• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.251-257
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• 1998

This experiment was carried out to establish cutting propagation method of dendropanax morbifera $L_{EV}\$. at Wando in Chonnam, native area. The hardwood cutting and the greenwood cutting were able to be used as propagation method, but callus formation and rooting ratio in the greenwood cutting were higher than in hardwood cutting. The optimum cutting time was February to middle of March in hardwood cutting and July to August in greenwood cutting. The earthen-ball cutting method was better than normal cutting method in callus formation and rooting ratio. The rooting in different bed soils was the best at sand-loam soil. The application of IBA 100ppm promoted rooting.

• Geomechanics and Engineering
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• v.13 no.6
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• pp.977-995
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• 2017

It is well accepted that rock failure mechanism influence the cutting efficiency and determination of optimum cutting parameters. In this paper, an attempt was made to research the factors that affect the failure mechanism based on discrete element method (DEM). The influences of cutting depth, hydrostatic pressure, cutting velocity, back rake angle and joint set on failure mechanism in rock-cutting are researched by PFC2D. The results show that: the ductile failure occurs at shallow cutting depths, the brittle failure occurs as the depth of cut increases beyond a threshold value. The mean cutting forces have a linear related to the cutting depth if the cutting action is dominated by the ductile mode, however, the mean cutting forces are deviate from the linear relationship while the cutting action is dominated by the brittle mode. The failure mechanism changes from brittle mode with larger chips under atmospheric conditions, to ductile mode with crushed chips under hydrostatic conditions. As the cutting velocity increases, a grow number of micro-cracks are initiated around the cutter and the volume of the chipped fragmentation is decreasing correspondingly. The crack initiates and propagates parallel to the free surface with a smaller rake angle, but with the rake angle increases, the direction of crack initiation and propagation is changed to towards the intact rock. The existence of joint set have significant influence on crack initiation and propagation, it makes the crack prone to propagate along the joint.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.105-110
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• 1998

In this study, statistical and neural network methods were used to recognize the cutting tool states. This system employed the tool dynamometer and cutting force signals which are processed from the tool dynamometer sensor using linear discriminent function. To learn the necessary input/output mapping for turning operation diagnosis, the weights and thresholds of the neural network were adjusted according to the error back propagation method during off-line training. The cutting conditions, cutting force ratios and statistical values(standard deviation, coefficient of variation) attained from the cutting force signals were used as the inputs to the neural network. Through the suggested neural network a cutting tool states may be successfully diagnosed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.4
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• pp.428-433
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• 2015

A non-symmetric laser beam was used for cutting a thin glass substrate and its effect was investigated. In laser cutting of brittle materials, controlling crack initiation on the surface is crucial; however, it is difficult to ensure that crack propagation occurs according to a designed laser path. A lot of deviation in crack propagation, especially at the edge of the substrate, is usually observed. A non-symmetric laser beam generates a non-uniform energy distribution, which enhances directional crack propagation. A 20-W pulsed YAG laser was used for cutting a thin glass substrate. Parametric analysis was carried out and the crack control of the non-symmetric laser beam was improved. A theoretical model was presented and the limitations of the proposed process were also discussed.

• Korean Journal of Plant Resources
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• v.14 no.1
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• pp.53-59
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• 2001

This study was carried out to investigate mass propagation technique by using seed and vegetative propagation of Kalopanax pictus Nakai. For developing seed propagation, seed stratification and 1$0^{\circ}C$ after-ripening treatment induced embryo growth within 1 weeks, resulted in increasing germination rate of seeds up to more than 65% when planted. The softwood cutting using one year old shoot increased rooting rate to 69% whereas more than 1 year old shoot looked like inappropriate for cutting propagation. In the cutting timing, the rooting rate on June, 13 cutting of the first growth shoot was the highest, followed by June 20 and July 4. The most efficient cutting timing seemed to be the middle of June. When cutted shoots were soaked for 30 minute with IBA and NAA 1000mg.$L^{-1}$, rooting rate was increased above 70%. As the concentrations of plant hormone were increased above 2000mg.$L^{-1}$, the rooting rate was slowly decreased.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.11
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• pp.82-91
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• 1996

In this study, we put our object to carry out adaptive modeling of cutting process in turning system, and to find out the optimal cutting conditions to maximize material removal rate under some constraints. We used a back-propagation neural network to model the cutting process adaptively and a genetic algorithm to find out optimal cutting conditions. The experimental results show that a back-propagation neural network could model the cutting process effciently, and optimized cutting conditions for maximizing the material removal rate were obtained through the adaptive process model and genetic algorithms. Therefore, the proposed approach can be applied to the real machining system.

