• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.219-226
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• 2006

The wastes (the needle leaves and branches) produced from thinning the forest were fermented under an anaerobic condition (pine silage) to utilize as a forage source of ruminants. An in situ trial was conducted with two ruminally fistulated Korean native cows by 4 replicates (2 bags per cow), and in vivo digestibility of pine silage was estimated with five Korean native steers by 5 replicates in incomplete double turn-over design. In order to investigate feed efficiency and carcass traits, forty eight Korean native bulls were assigned to four treatments (0%, 25%, 50%, 75% of pine silage) with a completely randomized design in 12 pens accommodating 4 animals per pen. The amounts of concentrate and roughage allowed to experimental animals were in the range of 2.5% and 0.6% of body weight, respectively. Animals had freely accessed to mineral block and water in stanchion barn.An in situ crude protein digestibility of the roughage sources when suspended for 48 hrs in the rumen was higher for feeding the pine silage than the rice straw, whereas NDF digestibility was vice versa. No differences between the treatments were observed in in vivo digestibilities of dry matter, crude protein and NDF. Daily body weight gain was significantly (P<0.01) higher for the pine silage substitutions compared with the rice straw feeding except for the 25% silage feeding. The pine silage feeding did not affect feed efficiency.In carcass traits, marbling score tended to be higher for the 50% pine silage treatment than the other treatments while back fat thickness tended to be the thinnest for the rice straw feeding. From these results, it may be recommended to substitute pine silage, as a forage source, for rice straw by 50 percent.

• Restorative Dentistry and Endodontics
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• v.36 no.5
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• pp.409-418
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• 2011

Objectives: The purpose of this study was to compare the microshear bond strength (${\mu}$SBS) and bonding interfaces of two-step total-etching and self-etching adhesive systems to three etch types of dentin either the acid etched, laser etched or laser and acid etched. Materials and Methods: The occlusal dentinal surfaces of thirty human molars were used. They were divided into six groups: group 1, 37% $H_3PO_4$ + Single Bond 2 (3M ESPE); group 2, Er:YAG laser (KEY Laser 3, KaVo) + Single Bond 2; group 3, Er:YAG laser + 37% $H_3PO_4$ + Single Bond 2; group 4, Clearfil SE Primer + Bond (Kuraray); group 5, Er:YAG laser + Clearfil SE Bond; group 6, Er:YAG laser + Clearfil SE Primer + Bond. The samples were subjected to ${\mu}$SBS testing 24 hr after bonding. Also scanning microscopic evaluations were made on the resin-dentin interfaces of six specimens. Results: The ${\mu}$SBS of group 2 was significantly lower than that of groups 1 and 3 in Single Bond 2 (p < 0.05). There were significant differences among the uSBS of groups 4, 5, and 6 in Clearfil SE Bond (p < 0.05). Very short and slender resin tags were observed in groups 2 and 5. Long and slender resin tags and lateral branches of tags were observed in groups 3 and 6. Conclusions: Treatment of dentin surface using phosphoric acid or self-etching primer improved the adhesion of Er:YAG lased dentin.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.1
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• pp.45-52
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• 2020

This study analyzed the components contained in the pine needles of first and second-year-olds to analyze the factors that the in vivo content of inorganic elements affects the sex determination of pine trees. In response, the plan for pine tree plant and maintenance was intended to be presented in consideration of the reproductive environment and physiological characteristics. The results are as follows. First, last year, when there were many encyclopedias, the analyzed N(%) content was found to be high. The nitrogen content of the previous year's soil was found to affect the production of the spheres the following year. This is believed to be possible to reduce the rate of Pine pollen produced in the new plant in the following year through a dispute over quality consumption in the spring of the previous year. Second, the weapons elements involved in the Pine cones and the generation of the Pine pollen in the new plant appeared to be P(%), K(%), Ca(%), and Fe(%). However, the nutrients from the previous year's leaves of Ca(%) and Fe(%) were found to have a low influence on the sex determination of first-year pine trees. Because Ca(%) and Fe(%) are not able to move nutrients accumulated in aging organs due to the nature of the components, feeding nutrients in the fall when the growth of the previous year's branches is reduced is expected to affect oral generation. Third, pine trees are extremely positive and Pine pollen is related to the time of the northeast wind. Therefore, it is believed that it would be good to be located in the northern direction, where the sunlight is good, in an outdoor space. In addition, it is important to use vaginal consumer products in spring and carry out a quarrel involving Mg and Fe during fall to reduce the effect of the Pine pollen, which is an outdoor plant. This is an important part of maintaining and managing pine trees in outdoor spaces as well as the sex determination of pine trees. This study suggested that plant planning, which derives the correlation between pine inorganic element content on sexual determination and takes into account the physiological characteristics of pine trees, is an important issue in the creation of outdoor space. Follow-up research on other factors affecting pine tree sex determination is expected.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.45-54
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• 2006

