E-navigation을 활용한 해상교통관리체계 개선방안에 관한 연구

E-navigation Services for Non-SOLAS Ships

Maritime accident prediction in busan port using machine learning: An integrated approach with maritime accident reports and VTS data

The present study describes the morphology, taxonomy, and distribution of species belonging to the diatom genus Rhizosolenia in Korea's marine coastal waters.From September 2008 to February 2010, we collected phytoplankton samples at 30 sites along the Korean coastline and studied them by light and scanning electron microscopy.We found 6 rhizosolenid genera in our samples: Rhizosolenia, Dactyliosolen, Guinardia, Pseudosolenia, Proboscia, and Neocalyptrella.In the present paper, we studied the following rhizosolenid species and compared them with congeners: R. pungens, R. fallax, R. imbricata, Rhizosolenia sp. 1, and Rhizosolenia sp. 2. The morphology of R. pungens exhibits important diagnostic characteristics in its girdle segment structure in the column and in its external process.To distinguish R. fallax and R. imbricata, the most important characteristics are the striation and the velum structure.R. pungens occurred in our samples all along the Korean coast.Only rarely did we find R. imbricata in the samples and at low abundance.We recorded R. fallax, Rhizosolenia sp. 1 and Rhizosolenia sp. 2 for the first time in Korean waters, but they rarely occurred.

Hypoxia and benthic community recovery in Korean coastal waters

The Sea Traffic Management (STM) Validation Project is a European-based initiative with ambitions to improve maritime safety and efficiency through information sharing in real time. The purpose of this paper is to evaluate the “STM services,” which can be categorized as low-level automated functions designed to improve information exchange between ship and shore. Full-scale simulated scenarios were developed and tested on 16 professional vessel traffic service (VTS) operators comparing VTS operations as they are today with the added STM functionality. Data collection involved observations which assessed the frequency and type of interactions between ships and VTS, followed by questionnaires to provide an overall assessment of the user experience. The results indicate that the frequency and method of communication patterns between VTS operators and ships will be affected by the integration of the STM services. Additional access to navigational information could change the role of VTS operators in traffic situations compared with traditional operations. This paper discusses the findings from a socio-technical systems perspective while also addressing the individual STM services and their potential impact on VTS operations. This research provides valuable information for European VTS centers that could be affected by the implementation of e-Navigation and, specifically, the STM services.

Occurrence and accumulation features of polycyclic aromatic hydrocarbons and synthetic musk compounds in finless porpoises (Neophocaena phocaenoides) from Korean coastal waters

In this study, single-input transfer function model is applied to forecast monthly mean sea surface temperature(SST) in 2010 at Yeosu in Korean coastal waters. As input series, monthly mean air temperature series for ten years(2000-2009) at Yeosu in Korea is used, and Monthly mean SST at Yeosu station in Korean coastal waters is used as output series(the same period of input). To build transfer function model, first, input time series is prewhitened, and then cross-correlation functions between prewhitened input and output series are determined. The cross-correlation functions have just two significant values at time lag at 0 and 1. The lag between input and output series, the order of denominator and the order of numerator of transfer function, (b, r, s) are identified as (0, 1, 0). The selected transfer function model shows that there does not exist the lag between monthly mean air temperature and monthly mean SST, and that transfer function has a first-order autoregressive component for monthly mean SST, and that noise model was identified as . The forecasted values by the selected transfer function model are generally higher than actual SST in 2010 and have 6.4 % mean absolute percentage error(MAPE). The error is 2 % lower than MAPE by ARIMA model. This implies that transfer function model could be more available than ARIMA model in terms of forecasting performance of SST.

In the coastal region of Korea, historical tide harmonic constants were collected. Long-term tides and short-term tides observed by the KHOA were analyzed by a tide harmonic analysis method. Based on the harmonic constants, tidal characteristics such as tide asymmetry in Korean coastal waters were investigated. The harmonic constants obtained from the long-term tide data in the western coast have been used to show the relation between tide variation and reclamation project. amplitudes in the western coast have been decreased and phases were faster. amplitudes also were reduced and phases were faster in overall. In Mokpo and Kunsan tidal nonlinearity is relatively conspicuous. Overall, non-linearity of tidal currents is higher in the tidal channels flowing fast. The tidal non-linearity has increased by the development projects including large reclamation. The flood dominant characteristic in the northern and central part of Korean western coastal waters and the ebb dominant characteristic in the southern part have been intensified. The construction of Saemangeum sea dike has significantly changed the tidal characteristic in Korean western coastal waters.

We have developed a method to identify species in the genus Alexandrium using whole-cell fluorescent in situ hybridization with FITC-labeled oligonucleotide probes that target large subunit ribosomal rRNA molecules. The probes were designed based on the sequence of the rDNA D1-D2 region of Alexandrium species. DNA probes specific for toxic A. tamarense and A. catenella and nontoxic A. affine, A. fraterculus, A. insuetum, and A. pseudogonyaulax, respectively, were applied to vegetative cells of all above Alexandrium species to test the sensitivity of the probes. Each DNA probe hybridized specifically with vegetative cells of the corresponding Alexandrium species and showed no cross-reactivity to noncorresponding Alexandrium species. In addition, no cross-reactivity of the probes was observed in experiments using concentrated natural seawater samples. The TAMAD2 probe, which is highly specific to A. tamarense, a common toxic species in Korean coastal waters, provides a simple and reliable molecular tool for identification of toxic Alexandrium species.

