• Korean Journal of Rural Living Science
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• v.8 no.1
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• pp.1-5
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• 1997

In this study we tried to examine the efficiency of the agricultural convenient tool (put-on-style-stool) by observing subjects'physiological responses. For this we measured subjects' heart rate, oxygen consumption, blood lactate level, mean skin temperature and rectal temperature. The results of this study are as follows; Heart rate was 75$\pm$2 beats/min with the put-on-style-stool and 78$\pm$2 beats/min without it (P＜0.01). Oxygen consumption was 3.88$\pm$1.90 $m\ell$/kg/min with the Put-on-style-stool and 5. 06$\pm$0.40 $m\ell$/kg/min without it (P＜0.05). Blood lactate level was 2.39$\pm$0.64 mmol with the put-on-style-stool and 3.38$\pm$0.45 mmol without it (P＜0.05). Mean skin temperature was lower but rectal temperature was higher with than without the put- on - style - stool (P＜0.05 and P＜0.01 respectively) So, using the put-on-style-stool was evaluated positively in farmer's work.

• Korean Journal of Rural Living Science
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• v.9 no.2
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• pp.43-50
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• 1998

To obtain basic data for efficient health plan, we investigated the condition of farmers' health, living behavior, working environment, and cumulative fatigue symptoms by crops (greenhouse melon, rice and red pepper, stock farming, pear, grapes, dropwort, sweet potato, potato, radish. cabbage). The results are as follows; (1) The condition of farmers health : Among them, cabbage cultivators were in bad health concerning cardiovascular system, musculo-skeletal system, and skin condition. (2) Living behavior : $\circled1$ Radish cultivators were in best of their physical condition. $\circled2$ Rice and red pepper cultivators were taking a regular recess as compared with dropwort cultivators. $\circled3$ On concerning bathe, sleeping, and clothes, stock farmers were in relatively bad condition. (3) Working environment : cabbage, greenhouse melon, and dropwort cultivators had relatively Poor working environment. (4) Cumulative fatigue symptoms : $\circled1$ Dropwort cultivators were in the worst of their condition concerning loss of their energy, physical condition. decline of will to labor, sense of unease, and low spirits. $\circled2$ On concerning general fatigue, dropwort, sweet potato, and cabbage cultivator were in bad condition.

• Journal of Environmental Science International
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• v.24 no.1
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• pp.55-64
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• 2015

The dry weight of mother plants' leaves had the highest increase rate in both NS (single-use) and NS+EM (mixed-use) mixed with NS 0.8 (customary use). In seafood amino acid fertilizer (SAF) application, the increase rate was highest in SAF solution at a 300-fold dilution. Mother plants' crown diameter, plant height, leaf length, leaf width, petiole length and leaf number showed the greatest growth amount when NS 0.8 (customary use) was mixed to NS (single-use) or NS+EM (mixed-use) solution. The growth was highest in SAF solution diluted 300 folds, but lowest in SAF solution diluted 100 folds. Of all inorganic nutrients, excluding sulfur, total amount of nitrogen, available phosphorus, potassium, calcium and magnesium had the highest increase rate in both NS (single-use) and NS+EM (mixed-use) with the treatment of NS 0.8 (customary use). Total nitrogen, in particular, was increased by 3.1% in NS 0.4, 6.0% in NS 0.8, and 4.5% in NS 0.8 with the application of NS+EM at a 500-fold dilution compared to NS alone. Total nitrogen amount showed the highest increase rate in SAF solution diluted 300 folds. Total nitrogen, available phosphorus, calcium, magnesium and EC in soils applied with culture solutions (NS, NS+EM) had increasing tendencies after fertilizer application. The results were comparable to those of SAF treatment. The increase rate of each inorganic nutrient composition declined in soils applied with NS+EM solution diluted 500 folds compared to NS alone.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.5
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• pp.667-671
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• 1999

The purpose of this study was to determine the number of skin cold receptor in Korean adult as a part of the study to investigate thermal physiological characteristics of Korean. For this 10 healthy subjects were placed in a climatic chamber and received cold stimulation of 1$0^{\circ}C$ on skin surface of each measuring site with a thermo-stimulator. As a result of cold spot measurement we found 23 points/cm2 at face 13. points/cm2 at chest 16 points/cm2 at abdomen 11 points/cm2 at back 14 points/cm2 at upper arm 16 points/cm2 at forearm 18 points/cm2 at back of the hand 15 points/cm2 at thigh 8 points/cm2 at leg 12 points/cm2 at dorsum of foot 8 points/cm2 at sole of foot in male subjects and in female subjects we fund 18 points/cm2 at face 13 points/cm2 at forearm 11 points/cm2 at at back of the hand 8 points/cm2 at palm 9 points/cm2 at thigh 6 points/cm2 at leg 8 points/cm2 at dorsum of foot 2 points/cm2 at sole of foot. The distributions of cold spots varied in different regions of the body surface and was exceptionally dense in the facial skin. There were some differences among other researchers' results but the cause of those differences are not yet known those are due to individual or methodological difference.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.55-55
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• 2019

