• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.4
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• pp.330-336
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• 2004

To meet the increasing demand from various fishing fields for training of fishing equipment operators, a fishing winch simulator was designed to train maritime students in the correct and safe operation of hydraulic winches under various load conditions related to fishing operations. The aim of this study is to describe the basic dynamic characteristics of the newly developed hydraulic fishing winch simulator and particularly to analyze the mechanical responses produced on the winch operation controls. The winch simulator consists of two winch units, a computer control and data acquisition system, a control consol and other associated mechanisms. When one winch is in hauling mode, the other one will always be in loading mode. The revolution speed of the hauling winch was controlled by a proportional directional control valve, and the braking torque of the loading winch was controlled by a proportional pressure control valve. The simulation experiments indicated that the dynamic characteristics of the hauling winch followed the braking response characteristics of the loading winch. The tests also showed that the warp speed and tension linearly depend on the pressure differential across the motor of the loading winch controlled by operating the proportional pressure control valve during the hauling operation. The experience gained from various training courses showed that the fishing winch simulator was very realistic and it was valuable for training novice winch operators. The results of the winch simulation exercise were recorded and used to evaluate the training on the operation and handling of the winch system. From these test results, we concluded that the tension acting on the warp during hauling operations can successfully be simulated by controlling the pressure differential across the motor with step changes of the control input signal to the proportional pressure control valve of the loading winch.

• Journal of the Korean Institute of Gas
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• v.12 no.2
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• pp.92-98
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• 2008

A combination of the instrumented indentation and 3D morphology measurement has been tried in order to perform a real-time property measurement of degraded materials in gas pipelines; three-dimensional indent morphologies were recorded using a reflective laser scanner after a series of insturmented indentations on three metallic specimens. Dimensions of the permanent deformation zone and contact boundary were analyzed from the cross-sectional profile over an remnant indent and used for estimating yield strength and hardness, respectively. Estimated yield strength was comparable with that from uniaxial tensile test and actual hardness implying material pile-up effects was lower than the calculated value from indentation curve by $20{\sim}30%$. It means that this 3D image analysis can explain the material pile-up effects on the contact properties. Additionally, a combined system of indentation and laser sensor was newly designed by modifying a shape of the indentation loading fixture.

• Journal of Species Research
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• v.2 no.1
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• pp.15-54
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• 2013

Surveys on Jeju-do (Quelpart Isl.) unearthed about 40 earthworm species or sub-species. Several considered new to science are described. Only a dozen were previously known and these are taxonomically reviewed. The two most commonly recorded in surveys by S. Kobayashi in the 1930s were Drawida anchingiana Chen, 1933 and Metaphire quelparta (Kobayashi, 1937), neither recently relocated. Morphologically similar taxa, supported with DNA barcodes, for Moniligastridae, are Drawida anchingiana seogwipo, D. anchingiana halla and D. iucn spp. or sub-spp. nov. For Megascolecidae, new taxa and synonyms are: Amynthas arx and A. aucklandis spp. nov. that have seminal grooves rather than the eversible male pores of Metaphire plus Amynthas simplex is another new species. Amynthas sangumburi Hong & Kim, 2002 is recognized as a probable new synonym within the A. corticis (Kinberg, 1867) species-group while Amynthas corticis saeseum sub-sp nov. is described. Amynthas gracilis (Kinberg, 1867) is a new record from Jeju and Korea (with A. bouchei, A. omodeoi and A. edwardsi all by Zhao & Qiu, 2009 possible synonyms of this species group from China) with a Jejuan sub-species, A. gracilis insularum, sub-sp. nov. Presence on Jeju of Amynthas carnosus (Goto & Hatai, 1899) is confirmed (its further new synonyms are Chinese A. fuscus Qiu & Sun, 2012 and A. taiwumontis Shen et al., 2013), as is A. micronarius (Goto & Hatai, 1898) (with new synonym A. montanus Qiu & Sun, 2012 also an invalid secondary homonym). Amynthas phaselus maculosus (Hatai, 1930) is in new combination with A. kamitai (Kobayashi, 1934) and A. minjae Hong, 2001 syns. nov. Two newly described Metaphire quelparta sub-spp are M. q. seogwipo and M. q. valhalla these being supported with DNA barcodes despite the nominal taxon not yet being confirmed.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.241-247
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• 2019

