• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1474-1479
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• 2012

Rotational smart lighting control system provides artificial light to plants on planting board by rotational lighting system. As the lighting system of existing plant factory has high cost problem due to the installation for many lighting equipments, the lighting system was developed to rotate less number of lighting equipments to reduce cost. In this paper, the illuminance, luminous flux and photosynthetic photon flux density(PPFD) that plants need to grow were calculated. And the light intensity at each measured location considering the rotational speed of blade were analyzed by the simulation and the experiment.

• Journal of Radiation Protection and Research
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• v.26 no.1
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• pp.7-12
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• 2001

Sintered LiF:Mg,Cu,Na,Si thermoluminescence (TL) pellets were developed for application in radiation dosimetry. In the present study, the TL dosimetric properties of LiF:Mg,Cu,Na,Si TL pellets have been investigated for emission spectrum, dose response, energy response, and fading characteristics. LiF:Mg,Cu,Na,Si TL pellets were made by using a sintering process, that is, pressing and heat treatment from TL powders. Photon irradiations for the experiments were carried out using X-ray beams and a $^{137}Cs$ gamma source at the Korea Atomic Energy Research Institute (KAERI). The average energies and the dose were in the range of 20-662 keV and $10^{-6}-10^{-2}\;Gy$, respectively. The glow curves were measured with a manual type TLD reader(System 310, Teledyne) at a constant nitrogen flux and a linear heating rate. For a constant heating rate of $5^{\circ}C\;s^{-1}$, the main dosimetric peak of glow curve appeared at $234^{\circ}C$, the activation energy was 2.34 eV and frequency factor was $1.00{\times}10^{23}$. TL emission spectrum is appeared at the blue region centered at 410 nm. A linearity of photon dose response was maintained up to 100 Gy. The photon energy responses relative to $^{137}Cs$ response were within ${\pm}20%$ at overall photon energy region. The fading of TL sensitivity of the pellets stored at the room temperature was not found for one year.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.333-338
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• 2021

This study determined the characteristics of LED illumination and photosynthetically active radiation flux density (PPFD) for LED lighting design in an indoor plant factory. This was done based on the light wavelength and PPFD intensity required for plant growth. It has been found that the wavelength and intensity are decreased according to the measuring distance, and green light has an important role in illumination characteristics, while blue light has an important role in the PPFD characteristics. Considering only the photosynthetic properties of plants, the effective order of photosynthesis was blue>red>white>green. When the measurement distance was 30 [cm], it was found that reduction levels of 60 [cm], 90 [cm], and 120 [cm] decreased to about 36 [%], 18 [%], and 10 [%], respectively. As a result of the characteristics of mixed light (red:blue=2:1, 3:1, 4:1) and the measurement distance, when the measured value at 30 [cm] is 100%, the measured value at 120 [cm] is 10-11 [%]. From the obtained results, an optimal structure was proposed for maximizing the light efficiency of an indoor greenhouse for future research.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.632-638
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• 2000

This paper represents the characteristics of evapotranspiration rate (EVTR) and graft-taking of watermelon grafted seedlings in a graft-taking enhancement system using fluorescent lamps as artificial lighting source. Four air temperature levels of 23, 25, 27 and 29C, three humidity levels of 85, 90 and 95%R.H. and two photosynthetic photon flux (PPF) levels of 30 and 50 ${\mu}$mol m$\^$-2/ S$\^$-1/ were provided to investigate the effects of air temperature, relative humidity and light intensity on EVTR and graft-taking of grafted seedlings. EVTR of grafted seedlings increased with increasing air temperature and the passage of time after grafting. Also EVTR increased with decreasing relative humidity. As relative humidity decreased and air temperature increased, vapor pressure deficit increased and thus EVTR increased. It is required to maintain a low level vapor pressure deficit for suppressing EVTR of grafted seedlings during first 1-2 days after grafting. Therefore, less EVTR at initial stage after grafting would be adequate for smooth joining of the scion and rootstock.

