• Korean Journal of Plant Taxonomy
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• v.52 no.2
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• pp.97-101
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• 2022

Saussurea namhaedoana, a new endemic species narrowly restricted to Namhaedo Island of Korea, is reported in this study. It can be distinguished from other congeneric species of Saussurea in Korea by having persistent radical leaves until flowering, hastate or sagittate leaves with mucronate toothed to undulate-lobulate margins, grayish cobwebby hairs on abaxial leaf surfaces when young, and tubular involucre with grayish cobwebby hairs. Morphologically, S. namhaedoana is closely related to other species in Korea, such as S. gracilis Maxim., S. insularis Kitam., S. seoulensis Nakai and S. albifolia M. J. Nam and H. T. Im, sharing grayish or white hairs on the abaxial leaf surfaces. It, however, can be distinguished from its close relatives by having a distinct leaf shape, i.e., sagittate or hastate leaves. The phylogenetic relationship relative to congeners in East Asia is yet to be determined.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.100-108
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• 2022

We found Urtica dioica L., an unrecorded alien plant, in the Han River basin of Korea. U. dioica is considered to be native to Europe, much of temperate Asia and western North Africa. This plant has been introduced to many other parts of the world. In Particularly, it reported as an invasive species from East Asia (Japan), Oceania and South America. This species is distinguished from related Korean taxa of the genus by its unisexual flower and dioecious plant species. In the Neighbor-Joining tree, U. dioica samples from the Han River Park (Sangam-dong, Mapo-gu, Seoul) and Yangjaecheon Stream (Daechi-dong, Gangnam-gu, Seoul) clustered into a clade consisting of a U. dioica s.s. Here, we provide a precise description, illustrations, a key to the related taxa, and photographs of its habitat.

• Korean Journal of Plant Resources
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• v.35 no.2
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• pp.242-247
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• 2022

Richardia brasiliensis Gomes was found in agricultural land in Susan-ri, Seogwipo-si, Jeju-do. Richardia L. is closely related to Diodia L. in Korea, those are confirmed to features of calyx, collora and fruit. This species is similar to R. scabra L., but it differs morphologically from the letter in surface structure of mericarp. The mericarp of R. brasiliensis has line like kneel at the adaxial, whereas R. scabra has groove at the adaxial. R. brasiliensis is recorded for the first time in this study and a morphological description, distribution map, and photographs are presented.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.4
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• pp.81-92
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• 2022

In this study, interview scripts written in the dropout application was analyzed using BERTopic,, and parental influence, academic adaptation, university dissatisfaction was derived as major topics. An empirical study was conducted through a survey of 199 current students with researchmodel composed of those factors affecting dropout intention. The result shows that parental influence had a negative effect on academic adaptation and university satisfaction. Academic adaptation and university satisfaction had a negative effect on the dropout intention. parental influence did not directly affect the dropout intention, but had an indirect positive effect through academic adaptation and university/major satisfaction. The result shows that university satisfaction and academic adaptation is important factor to lower the dropout intention of students who chose current university by parental influence.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.607-613
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• 2022

Vulpia octoflora (Walter) Rydb., a newly identified invasive alien species, was found in Gangcheon-ri, Yeoju-si, Gyeonggi-do, South Korea. It is native to North America and has been reported to be an invasive alien plant in Japan, Australia, and Ukraine. Vulpia octoflora is a weed that grows mainly in dry sandy or rocky soil and is frequently found along the roadside in open areas or in artificially disturbed sites. This species is similar to the recently confirmed alert alien species, V. bromoides (L.) Gray, but is readily distinguishable due to more florets per spikelet and a short awn of the lemma. A detailed species description, the geographical distribution, illustrations, photographs, and an identification key for all species of Vulpia that occur in Korea are provided.

• Journal of Digital Convergence
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• v.20 no.2
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• pp.399-405
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• 2022

This study suggests focused in user-centered design which are new separate discharge system that must recycle in paper materials. I searched cases in Korea's current law and regulation in recycling disposal guidelines and already succeed cases in each city that are Asia, Europe, and North America. Suggesting focused in user-centered design of ID(Identification) separate discharge system due to user's good participations, feedbacks of participation's results, and well-organized in awarding. This system consists of visual individual's ID(Identification) that are stickered in only used bag. User must recycle in separate discharge system only used bags, and results must visualized in each user and rewards to user. This separate discharge system is meaning to stimulate user's good participations.

• Korean Journal of Ichthyology
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• v.34 no.2
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• pp.138-143
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• 2022

Based on three specimens (50.6~67.7 mm SL) collected from the southern coastal waters of Jejudo Island, Oxycheilinus bimaculatus was described as the first record from Korea. They were characterized by having two small dark spots behind eye on head and body posterodorsally, a rhomboid caudal fin with elongated central rays and produced uppermost ray as a filament in terminal male, six predorsal scales, and two scale rows on cheek. We proposed a new Korean name, "Du-jeom-gin-ju-dung-i-nol-rae-gi", for the species referring to having two dark spots on head and body.

• Journal of Marine Life Science
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• v.7 no.1
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• pp.55-59
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• 2022

This study was conducted to provide basic information on the sexual mature and reproductive biology of Trichiurus lepturus. During the oogenesis, size of oocyte and nucleus showed the increase tendency but size ratio of nucleolus to nucleus was decreased. In the result of H-E stain, the stainability of the cytoplasm was changed from basophilic to eosinophilic. The egg diameter of initial vitellogenic oocyte was about 63.2 (±12.7) ㎛. In the cytoplasmic cortex, eosinophilic yolk nucleus was observed. The size of mature oocyte was 216.6 (±24.7) ㎛ and GVBD (germinal vesicle breakdown) was observed. The size of ripe oocyte was 317.9 (±80.9) ㎛ and the thickness of zona radiata was 4.2 (±1.7) ㎛. The oocyte developmental type is considered to belong to the group synchronous type. The accumulation of yolk in the oocyte, like most teleost, is thought to be of two types: exogenous and endogenous accumulation.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.381-385
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• 2022

It is very important to secure the adhesion durability between the base film and the conductive paste for the development of a sensor for detecting hazardous chemicals. In this study, an ester binder was used to improve the adhesive properties which can be a problem when applying the sensor to the cross cut 0B or 1B grade. This problem was found while evaluating the adhesive properties by coating the polyaniline/graphene nano plate (GNP) paste on the polyethylene terephthalate (PET) film. When 10 wt% or more of the ester-based binder was added, the cross cut grade to which the sensor can be applied was 3B or higher. It was confirmed that the excessive addition of the binder may affect the electrical properties of the conductive paste and actually decrease the reactivity to sulfuric acid. To improve the electrical property, a carbon black (CB) content was varied resulting in the optimum electrical property observed at 2 wt% of CB.

• Journal of the Korean earth science society
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• v.44 no.2
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• pp.161-168
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• 2023

While numerous previous studies investigated the provenance and tectonic history of the Gyeongsang Supergroup, less are known about other Cretaceous strata in South Korea. This study presents preliminary results from petrographic analysis of the Cretaceous Icheonri Formation distributed in Gijang-gun, Busan. Based on the immature texture and composition of the Icheonri sediments, we interpret that they were derived from weakly denudated Cretaceous arc volcanoes developed along the eastern margin of the Asian continent, with limited weathering and transport. Additionally, the presence of chrome spinel grains in the sediments suggests the existence of ultramafic bodies exposed in their provenance. Further studies will advance our understanding of the tectonic developments in the southeastern Gyeongsang Basin, and facilitate a comprehensive correlation between the Icheonri Formation and the Gyeongsang Supergroup.