In the present article, we introduce a high resolution sea surface temperature （SST） product generated daily by Korea Institute of Ocean Science and Technology （KIOST）. The SST product is comprised of four sets of...In the present article, we introduce a high resolution sea surface temperature （SST） product generated daily by Korea Institute of Ocean Science and Technology （KIOST）. The SST product is comprised of four sets of data including eight-hour and daily average SST data of I km resolution, and is based on the four infrared （IR） satellite SST data acquired by advanced very high resolution radiometer （AVHRR）, Moderate Resolution Imaging Spectroradiometer （MODIS）, Multifunctional Transport Satellites-2 （MTSAT-2） Imager and Meteorological Imager （MI）, two microwave radiometer SSTs acquired by Advanced Microwave Scanning Radiometer 2 （AMSR2）, and WindSAT with in-situ temperature data. These input satellite and in-situ SST data are merged by using the optimal interpolation （OI） algorithm. The root-mean-square-errors （RMSEs） of satellite and in-situ data are used as a weighting value in the OI algorithm. As a pilot product, four SST data sets were generated daily from Ianuary to December 2013. In the comparison between the SSTs measured by moored buoys and the daily mean KIOST SSTs, the estimated RMSE was 0.71~C and the bias value was -0.08~C. The largest RMSE and bias were 0.86 and -0.26~C respectively, observed at a buoy site in the boundary region of warm and cold waters with increased physical variability in the Sea of Iapan/East Sea. Other site near the coasts shows a lower RMSE value of 0.60~C than those at the open waters. To investigate the spatial distributions of SST, the Group for High Resolution Sea Surface Temperature （GHRSST） product was used in the comparison of temperature gradients, and it was shown that the KIOST SST product represents well the water mass structures around the Korean Peninsula. The KIOST SST product generated from both satellite and buoy data is expected to make substantial contribution to the Korea Operational Oceanographic System （KOOS） as an input parameter for data assimilation.展开更多
The Fukushima nuclear accident in 2011 released large amounts of radionuclides, including ^（137）Cs, into the Pacific Ocean. A quasi-global ocean radioactive transport model with horizontal grid spacing of 0.5°&...The Fukushima nuclear accident in 2011 released large amounts of radionuclides, including ^（137）Cs, into the Pacific Ocean. A quasi-global ocean radioactive transport model with horizontal grid spacing of 0.5°×0.5° and 21 vertical layers was thereafter established to study the long-term transport of the Fukushima-derived ^（137）Cs in the ocean.The simulation shows that the plume of ^（137）Cs would be rapidly transported eastward alongside the Kuroshio Current and its extensions. Contaminated waters with concentrations lower than 2 Bq/m3 would reach the west coast of North America 4 or 5 years after the accident. The ^（137）Cs tends to be carried, despite its very low concentration, into the Indian and South Pacific Oceans by 2016 via various branches of ocean currents.Meanwhile, the ^（137）Cs concentrations in the western part of the North Pacific Ocean decrease rapidly with time. Up to now the highly contaminated waters have remained in the upper 400 m, showing no evidence of significant penetration to deeper layers.展开更多
A standard skill assessment （SA） tool was developed and implemented to evaluate the performance of op- erational forecast models in the Korea operational oceanographic system. The SA tool provided a robust way to as...A standard skill assessment （SA） tool was developed and implemented to evaluate the performance of op- erational forecast models in the Korea operational oceanographic system. The SA tool provided a robust way to assess model skill in the system by comparing predictions and observations, and involved the com- putation of multiple skill metrics including correlation and error skills. User- and system-based acceptance criteria of skill metrics were applied to determine whether predictions were acceptable for the system. To achieve this, the tool produced a time series comparison plot, a skill score table, and an advanced sum- marized diagram to effectively demonstrate the multiple skill scores. Moreover, the SA was conducted to evaluate both atmospheric and hydrodynamic forecast variables. For the atmospheric variables, acceptable error criteria were preferable to acceptable correlation criteria over short timescales, since the mean square error overwhelmed the observation variance. Conversely, for the hydrodynamic variables, acceptable root mean square percentage error （e.g., perms） criteria were preferable to acceptable error （e.g., erms） criteria owing to the spatially variable tidal intensity around the Korean Peninsula. Furthermore, the SA indicated that predetermined acceptance error criteria were appropriate to satisfy a target central frequency （fc） for which errors fell within the specified limits （i.e., the .fc equals 70%）.展开更多
A bstract The venerid clam(M actra veneriformis Reeve 1854) is one of the main cultured bivalve species in intertidal and shallow subtidal ecosystems along the west coast of Korea. To understand the effects of ocean a...A bstract The venerid clam(M actra veneriformis Reeve 1854) is one of the main cultured bivalve species in intertidal and shallow subtidal ecosystems along the west coast of Korea. To understand the effects of ocean acidifi cation on the early life stages of Korean clams, we investigated shell growth and abnormality rates and types in the D-shaped, umbonate veliger, and pediveliger stages of the venerid clam M. veneriformis during exposure to elevated seawater pCO_2. In particular, we examined abnormal types of larval shell morphology categorized as shell deformations, shell distortions, and shell fi ssures. Specimens were incubated in seawater equilibrated with bubbled CO_2-enriched air at(400±25)×10^(-6)(ambient control),(800±25)×10^(-6)(high pCO_2), or(1 200±28)×10^(-6)(extremely high pCO_2), the atmospheric CO_2 concentrations predicted for the years 2014, 2084, and 2154(70-year intervals; two human generations), respectively, in the Representative Concentration Pathway(RCP) 8.5 scenario. The mean shell lengths of larvae were signifi cantly decreased in the high and extremely high pCO_2 groups compared with the ambient control groups. Furthermore, under high and extremely high pCO_2 conditions, the cultures exhibited signifi cantly increased abundances of abnormal larvae and increased severity of abnormalities compared with the ambient control. In the umbonate veliger stage of the experimental larvae, the most common abnormalities were shell deformations, distortions, and fi ssures; on the other hand, convex hinges and mantle protuberances were absent. These results suggest that elevated CO_2 exerts an additional burden on the health of M. veneriformis larvae by impairing early development.展开更多
Quaternary intraplate magmatism formed several volcanic islands and seamounts,including Dokdo(DD),Ulleungdo(UD),Simheungtack(ST),Anyongbok,and Isabu in the southwest of the East Sea back-arc basin.In this study,we pre...Quaternary intraplate magmatism formed several volcanic islands and seamounts,including Dokdo(DD),Ulleungdo(UD),Simheungtack(ST),Anyongbok,and Isabu in the southwest of the East Sea back-arc basin.In this study,we present whole-rock geochemical,zircon U–Pb age,and in situ O–Hf isotope data for the submerged volcanic rocks from DD,UD,and ST to provide new insights into the eruption timing of these volcanoes and constrain the magma evolution processes.All samples used in this study were trachytes and exhibited ferroan,alkalic,and metaluminous to weakly peraluminous characteristics.They showed light rare earth element(REE)-enriched patterns with(La/Yb)N ratios of 25.3–31.7 and mostly negative Eu anomalies in a chondrite-normalized REE plot.In addition,they were enriched in large-ion lithophile elements and high field strength elements;they exhibited positive Pb anomalies and strongly negative Ba,Sr,P,and Ti anomalies.The zircons yielded a weighted-mean 206Pb/238U age of 2.61,0.348–0.704,and 2.76–2.94 Ma for the DD,UD,and ST trachytes,respectively.All zircons exhibited lowerδ^(18)O values than normal depleted mantle values,regardless of the crystallization age and spatial distribution of volcanoes.Theδ^(18)O values showed no correlation with U contents or Th/U ratios,indicating that the lowδ^(18)O signatures were of primary magmatic origin.The Hf isotopic compositions of the zircons were relatively heterogeneous but predominately characterized by positive eHf values.Binary O–Hf mixing modeling revealed that low-δ^(18)O rocks with positive eHf values from the UD and ST volcanoes were derived from a hybrid source of recycled juvenile crustal materials with low-δ^(18)O and positive eHf signatures and an enriched mantle source with normalδ^(18)O and negative eHf values.The juvenile oceanic crust in the source was likely metasomatized by seawater at high temperatures prior to melting.In contrast,the felsic magma that formed the DD volcanoes may have assimilated with regional basement rocks(Triassic–Jurassic granitoids),resulting in increasedδ^(18)O values and decreased eHf values relative to those of the UD and ST volcanoes.Our study highlights the significant contribution of recycled oceanic crust materials to the generation of the Quaternary magmas.展开更多
