• 한국수산과학회지
• /
• 제44권4호
• /
• pp.372-377
• /
• 2011

The feeding habits of the redbanded searobin Lepidotrigla guentheri were studied using 186 specimens collected from September to November, 2006, in the coastal waters off Gori, Korea. The sizes of L. guentheri ranged from 7.1 to 16.7 cm total length(TL). L. guentheri is a bottom-feeding carnivore that consumes mainly shrimp, especially Leptochela sydniensis, amphipods, and crabs. Its diet also includes small quantities of stomatopods, mysids, cumaceans, euphausiids, polychaetes, and copepods. Our feeding-strategy graphical method reveled that L. guentheri is a specialized feeder, with a narrow niche width. L. guentheri mainly consumed shrimp of all size classes and did not show significant ontogenetic changes in feeding habits. Smaller individuals(7-11 cm TL) secondly consumed amphipods, with the portion of amphipods in the total diet decreasing as body size increased. Prey size increased significantly as the fish grew in size.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
• /
• pp.250-253
• /
• 2000

We researched effects of growth on initial inoculum size, liquid volume, and medium feeding rate etc. Cell suspension inoculated at low cell concentrations showed a typical growth reduction, whereas root cultures showed an improvement in growth. In this paper, Hairy roots showed high growth rate at 0.4 % inoculum size and 100 mL liquid volume in 250 mL flask cultures.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2012년도 전력전자학술대회 논문집
• /
• pp.258-259
• /
• 2012

This paper proposes a new control strategy to eliminate the harmonic components of stator current for stand-alone DFIG system feeding non-linear loads. In this method, the LSC operates as an active filter which is controlled by employing a proportional-integral and a resonant controller. And also, the stator current is used as the feedback signal for the compensator instead of the load current, so that the additional current sensor at the load side can be removed. The experiment is verified to validate the effectiveness of the proposed compensating method.

• 한국산학기술학회논문지
• /
• 제16권2호
• /
• pp.1240-1252
• /
• 2015

본 연구는 요양시설 치매노인을 대상으로 식사행동장애 실태와 영향요인을 규명하기 위한 서술적 조사연구이다. 연구대상은 일 지역 3개 요양시설에 거주하는 치매노인 158명이었으며, 연구기간은 2014년 8월18일부터 9월12일까지였으며, 식사행동장애, 신체기능(K-ADL) 및 인지기능(MMSE-K)을 측정하였다. 수집된 자료는 t-test, ANOVA, 상관관계, 회귀분석으로 검정하였다. 식사행동장애 정도는 전체 평균이 $0.62{\pm}0.43$점(0-2점 범위)이었고, 식사 중 주의 깊은 감독이 필요하다가 가장 빈도가 높은 식사행동장애였다. 회귀분석결과 신체기능(${\beta}=.312$), 인지기능(${\beta}=-.172$) 순으로 식사행동장애에 영향을 미쳤고, 이들 변수의 설명력은 20.0%였다. 이러한 연구결과는 요양시설 치매노인의 식사행동장애를 돕기 위한 식사행동단계별 대처전략 개발, 시설 돌봄 제공자의 교육프로그램 개발 연구의 필요성을 제시한다.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제11권sup1호
• /
• pp.143-148
• /
• 2008

조사에 의하면 정상적으로 발달하는 유아 아동의 25%~40%정도가 발달의 어떤 단계에서 섭식에 문제를 보일 수 있다고 한다. 많은 경우에 특별한 전문가적 도움없이 발달 과정을 거치면서 문제가 저절로 해결되는 경우도 있으나, 그 중 일부는 성장과 발달 및 가족 생활에 큰 스트레스가 될 정도의 섭식문제를 보이며 심한 경우 그 문제가 오랫동안 지속될 수 있다. 섭식문제는 섭식 그 자체의 문제뿐 아니라 음식거부를 위한 다양한 문제행동을 수반하게 되는데, 기존의 연구 결과는 행동수정의 한 형태인 응용행동분석이 가장 효과적인 치료법이라 보고한다. 문제가 극심한 경우엔 다학제적 팀으로 구성된 전문적인 치료가 필수적이나, 중경도의 문제는 그 종류에 따라서 부모교육을 통해 해결될 수 있기도 하다. 섭식 치료에는 문제를 규명하는 평가 절차가 가장 먼저 선행되어야 하며, 이를 근간으로한 치료책을 개발하고 적용할 때 가장 효과적인 결과를 얻을 수 있다. 치료는 보이는 문제 유형에 따라 달라져야 하는데, 유아 아동들이 가장 빈번하게 보이는 섭식문제 종류와 그에 적절한 구체적인 방법들을 제시하였다. 마지막으로, 부모교육을 통해 유아 아동의 섭식문제를 다룰 때 전문가들이 고려해 주어야 하는 사항들에 대해서 열거해 보았다.

