• Korean Journal of Organic Agriculture
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• v.17 no.2
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• pp.211-226
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• 2009

This experiment was conducted to investigate the effect of plant extracts, Chrysanthimum cinerariefolium and Melia azedarach to natural enemies and management of two spotted spider mite, Tetranychus urticae in organic strawberry fields in Jeonnam area. Plant extracts were highly toxic against Phytoseiulus persimilis, but low against Orius laevigatus. In the residual effect against Phytoseiulus persimilis, C. cinerariefolium showed lower level than M. azedarach which safe at least 1 day after spray. Emergence rates of parasitoids were about 40% at seven days after spray. Eretmocerus eremicus has very low emergence rate in treatment of M. azedarach, so it should release after spray of M. azedarach. To control of T. urticae C. cinerariefolium (CC) sprayed first and then sprayed C. cinerariefolium or M. azedarach (MA) for two and three times at a week interval. In the treatment of CC+MA and CC+CC+MA, the density of T. urticae was inhibited by 15th day but increased afterward. In CC+MA+CC, that of T. urticae inhibit from 8 days but also increased after I5th day. In case of spray M. azedarach (MA) first, the treatment of MA+CC, MA+MA+CC, MA+CC+MA suppressed T. urticae from the first day so the densy of T. urticae maintained low level to 30 days after spray. It suggested that M. azedarach should spray first and then alternative spray. When C. cinerariefolium sprayed before and behind to release of P. persimilis, the density of P. persimilis maintained unchanged but could not suppress T. urticae after 8 days which T. urticae increase time. When M. azedarach sprayed, the density of T. urticae rapidly decreased. It was accompanied with P. persimilis so T. urticae did not occur at 8 days after treatment.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.10
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• pp.873-878
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• 2016

SCM415 steel for the control valve undergoes wear because of continuous movement between the valve and valve case. The wear of the valve interrupts the performance of the valve, and decreases the service life. In this study, wear characteristics of the as-received and carburized SCM415 steels are evaluated. The wear tests are conducted for various temperatures and loads using a reciprocating wear tester. From these results, wear loss, specific wear rate, and coefficient of friction are analyzed. The wear mechanism was analyzed by SEM. The interaction effects between loads and temperatures on wear loss are determined for analysis of variance using MINITAB.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.1
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• pp.73-77
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• 1979

An artificial lodging was made at various growth stages of the soybean varieties Clark and KAS 100-3-1 to evaluate its effect on seed yield and other important agronomic characters. Results showed general increases in plant height and number of branches per plant whereas reductions in seed weight. number of nodes, pods and seeds per plant in the severly lodged plots. As compared to prevention of lodging, about 40 percent yield reduction was caused by the severe lodging treatrment. Furthermore, the most severe lodging before blooming resulted in about 66% yield loss.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.338-342
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• 2013

BACKGROUND: Two Field tests were conducted at Buan and Yangpyung in 2012 and 2013 to confirm controlling effect of mulberry popcorn disease and mulberry Sucker pests which are becoming serious in mass cultivation area of eco-friendly farming mulberry. METHODS AND RESULTS: As the treatments, 4 Natural products and 3 microbials were applied and 4 mulching materials were used. On the prevent effect of mulberry popcorn disease(Sclerotinia shiraiana) by using mulching materials, nonwoven fabric mulching showed worse effect than non-mulched treatment plot. Moreover, rice straw mulching showed significantly worse effect compare to nonwoven fabric and herb mulching treatments. Natural plant extracts and microbials showed 40~65% control value in 2013, which is little bit worse than 2012 results. On the control effect of mulberry Sucker(Amomoneura mori), organic products which combined with neem, sophora and derris showed excellent result as similar control level of Thiophanate-methyl. It means the chemical products can be replaced with organic product. CONCLUSION(S): According to the 2 years studied results, integrate eco-friendly farming measures are recommended for control of mulberry popcorn disease, because any single method is seemed not sufficient enough. However, natural plant extracts mixture is recommended as a product to control of mulberry Sucker.

• Journal of the Korean Data and Information Science Society
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• v.24 no.2
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• pp.303-310
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• 2013

Forty two female students whose fat mass ratio was over 30% were participated in the experiment of fat mass loss of two treatments for 8 weeks. They kept diary for foods they ate every day, took a picture of the foods, transmitted the picture to the experimenter by the camera phone. Among those, 28 students took the picture by regular camera phone (Treatment A), and the other students used smart phone (Treatment B). Fat mass weight and its related variables had been measured repeatedly four times at an interval of two weeks during 8 weeks. It was shown from mixed model analysis of repeated measurements data that AR(1) covariance matrix was selected as the optimal covariance matrix pattern. The correlation between two successive times is highly correlated as 0.838. Based upon the AR(1) covariance matrix structure, the students using smart phones were somewhat more effective in losing fat mass weight than the students using regular camera phones. The time effect was highly significant, but the treatment-time interaction effect was insignificant. The baseline effect and total cholesterol were found to be significant, but the calories with taking foods were somewhat significant, but the waist to hip ratio was found to be insignificant.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.373-382
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• 2005

This study was performed to investigate the effect of pork on the cadmium detoxification in rats. Ninety male Sprague-Dawley strains were divided into five stoups based on cadmium treatment(0, 25, 50, 100, 250 ppm) and cadmium intoxication was observed for 8 weeks. During following 8 weeks, casein was replaced by Pork and the effect of pork was compared with casein. During intoxicating, the growth mte was lessened. Feed efficiency ratio was significantly low, as cadmium intake was high Discontinuing cadmium feeding, the body weights were relieve4 Pork-fed groups seemed to have higher body weight than casein-fed groups. During intoxication, hemoglobin and hematocrit were dependent upon cadmium intake. However, they became normal at detocification stage. Cadmium accumulation of the pour-fed group was lower than that of casein. Especially, the factors which affected the cadmium content in kidney were Cd(p<0.001) and $Cd^*pork(p<0.001)$. Metallothionein(MT) was increased with cadmium, and MT was not likely to be affected by pork. This study may provide scientific background of pork for detoxification from heavy metals such as cadmium.

• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.535-543
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• 2013

The objective of this study was to analyse the residual stress in Larix kaempferi board during and after kiln-drying. The boards were primarily intended for using as laminar of cross laminated timber (CLT). In this study, the equivalence of moisture content by equalizing treatment was proved and reduction of residual stress by conditioning treatment was quantified. Prong test and slice test were carried out to analyse the residual stress in wood during drying. Transverse casehardening was measured immediately after making prong sample. Residual stress of four parts in wood from surface to center was analyzed quantitatively based on elastic deformation after just cutting slices from board. Tensile stress and compressive stress on the surface of board during drying did not exceed 2.2 MPa when boards were dried by kiln-drying schedule of T10-C4 and T12-D5. Because the tensile strength and compressive strength of transverse direction of Larix kaempferi lumber are 2.65 MPa and 4.60 MPa, application of more severe drying schedule can be recommended. Cup and twist were reduced by about 40% by equalizing and conditioning treatments after drying.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.344-349
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• 1981

This study was conducted to define the effect of 2.4-D, NAA, Benzyladenine, and basic mediums on the callus induction and the organ differentiation from the meristem tips and the stem and leaf segments of the potato. Benzyladenine promoted the induction and growth of shoot from the meristem tip of potato but inhibited initiation of roots and induction of callus. At higher concentration of NAA than 0.5 ppm and of 2.4-D than 1.0 ppm the shoots were not initiated but the callus was induced from the meristem. The callus growth was significantly promoted on the medium containing NAA than 2.4-0. The initiation and growth of the shoots from the potato meristem was significantly increased in the medium containing 2.4-D and BA, or NAA and BA, compared with those containing BA, NAA or 2.4-D alone. The callus was more easily induced from the stem segments than the leaf segments of potato. And the 2.4-D was more effective for the induction and growth of the callus than the NAA. MS medium diluted its concentration to 1/2 was more suitable for the initiation and growth of the shoots from the potato meristem than the MS standard medium. For the initiation and growth of the shoots from the potato meristem, the most desirable medium was the diluted MS medium containing 1.0 ppm BA and 0.1 ppm NAA or 0.1 ppm 2.4-D.

• Restorative Dentistry and Endodontics
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• v.34 no.5
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• pp.406-414
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• 2009

The purpose of this study was to examine the effect of hydrogen peroxide at different application time and concentrations on the microtensile bond strength of resin restorations to the deep and the pulp chamber dentin. A conventional endodontic access cavity was prepared in each tooth, and then the teeth were randomly divided into 1 control group and 4 experimental groups as follows: Group 1, non treated; Group 2, with 20% Hydrogen peroxide ($H_2O_2$); Group 3, with 10% $H_2O_2$; Group 4, with 5% $H_2O_2$; Group 5, with 2.5% $H_2O_2$; the teeth of all groups except group 1 were treated for 20, 10, and 5min. The treated teeth were filled using a Superbond C&B (Sun medical Co., Shiga, Japan). Thereafter, the specimens were stored in distilled water at $37^{\circ}C$ for 24-hours and then sectioned into the deep and the chamber dentin. The microtensile bond strength values of each group were analyzed by 3-way ANOVA and Tukey post hoc test(p < 0.05). In this study, the microtensile bond strength of the deep dentin (D1) was significantly greater than that of the pulp chamber dentin (D2) in the all groups tested. The average of microtensile bond strength was decreased as the concentration and the application time of $H_2O_2$ were increased. Analysis showed significant correlation effect not only between the depth of the dentin and the concentration of $H_2O_2$ but also between the concentration of H202 and the application time(p < 0.05), while no significant difference existed among these three variables(p > 0.05). The higher $H_2O_2$ concentration, the more opened dentinal tubules under a scanning electron microscope(SEM) examination.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.2
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• pp.72-80
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• 2019

Purpose: The purpose of this study is to compare and analyze the shear bond strength and fracture pattern in different enamel tooth surface treatments for resin splinting materials. Materials and Methods: G-FIX and LightFix were used as tooth splinting materials. Twenty bovine mandibular incisors were used for the preparation of the specimens. The exposed enamel surface was separated into four parts. Each tooth was treated with 37% phosphoric acid, 37% phosphoric acid + adhesive resin, 37% phosphoric acid + G-premio bond, and G-premio bond for each fraction. Shear bond strength was measured using a universal testing machine. After measuring the shear bond strength, the fractured surface of the specimen was magnified with a microscope to observe the fracture pattern. Two-way ANOVA was used to verify the interaction between the material and the surface treatment method. One-way ANOVA was used for comparison between the surface treatment methods of each material and post-hoc test was conducted with Scheffe's test. An independent t-test was conducted to compare shear bond strengths between materials in each surface treatment method. All statistics were conducted at 95% significance level. Results: G-FIX, a tooth splinting resin, showed similar shear bonding strength when additional adhesive resins were used when material was applied after only acid etching, and LightFix showed the highest shear bonding strength when additional adhesive resins were used after the acid etching. In addition, both G-FIX and LightFix showed the lowest shear bond strength when only self-etching adhesive was applied without additional acid etching. Verification of interactions observed interconnection between resins and surface treatment methods. Most of the mixed failure was observed in all counties. Conclusion: When using G-FIX and LightFix, which are tooth-splinting materials, it is considered that sufficient adhesion will be achieved even after applying only acid etching as instructed by the manufacturer.