The study was to review methods by which a ship can unfold and tow an oil boom by attaching the opening apparatus to an oil boom through experiments. The shape and dimension of the opening apparatus were designed with the measurement value of the towing tension load of the oil boom and the dimension of winch drum of the oil boom installed in the ship considered. For the field experiment to identify the performance of the opening apparatus, opening apparatuses were prepared to have the dimension of $3.0m^2$ and $6.0m^2$ which is 91% and 75% of the calculation value for type B and C respectively. As a result, T(kg), the value of tension in type B oil boom according to the towing speed(v) change when two ships are towed together were proved to be $T=920v^{1.1}\;and\;T=500v^{0.9}$ in case the distance is 100 m and 50 m. Based on the result, the dimension of the opening apparatus for type B and C oil boom was calculated as $3.3m^2$ and $8.0m^2$ respectively. When unfolding and towing by attaching the opening apparatus and 200 m of towing line at both ends of type B and type C oil boom, the maximum width of the opening apparatus was shown as 114 m and 95 m in average(width of opening/total length of oil boom: 33% and 57%) in the towing speed of 1.5 kt. It was evaluated that the opening apparatus could concentrate the spilled oil in a good performance. However as far as the increase rate of oil boom opening width according to the length of the towing line is debatable, the increase rate is remarkably reduced when it is lengthened from 100 m to 150 m and to 200 m although it showed extreme increase of 31% and 40% when the length of the towing line was changed from 50 m to 100 m. Therefore, it is inferred that the towing line should be maintained more or less 100 m to get good spread efficiency of the opening apparatus. Additionally, if the towing speed is faster than 1.5 kt, the opening width was narrowed because of the reduced spread efficiency and the shape of the oil boom can be unstable because of the partial sinking of the oil boom, run over waves, or flap of skirt. Thus the reasonable towing speed can be within 1.5 kt for the operation of the opening apparatus.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.589-596
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• 2013

Vaccinium bracteatum Thunb. is an evergreen plant that belongs to the Genus Vaccinium distributed in Korea, and its fruit has been used for food by the common people and thus has a high possibility of commercialization. Therefore, the habitat environment and individual characteristics of V. bracteatum in Jeju Island were investigated to obtain the basic data for commercialization and preservation. The results showed that V. bracteatum is mostly distributed on the southern slope of Mt. Halla at an altitude of 100 to 500 m. V. bracteatum that occurred in the quadrat were total 30 individuals, which had an average height of 6.0 m, an average DBH of 7.8 cm, and an average number of trunk of 4.3. As for the community structure of the habitat, the average percentage of vegetation cover for the tree layer was 36%, while that for the subtree layer was 78%, which emphasized the importance of the subtree layer. The total number of species that occurred in the quadrat was 76. For the tree layer, total 10 species occurred, which include 2 species of evergreen coniferous trees, 3 species of evergreen broad-leaved trees, and 5 species of deciduous broad-leaved trees. For the subtree layer, total 24 species occurred, which include 1 species of evergreen coniferous tree, 11 species of evergreen broad-leaved trees, and 10 species of deciduous broad-leaved trees. Among these, Eurya japonica Thunb. was the species with a high relative contribution, which threatened V. bracteatum For the shrub layer, 27 species occurred including Cinnamomum japonicum Siebold, and for the herbaceous layer, 64 species occurred including Ardisia crenata Sims. The similarity between the habitats of V. bracteatum was very low, and it did not prefer a characteristic community. The V. bracteatum community around Shinrei stream was distributed on the surrounding area adjacent to the slope of the stream rather than the slope. There were a lot of basins, but the branches, which did not receive sunlight, had withered. It is thought that V. bracteatum would decline if the forest formation continues.

