• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.161-165
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• 2000

Spectroradiometric light transmittance from 300 to 1,100nm in the greenhouse covered with the CEM BIO polyethylene film was greater than that in the greenhouse covered with polyethylene film (control). As a whole, solar radiation transmittance into greenhouse was a half level, due to shades caused by double layer covering, frame and equipment. Net radiation energy emitted throughout surface of the greenhouse covered with CEM BIO polyethylene film was 5,424.5W.m$^{-2}$ , which was lower by 2.9% as compared to that of the greenhouse covered with polyethylene film. Photosynthetically active radiation from 400 to 700nm of the greenhouse covered with CEM BIO polyethylene film was 3,861.2W.m$^{-2}$ , which was higher by 3.8% as compared to hat of the greenhouse covered with polyethylene film. Accumulated minimum air temperature from Oct. 7, 1997 to Oct. 16, 1997 of the greenhouse covered with CEM BIO polyethylene film was 100.5$^{\circ}C$, which was higher by 2.5$^{\circ}C$ as compared to that of the greenhouse covered with polyethylene film. As results, height, stem diameter, leaf count, leaf area, fresh weight and dry weight of green pepper plants and canopy production structure measured at 30 days after transplanting were enhanced. Mean fruit weight n the greenhouse covered with CEM BIO polyethylene film was 11.28 g and 1.25 g greater as compared to that in the greenhouse covered with polyethylene film, due to increased fruit diameter and flesh thickness. Percent marketable fruits produced in the greenhouse covered with CEM BIO polyethylene film were 96.1%, and was greater by 2.7% thant that of the greenhouse covered with polyethylnee film due to decreased infection, sterility, severe curve and twisted fruits. The green pepper yield of the greenhouse covered with CEM BIO polyethylene film from Nov. 19, 1997 to Feb. 3, 1998 was greater by 974 kg per hectare than that of the greenhouse covered with polyethylene film, but the total fruit had no difference.

• Korean Journal of Heritage: History & Science
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• v.44 no.1
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• pp.72-105
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• 2011

This study explores the value of the Dicentra spectabilis community as a nature reserve in provincial forests at San 1-2, Daea-ri, Dongsang-myeon, Wanju-gun, Jellabuk-do, also known as Gamakgol, while defining the appropriateness of its living environment and eventually providing basic information to protect this area. For these reasons, we investigated 'morphological and biological features of Dicentra spectabilis' and the 'present situation and problems of designing a herbaceous nature reserve in Korea.' Furthermore, we researched and analyzed the solar, soil and vegetation condition here through a field study in order to comprehend its nature reserve value. The result is as follows. According to the analytic result for information on the domestic wild Dicentra spectabilis community, it is evenly spread throughout mountainous areas, and there is one particularly outstanding in size in Wanju Gamakgol. Upon the findings from literature and the field study about its dispersion, Gamakgol has been discovered as an ideal district for Dicentra spectabilis since it meets all the conditions this plant requires to grow vigorously, such as a quasi-high altitude and rich precipitation during its period of active growth duration in May. Dicentra spectabilis grows in rocky soil ranging from 300~375m above sea level, 344.5m on average, towards the north, northwest and dominantly in the northeast. The mean inclination degree is $19.5^{\circ}$. Also, upon findings from analyzing solar conditions, the average light intensity during its growth duration, from Apr. to Aug., is 30,810lux on average and it tends to increase, as it gets closer to the end. This plant requires around 14,000~18,000lux while growing, but once bloomed, fruits develop regardless of the degree of brightness. The soil pH has shown a slight difference between the topsoil, at 5.2~6.1, and subsoil, at 5.2~6.2. Its mean pH is 5.54 for topsoil and 5.58 for subsoil. These results are very typical for Dicentra spectabilis to grow in, and other comparative areas also present similar conditions. Given the facts, the character of the soil in Gamakgol has been evaluated to have high stability. Analysis of its vegetation environment shows a wide variation of taxa numbering from 13 to 52 depending on area. The total number of taxa is 126 and they are a homogenous group while showing a variety of species as well. The Dicentra spectabilis community in the Daea-ri Arboretum is an herbaceous community consisting of dominantly Dicentra spectabilis, Cardamine leucantha, Boehmeria tricuspi and Impatiens textori while having many differential species such as Impatiens textori, Pueraria thunbergiana, Rubus crataegifolius vs Staphylea bumalda, Securinega suffruticosa, and Actinidia polygama. It suggests that it is a typical subcolony divided by topographic features and soil humidity. Considering the above results on a comprehensive level, this area is an excellent habitat for wild Dicentra spectabilis providing beautiful viewing enjoyment. Additionally, it is the largest wild colony of Dicentra spectabilis in Korea whose climate, topography, soil conditions and vegetation environment can secure sustainability as a wild habitat of Dicentra spectabilis. Therefore, We have determined that the Gamakgol community should be re-examined as natural asset owing to its established habitat conditions and sustainability.

