• 한국축산식품학회지
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• 제25권1호
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• pp.92-97
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• 2005

본 연구는 이유 전 자돈의 분변으로부터 분리·동정한 젖산균의 저온 배양에 따른 기초지식을 확보하고 이를 생균제 생산에 적용함으로써 제품내 젖산균의 생존력을 증대시키기 위해 실시하였다. 이유 전 자돈의 분변으로부터 분리·동정한 젖산균은 Lactobacillus acidophilus 1로 판명되었으며, 이를 L. acidophilus CT 01이라 명명하였다. 48시간 동안 저온 배양한 L. acidophilus CT 01은 배양온도가 22℃일 때 생장속도가 가장 느리게 나타났으나 배양 12시간 이후부터 생균수가 급격히 증가하기 시작하여 배양 36시간에 1.3×10/sup 9/ CFU/mL로 최대 생균수를 나타냈다. L. acidophilus CT 01을 저온 배양하여 12일간 4℃와 20℃에 저장한 결과 4℃에 저장한 경우 저온 배양한 처리구의 생존률이 90.30와 90.67%로 대조구(85.81%) 보다 높은 생존률을 나타냈으며(p<0.01), 20℃ 저장시 28℃에서 24시간 저온 배양한 처리구에서 가장 높은 생존률(82.67%)을 나타냈다(p<0.01). L. acidophilus CT 01의 냉동 내성은 저온 배양한 처리구가 대조구보다 생존률이 95.73와 97.34%로 높게 나타났다(p<0.01). L. acidophilus CT 01을 60℃에서 15분과 30분 동안 열처리하여 열저항성을 시험한 결과 22℃에서 저온 배양한 처리구의 생존률이 0.203와 0.108%로 대조구에 비해 높게 나타났다(p<0.01). L. acidophilus CT 01을 저온 배양하여 부형제에 30% 접종하고 50℃에서 12시간 건조하여 생존률을 조사한 결과 저온 배양한 처리구가 가장 높은 생존률을 나타냈다

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.322-326
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• 1989

This paper describes design procedure of suboptimal control to minimize a performance index which is represented as sum of square output error and the heat input power in arc welding process. Heat input and temperature of a fixed point on the surface of the material are concerned as input and output of the process, repectively. The suboptimal control law considered here in is a proportional plus integral type and is implemented by using only the output variables available from sensor which is also optimally located in a fixed point w.r.t. a moving weld touch.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.394-399
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• 2011

The effect of intermittent feeding on growth, feed utilization and body composition of subadult olive flounder fed extruded pellet (EP) in suboptimal temperature ($13.5{\pm}2.10^{\circ}C$) was determined. Two hundred twenty five subadult fish averaging 272 g were randomly distributed into fifteen of 300 L circular flow-through tanks (fifteen fish per tank). Five treatments with different days of feeding a week were prepared in triplicate: fish were hand-fed with EP to apparent satiation once a day, seven days a week (7DF), which was used as the control group or consecutive six, five, four and three days a week, for 12 weeks, referred to as 6DF, 5DF, 4DF and 3DF treatments, respectively. Weight gains and specific growth rates of fish in 6DF treatment were higher than those of fish in 7DF, 4DF and 3DF treatments, but not different from those of fish in 5DF treatment. Daily feed intake of fish in 6DF and 7DF treatments was higher than that of fish in 5DF, 4DF and 3DF treatments. Feed efficiency and protein efficiency ratio of fish were not different among treatments. There was no difference in the chemical composition of fish between treatments. Results of this study demonstrated that feeding five days per week could be recommended for subadult olive flounder fed extruded pellet in suboptimal temperature.

• 한국식품저장유통학회지
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• 제24권6호
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• pp.778-785
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• 2017

