• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.3
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• pp.227-237
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• 2013

In Jeju Island, red sea bream is mainly caught by long line with a live squid as bait. The movements of artificial jigs in the fishery are supposed to be an important factor for catching the target organism as well as bait. To develop new fishing method for long line fishery, movements of the bait which was squid were tried to be characterized. In a water tank experiment, a live squid was hooked by a fish hook attached to a model long line. And then movements of squids in the water tank were recorded for 20 minutes by a video camera. Recorded movement of the squid was just periodically up-and-down moving, with a dominant frequency of 0.125Hz, and amplitude of 10.8cm.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.437-442
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• 1996

High quality $YBa_2Cu_3O_y$(YBCO) thin films for directly coupled dc superconducting quantum interference device (SQUID) were fabricated by pulsed laser deposition. Several critical parameters have been optimized through systematic studies. Thus, the films showing the $T_c$ of above 91K and $J_c$ of above$2\times10^6A/cm^2$ at 77K were routinely obtained. Extensive AFM and X-ray diffraction studies have been conducted for morphological and structural analyses. The directly coupled DC-SQUIDs were fabricated from the YBCO thin films deposited on $SrTiO_3$ bicrystals under the optimized conditions. The measurement on $2I_c$ and swing voltage give 200$\mu$A and 17$\mu$V at 77K, respectively.

• Preventive Nutrition and Food Science
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• v.1 no.2
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• pp.196-202
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• 1996

The effect of cooking(boiling, steaming and baking0and drying on the cholesterol content and formation of oxidized cholesterols in quid(Japanese flying squid, Todarodes pacificus) was studied. Cholesterol content of live squid meat varied with the portion sampled, and results from spectrophotometric assay ranged from 263.2mg/1..g(mantle) to 315.8mg/100g(tentacle). The cholesterol levels analyzed by gas chromatography(GC) for squid samples were lower by 7% of total cholesterol for live squid meat and 24% for processed meat than those results by spectrophotometric assay. Cooking resulted in the decrease of the initial total cholesterol content of raw meat from 10%(boiling for 5min.) to 25%(steaming for 5min.) The amounts of cholesterol remaining after baking were 68% for microwave oven samples and 64% for convection oven samples. Drying of raw tissue caused the greater reduction in cholesterol content than cooking but showed no significant difference in samples stored for 6 weeks at 4$^{\circ}C$ and 2$0^{\circ}C$. Raw squid meats contained essentially no oxidized cholesterols, while the 22-hydroxychoesterol was detected in frozen meats. The additional oxidized cholesterols as cholestane-triol was indentified with 22-hydroxycholesterols in cooked samples. Sun dried meat stored at 4一 and 2$0^{\circ}C$ for 6 weeks had the three kinds of oxidized cholesterols such as 22-hydroxycholesterol, cholesta-3,5-dien-7-one and cholestane-triol.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.1
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• pp.78-89
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• 2008

This study is intended to analyse the economic sensitivity of imported fishery products due to decrease in or elimination of tariff rates through the progress of free trade. Forty-seven species of fishes were selected for this study on the basis of the HS Code. The substitution and price effects were calculated using the price elasticities of both domestic and imported demands for fishery products under the assumption of 5% decrease in a tariff rate. Seven main economic variables were extracted from the fishery industry which can mediate the substitution and price effects. A multiple regression analysis was conducted to obtain the influence weights of these main economic variables on both effects. The order of sensitivity of the fishes was calculated using these weights. The 47 fish species were classified into four groups according to their sensitivity based on the means and the standard deviations of their total scores on seven main economic considerations. Nine fish species such as squids, hair tails, shellfishes, and crabs belonged to the hyper-sensitive group, whereas 15 fishes such as eels, sea breams, and sea weeds belonged to the sensitive group. Twelve species including common sea basses, cods, and abalones were among the less-sensitive group, and 11 species including skate rays and mud fishes comprised the non-sensitive group.

