• 분석과학
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• 제24권3호
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• pp.159-167
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• 2011

식물 체중에 포함되어 있는 항산화제로서 주목받고 있는 게르마늄과 셀레늄의 극미량 분석에 있어서의 재현성 있는 분석방법을 제시하고자 수소화물생성장치와 유도결합플라스마질량분석기를 이용하여 분석하였다. 유도결합플라스마질량분석기에 일반적으로 사용되는 torch 대신 에너지 밀도를 높여 이온 간섭, 분자이온 생성 등의 간섭현상을 줄일 수 있는 mini torch를 사용하여 산 종류와 농도의 영향, 수소화물의 생성을 위한 환원조건, 시료 전처리 방법의 차이 등 다양한 조건하에서 상추 중의 게르마늄과 셀레늄을 분석하였다. 분석의 정확성을 평가하기 위하여 회수율 검증과 셀레늄의 표준시료인 SRM-1547, 1570a을 분석하여 기준 값과 비교함으로서 분석의 정확성을 평가하여 다음과 같은 결론을 얻었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.296-296
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• 2015

The aim of this paper is to numerically explore the feasibility of designing a Mini-Hydro turbine. The interest for this kind of horizontal axis turbine relies on its versatility. For instance, in the field of renewable energy, this kind of turbine may be considered for different applications, such as: tidal power, run-of-the-river hydroelectricity, wave energy conversion. It is fundamental to improve the turbine performance and to decrease the equipment costs for achievement of "environmental friendly" solutions and maximization of the "cost-advantage". In the present work, the commercial CFD code ANSYS is used to perform 3D simulations, solving the incompressible Unsteady Reynolds-Averaged Navier-Stokes (U-RANS) equations discretized by means of a finite volume approach. The implicit segregated version of the solver is employed. The pressure-velocity coupling is achieved by means of the SIMPLE algorithm. The convective terms are discretized using a second order accurate upwind scheme, and pressure and viscous terms are discretized by a second-order-accurate centered scheme. A second order implicit time formulation is also used. Turbulence closure is provided by the realizable k - turbulence model. In this study, a mini hydro turbine (3kW) has been considered for utilization of horizontal axis impeller. The turbine performance and flow behavior have been evaluated by means of numerical simulations. Moreover, the performance of the impeller varied in the pressure distribution, torque, rotational speed and power generated by the different number of blades and angles. The model has been validated, comparing numerical results with available experimental data.

• 한국기계가공학회지
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• 제20권7호
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• pp.89-96
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• 2021

In this study, a mini hydro cyclone was designed and manufactured to achieve an inlet flow rate of 2 L/min in the experiment, which was conducted using alumina powder with a specific gravity of 3.97. This hydro cyclone was studied for using in steam and water analysis system (SWAS) of thermal power plant and was manufactured by 3D printing. Numerical analysis was performed with Solidworks Flow Simulation, utilizing the reynolds stress method (RSM) of fluid multiphase flow analysis models. Experimental and numerical analysis were performed under the three conditions of inlet velocity 2.0, 4.0, and 6.0 m/s. The separation efficiency was over 80% at all inlet velocity conditions. At the inlet velocity 4m/s, the separation efficiency was the best, and it was confirmed that the efficiency was more than 90%.

• 한국작물학회지
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• 제46권2호
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• pp.121-124
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• 2001

Potato (Solanum tuberosum L.) tubers of 10, 20, 30, 40, and 50 g were planted in plug trays with vermiculite-based root medium on 10 August 2000 and grown for 15 days in a glasshouse to determine the effects of mini-tuber size on plug seedling growth and field performance of plug seedlings. For a control, common potato tubers weighing 50 g were also planted. As size of seed tubers planted increased from 10 to 50 g, seedling height decreased from 24.6 to 20.0cm while shoot number per seedling increased from 2.0 to 3.5, main stem diameter from 4.3 to 6.1mm, and fresh weight of root + top from 9.3 to 19.4 g/seedling. At 90 days after transplanting plug seedlings, the total number of tubers per plant increased from 3.62 to 4.72, average tuber weight from 62.9 to 72.8g, and total tuber yield 20.5 to 23.6 t/ha with increase in seed tuber size. Plug seedlings raised from 50g tubers produced 22% more tubers per plant and had 21 % higher＞80g tuber yield than the directly planted potatoes.

• Journal of Photoscience
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• 제10권1호
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• pp.157-164
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• 2003

Light exerts two primary roles in plant growth and development. Plants acquire all biochemical energy required for growth and propagation solely from light energy via photosynthesis. In addition, light serves as a medium through which plants recognize environmental fluctuations, such as photoperiod and presence of neighboring animals and plants. Plants therefore constantly monitor the direction, intensity, duration, and wavelength of environmental light and integrate these light signals into the intrinsic regulatory programs to achieve an optimized growth in a given light condition. Although light regulates all aspects of plant growth and developmental aspects, the molecular mechanisms and signaling cascades involved have not been well established until recently. However, recent advances in genetic tools and plant transformation techniques greatly facilitated the elucidation of molecular events in plant photomorphogenesis. This mini-review summarizes the gist of recent findings in deetiolation and suppression of shade avoidance response as classic examples of the phytochrome-mediated photomorphogenesis.

