• Korean Journal of Applied Biomechanics
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• v.26 no.4
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• pp.433-441
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• 2016

Objective: The purpose of this study was to understand the injury mechanism and to provide quantitative data to use in prevention or posture correction training by conducting kinematic and kinetic analyses of risk factors of lower extremity joint injury depending on the change of direction at different angles after a landing motion. Method: This study included 11 men in their twenties (age: $24.6{\pm}1.7years$, height: $176.6{\pm}4.4cm$, weight: $71.3{\pm}8.0kg$) who were right-leg dominant. By using seven infrared cameras (Oqus 300, Qualisys, Sweden), one force platform (AMTI, USA), and an accelerometer (Noraxon, USA), single-leg drop landing was performed at a height of 30 cm. The joint range of motion (ROM) of the lower extremity, peak joint moment, peak joint power, peak vertical ground reaction force (GRF), and peak vertical acceleration were measured. For statistical analysis, one-way repeated-measures analysis of variance was conducted at a significance level of ${\alpha}$ <.05. Results: Ankle and knee joint ROM in the sagittal plane significantly differed, respectively (F = 3.145, p = .024; F = 14.183, p = .000), depending on the change of direction. However, no significant differences were observed in the ROM of ankle and knee joint in the transverse plane. Significant differences in peak joint moment were also observed but no statistically significant differences were found in negative joint power between the conditions. Peak vertical GRF was high in landing (LAD) and after landing, left $45^{\circ}$ cutting (LLC), with a significant difference (F = 9.363, p = .000). The peak vertical acceleration was relatively high in LAD and LLC compared with other conditions, but the difference was not significant. Conclusion: We conclude that moving in the left direction may expose athletes to greater injury risk in terms of joint kinetics than moving in the right direction. However, further investigation of joint injury mechanisms in sports would be required to confirm these findings.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.4_2
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• pp.593-601
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• 2020

This study was conducted to analyze the physical strain with heart rate monitor in timber harvesting operations in order to reduce occupational accidents. The timber harvesting activities are manual cutting(felling, limbing and bucking) with a chainsaw and extraction by cable yarder. The study took place on Japanese larch stand. The average height was 26m and average diameter at breast height(DBH) was 3 7cm. The havest unit was gentle slope to steep slope. Results showed that the heart rate increases for chocking, felling, limbing and bucking were 94.0%, 87.9%, 84.8% and 56.4% respectively. The rate of Work Load Index was higher in the limbing(61.4%) activity than other activities chocking(55.2%), felling(54.1%) and bucking(32.1%). During 50% working heart rate test it was found that limbing(1.09), chocking(1.05) and felling(1.04) was exposed to high work intensity compared to bucking(0.83). The results showed that maximum acceptable work times(felling, chocking and limbing) were 2.30 hour, 1.85 hour and 1.60 hour respectively. To avoid occupational accidents, timber harvest workers may use a suitable working hour schedule to felling, chocking, limbing.

• Korean journal of food and cookery science
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• v.29 no.1
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• pp.29-36
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• 2013

The present study was conducted to supply more scientific information for standardization of preparation method of Gyungdan and to determine the standard for manufacturing procedure adapted with mechanically impacting technology (MIT) for mass production. The optimum preparation condition for non-waxy Gyungdan adapted with MIT was 35% of water, 0.5% of wheat flour (w/w of soaked rice), and mechanically impacting for 10 min at 450 rpm. In the present study, standardization of manufacturing procedure for merchandizing of Gyungdan was established with width, weight, and height. Average of Gyungdan adapted with MIT at 90 rpm (stuffing speed) and 46.58 Herz (cutting speed) is 18.3 g of weight, 28.4 mm of height, and 32.4 mm of width. Hardness, as a main parameter of texture profile, of Gyungdan was maintained lower than 100 g up to 3 days at the storage of $20^{\circ}C$ and up to 70 days at the storage of $-20^{\circ}C$. And, it was performed to develop rice cake as meal-replacement adapted with MIT and sub-ingredients such as strawberry, pumpkin, and mugwort. Gyungdan prepared under controlling manufacturing condition of MIT was supplemented with 0-1.6% of sub-ingredients, respectively. In sensory tests, the best substitute ratios of strawberry, pumpkin, and mugwort were 1.6%, 0.8%, and 1.6%, respectively. With the results above, not-harden Gyungdan supplemented with sub-ingredients and various stuffs can be expected to application for wheat-substitute meal-replacement.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.74-78
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• 1984