• Journal of Microbiology and Biotechnology
• /
• 제32권7호
• /
• pp.902-910
• /
• 2022

The ginsenoside compound K (C-K) is widely used in traditional medicines, nutritional supplements, and cosmetics owing to its diverse pharmacological activities. Although many studies on C-K production have been conducted, fermentation is reported to produce C-K with low concentration and productivity. In the present study, addition of an inducer and optimization of the carbon and nitrogen sources in the medium were performed using response surface methodology to increase the C-K production via fermentation by Aspergillus tubingensis, a generally recognized as safe fungus. The optimized inducer and carbon and nitrogen sources were 2 g/l rice straw, 10 g/l sucrose, and 10 g/l soy protein concentrate, respectively, and they resulted in a 3.1-fold increase in the concentration and productivity of C-K (0.22 g/l and 1.52 mg/l/h, respectively) compared to those used before optimization without inducer (0.071 g/l and 0.49 mg/l/h, respectively). The feeding methods of American ginseng extract (AGE), including feeding timing, feeding concentration, and feeding frequency, were also optimized. Under the optimized conditions, A. tubingensis produced 3.96 mM (2.47 g/l) C-K at 144 h by feeding two times with 8 g/l AGE at 48 and 60 h, with a productivity of 17.1 mg/l/h. The concentration and productivity of C-K after optimization of feeding methods were 11-fold higher than those before the optimization (0.22 g/l and 1.52 mg/l/h, respectively). Thus, the optimization for the feeding methods of ginseng extract is an efficient strategy to increase C-K production. To our knowledge, this is the highest reported C-K concentration and productivity via fermentation reported so far.

• 한국수산과학회지
• /
• 제45권1호
• /
• pp.76-81
• /
• 2012

The feeding habits of daggertooth pike conger Muraenesox cinereus were studied using 380 specimens collected in the coastal waters off Goseong, Korea, from June to September, 2011. The M. cinereus ranged from 10.0-23.7 cm in anal length (AL). M. cinereus is a piscivore that consumes mainly fish. Engraulis japonicus was the preferred prey, but its diet also included small numbers of crabs, shrimps, cephalopods, and bivalves. The feeding strategy graphical method revealed that M. cinereus is a specialized feeder with a narrow niche width. All size classes of M. cinereus consumed fish and M. cinereus did not show significant ontogenetic changes in feeding habits. The diet overlap index between size classes was >0.96, indicating high diet similarities. The prey size increased significantly with M. cinereus size.

• Journal of Electrical Engineering and Technology
• /
• 제10권3호
• /
• pp.1370-1376
• /
• 2015

Generally, an autotransformer(AT) feeding system consists of double tracks, up and down, with the trolley wire and feeder wire of the up and down tracks connected in the sectioning post(SP). Consequently, load current or fault current flows on two tracks based on catenary impedance characteristics, making it difficult to estimate catenary impedance accurately. This paper presents a technique for the estimation of catenary impedance using boosting current compensation based on the current division characteristics of an AT feeding system to improve the operation performance of impedance relay. To verify the technique, we model an AT feeding system through a power analysis program (PSCAD/EMTDC) and simulate various operation and fault conditions. Through the simulation, we confirmed that the proposed technique has estimated catenary impedance with a similar degree of accuracy to the actual catenary impedance

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제5권5호
• /
• pp.340-344
• /
• 2000

Microbial oxidation of D-sorbitol to L-sorbose by Acetobacter suboxydans is of commercial importance since it is the only biochemical process in vitamin C synthesis. The main bottleneck in the batch oxidation of sorbitol to sorbose is that the process is severely inhibited by sorbitol. Suitable fed-batch fermentation designs can eliminate the inherent substrate inhibition and improve sorbose productivity. Fed-batch sorbose fermentations were conducted by using two nutrient feeding strategies. For fed-batch fermentation with pulse feeding, highly concentrated sorbitor (600g/L) along with other nutrients were fed intermittently in four pulses of 0.5 liter in response to the increased DO signal. The fed-batch fermentation was over in 24h with a sorbose productivity of 13.40g/L/h and a final sorbose concentration of 320.48g/L. On the other hand, in fed-batch fermentation with multiple feeds, two pulse feeds of 0.5 liter nutrient medium containing 600g/L sorbitol was followed by the addition of 1.5 liter nutrient medium containing 600g/L sorbitol at a constant feed rate of 0.36L/h till the full working capacity of the reactor. The fermentation was completed in 24h with an enhanced sorbose productivity of 15.09g/L/h and a sorbose concentration of 332.60g/L. The sorbose concentration and productivity obtained by multiple feeding of nutrients was found to be higher than that obtained by pulse feeding and was therefore a better strategy for fed-batch sorbose fermentation.

• Journal of Microbiology and Biotechnology
• /
• 제24권1호
• /
• pp.59-69
• /
• 2014

One of the major challenges in metabolic engineering for enhanced synthesis of value-added chemicals is to design and develop new strains that can be translated into well-controlled fermentation processes using bioreactors. The aim of this study was to assess the influence of various fed-batch strategies in the performance of metabolically engineered Pseudomonas putida strains, ${\Delta}gcd$ and ${\Delta}gcd-pgl$, for improving production of medium-chain-length polyhydroxyalkanoates (mcl-PHAs) using glucose as the only carbon source. First we developed a fed-batch process that comprised an initial phase of biomass accumulation based on an exponential feeding carbon-limited strategy. For the mcl-PHA accumulation stage, three induction techniques were tested under nitrogen limitation. The substrate-pulse feeding was more efficient than the constant-feeding approach to promote the accumulation of the desirable product. Nonetheless, the most efficient approach for maximum PHA synthesis was the application of a dissolved-oxygen-stat feeding strategy (DO-stat), where P. putida ${\Delta}gcd$ mutant strain showed a final PHA content and specific PHA productivity of 67% and $0.83g{\cdot}l^{-1}{\cdot}h^{-1}$, respectively. To our knowledge, this mcl-PHA titer is the highest value that has been ever reported using glucose as the sole carbon and energy source. Our results also highlighted the effect of different fed-batch strategies upon the extent of realization of the intended metabolic modification of the mutant strains.