• Title/Summary/Keyword: ocean

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Prelaunch Study of Validation for the Geostationary Ocean Color Imager (GOCI) (정지궤도 해색탑재체(GOCI) 자료 검정을 위한 사전연구)

  • Ryu, Joo-Hyung;Moon, Jeong-Eon;Son, Young-Baek;Cho, Seong-Ick;Min, Jee-Eun;Yang, Chan-Su;Ahn, Yu-Hwan;Shim, Jae-Seol
    • Korean Journal of Remote Sensing
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    • v.26 no.2
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    • pp.251-262
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    • 2010
  • In order to provide quantitative control of the standard products of Geostationary Ocean Color Imager (GOCI), on-board radiometric correction, atmospheric correction, and bio-optical algorithm are obtained continuously by comprehensive and consistent calibration and validation procedures. The calibration/validation for radiometric, atmospheric, and bio-optical data of GOCI uses temperature, salinity, ocean optics, fluorescence, and turbidity data sets from buoy and platform systems, and periodic oceanic environmental data. For calibration and validation of GOCI, we compared radiometric data between in-situ measurement and HyperSAS data installed in the Ieodo ocean research station, and between HyperSAS and SeaWiFS radiance. HyperSAS data were slightly different in in-situ radiance and irradiance, but they did not have spectral shift in absorption bands. Although all radiance bands measured between HyperSAS and SeaWiFS had an average 25% error, the 11% absolute error was relatively lower when atmospheric correction bands were omitted. This error is related to the SeaWiFS standard atmospheric correction process. We have to consider and improve this error rate for calibration and validation of GOCI. A reference target site around Dokdo Island was used for studying calibration and validation of GOCI. In-situ ocean- and bio-optical data were collected during August and October, 2009. Reflectance spectra around Dokdo Island showed optical characteristic of Case-1 Water. Absorption spectra of chlorophyll, suspended matter, and dissolved organic matter also showed their spectral characteristics. MODIS Aqua-derived chlorophyll-a concentration was well correlated with in-situ fluorometer value, which installed in Dokdo buoy. As we strive to solv the problems of radiometric, atmospheric, and bio-optical correction, it is important to be able to progress and improve the future quality of calibration and validation of GOCI.

Effects of Dietary Inclusion of Soybean Meal and Fermented Soybean Meal on Growth and Body Composition of Juvenile Abalone Haliotis discus (Reeve 1846) (배합사료내 대두박 및 발효대두박 첨가가 까막전복(Haliotis discus) 치패의 성장과 체조성에 미치는 영향)

  • Kim, Hee Sung;Jeong, Hae Seung;Choi, Dong Gyui;Jang, Bok-Il;Kim, Hyeon Jong;Lee, Ki Wook;Cho, Sung Hwoan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.6
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    • pp.812-817
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    • 2017
  • This study evaluated the effects of dietary inclusion of soybean (SM) and fermented soybean meal (FSM) on growth promotion in juvenile abalone Haliotis discus. Six hundred and thirty juvenile abalone were distributed into nine plastic containers. Three diets were prepared with 22% fish meal, 2% casein, and either 25% SM or FSM used as the protein sources in the experimental diets, and Undaria was used as a control diet to compare the effects of the experimental diets on the growth performance of abalone. The diets were assigned to three containers each and fed to the abalone once daily to satiation for 16 weeks. Weight gain and specific growth rate (SGR) were higher in abalone fed the SM diet than in those fed the FSM diet. Weight gain and SGR of abalone fed the SM and FSM diets were higher than those of abalone fed Undaria. The crude protein and lipid contents of the edible portions of abalone fed the SM and FSM diets were higher than those of abalone fed Undaria. SM was superior to FSM as a protein source in abalone feed. The SM and FSM diets facilitated greater growth than Undaria.

Single Nucleotide Polymorphisms of the GnRHR Gene Associated with Reproductive Traits of Japanese Flounder (Paralichthys olivaceus)