The highest cutting ratio and the best growth performance of the P. alba, P. alba ${\times}$ P. glandulosa and P. glandulosa were at -0.05 bars of soil water potential (${\Psi}_s$). Their growth and rooting ability of cuttings were better in suitable soil moisture contents, 19.650, but were worse in low soil moisture contents, 11.41% and 16.66%, respectively. Specially, P. alba ${\times}$ P. glandulosa appeared hybrid vigor in high soil water potential (${\Psi}_s$= -0.05 bars) but not appeared it below ${\Psi}_s$ = -0.5 bars. It is believed that P. glandulosa is a natural hybrid between P. davidiana and P. alba in view of morphological characteristics. Aspen, normally, does not have the rooting ability of cuttings, however, P. glandulosa showed the rooting ability, though the ratio was low, 23%. It is estimated that this rooting ability was originated from P. alba. In addition, its growth rate was between P. alba and P. davidiana, and the sensitivity of water requirement for the growth was also really equal to P. alba. This facts prove P. glandulosa to be natural hybrid between P. alba and P. davidiana.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.3
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• pp.192-198
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• 2020

Root extension is the most important growth change that occurs during cultivation. We analyzed growth changes according to young seedling age, temperature, and the degree of root cutting in order to identify factors affecting rooting after transplanting. Root cutting did not affect plant height growth rate, root growth rate was increased in plants that experienced root cutting, and 14-day-old seedlings exhibited a higher growth rate than 7-day-old seedlings. Growth temperature experiments revealed that elongation was high at 25℃ and 28℃, but tended to be low at 18℃, and root elongation was high at 22-28℃ for 7-day-old seedlings and 22-25℃ for 14-day-old seedlings. Nitrogen absorption decreased in the following growth temperature order: 25, 28, 22, 18℃, and differences in nitrogen absorption under different growth temperatures tended to be lower in 7-day-old seedlings. The amount of nitrogen taken up by roots did not differ significantly between the short root treatment and the control, and 7-day-old seedlings tended to start nitrogen absorption faster than 14-day-old seedlings. Root vitality was highest in short-rooted 7-day-old seedlings with 3 cm of root remaining, and vitality also tended to be high in short-rooted 14-day-old seedlings.

• Journal of the Korean Society of Food Culture
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• v.3 no.3
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• pp.309-317
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• 1988

The effects of $CaCl_2$, K-sorbate, and fermented fish sauces and blanching on the texture of Chinese cabbage of Kimchi were evaluated. The addition of salt-fermented shrimp or salt-fermented anchovy accelerated the pH reduction, acidity increase and reducing sugar consumption, but K-sorbate, Ca-chloride and blanching suppressed the ripening process of Kimchi. The latter retarded the softening rate of Chinese cabbage during Kimchi fermentation, as demonstrated by the cutting force, compression force, recovered height and work ratio. The sensory evaluation confirmed the results of instrumental texture measurments. The instrumental measurements, i.e. pH, acidity cutting thickness, cutting force and compression test parameters, showed acidity acidity was calculated as % lactic acid attributes, i.e. the preferences for taste, appearance and texture, and the level of crispiness, hardness, chewiness and fibrousness. The pH of Kimchi was appeared to be an important quality parameter, whiih had significant correlations with the taste, appearance, chewiness, hardness, fibrousness and crispiness.

• Journal of Bio-Environment Control
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• v.13 no.2
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• pp.112-119
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• 2004

Objective of this research was to evaluate the effects of nutrient solution strength and Arbuscular Mycorrhizal Fungi (AMF, Glomus sp.) on growth and flowering of potted miniature rose (Rosa hybrids L. cv 'Scarlet'). To achieve this, plants cultured with six different strength of Japanese Horticultural Experiment Station solution (0.125, 0.25, 0.5, 1.0, 2.0, and $4.0\;{\times}\;{full}$ strength) and inoculated with AMP at cutting and transplanting. Leachate EC increased as solution strength were elevated. The leachate EC were not different between non-inoculated plants and AMF treatment at cutting, but significantly decreased when plants were inoculated with AMF at transplanting. The elevated strength of nutrient solution resulted in decrease of leachate pH. When plants were inoculated AMF at transplanting, leachate pH was lower than those of non-inoculated plants and inoculated with AMF at cutting. At harvesting (93 days after transplanting), plant height, leaf width, number of branches and shoot fresh and dry weight of rose 'Scarlet' increased with elevated nutrient solution strength. AMF treatment at transplanting of potted rose 'Scarlet' showed the best results in growth such as chlorophyll content, number of flowers, and shortening the days required to flower. The content of N, P, K, and Mn in leaf tissue of potted rose increased by elevated nutrient solution strength and AMF treatment, while the tissue Na contents decreased by an AMF treatment.