• Korean Journal of Plant Taxonomy
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• v.41 no.2
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• pp.144-155
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• 2011

The infraspecific taxa of Adonis amurensis Regel et Radde are currently known to include one subspecies (subsp. nanus Y. Lee), two varieties (var. ramosa Makino, and var. dissectipetalis Y. Lee) and two forms (for. argentatus Y. Lee, and for. viridescensicalyx Y. Lee). Among them, the remaining three taxa except for subsp. nanus and var. dissectipetalis are unified with A. amurensis. Therefore, we examined the morphological characteristics and geographical distribution of A. amurensis in effort to elucidate the taxonomic status of subsp. nanus and var. dissectipetalis. After the subsp. nanus samples had been transplanted from their type locality, i.e. highland at more than 1,000 m above sea level, to a lowland habitat, we measured the samples' morphological characteristics. The range of values we recorded of the plant height and floral diameter from the subsp. nanus samples were within the parameters used to characterize A. amurensis. Accordingly, subsp. nanus has been characterized as an ecophene of A. amurensis. It is considered as a synonym of A. amurensis. Among the populations of A. amurensis (sensu Y.Lee, author), those with highly dissected petals at their apices have previously been described as var. dissectipetalis. However, this characteristic has been observed together with obtuse or rounded petal apices not only in one population but also in a single individual. However, populations with these characteristics belong to A. pseudoamurensis due to the simultaneous development of leaves and flowers, branched stems, acute leaf apices, and petals that are shorter than sepals. Therefore, we suggest that A. amurensis var. dissectipetalis be unified with A. pseudoamurensis. Very useful characteristics for distinguishing A. amurensis from its relative species are anthesis, the presence or absence of branches, the development of scales into normal leaves, the relative length of the sepals and petals, and the position of the stipules. A. amurensis is geographically restricted to E. Asia, including E. Siberia, and especially on the Korean Peninsula, it is distributed throughout the northern provinces of Gyeonggi province and in Gangwon province, Gyeongbuk province (Mt. Bohyeon-san) and Jeonbuk province (Mt Jeoksang-san) along Baekdudaegan mountain.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.155-165
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• 1996

This study was carried out to identify the phylogenetic relationship among several isolates of Pleurotus species by comparing ITS II region of ribosomal DNA(rDNA) repeat unit. Two primers from ribosomal DNA sequences were chosen to amplify the specific internal transcribed spacer (ITS) II region of Pleurotus spp. The exact ITS II region with an unique band from six species of Pleurotus genus could be amplified using the two primers taken from at the 3'-end of 5.8S rDNA and 5'-end of 28S rDNA. Six representative species of the Pleurotus genus were easily characterized according to the length differences of ITS II region. Furthermore, within P. ostreatus species, different sizes of ITS II region could be observed in the isolates of ASI 2025 and ASI 2095 although they were classified as P. ostreatus by the conventional observation. The nucleotide sequence analyses of PCR-amplified ITS II region indicated that the isolates ASI 2025 and ASI 2095 were different from other Pleurotus spp. When the nucleotide sequences of six Pleurotus species were compared, three typical ITS II regions were highly variable especially at both ends of this region. The phylogenetic tree obtained by the Neighbor program of Felsenstein PHYLIP package with all the nucleotide sequence of Pleurotus spp. indicated that P. ostreatus, P. florida, P. sajor-caju and P. eryngii were closely related to one phylogenetic branch and P. cystidious was related to other branch with P. cornucopiae. The isolates ASI 2025 and 2038, however, were not closely related to any other Pleurotus spp. and formed their own individual branches.

