• Asian-Australasian Journal of Animal Sciences
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• 제27권12호
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• pp.1736-1743
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• 2014

This study was designed to test the effects of dietary distillers dried grain (DDG) level on the growth performance, feed utilization, body composition and antioxidant activity of juvenile red seabream (Pagrus major). Six isonitrogenous and isocaloric diets were formulated to contain 0%, 5%, 10%, 15%, 20%, and 25% DDG from rice (designated as DDG0, DDG5, DDG10, DDG15, DDG20, and DDG25), respectively. Juvenile red seabream averaging $10.1{\pm}0.05g$ were randomly distributed into 400-L tanks in a flow through systems. Three replicate groups of fish were fed one of the experimental diets to visual satiation two times a day for 10 weeks. Survival, weight gain, feed efficiency, protein efficiency ratio and hepatosomatic index of fish were not affected by dietary DDG levels (p>0.05). Proximate and amino acid composition of whole body in juvenile red seabream were not affected by dietary DDG levels (p>0.05). Plasma content of total protein, glucose, cholesterol, glutamic-pyruvic transaminase, phospholipid and triglyceride were not affected by dietary DDG levels (p>0.05). 1, 1-Diphenyl-2-picryl-hydrazyl radical and alkyl radical scavenging activities in plasma and liver of fish were not affected by dietary DDG levels (p>0.05). The results of this experiment suggest that DDG has the potential to replace plant origin ingredients such as wheat flour and corn gluten meal and could be used up to 25% in diet without incurring negative effects on the growth performance of juvenile red seabream.

• 기술혁신연구
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• 제10권1호
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• pp.98-123
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• 2002

This study develops a Korean R&D Scoreboard which has originated from the R&D Scoreboard in United Kingdom. The Scoreboard contains details of the R&D investment, sales, growth, profits and employee numbers for Korean companies which are extracted from company annual reports and key ratios calculated, with some movements over time. Companies are classified by the Korea Standard Industrial Classification. The Scoreboard contains 190 companies which consist of 100 largest companies and 30 middle-or small-sized firms listed in Korea Stock Exchange (KSE), and 30 ventures and 30 other firms listed in KOSDAQ. The overall company R&D intensity (R&D as a percentage of sales) is 2.1% compared to the international average of 4.2%. Korea has an unusually large R&D percentage of sales in IT hardware (4.9%) and telecommunication (3.7%). R&D intensity is positively correlated with company performance measures such as profitability, sales growth, productivity and market value. For largest companies listed in KSE and ventures listed in KOSDAQ, the ratio of operating profit to sales is greater for high R&D intensity companies. Sales growth is in proportion to R&D intensity for all companies. Plots of value added per employee or sales per employee vs R&D per employee rise together for the sectors studied, especially for the chemical sectors and automobile sectors, demonstrating a correlation with productivity. The average market value of high R&D companies in the KSE has risen more than 1.6 times that of the KOSPI 200 index. Given the correlation between R&D intensity and company performance and given that R&D is a smaller percentage of surplus (profits plus R&D) than international level (both overall and in several sectors), the challenges facing Korean companies are to maintain the leading position in IT hardware and telecommunication, and to increase the intensity of R&D in many medium-intensive R&D sectors where Korea has an average intensity well below international or US levels.

• Structural Engineering and Mechanics
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• 제81권5호
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• pp.565-574
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• 2022

