• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.285-290
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• 1996

This experiment was conducted to investigate the variation of adhering primary and secondary rachis branches of panicle in three ecotypes at National Honam Agricultural Experiment Station in 1993. Three ecotypes. Odaebyeo and Sinunbongbyeo as early-maturing type, Cheongmyeongbyeo and Changanbyeo as medium, and Dongjinbyeo and Mangeumbyeo as late-maturing type were used. The treatment were 5 planting times from May 5 to 5 July by 15 day intervals. The number of primary rachis branch in early maturing type recorded high in between May 5 and 20 May as early transplanting. Medium and late-maturing type, however, was found to be have more primary rachis branches at the late time of June 20 transplanting than at the optimum transplanting of Honam area. The number of secondary rachis branch was high between June 5 and 20 June regardless ecotypes. The rate of secondary rachis branch per primary rachis branch was increased with later transplanting time up to June 5, but showed no differences onwards. The number of grain in primary and secondary rachis branches were low in transplanting time of May 5 regardless ecotype but high in late transplanting time by July 5. Densinty of seed sets was found to be higher in late transplanting than in early transplating;early-maturing type showed high in July 5 and 20 June in medium-late maturing type respectively.

• Journal of the Korean Wood Science and Technology
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• v.17 no.1
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• pp.3-11
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• 1989

This study was carried out to investigate the physical and mechanical properties. durability of adhesive bond and paint film for the basic data which were required to determine the suitability as a raw material for furniture the laminated veneer lumber (LVL) with pitch pine (Pinus rigida Mill). The results obtained were as follows; 1) The proper pressing time for making the LVL was over 45 second per milimeter of LVL thickness. 2) The bending strength of the LVL was lower than that of the solid wood but the compressive strength of the LVL was similar to that of the solid wood. The strength increased with the decrease of veneer thickness. 3) The impact bending absorbed energy of the LVL was 0 to 0.3 kg.m/$cm^2$ in the direction of parallel to the grain. The energy of the LVL was lower than that of the solid wood (0.68 kg.m/$cm^2$). 4) In warm water soaking and cold-dry tests, delamination of adhered layers surface crack, swelling, and color change were not found when the hot pressing time was over 45 second per milimeter of LVL thickness. As a result of soak under vacuum test shrinkage in the direction of parallel to the grain was about -1.0 percent and. was about 3.0 percent in the direction of the perpendicular to the grain. 6) The film cacks on the LVL's surface after the wet and cold-dry test were not found at all. 7) In the use of the LVL for interior decoration it was considered that the surface of the LVL be overlaid crossly with fancy veneers of birch and paulownia, etc. This cross overlayirg methods have resulted in few cracks on the fancy veneer.

• Journal of Korean Society of Forest Science
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• v.55 no.1
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• pp.68-75
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• 1982

This study was carried out to promote percent survival of the walnut seedling grafting. The hardwood scions of the walnut were grafted on the nures seed-stock of the Juglans mandshurica Mat in an electric heating bed, then planted in field. The results obtained from the study were as follows : The optimum time of scion cpllection was from January to February. The best medium of the seed bed was sandy soil. The best grafting time was form the early to the 20the of the march. When the grafted seedling in the heating bed was trans-planted on filed 90percent of the seedlings was survived until autmn. The percent grafting on the elective heating bed was 90%. Crown gall occuring frequently in chestnut nurse graft was not appeared in juglans mandshurica Max grafted seedling of after outplanting. The grafted seedlings have not shown any physiological defects but developed normaly 3 years since grafting.

• Journal of Korean Orthopaedic Sports Medicine
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• v.4 no.2
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• pp.122-127
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• 2005

Purpose: To study the mechanism of injuries or discomfort during kendo and to analyze the causes of injury, injured parts of body, treatments modalities, and degree of return to the pre-injury activity level. Materials and Methods: We studied ninety-eight kendo players who had played at three gymnasium of Korean Kumdo Association, were older than high-school age, had been playing kendo for more than six months, and had any pain or discomfort after playing kendo. We analyzed the questionnaire and interviewed the patients concerning the injured parts of body, symptoms, treatments. Results; The mean age was 30.2 years old, and the onset of symptoms was between two weeks and six months after starting the kendo. Many of them were injured during attacking(32.2%). The injuries of feet were increased on players who exercised for less than 1 year. Only fifty-nine players(60.2%) were treated within one month. Among them, thirty-eight percent were treated by oriental medicine or other departments and only thirty-six percent were treated by orthopaedic surgeons. The prevalence of injuries of the foot and ankle was highest(38.8%), and there were the wrist(13.1%), shoulder(11.9%), knee(11.9%) in order of prevalence. Fifty percents of them could return to the pre-injury activity level. Conclusion: The prevalence of injuries of the foot and ankle was highest(38.8%), and were increased on players who exercised for less than 1 year. Sixty percents of players were treated with any proper modalities, and only thirty-six percent were treated by orthopaedic surgeons.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.230-235
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• 2015

