• Journal of Radiation Protection and Research
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• 제40권1호
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• pp.10-16
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• 2015

성장기 동물에서 방사선 노출은 뼈의 변화를 일으킨다. 본 연구에서는 성장기 동물에서 방사선 유도 골소실 연구를 위한 동물모델을 확립하고자하였다. 성장기(4주령) 마우스에 방사선 노출(2 Gy) 후 시간경과(4, 8 및 12주)에 따른 경골 해면뼈 및 치밀뼈의 변화를 관찰하고, 방사선 비노출군과의 차이가 확연한 방사선 노출 후 8주에 방사선(0.5, 1.0, 2.0 및 4.0 Gy)을 조사하고 조사선량에 따른 변화를 관찰하였다. 동물의 희생 전 악력을 측정하였으며, 경골의 해면뼈 및 치밀뼈를 미세단층촬영 분석하였고, 해면뼈에서 뼈파괴세포의 활성도를 관찰하였다. 혈청내 alkaline phosphatase(ALP) 농도 및 경골의 물리적 강도를 측정하였다. 해면뼈의 확연한 차이는 8주에 관찰되었으며, 조사선량증가에 비례하여 해면뼈량(trabecular bone volume, BV/TV) 및 골밀도(bone mineral density, BMD)의 감소가 관찰되었다. 방사선조사선량에 따른 변화를 나타내는 이차방정식은 BV/TV (%) = $0.9584D^2-6.0168D+20.377$ ($r^2$ = 0.946, D = 방사선조사선량, Gy), $BMD(mg{\cdot}cm^{-3})=8.8115D^2-56.197D+194.41$ ($r^2$ = 0.999, D = 방사선조사선량, Gy) 였다. 뼈의 물리적 강도, 길이 및 무게의 변화는 없었으며, 혈청ALP 농도 및 뼈파괴세포 활성도도 차이가 없었다. 본 연구의 결과는 성장기 동물에서 방사선에 의한 뼈손상 연구에 동물모델 기초자료가 될 수 있을 것이다.

• Journal of Animal Science and Technology
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• 제47권4호
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• pp.501-512
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• 2005

본 시험은 약용식물(인진쑥, 오가피, 마늘)의 사료내 첨가가 모돈의 생산성, 포유자돈의 성장율 및 이유자돈에서의 성적 및 혈청 특성에 미치는 영향을 알아보고자 실시하였다. 시험 1은 3~5산차의 임신 모돈 48두를 공시하여 각각 1) CON(basal diet; Control), 2) MP1(basal diet added 0.05% of medicinal plant mixtures), 3) MP2(basal diet added 0.1% of medicinal plant mixtures) 그리고 4) MP3(basal diet added 0.2% of medicinal plant mixtures)로 하여 처리구당 12두씩 배치하여 21일동안 실시하였다. 시험 기간동안 포유모돈의 일당 사료섭취량은 약용식물을 0.1% 첨가한 처리구가 0.2%를 첨가한 처리구보다 유의적으로 높게 나타났다(P<0.05). 포유자돈의 개시시와 이유시의 체중 변화에서는 약용식물을 0.05% 첨가한 처리구가 대조구에 비하여 유의적으로 증가하는 경향을 보였다 (P<0.05). 혈액내 glucose의 함량에서는 MP3 처리구가 대조구에 비하여 유의적으로 높게 나타났다(P<0.05). 시험 2는 개시시 체중 4.70$\pm$0.63kg의 3원교잡종(Landrace$\time$Yorkshire$\time$Duroc) 이유자돈 120두를 공시하여 20일간 사양시험을 실시하였다. 시험설계는 옥수수－대두박 위주의 사료로서 NRC(1998)의 영양소 요구량에 따라 1) CON(basal diet; Control), 2) MP1(basal diet added 0.05% of medicinal plant mixtures), 3) MP2(basal diet added 0.1% of medicinal plant mixtures) 그리고 4)MP3(basal diet added 0.15% of medicinal plant mixtures)의 4개의 처리구로 하여 처리당 6반복, 반복당 5두씩 완전임의 배치하였다. 전체시험기간 동안의 이유자돈의 일당증체량(linear, P<0.067)과 사효효율(linear, P<0.018)에서는 약용식물을 첨가함으로서 증가하는 경향을 보였으며, 사료섭취량(linear, P<0.018)에서는 감소하는 경향을 보였다. 건물의 소화율에서는 약용식물을 첨가함에 따라 증가하는 경향을 보였다(linear, P<0.004; quadratic, P<0.03). 결론적으로 포유모돈 사료내 약용식물의 첨가는 0.1%까지 첨가 급여시가 모돈의 체손실 감소 및 포유자돈의 증체량의 향상을 가져 왔으며, 이유자돈에서는 약용식물을 0.05-1.0% 첨가시 자돈의 성장율 및 건물의 소화율을 개선시키는 결과를 보였다.

