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동아시아 주변해 정선 해양 관측망의 자료동화 영향 평가
No full text1960년대부터 한반도 주변 해역에서 국립수산과학원/한국해양자료센터(National Institute of Fisheries Science/Korea Oceanographic Data Center, NIFS/KODC)가 운영해 온 정선 해양 관측 시스템의 중요성에도 불구하고, 이러한 관측 자료가 해양 분야에 기여하는 바를 다룬 연구는 매우 부족하다. 본 연구에서는 이 정선 관측 시스템의 자료동화 효과를 규명하기 위해, 지구물리유체역학연구소(Geophysical Fluid Dynamics Laboratory, GFDL)에서 개발한 앙상블 결합 자료동화(Ensemble Coupled Data Assimilation, ECDA) 시스템을 활용하여 관측망 가상 실험(Observation System Simulation Experiment, OSSE)을 수행하였다. OSSE는 22개 정선 관측 라인에 적용되었으며, 동화 주기는 실제 정선 관측 주기와 유사한 2개월 주기로 설정하였다. 자료동화 효과를 극대화하기 위해 1개월 및 10일 주기의 실험도 추가로 수행하였다. 표층에서는 동해 북부의 warm bias 증가로 인해 10일 및 1개월 주기 실험의 동화 성능이 저하된 반면, 2개월 주기 실험은 상대적으로 양호한 성능을 보였다. 그러나 심층에서는 동해 북부에서 발생한 하강류의 영향으로 10일 및 1개월 주기의 동화가 단기 모의에서 더 나은
성능을 보였다. 이러한 결과는 자료동화 과정을 해석하는 물리적 메커니즘은 다르지만, 역편향 실험(Reverse bias experiment)에서도 유사한 동화 효과를 확인하였다. 본 연구는 장기해양 예측에 중요한 시사점을 제공할 것으로 기대된다.2
BLACK BOX FOR SUBMARINES
No full text본 발명은 유인 잠수정의 수중위치, 속도, 음성, 시간, 날짜 등을 기록하는 블랙박스에 관한 것으로, 유인 잠수정의 사고 발생시 자동 또는 수동으로 사출되어 수면으로 부상하도록 된 것으로, 전원이 공급되는 상태에서 co2 과다 감지시 또는 전원 차단시 탑승자 사망 사고로 간주하여 사출되도록 할 수 있고, 전원이 공급되지 않을 때에는 탑승자 사망으로 바로 간주하여 사출하도록 구성된 것임
Spectrogram-Based Acoustic Fault Diagnosis of Underwater Thrusters Using a Spectral-Aware Denoising Convolutional Neural Network and Vision Transformer
No full textUnderwater thruster failures pose a critical risk to the mission reliability of unmanned surface vehicles (USVs), especially during long-term autonomous operations. Conventional fault diagnosis approaches often rely on vibration sensors or controlled laboratory settings, which limits their practicality in dynamic marine environments. To overcome these challenges, a noncontact acoustic fault diagnosis framework that leverages microphone-based sensing combined with deep-learning techniques is presented in this paper. Acoustic signals acquired from underwater thrusters are converted into time frequency spectrograms using short time Fourier transform (STFT), and background noise is suppressed through a spectral-aware denoising convolutional neural network (SA-DnCNN). The denoised spectrograms are then used to train a vision Transformer (ViT-B/16) for the classification of four representative thruster conditions: normal, breakage, entanglement, and biofouling. The proposed SA-DnCNN + ViT model was validated using acoustic data obtained both in a controlled water tank environment and during real-world sea trials. Classification accuracies of 99.27% and 96.69% were achieved. Comparative experiments with CNN, ResNet50, and other denoising-based models confirmed the superiority of the proposed method in terms of robustness and precision. Notably, this study is one of the first experimental demonstrations of microphone-based diagnosis of thruster faults under actual marine conditions and highlights the potential of the method as a scalable and practical solution for real-time health monitoring of USVs. Future work will focus on expanding the acoustic dataset through long-term marine deployments and incorporating multimodal sensor fusion to improve diagnostic generalization and resilience across diverse maritime environments and operational scenarios.11Ysciescopu
Conservative behavior of dissolved black carbon in the northwestern Pacific marginal seas
No full textDissolved black carbon (DBC) represents the largest molecularly identifiable slow-cycling organic carbon pool in the ocean. However, its behavior remains debated due to large differences between its radiocarbon ages and residence times based on mass balance estimations, suggesting considerable removal in the source regions. Here, we show that DBC is predominantly derived from riverine sources and behaves conservatively throughout the entire water masses of the northwestern Pacific marginal seas—including the East China Sea, the Yellow Sea, and the East Sea (Japan Sea)—which are characterized by extreme biogeochemical alterations and long water residence times (~100 years). This conservative behavior is evidenced by a strong negative correlation between DBC and salinity, consistent mass balance estimates, and a uniform B6CA/B5CA marker ratio. Thus, we suggest that the discrepancy between DBC ages and residence times in the ocean is more likely due to substantially enhanced contemporary DBC production rather than removal pathways.11Ysciescopu
Nitrogen-Containing Sesquiterpenoids from the Sponge Stellitethya ingens as TRPA1 Antagonists