This study presents the concentration of radon-222(Rn)in bottom seawater and seawater 10 m above the seabed in the central Yellow Sea,where CO_(2) geological storage is considered.Five sampling points were selected,co...This study presents the concentration of radon-222(Rn)in bottom seawater and seawater 10 m above the seabed in the central Yellow Sea,where CO_(2) geological storage is considered.Five sampling points were selected,considering the locations of the buried faults possibly acting as migration pathways of injected CO_(2).The Rn concentrations of bottom seawater range from 0 to 26±10 Bq m-3,whereas those of seawater 10 m above the seabed range from 0 to 16±6 Bq m-3.The variation of Rn diffusion from the seabed accounts for different Rn concentrations at each sampling point.Based on CTD and sediment core data,it was found that the study area was characterized by summer stratification,muddy surface sediment,and homogeneous sediment resuspension profile above the seabed.These observations suggest that the Rn diffusion from the seabed varied insignificantly in the study area.Relatively high Rn concentrations were found in sampling points near the buried faults,implying that the location of the buried faults is critical as monitoring target.Although limited by the lack of sampling points,this study provides baseline Rn concentrations,which will help to implement a CO_(2) monitoring program in the central Yellow Sea.展开更多
Side-scan sonar(SSS)is essential for acquiring high-resolution seafloor images over large areas,facilitat-ing the identification of subsea objects.However,military security restrictions and the scarcity of subsea targ...Side-scan sonar(SSS)is essential for acquiring high-resolution seafloor images over large areas,facilitat-ing the identification of subsea objects.However,military security restrictions and the scarcity of subsea targets limit the availability of SSS data,posing challenges for Automatic Target Recognition(ATR)research.This paper presents an approach that uses Cycle-Consistent Generative Adversarial Networks(CycleGAN)to augment SSS images of key subsea objects,such as shipwrecks,aircraft,and drowning victims.The process begins by constructing 3D models to generate rendered images with realistic shadows frommultiple angles.To enhance image quality,a shadowextractor and shadow region loss function are introduced to ensure consistent shadowrepresentation.Additionally,amulti-resolution learning structure enables effective training,even with limited data availability.The experimental results show that the generated data improved object detection accuracy when they were used for training and demonstrated the ability to generate clear shadow and background regions with stability.展开更多
Tropical cyclones(TCs)are complex and powerful weather systems,and accurately forecasting their path,structure,and intensity remains a critical focus and challenge in meteorological research.In this paper,we propose a...Tropical cyclones(TCs)are complex and powerful weather systems,and accurately forecasting their path,structure,and intensity remains a critical focus and challenge in meteorological research.In this paper,we propose an Attention Spatio-Temporal predictive Generative Adversarial Network(AST-GAN)model for predicting the temporal and spatial distribution of TCs.The model forecasts the spatial distribution of TC wind speeds for the next 15 hours at 3-hour intervals,emphasizing the cyclone's center,high wind-speed areas,and its asymmetric structure.To effectively capture spatiotemporal feature transfer at different time steps,we employ a channel attention mechanism for feature selection,enhancing model performance and reducing parameter redundancy.We utilized High-Resolution Weather Research and Forecasting(HWRF)data to train our model,allowing it to assimilate a wide range of TC motion patterns.The model is versatile and can be applied to various complex scenarios,such as multiple TCs moving simultaneously or TCs approaching landfall.Our proposed model demonstrates superior forecasting performance,achieving a root-mean-square error(RMSE)of 0.71 m s^(-1)for overall wind speed and 2.74 m s^(-1)for maximum wind speed when benchmarked against ground truth data from HWRF.Furthermore,the model underwent optimization and independent testing using ERA5reanalysis data,showcasing its stability and scalability.After fine-tuning on the ERA5 dataset,the model achieved an RMSE of 1.33 m s^(-1)for wind speed and 1.75 m s^(-1)for maximum wind speed.The AST-GAN model outperforms other state-of-the-art models in RMSE on both the HWRF and ERA5 datasets,maintaining its superior performance and demonstrating its effectiveness for spatiotemporal prediction of TCs.展开更多
The Yellow Sea Cold Water Mass （YSCWM） is one of the important water mass in the Yellow Sea （YS）. It is distributed in the lower layer in the Yellow Sea central trough with the temperature less than 10℃ and the s...The Yellow Sea Cold Water Mass （YSCWM） is one of the important water mass in the Yellow Sea （YS）. It is distributed in the lower layer in the Yellow Sea central trough with the temperature less than 10℃ and the salinity lower than 33.0. To understand the variability of the YSCWM, the hydrographic data obtained in April and August during 2009-2011 are analyzed in the southeastern Yellow Sea. In August 2011, relatively warm and saline water compared with that in 2009 and 2010 was detected in the lower layer in the Yellow Sea central area. Although the typhoon passed before the cruise, the salinity in the Yellow Sea central trough is much higher than the previous season. It means that the saline event cannot be explained by the typhoon but only by the intrusion of saline water during the previous winter. In April 2011, actually, warm and saline water （T 〉 10~C, S 〉34） was observed in the deepest water depth of the southeastern area of the Yellow Sea. The wind data show that the northerly wind in 2011 winter is stronger than in 2009 and 2010 winter season. The strong northerly wind can trigger the intrusion of warm and saline Yellow Sea Warm Current. Therefore, it is proposed that the strong northerly wind in winter season leads to the intrusion of the Yellow Sea Warm Current into the Yellow Sea central trough and influenced a variability of the YSCWM in summer.展开更多
To investigate the distribution, abundance, and species composition of dinoflagellate cysts in the Yellow Sea, surface sediment samples were collected at 37 sites, including the Korean dump site. Twenty-one di- noflag...To investigate the distribution, abundance, and species composition of dinoflagellate cysts in the Yellow Sea, surface sediment samples were collected at 37 sites, including the Korean dump site. Twenty-one di- noflagellate cyst taxa were identified, with the assemblages dominated mainly by Spiniferites bulloideus, Operculodinium centrocarpum, and cyst of Alexandrium catenella/tarnarense type. A high frequency of O. centrocarpum in the Yellow Sea was observed for the first time, and it is likely that this can be attributed to the dynamics of the Yellow Sea Cold Water Mass and the Changjiang （Yangtze） River runoff. Total cyst concentrations ranged from 23 to 48 442 cysts/g dry weight, and high cyst concentrations were recorded adjacent to the dumping site. This result suggests that anthropogenic activities such as ocean dumping s- timulate the growth of dinoflagellates in the Yellow Sea, which in turn leads to high levels of dinoflagellate cyst production.展开更多
