• 한국임상수의학회지
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• 제38권2호
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• pp.75-81
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• 2021

An aquariid nematode, Desportesius invaginatus, was found in the proventriculus of an Egretta garzetta and a Bubulcus ibis from Chuncheon in the Republic of Korea. The worms were identified by light and scanning electron microscopy based on important taxonomic characteristics (body length, esophagus length, cordons, spicules, caudal alae of males, position of the vulva) and then phylogenetically analyzed using the 18S rRNA encoding gene. The nematodes were characterized by a body length of 7.0-8.0 mm in males and 10.2-13.1 mm in females, and two pairs of cordons recurrent in the anterior direction, and cordons were anastomosed by a longitudinal cuticular ridge that externally delimits a longitudinal canal. The widest cuticular plates of cordons bears over 20 posterior spines. The length of the spicules in males was also significantly different. The right spicule measured 742-821 (794) ㎛ in length and 40-45 (42) ㎛ in width, and the left spicule measured 493-556 (541) ㎛ in length and 11-13 (12) ㎛ in width. The caudal alae of males are inflated and vesicular in appearance. The vulva was situated at 56-71 (58.3) ㎛ from the posterior extremity. Although the 18S rRNA sequences of worms were similar to the Synhimantus species, some genetic divergences were observed in comparison. In this study, the worms were recognized with genus Desportesius because genus Desportesius was considered a subgenus of Synhimantus. This is the first record of D. invaginatus in the Republic of Korea.

• 한국작물학회지
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• 제43권3호
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• pp.161-167
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• 1998

Root and shoot development of two rice (Oryza sativa L.) cultivars with different genetic backgrounds was studied with reference to their relative growth. Tongil type (indica-japonica hybrid) cultivar 'Kuemkangbyeo' and japonica cultivar 'Koshihikari' were grown in $5000^{-1}$ a Wagnar pots under flooded condition. Three plants with roots of both cultivars were taken in every phyllochron through the heading stage to record morphological characteristics of shoot and root system. Compared to Koshihikari, Kuemkangbyeo produced more tillers and had greater shoot weight and leaf area per hill. Length and weight of the root system in both cultivars increased exponentially with time. At the same time, root system development was significantly faster in Kuemkangbyeo than in Koshihikari after the panicle initiation stage. As a result, Kuemkangbyeo has a vigorous root system which consists of larger number of nodal roots compared to Koshihikari. Also, the root length and weight per unit leaf area of Kuemkangbyeo were larger than those of Koshihikari in the later half of growing period, which suggests possible higher physiological activity of the root system of Kuemkangbyeo which is known as a high-yielding cultivar. The relationship between root traits (crown root number, total root length, and root dry weight) and shoot traits (leaf area and leaf+culm dry weight) in both cultivars closely showed allometry until the flag leaf stage.

• 천문학회지
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• 제41권3호
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• pp.77-81
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• 2008

As a continuation of a previous work by Park et al. (2006), we have developed a two-element radio interferometer that can measure both the phase and amplitude of a visibility function. Two small radio telescopes with diameters of 2.3 m are used as before, but this time an external reference oscillator is shared by the two telescopes so that the local oscillator frequencies are identical. We do not use a hardware correlator; instead we record signals from the two telescopes onto a PC and then perform software correlation. Complex visibilities are obtained toward the sun at ${\lambda}\;=\;21\;cm$, for 24 baselines with the use of the earth rotation and positional changes of one element, where the maximum baseline length projected onto UV plane is ${\sim}\;90{\lambda}$. As expected, the visibility amplitude decreases with the baseline length, while the phase is almost constant. The image obtained by the Fourier transformation of the visibility function nicely delineates the sun, which is barely resolved due to the limited baseline length. The experiment demonstrates that this system can be used as a "toy" interferometer at least for the education of (under)graduate students.

• Applied Microscopy
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• 제50권
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• pp.18.1-18.7
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• 2020

The olfactory anatomy and histology of Lethenteron reissneri were researched using a stereo microscope, a light microscope, and a scanning electron microscope. As in other lampreys, it shows same characters as follows: i) a single olfactory organ, ii) a single tubular nostril, iii) a single olfactory chamber with gourd-like form, iv) a nasal valve, v) a nasopharyngeal pouch, vi) a sensory epithelium (SE) of continuous distribution, vii) a supporting cells with numerous long cilia, viii) an accessory olfactory organ. However, the description of a pseudostratified columnar layer in the SE and Non SE is a first record, not reported in sea lamprey Petromyzon marinus. In particular, both 19 to 20 lamellae in number and olfactory receptor neuron's quarter ciliary length of the knob diameter differ from those of P. marinus. From these results, it might be considered that the olfactory organ of L. reissneri shows well adaptive structure of a primitive fish to slow flowing water with gravel, pebbles, and sand and a hiding habit into sand bottom at daytime. The lamellar number and neuron's ciliary length may be a meaningful taxonomic character for the class Petromyzonida.

