• Title/Summary/Keyword: squid

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Nondestructive Evaluation System using SQUID in Magnetically Un-shielded Environment (비자기 차폐 환경에서의 SQUID를 이용한 비파괴 평가 시스템에 대한 연구)

  • Chung, Soon-Hee;Hwang, Yun-Seok;Choi, Hee-Seok;Kim, Jin-Tae;Lim, Hae-Ryong;Kim, In-Seon;Kwon, Hyuk-Chan;Park, Yong-Ki;Park, Jong-Chul;Lee, Soon-Gul;Lee, Dong-Hoon;Kim, Dong-Ho
    • 한국초전도학회:학술대회논문집
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    • v.9
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    • pp.54-57
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    • 1999
  • 본 연구에서는 SQUID를 이용한 비파괴 평가 시스템을 제작, 측정하였다. 이 시스템은 비자기 차폐 환경에서 작동할 수 있도록 설계하였고, 측정 자기 센서로는 dc 및 rf-SQUID gradiometer를 사용하였다. 비자기 차폐 환경에서 ${\sim}$nT의 미세 자기 신호를 검출하였고, 공간적으로 변화하는 외부 자기 신호를 측정, 분석하였다. 또한, 측정된 자기 신호를 통해 dc-SQUID와 rf-SQUID에 대한 비교를 했다.

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Construction and Operation of a 40-channel SQUID System for Neuromagnetic Measurements (40-채널 SQUID 시스템의 제작 및 뇌자도 측정)

  • Lee, Yong-Ho;Kim, Jin-Mok;Kwon, Hyuk-Chan;Lee, Sang-Kil;Lim, Cheong-Moo;Park, Yong-Ki;Park, Jong-Chul
    • 한국초전도학회:학술대회논문집
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    • v.9
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    • pp.27-32
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    • 1999
  • We developed a 40-channel superconducting quantum interference device (SQUID) system for neuromagnetic measurements. The main features of the system are use of double relaxation oscillation SQUID (DROS), and planar gradiometer for measuring tangential field components. The DROSS with high flux-to-voltage transfers enabled direct readout of the SQUID output by room-temperature electronics 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. The average noise of the 40 channels is around 1.2 fT/cm/${\sqrt{Hz}}$ at 100 Hz, corresponding to the field noise of 5 fT/${\sqrt{Hz}}$ at 100 Hz, operated inside a magnetically shielded room. The 40-Channel system was applied to measure auditory-evoked neuromagnetic fields.

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Effects of Gamma Irradiation on Taste Compounds in Processing of Low Salted and Fermented Squid (감마선 이용 저염 오징어젓갈 제조시 정미성분의 변화)

  • 변명우;이경행;김재훈;이주운;이은미;김영지
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.5
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    • pp.1051-1057
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    • 1999
  • The effects of gamma irradiation on taste compounds of low salted and fermented squid were investig ated. Salted and fermented squid products were prepared with salt concentrations of 5%, 10%, and 20% and was fermented at 15oC and 25oC after gamma irradiation with a dosage of 2.5~10 kGy. Amino nitrogen (AN), volatile basic nitrogen(VBN), trimethylamine(TMA), and hypoxanthine(Hx) contents were examined during the fermentation periods. Results showed that gamma irradiation had no effect on the initial con tents of AN, VBN, TMA, and Hx compared with non irradiated salted and fermented squid. During the fermentation periods, these contents rapidly increased in accordance with the decrease in NaCl concen tration and irradiation dose, and the increase in fermentation temperature. Specifically, the taste compounds of salted and fermented squid prepared with a NaCl concentration of 10% and an irradiation dose of 10 kGy maintained the appropriate level for the fermentation period at 15oC.

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YBCO step-edge junction dc SQUID magnetometers with multi-loop pickup coil fabricated on sapphire substrates (사파이어 기판을 사용한 병렬 검출코일 구조의 계단형 모서리 접합 SQUID 자력계)

  • 황태종;김인선;김동호;박용기
    • Progress in Superconductivity
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    • v.5 no.2
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    • pp.94-97
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    • 2004
  • Step-edge Josephson junctions (SEJ) have been fabricated on sapphire substrates with in situ deposited films of CeO$_2$ buffer layer and YBa$_2$Cu$_3$O$_{7}$ films on the low angle steps. Direct coupled SQUID magnetometers with the SEJ were formed on 1 cm X 1 cm R-plane sapphire substrates. Typical 5-${\mu}{\textrm}{m}$-wide Josephson junctions have R$_{N}$ of 3 Ω and I$_{c}$ of 50 $mutextrm{A}$ at 77 K. The direct coupled SQUID magnetometers were designed to have pickup coils of 50-${\mu}{\textrm}{m}$-wide 16 parallel loops on the 1 cm X 1 cm substrates with outer dimension of 8.8 mm X 8.8 mm. The SEJ SQUID magnetometers exhibit relatively low 1/f noise even with dc bias control, and could be stably controlled by flux-locked loops in the magnetically disturbed environment. Field noise of the do SQUID was measured to be 200∼300 fT/Hz$^{1}$2/in the white noise region and about 2 pT/Hz$^{1}$2/ at 1 Hz when measured with dc bias method.hod.d.

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Construction of a 40-channel SQUID System and Its Application to Neuromagnetic Measurements

  • Lee, Y.H.;Kim, J.M.;Kwon, H.C.;Park, Y.K.;Park, J.C.;Lee, D.H.;Ahn, C.B.
    • 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.