Objecive:To screen the fatty acid(FA) composition of 20 marine microalgae species,including seven Diophyceae,six Bacillariophyeae four Chlorophyceae,two Haptophyceae and one Raphidophyceae species.Methods:Microalgal c...Objecive:To screen the fatty acid(FA) composition of 20 marine microalgae species,including seven Diophyceae,six Bacillariophyeae four Chlorophyceae,two Haptophyceae and one Raphidophyceae species.Methods:Microalgal cells cultured at the Korea Institute of Ocean Science & Technology were harvested during the late exponential growth phase and the FA composition analyzed.Results:The FA composition of microalgae was speciesspecific.For example,seven different species of Dinophyceae were composed primarily of C14:0,C16:0.C18:0.C20:4n-6.C20:5n-3 and C22:6n-3.while C14:0.C16:0,C16:1.C18:0.C20:5n-3 and C22:6n-3 were abundant FAs in six species of Bacillariophyceae.In addition,four Chlurophyceae,two Haptopkyeeae and one Raphidophyceae species all contained a high degree of C16:1 n-7[(9.2R-34.91)%and(34.48-35.04)%].C14:0[(13.34-25.96)%]and[(26.69-Z8.24)%],and C16:0[(5.89-29.15)%]and[(5.70-16.81)%].Several factors contribute to the nutritional value of microalgae.including the polyunsaturated FA content and n-3 to n-6 FA ratio,which could be used to assess the nutritional quality of microalgae.Conclusions:This study is the first comprehensive assessment of the FA composition and nutritional value of microalgae species in South Korea,and identifies the potential utility of FAs as species-specific biomarkers.展开更多
Objective: To determine skin whitening and wrinkle improvement efficacy, glycoprotein fractions were extracted from liquid extracts of boiled sea cucumber and their effects on tyrosine and elastase inhibitory activiti...Objective: To determine skin whitening and wrinkle improvement efficacy, glycoprotein fractions were extracted from liquid extracts of boiled sea cucumber and their effects on tyrosine and elastase inhibitory activities were assayed. Methods: Fractions above and below 50 k Da(>50 kD a and <50 kD a) were extracted via a series of steps invovling: boiling, filtering, desalting and freeze drying. Cytotoxicity, skin whitening and wrinkle-removing effects of boiled liquid were determined. Results: Our MTT data showed that neither glycoprotein fraction of boiled liquid induces cellular cytotoxicity up to a concentration of 10 mg/m L treatment of the mouse melanoma cell line, B16F10, with 10 mg/m L >50 kDa enhanced tyrosinase and elastase inhibitory activities by 50.84% and 28.78%, respectively. Correlations of the >50 kD a concentration with tyrosinase inhibitory(R^2=0.968) and elastase inhibitory(R2=0.983) efficacy were significant. Conclusions: >50 kD a glycoprotein fraction isolated from liquid extracts of boiled sea cucumber, which can serve as a functional cosmetic ingredient for whitening and wrinkle improvement of skin.展开更多
Ice krill is the keystone species in the neritic ecosystem in the Southern Ocean, where it replaces the more oceanic Antarctic krill. It is essential to understand the variation of target strength （TS in dB re l m^2...Ice krill is the keystone species in the neritic ecosystem in the Southern Ocean, where it replaces the more oceanic Antarctic krill. It is essential to understand the variation of target strength （TS in dB re l m^2） with the different body size to accurately estimate ice krill stocks. However, there is comparatively little knowledge of the acoustic backscatter of ice krill. The TS of individual, formalin-preserved, tethered ice krill was measured in a freshwater test tank at 38, 120, and 200 kHz with a calibrated split-beam echo sounder system. Mean TS was obtained from 21 individual ice krill with a broad range of body lengths （L： 13-36 iron）. The length （L, mm） to wet weight （W; mg） relationship for ice krill was 11/=0.001 21g^103~L35s （R2=0.96）. The mean TS-to-length relationship were TS38kHz=-177.4＋57log10（L）, （R^2=0.86）; TS120kHz= -129.9＋31.561ogf0（L）, （R2=0.87）; and TS200kHz=-117.6＋24.661ogre（L）, （R2=0.84）. Empirical estimates of the relationship between the TS and body length of ice krill were established at 38, 120, and 200 kHz and compared with predictions obtained from both the linear regression model of Greene et al. （1991） and the Stochastic Distorted Wave Born Approximation （SDWBA） model. This result might be applied to improve acoustic detection and density estimation of ice krill in the Southern Ocean. Further comparative studies are needed with in situ target strength including various body lengths of ice krill.展开更多
Oxidative hair dyes containingρ-phenylenediamine(PPD)are reported to induce an allergic reaction by promoting oxidative stress when absorbed through the skin.Despite the associated risk,these hair dyes remain popular...Oxidative hair dyes containingρ-phenylenediamine(PPD)are reported to induce an allergic reaction by promoting oxidative stress when absorbed through the skin.Despite the associated risk,these hair dyes remain popular owing to their convenience and sharpness of color.This makes it important to minimize the cytotoxicity and oxidative stress induced by PPD-containing hair dyes.Ecklonia cava extract has been evaluated in different studies for its protective effects against external stress in fibroblasts and keratinocytes.Our study was aimed at using in-vitro and in-vivo models to investigate the extract’s effects on cytotoxicity of and oxidative stress induced by PPD-containing hair dyes.Analysis of CIEL*a*b*Color space was first used to determine the range of E.cava extract that would not interfere with the coloring ability of the dye upon addition.Subsequently,the set ranges of E.cava extract(5% and 7%)were added to the hair dye and their toxicity assessed by evaluating the viability of fibroblasts and keratinocytes.The effects on developmental phenotypes and induction of oxidative stress by hair dye were evaluated and compared with those of hair dyes containing different contents of E.cava extract using an in-vivo zebrafish model.Our results showed that E.cava extract in hair dye could significantly decrease the cytotoxicity and levels of oxidative stress caused by hair dyes containing PPD in both in-vitro and in-vivo models.These results suggest that the addition of 7% E.cava extract to 250μg/mL hair dye does not interfere with the coloring ability of the dye while showing significant protective eff ects against the hair dye.The study proposes that the use of E.cava extract as an adduct to hair dyes containing PPD reduces the cytotoxicity and oxidative stress induced by these hair dyes.展开更多
A down-scaled operational oceanographic system is developed for the coastal waters of Korea using a re- gional ocean modeling system （ROMS）. The operational oceanographic modeling system consists of at- mospheric an...A down-scaled operational oceanographic system is developed for the coastal waters of Korea using a re- gional ocean modeling system （ROMS）. The operational oceanographic modeling system consists of at- mospheric and hydrodynamic models. The hydrodynamic model, ROMS, is coupled with wave, sediment transport, and water quality modules. The system forecasts the predicted results twice a day on a 72 h basis, including sea surface elevation, currents, temperature, salinity, storm surge height, and wave information for the coastal waters of Korea. The predicted results are exported to the web-GIS-based coastal informa- tion system for real-time dissemination to the public and validation with real-time monitoring data using visualization technologies. The ROMS is two-way coupled with a simulating waves nearshore model, SWAN, for the hydrodynamics and waves, nested with the meteorological model, WRE for the atmospheric surface forcing, and externally nested with the eutrophication model, CE-QUAL-ICM, for the water quality. The op- erational model, ROMS, was calibrated with the tidal surface observed with a tide-gage and verified with current data observed by bottom-mounted ADCP or AWAC near the coastal waters of Korea. To validate the predicted results, we used real-time monitoring data derived from remote buoy system, HF-radar, and geostationary ocean color imager （GOCI）. This down-scaled operational coastal forecasting system will be used as a part of the Korea operational oceanographic system （KOOS） with other operational oceanographic systems.展开更多
Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island of Weno,Chuuk St...Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island of Weno,Chuuk State in Micronesia.The phenol content,antioxidant activity(based on DPPH-free radical scavenging)and tyrosinase inhibitory activity in different tissues(leaves,barks and roots)of Rhizophora stylosa(R.stylosa)and Sonneratia alba(S.alba),collected from the island of Weno.Results:Total phenol content ranged from 4.87 to 11.96 mg per g of freeze dried samples.The highest antioxidant activity was observed in R.styiosa bark(85.5%).The highest tyrosinase inhibitory activity was found in S.alba bark.Also,total phenol content and antioxidant activity were higher in methanol extracts than in aqueous extracts.Conclusions:Taken together,the results of this study proved that mangroves can be excellent sources of antioxidant compounds.展开更多
An analysis of the radar backscattering from the ocean surface covered by oil spill is presented using a mi- crowave scattering model and Monte-Carlo simulation. In the analysis, a one-dimensional rough sea sur- face ...An analysis of the radar backscattering from the ocean surface covered by oil spill is presented using a mi- crowave scattering model and Monte-Carlo simulation. In the analysis, a one-dimensional rough sea sur- face is numerically generated with an ocean waveheight spectrum for a given wind velocity. A two-layered medium is then generated by adding a thin oil layer on the simulated rough sea surface. The electric fields backscattered from the sea surface with two-layered medium are computed with the method of moments （MoM）, and the backscattering coefficients are statistically obtained with N independent samples for each oil-spilled surface using the Monte-Carlo technique for various conditions of surface roughness, oil-layer thickness, frequency, polarization and incidence angle. The numerical simulation results are compared with theoretical models for clean sea surfaces and SAR images of an off-spilled sea surface caused by the Hebei （Hebei province, China） Spirit oil tanker in 2007. Further, conditions for better oil spill extraction are sought by the numerical simulation on the effects of wind speed and oil-layer thickness at different inci- dence angles on the backscattering coefficients.展开更多
An integrally coupled wave-tide-surge model was developed and then applied to the simulation of the wave-typhoon surge for the typhoon Isewan （typhoon Vera （5915））, which is the strongest typhoon that has struck J...An integrally coupled wave-tide-surge model was developed and then applied to the simulation of the wave-typhoon surge for the typhoon Isewan （typhoon Vera （5915））, which is the strongest typhoon that has struck Japan and caused incalculable damage. An integrally coupled tide-surge-wave model using identical and homogeneous meshes in an unstructured grid system was used to correctly resolve the physics of wave-circulation interaction in both models. All model components were validated independently. The storm surge and wave properties such as the surge height, the significant wave height, wave period and direction were reproduced reasonably under the meteorological forcing, which was reprocessed to be close to the observations. The resulting modeling system can be used extensively for the prediction of the storm surge and waves and the usual barotropic forecast.展开更多
Objective:To establish a novel and highly specific loop-mediated isothermal amplification(LAMP) assay for the identification of nervous necrosis virus(NNV) infection.Methods:A set of synthesized primers was used to ma...Objective:To establish a novel and highly specific loop-mediated isothermal amplification(LAMP) assay for the identification of nervous necrosis virus(NNV) infection.Methods:A set of synthesized primers was used to match the sequences of a specific region of the nnr gene from the National Center for Biotechnology Information database,not originating from NNV-infected fish,the efficiency and specificity of LAMP were measured dependent on the concentration of DNA polymerase and the reaction temperature and time.In addition,to determine species-specific LAMP primers,cross reactivity testing was applied to the reaction between NVV and other virus families including viral hemorrhagic septicemia virus and marine birnavirus.Results:The optimized LAMP reaction carried out at 64 ℃ for 60 min,and above 4 U Bst DNA polymerase.The sensitivity of LAMP for the detection of nnv was thus about 10 times greater than the sensitivity of polymerase chain reaction.The LAMP assay primers were specific for the detection NNV infection in Epinephelus septemfasciatus.Conclusions:The development of LAMP primers based on genetic information from a public database,not virus-infected samples,may provide a very simple and convenient method to identify viral infection in aquatic organisms.展开更多
Harmful algal blooms (HABs), caused by the overgrowth of certain phytoplankton species, have negative effects on marine environments and coastal fisheries. In addition to cell-counting methods using phytoplankton nets...Harmful algal blooms (HABs), caused by the overgrowth of certain phytoplankton species, have negative effects on marine environments and coastal fisheries. In addition to cell-counting methods using phytoplankton nets, a hydroacoustic technique based on acoustic backscattering has been proposed for the detection of phytoplankton blooms. However, little is known of the acoustic properties of HAB species. In this study, as essential data to support this technique, we measured the acoustic properties of two HAB species, Akashiwo sanguinea and Alexandrium affine, which occur in the South Sea off the coast of Korea. Due to the small size of the target, we used ultrasound for the measurements. Experiments were conducted under laboratory and field conditions. In the laboratory experiment, the acoustic signal received from each species was directly proportional to the cell abundance. We derived a relationship between the cell abundance and acoustic signal received for each species. The measured signals were compared to predictions of a fluid sphere scattering model. When A. sanguinea blooms appeared at an abundance greater than 3 500 cells/mL, the acoustic signals varied with cell abundance, showing a good correlation. These results confirm that acoustic measurements can be used to detect HAB species.展开更多
基金This research was a part of the projects titled"Development of Korea Operational Oceanographic System(KOOS),Phase2","Development of Environmental Information System for NSR Navigation","Base Research for Building Wide Integrated Surveillance System of Marine Territory",and"Construction of Ocean Research Stations and their Application Studies"funded by the Ministry of Oceans and Fisheries,Korea
文摘In the present article, we introduce a high resolution sea surface temperature （SST） product generated daily by Korea Institute of Ocean Science and Technology （KIOST）. The SST product is comprised of four sets of data including eight-hour and daily average SST data of I km resolution, and is based on the four infrared （IR） satellite SST data acquired by advanced very high resolution radiometer （AVHRR）, Moderate Resolution Imaging Spectroradiometer （MODIS）, Multifunctional Transport Satellites-2 （MTSAT-2） Imager and Meteorological Imager （MI）, two microwave radiometer SSTs acquired by Advanced Microwave Scanning Radiometer 2 （AMSR2）, and WindSAT with in-situ temperature data. These input satellite and in-situ SST data are merged by using the optimal interpolation （OI） algorithm. The root-mean-square-errors （RMSEs） of satellite and in-situ data are used as a weighting value in the OI algorithm. As a pilot product, four SST data sets were generated daily from Ianuary to December 2013. In the comparison between the SSTs measured by moored buoys and the daily mean KIOST SSTs, the estimated RMSE was 0.71~C and the bias value was -0.08~C. The largest RMSE and bias were 0.86 and -0.26~C respectively, observed at a buoy site in the boundary region of warm and cold waters with increased physical variability in the Sea of Iapan/East Sea. Other site near the coasts shows a lower RMSE value of 0.60~C than those at the open waters. To investigate the spatial distributions of SST, the Group for High Resolution Sea Surface Temperature （GHRSST） product was used in the comparison of temperature gradients, and it was shown that the KIOST SST product represents well the water mass structures around the Korean Peninsula. The KIOST SST product generated from both satellite and buoy data is expected to make substantial contribution to the Korea Operational Oceanographic System （KOOS） as an input parameter for data assimilation.
