• 반도체디스플레이기술학회지
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• 제6권4호
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• pp.17-22
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• 2007

Vibration isolation equipments are mostly required in precise measurement and manufacturing system. Among all the vibration isolation equipments, air-spring is the most widely used equipment because of low resonant frequency and high damping ratio. In this study, we used Takagi-Sugeno fuzzy method to design an active vibration isolation system using air-spring, and compared the fuzzy method with passive control method and PID control method. Due to the non-linearity characteristics of air-spring, fuzzy controller was verified to be the most effective both in simulation and experiment.

• International journal of advanced smart convergence
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• 제12권4호
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• pp.451-457
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• 2023

Global warming is causing abnormal climates such as floods, droughts, and typhoons all over the world. According to some scientists, carbon dioxide emitted from automobiles is the main cause of global warming. To cope with this, each country is making efforts to replace the existing fossil fuel-powered engine-driven cars with electric vehicles. In order to commercialize small electric vehicles in Korea, it is necessary to solve many problems such as improvement of hill climbing capacity and improvement of power performance. In this study, we propose a proprietary model for a continuously variable transmission(CVT) of a small electric vehicle that can be operated on hills, in which a spring is mounted on a driving pulley and a driven pulley. A prototype of the CVT model using a spring was manufactured and attached to a small electric vehicle body.

• 한국초지조사료학회지
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• 제9권1호
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• pp.1-6
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• 1989

This field experiment was carried out to determine the effects of fertilizer application time in spring on the growth, crude protein(CP) content and dry matter(DM) yield of grasses for soiling. Application times of fertilizer were March 10, 20, 30, April 9 and 19, and control (non-fertilized) plot was involved. All fertilized plots were also treated with single- and compound fertilizer. The first harvesting date for soiling was May 12, and the regrowth soiling yield was investigated on June 9, 1988. In all fertilized plots, the growth, DM yield, CP, CP yield and regrowth yield of gasses were significantly increased compared with control, and the best grass growth, DM yield, CP, CP yield and N recovery were observed on March 30 and April 9 among all fertilized plots. And there were not significant differences between singleand compound fertilizer treatment in grass growth, DM yield and CP content. On March 30 and April 9 in this experiment, the accumulated temperature was 120 and 200^{\circ}C.$ and the subsoil temperature at 10 cm depth was 8 and 10^{\circ}C.$. Considering the average meteorological condition in Suwon area, the optimum application time of spring fertilizer for soiling may be recommended from April 3 to April 10.

• 한국의류학회지
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• 제32권4호
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• pp.586-597
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• 2008

The purpose of this study is to find out the relationship between the personal color types and personality types and analyze the differences in color preference according to the personal color types and personality types. This study was conducted by using questionnaire method and drape diagnosis method in parallel. The results are as follows. First, in case of introversion (I), the summer type took the most and spring, fall, and winter type followed respectively. Also in the case of extroversion (E), the summer type took the most and spring, fall, and winter type followed respectively. Second, the spring type preferred yellow, the summer type, blue, the fall type, brown, and winter type, blue the most. For the preference of the tone of color, all 4 types preferred the pastel tones the most. For the lipstick colors, the spring and summer type preferred the pink color, the fall type, orange and winter type, red the most. For eye shadows, the spring type preferred orange, summer type, blue, fall type, orange and winter type, pink. For nail colors, all 4 types preferred pink the most. Third, the most preferred color for introversion (I) was red group. In contrast, the most preferred color for extroversion (E) was yellow group. In the tone of preferred colors, both introversion and extroversion preferred the pastel tones the most. In lipstick colors, eye shadow colors, and nail colors, both introversion and extroversion preferred the pink group colors the most.

• Journal of Mechanical Science and Technology
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• 제20권9호
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• pp.1382-1389
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• 2006

Dynamic responses of a simply supported beam with a translational spring carrying a moving mass are studied. Governing equations of motion including all the inertia effects of a moving mass are derived by employing the Galerkin's mode summation method, and solved by using the Runge-Kutta integral method. Numerical solutions for dynamic responses of a beam are obtained for various cases by changing parameters of the spring stiffness, the spring position, the mass ratio and the velocity ratio of a moving mass. Some experiments are conducted to verify the numerical results obtained. Experimental results for the dynamic responses of the test beam have a good agreement with numerical ones.

• 한국초지조사료학회지
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• 제10권1호
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• pp.21-26
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• 1990

This field experiment was carried out to determine the effects of nitrogen(N) application time (March 30, April 9 and April 19) and N fertilizer kind (urea and ammonium sulfate) in early spring on the grass growth, dry matter (DM) yield, crude protein (CP) content, CP yield (CPY), acid detergent fiber (ADF) content, DM digestibility (DMD) and N recovery in orchardgrass (Dactylis glomerata L.) meadow for soiling, 1989. The amount of N applied in early spring was 70 kg $ha^{-1}$, and non-fertilized plot was involved as control. In all fertilized plots the growth, DM yield, CP, CPY and regrowth yield of grasses were significantly increased compared with control. The best grass growth and DM yield were observed on March 30, and the best CP, CPY and N recovery were observed on April 9 among all fertilized plots. Also there were not significant differences between urea and ammonium sulfate fertilizer in grass growth, DM yield, CP, CPY, ADF, DMD and N recovery. In Suwon area, therefore, the optimum time of N application for soiling in early spring may be recommended early April, regardless of fertilizer kind of N.