• Progress in Superconductivity
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• v.6 no.1
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• pp.19-23
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• 2004

YBCO do superconducting quantum interference device (SQUID) magnetometers based on bicrystal Josephson junctions on 10 mm ${\times}$ 10 mm $SrTiO_3$ substrates have been fabricated. The pickup coil of the device was designed to have 16 parallel loops with 50-fm-wide lines. We could obtain optimised direct coupled YBCO SQUID magnetometer design with field sensitivity $B_{N}$ $\Phi$/ of $4.5 nT/\Phi_{0}$ and magnetic field noise $B_{N}$ of about $22 fT/Hz^{1}$2/ with an I/f corner frequency of 2 Hz measured inside a magnetically shielded room. Preliminary results of magnetocardiograph measurement using the HTS SQUID magnetometers show signal to noise ratio of about 110, which is comparable to the quality of a commercial MCG system based on Nb-SQUIDs.

• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.191-197
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• 1999

Stomach contents of hairtail, Trichiurus lepturus collected in the Nakdong River Estuary were examined quantitatively. T. lepturus was a carnivore which consumed mainly fishes, crustaceans (such as copepods, euphausiids and shrimps) and chaetognaths. Its diets included small quantities of small squids. T. lepturus showed ontogenetic progression of three feeding stages : an initial feeding stage was a planktivorous stage in which copepods were the major food item, followed by a mixed feeding stage in which euphausiids, mysids, shrimps, chaetognaths and fishes were the major food items, and finally a piscivorous stage in which fishes were the major food item. Especially anchovies were heavily selected by large T. lepturus.

• Korean Journal of Ichthyology
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• v.12 no.1
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• pp.54-61
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• 2000

Feeding habits of Zoarces gilli collected in the coastal water off Gadeok-do, Korea from March 1998 to February 1999 were studied. Z. gilli was a carnivore and consumed mainly shrimps, gammarid amphipods, fishes, bivalves and cumaceans. Its diets also included small quantities of copepods, caprellid amphipods, ostracods, crabs, squids, gastropods, ophiuroids and polychaetes. It showed ontogenetic changes in feeding habits. Individuals of small size (10~15 cmSL) fed mainly on small prey organisms such as gammarid amphipods, bivalves, cumaceans and ostracods. However, larger shrimps and fishes were heavily selected with increasing fish size.

• Journal of Sensor Science and Technology
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• v.13 no.2
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• pp.110-113
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• 2004

We have designed and fabricated the YBCO single layer directly-coupled SQUID magnetometers for the purpose of magnetocardiography in a magnetically disturbed environment. The SQUID magnetometers were designed three different types of pickup coil such as solid type, PL type I and PL type II for further stable fluxed-locked-loop operation without magnetic shielding. Magnetometer was fabricated with a single layer YBCO thin film deposited on STO(100) bicrystal substrate with misorientation angle of $30^{\circ}$. We have achieved a magnetic field noise BN of 30 fT/$Hz^{1/2}$ at 100 Hz, and less than 70 fT/$Hz^{1/2}$ at 1 Hz. The PL type II SQUIDs have exhibited the most stable fluxed-locked-loop operation in a magnetically unshielded environment.

• 한국해양학회지
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• v.30 no.3
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• pp.197-202
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• 1995

A total of 272 specimens of Todarodes pacificus purchased during the period from July 1 to August 30, 1994 in the southern sea off Pusan were examined for their infection status with larval anisakids. Larvae in squids were encapsulated and appeared to remain active. Firty five larval anisakids sorted from T. pacificus (7.72% of infection rate) were classified based on morphological and morphometric observations as follows; Anisakis type I larvae (23 larvae, 51.0%: positive rate), Contracaecum type A (9, 20.0%), Contracaecum D (4, 9.0%), Anisakis II (3, 6.7%) and unknown type (6, 13.3%).

• Progress in Superconductivity
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• v.2 no.1
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• pp.20-26
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• 2000

A 40-channel superconducting quantum interference device (SQUID) system was constructed for measuring neuromagnetic fields. Main features of the system are the use of double relaxation oscillation SQUIDs (DROSs), and planar gradiometers measuring magnetic field components tangential to the head surface. The DROSs with high flux-to-voltage transfers enabled direct readout of the SQUID output by room-temperature dc preamplifiers and simple flux-locked loop circuits could be used for SQUID operation. The pickup coil is an integrated first-order planar gradiometer with a baseline of 40 mm. Average noise level of the 40 channels is around 1.2 $fT/cm/{\surd}Hz$ at 100 Hz, corresponding to a field noise of 5 $fT/{\surd}Hz$, operated inside a magnetically shielded room. The SQUID insert was designed to have low thermal load, minimizing the loss of liquid helium. The constructed system was applied to measure auditory-evoked neuromagnetic fields.