In 2017, we collected a wood-decay fungus growing on a dead and decaying herbaceous plant (Reynoutria sachalinensis (F. Schmidt) Nakai) in Dokdo, the far-eastern island of South Korea. Morphologically, this species is characterized by resupinate, coriaceous to corky basidiocarps, poroid hymenophores, pseudodimitic hyphal system, and ellipsoid basidiospores. Based on morphological observation and internal transcribed spacer of ribosomal DNA, the fungus was identified as Xylodon flaviporus (Berk. & M.A. Curtis ex Cooke) Riebesehl & Langer. It is only the second macrofungal species reported from Dokdo, and R. sachalinensis is the first herbaceous plant to be identified as a host for X. flaviporus.

• Korean Journal of Plant Taxonomy
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• v.34 no.4
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• pp.287-295
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• 2004

Daucus species vegetated in the island Dae-heug-san-do off the Korean Peninsula has been recorded as Daucus littoralis Sibth. et Sm. var. koreana Nakai, endemic to Korea in several flora. However, the name was revealed as a naked name, nomen nudum, because the valid publication and type specimens were found anywhere. Comparative observation on morphological characters between the Korean taxon of Daucus and D. littoralis reveals that the Korean vegetated in the island Dae-heug-san-do is not the D. littoralis, but the D. carota L. subsp. carota. The Korean name of the latter is designated newly as San-dang-geun. The new korean name, Seon-dang-geun, of the unrecorded taxon, D. carota subsp. maritimus (Lam.) Batt., is also given.

• Korean Journal of Plant Taxonomy
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• v.51 no.3
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• pp.294-304
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• 2021

Given that the Korean genus Elymus L. (Poaceae) is often confused with Agropyron Gaertn., the categories and characteristics of Elymus s.l. have been reviewed morphologically. Two unrecorded taxa of Elymus, E. humidus (Ohwi & Sakam.) T. Osada and E. shandongensis B. Salomon, not previously recorded in Korean flora to date, we report here as an unrecorded species based on samples collected from Chungcheongbuk-do, Gyeongsangnam-do, Jeollanam-do, and Jeollabuk-do. E. humidus is distinguished from other taxa in terms of its habitat around riversides, erect inflorescences, spikelets appressed to rachides of inflorescence, and new individuals asexually propagated at the lower nodes of aerial stems. E. shandongensis is similar to E. tsukushiensis var. transiens (Hack.) H. Osada but is distinguished by the flowering time, slightly curved inflorescences, number of veins of the glumes, and spikelets appressed to the rachides. Descriptions of the two unrecorded Korean taxa, photographs, and keys to neighboring taxa are presented.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.240-258
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• 2018

Background: Several investigations carried out from large brackish lagoons in South Korea. However, no studies have yet examined phytoplankton in lagoons that changed to freshwater, such as Cheonjin Lake. The present study examined the algae from Cheonjin Lake. Methods: Samples were collected at monthly inetrvals from May 2017 to April 2018, from the surface layer using a plankton net (mesh size $20{\mu}m$), and sequeezing submerged macrophytes. Microscopic examinations were conducted at a magnification of 200 to 1000x using a Zeiss microscope (Axio Imager. A2), and photographs were taken with an AxioCam HRC camera. Silica-scaled samples of Chrysophyta for SEM were placed on coverglass, air dried, coated with gold, and then examined with a Hitachi SV8220 SEM. Results: A total of 376 taxa from six major algal groups (Chlorophyta, Chrysophyta, Euglenophyta, Cyanophyta, Dinophyta, and Cryptophyta) were identified. Among these algae, 28 taxa of desmids, 9 taxa of Euglenophyceae, 4 taxa of Chlorophyceae, 2 taxa of Chrysophyceae, and 1 taxon of Xanthophyceae are reported for the first time in Korea. A new species, Cosmarium hexagonum sp. nov was described. The phytoplankton communities were characterized by an abundance of Desmids (within Charophyceae) accounted for 148 taxa from 22 genera. Species richness were particularly high in the Autumn. Conclusion: In this study, a total 376 taxa of 148 desmids (Charophyceae), Chlorophyceae (103 taxa), Chrysophyceae (53 taxa), Euglenophyta (49 taxa), Dinophyta (8 taxa), and Cryptophyta (2 taxa) were identified from Cheonjin Lake. Twenty-eight taxa of desmids including a new species (Cosmarium hexagonum sp. nov.), 9 taxa of Euglenophyceae, 4 taxa of Chlorophyceae, 2 taxa of Chrysophyceae, and 1 taxon of Xanthophyceae were newly recorded in Korea.

