• The korean journal of orthodontics
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• v.39 no.3
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• pp.159-167
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• 2009

Objective: This study investigated the onset, peak height velocity (PHV) and end of adolescent growth spurt as well as menarcheal timing deduced from surveying accumulative height growth over many years. Methods: Ninety six students of Samgoe high school between 1st and 3rd grade that were in good health participated in the research. A survey questionnaire was distributed to examine the students' health status and menarche timing. Results: Adolescent growth spurt typically began at the age of 9.9 and reached a PHV at the age of 11.6. The growth spurt ended at the age of 14.1 on average. The average age of menarche was 12.6 years, which was about one year after the PHV of adolescent growth spurt. In most cases, menarche came after PHV. But in 24% of the students, menarche and PHV was nearly coincident or menarche preceded PHV. The growth curves were classified into four types. A typical adolescent growth spurt showed one PHV on graph that drastically drops after the PHV. However, there were cases with two PHVs. Conclusions: The results indicate that individual growth patterns show large individual differences, however the categorization into the various growth curves may aid in predicting individual growth patterns.

• Journal of Digital Convergence
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• v.8 no.2
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• pp.147-160
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• 2010

Internet shopping mall business has taken its place as a major form of e-commerce and is evolving constantly. At the same time, disputes of various kinds are also arising in proportion to the evolution. A typical example is when a consumer purchased a product from an internet shopping mall and the seller wants to cancel or withdraw the sales contract saying that he miswrote the price or other important information when posting the product on the internet. It's about the error on the seller's part. Civil Law Chapter 109, legal principles on errors, appears to assume the case of natural declaration of intention. It was observed that legal principles on errors defined by the Civil Law are also applied in internet shopping malls, where declaration of intention is made electronically. In transactions involving internet shopping malls, where the seller's indication and advertisement constitutes an inducement to offer, the seller may cancel a contract concluded by the consumer's offer and the seller's acceptance if the seller finds errors on his part, and adequacy of the cancellation should be judged depending on specific cases. That is, the judgment of the important ground that comprises prerequisites for cancellation and presence of negligence may depend on how much difference there is between the normal price and the posted price on a specific case. Also, considering the cases where negligence was not perceived on the seller's miswriting of the price, the seller may cancel the transaction in a similar situation.

• Korean Journal of Environment and Ecology
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• v.12 no.1
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• pp.91-101
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• 1998

Two large communities of Vicex rotundifolia were discovered for the first time at the beach of Pyonsanbando National Park. The growth environment and morphological characters of the communities were examined and analyzed to provide some basal data which would be helpful to establish measures for protection and to utilize the communities rationally. The results are as follows; The habitats of Vitex rotundifolia are located at Chakeundang beach of Kyokpo-ri and Kosapo beach of Woonsan-ni, Pyonsan-myon in Pyonsanbando National Park. The total area of this two communities was measured to be 2,755m$^{2}$ and 523m$^{2}$ of it was damaged. Two varieties, 49 species, 43 genera and 28 families as trees and shrubs were collected from inside of and the vicinal areas of the communities. Koelreuteria paniculata and Rosa rugosa were discovered and collected in these areas for the first time to be documented with the communities of Vitex rotundifolia. The largest individual of Vitex rotundifolia within the polulations reaches or 3.5cm in diameter at root collar and 6m in length of the runner on aboveground. The individuals of Vitex rotundifolia within the communities show good growth condition which the mean leaf length was measured to be 4.5cm, the mean leaf width 3.3cm, the mean leaf area 11.8cm$^{2}$ and the mean flower length 10.0cm. Vitex rotundifolia has been mostly recorded to be an evergreen shrub. But the present study discovered that it is rather deciduous.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.195-200
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• 2006

