• Journal of Biosystems Engineering
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• 제15권4호
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• pp.328-338
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• 1990

The objective of this study was to develop automatic systems of nutrient solution management for optimal nutrient solution environment and labor saving in water culture which enables factory crop production. In this study, an automatic control system and its driving program are developed to prepare, supply, and recover nutrient solution and to keep the optimal solution concentration level using microcomputers. Based on this study, the following conclusions are obtained: 1. The concentration measured by the system using oscillating circuit designed and built in this study, gave good agreements with the actual nutrient solution. 2. In water culture, the period of 12 hours for measuring concentration, pH, and temperature of the nutrient solution was optimum. Addition of control solution due to the decrease of the nutrient solution concentration is required in every 3 to 5 days. 3. It is estimated that the period of the whole solution change is 15 days, however, further research is needed to assure it. In addition, this period must be shortened in the future. 4. Both the hardware and software of the developed optimal nutrient solution control system in the water culture are working very well, however, it is necessary to develop a more economical one-chip micro controller to substitute for the microcomputer.

• 대한본초학회지
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• 제20권2호
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• pp.1-6
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• 2005

Objectives : The purpose of this study is to investigate genetic toxicity of Cervi pantotrichum Cornu herbal acupuncture solution(CPCHA). Methods : In this study, a series of investigation have been carried out to analyze the effects of Cervi pantotrichum Cornu herball acupuncture solution(CPCHA) on colony forming ability of NIH3T3cells, Hela cells and adrenorectal coloncell for genetic toxicity test. Results and Conclusions : From the above results, it is suggested that Cervi pantotrichum Cornu herball acupuncture solution(CPCHA) was limited 0.5-10ug/ml by test. Cervi pantotrichum Cornu herball acupuncture solution(CPCHA) did not exert the protective role to the genetic toxicity in kinds of cell lines used in this study. From these results, Cervi pantotrichum Cornu herbal aqua-acupuncture solution needs further study to prove it's function in cell culture system.

• 한국농공학회지
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• 제41권2호
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• pp.37-43
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• 1999

This study was conducted to develop the simple and convenient irrigation control model which can maintain the appropriate rates of irrigation and drainage of nutrient solution according to the enviornmental conditions and growth stages in soilless culture of cucumber. In order to obtain fundamental data for development of the model, investigation of the actual state of soilless culture practices was carried out. Most irrigatioin systems of soillness culture were controlled by the time colock. Evapotranspiration of cucumber in soilness culture was investigated and correlations with environmental conditions were analyzed , and its estimating model was developed. In order to develop the irrigation system which can control the amount of nutrient solution applied according to seasons, weather conditions, and growth stages, a irrigation clock control was developed. Applicability of the model was tested by simulation. Drainage rates of nutrient solution controlled by conventional time clock, integrated solar radiation, and the developed model were 61% , 20%, and 32% , respectively in cucumber perlite culture.

• 원예과학기술지
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• 제31권4호
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• pp.423-428
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• 2013

Although closed soilless culture is useful for saving water and fertilizers with minimizing environmental pollution, adequate management of nutrient solutions is still not stabilized in greenhouse cultivation. In order to investigate the problems occurred in closed soilless culture of Paprika (Capsicum annuum L., cv. Fiesta), we compared ion balance, fruit yield, and the water and fertilizer use efficiencies in the closed system with those in the open system. The plants were grown in rockwool culture with a nutrient solution of EC $2.5dS{\cdot}m^{-1}$. After 4 weeks of treatment, individual ratio of $NO{_3}^-$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ to total ion concentrations ($meq{\cdot}L^{-1}$) decreased from the initial value, especially the biggest decrement was observed in $K^+$, and on the other hand, $SO{_4}^{2-}$, $Cl^-$, and $Na^+$ were accumulated in the closed system. Yields after four-time harvests were 19% higher in the open system than in the closed system. Total volume of water used per unit area ($m^2$) in the open system was 20% higher, but the total water use per fruit was not significantly different between the two systems, while t total fertilizer use per fruit was 78% higher in the closed system. Amount of marketable fruits was not significantly different between the two systems. We concluded that the increase in $K^+$ supply and the replenishment of recycled nutrient solution every four weeks were required for preventing the imbalance or depletion of nutrients in the close soilless culture of paprika plants to get more balanced nutrient composition during whole cultivation period.

• 한국시스템다이내믹스연구
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• 제7권1호
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• pp.173-212
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• 2006

This paper attempts to provide a more complete acknowledging of Hallyu(Korean Wave), using systems thinking. The central concept is understanding how all the objects of Hallyu(Korean Wave) in a culture system interact with one another. What it attempts to do is understand the feedback loop of Hallyu(Korean Wave) with other country culture, and thus understand the behavior of mass culture agent it make produce. This works is for public management and policy in culture industry and leading culture itself. And alternative policies that alleviate the problem, and implements this solution at Hallyu(Korean Wave) continuance.