The experiment was conducted to elucidate the growth characteristics of sorghum in the different planting methods: direct sowing and transplanting (20 days after sowing, DAS). Weed weight was taken from three randomly chosen-2 plots 60 DAS (DAT). One time (20, 30 days after transplanting, DAT) and two times (10/20, 10/30, 20/30, 20/40 DAS) application of weeder machine (FRT 80E) were conducted for direct sowing and transplanting, respectively. In transplanting, the weed control efficacy of weeder machine at 90 DAT was about 67% (DAT 20), 57% (DAT 30) at one time and 87% at two times. The most effective application number was two times (20/40 DAT) followed by one time (20 DAT). However, when reviewing yield and economy, the frequency and times of using weeder machine were preferably one time and 20 DAT. Results with mechanical weed control have been particularly good in transplanted row crops such as sorghum. In direct sowing, the weed control efficacy of weeder machine 60 DAS was about 87% (10/20 DAS), 88% (10/30 DAS) and 82% (20/30 DAS) at two times, respectively. When reviewing yield and economy, the times and frequency of weeder machine were preferably two times, 10 and 30 DAS.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.22-24
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• 1974

1. Object and importance of the research. The exports of plywood are increasing annually and it has ranked first in the world market because of the high quality product developed and manufactured using modern techniques. However, it is known that the exports of the other wood products, except plywood, is inactive because of their low quality. Accordingly, to increase the exports of various wood products investigations were carried out on kiln drying techniques to improve the quality of the wood. 2. The details and scope of the research Wet wood should be kiln dried before use to prevent various drying defects such as distortion, shrinkage etc, which would develop after processing, and also wet wood is not suitable for cutting, gluing and finishing. Therefore, the kiln drying properties of lumber from such species as Persimmon, Oak, Ramin and Meranti which are used in large quantity for manufacturing exporting wood products have been studied. Also the real state of kiln drying industry in Korea was investigated. 3. Results and proposal for practical use of the research 3. 1 Results of the research 3.1.1 The end checks and the time for drying from intial moisture content of about 40 percent to 5 percent moisture content in ovendry were investigated as Table 1. 3.1.2 The kiln dried results, for 30mm stock, which are presented by using kiln schedule Table 2 are as Table 3. 3.1.3 The kiln schedule for Persimmon which has a normal drying properties is given in Table 4. However, the persimmon which has easy checking properties should be air dried under a relative humidity of above 85% until reaching about 25 percent moisture content. 3.1.4 The kiln schedules for ramin, meranti and oak are given respectively as follows. Ramin kiln schedule ............ Table 5 and Table 6 Meranti kiln schedule ............ Table 7 Oak kiln schedule ............ Table 8 3.2 Proposal for practical use of the research Firms using the above species should be informed the results of the research so they can be used to preventing drying defects and shortening drying time.

• Korean Journal of Heritage: History & Science
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• v.52 no.4
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• pp.38-55
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• 2019

At Otani University in Kyoto, Japan, there is a rubbed copy of Tripitaka Koreana, presumably printed in 1381. According to the postscript of the copy, written by Saek Lee himself, the rubbed copy was made at Haeinsa temple in 1381 and was kept at Sinluksa temple in Yeuju. The copy was delivered as a gift to Japan in 1414 and now is kept at the Library of Otani University. Although an approximate summary of the content of the copy was reported in the early 2000s after a basic survey, details of the copy, including the concrete format and packaging paper, are not known yet. In this paper a detailed survey of the copy is conducted on the 109 pages. The copy is divided into two parts: the wrapping and the inner pages. The wrapping paper is divided into yellow and brown colors depending on the material of the paper. The yellow colorwrapping paper was possibly made in 1381 at the time of the rubbed printing, and the brown wrapping paper was repaired after being moved to Japan. Using funds collected in February 1380, the copy of Gyeong(經), Yul(律), and Ron(論) chapters was printed in April 1381. Binding of the copy was completed in September, and the wrapping paper with the title in gold was made in October 1380. The box for keeping Buddhist scriptures was manufactured in November 1380. The copy was moved to Sinluksa temple in April 1382 and delivered to Japan in 1414. At Otani University, the copy is stored in separate rectangular boxes 32.1×25.3cm in size with a height of 23.6cm. The rectangular plate on the four sides is red in external color but black colorinside. The box for keeping Buddhist scriptures was probably made in 1381, but a partial repair was made later. Because of the difficulty of executing a detailed survey of the box for Buddhist scriptures, it is hard to find out its nation and period of production. We look forward to studying the copy as well as the box for Buddhist scriptures in future.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.52-56
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• 1985