• 지능정보연구
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• 제25권4호
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• pp.53-65
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• 2019

영상 기반의 보안 시스템의 증가함에 따라 각 용도마다 다른 다양한 객체들에 대한 처리들이 중요해지고 있다. 객체 추적은 객체 인식, 검출과 같은 작업들과 함께 필수적인 작업으로 다뤄진다. 이 객체 추적을 달성하기 위해서 다양한 머신러닝이 적용될 수 있다. 성공적인 분류기로써 전체 에러율 최소화(total-error-rate minimization) 기반의 방법론이 사용될 수 있다. 이 전체 에러율 최소화 기반의 방법론은 오프라인 학습을 기반으로 하고 있다. 객체 추적은 실시간으로 처리하며 갱신해야하는 것이 필수적이므로 온라인 학습(online learning)을 기반으로 하는 것이 적합하다. 온라인 전체 에러율 최소화 방법론이 개발되었지만 점근적으로 재가중되는(approximately reweighted) 작업이 포함되어 에러를 누적시킬 수 있다는 단점이 있다. 본 논문에서는 정확하게 재가중되는(exactly reweighted) 방법론을 제안하면서 온라인 전체 에러율 최소화가 달성되었다. 이 제안된 온라인 학습 방법론을 객체 추적에 적용하여 총 8개의 데이터베이스에서 다른 추적 방법론들 보다 좋은 성능이 달성되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권5호
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• pp.696-704
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• 2018

Objective: This study was conducted to evaluate various levels of milk by-product in weaning pig diet on growth performance, blood profiles, carcass characteristics and economic performance for weaning to finishing pigs. Methods: A total of 160 weaning pigs ([Yorkshire${\times}$Landrace]${\times}$Duroc), average $7.01{\pm}1.32kg$ body weight (BW), were allotted to four treatments by BW and sex in 10 replications with 4 pigs per pen in a randomized complete block design. Pigs were fed each treatment diet with various levels of milk by-product (Phase 1: 0%, 10%, 20%, and 30%, Phase 2: 0%, 5%, 10%, and 15%, respectively). During weaning period (0 to 5 week), weaning pigs were fed experimental diets and all pigs were fed the same commercial feed during growing-finishing period (6 to 14 week). Results: In the growth trial, BW, average daily gain (ADG), and average daily feed intake (ADFI) in the nursery period (5 weeks) increased as the milk by-product level in the diet increased (linear, p<0.05). Linear increases of pig BW with increasing the milk product levels were observed until late growing period (linear, p = 0.01). However, there were no significant differences in BW at the finishing periods, ADG, ADFI, and gain:feed ratio during the entire growing-finishing periods. The blood urea nitrogen concentration had no significant difference among dietary treatments. High inclusion level of milk by-product in weaner diet decreased crude protein (quadratic, p = 0.05) and crude ash (Linear, p = 0.05) of Longissimus muscle. In addition, cooking loss and water holding capacity increased with increasing milk product levels in the weaner diets (linear, p<0.01; p = 0.05). High milk by-product treatment had higher feed cost per weight gain compared to non-milk by-products treatment (linear, p = 0.01). Conclusion: Supplementation of 10% to 5% milk by-products in weaning pig diet had results equivalent to the 30% to 15% milk treatment and 0% milk by-product supplementation in the diet had no negative influence on growth performance of finishing pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제30권8호
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• pp.1150-1159
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• 2017