본 연구는 시중 유통되고 있는 새싹채소 재배용 적콜라비 종자에서 분리한 E. coli strain RC-4-D의 생장예측모델을 개발하기 위해 수행되었다. 각 온도조건(10, 15, 20, 25, $30^{\circ}C$) 별로 적콜라비 중 E. coli strain RC-4-D 밀도 변화를 조사하였고 Baranyi model을 1차 생장예측모델로 이용하였고 각 온도별로 최대생장률(${\mu}max$)과 $10^{\circ}C$를 제외한 유도기(LPD) 값을 도출하였다. E. coli strain RC-4-D의 최대생장률에 대한 2차 생장예측모델로써 suboptimal Ratkowsky square-root, suboptimal Huang square-root, suboptimal Arrhenius-type 세 종류의 모델을 비교하였다. 모델 적합성 검정 결과, suboptimal Huang square-root 모델이 정확도가 가장 높고 suboptimal Ratkowsky square-root 모델이 편차가 가장 적은 것으로 나타났다. 종합적으로, RMSE가 0.100, $A_f$가 1.255, $B_f$가 0.999인 suboptimal Ratkowsky square-root 모델이 온도의 영향을 설명하는 가장 적합한 2차 생장예측 모델인 것으로 나타났다. 본 연구에서 개발한 모델은 적콜라비 새싹채소 생산에 있어서 E. coli의 생장을 예측하고 미생물 위해성평가를 수행하는데 활용될 것으로 기대된다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권2호
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• pp.272-277
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• 2012

Compensatory growth of grower olive flounder (Paralichthys olivaceus) was determined at suboptimal temperature ($13.0{\pm}1.9^{\circ}C$). Fifteen fish averaging 201.1 g per tank were distributed into 18 of 300 L flow-through tanks. Six treatments were prepared in triplicate: fish were hand-fed with an extruded pellet to apparent satiation once a day for 16 weeks (16 WF); and the other five groups of fish were hand-fed for 15, 14, 13, 12 and 10 weeks after 1-, 2-, 3-, 4- and 6-week feed deprivation, referred to as 15 WF, 14 WF, 13 WF, 12 WF and 10 WF, respectively. A linear relationship between body weight of fish and feed deprivation was observed: Y (Body weight of fish) = -1.81X (Weeks of feed deprivation)+201.07, $R^2$ = 0.83. Weight gain of grower olive flounder in 15 WF, 14 WF, 13 WF and 12 WF treatments was comparable to that of fish in 16 WF treatment, but lower than that of fish in 10 WF treatment. Specific growth rate of fish in 15 WF treatment was higher than that of fish in 16 WF, 14 WF and 10 WF treatments. Feed consumption of fish was not affected by feeding regime. Feed and protein efficiency ratios of fish in 15 WF treatment were higher than those of fish in 13 WF, 12 WF and 10 WF treatments. Grower olive flounder could achieve full compensatory growth when fish were daily fed for 12 weeks after 4-week feed deprivation at suboptimal temperature.

• Journal of Communications and Networks
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• 제11권2호
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• pp.148-156
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• 2009

The fixed spectrum assignment policy in today's wireless networks leads to inefficient spectrum usage. Cognitive radio network is a new communication paradigm that enables the unlicensed users to opportunistically use the spatio-temporally unoccupied portions of the spectrum, and hence realizing a dynamic spectrum access (DSA) methodology. Interference temperature model proposed by Federal Communications Commission (FCC) permits the unlicensed users to utilize the licensed frequencies simultaneously with the primary users provided that they adhere to the interference temperature constraints. In this paper, we formulate two NP-hard optimal scheduling methods that meet the interference temperature constraints for cognitive radio networks. The first one maximizes the network throughput, whereas the second one minimizes the scheduling delay. Furthermore, we also propose suboptimal schedulers with linear complexity, referred to as maximum frequency selection (MFS) and probabilistic frequency selection (PFS). We simulate the throughput and delay performance of the optimal as well as the suboptimal schedulers for varying number of cognitive nodes, number of primary neighbors for each cognitive node, and interference temperature limits for the frequencies. We also evaluate the performance of our proposed schedulers under both additive white gaussian noise (AWGN) channels and Gilbert-Elliot fading channels.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.407-413
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• 2011

Effect of dietary protein and lipid levels on compensatory growth of juvenile olive flounder (Paralichthys olivaceus) was determined in suboptimal temperature ($13.4{\pm}1.42^{\circ}C$). Five hundred forty fish averaging 79.2 g were randomly distributed into 27 of 300 L flow-through tanks (20 fish/tank). Nine treatments were prepared in triplicate: fish were hand-fed with control (C) diet for 10 weeks (10WF-C); four fish groups were starved for 1 week and then fed with C, high protein (HP), high lipid (HL) and combined high protein and high lipid (HPL) diets for 9 weeks, referred to as 9WF-C, 9WF-HP, 9WF-HL, 9WF-HPL, respectively; and other four fish groups were starved for 2 weeks and then fed with C, HP, HL and HPL diets for 8 weeks, referred to as 8WF-C, 8WF-HP, 8WF-HL and 8WF-HPL, respectively. Weight gain and specific growth rate of fish in 9WF-HP, 9WF-HPL, 8WF-HP and 8WF-HPL treatments were higher than those of fish in 9WF-HL and 8WF-HL treatments. Feed efficiency of fish in 8WF-HP treatment was higher than that of fish in 9WF-C, 9WF-HL and 8WF-HL treatments. Protein efficiency ratio of fish in 10WF-C, 8WF-C, 8WF-HP and 8WF-HPL treatments was higher that that of fish in 9WF-HL and 8WF-HL treatments. Juvenile olive flounder subjected to 2-week feed deprivation could achieve full compensatory growth with dietary supplementation of protein or combined high protein and high lipid.

