• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.20-28
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• 2005

Species composition and seasonal variation of decapod crustacean assemblage in Hampyeong Bay, Korea were examined. Sampling was monthly made by a shrimp trawl between March 2003 to February 2004. A total of 39 species of 20 families were collected. Of these, Latreutes planirostris, Palaemon gravieri, Parapenaeopsis tenella, Exopalaemon carinicauda, Charybdis japonica, Trachysalambria curvirostris and Palaemon macrodactylus were dominant species comprising $84.3\%$ of the total number of individuals. Charybdis japonica, P. gravieri, Oratosquilla oratoria, E. carinicauda, T curvirostris, Metapenaeus joyneri and P. tenella represented $90.6\%$ of the total biomass. While total abundance (number of individuals) was high in spring, total biomass and species richness (number of species) and diversity were high in summer. Cluster analysis, based on monthly abundance data of the 14 most common species, showed that the species were separated into three different groups. Group A composed of Leptochela gracilis, Alpheus japonicus, Crangon uritai, P. macrodactylus, E. carinicauda, P. gravieri, O. oratoria, C. japonica, which were year round residents, group B M. joyneri, T. curvirostris and P. tenella, which were abundant in summer, and group C Crangon hakodatei, Latreutes anoplonyx and L. planirostris, which were abundant in winter. Principal component analysis revealed that seasonal variation in the decapod crustacean assemblage was attributed to the abundance of temporal species such as penaeid shrimps, which were abundant in summer, due to seasonal variation of water temperature and reproductive pattern.

• Journal of Coastal Disaster Prevention
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• v.5 no.4
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• pp.183-192
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• 2018

In recent years, coastal areas have been suffering from coastal erosion, such as destruction of coastal roads and military facilities. In this study, the Delft3D model was used to analyze the sediment transport pattern due to seasonal characteristics of summer and winter waves in Anmok beach of the East coast. Typhoon and high waves are mainly are coming from ENE direction in the summer season and the flows occur in the northward. In winter, high waves are incident from NE and the flows occur in the southward. These seasonal patterns were simulated by using Delft3D model. As for model input, reanalysis wave data of the past 38 years were used, and the seasonal patterns were analyzed by dividing the whole year into summer and winter season. The grid point of the 38 year reanalysis data is far from the Anmok beach, so the three model grid systems (wide grid -> intermediate grid -> detailed grid) are constructed. Most of the flows in the NW direction occurred in summer, but erosion and deposition was alternated along the coastline. In winter, sediment was deposited near Gangnung Port due to the southern flow and the southern port. Strong winter waves compared to summer tend to cause deposition around Gangnung Port throughout the year.

• Asian Journal of Atmospheric Environment
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• v.9 no.1
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• pp.66-77
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• 2015

In order to survey the seasonal variation of the chemical composition of particulate matter of $2.5{\mu}m$ or less ($PM_{2.5}$), $PM_{2.5}$ was sampled from 8 February 2013 to 31 March 2014 in an industrial area of Chiba Prefecture, Japan. Chemical measurements of the sample included: ionic components ($Na^+$, $NH_4{^+}$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $Cl^-$, $NO_3{^-}$ and $SO_4{^{2-}}$), carbonaceous components - organic carbon (OC) and elemental carbon (EC), and water-soluble organic carbon (WSOC). Also, secondary organic carbon (SOC) was measured based using the EC tracer method, and char-EC and soot-EC were calculated from the analytical results. The data obtained were interpreted in terms of temporal variation. Of the overall mean value of $PM_{2.5}$ mass concentration obtained during the study period, ionic components, OC and EC accounted for 45.3%, 19.7%, and 8.0%, respectively. $NO_3{^-}$ showed a unique seasonal distribution pattern due to a dependence on temperature and absolute humidity. It was estimated that an approximate temperature of $14^{\circ}C$, and absolute humidity of $7g/m^3$ were critical for the reversible reaction of $NH_4NO_3(p){\leftrightharpoons}NH_3(g)+HNO_3(g)$. The amount of OC and EC contributing to the monthly $PM_{2.5}$ mass concentration was higher in autumn and winter compared to spring and summer. This result could be attributed to the impact of burning biomass, since WSOC and the ratio of char-EC/soot-EC showed a similar pattern during the corresponding period. From the comparison of monthly WSOC/OC values, a maximum ratio of 83% was obtained in August (summer). The WSOC and estimated SOC levels derived from the EC tracer method correlated (R=0.77) in summer. The high occurrence of WSOC during summer was mainly due to the formation of SOC by photochemical reactions. Through long-term observation of $PM_{2.5}$ chemical components, we established that the degree to which the above-mentioned factors influence $PM_{2.5}$ composition, fluctuates with seasonal changes.