• Journal of Bio-Environment Control
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• v.10 no.3
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• pp.141-147
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• 2001

To compare to the optical and physical properties of covering materials for plastic greenhouse, EVA(ethylene vinyl acetate, 0.08 mm), polyorefine antifog (0.1 mm), fluoric (0.06 mm), diffused (0.15 mm), polyorefine antidrop (0.15 mm) and PET (polyethylene terephthalate, 0.5 mm) films were used. The small greenhouse (5.4$\times$18.5$\times$2.9 m, W$\times$L$\times$H) investigated during 3 years form 1997 to 1999. After covering materials were used for greenhouse covering during 30 months, UV (300-400 nm) transmittances of diffused film and PET were appeared from 25 to 26%, while those of fluoric film and the other films were 76% and from 63 to 67%. For PAR (photosynthetically active radiation, 400-700 nm), the transmittances of fluoric, antidrop, PET, antifog, EVA, and diffused film were 86.5%, 80.5%, 76.3%, 75.5%, 74.1% and 61.9% respectively. The losses of PAR transmittance of EVA and the antidrop film during period between 7 days and 30 months were higher value 12% and lower value 6% than any other film. Under the canopy of tomato plants, light intensities of the diffused film and the antifog film were 2.5 times and 1.4 times higher than those of PET. Tensile resistances of fluoric film at the break point were the higher than those of antifog film and diffused film. While impact resistance of the antidrop film was the highest value, but the fluoric film was the lowest. Air temperature inside the greenhouse for the day showed to be changed the similar light transmittance of the films. But the increasing order of air temperature for the night was PET, fluoric, antidrop, diffused, antifog and EVA film. Especially, air temperature in the PET was 4$^{\circ}C$ higher than that in the EVA. Solar radiations of the fluoric film, the antidrop film, PET and antifog film in the greenhouse were 32%, 15%, 11% and 4% higher than those of PET. However, those of the diffused film was 7% less than PET.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.848-857
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• 2018

Recently, around the world, active development of new renewable energy sources including solar power, waves, and fuel cells, etc. has taken place. Particularly, floating offshore wind farms have been developed for saving costs through large scale production, using high-quality wind power and minimizing noise damage in the ocean area. The development of floating wind farms requires an evaluation of the Maritime Safety Audit Scheme under the Maritime Safety Act in Korea. Floating wind farms shall be assessed by applying the line and area concept for systematic development, management and utilization of specified sea water. The development of appropriate evaluation methods and standards is also required. In this study, proper standards for marine traffic surveys and assessments were established and a systemic treatment was studied for assessing marine spatial area. First, a marine traffic data collector using AIS or radar was designed to conduct marine traffic surveys. In addition, assessment methods were proposed such as historical tracks, traffic density and marine traffic pattern analysis applying the line and area concept. Marine traffic density can be evaluated by spatial and temporal means, with an adjusted grid-cell scale. Marine traffic pattern analysis was proposed for assessing ship movement patterns for transit or work in sea areas. Finally, conceptual design of a Marine Traffic and Safety Assessment Solution (MaTSAS) was competed that can be analyzed automatically to collect and assess the marine traffic data. It could be possible to minimize inaccurate estimation due to human errors such as data omission or misprints through automated and systematic collection, analysis and retrieval of marine traffic data. This study could provides reliable assessment results, reflecting the line and area concept, according to sea area usage.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.105-118
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• 2000

Anchored measurements (12.5 hr) of suspended sediment concentration and other hydrodynamic parameters were carried out at two stations located at the entrance to Hampyung Bay in summer (August 1999). Tidal variations in water temperature and salinity were in the range of 26.0-27.9$^{\circ}C$ and 30.9-31.5, respectively, indicating exchange offshore and offshore water mass. Active tidal mixing processes at the entrance appear to destroy the otherwise vertical stratification in temperature and salinity in spite of strong solar heating in summer. On the contrary, suspended sediment concentrations show a marked stratification with increasing concentrations toward bottom layer. Clastic particles in suspended sediments consist mostly of very fine to fine silt (4-16 ${\mu}$m) with a poorly-sorted value of 14.7-25.9 ${\mu}$m. However, at slack time with less turbulent energy, flocs larger than 40 ${\mu}$m are formed by cohesion and inter-collision of particles, resulting in a higher settling velocity. Strong ebb-dominated and weak flood dominated tidal currents, in the southwestern and the northeastern part, respectively, result in a seaward residual flow of -10${\sim}$-20 cm $s^{-1}$ at station H1 and a bayward residual flow less than 5.0 cm $s^{-1}$ at station H2. However, mean concentration of suspended sediments at station H1 is higher at flood (95.0-144.1 mg $1^{-1}$) than in ebb (75.8-120.9 mg $1^{-1}$). On the contrary, at the station H2, the trend is reversed with higher concentration at the ebb (84.7-158.4 mg $1^{-1}$) than that at the flood (53.0-107.9 mg $1^{-1}$). As a result, seaward net suspended sediment fluxes ($f_{s}$) are calculated to be -1.7 ${\sim}$-$15.610^{3}$ kg $m^{-2}$ $s^{-1}$ through the whole water column. However, the stations H1 and H2 show definitely different values of the flux with higher ones in the former than in the latter. Alternatively, depth-integrated net suspended sediment loads ($\c{Q}_{s}$) for one tidal cycle are also toward the offshore with ranges of 0.37${\times}$$10^{3}$ kg $m^{-1}$ and 0.21${\times}$$10^{3}$ kg $m^{-1}$, at station H1 and H2, respectively. This seaward transport of suspended sediment in summer suggests that summer-time erosion in the Hampyung muddy tidal flats is a rather exceptional phenomenon compared to the general deposition reported for many other tidal flats on the west coast of Korea.