• 농업생명과학연구
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• 제44권6호
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• pp.23-26
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• 2010

펄라이트자루를 사용한 수경재배에서 급액관리방식의 일종인 배액전극제어법에 필요한 배액 이동매개체를 선발하기 위해서 시판되고 있는 친수성 매트 중에서 극세사, 융, 면 등의 배양액 흡수속도를 분석했다. 또한, 선택된 매트가 배액전극제어법을 적용하였을 때에도 높은 흡수속도를 갖는지 알아보기 위해 연구를 수행하였다. 실험결과 면이 가장 수분보유력이 뛰어났으며, 배액전극제어법을 적용했을 때에도 가장 적합한 것으로 나타났다.

• Journal of applied mathematics & informatics
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• 제19권1_2호
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• pp.203-214
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• 2005

In this study the optimal control of fed-batch glycerol fermentation is investigated based on an impulsive dynamical system. Considering the sudden increase of the glycerol and alkali in fed-batch culture of biodissimilation of glycerol to 1,3-propanediol, this paper proposes a non-linear impulsive system of fed-batch culture. The existence, uniqueness and regularity properties of piecewise solution for the system are proved. In view of the controllability of volumes of glycerol added to the reactor instantaneously, the paper constructs an optimal control model based on the nonlinear impulsive system and the existence of the optimal control is obtained. The control variables here are the moments and the sizes of jumps in the states at the discrete instants and the objective is to maximize the productivity of 1,3-propanediol over one cycle.

• 생물환경조절학회지
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• 제6권3호
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• pp.198-204
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• 1997

감자 소괴동 산을 위해 적합한 양담재배방식을 구명코자 분무경, NFT, perlite 및 scoria 배지비을 이용하여 '대지' 품종을 공시하고 생육과 소엽도의 연성 및 준양에 미치는 영향을 조사한 결과는 다음과 같다. 1. 분무병 방식이 NFT 방식이나 Perlite 및 scoria 배지경에 비해 정식 후 40일과 60일의 지상부 생조이 좋았고, 정식후 90일에는 동윤이 65.4cm, 주당자육가 7.3개로서 가장 많았으며, scoria 배지경은 기윤이 49.5cm, 도상기육 3.2개로서 가장 적었다. 2. 포지장은 분무비에서 30.4cm로 가장 길었고, 주당각지육는 NFT 방식에서 10.5개로 많았다. 3. 정식 후 90일에 주당 괴경수는 분무경에서 67.1개, NFT 62.5개, Perlite 배지경 20.1개, scoria 배지경 18.0개였다. 4. 3g 이상의 괴대 크기 분포는 분무경 72.7％, NFT 62.6％, perlite 배지비 84.1％, scoria 배지경 83.3％로 고협배지경이 높은 분포를 보였으나 주당 괴동수가 적기 때문에 총수양 은 적었다. 5. Perlite 배지경에서 황산된 소괴경은 피일발이이 적고 표피가 매끄러워서 보질의 괴대이 생산되었다.

• 원예과학기술지
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• 제16권1호
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• pp.25-26
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• 1998

본 연구는 정량펌프를 이용한 정확한 증산량 추정 시스템의 구축 및 측정된 증산량과 환경요인과의 관계를 분석하는 데 있다. 정량펌프에 의한 양액공급 및 증산량 추정 시스템은 매우 안정적인 특성을 나타냈으며, 증산량 추정을 위하여 재배 시스템에 설치한 정량펌프의 공급시간과 투입량과의 관계는 직선관계를 나타냈다. NFT 및 고형배지 시스템에서의 적산일사량과 증산량을 실측한 결과 증산량은 일사량에 직접적인 영향을 받고 있었으며, NFT는 상관계수 0.98. 고형배지는 상관계수 0.92의 높은 상관관계를 나타내었다. 따라서 정량펌프에 의한 증산량 추정은 양액급액 제어에 효율적인 방법이며, 이러한 방법을 사용하여 적산일사량에 의한 관수량 조절 및 비료투입량의 결정에 적용이 가능하다. 따라서, 측정된 적산일사량에 의하여 증산량 추정이 가능하기 때문에, 정량펌프에 의하여 필요 관수량을 정확한 공급할 수 있다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1411-1414
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• 2008

It is reported that mechanical stimulation takes a role in improving cell growth in skeletal system. And various research groups have showed that developed bioreactor to stimulate cell-seeded and threedimensional scaffold. In this study, we designed a custom-made bioreactor capable of applying controlled compression to cell-seeded agarose gel. This device consisted of a circulation system and compression system. In circular system, culture chamber was sealed for prohibiting contamination and media solution was circulated by pump. In compression system, mechanical stimuli were controlled by LabVIEW software and mechanical transfer system. Cell-encapsulated agarose gels were cultured for up to 7 days. There were significant differences between the number of cells grown in dynamic cell culture and in static cell culture from 3 days to 7 days.