• Journal of the Korean Society of Industry Convergence
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• v.24 no.6_1
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• pp.683-691
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• 2021

Bipolar plates with channel width of 0.5 mm, 0.4 mm, and 0.3 mm respectively were printed using a 3D printer. The shape of three b ipolar plates was rectangular, the channel depth was 0.5 mm, and the thickness of base was 0.5 mm. The bipolar plate with channel width of 0.5 mm had 45 channels, and their active area was 44.5 mm × 50 mm. The bipolar plate with channel width of 0.4 mm had 57 channels and its active area was 45.2 mm × 50 mm, and the bipolar plate with channel width of 0.3 mm had 75 channels and its active area was 44.7 mm × 50 mm. The bipolar plates were printed using PLA filament. The cross-sectional lengths of the bipolar plates with channel widths of 0.5 mm and 0.4 mm were identical by 96% of the designed cross-sectional length. Whereas the bipolar plate with a channel length of 0.3 mm had a large difference of 25% from the designed cross-sectional length.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.3
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• pp.248-261
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• 2021

Scientific and technological performances (e.g., patents and publications) made through R&D play a pivotal role for national economic growth. National governments encourage academia-industry cooperation and thereby pursue continuous development of science technology and innovation. Increasing R&D-related investments and manpower are crucial for national industrial development, but evidence of poor performance in business performance, efficiency, and effectiveness has recently been found in Korea. This study evaluates performance efficiency of the 6T sector (Information Technology, Bio Technology, Nano Technology, Space Technology, Environment Technology, Culture Technology), which is considered a high-potential promising industry for the next generation growth and currently occupies two thirds of the national R&D projects. The study measures the relative efficiency of R&D in a comparative perspective by employing the Data Envelopment Analysis (DEA) method. The result reveals overall low efficiency in basic R&D (0.2112), applied R&D (0.2083), development R&D (0.2638), and others (0.0641), confirming that economic performance and efficiency were relatively poor compared to production efficiency. Efficient R&D needs policy makers to create strategies that can increase overall efficiency by improving productivity performance and quality while increasing economic performance.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.106-115
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• 2018

Objective: The goal of this study was to investigate the effects of dietary standard ileal digestible (SID) valine:lysine ratios on performance, intestinal morphology, amino acids of liver and muscle, plasma indices and mRNA expression of branched-chain amino acid (BCAA) metabolism enzymes. Methods: A total of 144 crossbred pigs (Duroc${\times}$Landrace${\times}$Large White) weaned at $28{\pm}4days$ of age ($8.79{\pm}0.02kg$ body weight) were randomly allotted to 1 of 4 diets formulated to provide SID valine:lysine ratios of 50%, 60%, 70%, or 80%. Each diet was fed to 6 pens of pigs with 6 pigs per pen (3 gilts and 3 barrows) for 28 days. Results: Average daily gain increased quadratically (p<0.05), the villous height of the duodenum, jejunum and ileum increased linearly (p<0.05) as the SID valine:lysine ratio increased. The concentrations of plasma ${\alpha}-keto$ isovaleric and valine increased linearly (p<0.05), plasma aspartate, asparagine and cysteine decreased (p<0.05) as the SID valine:lysine ratio increased. An increase in SID lysine:valine levels increased mRNA expression levels of mitochondrial BCAA transaminase and branched-chain ${\alpha}-keto$ acid dehydrogenase in the longissimus dorsi muscle (p<0.05). Conclusion: Using a quadratic model, a SID valine:lysine ratio of 68% was shown to maximize the growth of weaned pigs which is slightly higher than the level recommended by the National Research Council.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.3
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• pp.395-399
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• 1999