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Characteristics of periodical movement of live squid (Todarodes pacificus) hooked on the branch line of a red sea bream long line

  • Koo, Myung Sung;Ishizaki, Munechika;Kim, Suk Jong;Fuwa, Shigeru;Archdale, Miguel Vazquez
    • 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.

Stability of Antioxidant Properties and Essential Amino Acids in Squid Viscera Hydrolysate Produced using Subcritical Water

  • Kim, Ryoung-Hee;Asaduzzaman, A.K.M.;You, Chi-Hong;Chun, Byung-Soo
    • Fisheries and Aquatic Sciences
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    • v.16 no.2
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    • pp.71-78
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    • 2013
  • Subcritical water hydrolysis was carried out in a batch reactor to produce valuable materials, such as low-molecular weight (MW) peptides and essential amino acids with antioxidant properties, from heat-dried squid viscera. Hydrolysis of squid viscera was performed at 160 to $280^{\circ}C$ for 3 min. The yield was increased by increasing the temperature and pressure, while the protein content of squid viscera hydrolysate decreased with increasing temperature. Low-MW peptides were detected in all hydrolysates by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The highest yields of free and structural amino acids in heat-dried squid viscera hydrolysate were at $160^{\circ}C$ and were $411.95{\pm}1.15$ and $346.62{\pm}1.25$ mg/100 g, respectively. All essential amino acids were detected in viscera hydrolysates; leucine was the most abundant. Antioxidant activities of hydrolysates were highest at $220^{\circ}C$. Greater than $98{\pm}0.26%$ of the ABTS antioxidant activity was retained in hydrolysates after long-term heat treatment.

Feeding Habits of Todarodes pacificus (Cephalopods: Ommastrephidae) in the Coastal Waters of Busan, Korea (부산 주변 해역에서 채집된 살오징어(Todarodes pacificus)의 식성)

  • Song, Hye-Jin;Baeck, Gun-Wook;Kim, Su-Am;Huh, Sung-Hoi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.39 no.1
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    • pp.42-48
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    • 2006
  • Analysis of stomach content for common squid was carried out to investigate the difference in seasonal and ontogenetic feeding behavior. Totals of 1368 common squid were collected monthly off Busan from September 2004 to August, 2005. Size range of common squid was 8.5-31.8 cm mantle length (ML) during the study period. Of the 1368 stomachs examined, 599 specimens (43.8%) were empty. Stomach contents indicated that common squid was carnivore: Large portion of stomach contents consisted of fish and mollusca (mainly common squid). The stomach contents index (SCI) seemed to increase with size, though there was no statistical difference between size classes significantly. Cannibalism was minimum in size range of 15-20 cm ML, but was steadily increased with size. Cephalopods were the major prey during spring and summer when common squid were small, but fish replaced it during autumn and winter when they became large.

The Sensory and Texture Characteristics of Inkyrice Cake in According to Concentrations of Squid Ink (오징어 먹물 첨가량에 따른 먹물떡의 기호도 및 품질 특성)

  • 임영희;김미원;김애정;김명희
    • Journal of the East Asian Society of Dietary Life
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    • v.9 no.4
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    • pp.468-474
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    • 1999
  • To make rice cake with squid ink, the squid ink dilulted in fifteen times was added to rice flour in the ratio of 0%, 2%. 4%, 6% and 8% respectively. Then, the squid inky rice cake was tested in physical function and chromaticity. Rheometer test was also included in this experiment. In physical function test, it showed that the inky rice cake with 6% and 8% ratio was the best in preference. In the chromaticity test, as the adding ratio of squid ink increases, the brightness decreased. The red and yellow brightness of 8% inky rice cake showed high. The results of rheometer test are as follows. In hardness, the inky rice cake with 2% adding ratio was high and the 6% inky rice cake was low. In cohesiveness, the 0% inky rice cake was high and the 8% inky rice cake was low. In gumminess, the 2% inky rice cake was high and the 6% inky rice cake was low. In brittleness, the 2% inky rice cake was high and the 6% inky rice cake was low. With correlation analysis, 1 could reach the following. The overall quality of inky rice cake was correlated with all test items except chewiness. The moistness was correlated with flavor, grain and chewiness. Also, the 8% inky rice cake was correlated with the inky rice cakes with the other adding ratios in all aspects of test. Futhermore, in the results of rheometer test. the hardness was correlated with the other three kinds of characteristics.

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The Thronging of Shoals of Squid to Audible underwater Sound (가청 수중음에 대한 오징어 어군의 위집)

  • 서두옥
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.3
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    • pp.220-227
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    • 1995
  • An underwater speaker was designed and used as sound source for thronging shoal of squid in squid angling gear operation. The frequency characteristics of the designed speaker was analyzed experimentally and the thronging response of shoals of squid which may be a key parameter for a new sound catching method, was characterized in audible frequency. The field experiment was carried out in the coast of Cheju Island. The results of this study are summarized as follows; 1. Amplitude response of the speaker shows a maximum in their the frequency of 500Hz. 2. The output waveform distortion is not measured in the frequency range of 250~600Hz. 3. A underwater noise of shoals of squid which were thronged by fish lamp in night appeared the center frequency of 300~400Hz. 4. The shoals of squid shows a thronging response, when a manufactured underwater speaker transmits a intermittent audible sound of 300~400Hz in 10m depth of water.

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