• 한국어류학회지
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• 제27권1호
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• pp.55-59
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• 2015

이악어목, 붉평치과에 속하는 Lampris guttatus 1개체(표준체장 705 mm)가 2014년 11월 12일 삼척 연안의 정치망에서 처음으로 채집되었다. 이 종은 체고가 높고 난형인 점, 지느러미와 턱이 선명한 진홍색인 점 그리고 몸 전체에 흰 반점이 불규칙하게 흩어져 있는 점이 특징이다. 이 미기록종의 과명과 속명 그리고 종명은 "붉평치과", "붉평치속" 그리고 "붉평치"로 각각 제안하였다.

• 한국어류학회지
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• 제27권1호
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• pp.45-49
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• 2015

돔발상어목 Somniosidae에 속하는 Somniosus pacificus 1개체가 2008년 2월 강원도 강릉해역에서 채집되었다. 본 종은 두 등지느러미 사이의 길이가 주둥이에서 첫 번째 새열까지의 길이보다 짧으며, 주둥이에서 첫 번째 등지느러미 사이의 길이가 전장의 45%를 넘고 몸은 전체적으로 잿빛을 띠는 특징을 가진다. 우리나라에서 처음 보고되는 본 종의 새로운 과명, 속명 및 종명으로 "잠상어과", "잠상어속" 및 "잿빛잠상어"를 제안한다.

• 한국어류학회지
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• 제21권4호
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• pp.307-310
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• 2009

한국산 바다뱀과 어류에 포함되는 Pisodonophis cancrivorus(체장 862.3 mm) 1 개체가 경상북도 울진군 북면 연안에서 2008년 9월에 채집되었다. 본 종의 특징은 후비공 전후에 근육돌기가 1개씩 나 있고, 상악치를 비롯하여, 하악치와 서골치가 과립상으로 무질서하게 3~5줄로 된 치판을 형성하고 있으며, 등지느러미는 가슴지느러미의 중앙 상부에서 출발하는 점이다. 본종은 상악의 후비공 전후에 근육돌기가 있는 점을 들어 국명을 "돌기바다뱀"이라고 명명하였다.

• 한국기계가공학회지
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• 제17권2호
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• pp.109-117
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• 2018

The experimental results are presented of an autonomous flight algorithm of a foldable quadcopter with airdrop launching functions. A foldable wing structure enabled the quadcopter to be inserted into a rocket container with limited space. The foldable quadcopter was then separated from the rocket in the air. The flight pattern was tracked using a global positioning system (GPS) with various sensors, including an inertial measurement unit (IMU) module until a designated target position was reached. Extensive field tests were conducted through an international rocket competition, ARLISS 2017, which was held in Black Rock Desert, Nevada, USA. The flight trajectory record of the experiments is stored in electrically erasable programmable read-only memory (EEPROM) embedded in the main control unit. The flight record confirmed that the quadcopter successfully separated from the rocket, executed flight toward the target for a certain length of time, and stably landed on the ground.

• Animal Systematics, Evolution and Diversity
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• 제9권1호
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• pp.51-59
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• 1993

1984년 8월ㅇ부터 1986년 8월가지 제주도 성산포와 부산시 해운대 연안에서 채집한 망둑어 과 어류 가운데 전장 22.0~38.8mm의 359개체를 조사한 결과 한국산 미기록종인 Parioglossus dotui Tomiyams로 동정되었다. 본 종은 소형으로 배지느러미가 좌우로 분리되어 있으나, 새조골이 5개로 망둑어아과 Gobiinae에 속한다. 꼬리지느러미 기저와 접하는 곳에 암색반문이 있어 다른 종과 구별되고, 체측의 비늘은 납작한 돌 모양으로 붙어 있다. 주로 연안의 하천 기수역에 서식하면서 집단으로 유영생활을 한다. 본 종의 한국명은 동설망둑 속 "동설망둑"으로 명명한다. 그 결과 한국산 망둥어 과 어류는 1속 1종이 추가되어 총 34속 56종이 된다.

• Fisheries and Aquatic Sciences
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• 제17권2호
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• pp.263-267
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• 2014

A single juvenile pomacentrid specimen (5.9 mm standard length) was collected from the Korea Strait in October 2010. The specimen is characterized by punctate-stellate melanophores scattered on the operculum and dorso-ventral region in front of the caudal peduncle, the lack of melanophores on the posterior end of the anal fin base, the presence of 14 spines and 14 soft rays on the dorsal fin, and the presence of 2 spines and 12 soft rays on the anal fin. A molecular analysis based on mitochondrial DNA 16S rRNA sequences showed that this specimen is closely related to adult Chromis mirationis (d = 0.002), but that it differs from Chromis notata (d = 0.017). Juvenile C. mirationis differ from juvenile C. notata in having no melanophores on the posterior end of the anal fin base. We propose a new Korean name, "tti-ja-ri-dom" for C. mirationis.