• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.1-8
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• 2009

The greatest and major cost for cut rose production during winter seasons in Korea is cost of heating the greenhouse. A study was conducted on a cost-efficient heating system to reduce expenses of cut rose growers in times of high energy prices. An infrared heating system utilizing radiant energy has an obvious advantage over other heating methods in that the energy is first used to raise temperatures of plants and other objects and subsequently that of the atmosphere, resulting in faster reaching to desired plant temperatures at a reduced heating cost. In this study the heating effect and heating cost saving of a nano-carbon fiber infrared heating system (NCFIHS) installed in cut rose greenhouses in Gimhae, Gyeongnam Province were analyzed comparatively. In addition growth, quality, and vase life of 'Orange Fresh' roses grown in greenhouses heated by NCFIHS against those grown in greenhouses heated by so called an electrical heating system. In greenhouses with a NCFlHS with a set point air temperature of $20^{\circ}C$, plant temperature was maintained at $1{\sim}2^{\circ}C$ higher than the air temperature, and temperatures of growing bed surface and root zone were maintained at $17{\sim}19^{\circ}C$ throughout cold winter nights. The cost for heating in NCFIHS was about 25 and 51% of that of an electrical heating system and a hot water heating system heated by petroleum, respectively. Growth of roses harvested in greenhouses with a NCFIHS was similar to those grown in greenhouses with an electrical heating system. However, cut roses with more intense petal and leaf colors and a longer vase life (fresh weight and amount of water uptake) were harvested in greenhouses with a NCFIHS as compared to those harvested in greenhouses with an electrical heating system.

• Journal of Bio-Environment Control
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• v.26 no.3
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• pp.175-180
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• 2017

This study was conducted for the domestic new cultivar to expand cultivation area and sustainable production. The new domestic cultivar, 'Jinok' and control cultivar, 'Campbell Early', had been investigated on vine growth and fruit quality by different cultivating conditions as open field, rain shelter and unheated plastic house. The growth period of 'Jinok' was faster than 'Campbell Early'. The harvesting date of 'Jinok' was on 13th of Aug. faster than 'Campbell Early' which was on 17th of Aug., and it was on 25th and 29th of Aug. for 'Jinok' and 'Campbell Early' on field cultivation, respectively. The growing length and width of new shoots were similar among the cropping systems. In the result of fruit characteristic evaluation, the soluble solids content of the 'Jinok' and 'Campbell Early' cultivating on the unheated plastic house were $15.4^{\circ}Brix$ and $15.9^{\circ}Brix$, respectively. In the open field condition, those were $15.9^{\circ}Brix$ and $15.8^{\circ}Brix$, respectively. The titratable acidity and chromaticity were similar among the treatments. In the appearance of past and disease, Phomopsis blight was occurred on mid of June and in the end of cultivation period on about early Aug., the damage by Phomopsis blight was the lowest about 14% in the unheated plastic house cultivation on the 'Jinok' cultivar and it was 39% in the open field condition. However, in the open filed cultivation for 'Campbell Early', Phomopsis blight was highly occurred about 49%. During this period, or the end of cultivation, it is necessary for the intensive control.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.337-343
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• 2020

This study was carried out to evaluate the yield of cuttings according to the planting and runner releasing times of mother plants in order to raise the cutting seedlings of raising seedling period 75 days or more needed for forcing culture of strawberries to be transplanted into the field around the 15^th of September. Three domestic cultivars of 'Maehyang', 'Jukhyang', and 'Kuemsil' were tested. For experiment 1 to determine the yield of cuttings with the change of transplanting time, the mother plant were planted on February 28, March 20, and April 9 in 20 days intervals, and the cuttings were collected two to three times from June 4 to July 1. Experiment 2 was conducted to investigate the yield of cuttings depending on the runner releasing time, the runners were released in three intervals of 20 days, 40 days, and 60 days after planting the mother plant on March 5, and the cutting were collected once to three times from May 29 to June 26. From the comparisons of cutting yield according to the transplanting time of mother plants, February 28 treatment was more 9~25% and 114~165% for each cultivar than March 20 and April 9, respectively (Experiment 1). The yield of cuttings with releasing time 20 days after planting the mother plants had higher by 60~77% and 104~176% for each cultivar than 40 days and 60 days, respectively (Experiment 2). From these results, in case of propagating the seedlings from cuttings needed for field planting around September 15, early planting around in the latter part of February is the best for cuttings yield. In addition, releasing after the removal of the runners produced from mother plants by 20 days after planting gives an advantage over higher yield of cuttings. Consequently, this study suggest to apply an efficient raising seedling system for labor saving and quality improvement in raising seedlings of three strawberry cultivars in Korea.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.388-398
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• 2020