• Sleep Medicine and Psychophysiology
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• v.14 no.1
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• pp.26-32
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• 2007

Objectives: Angiotensin-converting enzyme (ACE) gene polymorphism has been reported to be associated with depression and therapeutic outcome in depression. The purpose of this study was to determine whether ACE gene polymorphism is associated with seasonal variation in mood and behavior in a young Korean college student sample. Methods: 297 young Korean medical students were recruited in this study. All subjects were free of major medical and psychiatric problems. They were genotyped for the ACE gene polymorphism and evaluated the seasonal variation in mood and behavior by the Seasonality Pattern Assessment Questionnaire (SPAQ). Results: Global Seasonality Score (GSS) of SPAQ between three genotypes were not different. However, comparison of the group that showed seasonality of mood and behavior during winter with the group that did not showed seasonality indicated significant difference in genotype distribution ($x^2=6.79$, p=0.034). The D allele non-carrier (ll genotype) frequency was significantly higher in winter seasonality group than non-seasonality group ($x^2=6.59$, p=0.010；odds ratio [OR]=2.27, 95% confidence interval [CI] 1.20-4.28). Conclusion: These results suggest that the ACE gene polymorphism is related to winter-type seasonality in a Korean population.

• Ocean and Polar Research
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• v.34 no.4
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• pp.403-411
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• 2012

Among others, a question that has long been unanswered is why the seasonal variation of volume transport is larger in the Soya and Korea/Tsushima Straits than in the Tsugaru Strait. An attempt is made to answer this question in terms of the island rule with friction being taken into account. The problem is idealized as a simple model. The model results indicate that volume transport through a channel is determined not only by the circulation created around the adjacent island but also by those created around the neighboring islands farther away. The latter is due to the presence of bottom friction in the channels. The volume transports through the Korea/Tsushima, Tsugaru and Soya Straits estimated from the model using observed wind data show the general pattern of observed seasonality, although they contain large errors associated with the uncertain frictional parameter employed in the model. The model indicates that the observed seasonality arises essentially from the fact that wind stress curl changes its sign, from negative in the summer to positive in winter, following a large fluctuation of zero-stress curl latitude east of Hokkaido.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.276-282
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• 2015

Seasonal variation in the contents of sugars (fructose, glucose, and sucrose) in the floret, leaf, and stem of broccoli were studied in ten commercial broccoli cultivars. Plants were grown in the spring and fall seasons in 2011. In both seasons, glucose was the major constituent, comprising about 50% of the total sugar content in the floret and leaf tissue of most cultivars, whereas the broccoli stem showed an unusual pattern of accumulation. Sucrose exhibited greater cultivar dependency as well as seasonal variation compared to fructose and glucose in floret and leaf tissues. The floret tissue had a higher total content of sugar in the spring compared to the fall due to an increase in glucose and fructose. However, most of the leaf and stem tissues of broccoli had a higher total sugar content in the fall compared to the spring. Furthermore, stem and leaf tissues possessed a relatively higher total sugar content compared to floret tissue in both seasons. 'Grandeur' broccoli contained a significantly greater amount of total sugar in both floret and leaf tissues in both seasons, whereas 'YuDoRi No.1' broccoli exhibited the highest total content of sugar in stem tissue. At overall, the results showed significant influences of genotype, plant part and growing season on sugar content in broccoli.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.10
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• pp.1257-1264
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• 2018