• Plant Biotechnology Reports
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• v.2 no.3
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• pp.207-212
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• 2008

Plantlets of Alocasia amazonica regenerated under a photon flux density (PFD) of 15 or $30{\mu}mol\;m^{-2}s^{-1}$ showed better growth and development than those grown under higher PFDs. While chlorophyll a and chlorophyll b decreased, the number of stomata increased with increasing PFD. Photoperiods also affected plantlet growth and stomatal development. Highest growth was observed for the short photoperiod (8/16 h) and for equinoctial (12/12 h) light and dark periods. Very few stomata developed in the leaves of plantlets grown under a short photoperiod (8/16 h) and the number of stomata increased with increasing light period. In conclusion, both light intensity and photoperiod independently affect growth of A. amazonica and development of stomata, depending on the intensity and duration of light treatment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.10
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• pp.14-22
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• 2011

The artificial lights to be introduced for the plant factories is requiring the artificial light resources with minimizing the energy consumption to reduce the greenhouse gases which is a major cause of global warming, and maximizing the efficiency in photosynthesis effect light-wave range, in which the plants can be greatly grown and developed, and having the signal light-wave range for forming the light types. the best growing and developing environment for the plants has recently realized with utilizing the LED(Lighting Emitting Diode) lamps, as a environment-friendly green lamps, which can elevating the light efficiency with using only the specific light wave range. In this study, to provide the necessary lights for the full artificial light type of the plant factory, the following research/study and experiments has been conducting. experiments of the spectrum for each light sources, and LED, The intensity of illumination, Irradiance, Photosynthesis Photon Flux Density.

• Nuclear Engineering and Technology
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• v.44 no.2
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• pp.161-176
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• 2012

McCARD is a Monte Carlo (MC) neutron-photon transport simulation code. It has been developed exclusively for the neutronics design of nuclear reactors and fuel systems. It is capable of performing the whole-core neutronics calculations, the reactor fuel burnup analysis, the few group diffusion theory constant generation, sensitivity and uncertainty (S/U) analysis, and uncertainty propagation analysis. It has some special features such as the anterior convergence diagnostics, real variance estimation, neutronics analysis with temperature feedback, $B_1$ theory-augmented few group constants generation, kinetics parameter generation and MC S/U analysis based on the use of adjoint flux. This paper describes the theoretical basis of these features and validation calculations for both neutronics benchmark problems and commercial PWR reactors in operation.

• Journal of Plant Biotechnology
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• v.41 no.3
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• pp.123-126
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• 2014

This paper is suitable for household plant factory by design and using both energy-saving LED and solar technology. Conventional household plant factory only depending on natural sunlight is sensitive for the change of external environment. Another a big problem of conventional common household plant factory is large power consumption. Recently interest in wellbeing food such as chemical-free is increased abruptly. To solve these two problems, this paper describes hybrid type of household plant. In particular, reducing the power photosynthesis photon flux density (PPFD) is kept uniform to enhance the growth of the plant. Ambient light sensor is adopted for the control of proper combination of sunlight and LED to keep PPFD constant.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.91.2-91.2
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• 2010

We present far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS, also called SPEAR) around perihelion between 8 and 15 May 2004. Several important emission lines, including S I (1425, 1474 ${\AA}$), C I (1561, 1657 ${\AA}$), CO (1087.9, 1340-1680 ${\AA}$) were detected. Especially, the spectral features of CO are its electronic transitions belongings to the A-X, C-X systems. We also obtained radial profile of S I, C I, H I $Ly{\beta}$ with line fitting from central coma. The production rate of several spectral lines calculated from observed FUV photon flux. FUV spectral images of S I, C I, H I $Ly{\beta}$ emission lines were obtained.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.125-130
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• 2002

식물공장의 인공광원으로 고압나트륨등, 메탈할라이드등 또는 형광등이 주로 사용되고 있다. 이 가운데 고압나트륨등과 메탈할라이드등의 경우 램프효율은 높으나 각각 청색광 또는 적색광이 부족하여 단독으로 사용되지 않고 병행해서 보광용으로 사용되므로 근접 조명을 위한 단독 광원으로 사용하기가 부적합하다. 형광등은 고압나트륨등과 같은 고휘도 방전등에 비해서 광속은 낮으나 광이용효율이 높기 때문에 조직배양묘의 근접 조명용 광원으로 사용되고 있다. (중략)