Watermelon yield mainly depends on soil water content controlled by irrigation in a plastic greenhouse. In this study, we investigated the effect of different soil moisture contents affected by irrigation starting point on growth, yield, and physiological responses of small-sized watermelons. Irrigation was initiated at 5 different levels of soil water content as a starting point with soil moisture detecting sensor after 14 days of transplanting, and stopped at 7 ~ 10 days before harvest. These treatments were compared with the conventional periodic irrigation as control. When soil had the lowest moisture content (-50 kPa), the overall shoot growth was retarded, but the root length and root dry weight increased. The photosynthetic parameters (photosynthetic rate, stomatal conductance, and transpiration rate) of watermelon leaves decreased significantly in the lowest soil moisture content (-50 kPa). On the other hand, the photosynthetic rates of watermelon leaves grown with irrigation starting point between -20 and -40 kPa were observed to be higher than those of other treatments. Fruit set rate and marketable fruit yield increased significantly at -30 kPa and -40 kPa. Proline, abscisic acid (ABA), total phenol and citrulline, which are known to contribute to stress tolerance under drought condition, increased as soil water content decreased, particularly, the largest increases were recorded at -50 kPa. From these results, it was found that an appropriate water supply adjusted with an irrigation starting point between -30 and -40 kPa could help to keep favorable soil water content during the cultivation of small-sized watermelons, promoting the marketable fruit production as well as inducing the vigorous plant growth and reproductive development.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.311-324
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• 1994

The quantitative knowledge of N $O_{\gamma}$ (＝N $O_{x}$ ＋HN $O_3$＋/PAN＋N $O_3$ ＋$N_2$ $O_{5}$ ＋HN $O_2$＋N $O_3$$^{-10}$ ＋organic nitrates＋......)distribution is essential in tropospheric chemistry, especially, especially that related to understanding the processes leading to ozone production. Ambient concentrations of NO, N $O_2$, HN $O_3$ and PAN as well as total N $O_{\gamma}$ were measured during June and early July 1992 at a rural site(Candor, NC), in the central Piedmont region of NC. The measurements of N $O_{\gamma}$ species were made in an effort to provide a comprehensive understanding of nitrogen chemistry and to investigate the total nitrogen budget at the site. N $O_{\gamma}$, N $O_2$, and NO showed diurnal variations with maxima in the morning. The maximum N $O_{\gamma}$ concentration reached was 14.5 ppbv, and the maximum concentrations of NO and N $O_2$ were 5.4 and 7.8 PPbv, respectively. The mean N $O_{\gamma}$ concentration as found to be 2.88$\pm$1.58 ppbv(n=743). The mean concentrations of NO and N $O_2$, were found to be 0.15 $\pm$ 0.29 ppbv(n＝785) and 1.31 $\pm$ 0.99 ppbv(n＝769). Products of photochemical oxidants, (N <$O_{\gamma}$-N $O_{x}$ ), such as HN $O_3$ and PAN, as well as ozone showed diurnal variation with maxima in the afternoon and minima at night The fractions of individual reactive nitrogen species to total N $O_{\gamma}$ were investigated and contrasted to the results from remote marine site and rural continental sites. N $O_{x}$ was the major species to total N $O_{\gamma}$(45%). NO concentrations appeared to be nearly constant whether the Prevailing winds were from continental areas or from oceanic areas. Linear regression of $O_3$ with (N $O_{\gamma}$- N $O_{x}$ )/N $O_{\gamma}$ (i.e. percent N $O_{x}$ converted to the photochemical products of N $O_{\gamma}$) yielded ( $O_3$) ＝25.8 〔 N $O_{\gamma}$-N $O_{x}$ 〕/(N $O_{\gamma}$) ＋27, ( $r^{2}$＝0.58). The regression intercept is interpreted as the ozone back ground (intercept=27ppbv) and the slope suggests that 8.6 molecules of ozone are formed per molecule of N $O_{x}$ oxidized products (when the average N $O_{\gamma}$ concentration, about 3 ppbv at the site, is used). The N $O_{x}$ N $O_{\gamma}$ ratio was used as an indicator of the chemical age of airmasses and the ratio showed strong positive correlations with HN $O_3$( $r^{2}$=0.58), PAN ( $r^{2}$=0.46) and $O_3$( $r^{2}$=0.62). Larger N $O_{\gamma}$ and N $O_{x}$ N $O_{\gamma}$ ratio were found when winds came from continental sides. It may suggest that synoptic meteorological conditions and transport of N $O_{x}$ are important in the distribution of N $O_{\gamma}$ and its relationship with photochemical oxidants at the site.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.3
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• pp.33-45
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• 2009

