• Progress in Superconductivity and Cryogenics
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• v.9 no.2
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• pp.1-6
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• 2007

As very sensitive magnetic field sensors, superconducting quantum interference devices (SQUIDs) are used to measure magnetic field signals from the human heart. By analyzing these cardiomagnetic signals, functional diagnoses of heart can be done. In order to measure weak biomagnetic signals, we need a multichannel SQUID array with sensor coverage large enough to cover the whole heart to enable the measurement in a single position setting. In this paper, we review the recent development of SQUID systems for measuring cardiomagnetic fields, with special emphasis on SQUID types.

• Progress in Superconductivity
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• v.9 no.1
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• pp.23-28
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• 2007

In order to have a superconductive connection between the wire-wound pickup coil and input coil, typically Nb terminal blocks with screw holes are used. Since this connection structure occupies large volume, large stray pickup area can be generated which can pickup external noise fields. Thus, SQUID and connection block are shielded inside a superconducting tube, and this SQUID module is located at some distance from the distal coil of the gradiometer to minimize the distortion or imbalance of uniform background field due to the superconducting module. To operate this conventional SQUID module, we need a higher liquid He level, resulting in shorter refill interval. To make the fabrication of gradiometers simpler and refill interval longer, we developed a novel method of connecting the pickup coil into the input coil. Gradiometer coil wound of 0.125-mm diameter NbTi wires were glued close to the input coil pads of SQUID. The superconductive connection was made using an ultrasonic bonding of annealed 0.025-mm diameter Nb wires, bonded directly on the surface of NbTi wires where insulation layer was stripped out. The reliability of the superconductive bonding was good enough to sustain several thermal cycling. The stray pickup area due to this connection structure is about $0.1\;mm^2$, much smaller than the typical stray pickup area using the conventional screw block method. By using this compact connection structure, the position of the SQUID sensor is only about 20-30 mm from the distal coil of the gradiometer. Based on this compact module, we fabricated a magnetocardiography system having 61 first-order axial gradiometers, and measured MCG signals. The gradiometers have a coil diameter of 20 mm, and the baseline is 70 mm. The 61 axial gradiometer bobbins were distributed in a hexagonal lattice structure with a sensor interval of 26 mm, measuring $dB_z/dz$ component of magnetocardiography signals.

• Journal of Food Hygiene and Safety
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• v.15 no.1
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• pp.18-24
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• 2000

In this study, ohmic heating was applied for pasteurization of red pepper pow-der, and investigated its pasteurization effect. After pasteurization, seasoned squid-jeotkal was manufactured by using red pepper powder, and its quality changes were investigated. On com-paring sensory evaluation in squid-jeotkal by pasteurized and conventional red pepper powder during storage at 5, 16 and $25^{\circ}C$, quality changes in squid-jeotkal by the pasteurized red pepper powder. But quality change difference between two products were decrease with increasing stor-age temperature. Viable cell counts in two products stored at 5$^{\circ}C$ were increased slowly until 60 days. Viable cell counts in squid-jeotkal by conventional red pepper powder were increased up to ca. 10$^{8}$ CFU/g at 15, 25 $^{\circ}C$ after 30, 15 days, respectively, but that by pasteurized were ca. 10$^{8}$ CFU/g at $25^{\circ}C$ after 30 days. Changes in pH, VBN and NH$_2$-N in two products were shown difference significantly, but were decreased by increasing storage temperature. In squid-jeotkal by conventional red pepper powder, the main free amino acids were glutamic acid, leucine, glycine, aspartic acid and alanine, and these amino acids held 47.95% of the total free amino acid. But in squid-jeotkal by pasteurized red pepper powder, glutamic acid, glycine, aspartic acid, leucine and Iysine, and these amino acids held 57.58% of the total free amino acids.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.3
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• pp.224-230
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• 2018

Squid is one of the important fisheries resources in Korea. Therefore, squid has been designated and managed as a target species of total allowable catch (TAC) since 2007, but the catch amount is gradually decreasing. The analysis was conducted to identify the change of relative fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the offshore squid jigging fishery from 1960s to 2010s. Gross tonnage per fishing vessel increased with the increase in size until 1990, but then gradually decreased to 41.0 tons in 2000 and 37.1 tons in 2010. The illuminating power (energy consumption) by fishing lamps increased to 180 kW in 2005 and stabilized to 120 kW in 2015. Jigging machine started to be supplied to fishing vessels from the early 1970s, and fish finders began to be supplied in the early 1980s and gradually increased. Therefore, the relative fishing power index in the offshore squid jigging fishery increased from 1.0 in 1980 to 1.1 in 1990, to 3.5 in 2000 and to 2.5 in 2010, but the increment rate slowed down gradually. The results are expected to contribute to reasonable fisheries stock management.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1654-1659
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• 2010

In order to utilize squid liver by-products, which is normally discarded as industrial waste in the process of squid manufacturing, salt-fermented squid liver sauce was prepared experimentally and also tested for inhibitory activity against angiotensin converting enzyme (ACE). ACE inhibitory activity of squid liver sauce was increased with the elapse of fermentation days until 12 months, followed by a constant level of inhibitory activity thereafter. 15-month-old sauce ($IC_{50}=29.66\;{\mu}g$) was filtered through PM-10 membrane (M.W. cut-off 10,000 Da) to obtain the peptides fractions with ACE inhibition activity. Filtered fractions were applied to a Bio-gel P-2 column and three active fractions (A, B and C) were collected. Among them, fraction B applied to a SuperQ-Toyopearl 650S column chromatography lead to the isolation of active B-1 fraction. It has the ACE inhibitory activity ($IC_{50}=5.46\;{\mu}g$). The main composition of its amino acids is lysine, glycine and proline, which cover about 85% of the total amino acids.