  • He, Feng;Wen, Hai-Shen;Li, Ji-Fang;Yu, Da-Hui;Ma, Rui-Qin;Shi, Dan;Mu, Wei-Jie;Zhang, Yuan-Qing;Hu, Jian;Liu, Miao;Han, Wei-Guo;Zhang, Jia-Nan;Wang, Qing-Qing;Yuan, Yu-Ren;Liu, Qun
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.4
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    • pp.463-470
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    • 2011
  • Gonadotropin-releasing hormone receptor (GnRHR) gene is expressed at the anterior pituitary gland and plays a key role in gonad development. This study aimed to investigate molecular genetic characteristics of the GnRHR gene and elucidate the effects of single nucleotide polymorphisms (SNPs) of GnRHR gene on sex steroid level in Japanese flounder (Paralichthys olivaceus). We used polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and sequencing of the GnRHR gene in 75 individuals. We identified three SNPs in the GnRHR gene: P1 locus (C759A and C830T) in the coding region of exon2 which were both linked together and P2 locus (G984T) in the coding region of exon3, which added a new transcript factor (ADR1) and a new methylation site (CG). Only C830T of P1 leads to amino acid changes Thr266Ile. Statistical analysis showed that P1 was significantly associated with $17{\beta}$-estradiol ($E_2$) level (p<0.01) and gonadosomatic index (GSI) (p<0.05). Individuals with genotype BB of P1 had significantly higher serum $E_2$ levels (p<0.01) and GSI (p<0.05) than those of genotype AA or AB. Another SNP, P2, synonymous mutation, was significantly associated with GSI (p<0.05). Individuals with genotype AB of P2 had significantly higher GSI (p<0.05) than that of genotype AA. In addition, there was a significant association between one diplotype based on three SNPs and reproductive traits. The genetic effects for both serum $E_2$ level and GSI of diplotype D4 were super diplotypes (p<0.05). These results suggest that the SNPs in Japanese Flounder GnRHR are associated with $E_2$ level and GSI.

Application of DINEOF to Reconstruct the Missing Data from GOCI Chlorophyll-a (GOCI Chlorophyll-a 결측 자료의 복원을 위한 DINEOF 방법 적용)

  • Hwang, Do-Hyun;Jung, Hahn Chul;Ahn, Jae-Hyun;Choi, Jong-Kuk
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1507-1515
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    • 2021
  • If chlorophyll-a is estimated through ocean color remote sensing, it is able to understand the global distribution of phytoplankton and primary production. However, there are missing data in the ocean color observed from the satellites due to the clouds or weather conditions. In thisstudy, the missing data of the GOCI (Geostationary Ocean Color Imager) chlorophyll-a product wasreconstructed by using DINEOF (Data INterpolation Empirical Orthogonal Functions). DINEOF reconstructs the missing data based on spatio-temporal data, and the accuracy was cross-verified by removing a part of the GOCI chlorophyll-a image and comparing it with the reconstructed image. In the study area, the optimal EOF (Empirical Orthogonal Functions) mode for DINEOF wasin 10-13. The temporal and spatialreconstructed data reflected the increasing chlorophyll-a concentration in the afternoon, and the noise of outliers was filtered. Therefore, it is expected that DINEOF is useful to reconstruct the missing images, also it is considered that it is able to use as basic data for monitoring the ocean environment.

Estimation of Wave Loads Acting on Stationary Floating Body Using Viscous Numerical Wave Tank Technique (점성 수치파랑수조 기술을 이용한 고정된 부유체의 파랑하중 산정)

  • Kim, Kyung-Mi;Heo, Jae-Kyung;Jeong, Se-Min;Park, Jong-Chun;Kim, Wu-Joan;Cho, Yong-Jin
    • Journal of Ocean Engineering and Technology
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    • v.27 no.3
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    • pp.43-52
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    • 2013
  • In the present study, a flow analysis for estimating the wave loads acting on a stationary floating body inside a viscous numerical wave tank was performed using the commercial software FLUENT. The governing equations for the viscous and incompressible fluid motion were the continuity and Navier-Stokes equations, and a piston-type wavemaker was employed to reproduce wave environments. First, the optimal simulation conditions were derived through numerical tests for the wavemaker and wave absorber, and then the wave loads and wave run-up on a vertical truncated cylinder were estimated and compared with the experimental and other numerical results.

Induced Morphological Changes in Larval Rock Bream, Oplegnathus fasciatus, under Starvation

  • Park, In-Seok;Choi, Hee-Jung;Noh, Choong-Hwan;Myoung, Jung-Goo;Park, Hye Jung;Goo, In Bon
    • Development and Reproduction
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    • v.17 no.4
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    • pp.399-407
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    • 2013
  • Morphological changes in the reared rock bream, Oplegnathus fasciatus, from hatching to six days after hatching were examined during the early growth stage under starvation. All the larvae died within five days when feeding was delayed for three days after hatching. These results imply that initial larval food should be supplied within two days of hatching. Changes in the pectoral angle and the ratios of eye height to head height, gut height to standard length, and gut height to myotome height in the rock bream are alternative indicators for the identification of starving fish. These indicators might prove useful in evaluating the successful transition from endogenous to exogenous feeding in this species.