• 한국초지조사료학회지
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• 제8권3호
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• pp.141-146
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• 1988

This field experiment was carried out to determine the effects of fertilizer application time in spring on the growth, crude protein (CP) content and dry matter (DM) yield of gasses for grazing Application times of fertilizer were on March 10, March 20, March 30, April 9 and April 19, and control (non-fertilized) plot was involved. All fertilized plots were also treated with single and compound fertilizer. The first harvesting date for grazing was on April 30, and the regrowth soiling yield was investigated on June 9, 1988. In all fertilized plots, the growth, DM yield, CP, CP yield and nigrogen recovery of grasses were significantly increased compared with control, especially on the plot of March 30. The regrowth yield on March 30, April 9 and April 19 were shghtly hig!!a than those of the others. And there were not significant differences of grass growth, CP content, and DM yield between single-and compound fertilizer treatment. On March 30 which was the best time of fertilizer application in spring, the accumulated temperature was 116.6^{\circ}C.$ and the subsoil temperature at 10 cm depth was 8.1 - 8.6^{\circ}C.$. Considering the average meteorological condition in Suwon area, the optimum application time of spring fertilizer for grazing may be recommended on March 30-April 3 (accumulated temp.; 100-125^{\circ}C.$, subsoil temp.; 8-9^{\circ}C.$).

• Journal of Plant Biology
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• 제20권3호
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• pp.127-134
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• 1977

In order to investigate the changes of free amino acids during the differentiation and development of young spike in naked barley, a typical spring grain, Wanju, and two winter grains, Sedohadaka and Nonsankwa No. 1-6 differing in their spring habits, were analyzed at different growth stages by thin layer chromatography. In all the varieties 22 ninhydrin positive components were detected at the sowing time of March 5 and 20 components in the sowing plots of March 30. In case of the latter plot, β-alanine was identified only in both Wanju and Sedohadaka, whereas pipecolic acid was detected only in Nonsankwa No. 1-6. Particularly, it is interesting that β-alanine was observed only in the case showing the normal heading independent of the varieties and sowing times. Whether these components are directly related to the physiology of spring habits in barley or not is also a question to be answered. Of the major amino acids, alanine and γ-aminobutyric acid were always detected in appreciably large spots, and serine, leucine, aspartic acid, valine and asparagine were somewhat larger. In the plot of march 30, glutamic acid was also detected in very large spot in both Wanju and Sedohadaka at the stage of spikelet differentiation and in Nonsankwa No. 1-6 at the stage of bract differentiation. Histidine, which showed the only qualitative difference among the varieties during seed germination, cannot be observed at all. Proline observed considerably large spot during seed germination was always detected but very small except that it was observed in large spot at the stage of floret differentiation in Nonsankwa No. 1-6 in the plot of March 5.

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1394-1398
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• 2000

This experiment was carried out to examine the seasonal changes in feed intake and feeding behavior in Korean spotted deer under farmed condition to obtain basic information for efficient feeding management. The seasonal daily gain was the highest (p<0.05) in summer and the lowest (p<0.05) in winter. Dry matter intake (DMI) was the highest (p<0.05) in spring (2,685 g/day) and the lowest in winter (1,929 g/day). Intake of roughage in the DMI was the greatest in spring and that in winter was significantly lower (p<0.05) than in spring. Also DMI, expressed in terms of metabolic body weight ($kgW^{0.75}$), was 85.5 g, 70.6 g, 70.9 g and 65.1 g for spring, summer, autumn and winter, respectively, and thus was the highest in spring and the lowest in winter (p<0.05). Deer exhibited similar eating patterns, comparatively short and frequent periods, in all seasons. They showed comparatively intensive patterns of rumination during midnight for autumn and winter and relatively continuous patterns of chewing activity during spring and summer. There were no significant differences in seasonal eating time and ruminating time. However, exercise time was the greatest for winter and the lowest for summer and there was a significant difference (p<0.05) between summer and winter. Although not significant, eating time per 100 gDM ingested tended to be short in spring and summer and long in autumn and winter. Ruminating time per 100 gDM ingested was the shortest (p<0.05) in spring compared with in other seasons. The conclusion can be drawn that since deer have seasonal differences in feed intake and feeding habits, it is necessary to establish and develop an efficient feeding system for deer.

• 한국임상수의학회지
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• 제12권1호
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• pp.887-896
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• 1995

In order to determine the efficacy of $Bayvarol^{(R)}$ strips(Bayer AG) against the mite Varroa jacobsoni and the safety of $Bayvarol^{(R)}$ strips in honey bees, a series of trials was carried out under field condition in autumn and spring. The results obtained were as follows; 1. The average varroacidal rate of $Bayvarol^{(R)}$ strips was 92.7% in autumn and 93.7% in spring. However the average varroacidal rats of treated control group was 73.8 % in autumn and 75.1 % in spring, and that of untreated control group was 12.1 % in autumn and 16.1 % in spring. 3. The average number of dead bees in $Bayvarol^{(R)}$ group was 13.0 in recommended dosage(RD), 12.3 in 2 times of RD and 14.0 in 4 times of 70 in autumn, and 19.7 in RD,17.0 in 2 times of RD and 19.0 in 4 times of RD in spring. However the average number of dead bees in treated control groups was 38.3 in RD, 62.7 in 2 times of RD and 60.3 in 4 times of RD in autumn and 18.0 in RD, 43.3 in 2 times of RD and 102 in 4 times of RD in spring and that of untreated control of group was 12.7 in autumn and 19.3 in spring. 3. The varroacidal effects and the number of dead bees of all groups were higher in spring than in autumn. 4. It was revealed that $Bayvarol^{(R)}$ were highly saft and effective varroacides for honey bees.