• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.96-102
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• 2011

The objective of study was carried out to find a proper entrance date for breaking dormancy depending on cutting and entrance date into greenhouse investigating plant growth and flowering characteristics of chrysanthemum 'Baekma'. Days to visible bud formation and days to flowering were increased as cutting date was delayed. The flowering rate of cutting on September 18 was 100% while cutting on October 30 did not induce flower bud formation. Flower characteristics were surveyed after 'Baekma' and 'Jinba' rooted cuttings were planted on September 10. Branching formation rate of 'Baekma' was gradually increased as entrance date was delayed while that of 'Jinba' was about 70-80% regardless of entrance date. Lethality of 'Baekma' moving into greenhouse on December 20 was 1.5% by cold injury. 'Jinba' started to die on November 10 by cold injury and lethality of 'Jinba' moving into greenhouse on December 20 was 21.7%. Thus, lethality of 'Jinba' was about 5-14 times higher than that of 'Baekma'. Days to visible bud formation and days to flowering were decreased as entrance date was delayed in chrysanthemum 'Baekma'. Days to visible bud formation of entrance date on November 10 and December 10 were 67.9 and 50.3, respectively. On the other hand, that of 'Jinba' was increased until entrance date on December 10 and decreased on December 20. Based on these results, it was suggested that dormancy of 'Baekma' was started at late September and completed at late October.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.2
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• pp.85-94
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• 1994

The cutting mechanism of ultrasonic vibration machining is characterized as two phases, that is, an impact at the cutting edge and a reduction of cutting force due to non-contact interval between tool and workpiece. In this paper, in order to identify cutting dynamics of a system with ultrasonically vibrated cutting tool, an ARMA modeling is performed on experimental cutting force signals which have a dominant effect on cutting dynamics. The aim of this study is, through Dynamic Date System methodology, to find the inherent characteristics of an ultrasonic vibration cutting process by considering natural frequency and damping coefficient. Surface roughness and stability of cutting process under ultrasonic vibration are also considered

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.353-358
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• 2012

This study was conducted to enhance the propagation of Acanthopanax divaricatus and Acanthopanax koreanum through different cutting practices. For propagation by cuttings, scions were taken on September 1. This already has hard skin and showed much higher values in terms of root length, root number, rooting ratio and root weight than those taken on June 30 and August 1. Regardless of cutting date, 50% shading resulted to the highest root length, root number, root ratio and root weight. Meanwhile, 95% shading significantly reduced these parameters compared with no shading. These results suggest that over-shading may inhibit root growth. Two growth regulators, IBA (concentration of 1,000, 2,000, 3,000 ppm) and Rootone-F (0.4%) were also tested of its effect to the cuttings. Rootone-F was found to be more effective than IBA. Cutting treated with Rootone-F had slightly higher root length and root number. A. koreanum which grows well in hot climatic condition showed better rooting ability than A. divaricatus.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.2
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• pp.84-90
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• 1986

This experiment was carried out to evaluate the effect of cutting frequency and the last cutting date on the dry matter yield, the initial characteristics of spring growth, the yield of the first crops after winter, crude protein and crude fiber yield and the correlation efficients among the above items in timothy-dominated award. Cutting frequency was scheduled by 2, 3 and 4 times a year as main plot and the last cutting date in autumm were sept. 30, Oct. 10 and Oct. 20 as subplot. Experiment was arranged as a split-plot design with three replications and was performed for 4 years from 1980 to 1983 at the alpine area. The results obtained are summarized as follows: 1. The start of spring growth was somehow early as cutting frequency increased but not significant, and was not influenced by the last cutting data. 2. The dry matter yield was decreased by cutting frequency, but was not affected by the last cutting data. 3. The dry matter yield of the first crops after winter significantly decreased by cutting frequency, but failed to show and significant differences by the last cutting date. 4. Crude protein yield was increased by cutting frequency, while dry matter percentage was decreased. Crude fiber yield did not show the same trends. 5. There was a significant positive correlation between DM yield and DM percentage and yield of the first crops after winter, and between DM percentage and yield of the first crops after winter. However, there was a significant negative correlation between crude protein yield and DM percentage and yield of the first crops after winter. 6. It may be concluded from the above results that three times as cutting frequency and Sept. 30 as the last cutting data were desirable for the DM yield, but four times as cutting frequency and Sept. 30 as the last cutting data for the crude protein yield.