This paper proposes Autoregressive Integrated Moving Average (ARIMA)-based forecasting algorithms using meteorological indices to predict seasonal peak load. First of all, this paper observes a seasonal pattern of the peak load that appears intensively in winter and summer, and generates ARIMA models to predict the peak load of summer and winter. In addition, this paper also proposes hybrid ARIMA-based models (ARIMA-Hybrid) using a discomfort index and a sensible temperature to enhance the conventional ARIMA model. To verify the proposed algorithm, both ARIMA and ARIMA-Hybrid models are developed based on peak load data obtained from 2006 to 2015 and their forecasting results are compared by using the peak load in 2016. The simulation result indicates that the proposed ARIMA-Hybrid models shows the relatively improved performance than the conventional ARIMA model.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.1
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• pp.11-23
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• 2002

The concentrations of aldehydes were measured in downtown area of Buchun and Kwanghwamoon of Seoul from October 1997 to August 1998 using 2-series impingers. The data have been analysed to identify the seasonal pattern of aldehyde sources in metropolitan areas. The measured concentration (in ppbv) of aldehydes were 8.86 $\pm$ 7.28 HCHO (formaldehyde) and 7.79$\pm$7.29 $CH_3$CHO (acetaldehyde) in Buchun, while recording 10.13$\pm$8.58 (HCHO) and 7.64$\pm$6.65 ($CH_3$CHO) in Kwanghwamoon. Their diurnal variation patterns showed significant increase of HCHO and $CH_3$CHO concentration in early afternoon, indicating an increase in secondary sources. Their concentrations however decreased in the nighttime, regardless of seasons. The strength of correlations between certain pairs such as (1) HCHO and CO and (2) $CH_3$CHO and CO were generally high during the winter months (0.64< r < 0.84), suggesting the possibility of similar source processes for HCHO, $CH_3$CHO and CO. On the other hand during the summer months, their correlations are frequently lower than winter months. We suggested that the complexity of source/sink processes during the summer period may reduce the correlations between aldehyde and CO.

• Sleep Medicine and Psychophysiology
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• v.5 no.2
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• pp.202-209
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• 1998

Authors report the findings of nocturnal polysomnography and multiple sleep latency test(MSLT) before and after morning light treatment in a winter depressive patient with hypersomnia. On polysomnographic recordings, the sleep pattern of this case before light treatment was similar to that of narcolepsy exhibited, sleep onset REM period(SOREMP). After treatment, the shortened REM latency changed to normal condition, but, deep sleep percentage did not changed, and stage 4 sleep percentage was decreased. Depressive symptoms were improved on clinical interview with Hamilton Depressive Rating Scale. Sleep log showed shortened sleep latency and reduced sleep duration. These findings suggest that although light treatment could alter the sleep structure in seasonal affective disorder with hypersomnia, it does not necessarily imply that antidepressant response of light treatment is result of change of sleep structure.

• Journal of Plant Biology
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• v.28 no.2
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• pp.149-164
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• 1985

Intertidal algal community of Muchangpo in western coast of Korea was investigated qualitatively and quantitatively. Seasonal changes of algal occurrence, dominant species in cover, vertical zonation pattern and biomass were analysed. A total of sixty-four species of marine algae, one blue-green alga, three green algae, nineteen brown algae and forty-one red algae, were identified. The dominant species in cover were Sargassum thunbergii, Gelidium divaricatum and Pelvetia siliquosa throughout the year. Gloiopeltis furcata was abundant at upper and middle littoral zones and Corallina pilulifera at lower littoral zone. Classification by unweighted pair-group average method and ordination by reciprocal averaging based on the cover data indicated that, on the whole, the intertidal algal vegetation showed different patterns along tidal levels. Seasonal fluctuations of mean biomass were 57.2~92.8 g-dry/$m^2$, and the highest in summer and the lowest in spring season. Seasonal change of community structure was also discussed.