基金The China-Korea Cooperation Project on the Development of Oceanic Monitoring and Prediction System on Nuclear Safetythe Youth Foundation of the First Institute of Oceanography(FIO),State Oceanic Administration of China,under contract Nos GY0215P01 and GY2015P03+3 种基金the Project of the National Programme on Global Change and Air-sea Interaction under contract No.GASI-03-IPOVAI-05the NSFC-Shandong Joint Fund of Marine Science Research Centers of China under contract No.U1406404the National Natural Science Foundation of China Project under contract No.41506035the KIOST Project under contract No.PE99304
文摘The Fukushima nuclear accident in 2011 released large amounts of radionuclides, including ^（137）Cs, into the Pacific Ocean. A quasi-global ocean radioactive transport model with horizontal grid spacing of 0.5°×0.5° and 21 vertical layers was thereafter established to study the long-term transport of the Fukushima-derived ^（137）Cs in the ocean.The simulation shows that the plume of ^（137）Cs would be rapidly transported eastward alongside the Kuroshio Current and its extensions. Contaminated waters with concentrations lower than 2 Bq/m3 would reach the west coast of North America 4 or 5 years after the accident. The ^（137）Cs tends to be carried, despite its very low concentration, into the Indian and South Pacific Oceans by 2016 via various branches of ocean currents.Meanwhile, the ^（137）Cs concentrations in the western part of the North Pacific Ocean decrease rapidly with time. Up to now the highly contaminated waters have remained in the upper 400 m, showing no evidence of significant penetration to deeper layers.
基金The Project"Development of Korea Operational Oceanographic System(PM57041)"funded by the Ministry of Land,Transport and Maritime Affairs of the Korean Governmentthe Project"Cooperation on the Development of Basic Technologies for the Yellow Sea and East China Sea Operational Oceanographic System(YOOS)"funded by the China-Korea Joint Ocean Research Center(CKJORC)
文摘A standard skill assessment （SA） tool was developed and implemented to evaluate the performance of op- erational forecast models in the Korea operational oceanographic system. The SA tool provided a robust way to assess model skill in the system by comparing predictions and observations, and involved the com- putation of multiple skill metrics including correlation and error skills. User- and system-based acceptance criteria of skill metrics were applied to determine whether predictions were acceptable for the system. To achieve this, the tool produced a time series comparison plot, a skill score table, and an advanced sum- marized diagram to effectively demonstrate the multiple skill scores. Moreover, the SA was conducted to evaluate both atmospheric and hydrodynamic forecast variables. For the atmospheric variables, acceptable error criteria were preferable to acceptable correlation criteria over short timescales, since the mean square error overwhelmed the observation variance. Conversely, for the hydrodynamic variables, acceptable root mean square percentage error （e.g., perms） criteria were preferable to acceptable error （e.g., erms） criteria owing to the spatially variable tidal intensity around the Korean Peninsula. Furthermore, the SA indicated that predetermined acceptance error criteria were appropriate to satisfy a target central frequency （fc） for which errors fell within the specified limits （i.e., the .fc equals 70%）.
基金Supported by the Korea Polar Research Institute(Nos.PE14150,PM15040)
文摘A bstract The venerid clam(M actra veneriformis Reeve 1854) is one of the main cultured bivalve species in intertidal and shallow subtidal ecosystems along the west coast of Korea. To understand the effects of ocean acidifi cation on the early life stages of Korean clams, we investigated shell growth and abnormality rates and types in the D-shaped, umbonate veliger, and pediveliger stages of the venerid clam M. veneriformis during exposure to elevated seawater pCO_2. In particular, we examined abnormal types of larval shell morphology categorized as shell deformations, shell distortions, and shell fi ssures. Specimens were incubated in seawater equilibrated with bubbled CO_2-enriched air at(400±25)×10^(-6)(ambient control),(800±25)×10^(-6)(high pCO_2), or(1 200±28)×10^(-6)(extremely high pCO_2), the atmospheric CO_2 concentrations predicted for the years 2014, 2084, and 2154(70-year intervals; two human generations), respectively, in the Representative Concentration Pathway(RCP) 8.5 scenario. The mean shell lengths of larvae were signifi cantly decreased in the high and extremely high pCO_2 groups compared with the ambient control groups. Furthermore, under high and extremely high pCO_2 conditions, the cultures exhibited signifi cantly increased abundances of abnormal larvae and increased severity of abnormalities compared with the ambient control. In the umbonate veliger stage of the experimental larvae, the most common abnormalities were shell deformations, distortions, and fi ssures; on the other hand, convex hinges and mantle protuberances were absent. These results suggest that elevated CO_2 exerts an additional burden on the health of M. veneriformis larvae by impairing early development.
基金This research was supported by a project on the sustainable research and development of Dokdo(Grant No.PG52911)which is funded by the Ministry of Oceans and Fisheries,South Korea.
