• Journal of Life Science
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• v.20 no.3
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• pp.437-443
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• 2010

This study was designed to examine the aerobic capacity and ventilatory response during an incremental exercise in elite high school cyclists. Twelve boys ($17{\pm}1\;yr$, $175{\pm}5\;cm$, $70{\pm}9\;kg$) participated in anthropometric measurements, incremental exercise testing, and pulmonary function tests. During incremental exercise testing using a cycle ergometer, their maximal oxygen uptake ($VO_2max$), maximal power output, ventilation, ventilatory equivalents for oxygen ($V_E/VO_2$) and carbon dioxide ($V_E/VCO_2$), respiratory rate, and tidal volume were measured. Time variables such as inspiratory time (Ti), expiratory time (Te), breathing time (Tb), and inspiratory duty cycle (Ti/Tb), as well as inspiratory flow rate ($V_T$/Ti) were assessed. Pulmonary function of vital capacity (FVC), forced expiratory volume in one second ($FEV_1$), $FEV_1$/FVC, and peak expiratory flow were evaluated. Their $VO_2max$, maximal heart rate, and Wmax were $57.5{\pm}3.9\;ml{\cdot}kg^{-1}{\cdot}min^{-1}$, $194.1{\pm}8.6\;beat{\cdot}min^{-1}$, and 452 W, respectively. $VO_2max$ was not related to any anthropometric parameters. Most ventilatory variables progressively increased with exercise intensity. As intensity increased, Ti, Tb, Tb decreased while Ti/Tb was maintained. Below an intensity of 250 W, height, weight, body mass index, and body surface were highly correlated with $V_T$/Ti and Ti/Tb (p<0.05). Collectively, $VO_2max$ appeared to be lower than adult cyclists, suggesting a different pattern of ventilatory control as age advances. Morphological characteristics were not related to $VO_2max$ in the population. Time variables of ventilatory response seemed to be related only at an exercise intensity level of less than 250 W. $V_T$/Ti may be related to exercise endurance capacity, but Ti/Tb was similar to adult cyclists.

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1417-1423
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• 2011

For evaluating the effect of various organic fertilizer ratios on the Spiraea${\times}$bumalda 'Gold Mound' growth, a container green wall system experiment was conducted in a greenhouse at Konkuk university. The experimental planting grounds were prepared with different organic fertilizer ratios ($A_1L_0$, $A_8L_1$, $A_4L_1$ $A_2L_1$ and $A_1L_1$) and with drought tolerance and an ornamental value Spiraea${\times}$bumalda 'Gold Mound' was planted. The change in soil moisture contents, plant height, number of branches, number of dead leafs, number of leaf, number of shoots, length of node, length of leaf, width of leaf, root-collar caliper, chlorophyll contents and survival rate were investigated from April to Jun 2010. 1. The result of soil moisture contents was analyzed with weight unit in the container green wall system during the dry summer season. The soil moisture contents were significantly enhanced in the container green wall system in increasing order as the amount of fertilizer level increased $A_1L_1$ > $A_2L_1$ > $A_4L_1$ > $A_8L_1$ > $A_1L_0$. 2. Compared to the control treatment (amended soil with 100% + organic fertilizer 0%) application, the highest plant growth was observed in the treatment of $A_2L_1$(amended soil with 67% + organic fertilizer 13%) application. However, the differences between the organic fertilizer ratio treatments of $A_1L_1$, $A_4L_1$, $A_8L_1$, and the $A_1L_0$ organic fertilizer application were mostly not significant. 3. The survival rate increased with the increasing application of organic fertilizer, but in the control treatment (amended soil with 100% + organic fertilizer 0%) application all the plants died. Experimental results from the presented study clearly demonstrated that the organic fertilizer improved the survival rate more than the Spiraea${\times}$bumalda 'Gold Mound' growth at different levels of organic fertilizers. This strain can be utilized as a plant growth application in living wall systems during the dry summer season. Therefore, Spiraea${\times}$bumalda 'Gold Mound' is expected to be a highly valuable shrub for the green wall system if it should be considered in integration with stormwater retention or as a soil conditioner for increasing soil water contents in planting ground.

