• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.340-344
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• 2014

A single specimen of Pseudocaranx dentex (115.8 mm in standard length), belonging to the family Carangidae, was firstly collected by a set net in the coastal waters of Jeju Island on July 14, 2014. This species was characterized by a yellow stripe presented along both sides, a single series of canine teeth arranged on jaws, a black spot on upper margin of opercle, and snout length longer than eye diameter. We newly add this species to the Korean fish fauna and propose its Korean name "Heuk-jeom-jul-jeon-gaeng-i-sok" and "Heuk-jeom-jul-jeon-gaeng-i" for the genus and species, respectively.

• Earthquakes and Structures
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• v.1 no.4
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• pp.327-344
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• 2010

This paper summarizes results of a comprehensive analytical study aimed at evaluating the influence of strong ground motion duration on residual displacement demands of single-degree-of-freedom (SDOF) and multi-degree-of-freedom (MDOF) systems. For that purpose, two sets of 20 earthquake ground motions representative of short-duration and long-duration records were considered in this investigation. While the influence of strong ground motion duration was evaluated through constant-strength residual displacement ratios, $C_r$, computed from the nonlinear response of elastoplastic SDOF systems, its effect on the amplitude and height-wise distribution of residual drift demands in MDOF systems was studied from the response of three one-bay two-dimensional generic frame models. In this investigation, an inelastic ground motion intensity measure was employed to scale each record, which allowed reducing the record-to-record variability in the estimation of residual drift demands. From the results obtained in this study, it was found that long strong-motion duration records might trigger larger median $C_r$ ratios for SDOF systems having short-to-medium period of vibration than short strong-motion duration records. However, taking into account the large record-to-record variability of $C_r$, it was found that strong motion duration might not be statistically significant for most of the combinations of period of vibration and levels of lateral strength considered in this study. In addition, strong motion duration does not have a significant influence on the amplitude of peak residual drift demands in MDOF systems, but records having long strong-motion duration tend to increase residual drift demands in the upper stories of long-period generic frames.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.194-202
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• 2019

Reliability analysis of the components frequently starts with the data that manufacturer provides. If enough failure data are collected from the field operations, the reliability should be recomputed and updated on the basis of the field failure data. However, when the failure time record for a component contains only a few observations, all statistical methodologies are limited. In this case, where the failure records for multiple number of identical components are available, a valid alternative is combining all the data from each component into one data set with enough sample size and utilizing the useful information in the censored data. The ROK Navy has been operating multiple Patrol Killer Guided missiles (PKGs) for several years. The Korea Multi-Function Control Console (KMFCC) is one of key components in PKG combat system. The maintenance record for the KMFCC contains less than ten failure observations and a censored datum. This paper proposes a Bayesian approach with a Dirichlet mixture model to estimate failure time density for KMFCC. Trends test for each component record indicated that null hypothesis, that failure occurrence is renewal process, is not rejected. Since the KMFCCs have been functioning under different operating environment, the failure time distribution may be a composition of a number of unknown distributions, i.e. a mixture distribution, rather than a single distribution. The Dirichlet mixture model was coded as probabilistic programming in Python using PyMC3. Then Markov Chain Monte Carlo (MCMC) sampling technique employed in PyMC3 probabilistically estimated the parameters' posterior distribution through the Dirichlet mixture model. The simulation results revealed that the mixture models provide superior fits to the combined data set over single models.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.318-323
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• 2008

A single specimen of the ophichthid Muraenichthys gymnopterus (254.6 mm TL) was collected from the middle Yellow Sea off Incheon, Korea. It represents the first record of the species, the genus, and the subfamily from Korea. This species is characterized by the following combination of characters: a constricted midlateral gill opening; dorsal fin origin before anus, closer to the anus than to the gill opening; blunt teeth, jaw teeth in bands, and multiserial dentition; third preopercular pore present; single infraorbital pore between anterior and posterior nostrils; brownish colour; depth and width of gill opening 43.2 times and 33.7~65.3 times in total length, respectively; eye diameter 15.0~31.0 times in head length and total vertebrae 154~161. New Korean names are proposed, "Gaet-mul-baem-a-gwa" for the subfamily Myrophinae, "Gaet-mul-baem-sok" for the genus Muraenichthys, and "Gaet-mul-baem" for M. gymnopterus.

