• 한국해양학회지
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• v.5 no.1
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• pp.14-29
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• 1970

Tidal variations of various chemical constituents in the laver bed sea waters in Wan Do Gun were determined over one spring tidal cycle from Oct. 1968 to Feb. 1969. Total ranges and means of the contents at Pyung-il Do and Wan Do are as follows. Although the average monthly variations of each content at Pyung-il Do were similar to those at Wan Do, most of the contents at Pyung-il Do were at a slightly higher level than at Wan Do. The values of silicate-silicon, phosphate- phosphorus and soluble iron, however, showed high levels at Wan Do. Chlorinity, magnesium, calcium, dissolved oxygen, silicate-silicon and phosphate-phosphorus contents increased from Oct. 1968 to Feb. 1969, though the content of soluble iron decreased before December and slightly increased in January and February. The average monthly variations of ammonia-nitrogen and nitrate-nitrogen contents were irregular. The nitrite-nitrogen content appeared in trace amounts in the months with a comparatively high water temperature, i.e., October and November, but in midwinter it was undetected. The ranges of the tidal variations of the contents of each chemical constituent were not significantly wide, though the contents varied excessively by the hour, and this may show the irregularity of the water quality in Wan Do Gun coastal area. As a rule, no regular tidal variation of the chlorinity was observed except slightly decreased value at ebb tide at Wan Do. In general, although the pattern of the variations of calcium and magnesium contents were similar to that of the chlorinity, no definite relationships between these constituents and chlorinity were observed. Tidal variations of the dissolved oxygen content, nutrient salts and soluble iron were irregular.

• 한국해양학회지
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• v.2 no.1_2
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• pp.24-33
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• 1967

The variations of monthly mean sea levels along the coast of Korea anre studied graphic and harmonic methods with the data from 9 tides stations and compared with the variations of atmospheric pressure and the changes in density of sea water measured near some of the stations. The monthly mean sea level generally rises in Summer to Autumn, and falls in Winter to Spring and its range is from 20 cm to 50 cm. The variation of monthly mean sea level is of annual type, having one maximum and one minimum. The semi-range of annual components is 10.5 cm at Pusan and increases to the north in the west coast, to 20.8 cm at Inchon. It's phase is, on the whole, similar for the entire coast with about 210 (middle of August), except at Inchon, 200 . The variation of monthly mean sea level is mainly isostatic, or caused by those of sea water density and atmospheric pressure. Especially, the steric effect is predominant on the south- east coast around Pusan. However, in shallow long bays and estuaries on the west coast, the river runoff effect as well as local wind effect is also considerable. Magnitudes of annual variations at each stations are not constant, but widely variable from year to year. On the east and south coast, especially at Ulneungdo and Pusan the variations are large, which seem to be connected with the shifting of main current axes or current patterns in the offing.

• The Research Journal of the Costume Culture
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• v.31 no.5
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• pp.669-691
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• 2023

This study aims to analyze the variations in online clothing purchasing patterns based on demographic attributes and purchasing behavior. The survey subjects comprised individuals in their 10s to 50s who had prior experience with online shopping. The survey was conducted in Gyungnam from May to June 2022. A total of 397 questionnaires were analyzed using the χ²-test statistical method. The analysis of clothing purchase type based on demographic characteristics revealed differences in terms of gender, marital status, age, monthly income, and occupation. Notably, when analyzed by demographic characteristics and clothing purchase types, monthly online purchase frequency displayed significant differences in marital status, age, and occupation. Similarly, monthly purchase amounts through online platforms exhibited significant variations based on marital status, age, monthly income, and occupation. The online fashion platforms, when examined in relation to demographic characteristics and purchase types, showed significant differences across all variables. Clothing purchases by consumers seeking individuality and differentiation exhibited significant differences in age, occupation, and purchase types. Furthermore, the reasons for choosing online platforms for clothing purchases varied significantly based on age and occupation. These findings indicate diverse purchasing behaviors on online platforms influenced by demographic characteristics. These findings can be valuable for effectively segmenting the online fashion market.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.997-1004
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• 1997

The effect of the oceanic condition on variations of the catches of Alaska pollack (Theragra chalcogramma) in the East Sea (the Japan Sea) is examined using monthly catches data of this fish and temperature data during 1972 to 1991. Since 1973 the catches of Alaska pollack have gradually increased, showing a peak in 1981, and then rapidly decreased after 1986. A significant negative correlation was found between variations of the catches and the temperature at 50 m depth offshore Mukho. In 1981, the year of the highest catches in the study period, the water mass in the Eastern Korean Coastal Sea of the East Sea was extremely cold, while the year of poor catch, 1979, was much warmer than the annual mean temperature. The results show that the temperature variations around the Eastern Korean Coastal Sea play an important role in the variations of the catches of Alaska pollack, implying that the effect of the Tsushima Warm Current is also very important.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.869-877
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• 2017

The monthly variations of zooplankton community were investigated at 12 stations near Tongyeong and Namhaedo in the South Sea of Korea from April to July, 2012. Zooplankton samples were collected by a plankton net (RN80) from near the bottom to the surface. Zooplankton community consisted of 97 taxa, and the mean abundance ranged from $213inds.m^{-3}$ in July to $426inds.m^{-3}$ in April. Copepods constituted 38.98% of zooplankton abundance, and included 39 species. Calanus sinicus, Corycaeus affinis, Paracalanus parvus s.l., copepodids, Evadne nordmonni, Podon leuckarti, cirriped nauplii, Muggiacea sp., Diphyes sp., and Zonosagitta bedoti were dominant species. Of these, Calanus sinicus was the most abundant throughout the study period, being constituted 18.6% of total zooplankton abundance. The density variations of dominant species between stations and months were correlated with the environmental factors. Zooplankton community varied with by sampling months, being influenced by monthly oceanographic variations.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.1
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• pp.55-66
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• 1996

