• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.5
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• pp.309-314
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• 2008

The toxicity of five species of puffer fish, Arothron firmamentum (Byeolbok), Lagocephalus gloveri (Heukmilbok), L. wheeleri (Eunmilbok), L. inermis (Minmilbok) and L. lunaris (Milbok), collected from fish markets in Korea, was determined using a mouse bioassay. In A. firmamentum, the proportion of toxic specimens containing >10 MU/g was 87.5% in the ovaries, and 10.0% in the skin; no toxicity was detected in the muscle, fin, liver, intestine and gallbladder using the mouse bioassay. The highest toxin levels were found to be 87 MU/g in the ovaries, and 13 MU/g in the skin. Toxic specimens containing >10 MU/g were not detected from samples taken from any of the organs in L. wheeleri and L. inermis. In L. gloveri, most specimens were found to be non-toxic, but toxin levels of 11-72 MU/g were detected from within the skin, fins, and intestines in one specimen. In L. lunaris, the proportion of toxic specimens was 50.0% in the ovaries, and 7.1% in the gallbladder; no toxicity was detected in the other organs by the mouse bioassay. The highest toxin levels were 75 MU/g in the ovaries, and 14 MU/g in the gallbladder. Therefore, the toxicities of edible muscle and skin in the five species of puffer fish marketed in Korea were found to be within acceptable levels for human consumption.

• Korean Journal of Ichthyology
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• v.7 no.2
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• pp.114-119
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• 1995

A flathead fish, collected from the water off Cheju lsland is tentatively identified as Inegocia guttata of the family Platycephalidae for the first time from Korea. Inegocia guttata is similar to Cymbacephalus beauforti in morphological characters, but differs from C. beauforti in lacking dermal flaps on eyes and having pored scales much fewer than oblique scales slanting backward and downward above the lateral line, single and tongue - like interopecular flap, nasal spines and circled blackish spots in the pectoral and ventral fins. A new Korean name, "Akoyangtae", is proposed for the I. guttata.

• Korean Journal of Ichthyology
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• v.7 no.2
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• pp.101-108
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• 1995

Four specimens of Megalaspis cordyla(Linnaeus) belonging to the family Carangidae and three specimens of Champsodon snyderi Franz belonging to the family Champsodontidae were collected for the first time from Nam-hae and Pusan, Korea. Megalaspis cordyla is similar to other genera, but differs in some morphological charac-ters : the presence of finlets, the beginning portion and shape of scutes, and the length of pec-toral fin. A new Korean name "Ko-d$\breve{u}$ng-ka-ra-ji" is proposed for the M. cordyla. Champsodon snyderi is differs from C. capensis in the number of pectoral fins and the pres-ence of scale on cheek ; from C. longipinnis in having a pale spinous dorsal fin ; from C. guen-theri and C. machaeratus in having 11 lower gill rakers, 19 soft dorsal fin rays. A new Korean name "Ak-$\hat{o}$-chi" is proposed for the C. snyderi.

• Journal of the Korean Solar Energy Society
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• v.30 no.5
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• pp.56-62
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• 2010

The integration of PV modules into building facades or roof could raise their temperature that results in the reduction of PV system's electrical power generation. Hot air can be extracted from the space between PV modules and building envelope, and used for heating in buildings. PV/thermal collectors, or more generally known as PVT collectors, are devices that operate simultaneously to convert solar energy from the sun into two other useful energies, namely, electricity and heat. This paper compares the experimental performance of BIPVT((Building-Integrated Photovoltaic Thermal) collectors that applied on building roof and facade. There are four different cases: a roof-integrated PVT type and a facade-integrated PVT type, the base models with an air gap between the PV module and the surface, and the improved models for each types with aluminum fins attached to the PV modules. The accumulated thermal energy of the roof-integrated type was 15.8% higher than the facade-integrated regardless of fin attachment. The accumulated electrical energy of the roof-integrated type was 7.6% higher, compared to that of the facade-integrated. The efficiency differences among the collectors may be due to the fact that the pins absorbed heat from the PV module and emitted it to air layer.

• Journal of Fisheries and Marine Sciences Education
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• v.6 no.1
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• pp.58-76
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• 1994

Heat transfer and pressure drop measurements are made on low integral-fin tubes in turbulent water flow condition. The integral-fin tubes investigated in this paper are nominally 19mm in diameter. Eight tubes have been used with trapezoidally shaped integral-fins having fin density from 748 to 1654 fpm and 10, 30 grooves. Plain tube having same diameter as finned tube is also tested for comparison. Experiments are carried out using R-11 as working fluid. The refrigerant condensates at a saturation state of $30^{\circ}C$ on the outside tube surface cooled by coolant. The amount of noncondensable gases present in the test loop is reduced to a negligible value by repeated purging. For a given heat input to the boiler and given cooling water flow rate, all test data are taken on steady state. The heat transfer loop is used for testing single long tubes and cooling water is pumped from a storage tank through filters and flowmeters to the horizontal test section where it is heated by steam condensing on the outside of the tube. The pressure drop across the test section is measured by means of pressure gauge and manometer. Each tube tested is cleaned with sodium dichromate pickling solution and well rinsed with water prior to installation in the test section. The results obtained in this study is as follows : 1. Based on inside diameter and nominal inside area, heat transfer of finned tube is enhanced up to 4 times as that of a plain tube at constant Reynolds number and up to 2 times at constant pumping power. 2. Friction factors are up to 1.6~2.1 times those of plain tube. 3. At a given Reynolds number, Nusselt number decrease with increasing pitch to diameter. 4. The constant pumping power ratio for low integral-fin tubes increase directly with the effective area to the nominal area ratio, and with the effective area diameter ratio.