Objective: This study was conducted to evaluate various wheat supplementation levels on growth performance, blood profiles, nutrient digestibility, and pork quality in growing-finishing pigs. Methods: A total of 120 growing pigs ($[Yorkshire{\times}Landrace]{\times}Duroc$), with an average $27.75{\pm}1.319kg$ body weight, were used in growth trial. Pigs were allotted into each treatment by body weight and sex in 4 replicates with 6 pigs per pen in a randomized complete block design. Fourphase feeding programs were used in this experiment. The treatments included the following: i) corn-soybean meal (SBM) - based diet (CON), ii) corn-SBM - based diet+15% of wheat (W15), iii) corn-SBM - based diet+30% of wheat (W30), iv) corn-SBM - based diet+45% of wheat (W45), and 5) corn-SBM-based diet+60% of wheat (W60). Results: There was no significant difference in growth performance among the dietary treatments. However, the gain-to-feed (G:F) ratio tended to increase (quadratic, p<0.08) when the pigs were fed a higher wheat diet during the finishing period. The digestibility of crude ash and fat tended to decrease as the wheat supplementation level increased (p<0.08). The proximate analysis of the longissimus muscle was not affected by the dietary level of wheat. The crude ash content in pork was decreased linearly as the wheat supplementation level increased (p = 0.05). There was no significant difference in the pH level, shear force, water holding capacity, and cooking loss of the pork. In pork and fat, $L^{\star}$, $a^{\star}$, and $b^{\star}$ values were not significantly different among dietary treatments. Conclusion: Wheat can be supplemented up to 60% in a growing-finishing pig without detrimental effects on growth and pork quality. The G:F ratio tended to improve in the finishing period by wheat inclusion.

• Journal of Biosystems Engineering
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• 제9권1호
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• pp.22-33
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• 1984

Husk separator is an indispensable equipment in rice milling plants. However, any basic research on the designing and operating criteria of the husk separator have rarely been conducted in Korea. According to the survey results reported recently, grain loss occurs in the process of rice husk separation at custom rice milling plants in Korea and the performance of husk separator has also not been identified. With this regard this study was conducted with a typical commercial husk separator to investigate the effect of the operational factors such as feed rate, blower speed and opening ratio on the velocity distribution in the air duct and the performance of the separator. The results are summerized as follows: 1. The average wind velocity in the primary air duct increased linearly with the blower rpm and the size of air inlet port in both cases of double type and single type operations. 2. The coefficient of variation in the horizontal wind velocities in the primary air duct was the minimum when the opening ratio was 0.22 ($0.052m^2$ of air inlet port) in both cases of single type and double type operations regardless of the blower speeds used in this test. The average wind velocity at the upper part of air duct was greater by 2-5 m/s than the velocity at the bottom part in double type operation. In case of single type operation, however, the average velocity in the middle part was greater than the upper or bottom part when the opening ratio was greater than 0.74. 3. The relationship between the overall effectiveness of separation(Ed for double type and Es for single type) and the average wind velocity (Va) in the primary air duct was expressed in the following quadratic functions. $$Ed=-190.84+106.18Va-10.052Va^2$$ ($r^2$ = 0.97782) $$Es=-223.76+106.23Va-9.1935Va^2$$ ($r^2$ = 0.97029) The average wind velocity required to obtain the overall effectiveness of separation more than 80% ranged from 4.04 m/sec to 5.84 m/sec in case of double type operation, and from 4.70 m/sec to 6.20 m/sec in case of single type. 4. An optimum wind velocity can be obtained with an increase in the blower speed or the size of air inlet port as presented in Figure 8. There was a tendency that the faster the blower speed, the narrower the control range of the air inlet port. 5. The feed rates (1850kg/hr and 2100kg/hr) adopted in this experiment did not bring about a significant difference in both the overall effectiveness of separation and the power consumption. 6. The energy consumption increased cubically with the blower speed but linearly with the size of the air inlet port. On the basis of the results described in items 1, 3, and 6, it would be more economic to adjust the size of the air inlet port larger with a relatively low blower speed than to adjust the size smaller with a relatively high speed.