• Journal of Bio-Environment Control
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• v.9 no.2
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• pp.85-93
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• 2000

This study was carried out to investigate the effects of several substrates and ratio of NO3--N to NH4--N in nutrient solution on growth, yield and mineral uptake of sweet pepper(Capsicum annuum L.) in bag culture. The content of minerals such as P, K, Ca and Mg showed difference in concentration among media: P and Mg were the highest in vermiculite in vermiculti+rice hull, K in perlite+vermiculite and Ca in perlite+peatmoss; with the lowest in the single perlite medium respectively, Ca of mineral made fairly higest level in concentration compared with the others in all of the media. The concentration of mineral content was lower in the ratio of 8:2 than that of 10:0. Admitting that the pH made difference depending on the kind of substrates and ratios of NO3--N to NH4--N. The pH of 10:0 ratio in all the substrates was higher and more stable than that of 8:2. The range of EC in all the substrates showed from 1.78ds·m-1 to 2.10 ds·m-1, which was optimum range for growth of sweet pepper, and range of EC is larger in 8:2 ratio than that in 10:0 ratio. Plant height and stem diameter were nothing to do with the kind of substrates, but leaf area was the largest at vermiculite+rice hull of the 8:2 ratio, fresh and dry weights were heavier at peatmoss+carbonized rice hull, but were the lightest at perlite. All indexes related to the growth which had something to do with the kind of substrates higher in 8:2 ratio than those in 10:0 ratio. The number of fruit and fresh weight related to the ratio of the 8:2 were the highest as 17.5 at vermiculite+rice hull with 1,588g of fresh weight, while the yield from perlite was the lowest. The number of fruit was the highest as 16.4 at virmiculite+rice hull, yield was the higest as 1,394a at perlite+ peatmoss. The yield of 8:2 ratio at all substrates was higher than that of 10:0 ratio. Of the mineral content related to the plant part, K+ and Mg2+ were higher in concentration at leaf; Ca2+ were higher at root; PO4- was higher at stem and fruit; The content of mineral showed no difference between the ratio of the 8:2 and the ratio of the 10:0 with no regrading to the difference of mineral content among substrates; and K+, Ca2+, and Mg2+ uptake of sweet pepper were higher at 10:0 ratio than that of 8:2; 2while PO4- uptake of sweet pepper was lower at 10:0 ratio than that of 8:2 ratio.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.212-217
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• 2016

This study was conducted to investigate the effect of nursery period on growth and yield attribute of green papaya (var. Red lady). The nursery period was 3, 5, 7, 9, 11 and 13 months and the green papaya was transplanted on 15 April, 2015 in a non-heated greenhouse. The plant height, node number and fresh weight of nursery plant were increased as the nursery periods increased. The growth of green papaya with 13 months nursery period was better than those of other treatments. First harvest after transplanting was increased as the nursery periods were shorten. It took 137 days (18 August) at 13 months treatment, and 184 days (2 October) at 3 months treatment. The fruit length and diameter were smallest at 3 months treatment and there was no significant difference among other treatments. The fruit yield was also influenced by the nursery periods, the commercial yield was also increased as the nursery periods increased. The commercial yield was highest at 13 months treatment (3,172kg/10a), followed by 11 (2,247kg/10a) and 9 months treatment (2,357kg/10a). At 7 and 5 months treatment were 1,942kg/10a and 1,787kg/10a, respectively and the yield was lowest at 3 months treatment (1,443kg/10a). The commercial yield was significantly decreased under 7 months treatment. Although the harvest time of 11 months treatment was earlier than that of other treatments in non-heated greenhouse, 9 month treatment will be more recommendable for green papaya production because of operating costs.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.191-198
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• 2018

The objective of this study was to determine the effects of combination of air temperature and soil water contents on growth, physiological disorder rate, and yield of garlic. This experiments has been carried out in the typical plastic house (one side open and other side installed ventilation fans) which was maintained gradient air temperature (maximum different value of air temperature : $6^{\circ}C$). The excessive irrigation (EI) set at $0.34m^3/m^3$ soil moisture contents. The significant differences found in the growth parameters of garlics as affected by air temperature and soil moisture conditions. The plant height of garlic with combination of ambient $(A)+6^{\circ}C$ and optimal irrigation (OI; set at $0.22m^3/m^3$ soil moisture contents) treatments represented 47.4 cm/plant, which was the highest among all the tested treatments. The leaf length and width showed the greatest, which were 16.1 and 2.4 cm/plant, respectively, in $A+6^{\circ}C-OI$. The physiological disorder ratio was higher as 12.9% at $A+6^{\circ}C-OI$ and was not occurred at ambient temperature with EI compared with OI treatment. The bulb and clove weight were dramatically decreased at $A+6^{\circ}C$ temperature treatment. The yields were decreased by 51% in OI at $A+6^{\circ}C$ and $A+3^{\circ}C$ temperature treatment. Those results indicated that yields were decreased and ratio of physiological disorders was increased by high temperature treatments.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.189-195
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• 2020