Three experiments were conducted to determine the effects of conditioning a complex (20% whey, 10% lactose, 4% plasma protein, 4% wheat gluten and 2% blood meal) diet on growth performance of weanling pigs. In Exp. 1,180 pigs (average initial BW of 6.4 kg) were fed the experimental diet (1.7% lysine) during a 7-d growth assay. Treatments were a meal control (M), standard (ST), and expander (EX) conditioned mash or pellets. Rate and efficiency of gain were decreased by 39% and 21% (p<0.005) respectively, for pigs fed EX diets compared to those fed the ST diet. In Exp. 2,196 pigs (average initial BW of 6.5 kg) were used to determine the effects of EX operating conditions on nutritional value of a pelleted complex diet. When steam conditioning temperature (prior to expanding) was $54^{\circ}C$, increasing cone pressure of the EX from 0 to 7 to 14 kg/cm2 resulted in linear decreases in rate of gain of weaned pigs (p<0.006), suggesting heat damage of the diet. Increasing conditioning temperature (i.e., adding steam) of the diets from 46 to 54 to $63^{\circ}C$ (cone pressure at $12kg/cm^2$) resulted in improved rate of gain (p<0.04) of the pigs. However, none of the pigs fed expanded diets compared favorably to the pigs fed the conditioned $(54^{\circ}C)$ pellets processed with no cone pressure. In Exp. 3,168 pigs (average initial BW of 6.6 kg) were used to determine the effects of expanding the various components of the diet. Treatments were M and ST pellets as controls, EX-corn, EX-corn soybean-meal, EX corn-soybean meal-oil, and EX-complete diet. Efficiency of gain was increased by 13% with EX portions of the diet compared to the mash control, but there was a marked decrease in performance when the complete diet was expanded (p<0.001). Expanded corn-soybean meal-oil supported the greatest ADG with a 19% increase compared to the average of the EX corn and EX corn-soybean meal treatments (p<0.005). In conclusion, our results suggest no benefit from expanding complete phase-I diets.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.449-455
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• 1993

Vibrio vulnificus is a recentry recognized halophilic organism that may cause human infections. Patients infected with Vibrio vulnificus often have a history of exposure to the sea, suggesting that the organism may be common inhabitant of marine environment. In this studies 314 samples were collected from 9 sites of Chonnam coastal area, from April to Jun, 1993. Isolation rates of V. vulnificus were 7.1% in total samples, 33.3% in sea water, 55.5% in sediment, 1.7% in fish and shellfish, 6.3% in kitchen environment. In each areas of Chunnam V. vunificus were isolated from 3.6% to 11.4%. The isolation rates of V. vulnificus was correlated positively with organic matter and COD in sea warer and sediment. In sea water, Microorganism population were $4.5{\times}10^3{\sim}3.5{\times}10^5\;CFU/ml$, Vibrio strains were $1.8{\times}10^l4.6{\times}10^3\;CFU/ml$, Coliform bacteria were $1.9{\times}10^1{\times}3.7{\times}10^2\;CFU/100ml$. In sediment, Microorganism population were $4.8{\times}10^3{\sim}5.2{\times}10^5\;CFU/ml$. Vibrio strains were $1.9{\times}10^2{\sim}8.4{\times}10^4\;CFU/ml$, Coliform bacteria were $7.2{\times}10^1{\sim}9.9{\times}10^2\;CFU/100ml$.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.102-110
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• 2015

The purpose of this experiment was to determine and compare the digestibility of crude protein (CP) and amino acids (AA) in full-oil (no oil extracted) and de-oiled (oil extracted) corn distillers dried grains with solubles (DDGS) with different condensed distillers solubles (CDS) ratios. Six barrows ($29.6{\pm}2.3kg$) fitted with ileal T-cannula were allotted into a $6{\times}6$ Latin square design. Each period was comprised of a 5-d adaption period followed by a 2-d collection of ileal digesta. The five test diets contained 62% DDGS as the sole source of AA. A nitrogen-free diet was used to measure the basal endogenous losses of CP and AA. Chromic oxide (0.3%) was used as an index in each diet. The results showed that CP and AA were very similar in 5 DDGS, but the standardized ileal digestibility (SID) of lysine (from 56.16% to 71.15%) and tryptophan (from 54.90% to 68.38%) had the lowest values and largest variation within the essential AA, which suggests reduced availability of AA and different levels of Maillard reactions in the five DDGS. The apparent ileal digestibility and SID of CP and most of AA in full-oil DDGS (sources 1 and 2) were greater (p<0.05) than de-oiled DDGS (sources 3, 4, and 5). Comparing the AA SID in the 5 DDGS, full-oil with low CDS ratio DDGS (source 1) had non-significantly higher values (p>0.05) than full-oil with high CDS ratio DDGS (source 2); however, the SID of most AA of de-oiled with low CDS ratios DDGS (source 3) were non-significantly lower (p>0.05) than de-oiled with high CDS ratio DDGS (source 4); and the de-oiled DDGS with middle CDS ratio (source 5) but with different drying processing had the lowest SID AA values. In conclusion, de-oiled DDGS had lower SID of CP and AA than full-oil DDGS; a higher CDS ratio tended to decrease the SID of AA in full-oil DDGS but not in de-oiled DDGS; and compared with CDS ratio, processing, especially drying, may have more of an effect on AA digestibility of DDGS.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.6
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• pp.350-355
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• 2007