文摘Quaternary intraplate magmatism formed several volcanic islands and seamounts,including Dokdo(DD),Ulleungdo(UD),Simheungtack(ST),Anyongbok,and Isabu in the southwest of the East Sea back-arc basin.In this study,we present whole-rock geochemical,zircon U–Pb age,and in situ O–Hf isotope data for the submerged volcanic rocks from DD,UD,and ST to provide new insights into the eruption timing of these volcanoes and constrain the magma evolution processes.All samples used in this study were trachytes and exhibited ferroan,alkalic,and metaluminous to weakly peraluminous characteristics.They showed light rare earth element(REE)-enriched patterns with(La/Yb)N ratios of 25.3–31.7 and mostly negative Eu anomalies in a chondrite-normalized REE plot.In addition,they were enriched in large-ion lithophile elements and high field strength elements;they exhibited positive Pb anomalies and strongly negative Ba,Sr,P,and Ti anomalies.The zircons yielded a weighted-mean 206Pb/238U age of 2.61,0.348–0.704,and 2.76–2.94 Ma for the DD,UD,and ST trachytes,respectively.All zircons exhibited lowerδ^(18)O values than normal depleted mantle values,regardless of the crystallization age and spatial distribution of volcanoes.Theδ^(18)O values showed no correlation with U contents or Th/U ratios,indicating that the lowδ^(18)O signatures were of primary magmatic origin.The Hf isotopic compositions of the zircons were relatively heterogeneous but predominately characterized by positive eHf values.Binary O–Hf mixing modeling revealed that low-δ^(18)O rocks with positive eHf values from the UD and ST volcanoes were derived from a hybrid source of recycled juvenile crustal materials with low-δ^(18)O and positive eHf signatures and an enriched mantle source with normalδ^(18)O and negative eHf values.The juvenile oceanic crust in the source was likely metasomatized by seawater at high temperatures prior to melting.In contrast,the felsic magma that formed the DD volcanoes may have assimilated with regional basement rocks(Triassic–Jurassic granitoids),resulting in increasedδ^(18)O values and decreased eHf values relative to those of the UD and ST volcanoes.Our study highlights the significant contribution of recycled oceanic crust materials to the generation of the Quaternary magmas.
基金supported by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)and Ministry of Trade,Industry&Energy(MOTIE)of the Republic of Korea(No.20212010200020)This study was also supported by Korea CCUS Association(K-CCUS)grant funded by the Korea Government(MOE,MOTIE)(KCCUS20220001,Human Resources Program for Reduction of Greenhouse Gases).
文摘This study presents the concentration of radon-222(Rn)in bottom seawater and seawater 10 m above the seabed in the central Yellow Sea,where CO_(2) geological storage is considered.Five sampling points were selected,considering the locations of the buried faults possibly acting as migration pathways of injected CO_(2).The Rn concentrations of bottom seawater range from 0 to 26±10 Bq m-3,whereas those of seawater 10 m above the seabed range from 0 to 16±6 Bq m-3.The variation of Rn diffusion from the seabed accounts for different Rn concentrations at each sampling point.Based on CTD and sediment core data,it was found that the study area was characterized by summer stratification,muddy surface sediment,and homogeneous sediment resuspension profile above the seabed.These observations suggest that the Rn diffusion from the seabed varied insignificantly in the study area.Relatively high Rn concentrations were found in sampling points near the buried faults,implying that the location of the buried faults is critical as monitoring target.Although limited by the lack of sampling points,this study provides baseline Rn concentrations,which will help to implement a CO_(2) monitoring program in the central Yellow Sea.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.RS-2024-00334159)the Korea Institute of Ocean Science and Technology(KIOST)project entitled“Development of Maritime Domain Awareness Technology for Sea Power Enhancement”(PEA0332).
文摘Side-scan sonar(SSS)is essential for acquiring high-resolution seafloor images over large areas,facilitat-ing the identification of subsea objects.However,military security restrictions and the scarcity of subsea targets limit the availability of SSS data,posing challenges for Automatic Target Recognition(ATR)research.This paper presents an approach that uses Cycle-Consistent Generative Adversarial Networks(CycleGAN)to augment SSS images of key subsea objects,such as shipwrecks,aircraft,and drowning victims.The process begins by constructing 3D models to generate rendered images with realistic shadows frommultiple angles.To enhance image quality,a shadowextractor and shadow region loss function are introduced to ensure consistent shadowrepresentation.Additionally,amulti-resolution learning structure enables effective training,even with limited data availability.The experimental results show that the generated data improved object detection accuracy when they were used for training and demonstrated the ability to generate clear shadow and background regions with stability.
基金supported by the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(NO.SML2021SP201)the National Natural Science Foundation of China(Grant No.42306200 and 42306216)+2 种基金the National Key Research and Development Program of China(Grant No.2023YFC3008100)the Innovation Group Project of the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(Grant No.311021004)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(Project No.SL2021ZD203)。
文摘Tropical cyclones(TCs)are complex and powerful weather systems,and accurately forecasting their path,structure,and intensity remains a critical focus and challenge in meteorological research.In this paper,we propose an Attention Spatio-Temporal predictive Generative Adversarial Network(AST-GAN)model for predicting the temporal and spatial distribution of TCs.The model forecasts the spatial distribution of TC wind speeds for the next 15 hours at 3-hour intervals,emphasizing the cyclone's center,high wind-speed areas,and its asymmetric structure.To effectively capture spatiotemporal feature transfer at different time steps,we employ a channel attention mechanism for feature selection,enhancing model performance and reducing parameter redundancy.We utilized High-Resolution Weather Research and Forecasting(HWRF)data to train our model,allowing it to assimilate a wide range of TC motion patterns.The model is versatile and can be applied to various complex scenarios,such as multiple TCs moving simultaneously or TCs approaching landfall.Our proposed model demonstrates superior forecasting performance,achieving a root-mean-square error(RMSE)of 0.71 m s^(-1)for overall wind speed and 2.74 m s^(-1)for maximum wind speed when benchmarked against ground truth data from HWRF.Furthermore,the model underwent optimization and independent testing using ERA5reanalysis data,showcasing its stability and scalability.After fine-tuning on the ERA5 dataset,the model achieved an RMSE of 1.33 m s^(-1)for wind speed and 1.75 m s^(-1)for maximum wind speed.The AST-GAN model outperforms other state-of-the-art models in RMSE on both the HWRF and ERA5 datasets,maintaining its superior performance and demonstrating its effectiveness for spatiotemporal prediction of TCs.
基金The China-Korea cooperative project on the Yellow Sea Cold Water Mass under contract No.PE99165,funded by the Korea Institute of Ocean Science and Technology
文摘The Yellow Sea Cold Water Mass （YSCWM） is one of the important water mass in the Yellow Sea （YS）. It is distributed in the lower layer in the Yellow Sea central trough with the temperature less than 10℃ and the salinity lower than 33.0. To understand the variability of the YSCWM, the hydrographic data obtained in April and August during 2009-2011 are analyzed in the southeastern Yellow Sea. In August 2011, relatively warm and saline water compared with that in 2009 and 2010 was detected in the lower layer in the Yellow Sea central area. Although the typhoon passed before the cruise, the salinity in the Yellow Sea central trough is much higher than the previous season. It means that the saline event cannot be explained by the typhoon but only by the intrusion of saline water during the previous winter. In April 2011, actually, warm and saline water （T 〉 10~C, S 〉34） was observed in the deepest water depth of the southeastern area of the Yellow Sea. The wind data show that the northerly wind in 2011 winter is stronger than in 2009 and 2010 winter season. The strong northerly wind can trigger the intrusion of warm and saline Yellow Sea Warm Current. Therefore, it is proposed that the strong northerly wind in winter season leads to the intrusion of the Yellow Sea Warm Current into the Yellow Sea central trough and influenced a variability of the YSCWM in summer.