• Journal of Contemporary Eastern Asia
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• v.18 no.1
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• pp.7-29
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• 2019

This study describes an approach for comparative bibliometric analysis of scientific publications related to (i) individual or several departments comprising a university, and (ii) broader integrated subject areas using multiple disciplinary schemes. It uses a custom dataset of scientific publications (ca. 15,000 articles and reviews, published during 2009-2013, and recorded in the Web of Science Core Collections) with author affiliations to the research departments, dedicated to science, technology, engineering, mathematics, and medicine (STEMM), of a comprehensive university. The dataset was subjected, at first, to the department level and discipline level analyses using the newly available KAKEN-L3 classification (based on MEXT/JSPS Grants-in-Aid system), hierarchical clustering, correspondence analysis to decipher the major departmental and disciplinary clusters, and visualization of the department-discipline relationships using two-dimensional stacked bar diagrams. The next step involved the creation of subsets covering integrated subject areas and a comparative analysis of departmental contributions to a specific area (medical, health and life science) using several disciplinary schemes: Essential Science Indicators (ESI) 22 research fields, SCOPUS 27 subject areas, OECD Frascati 38 subordinate research fields, and KAKEN-L3 66 subject categories. To illustrate the effective use of the science mapping techniques, the same subset for medical, health and life science area was subjected to network analyses for co-occurrences of keywords, bibliographic coupling of the publication sources, and co-citation of sources in the reference lists. The science mapping approach demonstrates the ways to extract information on the prolific research themes, the most frequently used journals for publishing research findings, and the knowledge base underlying the research activities covered by the publications concerned.

• Journal of Dental Anesthesia and Pain Medicine
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• v.19 no.4
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• pp.227-233
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• 2019

Background: Dental anxiety in children is a major barrier in patient management. If dental anxiety in pediatric patients is assessed during the first visit, it will not only aid in management but also help to identify patients who are in need of special care to deal with their fear. Nowadays, children and adults are highly interested in multimedia and are closely associated with them. Children usually prefer motion pictures on electronic devices than still cartoons on paper. Therefore, this study was conducted to evaluate a newly designed scale, the animated emoji scale (AES), which uses motion emoticons/animojis to assess dental anxiety in children during their first dental visit, and compare it with the Venham picture test (VPT) and facial image scale (FIS). Methods: The study included 102 healthy children aged 4-14 years, whose dental anxiety was measured using AES, VPT, and FIS during their first dental visit, and their scale preference was recorded. Results: The mean anxiety scores measured using AES, FIS, and VPT, represented as $mean{\pm}SD$, were $1.78{\pm}1.19$, $1.93{\pm}1.23$, and $1.51{\pm}1.84$, respectively. There was significant difference in the mean anxiety scores between the three scales (Friedman test, P < 0.001). The Pearson's correlation test showed a very strong correlation (0.73) between AES and VPT, and a strong correlation between AES and FIS (0.88), and FIS and VPT (0.69), indicating good validity of AES. Maximum number of children (74.5%) preferred AES. Conclusion: The findings of this study suggest that the AES is a novel and child-friendly tool for assessing dental anxiety in children.

• Journal of Practical Engineering Education
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• v.13 no.2
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• pp.243-249
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• 2021

It has been determined the 6 core competencies of our university students. Among them, it was judged that the student's convergence thinking ability and self-development ability were insufficient. To enforce the two insufficient abilities, an engineering-related major collage course was newly established in the form of an intensive coursework. The course was conducted as a shared curriculum between division/departments. For each of the first and second semesters in the 2020, 54 students from two completion groups (Department of Electrical and Electronic Control Engineering; 26, Optical Engineering; 28) were the subjects of the survey, the survey results of 20 common questions were comprehensively analyzed. As the result, more than 75% of the respondents were positive about free online learning at any time and place. And if additional interactive activities and team teaching method are reinforced during recorded audio and video contents learning material, It is confirmed that the attempted intensive course can maximize the learning effect.