In the industry of landscape architecture, in which the core of production is manpower, the management of manpower is of utmost importance. The industry of landscape architecture, however, is highly sensitive to economic shifts and policy changes; this sensitivity renders the management of manpower-maintaining the balance between supply and demand-often times difficult. Currently, this vicious circle appears to persist in the sense that the industry suffers from a lack of skilled employees, and a new body of skilled laborers from the paucity of jobs. This study, in analyzing current manpower management as well as the prospective supply and demand in the field, looks forward to the stability of the supply and demand in landscape architecture in the nation. According to this study, the number of new skilled laborers-those who have a higher credential than that of "landscape architect-engineer"-is expected to increase by 10% per year. The number of new skilled laborers being 1,137 in 2008, it can be inferred that there will be a new group of 1,251 skilled laborers in the field in 2009. Meanwhile, estimating that the number of current skilled laborers in the field of landscape architecture is 14,783, the demand for new skilled laborers remains approximately 540. The supply of 1,251 skilled laborers outnumbers the demand of 540 by nearly 230%. Hence, the educational institutions of landscape architecture must be prepared to deal with this imbalance between the excessive supply and the lesser demand of skilled laborers. The issue of the excessive supply of manpower is particularly critical, because it may well undermine the competitiveness of the industry as a whole: compared to other related industries such as architecture and civil engineering, for instance. With the customary validation of long work experience no longer in effect, the need for an engineer's license will keep on increasing. It is time that educational institutions took this issue into full account and helped their students to be better qualified and more competent.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.114-119
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• 2012

We have conducted 4 experiments to develop the most environmental and effective use of the two-fluid fog system to prevent and exterminate whiteflies in tomato cultivation. In particular, these experiments used Vitamini tomatoes grown in stand-alone greenhouses at Buyeo Tomato Experiment Station as subjects. Each experiment utilized the fog system in a different way. The first experiment provided the control group, which was subject to the two-fluid fog system without additional humidity control. In the second experiment, the two-fluid fog system controlled the humidity level to be above 70%. The third and the fourth experiment utilized natural substances, which were 1.5 mg/L of Neem Oil and 2 mg/L of Oleic acid respectively, without additional humidity control. From the first experiment, we could observe that a simple use of the two-fluid fog system decreased the density of whiteflies in the greenhouses. This impact of the fog system on whiteflies was greater in the second experiment. By comparing the first and the second experiment, we concluded that whiteflies are more effectively prevented by maintaining a higher humidity level via the fog system's smaller water droplets that float in the air for longer time than the standard fog system in rather dry condition. In the third and the fourth experiments, the extermination level was 78% and 76.4% respectively, comparing only 53% in the first experiment without the humidity control. Therefore, using the natural substances in addition to the humidity control increases the extermination effectiveness. Considering the similar results from the 3rd and the 4th experiments, Oleic acid has a greater appeal for its lower price. Using the two-fluid fog system to both control the humidity on a daily basis and spray the substances for occasional extermination would reduce labor cost and increase production in an environmental way.