The infrastructures such as offshore, bridges, power plant, oil and gas piping and aircraft operate in a harsh environment during their service life. Structural integrity of engineering components used in these industries is paramount for the reliability and economics of operation. Two regression models based on the concept of Gaussian process regression (GPR) and Minimax probability machine regression (MPMR) were developed to predict stress intensity factor range (𝚫K). Both GPR and MPMR are in the frame work of probability distribution. Models were developed by using the fatigue crack growth data in MATLAB by appropriately modifying the tools. Fatigue crack growth experiments were carried out on Eccentrically-loaded Single Edge notch Tension (ESE(T)) specimens made of API 5L X65 Grade steel in inert and corrosive environments (2.0% and 3.5% NaCl). The experiments were carried out under constant amplitude cyclic loading with a stress ratio of 0.1 and 5.0 Hz frequency (inert environment), 0.5 Hz frequency (corrosive environment). Crack growth rate (da/dN) and stress intensity factor range (𝚫K) values were evaluated at incremental values of loading cycle and crack length. About 70 to 75% of the data has been used for training and the remaining for validation of the models. It is observed that the predicted SIF range is in good agreement with the corresponding experimental observations. Further, the performance of the models was assessed with several statistical parameters, namely, Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Coefficient of Efficiency (E), Root Mean Square Error to Observation's Standard Deviation Ratio (RSR), Normalized Mean Bias Error (NMBE), Performance Index (ρ) and Variance Account Factor (VAF).

• Asian-Australasian Journal of Animal Sciences
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• 제30권8호
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• pp.1143-1149
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• 2017

Objective: The objective of the present study was to determine whether mango saponin (MS) could be used as a feed additive in broiler chicks by evaluating growth performance, carcass characteristics, meat quality, and plasma biochemical indices. Methods: A total of 216 1-d-old Arbor Acres male broiler chicks were randomly assigned into three dietary treatments supplemented with 0 (control), 0.14% (MS 0.14%), or 0.28% (MS 0.28%) MS. Each treatment had six replicates (cages) with 12 chicks each. The feeding trial lasted for six weeks. Results: Compared with the control, dietary supplemented with 0.14% or 0.28% MS increased average daily weight gain of chicks in the grower (22 to 42 d) and the whole (1 to 42 d) phases, and the final body weight of chicks on d 42 was higher in MS supplemented groups (p<0.05). Lower $L_{45min}{^{\star}}$ (lightness) and $L_{24h}{^{\star}}$ values, lower $b_{24h}{^{\star}}$ (yellowness) value, and higher $a_{45min}{^{\star}}$ (redness) and $a_{24h}{^{\star}}$ values of the breast muscle were observed in chicks fed with 0.28% MS on d 42 (p<0.05). The total antioxidant capacity in plasma increased in MS 0.14% group on d 21 (p<0.001). Lower contents of plasma total cholesterol and triglyceride were observed in chicks fed with 0.28% MS on d 21 and d 42, whereas the group supplemented with 0.14% MS only decreased plasma triglyceride content on d 21 (p<0.05). The glucose content in plasma decreased in MS 0.28% group on d 42 (p<0.001). Conclusion: Overall, MS could be used as a feed additive in broiler chicks, and the supplemental level of 0.28% MS in diet could improve growth performance, meat quality, and plasma lipid metabolism in broiler chicks.

• Asian-Australasian Journal of Animal Sciences
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• 제33권5호
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• pp.802-811
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• 2020

Objective: Two experiments were conducted to investigate the effects of dietary sucralose on diet preference and growth performance of weaned piglets, and a third experiment was a 28-d safety study to examine if high-dose sucralose could affect the health state of weaned piglets. Methods: In experiment one, 48 piglets had free access to a corn-soybean based diet and the same diet supplemented with 150 mg/kg sucralose for 15 d. In experiment two, 180 piglets were blocked into 5 treatments with 6 replications. They were fed basal diets supplemented with 0, 75, 150, 225, and 300 mg/kg sucralose for 28 days. In experiment three, 108 piglets were randomly assigned to 3 treatments and fed diets supplemented with 0, 150 (suitable level), and 1,500 (ten-fold suitable level) mg/kg sucralose for 28 d. Results: The experiment 1 showed that piglets preferred (p<0.05) diets containing sucralose during experimental period. In experiment 2, piglets fed a diet supplemented with 150 mg/kg sucralose had a higher average daily gain (ADG) and average daily feed intake (ADFI) than pigs in the control group and other treatment groups during the experiment period. The concentrations of sucralose over 150 mg/kg may decrease feed intake. However, no difference in feed conversion ratio was observed. In experiment 3, piglets fed diet supplemented with 150 mg/kg sucralose had a higher ADG and ADFI than that of pigs in the control group and 1,500 mg/kg treatment groups during the experiment period. Clinical blood metabolites, organ index and histological morphology were not significantly different between sucralose treatments. Conclusion: Sucralose can promote feed intake and thereby improve growth performance of weaned piglets. Moreover, inclusion of 1,500 mg/kg sucralose was demonstrated to have no observed adverse effects. Supplementing 150 mg/kg sucralose for weaned piglets is recommended in this study.