This study was carried out to clarify the biologies and morphological characteristics of Rhynchaenus sanguinipes. Also some chemicals were tested to screen the effective insecticide for the control of the species. Up to date, Zelkova serrata has been hewn as host plant of Rhynchaenus sanguinipes, which shows serious damage in this country. In the present study, Ulmus pumila was first found as host plant in this study. Body lengths of larvae, pupa and adult were 4.53$\pm$0.30 mm, 3.30$\pm$0.42 mm and 2.96$\pm$0.12 mm, respectively. The overwintered adult of the species emerged on early April to late April, and adult of nekt generation emerged on early May to late May, Pupal periods were 10, 7.2, 5.1 and 4 days on 16, 20, 24 and 28$^{\circ}C$, respectively. The lower developmental threshold temperature was 5.8$^{\circ}C$. Four braconid parasitoids were found as natural enemies, which emerged mainly on late April to early June. Insecticidal activities with treatments of fenitrothion 50% EC, indoxacarb 30% WG, ethofenprox 20% EC and thiacloprid 10% SC was investigated against adult of R. sanguinpes, and they showed >90% mortality.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.387-392
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• 2015

A method for measuring and analyzing the $NO_x$ in ships is described in $NO_x$ Technical Code 2008. The analysis device, as required by the Code, has been to use a Chemi-luminescence detection method or Heated Chemi-luminescence detection. on the other hand, selective catalytic reduction using $NH_3$ as a reducing agent has an interference effect on the analyzer, and causes measurement error. In this study, the Chemi-luminescence detection method was examined according to how it affects the concentration of $O_2$, CO, $SO_2$, $NH_3$. Fourier transform infrared spectrometry analysis equipment and measurement methods were compared. In order to confirm the effect of the physical interference of the measuring device, it was confirmed by decomposing a measuring device. Consequently, white precipitate and moisture were generated inside the chemiluminescence detection system and I found that affecting interference. The influence of interference highlights the need to consider the minimized $NO_x$ measurement method.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.121-149
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• 2008

Taxonomic treatment and the identification key for 6 species and 4 varieties from the genus Asarum (Aristolochiaceae) in Korea were presented on the basis of the morphological analyses. Recently the taxonomy of the genus Asarum in Korea is controversial in the definition of species and the establishment of variation range. Our morphological studies supported that the species A. patens, A. misandrum and A. versicolor should be recognized as independent species by the unique morphological characters such as calyx lobes, stylar protuberance and leaf variegation. Second, A. sieboldii var. cornutum, A. koreanum, A. maculatum and A. sonunsanense, regarded as species or variety by different scholars, showed a close relationship with A. sieboldii by the similar calyx characters. Thus, new combinations, such as A. sieboldii for. cornutum, A. sieboldii for. koreanum, A. sieboldii for. maculatum and A. sieboldii for. sonunsanense, are proposed. And A. heterotropoides var. seoulense and A. heterotropoides var. mandshuricum also had a close relationship, thus, new combinations, A. mandshuricum for. seoulense, A. mandshuricum for. mandshuricum, are proposed. Furthermore, it is appropriate that A. heterotropoides var. heterotropoides, only distributed in Japan, is revised into A. heterotropoides as independent species by the unique character from the 2 varieties above. Consequently, the genus Asarum in Korea is classified into 3 species and 7 forma.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.79-91
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• 2008

Asplenium yoshinagae (Aspleniaceae), previously known only from Japan, southwest China to Himalaya, was found in Gageo-do, Heuksan-myeon, Sinan-gun, Jeollanam-do. This species is similar to A. trichomonas, A. tripteropus, A. boreale, A. normale and A. oligophlebium by having gemmae and auricle of pinna, and distinguished from the latters by distinct stipe length, stalk of pinna, acute apex of pinna, length of indusium and shape of sorus. The Local name, Ga-geo-kko-ri-go-sa-ri, was newly given considering the locality. To reveal the interspecific relationships within the genus Asplenium in Korea, cladistic analysis was performed for 22 taxa of Asplenium as ingroup and 2 taxa of Diplazium as outgroup from Korea based on 20 morphological characters. As the results, the genus Asplenium seperated strongly from outgroup, and divided into 4 clades. Asplenium yoshinagae belong to the third clade. A. hondoense N. Murtakami & S. I. Hatanaka, which contained in the second clade, had treated as Hymenasplenium, but this results supported that this taxon may be contained in Asplenium, and also, Asplenium ruprechtii, not in Comptosorus. The morphological characters and illustrations of the species are provided together with photographs of habitat.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.389-403
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• 2008