• Korean Journal of Medicinal Crop Science
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• v.28 no.5
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• pp.354-359
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• 2020

Background: The recent, decline in Black-berry Magnolia Vine (Schisandra repanda; BMV) native to Jeju Island, Korea, has raised concerns about the causes of this decline. We investigated the native environment of S. repanda and evaluated its propagation through cuttings to provide preliminary data for its restoration in Jeju Island. Methods and Results: The native environment of the BMV in the Hallasan National Park was surveyed and the climatic variables (temperature and humidity) were analyzed. The effects of the sex of the donor plant (male/female) type of cutting (softwood/hardwood), and treatment with a plant growth regulator (indole-3-butylic acid/rootone) on the rooting of BMV were investigated. Additinallly, the rooting rate, root count, and root length, as well as temperature and humidity were measured in the vinyl moist chambers. BMV was observed in 63 plants distributed from 567 m to 1,364 m above sea level of the Hallasan National Park. In the cutting experiment, the rooting rate was 71.9%, and it was higer in female plants (75.0%) than in male plants (68.8%). Conclusions: The mass propagation of BMV through cuttings valuable for its restoration as without such safeguard measures, the population could face extinction within a few decades.

• Korean Journal of Medicinal Crop Science
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• v.9 no.1
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• pp.55-61
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• 2001

In this study, effects of wiling peduncle on production yield and crude saponin content in Anemarrhena asphodeloides Bunge were investigation. The peduncle cutting were conduct on May 30, June 15, June 30, non-cutting of seed propagation type and young plant propagation type in Anemarrhena asphodeloides Bunge. The highest rhizome yield was 276.9g/plant on May 30, cutting puduncle in seed propagation type. The rhizome yield at seed propagation type was increased about 40.8%, compared to that at non-cutting. Crude saponin content in rhizome was 7.50% on May 30, cutting puduncle in seed propagation type. The crude saponin content at seed propagation type was increased about 32.2%, compared to that at non-cutting.

• Korean Journal of Plant Resources
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• v.36 no.4
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• pp.390-401
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• 2023

The purpose of this study was to identify the propagation characteristics of Diabelia spathulata (Siebold & Zucc.) Landrein through seeding and cutting methods. The seed germination rate was meager (0.22~3.56%). In hardwood cutting, the highest rooting rate was 36.1% in sand + perlite (2:1) and 37.8% in 1000 PPM of IBA pre-treatment. Softwood cutting showed the highest rooting rate when the cutting diameter was 3 to 5 mm and the cutting length was 7 to 8 cm. In particular, the highest rooting rate of 80% was observed in the sand among the 8 cultivation media treatments. In the case of root cuttings, the rooting rate was 83.3~96.7% in all cultivation media. The highest rooting rate was observed when the diameter of the cutting was 7 to 8 mm, and the length of the cutting was about 10 to 11 cm. Among cutting methods, root cutting showed the highest rooting rate. Division showed a 100% rooting rate regardless of size or growth status. For Diabelia spathulata (Siebold & Zucc.) Landrein, propagation by cuttings was more efficient than seeding. However, Further research on the morphophysiological dormancy and dormancy break of seeds is needed for seed propagation.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.200-204
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• 1999

Ligusticum chuanxiong has been an important oriental crude drug and cultivated for a long time in Korea. Ligusticum chuanxiong has been vegetatively propagating crop without seed due to its sterility and would be an allodiploid derived from the hybridization of two allied species. Generally, vegetative propagation is more costly per unit propagule than sexual(seedling) propagation. This study was conducted to find out the techniques of mass propagation by stem cutting for reduced seedling cost. When cutted on August 30 with 1st to 2nd internode, its highest rooting percentage was 81 percent. Rhizome yield of plants cutted in 50 percent on September 1 decreased to 9 percent less than control (rhizome propagation). Rooting percentage of rooted cutting plants after field planting on October 25 was the highest being 87 percent. Rhizome yield with planting appeared 127 and 120kg/10a on September 25 and October 25, respectively.