• Journal of Wetlands Research
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• v.16 no.2
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• pp.245-250
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• 2014

This study developed allometry equation and estimated the aboveground-biomass of Quercus glauca, a warm-temperature, evergreen broad-leaved tree, growing in Kotzawal wetland located on Jeju Island. The allometric equations between DBH(diameter at breast height) and dry weights of stems (Ws), branches (Wb), leaves (Wl) and aboveground biomass (Wab) of Q. glauca were as follows: logWs=2.4042logDBH-1.3045, logWb=2.6436logDBH-1.6232, logWl =1.5428logDBH-1.3692 and logWab=2.3324logDBH-0.9181. The allometric equations between $D^2H$ and Ws, Wb, Wl, and Wab of Q.glauca were as follows : logWs=$0.853logD^2H-1.4252$, logWb=$0.8453logD^2H-1.5834$, logWl=$0.5328logD^2H-1.4073$ and logWab=$0.8453logD^2H-1.0327$. The $R^2$ between DBH and Ws, Wb, Wl and Wab were 0.9873, 0.9711, 0.7979 and 0.993, respectively. The $R^2$ between $D^2H$ and Ws,Wb,Wl and Wab were 0.9841, 0.9174, 0.7537 and 0.9876, respectively. There was no significant difference between observed and calculated values of the allomatric equations from DBH and $D^2H$(p>0.05, Kolmogorov-Smirnov test). Thus, to estimate the aboveground biomass of Q. glauca, use of DBH and $D^2H$ as an independent variables in the allometric equation is recommended.

• Korean Journal of Medicinal Crop Science
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• v.3 no.1
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• pp.1-4
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• 1995

To determine the optimum sowing time and nursery period in Perilla frutescens in the southern areas of Korea, perilla frutescens cv. red Perilla local cultivar was grown under three different sowing dates and nursery periods. The blooming period of the area which was sown on the seedbed in Apr.10 and carried out the growing seedling in 30days is Aug. 12 and it is two days earlier than that of the area, Aug.14, sown on the seedbed in Apr. 20 and carried out the growing seedling in 30days of the same month and it is also six days earlier than that of the area, Aug.18, sown on the seedbed in April 30 and conducted the growing seedling in the same date. The stem lengths are 135cm,131cm and 125cm respectively and the number of branches are 26.4, 25.3 and 23.6 respectively. The fresh weight of stem and leaf at the area sown on the seedbed in Apr.10 and conducted the growing seedling in 30days with the width of leaf over 5cm in the middle of Aug. and at the beginning of Sep. is 2,476kg/10a and it shows more increase of 172kg than that of fresh weight of stem and leaf with 2,304kg/10a which was sown on the seedbed in Apr.20 and earned out the growing seedling in 30days, and it also shows more increase of 411kg than that of fresh weight of stem and leaf with 2,065kg/10a at the area sown on the seedbed in April 30 and con­ducted the growing seedling in the same date, The fresh weight of seeds are 609.5kg/10a,509.3kg/10a and 463.2kg/10a respectively and $100.2{\sim}146.3kg$ is more increased. Therefore, the seedling period of the proper seedbed for high yield bumper crop of perilla frutescens for exporting to Japan is April 10 and the number of days for seedling is 30 days.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.323-330
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• 2010

This study was undertaken to compare early growth characteristics, such as height, diameter at root collar (DRC), and the dry weights of stem, branches, needles and roots between naturally regenerated and planted stands of Pinus densiflora for. erecta in Dae-gi and Bo-gwang site, Gangwon province, Republic of Korea. Average DRC growth was similar between the naturally regenerated and the planted stands in Dae-gi area, however, difference was statistically significant (P<0.01) between the naturally regenerated and the planted stands in Bo-gwang area, 4.66 cm and 2.61 cm, respectively. Average height of the naturally regenerated stands was significantly greater (P<0.01) than that of planted stands in both Dae-gi and Bo-gwang areas. The composition ratio of the dry weights for each part of measured trees was the highest in the stem in the naturally regenerated stands, but in the planted stands, the needle was the highest in both sites. The root/shoot ratio in the Dae-gi and Bo-gwang areas in the planted stands were much greater than those in the naturally regenerated stands, 0.25-0.30 and 0.17-0.18, respectively. The ratio of needle to stem biomass (N/S), branch to stem biomass (B/S), and needle to branch biomass (N/B) was significantly greater in the planted stands than those in the naturally regenerated stands in both sites. The results of this study represent that the regeneration methods, natural and artificial regenerations, can have an influence on the early growth of P densiflora for. erecta. This results not only provide the need for a correct planting method, but also will be useful in studies on the environmental adaptability of trees.