• Journal of Fisheries and Marine Sciences Education
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• v.9 no.2
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• pp.167-178
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• 1997

It has been expected not only for crew but also for passengers to realize a ship whose rolling and other motions are small as much as possible. Restricting our consideration to the roll reduction, the conventional roll stabilization system, fins or anti-rolling tanks hve been utiized as the actuator. Excessive motions would interfere with the recreational activities of passengers on a cruise ship. Often more than half of the load of a containership is stowed above deck where it is subjected to large acclerations due to rolling. In some situations this may cause some internal damage to the contents of the containers; in more severe situations failure of the lashing can occur and containers may be lost over-board. Underdeck cargo in ordinary cargo ships and bulk commodities in colliers, ore ships and grain ships can shift if the motions become too severe. The purpose of this study is to concentrate on the additions. either internal or external to the hull, that reduce or otherwise improve the motion responses of the hull. It is assumed that the additions are such that their benefit to the motions of the ship outweights any impact on the ability of the ship to perform its assigned task. It is particularly challenging to obtain large improvements in the motion characteristics of existing ships that are being rebuilt or modified for some task not anticipated in their original design. Further the authors will statistically analyze the influence of ruder-roll-yaw coupling motion in the case of application of this advanced control method to various kinds of ship.

• Journal of the Korean Society for Nondestructive Testing
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• v.17 no.3
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• pp.156-161
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• 1997

The eddy current probe was designed for the test of fin tubes that have uneven outer and inner surfaces to enhance the efficiency of heat emission. Because of the surface roughness of the fin tube, it needs much care to detect flaws in the tube employing eddy current test(ECT). We made ECT probes with different coil lengths and performed eddy current test using these probes for artificially flawed specimens. By the fast Fourier transform and digital filtering, signals from these probes were processed to characterize frequency spectra. From the analysis of eddy current signals and their frequency spectra, we concluded that, for the effective testing of the tubes with the fins of 1mm pitch, 4mm coil length gave the highest S/N ratio.

• Korean Journal of Ichthyology
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• v.10 no.2
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• pp.260-267
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• 1998

Three species of the order Perciformes collected from coastal waters of Cheju Island, Korea were documented with photographs, all of which are newly known to Korea. Nemipterus bathybius Snyder, 1911 of the family Nemipteridae is distinguished by seven anal soft rays and the most upper ray at the caudal fin elongated. Cirrhitichthys aureus (Temminck et Schlegel, 1842) of the family Cirrhitidae (New Korean name: Hwangbokdom-kwa), is characterized by the five to six light black spots on the dorso-Iateral sides, 12 dorsal soft rays and a dorsal fin without spots and bands. Parapercis aurantiaca D$\ddot{o}$erlein, 1884 of the family Pinguipedidae, has several taxonomic characters. The dorsal spines and the soft rays of the dorsal fins were connected without a notch. The five to six dark yellow bands with the same size of eye length were shown on the lateral region. A new Korean name Kinsilkkoridom is proposed for the Nemipterus bathybius, and Cirrhitichthys aureus, Hwangbukdom, and Parapercis aurantiaca, Hwangssangdonggari.

• Korean Journal of Ichthyology
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• v.27 no.3
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• pp.238-242
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• 2015

Three specimens (56.7~92.4 mm in standard length) of the small psychrolutid Psychrolutes pustulosus (Schmidt, 1937) were collected by bottom trawl in the coastal waters off Pohang, the southern East Sea, Korea. This species is characterized by large cephalic pores, no markings on the body or fins, no spines on the head, and no notch between the spiny and soft-rayed dorsal fin. We describe specimens the southernmost distribution in the world, and compare them with two congeneric species from Russia. We thus present the first record of Psychrolutes pustulosus (Schmidt, 1937) within the Korean fish fauna and propose the new Korean name "Min-mu-nui-mul-su-bae-gi" for this species.

• Korean Journal of Ichthyology
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• v.28 no.2
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• pp.72-78
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• 2016

The age and spawning characteristics of Iksookimia pacifica were investigated in this study to provide baseline data for its ecological characteristics in the Bukcheon (stream), Goseong-gun, Gangwon-do, Korea from January to December, 2013. Age groups of I. pacifica (female) estimated by the frequency distribution of total length in the spawning season indicated that the 30~49 mm group is 1 year old, the 50~74 mm group is 2 years old, the 75~99 mm group is 3 years old, the 100~124 mm group is 4 years old, and the 130~160 mm group is $5{\leq}$years old. The sex ratio (♂/♀) was 0.63, and females were 30~60 mm larger than males. The lamina circularis at the base of pectoral fins in males as a secondary sexual character was created at the 13th month after hatching. The spawning season according to the gonadosomatic index (GSI) was July to August (main spawning season in July) with water temperatures of $20{\sim}25^{\circ}C$. The average number of eggs was $2,503{\pm}1,337$ with a diameter of $1.11{\pm}0.04mm$ in mature eggs.