• Ocean Science Journal
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• v.41 no.4
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• pp.201-205
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• 2006

Larval specimens of Halicampus punctatus were collected off Ulsan and Uljin in December 2002 (three specimens) and off Ulsan in December 2003 (one specimen). These specimens are characterized by the following morphological characteristics: rings, 14 + 35 = 49; subdorsal rings, 1 + 3 = 4; dorsal fin rays, 19 - 20; pectoral fin rays, 14 - 15; anal fm rays, 9; head length (HL), 5.8 - 6.7 in the standard length; snout length, 1.9 in HL; snout depth, 3.7 - 5.2 in snout length. The number of caudal fin rays 9 is less than those of the other species in the same genus 10. Wide stripe bands composed of small pigments are shown in the trunk and the tail. Melanophores are not found in the dorsal fin, the pectoral fin, and the anal fin except the caudal fin. The supraoccipital crest is on the head. The frontal ridge is on the dorsal side of front trunk. The blanched ridges on the opercular are fused with a main ridge like a tree branch. A few branched ridges that are small and narrow on the trunk and the tail are fused with the main ridges. We report these specimens as the first record in Korea and name them 'Byeol-sil-go-ki' in Korean.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.593-598
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• 2005

At-site analysis is not appropriate if the record length is shorter than target return period T. If the record length is longer than 27 years, then at-site analysis may be sufficient(Institute of Hydrology, 1999). However, in such a case, regional frequency analysis is recommended for purpose of comparison. Record lengths of annual maximum rainfall data in Korea are usually shorter than 50 years. It is therefore essential to apply regional frequency analysis for estimating rainfall quantiles of more than 100 years return period. In this research, regional rainfall frequency analysis is performed for hourly rainfall data of South Korea. Homogeneous regions are idntified by clusgter analysis which is a standard method of statistical multivariate analysis for dividing a data set into groups. An appropriate distribution is chosen by goodness-of-fit test. GLO is found to be an appropriate distribution as a result of goodness-of-fit measure (Hosking & Wallis, 1997). Simulation experiments are performed to check the performance of frequency analysis techniques. The effects of discordant sites on quantiles are considered.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.2
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• pp.189-194
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• 2022

Unidentified postflexion larva (18.57 mm in standard length, SL), belonging to the family Synodontidae was collected from Jeju Island, Korea, in November 2019. Molecular analysis revealed that the unidentified larva was identical to Synodus kaianus adults in mtDNA cytochrome c oxidase subunit I region (Kimura-2-parameter distance, d= 0.006), and was different from the close species S. macrops (d=0.220). The postflexion larva of S. kaianus has the following morphological features: regularly distributed seven peritoneal pigment spots along the alimentary canal; and, intensively distributed stellate melanophores at the middle of the base of caudal fin and behind the last anal fin ray. The postflexion larva of S. kaianus differed from that of S. macrops in snout length and size of peritoneal pigment spots. This is the first record of S. kaianus in Korea, and we suggest the Korean name "Ka-i-ya-kkoch-dong-myeol" for S. kaianus, according to Lee et al. (1999).

• Bulletin of the Korean Mathematical Society
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• v.58 no.2
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• pp.433-444
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• 2021

In this paper a new generating procedure of a random chord is presented. This problem has its roots in the Bertrand's paradox. A study of the limit behaviour of its maximum length and the rate of convergence is conducted. In addition, moments of record values of random chord length are obtained for this case, as well as other cases of solutions of Bertrand's paradox.

• Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.283-286
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• 2015

This is the first report of Pterygotrigla multiocellata from the family Triglidae, collected in Korea. The specimen (314 mm in standard length) was caught in a gill net in the coastal waters of Jeju Island on 11 February 2010. This species is characterized by the following morphological traits: head large and triangular, bony plates absent along the base of the second dorsal fin, antrorse rostral spine long, and cleithral spine long. We suggest a new Korean name, "Gin-ppul-mit-seong-dae" for P. multiocellata.

• Journal of Species Research
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• v.5 no.3
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• pp.539-540
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• 2016

Microturbellarians, small free-living Platyhelminthes are rich in freshwater environments. They are useful as indicator of water quality. There has never been a record of microturbellarians in Korea. Here I report a microturbellarian species, Catenula confusa Nuttycombe, 1956. Although specimens in this study show some differences with those of the original description of C. confusa in length and width of zooid, they conform to the specific diagnosis of this species.

• Journal of KSNVE
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• v.11 no.3
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• pp.455-460
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• 2001

An exact spectrum wish no leakage error could be obtained when the period of the signal coincides perfectly with the record length. However, the record length will be determined regardless of the period of signal. The Leakage error due to this problem will gibe a distorted spectrum. In the conventional research, the method was proposed to estimate the three parameters, frequency, amplitude and phase angle, from the spectrum data for anundamped sinusoidal signal. In this paper, some techniques are proposed to estimate frequency, amplitude and damping ratios from the frequency response functions for damped signals. The validation of the proposed techniques is verified by several numerical examples.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.517-522
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• 2002

The frequency response function(FRF) of each substructure is used for the transfer function synthesis method(TFS). The dynamic characteristics of the full system are obtained by synthesizing FRFs of each substructure. The validation of TFS depends on accuracy for FRF of each substructure. Impact hammer testing is widely used to obtain the modal characteristics of structures. However, the FRF obtained from impact hammer testing contains several errors, such as finite record length error and leakage error of which characteristic depends on data acquisition time which we call record length. In this paper, a method to remove these errors is proposed so as to enhance results of TFS. Numerical examples show that the FRF of full structure can be predicted exactly by the method proposed in this paper.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.589-593
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• 2017

A single specimen of Kentrocapros flavofasciatus (measuring 145.9 mm in length) belonging to the family Aracanidae, order Tetraodontiformes, was collected for the first time in 2017 on Jeju Island, Korea. This specimen had isolated bony plates on a caudal peduncle, a carapace with six ridges, and a tail depth equal to its tail length. It is similar to K. aculeatus and K. rosapinto but differs from K. aculeatus in that its carapace is without spines; it differs from K. rosapinto in that the anterior end of its gill opening does not reach below the center of its eye. We propose new Korean names: Yug-gak-bok-gwa for the family Aracanidae, and Hwang-Jul-yug-gak-bok for the species K. flavofasciatus.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.408-413
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• 2003

The frequency response function(FRF) of each substructure is used for the transfer function synthesis method(TFS). The dynamic characteristics of the full system are obtained by synthesizing FRFs of each substructure. The validation of TFS depends on accuracy for FRF of each substructure. Impact hammer testing Is widely used to obtain the modal characteristics of structures However. the FRF obtained from impact hammer testing contains bias errors, such as finite record length error and leakage error of which characteristic depends on data acquisition time which we call record length. In this paper, a method to remove hose errors is proposed so as to enhance results of TFS. Numerical and experimental examples show that the FRF of full structure can be predicted nearly exactly by the method proposed in this paper.