For the fundamental studies of radiation breeding in edible marine algae, the biological effects on conchospores of Porphyra species by gamma-irradiation were examined. Two varieties, Keun-cham-gim (Porphyra tenera Kjell. form tamatsuensis Miura) and Saga No.5, were chosen for this study, and their conchospores after r-irradiation($5.0{\sim}20.0$ KR) were cultured for 50 days. The results obtained were summarized as follows. 1. Gamma-irradiation in less than the dose of 20KR did not affect germination of conchospores, and almost all spores grew into two cells germ in 24 hours after irradiation, but withering germs were gradually increased in number according to higher exposure within 5 days old culture. 2. High irradiation caused the induction of giant cells, abnormal useless growth of hold-fast, lumpish thalli and callus-like lumpy tissues. 3. The liberation of neutral spores from young germs and carpospores from mature thalli were observed on the frond exposed at $10{\sim}20$ KR irradiation. All spores were normal in division and its size. 4. The best irradiation effect on growth of Keun-cham-gim was observed at 10 KR dose, whose growth-rates were $140\%$ in wet weight and $108\%$ in mean frond area, but only $48\%$ was recorded in wet weight at 20 KR exposure. Saga No.5 were in contrast with Keun-cham-gim, and their most growth-rate was $400\%$ in wet weight ($258\%$ in frond area) at 10 KR irradiation and the worst was $20\%$ at the dose of 20 KR. 5. The withering phenomenon to death by treatment of gamma-ray presented substantial difference between two varieties. Survival rate compared with control in Keun-cham-gim was $70.7\%$ at 20 KR, but that in Saga No.5 recorded $47.0\%$ at same dose. 6. Synthesizing the results of high and low r-irradiation, it was suggested tat high r-irradiation in more than 5.0 KR inhibited conspicuously the growth of germs derived from conchospores, and about half of them withered at 15.0 KR dose or more.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.6
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• pp.1731-1741
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• 2014

Recently, many overpasses, highway, and advanced transit systems have been constructed to distribute the traffic congestion, thus small size of curved bridges with small curvature such as ramp structures have been increasing. Many of early curved bridges had been constructed by using straight beams with curved slabs, but curved steel beams have replaced them due to the cost, aesthetic and the advantage in building the section form and manipulating the curvature of beams, thereby large portion of curved bridges were applied with steel box girders. However, steel box girder bridges needs comparatively high initial costs and continuous maintenance such as repainting, which is the one of the reason for increasing the cost. Moreover, I-type steel plate girder which is being studied by many researchers recently, seem to have problems in stability due to the low torsional stiffness, resulting from the section characteristics with thin plate used for web and open section forms. Therefore, in recent studies, researchers have proposed curved precast PSC girders with low cost and could secured safety which could replace the curved steel girder type bridges. Hence, this study developed a Smart Mold system to manufacture efficient curved precast PSC girders. And by using this mold system a 40 m 2-girder bridge was constructed for a static flexural test, to evaluate the safety and performance under ultimate load. At the manufacturing stage, each single girder showed problems in the stability due to the torsional moment, but after the girders were connected by cross beams and decks, the bridge successfully distributed the stress, thereby the stability was confirmed. The static loading test results show that the initial crack was observed at 1,400 kN when the design load was 450 kN, and the load at the allowable deflection by code was 1,800 kN, which shows that the safety and usability of the curved precast PSC bridge manufactured by Smart Mold system is secured.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.7-13
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• 1994

This study was conducted to investigate the relationships between yearly variations of climatic factors and yearly variations of productivity in Alisma plantago L. In addition, correlation coefficients among yield and yield components were estimated. The data of yield and yield components were collected from the Statistical Year Book of Seungju province, Reserach Report of Seungju Extension Station of Rural Development Administration, and farmers for 10 years from 1983 to 1992. The meteorological data gathered at the Seungju Weather Station for the same period were used to find out the relationships between climatic factors and productivity. Yearly variation of the amount of precipitation in October and the minimum temperature in November were large with coefficients of variation(C.V.) of 106.44, 144.08%, respectively, but the variation of the average temperature, maximum temperature, minimum temperature from July to September were relatively small. Fresh weight and dry weight of roots vary greatly with C. V. of 30.62, 31.85%, respectivly. Plant height and stem length show more or less small C. V. of 5.51, 6. 26%, respectively and leaf width, leaf length, number of stems and root diameter show still less variation. Correlation coefficients between maximum temperature in November and plant height, stem diamter, number of stems, root diamter and dry weight of roots are positively significant at the 5% level. There are high signficant positive correlations observed, between yield and yield components. The maximum temperature would be used as a predictive variable for the estimation of dry weight of roots and number of stems. Simple linear regression equations by the least square method are estimated for number of stems $(Y_1)$ and the maximum temperature in November(X) as $Y_1=4.7114+0.5333\;X\;(R^2=0.4410)$, and for dry weight of roots$(Y_2)$ and the maximum temperature in November(X) as $Y_2=55.0405+14.3233\;X\;(R^2=0.4511)$