We report the first observation of fluorescently labeled bacteria (FLB) ingestion by the cells of MR-MAL01, a temperate strain of the marine photosynthetic ciliate Myrionecta rubra Jankowski 1976 (=Mesodinium rubrum Lohmann 1908). We also investigated the time course of ingestion and digestion of bacteria as well as the ingestion rates at 3 different light intensities. In the stationary phase of growth with ambient bacterial abundance (1.4 x 10 6 cells ml -1 ) under conditions of 15°C and 60 μE m -2 s -1 , the rates of FLB uptake and disappearance of M. rubra MR-MAL01 cells were 7.6 and 5.3 FLB grazer -1 h -1 , respectively. The ingestion rate of M. rubra in cultures was calculated to be 53 bacteria grazer -1 h -1 . The initial abundance of M. rubra (ca. 1.0 x 10 4 cells ml -1 ) in the ingestion-digestion experiment was comparable to the natural abundance during the M. rubra red tide in Korean coastal waters. The bacterivory rate of M. rubra increased gradually as light intensity decreased from 200 to 0 μE m -2 s -1 ; this might enable the photosynthetic M. rubra to survive under intermittently light-limiting conditions. The present study showed a novel phenomenon of the ingestion of bacterial cells by M. rubra and the light-affected bacterivory rates of the common red tide ciliate.

Three clades of Pseudo-nitzschia pungens, determined by the internal transcribed space (ITS) region, are distributed throughout the world. We studied 15 P.pungens clones from various geographical locations and confirmed the existence of the three clades within P.pungens, based on ITS sequencing and described the three subgroups (IIIaa, IIIab, and IIIb) of clade III. Clade III (clade IIIaa) populations were reported for the first time in Korean coastal waters and the East China Sea. In morphometric analysis, we found the ultrastructural differences in the number of fibulae, striae, and poroids that separate the three clades. We carried out physiological tests on nine clones belonging to the three clades growing under various culture conditions. In temperature tests, only clade III clones could not grow at lower temperatures (10°C and 15°C), although clade I and II clones grew well. The estimated optimal growth range of clade I clones was wider than that of clades II and III. Clade II clones were considered to be adapted to lower temperatures and clade III to higher temperatures. In salinity tests, clade II and III clones did not grow well at a salinity of 40. Clade I clones were regarded as euryhaline and clade II and III clones were stenohaline. This supports the hypothesis that P.pungens clades have different ecophysiological characteristics based on their habitats. Our data show that physiological and morphological features are correlated with genetic intraspecific differentiation in P.pungens.

Long-term changes in the concentrations of nutrients in the marginal seas (Yellow Sea, East China Sea, and East/Japan Sea) neighboring the Korean Peninsula

ABSTRACTHarmful algal blooms have caused critical problems worldwide because they pose serious threats to human health and aquatic ecosystems. In particular, red tide blooms of Cochlodinium polykrikoides have caused serious damage to aquaculture in Korean coastal waters. In this study, multiple linear regression, regression tree (RT), and Random Forest models were applied to detect C. polykrikoides blooms in coastal waters. Five types of input data sets were implemented to test the performance of the models. The observed number of C. polykrikoides cells and reflectance data from Geostationary Ocean Color Imager images obtained in a 3-year period (2013–2015) were used to train and validate the models. The RT model demonstrated the best prediction performance when four bands and three-band ratio data were simultaneously used as input data. The results obtained via iterative model development with randomly chosen input data indicate that the recognition of patterns in the training data caused variations in the prediction performance. This work provides useful tools for reliable estimation of the number of C. polykrikoides cells using reasonable coastal water reflectance data sets. It is expected that administrators and decision-makers whose work is associated with coastal waters will be able to easily access and manipulate the RT model.

Thalassiosira constricta was first described from Tromsø in the Norwegian Sea. The species was placed in the large and morphologically diverse genus Thalassiosira based on the presence of classical features of that genus, including the formation of chains held together by β-chitin threads extruded from central fultoportulae. We recently discovered T. constricta in Korean coastal waters near Sinsi Island. Detailed morphological analyses revealed the following cell wall features: i) cells arranged in chains, with adjacent cells directly abutting one another or distinctly separated and linked by β-chitin threads extruded from a central cluster of 0–14 fultoportulae, ii) delicate, biseriate poroid areolae along radial ribs on the valve face and coarse loculate areolae on the valve mantle, iii) a cingulum structure consisting of finely perforated valvocoupla and copula and scratched pleurae, iv) distinct antiligula on the valve, v) a single ring of marginal fultoportulae, vi) one rimoportula located within the ring of marginal fultoportulae, vii) fultoportulae with internal extensions that lack opercula, and viii) fultoportulate with four fully exposed satellite pores, each in a depression and surrounded by a defined cowling. Phylogenetic analysis of nuclear and plastid markers revealed a sister relationship with Bacterosira bathyomphala. Based on these findings, we transfer T. constricta to Bacterosira as Bacterosira constricta comb. nov. and offer an emended the description of the genus Bacterosira, which appears to be one of only a few monophyletic marine genera in Thalassiosirales.

Tuberlatum coatsi gen. n., sp. n. (Alveolata, Perkinsozoa), a New Parasitoid with Short Germ Tubes Infecting Marine Dinoflagellates