One-hour average concentrations of ground-level ozone from around 80 monitoring stations in Korea during 1991 to 1993 were analyzed to examine characteristics of the ozone concentration variations. Two types of variations were observed: one was for the Capital area typified by Kwanghwmun, and the other was for the south and east seashore region typified by Tongkwangyang. In the Capital area including Seoul, Inchon, Kyonggi-do and Chunchon, mean daily 1-hout maximum was the highest in June following high monthly averages in spring. But frequent precipitation prevented further rise of daily maximum in July and August even though there were frequent episodes of high concentration exceeding 100ppb. In the south and east seashore region, average concentration was the highest throughout the year, and daily maximum and minimum simultaneously changed owing to small contributions from photochemical reactions. The typical annual variation was spring peak, summer down, and fall rise. Spring peak accompanied an usual observations of background variations at remote sites in the Northern Hemisphere. Riess of average and daily maximum with lower daily minimum in fall were attributable to photochemical reactions.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.365-366
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• 2004

• Korean Journal of Environmental Biology
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• v.33 no.2
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• pp.230-239
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• 2015

Monthly variations of cirriped larvae near Oryuk islets off Busan were investigated at four stations from January 2012 to January 2013. Zooplankton was vertically collected, using NORPAC net (mouth 45 cm, mesh $200{\mu}m$), from the surface to 1 m above the bottom. 12 species belong to five genera of 4 families were identified including one unidentified species. Cirriped larvae occupied small portion of total zooplankton, ranging 0.02 to 4.1% of total zooplankton densities. The densities varied monthly from $1inds.m^{-3}$ to $715.1inds.m^{-3}$, which was highest in September and lowest in February. Chthamalus challengeri, Balanus glanula, B. improbisus, B. nubilus and Octomeris sulcata were dominant species and accounted for 70.1% of total cirriped larvae. Larval densities of cirripeds between stations were not significantly different (F=0.237, p=0.870). The larval communities were grouped into two groups by cluster analysis. We discussed the distribution patterns of cirriped larvae in relation to oceanographic characteristics in the study area.

• ALGAE
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• v.19 no.4
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• pp.329-337
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• 2004

Monthly variations of phytoplankton communities were conducted to the investigation at five stations in mid and lower parts of the Nakdong River from December 1995 to November 1996. The phytoplankton communities were identified a total 456taxa which were composed of 136 genera, 427 species, 27 varieties and 2 forma. The standing crops of phytoplankton communities ranged from 2.7 to 52.8 (${\times}$10³)cells·ml$^{-1}$ during the investigation periods. Bacillariophyceae was the dominant classes at all stations. The dominant species were 7taxa and the standing crops of these ranged from 18.3 to 95.1% of the standing crops of phytoplankton communities. The dominant species in the mid parts (st. 1, 2) of this river system were benthic species such as Navicula gregaria, N. viridula var. rostellata and Nitzschia palea, however it was planktonic species (Stephan discus hantzschii, Golenkinia radiata) and meroplanktonic species (Aulacoseira ambigua, A. granulata) in the lower parts (st. 3, 4, 5). The seasonal variations of the dominant species in the lower parts were appeared to the planktonic species (S. hantzschii) from winter to spring, and were the meroplanktonic species (A. ambigua and A. granulata) in from summer to fall. The lower parts of the Nakdong river were entropic states because the dominant species were composed A. ambigua, A. granulate and S. hantzschii which were indicators of entropic water quality. The interrelationships between total standing crops and environmental factors(water temperature, pH, NH$_4$, NO$_2$, NO$_3$ and PO$_4$) were low positive or negative coefficients. S. hantzschii had low positive or negative relations with water temperature, NH$_4$, NO$_2$, NO$_3$ and PO$_4$. As the result, the variations of standing crops of phytoplankton were not caused by a single factor but controlled by the complex factors.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.55-64
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• 1978

The present investigations were carried out for the purpose of making clear the fundamental features of the seasonal variations in carrageenan content and its chemical composition. The samples, Chondrus ocellatus, were collected every month from the same locality on the coast of Haewundae from March, 1975 to February, 1976, and analyzed monthly to determine their carrageenan content, sulphate and 3,6-anhydro-D-galactose over a year period. En addition, some chemical characteristics were also tested on the fractions separated by the different concentrations of potassium chloride. In seasonal variation, the maximum carrageenan content occurred from summer through autumn, and the minimum in winter, especially in February. It is noted in the seasonal variations of the sulphate content of total carrageenan and three fractions that the maximums appreared in October and minimums in february. With seasonal variations of percent 3,6-anhydro-D-galactose of total carrageenan and three fractions, maximum values occur in June and minimum values in December. Seasonal variations in sulphate and 3,6-anhydro-D-galactose contents of the three fractions were on the whole similar in mode of variation, and there could be no substancial differences. Seeing seasonal variations in the sulphate and 3,6-anhydro-D-galactose contents of three fractions, carrageenan extracted from the algae gathered in spring shelved higher portion of fraction I than that gathered in autumn. In these respects, it seems that a more weakly gelling k-carrageenan exists in the spring than in the autumn.