Strawberry which is the genus Fragaria under family Rosaceae is one of the most important fruit plants for both fresh consumption and food processing in the temperate and subtropical countries. Propagation of strawberry is achieved either through runners or by in vitro micropropagation. Meristem tips, generally obtained from runners of virus-free plants, are commonly used to establish in vitro cultures, which are employed for mass propagation or as a source of plant material for regeneration and transformation experiments. This study was conducted to determine the optimal natural additives strength to improve sprouting shoot rate of apical meristem of strawberry 'Seolhyang'. Strawberry apical meristem at size (0.2 mm to 0.3 mm) with leaf primordials were cultured on the 1/3MS(Murashige & Skoog) medium supplemented with five natural additives such as coconut milk, maple sap, banana powder and peptone. The sprouting ratio and growth characteristics were evaluated after eight weeks after in vitro culture. Shoot ratio of 'Seolhyang' apical meristem was 72.9% in 1/3MS medium supplemented with maple sap. On the other hand, the low shoot ratio was observed 47.7% in 1/3MS medium supplemented with banana powder. Shoot length was different as natural additives but numbers of leaf was not significantiy different among the natural additives. As a result, the sprouting ratio and plant growth were enhanced effectively in 1/3MS medium with maple sap compared to the others.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.421-426
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• 2013

This study was conducted to investigate the effects of timing of nutrient starvation during transplant production on growth of runner plants and yield of strawberry 'Seolhyang' (Fragaria ${\times}$ ananassa). Nutrient solution supply at the level of EC (electrical conductivity) 0.8 $dS{\cdot}m^{-1}$ was terminated at interval about 10 days between July 25 and September 5. As a result, the growth of above-ground part was inhibited while root growth increased when the nutrient starvation treatment had been brought forward to July 25. It also reduced the T/R ratio significantly and chlorophyll content was tended to be lower than the other treatment. In addition, it significantly promoted the budding, flowering and harvest of first flower cluster. On the other hand, the period of harvest was delayed more than two weeks when the nutrients were continuously supplied after the middle of August. An accumulated marketable fruit yield per plant until the end of January and February was 169 and 266g, respectively in the treatment of nutrient starvation on July 25, which was 71 and 12% increase, respectively, as compared with those in the treatment of September 5. Therefore, the appropriate nutrient starvation in the late season of strawberry nursery period could be expected the increase in yield and income during the winter season by promoting the flower bud differentiation as reducing the endogenous nitrate level of the plantlet.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.219-226
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• 2015

The objective of this research was to investigate the influence of various root media on the growth of mother and daughter plants during propagation and early yield after transplanting of 'Seolhyang' strawberry. To achieve this, daughter plants were fixed to connected small pots that contained expanded rice-hull (ERH), a strawberry-specialized commercial medium (SSCM), soil mother materials (SMM), or loamy sand (LS). Then, growth of daughter plants in above- and below-ground tissue as well as early yield after transplanting to plastic house soil were investigated. The growth of daughter plants in terms of plant height, leaf area and fresh weight were the highest in the SSCM treatment. Root growth in terms of the amount of primary roots and root dry weight were the highest in the treatments of ERH and SMM and the lowest in that of SSCM, among treatments tested. The ERH treatment also showed the highest values among treatments in root length, surface area and volume when roots with 0 to 0.4 mm in diameter were investigated. The flower bud differentiation of daughter plants began on Sept. 3 in the ERH treatments, earlier than the SMM (Sept. 5) and in SSCM (Sept. 7) treatments. The tissue N contents of daughter plants were in the range of 1.41 to 1.55% in all treatments, and no significant differences were observed among treatments. This indicates that the low moisture retention capacity of ERH and water stress, rather than tissue N contents, promote the flower differentiation of daughter plants. In the evaluation of early yield after transplant, the ERH treatment of showed the highest yield in the period from November to December, reaching 667 g fruit weight per 10 plants. The yields per 10 plants in the other treatments were 581 g in SMM, 475 g in SSCM and 295 g in LS. Above results imply that the various root media have different effects on the growth of daughter plants as well as flower bud differentiation. Therefore, improvement in early yield after transplant can be achieved through selection of proper root medium for daughter plant propagation.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.657-663
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• 2012