• Korean journal of applied entomology
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• v.45 no.3 s.144
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• pp.327-331
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• 2006

This study was carried out to determine the economic injury level of the rice leaffolder,Cnaphalocrocis medinalis G.. The damage aspects of rice plant (at tilling stage) by leaf folders at different larval density per plant were studied in pot experiment (24 cm in diameter, 18 cm in height). One leaf folder consumed 6-7 leaves during larval stage. The damage by leaf folders was simulated by cutting off 0, 10, 30, 50, 70, and 90% of leaves before and after heading stage July 15th (at panicle initiation stage) and August 15th (at milk stage), respectively. When leaves were cut before the heading of rice, the linear relationships between the leaf cutting rate (X) and each factors of yield (Y) were as following; for grain maturity it was Y = -9.379X + 83.630 ($R^{2}=0.493$),\;Y = 0.139X + 0.490 ($R^{2}=0.925$) for yield, and Y = -4.880X + 81.116 ($R^{2}=0.665$) for head rice. When leaves were cut after the heading of rice, it was Y = -23.0l4X + 83.589 ($R{2}=0.915$), for grain maturity, Y=0.141X + 3.466 ($R^{2}=0.842$) for yield, and Y = -13.795X + 81.964 ($R^{2}=0.898$) for head rice. We found that when leaf cutting after the heading stage caused more damage than before the heading in terms of yield and yield components. Based on theses results the economic threshold level was estimated to be 30% and 7% leaf loss before and after heading stage.

• Restorative Dentistry and Endodontics
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• v.12 no.1
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• pp.131-147
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• 1986

The purpose of this study was to observe the color matching of lining or filling materials according to the remaining tooth material. Twenty-seven freshly extracted human central incisors were used in this experiments. The teeth were stored in saline solution at room temperature after extraction. All teeth were cut parallel to the tangent to height of contour on labial surface from the lingual surface until the pulp were completely removed. Then 27 teeth were devided into 0.5mm, 1.0mm and 1.5mm reduction groups according to the thickness of cutting the lingual surfaces of teeth. The specimens of control group were three teeth of 27 teeth with cutting the lingual surface same mode as above described. In the specimens of experimental groups, 8 kinds of lining and filling materials; FUJI IONOMER TYPE II (G-C Co. Japan), LINING CEMENT (G-C Co. Japan), Dycal (Caulk, U.S.A.), CLEARFIL F II (Kuraray Co. Japan), Crown Bridge & Inlay Cement (G-C Co. Japan), Copalite (Harry J. Bosworth Co. U.S.A.), HY-BOND (G-C Co. Japan) and LIV-CENERA (G-C Co. Japan); applied on the back of 24 teeth with 0.5mm, 1.0mm and 1.5mm cut thickness of lingual surfaces. Three teeth of control group did not applied linging or filling materials on the back of 3 kinds of different thickness of cutting the lingual surfaces. The absorbances of total 27 specimens were obtained by reflection spectrophotometer. (Cary 17 D, Varian Co, U.S.A.) The following conclusions were drawn from above the results; 1. The absorbance patterns in both experiment and control groups were gradually decreased with increasing wavelength of spectra. 2. The absorbance patterns were not decreased in relation to the kinds of lining or filling materials, but the amount of the remaining tooth materials. 3. In 0.5mm reduction group, FUJI IONOMER TYPE II, LINING CEMENT, LIV-CENERA and Copalite applied on the back of cut lingual surface showed similar absorbance patterns as control group. 4. The specimens which were reduced up to 1.0mm thickness and lined with FUJI IONOMER TYPE II and LINING CEMENT showed the comparable absorbance patterns to the control group. 5. In case of HY-BOND application after 1.5mm reduction were observed the similar absorbance pattern as compared with control group. 6. When Dycal, CLEARFIL and Crown Bridge & Inlay Cement were applied to cut teeth surfaces, there were much differences of absorbance between control groups and experimental groups.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.261-265
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• 2008

This study was carried out to investigate the effects of stem cutting ages and harvest time on the growth and yield of potato 'Dejima' in aeroponics. The stem cuttings were produced from in vitro plantlets and transplanted into an aeroponic system with 20, 30, 40 and 50 day-old stem cuttings (DOS). Tubers were harvested 60, 70, 80 and 90 days after transplanting (DAT) and sorted into following categories: $1{\sim}5$, $5{\sim}10$, $10{\sim}20$, $20{\sim}30$, $30{\sim}40$ and over 40 g. Plant height from the 40 DOS was the highest during the growing periods but no significant difference was observed on 75 DAT. The tuber weight increased until 90 DAT with the greatest weight of tubers in the 20 and 40 DOS. However, there was no significant difference among 20, 30 and 40 DOS in the number and weight of tubers. Harvesting at 80 and 90 DAT increased the number of tubers over 5 g, which are usually considered as appropriate for direct field planting.