基金Part of the Korea-China Cooperative Project on the Yellow Sea Cold Water Massa grant from the Korea Ocean Research and Development Institute(PE99165)the samples were partly supplied from NFRDI(RP-2012-ME-051)
文摘To investigate the distribution, abundance, and species composition of dinoflagellate cysts in the Yellow Sea, surface sediment samples were collected at 37 sites, including the Korean dump site. Twenty-one di- noflagellate cyst taxa were identified, with the assemblages dominated mainly by Spiniferites bulloideus, Operculodinium centrocarpum, and cyst of Alexandrium catenella/tarnarense type. A high frequency of O. centrocarpum in the Yellow Sea was observed for the first time, and it is likely that this can be attributed to the dynamics of the Yellow Sea Cold Water Mass and the Changjiang （Yangtze） River runoff. Total cyst concentrations ranged from 23 to 48 442 cysts/g dry weight, and high cyst concentrations were recorded adjacent to the dumping site. This result suggests that anthropogenic activities such as ocean dumping s- timulate the growth of dinoflagellates in the Yellow Sea, which in turn leads to high levels of dinoflagellate cyst production.
基金supported by the Public Welfare&Safety Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science,ICT&Future Planning(PN65760)
文摘Objecive:To screen the fatty acid(FA) composition of 20 marine microalgae species,including seven Diophyceae,six Bacillariophyeae four Chlorophyceae,two Haptophyceae and one Raphidophyceae species.Methods:Microalgal cells cultured at the Korea Institute of Ocean Science & Technology were harvested during the late exponential growth phase and the FA composition analyzed.Results:The FA composition of microalgae was speciesspecific.For example,seven different species of Dinophyceae were composed primarily of C14:0,C16:0.C18:0.C20:4n-6.C20:5n-3 and C22:6n-3.while C14:0.C16:0,C16:1.C18:0.C20:5n-3 and C22:6n-3 were abundant FAs in six species of Bacillariophyceae.In addition,four Chlurophyceae,two Haptopkyeeae and one Raphidophyceae species all contained a high degree of C16:1 n-7[(9.2R-34.91)%and(34.48-35.04)%].C14:0[(13.34-25.96)%]and[(26.69-Z8.24)%],and C16:0[(5.89-29.15)%]and[(5.70-16.81)%].Several factors contribute to the nutritional value of microalgae.including the polyunsaturated FA content and n-3 to n-6 FA ratio,which could be used to assess the nutritional quality of microalgae.Conclusions:This study is the first comprehensive assessment of the FA composition and nutritional value of microalgae species in South Korea,and identifies the potential utility of FAs as species-specific biomarkers.
基金supported by the Public Welfare & Safety Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science,ICT & Future Planning (NRF-2013M3A2A1067529)
文摘Objective: To determine skin whitening and wrinkle improvement efficacy, glycoprotein fractions were extracted from liquid extracts of boiled sea cucumber and their effects on tyrosine and elastase inhibitory activities were assayed. Methods: Fractions above and below 50 k Da(>50 kD a and <50 kD a) were extracted via a series of steps invovling: boiling, filtering, desalting and freeze drying. Cytotoxicity, skin whitening and wrinkle-removing effects of boiled liquid were determined. Results: Our MTT data showed that neither glycoprotein fraction of boiled liquid induces cellular cytotoxicity up to a concentration of 10 mg/m L treatment of the mouse melanoma cell line, B16F10, with 10 mg/m L >50 kDa enhanced tyrosinase and elastase inhibitory activities by 50.84% and 28.78%, respectively. Correlations of the >50 kD a concentration with tyrosinase inhibitory(R^2=0.968) and elastase inhibitory(R2=0.983) efficacy were significant. Conclusions: >50 kD a glycoprotein fraction isolated from liquid extracts of boiled sea cucumber, which can serve as a functional cosmetic ingredient for whitening and wrinkle improvement of skin.
基金Supported by the Korea Polar Research Institute(No.PP14020)the Korea Institute of Ocean Science and Technology(No.PN65250)
文摘Ice krill is the keystone species in the neritic ecosystem in the Southern Ocean, where it replaces the more oceanic Antarctic krill. It is essential to understand the variation of target strength （TS in dB re l m^2） with the different body size to accurately estimate ice krill stocks. However, there is comparatively little knowledge of the acoustic backscatter of ice krill. The TS of individual, formalin-preserved, tethered ice krill was measured in a freshwater test tank at 38, 120, and 200 kHz with a calibrated split-beam echo sounder system. Mean TS was obtained from 21 individual ice krill with a broad range of body lengths （L： 13-36 iron）. The length （L, mm） to wet weight （W; mg） relationship for ice krill was 11/=0.001 21g^103~L35s （R2=0.96）. The mean TS-to-length relationship were TS38kHz=-177.4＋57log10（L）, （R^2=0.86）; TS120kHz= -129.9＋31.561ogf0（L）, （R2=0.87）; and TS200kHz=-117.6＋24.661ogre（L）, （R2=0.84）. Empirical estimates of the relationship between the TS and body length of ice krill were established at 38, 120, and 200 kHz and compared with predictions obtained from both the linear regression model of Greene et al. （1991） and the Stochastic Distorted Wave Born Approximation （SDWBA） model. This result might be applied to improve acoustic detection and density estimation of ice krill in the Southern Ocean. Further comparative studies are needed with in situ target strength including various body lengths of ice krill.
文摘Oxidative hair dyes containingρ-phenylenediamine(PPD)are reported to induce an allergic reaction by promoting oxidative stress when absorbed through the skin.Despite the associated risk,these hair dyes remain popular owing to their convenience and sharpness of color.This makes it important to minimize the cytotoxicity and oxidative stress induced by PPD-containing hair dyes.Ecklonia cava extract has been evaluated in different studies for its protective effects against external stress in fibroblasts and keratinocytes.Our study was aimed at using in-vitro and in-vivo models to investigate the extract’s effects on cytotoxicity of and oxidative stress induced by PPD-containing hair dyes.Analysis of CIEL*a*b*Color space was first used to determine the range of E.cava extract that would not interfere with the coloring ability of the dye upon addition.Subsequently,the set ranges of E.cava extract(5% and 7%)were added to the hair dye and their toxicity assessed by evaluating the viability of fibroblasts and keratinocytes.The effects on developmental phenotypes and induction of oxidative stress by hair dye were evaluated and compared with those of hair dyes containing different contents of E.cava extract using an in-vivo zebrafish model.Our results showed that E.cava extract in hair dye could significantly decrease the cytotoxicity and levels of oxidative stress caused by hair dyes containing PPD in both in-vitro and in-vivo models.These results suggest that the addition of 7% E.cava extract to 250μg/mL hair dye does not interfere with the coloring ability of the dye while showing significant protective eff ects against the hair dye.The study proposes that the use of E.cava extract as an adduct to hair dyes containing PPD reduces the cytotoxicity and oxidative stress induced by these hair dyes.
