• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.1053-1057
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• 1996

The purpose of this study is to bring out the optimal design factors which effect on dynamic characteristics in the design of proportional flow control valve with fast response characteristics, and to verify the validity of the design factors In this study, force feedback type flow control valve with nozzle-flapper is studied. And, the influences which fixed orifice, nozzle diameter, and maximum displacement between nozzle and flapper effect on dynamic characteristics are analyzed. We have done simulations using the optimal design factors and simulink(Matlab) as a simulation tool, and verified the validity of our simulations by means of comparison our simulation results with an experimental results of another similar valve.

• Journal of Power System Engineering
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• v.15 no.5
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• pp.83-90
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• 2011

In general, 20-high Sendzimir mills(ZRM) use small diameter work rolls to provide massive rolling force. Because of small diameter of work rolls, steel strip has a complex shape mixed with quarter, edge and center waves. Especially when the shape of the strip is controlled automatically, the actuator saturation occurs. These problems affect the productivity and quality of products. In this paper, the problems in automatic shape control of ZRM were analyzed. In order to evaluate the problems for the automatic shape control in ZRM, recognition performance was analyzed by comparing the measured shape and the recognized shape. The actuator positions by the shape recognition and the manual operation were compared. From the analysis results, the necessity of the improvement of recognition performance in ZRM is suggested.

• Journal of Korean Society of Forest Science
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• v.3 no.1
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• pp.15-17
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• 1963

1) An experiment was made at the newly constructed glass house of Chun chan Agriculture callege to find out facts about the late-raising of Cortinellus edodes (Berk) Ido et Imai during the winter season. 2) The host timbers used in this experiment were Quercus Serrata Thumb and Quercus crispulo BI.; 5 years old each, the diameter ranging from 6cm to 17cm, dividing them into 12 diameter groups with 10 timbers in each group. The total number of timbess was 240 in two blocks. 3) As the pre-treatment of host timber, the autumn generation in 1962 was inhibited, and before being put into the glass-house, they were stimulated of generation for 3 days after 3 days, water-soaking. 4) The temperature control was made by using two coal stoves and the humidity control by spraying and two full water tanks. During cloudy weather and night, the green house was covered to preserue constant temperature of $5^{\circ}C{\sim}10^{\circ}C$. 5) The result; Quercus Serrata Thumb. with lesser diameter than 9cm showed no generation either in as big timber as one with diameter 11 cm. On the other hand, too big timbers showed low rate of generation; the reason, at a guess, is the too short period of cultivation and insufficient water soaking and inappropriate temperature. 6) The most standard size of host timber was found out be those with diameter 12cm~15cm in Quercus serrata Thumb, and those with diameter 14cm~17cm in Quercus crispula BI. Quercus crispula seemed to have slightly greater efficiency of generation than Quercus Serrata Thumb., but it could not be concluded as "decisive". Lastly, the host timber used in this experiment were old and the rate of generation was low as a whole.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.570-578
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• 2020

Rhizopus rot is a serious postharvest disease of various crops caused by Rhizopus spp. and controlled mainly by synthetic fungicides. We detected the antifungal activity of a culture extract of Setosphaeria rostrata F3736 against Rhizopus oryzae. The active ingredient was identified as moriniafungin, a known sordarin derivative, which showed minimum inhibitory concentrations of 1-8 ㎍/ml against Colletotrichum spp. and 0.03-0.13 ㎍/ml against Rhizopus spp. in vitro. Moriniafungin showed protective control efficacies against Rhizopus rot on apple and peach fruits. Treatment with 25 ㎍/ml moriniafungin delimited the lesion diameter significantly by 100% on R. oryzae-inoculated apple fruits compared with the non-treated control. Treatment with 0.04 ㎍/ml of moriniafungin reduced the lesion diameter significantly by 56.45%, and treatment with higher concentrations of 0.2-25 ㎍/ml reduced the lesion diameter by 70-90% on Rhizopus stolonifer var. stolonifer-inoculated peach fruit. These results suggest moriniafungin has potential as a control agent of postharvest diseases caused by Rhizopus spp.

• Korean Journal of Acupuncture
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• v.29 no.4
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• pp.634-642
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• 2012

Objectives : The aim of the study is to find out whether effect of acupuncture is depending on the diameter of needle, which is a possible component of dose of acupuncture needling. Methods : To compare acupuncture effects in different diameters of needle, we measured the changes in muscle fatigue recovery using surface electromyogram(sEMG) in healthy 8 volunteers. Muscle fatigue was induced by 20 times sit-up for 1 min. Immediately after induction of muscle fatigue, acupuncture needle was inserted into ST36 or ST25 for 10 min by diameters of 0.20 mm, 0.30 mm, or 0.40 mm needles. The sEMG recording was followed by acupuncture for 30 min. As a control group, sEMG was recorded for the same period at rest after muscle fatigue induction. Results : In both of ST 36 and ST 25, stimulation with 0.4 mm diameter needle showed significant rapid recovery followed by short period of muscle fatigue increase. Stimulation with 0.2 mm diameter significantly suppressed the increase of muscle fatigue. Conclusions : These data suggest that acupuncture effect is, at least in part, dependent on diameter of needle. Therefore, diameter of needle is also considered to achieve effective outcome of acupuncture.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.397-403
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• 2010