This research was carried out to find the proper number of stem training and position of fruit setting that can be stably produced for the cultivation in small and medium types of watermelon during winter. The treatments for the number of stem training were 2-, 3-, 4-stems, respectively. Growth characteristics (plant height, stem diameter, no. of node, etc.) by number of stem training were higher in 2-stem than in 3-4-stem. However, Fruit characteristics such as weight, length, width were high in the 4-stem. There is no significant difference between the soluble solids and fruit setting rate depending on the stem training. The position of fruit setting were three points: 2nd, 3rd, 4th female flower positions. The fruit setting is one fruit per plant. The average fruit setting nodes of 2^nd, 3^rd and 4^th female flowers were 11.5, 15.8 and 23.1 nodes, respectively. The 4^th female flower was 0.8 kg heavier than 2^nd female flower because of its increased weight as position of fruit setting was higher. However, the soluble solids decreased as the position of fruit setting increased, with the second female flower being 1.3°Bx higher than the 4^th female flower. The Fruit setting rate was no significant difference. Considering the growth and fruit characteristics, it is believed that the small and medium-sized watermelon in winter will have a high quality production of watermelon when the stem training is 3-stem and the position of fruit setting is 3^rd female flower. However, it is thought that additional studies are needed to stabilize the income of watermelon-growing farms, such as planting distance and adhesion of small and medium-sized varieties.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.171-180
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• 2020

The effect of three different light qualities on growth, photosynthesis, quality and safe parameters of hydroponic cultivated spinach (Spinacia oleracea L.) were investigated indoor. Three different light qualities were created of red (660 nm), blue (450 nm) and green (550 nm) LEDs corresponding at ratio R660/B450 = 4/1 (RBL); R660/B450/G550= 5/2/3 (WWL); R660/B450/G550 = 1/1/1 (WL), which were tested at the same intensity (PPFD =190 μmol m^-2 s^-1). The results showed that the plant height and leaf number were the lowest in WL treatment. The SPAD, Net photosynthesis rate Pn, Fv/Fm, Leaf area index LAI values and all parameters of root characteristics were the highest in RBL treatment and were significantly different from two others. Fresh weight of stem, leaf and root, dry weight of root in the three light qualities were significantly different. In contrast, the highest K⁺ content in WL was different from WWL and RBL treatments, while Ca²⁺ and Fe²⁺ content were the highest in the RBL treatment. Vitamin C content was significantly different between the three treatments. nitrate and oxalic acid contents were the highest in WL treatment, whereas soluble-solids contents and vitamin C contents were the highest in RBL treatment. Oxalic acid, nitrate contents were observed tending reduced under WWL although oxalic acid content in RBL treatment was not different from WL and WWL treatments. In all three different light treatments were not detected Salmonella, E.coli. Our results suggest that RBL may be appropriate light for growth of spinach, but supplementary green light to a combination of red and blue LEDs at the reasonable rate can change the quality of spinach in a positive direction. Hydroponic cultivated spinach was safe for users.

• Korean Journal of Agricultural Science
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• v.35 no.2
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• pp.119-126
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• 2008