• 생명과학회지
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• 제22권1호
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• pp.36-40
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• 2012

본 연구는 한우 암소의 산육 및 도체특성에 있어 오징어 부산물의 급여 효과를 알아보기 위해 수행되었다. 한우 16두(나이 7세, 체중$484.1{\pm}63.6$ kg)를 대조구 및 처리구(오징어 부산물 첨가), 등 2그룹(각각 8두)으로 완전임의 배치하였다. 사료급여는 두 그룹 모두 자유채식토록 하여 150일간 시험을 수행하였다. 일당증체량은 처리구가 대조구 보다 유의적으로 높았다(p<0.05). 시험기간 내 사료섭취량 및 사료요구율은 처리구가 대조구 보다 유의적으로 낮았다(p<0.05). 육량특성에 있어서, 등지방두께, 등심단면적 및 육량지수는 두 처리구간 비슷한 경향을 나타내었고, 도체중은 처리구가 363.4 kg 대조구 353.1 kg으로 처리구간 유의적 차이는 없었다. 육질특성에서는 육색, 지방색, 조직감 및 성숙도는 두 그룹간 유의적 차이가 없었다. 그러나 근내지방도 및 육질 1등급 이상 출현율은 대조구 보다 처리구가 높았다. 그러므로 본 연구의 결과 오징어부산물의 급여는 한우 암소의 산육 및 도체특성을 향상시키는 것으로 생각된다.

• 한국자원식물학회지
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• 제20권1호
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• pp.7-11
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• 2007

우량품종 육성을 위해 선발된 헛개나무 차대묘 20가계의 생장특성과 엽특성을 조사한 결과, 전체 평균 묘고는 61.6cm, 평균 근원직경은 6.98mm였으며, 가계별로는 KW 2-5 가계가 평균 묘고 79.3cm로 가장 우수한 생장을 보인 반면 근원직경에서는 JN 2-2 가계가 평균 9.16mm로 가장 우수한 생장을 나타내었다. 묘고와 근원직경에서 가장 우수한 생장을 보인 KW 2-5와 JN 2-2 가계는 가장 낮은 생장을 보인 가계들과 비교하여 각각 57%와 53%의 우수한 생장을 보였다. 묘고와 근원직경의 초기생장 상위 10% 가계를 선발했을 때 KW 2-5와 JN 2-2 가계가 전체 가계 평균에 비해 125%의 선발 효과를 보였으며, 상위 20% 가계를 선발했을 때 KW 2-5, JN 2-2, KW 1-1, KW 1-15 가계에서 115%의 선발효과를 나타냈다. 한편, 엽장과 엽폭, 엽병길이와 엽병직경 및 엽형지수와 측맥수 등 6항목에 대하여 엽특성을 조사한 결과, 평균 변이계수는 $9.4{\sim}42.4%$로 나타나 변이 폭이 큰것을 알 수 있었으며 특히, 엽병길이와 엽병직경 특성의 변이계수가 각각 42.4%와 28.7%로 다른 특성들에 비해 큰 값을 나타냈다. 조사된 엽특성들은 모두 가계간 유의적 차이가 인정되었으며, 엽장과 엽형지수간 상관을 제외한 모든 특성들간의 상관에서는 정의상관 관계가 인정되었고 특히, 엽장과 엽폭특성간의 상관계수가 0.8049로 나타나 두 특성간에 매우 유의적인 관계가 있는 것으로 나타났다.