This study was conducted to investigate the changes in soil temperature, soil moisture content, light availability (photosynthetically active radiation, PAR) and diameter growth in 46-year-old Korean pine (Pinus koraiensis Siebold et Zuccarini) plantation located in Gwangneung experimental forest after 4 years from thinning. Three different thinning intensities [control, 45%(T45), and 60%(T60) basal area reduction] were applied in 2004. Mean soil temperature and soil water content were $8.9^{\circ}C$ and 14.3% for control, $10^{\circ}C$ and 16.1% for T45 and $10.2^{\circ}C$ and 16.1% for T60, respectively. Mean soil temperature and moisture content were significantly different among the treatment plots (p<0.05). Mean PAR in control, T45 and T60 was 44, 143 and178 ${\mu}mol/m^2$/sec, respectively and the differences were also statistically significant among the treatment plots (p<0.05). Mean annual diameter growth in control, T45 and T60 was 0.4, 1.5 and 1.2 mm, respectively. Diameter growth of Pinus koraiensis was steadily increased after thinning in comparison to control. Consequently, the results suggested that soil temperature, soil moisture content and light availability were likely to last beyond the 4 years after thinning in this Korean pine plantation.

• Journal of Korean Physical Therapy Science
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• v.10 no.2
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• pp.216-225
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• 2003

To demonstrate the effect of physical irritancy(massages) on the skeletal muscles of immobilization ddY mice models induced by right side sciatic nerve neurectomy, the cross sectional histological profiles of the muscularis (M) gastrocnemius, M. tibialis cranialis and M. tibialis caudalis were observed after 28 days of treatment of physical irritancy with the changes of body weight thickness of hind limb and individual muscle weights. In addition, changes of demonstrated with diameter of individual muscle fiber and muscle fasciculata, and number of muscle fiber in each of three types of muscles located in the calf. The massages were used in this study as physical irritancy. The experimental groups were divided into five groups, 1) Sham-operated group(Sham), 2) Neurectomized but not physical irritated control group(Control), 3) Neurectomized and physical irritated at knee pint regions(T1), 4) Neurectomized and physical irritated at calf regions(T2), and 5) Neurectomized and physical irritated at achilles tendon regions(T3). The experimental animals were used 5 per groups. The changes of number or diameter of muscle fiber in each muscles were calculated using automated image analyzer. The results are as follow : Thickness(diameter) of muscle fiber of M. gastrocnemius, M. tibialis cranialis and M. tibialis cranialis in right side of hind limb were remarkedly decreased in Control, T1, T2 and T3 groups compared to that of Sham group. However, the thickness was significantly increased in physical irritated groups compared to that of Control group in followed order : T3

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.139-143
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• 2011

This study was conducted to investigate correlation between external factors of chicory root and chicon fresh weight, whereby, to provide basic information of external yardstick of producing standardized chicon. For correlation between external factors (root diameter, root weight) of chicory root and chicon fresh weight were highly correlated. The relationship between external factors (root diameter, root weight) of chicory root and chicon fresh weight, root diameter was strongly affecting chicon fresh weight due to significant at its regression coefficient ($6.06^{***}$). In order to verity this correlation, the root diameter (x) of chicory that were 3 different varieties were based on the 4 different root diameter treatments, such as x ${\leq}$ 30 mm, 30 < x ${\leq}$ 40 mm, 40 < x ${\leq}$ 50 mm and x > 50 mm. The chicon production increased as root diameter increased and the chicon fresh weight, chicon width, and the number of leaves increased as well. Therefore, the measure of root diameter of chicory instead of the internal factors (carbohydrate, and so on.) can be used to predict the chicon fresh weight.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1598-1603
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• 2004

This paper is an experimental study on the performance characteristic with a variation of capillary diameter and length. The performance characteristic of a refrigeration system is predicted that it is occurring changes of flow pattern and pressure drop in a capillary tube because of reduction of capillary diameter 0.74 to 0.6 mm. The difference between experimental results and analytical results is mainly caused by values of friction factor for using to calculate pressure drop through a small diameter capillary tube under 0.74mm. The experimental equation is derived from capillary tube test data using curve fitting method.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.445-449
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• 2001

The objective of this study was to develop a new technique to control crown form of Hiscus syriacus to be used for an upright street tree with a single stem. Fertilization and raising the clear-bole length were the main treatments to compare the diameter and height growth of this species. The trees maintained with clear-bole length of 100, 150, and 200cm showed diameter growth of 15.7. 13.8, and 10.8mm, respectively, indicating the reduced diameter growth of trees with increasing clear-bole length, which is known as a typical characteristics in tending trees in silviculture. The effects of fertilization was not shown in this study. At the end of the two-year study from 1999 to 2,000, optimum diameter growth was obtained with the treatments of clear-bole length of 80-120cm, or 121-150cm. It is concluded that height and clear-bole length should be considered first in raising Hibiscus syriacus for street trees. Further study may be needed to obtain the effects of fertilization and raising the clear-bole length on uprightness of this species.