• Journal of the Korean Magnetics Society
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• v.6 no.4
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• pp.264-271
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• 1996

A magnetically shielded room has been constructed for biomagnetic applications. The room has internal dimensions of $2\;m(length){\times}2\;m(width){\times}2.5\;m(height)$ and it consists of high permeability Mumetal and high conductivity alummum, utilizing ferromagnetic shielding and eddy current shielding. The de shielding factor around the center of the room is above 60 dB, and the ac shielding factors at 1 and 10 Hz are larger than 60 and 80 dB, respectively. The internal magnetic field noise at 1 Hz is $500\;fT/{\sqrt}Hz$ and at 10 Hz is $100\;fT/{\sqrt}Hz$, and the field gradient noise at 1 Hz is below $7\;fT/cm{\sqrt}Hz$. Successful measurements of cardiomagnetic fields usmg SQUID magnetometer and neuromagnetic fields using SQUID gradiometer have been done.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.621-625
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• 2008

Squid oil is an abundant source of polyunsaturated fatty acids. This is particularly true for eicosapentaenoic acid and docosahexaenoic acid. The principal objective of this study was to extend the stability and improve the process aptitude of squid liver oil. Fluidized bed coatings were employed for coating with microencapsulated oil. The efficiency of the fluidized bed coating of the microencapsulated powder was over 90%. The apparent density with zein-DP was 0.6 g/mL, thereby indicating that flow ability had been improved as the result of an increase in specific gravity. The solubility of artificial gastric and enteric fluids with HPMC-FCC was 59.9 and 0%, respectively, whereas with zein-DP solubility was 0 and 31.0%, respectively. Polyunsaturated fatty acid retention results demonstrated that zein-DP coating was higher than HPMC-FCC, followed by the microencapsulated squid liver oil method. These results demonstrated that the application of microencapsulation and fluidized bed micro-coating techniques improved the stability and processing compatibility of squid liver oil.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.3
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• pp.276-280
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• 2016

This study investigated luring distributions by water layer of common squid which were targeted by angling fishing vessels equipped with LED and metal-halide lamps using a scientific echosounder with a 120 kHz frequency in order to develop energy-effective underwater fish aggregation devices. In the analysis, angles of a transducer were changed from $0^{\circ}$ to $45^{\circ}$ and were rotated every $10^{\circ}$ horizontally. It was shown that common squid were densely distributed from the surface to 40 m and they were also distributed in directions of $10^{\circ}{\sim}+30^{\circ}$, $-30^{\circ}{\sim}-60^{\circ}$, and $-120^{\circ}{\sim}-130^{\circ}$with the head of vessel as the center. Comparative results of angles of transducer on acoustical densities of common squid distributing in 21~40 m water depth showed an average $101.8m^2/nm^2$ in vertical direction of $0^{\circ}$, $12.3m^2/nm^2$ in angle of $30^{\circ}$, and $42.4m^2/nm^2$ in angle of $45^{\circ}$, respectively. It implied that more considerations on acoustic scattering strength by incidence angle direction of the transducer and swimming oriental angle direction of common squid would be required.

• Korean Journal of Poultry Science
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• v.31 no.1
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• pp.17-24
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• 2004

This study was performed to investigate the development of smoked chicken using old laying hens. Seventy two-weeks-old, spent laying hens were fed commercial feed (control) supplemented with 100 IU ${\alpha}$-tocopherol plus 10% squid liver oil (treatment) for 15 days and slaughtered. Smoked chickens were manufactured with spent laying hens in this study, Moisture and crude ash contents in smoked chicken of treatments were higher (P＜0.05) than those of control group due to the feeding 100 IU ${\alpha}$-tocopherol plus 10% squid liver oil. No differences were observed in fatty acid and amino acid composition between control and treatments. In sensory evaluation, the springiness of smoked chicken was evaluated optimum for 32% consumer. The elastic, blend, specific flavor and smell of the smoked chicken of the treatment were not different from those of the control. However, 46% of tested panel answered that the springiness was higher in the treated-group due to the feeding 100 IU ${\alpha}$-tocopherol plus 10% squid liver oil. These results indicated that smoked chickens would be developed with spent laying hen after feeding 100 IU ${\alpha}$-tocopherol plus 10% squid liver oil and sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.292-297
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• 1996

In this study, biochemical changes of muscle protein in squid Sikhae prepared at various temperatures and moisture content were investigated. The pH values in squid Sikhae decreased rapidly with increase in titratable acidity during fermentation at high temperature and moisture content. Growth rate of lactic acid bacteria increased rapidly during fermentation at high temperature and moisture content. Changes in muscle protein subunit were analyzed by SDS-PAGE; myosin heavy chain component disappeared completely during preparation of squid Sikhae and actin component decreased slowly during fermentation. Therefore, it was suggested that myosin heavy chain component in squid muscle protein was autolyzed at the incipient for-mentation time and actin component was degraded by acidic protease in muscle and protease produced from microorganisms during fermentation.