• Journal of Sericultural and Entomological Science
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• v.19 no.1
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• pp.37-38
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• 1977

Since 1972 a series of experiments were conducted to reveal physiological function and biological activities involved in rooting of mulberry cuttings, and the behaviour of ether extractable growth control substances in leaves and stens. Measurements were made on various mulberry varieties for respiration of cuttings, suitable size for the production of cuttings, change of rootability of cuttings with growth of cutting shoots after cutting date, rooting tests on the green beans with ether leaf extract and ether stem extract, and rooting effect of cutting by NAA treatment. (omitted)

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.1-10
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• 2005

Tree-ring chronologies can be used to date historical buildings or furnitures by matching them with chronologies of living trees. Tree-ring dating gives a calendar year to each tree ring and produces the cutting dates of logs or woods. In this study, we intend to extend our tree-ring dating applications to Korean furnitures. As a case study, we examined two traditional furnitures, one cabinet 'Jang' and the other chest, 'Bandaji'. The cutting date of the cabinet woods was A.D. 1839. The date of the outmost ring in the chest was A.D. 1904. Due to no bark present, the cutting date of the chest was only estimated as $1930{\pm}10$ by 'sapwood rings' estimation method. Ring-width pattern of the latter one also indicated that the origin of the chest must be Kangwon province. This case study suggests that tree-ring dating would be a useful and accurate method to identify the critical dates for the chronicles of Korean traditional furnitures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.483-488
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• 1997

This experiment was conducted to determine cutting time on the yield and nutritive value of brittle culm rice. Plant height and number of tiller were significantly different between variety and cutting time, and regrowth plant height and rate of regrowth tiller were tall and high at the early cutting. Early cutting increased crude protein, fat and NFE(Nitrogen free extract) content in the harvested foliage but crude fiber and ash content were decreased in the first cutting. Those of second cutting also showed reverse tendency. Fresh and dry matter yield were highest on heading date cutting, and those of KL501 were higher than those of Seomjinbyeo. TDN(Total digestible nutrients) content was higher with earlier cutting for initiated cutting, but that of second cutting was reversed. KL501 showed higher TDN content than Seomjinbyeo did at the any cutting time. TDN yield of heading date cutting was higher than that of the other cutting time.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.3
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• pp.55-60
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• 2008

Until a recent date, the surface finish generated in turning by the conventional cutting tool is directly related to the feed rate and the size of the tool nose radius. With this tool a large feed rate will give poorer surface finish and a large nose radius will generate a better surface finish. Recently a new concept in the tool design is introduced to achieve a better surface finish at a higher feed rate. This is the wiper tool, which has the portion of nose with infinite radius. This can remove the ridges left when the conventional tool is used. In this study two series of cutting tests with the wiper tool and the conventional tool are carried out under the various cutting conditions of cutting depth, feed rate and cutting speed. The effects of the wiper design and the cutting conditions on the surface roughness resulted are carefully examined and compared.

• Journal of Mechanical Science and Technology
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• v.18 no.5
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• pp.753-761
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• 2004

In this paper, an efficient method for generating 5-axis cutting data for a turbine blade is presented. The interference elimination of 5-axis cutting currently is very complicated, and it takes up a lot of time. The proposed method can generate an interference-free tool path, within an allowance range. Generating the cutting data just point to the cutting process and using it to obtain NC data by calculating the feed rate, allows us to maintain the proper feed rate of the 5-axis machine. This paper includes the algorithms for: (1) CL data generation by detecting an interference-free heel angle, (2) finding the optimal tool path interval considering the cusp-height, (3) finding the adaptive feed rate values for each cutter path, and (4) the inverse kinematics depending on the structure of the 5-axis machine, for generating the NC data.

• Korean Journal of Plant Resources
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• v.33 no.5
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• pp.436-445
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• 2020

Goji berry (Lycium chinense Mill.) is one of medicinal plants. Its leaves has been used to manufacture the functional foods by replacing the dried-fruit because of low production costs. In order to produce the leaves of uniform quality, continuous selection and the establishment of cultivation techniques were required. Among the eleven recommended cultivars, 'Myeongan' showed high yielding and rapid regeneration after cutting. The dried-leaf yield was linearly increased from 106 kg/10a on May 16 to 287 kg/10a on June 20. An appropriate cutting date and cutting length (about 60-70 cm) was important factors for its efficient regeneration. The late cutting times were not suitable due to difficulties during plant harvesting because of stem rigidity and thorn generation. The betaine content of leaves ranged from 1.43 ~ 2.63% and significantly affected by the varieties and the cutting dates. The main physiological functionality of leaf was Angiotesin-1-converting enzyme (ACE) inhibitory activity, representing the anti-hypertensive. The other physiological functionalities, XOD inhibitory activity, antioxidant activity, tyrosinase inhibitory activity, SOD-like activity, α-glucosidase inhibitory activity and fibrinolytic activity, were not detected or less than 20%.