• 한국산업정보학회논문지
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• 제25권6호
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• pp.15-23
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• 2020

기후 변화에 대응하기 위한 농업분야의 연구활동이 활발하게 이루어지고 있는 가운데 4차 산업혁명에 맞춰 정보통신기술을 활용한 스마트농업이 새로운 트랜드가 되었다. 이에 따라 다양한 노지 환경과 토양 조건에서 농작물의 스트레스를 모니터링하여 생육 이상 징후를 미리 식별하고 대응하려는 연구가 진행되고 있다. 다양한 센서를 거쳐 실시간으로 수집되는 데이터들을 인공지능 기법이나 빅데이터 기술을 활용하여 분석하려는 시도도 있다. 본 논문은 빅데이터 분석을 위해 기존 관계형 데이터베이스를 이용하여 농작물의 생육환경정보와 생체정보 분석에 효과적인 빅데이터 모델을 제안한다. 모델의 성능은 데이터 양에 따른 쿼리에 대한 응답 시간으로 측정하였다. 그 결과 최대 23.8%의 시간 단축 효과가 있음을 확인할 수 있었다.

• Structural Engineering and Mechanics
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• 제85권4호
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• pp.531-543
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• 2023

The existing concrete bridges are time-varying working systems, where the maintenance strategy should be planned according to the time-varying performance of the bridge. This work proposes a time-dependent residual capacity assessment procedure, which considers the non-stationary bridge load effects under growing traffic and non-stationary structural deterioration owing to material degradations. Lifetime bridge load effects under traffic growth are predicated by the non-stationary peaks-over-threshold (POT) method using time-dependent generalized Pareto distribution (GPD) models. The non-stationary structural resistance owing to material degradation is modeled by incorporating the Gamma deterioration process and field inspection data. A three-span continuous box-girder bridge is illustrated as an example to demonstrate the application of the proposed procedure, and the time-varying reliability indexes of the bridge girder are calculated. The accuracy of the proposed non-stationary POT method is verified through numerical examples, where the shape parameter of the time-varying GPD model is constant but the threshold and scale parameters are polynomial functions increasing with time. The case study illustrates that the residual flexural capacities show a degradation trend from a slow decrease to an accelerated decrease under traffic growth and material degradation. The reliability index for the mid-span cross-section reduces from 4.91 to 4.55 after being in service for 100 years, and the value is from 4.96 to 4.75 for the mid-support cross-section. The studied bridge shows no safety risk under traffic growth and structural deterioration owing to its high design safety reserve. However, applying the proposed numerical approach to analyze the degradation of residual bearing capacity for bridge structures with low safety reserves is of great significance for management and maintenance.

• 무역학회지
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• 제48권4호
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• pp.209-232
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• 2023

EU는 2030년 온실가스 배출량을 1990년 대비 55% 감축 목표로 하는 'Fit for 55' 입법 패키지에 국가별로 다른 온실가스 규제로 인한 수출품의 불균형한 가격을 조정하는 조치로 탄소국경조정제도(CBAM)를 2026년부터 시행하는 내용을 포함하였고, 이는 수출 비용의 증가를 가져와 우리나라 철강 제품 수출에 부정적인 영향을 미칠 것으로 예상된다. 본 연구는 철강 제품의 EU 수출에 영향을 주는 요인과 CBAM에 따른 수출 변화를 추정하기 위해 2001년부터 2021년까지 EU 27개 회원국의 통계를 이용하여 중력모형으로 실증 분석을 하였다. 분석 결과로 각 EU 국가의 경제 수준, 인구 규모, 환율, 제조업 생산지수, EU 단일시장의 효과는 우리나라 철강 제품의 수출 증가에 도움을 주지만, CBAM의 실행으로 2026년에 탄소세가 CO₂ 1톤당 USD 10 ~ USD 30이 부과되는 것을 가정하여 중력모형으로 추정한 결과는 철강 수출이 CBAM 시행 이전에 비해 약 -3.6% ~ -5.7% 감소하는 것으로 나타나 앞으로 철강 제품의 가격 경쟁력 향상과 CO₂ 저감을 위한 기업과 정부의 대비가 필요할 것으로 보인다.