The optimal substrates and reaction flavoring conditions were examined to develop pearl oyster extract (POE) flavor using the Maillard reaction under a model system. The sugar for the Maillard reaction was glucose, and the amino acid was cysteine, with glycine as the reaction substrate. A three-dimensional response surface method was used to monitor the dynamic changes of the substrates during the Maillard reaction. To enhance the flavor of POE, a two-step enzymatic hydrolysate (Brix $20^{\circ}$) was reacted with the precursors (1:1, v/v). A 2:1:1 mixture of 0.4 M glucose:0.4 M glycine:0.4 M cysteine (v/v) was selected as a suitable reaction system for the reappearance of baked potato odor and boiled meat odor, and masking the shellfish odor. The two-step enzymatic hydrolysate and selected precursors were reacted in a high-pressure reactor to optimize the reaction parameters. The optimum conditions were 150 minutes at $120\;^{\circ}C$ and pH 7.0. The pH was the most critical factor for the response of the baked potato odor and masking the shellfish odor, while the reaction time affected the reappearance of the boiled meat odor.

• International Commerce and Information Review
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• v.16 no.4
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• pp.55-75
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• 2014

Non-parametric method such as technology efficiency, DEA/Window model and Malmquist Productivity Index (MPI) are used to measure efficiency and productivity of ICT (Information and Communication Technology) manufacturing industry and service industry over the period 2007-2011. The results of this paper indicate following: (1) Technology efficiency of the ICT manufacturing industry were found as the range of 0.34 and 0.39 over the sample period. Technology efficiency of the ICT service industry were found as the range of 0.16 and 0.20 over the sample period. (2) The geometric average of the Malmquist TFP indexes on ICT manufacturing industry indicated the productivity improvement an average of 8.3 percent. The geometric average of the Malmquist TFP indexes on ICT service industry indicated the productivity improvement an average of 1.6 percent. (3) TIER analysis result on ICT manufacturing industry showed that optimal bench marking made by storage devices${\rightarrow}$wireless communication equipment${\rightarrow}$broadcasting equipment${\rightarrow}$radio, recording and playback devices${\rightarrow}$computers, printers, video and audio-visual equipment path. TIER analysis result on ICT service industry indicated that optimal bench marking made by computers and packaged software${\rightarrow}$wired communication${\rightarrow}$communication, information, detection equipment${\rightarrow}$consulting and construction for computer systems integration${\rightarrow}$industrial machinery and equipment rental${\rightarrow}$telecommunications reseller${\rightarrow}$system software development and delivery${\rightarrow}$hosting path.

• Fisheries and Aquatic Sciences
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• v.9 no.2
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• pp.49-56
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• 2006

We evaluated changes in the nutritional composition of Mideodeok Styela clava harvested during the months of January, March, and May 2005. Glutamic acid, aspartic acid, arginine, leucine, and lysine were the most dominant amino acids present. Ratios of essential amino acids to nonessential amino acids were comparable to those of many fish species, with values ranging from 0.55 to 0.61 and 0.66 to 0.67 for muscle of Mideodeok from Geoje and Tongyeong, respectively. Mideodeok seems to be a suitable source of important fatty acids as it contains high levels of polyunsaturated fatty acids. Eicosapentanoic acid EPA; 20:5n-3 and docosahexanoic acid DHA; 22:6n-3 were the most dominant fatty acids, ranging from 20.0 to 22.3% and 16.5 to 17.9% in muscle, and 20.3 to 23.2% and 15.2 to 18.8% in tunic, respectively. The total mineral fraction of Mideodeok was 22.2-27.3% of dry matter. Sodium, calcium, magnesium, and potassium were the most dominant minerals in both muscle and tunic.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.1 s.109
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• pp.38-46
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• 2005

This study was focused on the optimum culture condition in CMCase, FPase and xylanase activities of two fungal strains that secret extracellular enzymes for using enzymatic deinking agent to old newsprint. The results of this study were as follows. When Fusarium pallidoroseum was grown on the medium, containing of rice bran+xylan $2.0\%,\;peptone\;0.6\%,\;KH_2PO_4\;0.075\%\;and\;MnSO_4\;0.06\%\;with\;pH\;9.0,\;at\;29^{\circ}C$ for 6 days, the quantitative degree of extracellular enzyme production was the highest. Optimum culture condition for Aspergillus niger was pH 5.0, $27^{\circ}C$ incubating temperature and 7 days incubation period on liquid medium, containing of CMC+xylan $2.5\%,\;yeast\;extract\;0.4\%,\;K_3PO_4\;0.05\%\;and\;CaCl_2+FeSO_4\;0.08\%$. Aspergillus niger was fairly higher FPase and xylanase activities than Trichoderma reesei ATCC 28217.