강도가 낮다는 문제가 제기되고 있다. 또한 LNG 탱크 제작시 사용되는 용접법은 GTAW, SAW 및 SMAW 이지만 국내에서는 주로 SMAW에 의존하고 있는 실정인 관계로 보다 더 경제적인 용접 프로세스의 적용 가능성이 검토되고 있는 상황이다. 본 연구에서는 마찰교반용접을 이용하여 두께 4mm의 9% Ni 강에 대해 맞대기 마찰교반접합을 실시하였다. 툴 회전 속도 및 접합 속도를 고정한 상태에서 접합을 실시 하였으며 접합 시 툴은 $Si_3N_4$로 제작된 툴을 사용하였다. 접합 후 외관상태 점검, 미세조직 관찰, 경도, 인장 강도 및 저은 충격 측정 등의 실험을 실시하였고, 이러한 결과를 이용하여 미세조직과 기계적 특성과의 관련성을 조사하였다.

• Journal of Environmental Science International
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• v.23 no.10
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• pp.1703-1718
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• 2014

An eco-friendly integrated multi-trophic aquaculture (IMTA) farming technique was developed with the goal of resolving eutrophication by excess feed and feces as fish-farming by-products. A variety of seaweed species were tried to remove inorganic nutrients produced by fish farming. However, there have been few trials to use Sargassum fulvellum in an IMTA system, a species with a relatively wide distribution across regions with various habitat conditions, great nutrient removal efficiency and importance for human food source and industrial purposes. In this regard, our study tried to examine feasibility of using S. fulvellum in an IMTA system by analyzing growth characteristics of the species in an IMTA system comprising of rockfish (Sebastes shlegeli), sea cucumber (Stichopus japonocus) and the tried S. fulvellum (October 2011 - November 2012). We also monitored environment conditions around the system including current speed, water temperature and inorganic nutrient level as they may affect growth of S. fulvellum. S. fulvellum in the IMTA system, which were $15.72{\pm}5.67mm$ long at the start of the experiment in October 2011, grew to a maximum of $1093{\pm}271.13mm$ by May 2012. In September, seaweed growth was reduced to a minimum of $280{\pm}70.43mm$ in length. Then, S. fulvellum began to grow again reaching $325{\pm}196.19mm$ by November 2012. Wet weight of the seaweed was $4.01{\pm}1.89g$ at the start of the experiment and reached a maximum of $109.26{\pm}34.23g$ in May. The weight gradually declined to a low of $15.12{\pm}8.40g$ in September 2012. Weight began to increase once more, rising to $39.27{\pm}21.69g$ by November. During the experiment, the average velocity at the surface and the bottom was 6.5 cm/s and 3.4 cm/s, respectively. The water temperature ranged $5.0-23.5^{\circ}C$, which was considered suitable for growing S. fulvellum. Results of the study indicated no significant differences in inorganic nutrients between pre- and post-IMTA installation. It was thus concluded that S. fulvellum can be a suitable seaweed species to be used in an IMTA system.

• Korean Journal of Plant Resources
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• v.14 no.3
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• pp.196-205
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• 2001

The results of examining cultivation of tlyster mushroom using NSM(Non Sterilized Media) for determining the condition of artificially culturing oyster mushroom(Pleurotus ostreatus) are as follows. Mycelial growth an[1 density of oyster mushroom. were the highest in the medium of waste cotton(spinning) : corn cob(80 : 20, V/V) followed by the order of rice bran, beet pulp. Expecially, mycelial growth and density of oyster mushroom is the lowest at the mixture rate of 80% waste cotton(spinning) : 10% beet pulp. Mycelial growth and density of oyster mushroom. were the highest in the medium of cotton seed hull and beet pulp mixture followed by the order of rice bran, corn cob. Expecially, mycelial growth and density of oyster mushroom is the lowest at the mixture rate of 80% cotton seed hull : above 20% rice bran. Mycelial growth and density of oyster mushroom were the highest in the medium rate of 70% waste cotton(spinning), 10% corn cob and 10% beet pulp(V/V). Mycelial growth and density of oyster mushroom were the highest in the medium rate of 70% cotton seed hull , 10% corn cob and 10% beet pulp(V/V). Optimal concentration of NSM for the mycelial growth and density of oyster mushroom were shown to be 500 times concentration. Optimal water contents for the mycelial growth and density of NSM was 70%.

• The Korean Journal of Ecology
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• v.24 no.3
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• pp.157-168
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• 2001

Herbicides have been used to control weeds for decades. If detoxification upon exposure to herbicides requires considerable amounts of energy, it could affect the pattern of resource allocation to growth and reproduction of crops. We examined the effects of three levels of a herbicide (Control, Low, and High) on germination, growth and reproductive characters of Glycine max treated twice, i.e., before and after seed germination. Since flowering time of G. max was separated into two groups, flowering time was also considered as a variable in this study. The rate of seed germination tended to be higher at the low level of herbicide compared to other levels. Chlorosis and shape variation of leaves were apparent after the second herbicide treatment, but completely disappeared after six weeks of treatment. The herbicide effects on growth characters were somewhat different between early and late flowering plants, but plants treated with both low and high levels of herbicide reduced their growth compared to those in the control group regardless of flowering time. Plants at the high level of herbicide exhibited the highest growth rate later in the season, suggesting that plants compensated to some extent for reduced growth. However, growth reduction among plants at the high level of herbicide was persistent until the end of growing season. Among plants flowered late in the season, plants in the control level bore a higher number of nodules per plant than those in other levels; such a pattern did not exist among plants flowered early in the season. Plants treated with low and high levels of herbicide produced a lower number of flowers than those in the control. Thus, the herbicide examined affected not only the growth and reproductive characters of non-target crops but also the development and growth of root nodules.