This study was carried out to find the botanical characters and effect of weed control for herbicides treatment after barley sowing. Barley variety used in study was "Yuyeon", hood-type awn for whole crop forage use, which developed at RDA in 2004. Sowing date was on 10th October, 2007, and was drilled as $60{\times}20cm$. Herbicides were treated on 2th day after barley sowing. Measured items were number and kinds of weeds at each treatment and growth characteristics and grain yield in barley. Cerastium holosteoides var. hallaisanense among weeds surveyed at tillering stages in Butachlor treatment were highly appeared, but Alopecurus aequalis var. amurensis did not appeared while Alopecurus aequalis var. amurensis was 39 plants and Capeslla bursa-pastoris was 37 plants in check. Occurrence of the Capeslla bursa-pastoris at primary survey and Cerastium holosteoides var. hallaisanense in ripening stage were high, while Alopecurus aequalis var. amurensis did not emerged. Botanical characteristics of barley each as plant height, number of tillers and spiklets per plant. surveyed at ripening stage were higher than check. Grain yield per 10a was the highest at Alachlor among treatments, while dry matter of leaf and culm were similar among treatments. Therefore, effect of yield increasing of barley by herbicide after sowing was reconfirmed through this study. Especially, effect of Alachlor was lightly high compared with others.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.2
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• pp.125-140
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• 2011

The remnant of temporary cement on the intaglio surface of cast restoration may have a negative effect on the retentive strength of permanent cement. This study was to evaluate the effect of temporary cement cleaning methods on the retentive strength of cementation type implant prostheses. Prefabricated implant abutments - height 5.5mm, diameter 4.5mm, 6 degree axial wall taper with chamfer margins were used. Forty copings-abutment specimens were divided into four groups(each n=10) according to the cleaning methods for temporary cement(Temp-$Bond^{(R)}$) as follows : no temporary cementation(the control group), orange solvent, ultrasonic cleaning, air borne-particle abrasion. After the application of temporary cement and the separation, the cleaning procedure was performed according to the protocol of each group. The specimens were cemented with $Premier^{(R)}$ Implant $Cement^{TM}$. After the permanent cementation, the specimens were subjected to thermocycling and pulled out from the specimens with a universal testing machine at a cross-head speed of 0.5mm/min. After the retentive strength test, all the specimens were cleaned using ultrasonic cleaning, abraded with air borne-particles, and steam-cleaned. Likewise, the specimens were temporarily cemented(Temp-$Bond^{(R)}$ NE), cleaned according to the protocol of each group, cemented with $Premier^{(R)}$ Implant $Cement^{TM}$ and subjected to thermocycling and measurement of their retentive strength. The mean of group with orange solvent were significantly lower than those of other groups(p<0.05). There was no significance between group with ultrasonic cleaning and group with air borne-particle abrasion. Group with ultrasonic cleaning and group with air-particle abrasion were no significance at control group. There was no significance between group cemented with Temp-$Bond^{(R)}$ and group cemented with Temp-$Bond^{(R)}$ NE. Within the limitation of this study, it can be concluded that the temporary cement cleaning method with only orange solvent may have a negative effect on the retentive strength of permanent cement. Ultrasonic cleaning and air borne-particle abrasion methods are recommended for the temporary cement cleaning method on cementation type implant prostheses.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.322-326
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• 2012

Recently, researches related to plant factory system has been activated and production of Ssam-vegetables using artificial lighting has been increasing. In South Korea, Ssam-vegetables are very popular and the consumption is increasing every year. Because leaf vegetables cultivated under hydroponic systems are more preferable rather than those cultivated by soil culture in Korea, the plant factory system would be more effective in production of Ssam-vegetables. Therefore, this study was carried out in order to analyze the yield and vitamin C contents in red mustard (Brassica juncea L.) and pak-choi (Brassica campestris var. chinensis), which are used a lot for the Ssam-vegetables in South Korea, as influenced by different concentrations of the nutrient solution in a plant factory system. As a results, there was no significant differences in the plant height among the treatment of EC in the nutrient solution, but for red mustard plants, the number of leaves tended to decrease in the treatment with higher EC. Leaf area of pak-choi plants was significantly increased in the higher EC, while the fresh weight had a tendency to increase along with increasing EC in the nutrient solution for both crops. The photosynthetic rates did not show a distinct tendency by EC levels for red mustard plants, but for pak-choi plants, it tended to be higher at the high EC. The contents of ascorbic acid in leaves were higher with decreasing EC concentration in the nutrient solution for red mustard plants, while the content was the highest at EC $2.0dS{\cdot}m^{-1}$ for pak-choi plants. In summary, considering the marketable yields and vitamin C at different nutrient concentrations in a plant factory, the optimal concentration for red mustard and pak-choi plants was thought to be EC $2.0{\sim}2.5dS{\cdot}m^{-1}$.