Seed morphological studies of 12 species of sect. Zygophyllidium and related Poinsettia using light and scanning electron microscopy were conducted to test the hypotheses of the sectional boundaries and species relationships. Characteristics of seeds, and the keys of identification of 12 species were presented. Seeds of 12 species were divided into 6 types based on the UPGMA tree from numerical analyses using nine seed characters. Type I, including E. uniglandulosa, is characterized by the foveolate seed with granulate testa cells. Type II, including species E. exstipulata, E. lagunensis, E. bilobata, E. hexagonoides and E. chersonesa, was recognized by the presence of inter-cellular granules among testa cells. Type III, including E. cyathophora, has a seed with acute apex, and concentric circles on the surface of testa cells. Type IV, including species of E. dentata and E. pentadactyla, has a seed with caruncle and lacking inter-cellular granules among testa cells. Type V, including E. hexagona, was characterized by the ovate seeds and lacking inter-cellular granules. Type VI, including E. eriantha and E. lacera, was recognized by the seeds with rectangular shape with caruncle. Based on the seed morphology, sect. Zygophyllidium should be defined only species with E. exstipulata, E. lagunensis, E. bilobata, E. hexagonoides and E. chersonesa. E. hexagona, traditionally included in this section, was closely related to E. dentata from Poinsettia.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.405-431
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• 2008

Cuticle micromorphology of 22 species of Quercus and outgroup were examined by the SEM. Twenty-two species selected each two or three species in all section of the genus Quercus. The genus Trigonobalanus and Alnus are selected as outgroups. Ten characters of the inner surface and eight characters of the outer surface of the cuticle have been described. Some characters, such as the present of papillae, arrangement of subsidiary cell, shape of anticlinal cell wall are considered important character for infrageneric classification. A parsimony analysis of 18 characters resulted in 72 most parsimonious trees with its lengths of 66 steps. The topology obtained from the analysis showed two major lineages. Subgenus Cyclobalanopsis formed one clade by 75% and subgenus Quercus formed another clade by 57% bootstrap value. Based on the cuticle morphology, the two subgenus delimitation of Camus was supported. However, sect. Erythrobalanus and sect. Cerris formed one group, and sect. Lepidobalanus formed polytomy.

• Korean Journal of Plant Taxonomy
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• v.45 no.2
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• pp.145-157
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• 2015

The nucleotide sequences of nuclear ribosomal ITS regions and chloroplast rbcL, matK and psbA-trnH regions of 30 individuals of Dendrobium moniliforme from several localities in four countries and 28 related species of Dendrobium were compared to investigate the genetic differences among Korean, Japanese, Taiwanese and Chinese D. moniliforme, and to verify the homogeneity of D. moniliforme, which is used as a traditional medicine in East Asia. A phylogenetic analysis showed that Korean D. moniliforme and Japanese D. moniliforme form a monophyletic group, with no significant differences between their nucleotide sequences. This confirms that they are the same species. However, the Chinese and Taiwanese D. moniliforme were polyphyletic. Various species related to D. moniliforme were located between the Korean-Japanese D. moniliforme and the Chinese-Taiwanese D. moniliforme, and other related species were found between individuals of Chinese-Taiwanese D. moniliforme. D. moniliforme is described in Japan, providing evidence that the Korean-Japanese D. moniliforme is the original species. In addition, our data suggest that the Chinese-Taiwanese D. moniliforme complex is a mixture of a range of other species. Further studies are required to understand the taxonomic identity of this species. In the Korean-Japanese D. moniliforme, there were almost no genetic differences among the localities, whereas the genetic heterogeneity was high among individuals of the Chinese-Taiwanese D. moniliforme.