No full textBiological screening of marine sponge extracts against transient receptor potential ankyrin 1 (TRPA1) identified Stellitethya ingens as a promising source of secondary metabolites with potential antagonistic activity. A comprehensive investigation yielded 13 nitrogen-containing sesquiterpenoids (1-13) and eight glycerophosphocholines (16-23), including four previously undescribed bisabolene-type analogues (3 and 6-8) and one new phosphatidylcholine derivative (23). Structures were elucidated by extensive NMR and HR-ESIMS/MS analyses. The absolute configuration of 6 was determined via asymmetric synthesis, while that of 7 was assigned from NOE correlations and pyridine-induced deshielding effects. Isolated compounds were evaluated for TRPA1 antagonistic activity using a FLIPR-based calcium mobilization assay, and compounds 1, 3, and 12 exhibited moderate inhibitory effects without cytotoxicity against HEK cells. This study represents the first report of secondary metabolites from the genus Stellitethya and highlights bisabolene- and pupukeanane-type scaffolds as novel frameworks for TRPA1 antagonists, thereby expanding the chemical diversity of the underexplored order Tethyida and offering new chemotypes with potential relevance to analgesic drug discovery.11Nsciescopu
A Method for Detecting Maritime Traffic Anomalies Using Control Data and A Computer-readable Recording Medium On Which A Program For Performing The Method Is Recorded
No full text본 발명은 관제 데이터를 이용한 해상 교통 이상 탐지 방법 및 이를
수행하는 프로그램이 기록된 컴퓨터 판독이 가능한 기록매체에 관한 것으로,
보다 구체적으로 지상관제소, 선박, 항공 및 인공위성 중 적어도 하나로부터
관제 데이터가 획득되는 관제 데이터 획득단계, 상기 관제 데이터가 전처리되
는 데이터 전처리 단계, 전처리된 상기 관제 데이터로부터 관심영역이 선정되
고, 상기 관심영역에서 선박 운항 시 발생되는 정보인 선박운항정보가 획득되
는 선박운항정보 획득단계 및 상기 선박운항정보가 이용되어 임의의 선박에
대한 속도, 임의의 선박에 대한 이동패턴 및 상기 관심영역에서 선박개수가 생
성되고, 임의의 선박에 대한 속도의 변화, 임의의 선박에 대한 이동패턴의 변
화 및 상기 관심영역에서 선박개수의 변화에 따라 이상이 탐지되는 이상 탐지
단계를 포함하는 관제 데이터를 이용한 해상 교통 이상 탐지 방법 및 이를 수
행하는 프로그램이 기록된 컴퓨터 판독이 가능한 기록매체에 관한 것이다.
【대표도
Mesozooplankton Community Structure and Indicator Species in Relation to Seasonal Hydrography in the Yellow Sea and Northern East China Sea
No full textThis study investigated variation in mesozooplankton community structure and indicator species in the Yellow Sea and northern East China Sea, based on four surveys conducted at different times of year. Total mesozooplankton abundance ranged from 1063 to 4515 ind. m−3, and dry weight ranged from 23.3 to 44.6 mg m−3, with higher values observed in May and August compared to October and January. Redundancy analysis explained a modest fraction of the variation in community structure (17.6% in total; Axis 1: 10.5%, Axis 2: 4.6%), with temperature, salinity, and chlorophyll a jointly contributing to the observed gradients. Cluster and indicator species analyses delineated three ecologically distinct regions: (1) a neritic coastal area dominated by coastal copepods and meroplankton; (2) a cold-water region associated with the Yellow Sea Bottom Cold Water (YSBCW); and (3) a warm offshore region influenced by the Jeju and Yellow Sea Warm Currents. Oithona atlantica was consistently linked to the YSBCW, suggesting its potential as a biological indicator of cold-water mass, whereas Clausocalanus minor was confined to warm offshore waters and reflected the seasonal northward expansion of warm currents. These findings demonstrate a clear coupling between mesozooplankton community dynamics and hydrographic conditions during the survey periods.11Nsciescopu
From Downcycling to Valorization: Advancing Value Cascading of Fish By-products in Korea's Circular Bioeconomy
No full text2
Impact of the climate change on Ecklonia cava-dominated kelp forest in South Korea
No full textThe impacts of climate change are global, with significant regional variations and water temperature is a strong indicator. South Korea, located in the northern part of the East China Sea, has been reported as one of most rapidly warming areas globally. Kelp forests predominantly consisted in Ecklonia cava, a perennial endemic macroalga, which provides ecologically diverse habitats and constitutes economically significant ecosystems in Korea and Japan. In this study, we examined the variability characteristics of E. cava as a result of the impact of climate change. When cultivated under temperature-specific conditions, E. cava exhibited the most rapid growth at 15°C, with growth inhibited as water temperature escalated. This suggests that the growth of the natural population may be negatively affected, given that the minimum water temperature of winter in the southern part of Korea is increasingly above 15°C. Moreover, we identified the indiscriminate feeding activity of tropical fish herbivores from the study area with the significant increase in water temperature in November 2023, and confirmed E. cava with severe damage (i.e., reduced blade length and bite marks). However, September to November has been identified as the only annual reproductive peak for this kelp species. The results of this study suggest that the decline of native E. cava in Korean waters is anticipated due to the synergistic impacts of water temperature and non-indigenous herbivores by climate change.1