The Ca deficiency is a serious problem in the propagation of domestically bred 'Seolhyang' strawberry through soil cultivation. The objective of this research was to investigate the impact of the Ca containing fertilizers on the decrease of Ca deficiency symptoms and in the growth of mother and daughter plants. To achieve this, chemicals of 1.125 mM $Ca(OH)_2$, 0.375 mM $MgCl_2$, and 1.25 mM KCl were blended to contain the K:Ca:Mg (4:2:1) and the influence was compared to a commercial fertilizer, Azuro-Calma ($NO_3$-N 13%, $K_2O$ 1%, CaO 16%, MgO 6%), when those were applied as solutions with the electrical conductivity (EC) controlled to 0.6 or 1.0dS ${\cdot}m^{-1}$. During 120 days after transplant, the Azuro-Calma was more effective than the combined fertilizer in the reduction of mother and daughter plants on which Ca deficiency was appeared. The application of two Ca containing fertilizers resulted in the heavier fresh and dry weights of mother plants. The treatments of 1.0dS ${\cdot}m^{-1}$ of two fertilizers were more effective than those of 0.6dS ${\cdot}m^{-1}$. The combined fertilizer was also more effective than Azuro-calma on the growth of above ground plant tissue. The results in length, fresh and dry weight of runners occurred from a mother plants showed that the treatment of 1.0dS ${\cdot}m^{-1}$ of combined fertilizer was most effective followed by those of 1.0dS ${\cdot}m^{-1}$ of Azuro-Calma, 0.6dS ${\cdot}m^{-1}$ of combined fertilizer, 0.6dS ${\cdot}m^{-1}$ of Azuro-Calma, and control. The fresh weights of daughter plants were heavier in the treatments of Ca application than those in the control treatment, but the differences between 0.6dS ${\cdot}m^{-1}$ and control were not significant. The above results indicate that Azuro-Calma is more effective in decreasing plants showing the Ca deficiency symptoms. However, the combined fertilizer of K:Ca:Mg is more desirable when we are concerned about the decrease of crops showing Ca deficiency as well as increase of the growth in above ground plant tissue.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.511-517
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• 2015

This research was conducted to evaluate the influence of root restriction materials and media on the growth of runner plantlets of 'Seolhyang' strawberry in a nursery field. To achieve this, the influence of three kinds of root media on the growth of runner plantlets was monitored when polyethylene film was used as the root restriction material. In addition, the influence of various root restriction materials (RRS) such as transparent polyethylene film (PE), non-woven fabric (NF), perforated polyethylene film (PP), and root proofing sheet (RPS) on the changes in volumetric water content (VWC) and temperature of root media as well as growth of runner plantlet were investigated when expanded rice hull (ERH) was used as the root medium. In the comparison of root media, growth parameters such as leaf area and crown thickness at 20 d after fixation as well as crown thickness and fresh weights of root and above-ground tissue at 40 d after runner plantlet fixation were higher in the ERH treatment than in sandy loam and loamy sand. When the influence of RRS was compared, the VWC of ERH was 55% just after irrigation, but decreased to 26% at just before irrigation. Ranges of the VWC as influenced by irrigation cycle were 16 to 10% in the PP and less than 10% in the NF and RPS. The soil temperature in the PE treatment was around $1^{\circ}C$ lower than in NF, PP, and RPS. The differences between day and night temperatures were also smaller in the PE treatment rather than those in NF, PP, and RPS. The growths of runner plantlet 50 d after fixation showed that plant heights as well as fresh weights of root and above-ground tissue were higher in the PE treatment than in NF, PP, and RPS. NF and PP did not effectively restrict roots inside the medium and the roots of runner plantlets penetrated through the root restriction materials resulting in the formation of root system below the restriction materials. The above results indicate that ERH is more effective than sandy loam or loamy sand as root medium. PE rather than NF, PP, or RPS as root restriction material resulted in better growth of runner plantlets in propagation of 'Seolhyang' strawberry. The results of this research will be used for production of high quality runner plantlets in strawberry propagation.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.518-524
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• 2015

The objective of this research was to investigate the influence of various depths of expanded rice hull (ERH) medium and fixation dates of runner plantlets of 'Seolhyang' strawberry on the growths in nursery field and in plastic house soil after transplanting. The five treatments in medium depths (30, 50, 70, 90, and 110 mm) and four treatments in fixation dates (1st and 15th July and 1st and 15th August) were tested. The growths of runner plantlets were investigated before transplanting to plastic house soil. The early growth and inflorescence rates of crops after transplant to plastic house soil were also investigated. The plant height and fresh weight of runner plantlets were the highest in the medium depths of 50, 70, and 90 mm. The medium depth of 30 mm had higher numbers of first roots, but lower root fresh weight compared to those of 70, 90, and 110 mm. The treatment of 30 mm in medium depth showed poorer growth in all indexes except root length and root weight compared to those of 70, 90, and 110 mm. The runner plantlets fixed on July 1 and July 15 showed good root growth and the weights of ERH adhered to form root balls were 18.3 g and 13.9 g, respectively. The detached amount of ERH was less than 40% in the two treatments when root balls were shaken by a vibratory sieve shaker. The plant growth at 45 days after transplanting to plastic house soil were not significantly different when the runner plantlets were fixed in the period from July 1 to Aug. 1. The inflorescence rates of the first cluster were 93 to 100% when runner plantlets were fixed in the period from July 1 to Aug. 1. By contrast the runner plantlets fixed on the Aug. 15 had a 67% in florescence rate for the first cluster. These results indicate that optimum depth of ERH medium was 7 cm and the ranges of optimum fixation dates are from July 20 to 25.