基金The project entitled Cooperation on the Development of Basic Technologies for the Yellow Sea and East China Sea Operational Oceanographic System funded by the China-Korea Joint Ocean Research Centerthe project entitled"Development of Korea Operational Oceanographic System"funded by the Ministry of Oceans and Fisheries,Koreathe project Functional Improvement of Korea Ocean Satellite Center and Development of the Marine Environment Impact Prediction Program funded by the Korea Institute of Ocean Science and Technology
文摘A down-scaled operational oceanographic system is developed for the coastal waters of Korea using a re- gional ocean modeling system （ROMS）. The operational oceanographic modeling system consists of at- mospheric and hydrodynamic models. The hydrodynamic model, ROMS, is coupled with wave, sediment transport, and water quality modules. The system forecasts the predicted results twice a day on a 72 h basis, including sea surface elevation, currents, temperature, salinity, storm surge height, and wave information for the coastal waters of Korea. The predicted results are exported to the web-GIS-based coastal informa- tion system for real-time dissemination to the public and validation with real-time monitoring data using visualization technologies. The ROMS is two-way coupled with a simulating waves nearshore model, SWAN, for the hydrodynamics and waves, nested with the meteorological model, WRE for the atmospheric surface forcing, and externally nested with the eutrophication model, CE-QUAL-ICM, for the water quality. The op- erational model, ROMS, was calibrated with the tidal surface observed with a tide-gage and verified with current data observed by bottom-mounted ADCP or AWAC near the coastal waters of Korea. To validate the predicted results, we used real-time monitoring data derived from remote buoy system, HF-radar, and geostationary ocean color imager （GOCI）. This down-scaled operational coastal forecasting system will be used as a part of the Korea operational oceanographic system （KOOS） with other operational oceanographic systems.
基金supported by Korea Institute of Ocean Science&Technology research project:E99161
文摘Objective:To find out and compare the in vitro antioxidant and tyrosinase inhibitory activities of two species of mangrove plants.Methods:Mangrove samples were harvested at the shoreline on the island of Weno,Chuuk State in Micronesia.The phenol content,antioxidant activity(based on DPPH-free radical scavenging)and tyrosinase inhibitory activity in different tissues(leaves,barks and roots)of Rhizophora stylosa(R.stylosa)and Sonneratia alba(S.alba),collected from the island of Weno.Results:Total phenol content ranged from 4.87 to 11.96 mg per g of freeze dried samples.The highest antioxidant activity was observed in R.styiosa bark(85.5%).The highest tyrosinase inhibitory activity was found in S.alba bark.Also,total phenol content and antioxidant activity were higher in methanol extracts than in aqueous extracts.Conclusions:Taken together,the results of this study proved that mangroves can be excellent sources of antioxidant compounds.
基金The Project "Development of Korea Operational Oceanographic System (PM57041)" funded by the Ministry of Land, Transport and Maritime Affairs of Korean Governmentthe Project "Cooperation on the Development of Basic Technologies for the Yellow Sea and East China Sea Operational Oceanographic System (YOOS)" funded by CKJORC and the Basic Research Projects (PE98731, PG47770 and PE98732) of the Korea Institute Ocean Science and Technologysupport by the PASCO Corporation,Japan is also apreciated
文摘An analysis of the radar backscattering from the ocean surface covered by oil spill is presented using a mi- crowave scattering model and Monte-Carlo simulation. In the analysis, a one-dimensional rough sea sur- face is numerically generated with an ocean waveheight spectrum for a given wind velocity. A two-layered medium is then generated by adding a thin oil layer on the simulated rough sea surface. The electric fields backscattered from the sea surface with two-layered medium are computed with the method of moments （MoM）, and the backscattering coefficients are statistically obtained with N independent samples for each oil-spilled surface using the Monte-Carlo technique for various conditions of surface roughness, oil-layer thickness, frequency, polarization and incidence angle. The numerical simulation results are compared with theoretical models for clean sea surfaces and SAR images of an off-spilled sea surface caused by the Hebei （Hebei province, China） Spirit oil tanker in 2007. Further, conditions for better oil spill extraction are sought by the numerical simulation on the effects of wind speed and oil-layer thickness at different inci- dence angles on the backscattering coefficients.
基金supported by the China-Korea Cooperative Research Project funded by CKJORCa major project titled the development of the marine environmental impact prediction system funded by KIOSTsupported by the project of KISTI for the development of HPC-based management system against national-scale disaster
文摘An integrally coupled wave-tide-surge model was developed and then applied to the simulation of the wave-typhoon surge for the typhoon Isewan （typhoon Vera （5915））, which is the strongest typhoon that has struck Japan and caused incalculable damage. An integrally coupled tide-surge-wave model using identical and homogeneous meshes in an unstructured grid system was used to correctly resolve the physics of wave-circulation interaction in both models. All model components were validated independently. The storm surge and wave properties such as the surge height, the significant wave height, wave period and direction were reproduced reasonably under the meteorological forcing, which was reprocessed to be close to the observations. The resulting modeling system can be used extensively for the prediction of the storm surge and waves and the usual barotropic forecast.
基金supported by the Korea Institute of Ocean Science&Technology(No.PE99315)
文摘Objective:To establish a novel and highly specific loop-mediated isothermal amplification(LAMP) assay for the identification of nervous necrosis virus(NNV) infection.Methods:A set of synthesized primers was used to match the sequences of a specific region of the nnr gene from the National Center for Biotechnology Information database,not originating from NNV-infected fish,the efficiency and specificity of LAMP were measured dependent on the concentration of DNA polymerase and the reaction temperature and time.In addition,to determine species-specific LAMP primers,cross reactivity testing was applied to the reaction between NVV and other virus families including viral hemorrhagic septicemia virus and marine birnavirus.Results:The optimized LAMP reaction carried out at 64 ℃ for 60 min,and above 4 U Bst DNA polymerase.The sensitivity of LAMP for the detection of nnv was thus about 10 times greater than the sensitivity of polymerase chain reaction.The LAMP assay primers were specific for the detection NNV infection in Epinephelus septemfasciatus.Conclusions:The development of LAMP primers based on genetic information from a public database,not virus-infected samples,may provide a very simple and convenient method to identify viral infection in aquatic organisms.
基金project titled "Establishment and demonstration of red tide detection and prediction system for minimizing red tide damage" funded by the Ministry of Oceans and Fisheries, Korea (PM61410)
文摘Harmful algal blooms (HABs), caused by the overgrowth of certain phytoplankton species, have negative effects on marine environments and coastal fisheries. In addition to cell-counting methods using phytoplankton nets, a hydroacoustic technique based on acoustic backscattering has been proposed for the detection of phytoplankton blooms. However, little is known of the acoustic properties of HAB species. In this study, as essential data to support this technique, we measured the acoustic properties of two HAB species, Akashiwo sanguinea and Alexandrium affine, which occur in the South Sea off the coast of Korea. Due to the small size of the target, we used ultrasound for the measurements. Experiments were conducted under laboratory and field conditions. In the laboratory experiment, the acoustic signal received from each species was directly proportional to the cell abundance. We derived a relationship between the cell abundance and acoustic signal received for each species. The measured signals were compared to predictions of a fluid sphere scattering model. When A. sanguinea blooms appeared at an abundance greater than 3 500 cells/mL, the acoustic signals varied with cell abundance, showing a good correlation. These results confirm that acoustic measurements can be used to detect HAB species.