• 한국포장학회지
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• 제23권1호
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• pp.47-53
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• 2017

최근 화훼 산업의 활성화를 위하여 정부 주도의 캠페인, 꽃 문화 확산 운동 등 화훼 소비 증대를 위한 활동들이 꾸준히 진행되고 있다. 절화류 상품은 MA 포장, 기능성 포장 개발 등 다양한 방법을 통하여 상품의 품질 유지를 위한 연구가 진행되고 있으나, 국내 분화류 제품의 경우 품질 개선 및 포장 디자인 등에 대한 연구가 여전히 미비한 실정이다. 또한 소형 분화류의 온라인 마켓 유통량이 점차 증가되고 있음에 따라, 산지에서 소매점, 소비자에게 이르기까지 제품의 품질 유지를 위한 다양한 구조 형태의 포장 개발이 요구되고 있다. 본 조사 연구는 소형 분화류 제품에 대한 소비자의 요구에 적합한 포장을 고려하기 위하여 기존 포장을 개선하는 목적으로 포장 소재 및 형태, 투명도, 편리성, 및 기타 포장 선호도 등에 대한 조사를 실시하였다. 결과로 플라스틱 포장 소재, 분리형 포장, 투명 포장 그리고 상품의 안정성 및 품질 유지를 위한 포장을 선호하는 것으로 파악되었다. 따라서 국내 소비자의 소형 분화류 상품 선호도 조사 연구를 바탕으로 향후 다양한 분화류 제품 및 제품 크기에 따른 상품화 가능성, 가격 변화 요인 등을 고려한 연구가 추가적으로 진행되어야 될 것으로 판단된다.

• Advances in Energy Research
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• 제2권2호
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• pp.85-95
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• 2014

Small Hydro-Power (SHP) is an environmental friendly technology. Usually hydro power generation projects are viewed as constructing large dams and reservoirs but available new research and engineering techniques have helped hydro power generation without large dams and without large reservoirs. In India, there are several water installations, irrigation dams, canals, streams or running rivers not tapped to generate power. In these cases the existing system and facilities can help in generating power with less investment and time. This area is yet unexplored. Harnessing a stream for hydroelectric power is a major undertaking for the energy crises and the global issues to go green. In this technical note a potential site for mini hydro power plant nearby Shoolini University is identified and examined for the economic feasibility.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 춘계학술대회논문집
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• pp.249-252
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• 1997

Mini-mill process which is one of the new steel making process to be able to produce the hot rolled strip by thin slab caster, was completed in the kwangyang steel work. The new process was constructed liquid core deduction, tandem reduction unit, induction heater, coil box and finishing mill to be varied width. Therefore, in oder to make sure of target strip width, analysis of actual plant data was done to fine out amount of width deviation. Finally, the predication system of width in the mini-mill process was developed to included temperature caculation model.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.67-67
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• 2000

In this paper, a hybrid type fuzzy controller is proposed to maintain molten steel level stable and reliable manner in high speed continuous casting regardless of various disturbances such as casting speed change, tundish weight variation, 치ogging/undoning of SEN(Submerged Entry Nozzle), periodic bulgings, etc. To accomplish this purpose, hardware filter and software filer are carefully designed to eliminate high frequency noise and to smooth input signals from harsh environments. In order to minimize the molten steel level variations from various disturbances the controller uses hybrid type control term: fuzzy logic term, proportional term, differential term and nonlinear feedback compensation tenn. The proposed controller is applied tn commercial mini-mill plant and shows considerable improvement in minimizing the molten steel variation.

• 생물환경조절학회지
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• 제8권1호
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• pp.30-35
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• 1999

감자 양액재배시 소괴경의 생산효율을 높이기 위해 감자 유식물체를 정식후 35일에 10시간 동안 배양액 pH를 3.0, 4.0, 5.0과 6.5로 각각 조절하였을 때 생육상황과 소괴경 수량을 조사한 결과, 소괴경 형성은 pH 3.0 처리구에서 빨랐으며 처리후 20일까지는 유의성있는 증가를 보였다. 배양액 pH가 낮을수록 복지수가 증가되어 괴경수가 많았으며 괴경 건물율도 높았고 정식후 90일째 소괴경 수량은 pH 3.0처리에서 72.1개, pH 4.0에서 69.8개, pH 5.0에서 65.2개, pH 6.5에서 60.3개였다. 3g이상크기의 소괴경의 분포비율은 pH 3.0에서57.9%로 가장 높았으며 pH 5.0과 6.5에서 50.8%로서 가장 낮았다.