• 한국수산과학회지
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• 제42권3호
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• pp.262-267
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• 2009

Two 15-week feeding trials were conducted to investigate feeding rate and feeding frequency for growth of sub-adult flounder in suboptimal water temperature ($12^{\circ}C$). In the first experiment, duplicated groups of fish (initial mean weight of 279 g) were fed a extruded pellet once a day at the different feeding rates of 0.1, 0.15, 0.2, 0.3% body weight per day (BW/d), and satiation (0.32% BW/d). Weight gain and feed efficiency were increased significantly (P<0.05) with increase in feeding rates from 0.1 to 0.3% BW/d, but there were no significant differences in weight gain and feed efficiency of fish fed the diet between 0.3% BW/d and to satiation. Crude protein content of dorsal muscle of fish fed the 0.1% BW/d diet was significantly (P<0.05) lower than that of the other groups. In the second experiment, duplicated groups of fish (initial mean weight of 281 g) were fed to apparent satiation with a extruded pellet at three different feeding frequencies (one meal every two days, one meal a day and two meals a day). Weight gain, feed efficiency and condition factor of fish fed one meal every two days were significantly (P<0.05) lower than those of fish fed one meal and two meals a day, but there were no significant differences in weight gain, feed efficiency and condition factor of fish fed between one meal and two meals a day. Based on the results of this study, optimum feeding frequency is one meal a day with satiation feeding for growth and feed efficiency of sub-adult flounder (270-350 g) in suboptimal water temperature ($12^{\circ}C$).

• Fisheries and Aquatic Sciences
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• 제13권4호
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• pp.294-299
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• 2010

The effects of dietary nutrient composition on compensatory growth of grower olive flounder (Paralichthys olivaceus) under different feeding regimes at suboptimal temperature were determined. Four hundred five fish weighing 271.2 g were distributed into 27 300 L flow-through tanks (15 fish per tank). Nine treatments were prepared in triplicate: fish were hand-fed with control (C) diet for 12 weeks (12WF-C); four groups of fish were starved for 1 week and then fed C, high-protein (HP), high-lipid (HL), or combined high-protein and high-lipid (HPL) diets for 11 weeks; these groups are referred to as 11WF-C, 11WF-HP, 11WF-HL, and 11WF-HPL, respectively. Four other groups of fish were starved for 2 weeks and then fed C, HP, HL, and HPL diets for 10 weeks; these groups are referred to as 10WF-C, 10WF-HP, 10WF-HL, and 10WF-HPL, respectively. Weight gain and specific growth rate of fish from 12WF-C group were greater than those of fish from 11WF-C, 11WF-HP, 11WF-HL, 10WF-C, 10WFHP, and 10WF-HL groups, but not different from those of fish from 11WF-HPL and 10WF-HPL groups. Feed-efficiency ratio of fish from 12WF-C, 11WF-HP, 11WF-HPL, 10WF-HL, and 10WF-HPL groups was higher than that of fish in 11WF-C, 11WF-HL, 10WF-C, and 10WF-HP groups. The results of this study demonstrated that grower olive flounder subjected to 1- or 2-week feed deprivation were able to achieve full compensatory growth at suboptimal temperature only when fed HPL diet.

• 설비공학논문집
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• 제13권9호
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• pp.836-844
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• 2001

For the radiant floor heating system, the possibility of suboptimal prediction control was investigated by computer simulation and experiment. For this study, TRANSYS program was used and an experimental facility consisting of two rooms (3$\times$4.4$\times$2.8m) was built. The facility enabled simultaneous comparison of two different control strategies which implemented in a separate room. Results showed that outdoor air temperature prediction control was superior to the conventional outdoor air temperature compensation control for radiant floor heating system. However, more research for fine prediction of outside air temperature was required in the future.