• Journal of Information Display
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• v.12 no.2
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• pp.109-113
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• 2011

This paper summarizes the recent fabrication and characterizations of flexible high-speed radio frequency (RF) transistors, PIN-diode single-pole single-throw switches, as well as flexible inductors and capacitors, based on single-crystalline Si nanomembranes transferred on polyethylene terephthalate substrates. Flexible thin-film transistors (TFTs) on plastic substrates have reached RF operation speed with a record cut-off/maximum oscillation frequency ($f_T/f_{max}$) values of 3.8/12 GHz. PIN diode switches exhibit excellent ON/OFF behaviors at high RF frequencies. Flexible inductors and capacitors compatible with high-speed TFT fabrication show resonance frequencies ($f_{res}$) up to 9.1 and 13.5 GHz, respectively. Robust mechanical characteristics were also demonstrated with these high-frequency passives components.

• Korean Journal of Ichthyology
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• v.32 no.2
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• pp.110-114
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• 2020

A single specimen (40.5 mm in SL) of Clariger chionomaculatus was collected at 4 m depth on mud bottom from off Geojedo Island, Korea. This species is characterized by having an elongated body without scales, several barbels below eyes, I, 12~15 second dorsal fin rays, I, 12~14 anal fin rays; 19~20 pectoral fin rays with one free soft ray on upper part, and a unique color pattern with numerous white blotches on dorsal part of body. Because it has been known from Japan only to date, we describe in detail C. chionomaculatus as the first record from Korea. A new Korean name, "Huin-jeom-wae-mang-dug", is proposed for the species.

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.255-257
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• 2005

A single specimen (59.3 mm in SL) of the family Gobiesocidae was collected from the northern coast of Jeju Island, Korea. It was identified as Lepadichthys frenatus by its having dorsal and anal fins with 17 and 13 rays, respectively, both fins connected to the caudal fin, and a reddish-brown body color. We describe the specimen as the first record from Korea, and propose a new Korean name "keun-ip-hak-chi" for the species.

• Korean Journal of Ichthyology
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• v.20 no.3
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• pp.220-223
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• 2008

A single specimen (220.4 mm SL) of the bandfish Acanthocepola indica was collected near Maemul Island, off southeastern Korea. This species is characterized by having a serrated posterior margin of preopercle and a black blotch on anterior part of dorsal fin. It differs from two other species, A. limbata and A. krusensternii, in having a deeper body, 88 dorsal fin rays, and 101 anal fin rays. Our specimen of A. indica is the first record of the species from Korea, for which we propose the new Korean name "Nam-bang-hong-gal-chi."

• Korean Journal of Ichthyology
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• v.30 no.3
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• pp.175-180
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• 2018

A single bothid specimen (113.9 mm in standard length) was collected by bottom trawl from southern Jejudo Island, Korea. It was easily identified as Kamoharaia megastoma (Kamohara, 1936), based on extremely large mouth. The species is characterized by maxillary extending beyond eyes, three pairs of long curved canines on lower jaw, tip of vomer projecting into mouth cavity, blackish pectoral fin, and blind side without lateral line. We described it as the first record to Korean fish fauna, and proposed the new Korean name, "Keun-ip-dung-geul-neop-chi" for this species.

• Korean Journal of Ichthyology
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• v.28 no.2
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• pp.121-124
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• 2016

A single specimen of Ariosoma meeki, belonging to the family Congridae, was collected for the first time from Jinhae-gu, Changwon-si, Gyeongsangnam-do, Korea, on June 10, 2015. Ariosoma meeki is characterized by an absence of scales on its whole body, dorsal and anal fin connected to the caudal fin, blackish margins of the dorsal and anal fin, posterior nostrils not covered with a dermal flap, 60 preanal lateral-line pores, 15 pectoral fin rays, no cephalic sensory pore between the interorbital region and dorsal fin origin, and two dark brown dots behind the eyes. We described it as the new Korean record, and proposed the Korean name "nun-te-bung-jang-eo" for this species A. meeki.