• Membrane Journal
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• v.24 no.3
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• pp.213-222
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• 2014

In this study, 2-stage recirculation membrane process was developed for purification of high purity bio-methane for the vehicle fuel application. Pure gas permeation and mixture gas permeation test were done as a function of methane content and pressure in the feed using polysulfone membrane modules. 2-stage membrane plant was designed, constructed in a food waste treatment cite. Dehumidification, dry desulfurization, and desiloxane plants are installed for the removal of $H_2O$, $H_2S$ and siloxane in the biogas. Permeation test were done with the pre-treated methane mixture in terms of methane purity and recovery by adjusting the ratio of membrane area (1:1, 1:3, 2:2) in the first and second membrane modules in the plant. When membrane area of 2 stage increased to $3m^2$ from $1m^2$ at 1-stage membrane area of $1m^2$, the feed rate and $CH_4$ recovery at 95% methane purity were increased from 47.1% to 92.5% respectively. When the membrane area increased two-fold (1:1 to 2:2), $CH_4$ recovery increased from 47.1% to 88.3%. When the feed flow rate was increased, in 1:3 ratio, final purity of the methane is reduced, the methane recovery is increased. When operating pressure was increased, the feed rate was increased and recovery was slightly decreased. From this result, membrane area, feed pressure and feed rate could be the important factor to the performance of the membrane process.

• Journal of Korean Society of Forest Science
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• v.37 no.1
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• pp.1-16
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• 1978

The study describes on the identification and morphological characteristics of each species, ecological characteristics and propagation techniques, and developing utilization measures of the Parthenocissus plants for environment conservation and revegetation of the babe rock-slopes. The following species and varieties are disscussed in this study; Parthenocissus tricuspidata (S. et Z.) Planch. var. veitchii Rehd. var. lowii Rehd. var. pupurea Hort. Parthenocissus quiquefolia (L.) Planch. var. engelmanni Rehd. var. saint-pauli Rehd. var. hirsuta Planch. Parthenocissus henryana Diels et Gilg. Parthenocissus thomsoni Planch. Parthenocissus heptaphylla Small. Parthenocissus inserta (Kern.) K. Fritsch. Parthenocissus laetevirens Rehd. Parthenocissus himalayana Planch. These are, in general, all vigorous self-clinging climbers that will quickly cover a wall and bare rock surfaces with a dense network of branch growths and beautiful green leaves which change to shades of scarlet and crimson before they fall in Autumn. Parthenocissus tricuspidata out of 8 species in the genus Parthenocissus is the most useful plant for the environment conservation including the bare rock-slope revegetation and for the production of food and shelter for wildlifes. This native of Korea clings by means of small rootlike holdfasts (adhesive discs) and holds (tendrils) to stone work or any other solid support, tenaciously.

• Environmental and Resource Economics Review
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• v.13 no.3
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• pp.519-547
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• 2004

This paper analyze problems about scope of specific trade obligations(STOs), principle of dispute settlement procedure, and non-parties in context of the Cartagena Protocol on Biosafety(POB), which based on sub-paragraph 31(i) of DDA WTO Ministrial Declaration. The implications based on result of this study are as follows. First, to accept the wider scope of STOs under POB in Korea, importing country, won't be harmful to LMOs and Bioindustry. Instead, it will ensure a high level of biosafety concerning the import of LMOs. Exporters can take different kinds of trade measures to countervail adverse effect on the export of LMOs in this case. Therefore importer will endure the aftereffect. However, if korea were in exporter's place, to accept the wider scope STOs under POB will not have a good influence on the export of LMOs. Korea, therefore, should devise scheme for responding to debate about the STOs in MEAs, which have to be based on cost-benefit analysis and scenarios taking into account of speed and level in biotechology progress, status and trend of LMOs R&D and production, and condition of other industries. Second, it is not easy to agree with applying to what's rule between the POB and WTO for settlement dispute. Because there is the incompatibility between the POB characterized according to social rationality and WTO's rules for safety and environmental protection characterized according to scientific rationality. This issue have to be discussed for long period due to gap like that. Accordingly Korea, one of major LMOs importing countries, should suggest continuously that the effort is needed to ensure an adequate level of protection in transboundary movements of LMOs and scientific, environmental and socio-economic study. Third, in case of dispute between party and non-party of the POB, the duties under the WTO of non-party of the POB(if WTO member country) is valid. The country, therefore, will try to settle dispute based on WTO's rules. However, international society have to ensure for sound and safe use of LMOs in the field of transboundary movements. Accordingly Korea should devise scheme for preventing the possibility of dispute between party and non-party of the POB(if WTO member country), which is supported by policy options under the POB.