• Journal of Ginseng Research
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• 제40권1호
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• pp.38-46
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• 2016

Background: Blind and excessive application of fertilizers was found during the cultivation of Panax notoginseng in fields, as well as increase in root rot disease incidence. Methods: Both "3414" application and orthogonal test designs were performed at Shilin county, Yunnan province, China, for NPK (nitrogen, phosphorus, and potassium) and mineral fertilizers, respectively. The data were used to construct the one-, two-, and three-factor quadratic regression models. The effect of fertilizer deficiency on root yield loss was also analyzed to confirm the result predicted by these models. A pot culture experiment was performed to observe the incidence rate of root rot disease and to obtain the best range in which the highest yield of root and saponins could be realized. Results: The best application strategy for NPK fertilizer was $0kg/667m^2$, $17.01kg/667m^2$, and $56.87kg/667m^2$, respectively, which can produce the highest root yield of 1,861.90 g (dried root of 100 plants). For mineral fertilizers, calcium and magnesium fertilizers had a significant and positive effect on root yield and the content of four active saponins, respectively. The severity of root rot disease increased with the increase in soil moisture. The best range of soil moisture varied from 0.56 FC (field capacity of water) to 0.59 FC, when the highest yield of root and saponins could be realized as well as the lower incidence rate of root disease. Conclusion: These results indicate that the amount of nitrogen fertilizer used in these fields is excessive and that of potassium fertilizer is deficient. Higher soil moisture is an important factor that increases the severity of the root rot disease.

• 한국가금학회지
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• 제39권3호
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• pp.167-175
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• 2012

본 실험은 대사 에너지와 조단백질 수준이 토종오리의 생산성 및 도체 특성에 미치는 영향을 연구하기 위해 수행되었다. 육성 전기는 토종오리 828수를 9개 처리에 공시하여 사용하였고, 육성 후기는 육성 전기를 거친 토종오리 중 720수를 9개 처리에 공시하여 사용하였다. 육성 전기의 실험 사료는 ME 3,000, 2,900 및 2,800 kcal/kg, CP 23, 22 및 21%이었으며, 육성 후기에는 ME 3,100, 3,000 및 2,900 kcal/kg, CP 19, 18 및 17%로 처리하여 사용하였다. 육성 전기 실험 결과는 CP 수준이 증가함에 따라 체중, 증체량 및 사료 요구율이 유의적으로 개선되었지만(Linear effect, P<0.01), ME 수준과 $ME{\times}CP$ interaction에 의한 유의차는 나타나지 않았다. 균일도는 ME, CP 수준과 $ME{\times}CP$ interaction 모두에서 유의차가 나타나지 않았다. 육성 후기 실험 결과는 체중, 섭취량, 증체량, 사료 요구율 및 균일도에서 유의한 차이가 관찰되지 않았으나, 도체율에서는 ME 3,000 kcal/kg에서 유의적으로 가장 높게 나타났으며(Quadratic effect, P<0.01), ME와 CP의 수준이 증가함에 따라 간의 상대적 중량이 유의적으로 각각 작아지는 결과(Linear effect, P<0.01)가 나타났다. 가슴육, 넓적다리 및 북채의 상대적 중량에서는 수준간 유의적인 차이는 나타나지 않았다. 토종오리 고기의 화학 및 물리적 특성인 육색, pH, 가열 감량 및 전단력가에서는 ME 및 CP 수준과 $ME{\times}CP$ interaction 모두에서 유의차가 나타나지 않았다.