• 환경생물
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• 제20권3호
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• pp.268-275
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• 2002

Seasonal variation in reproductive condition of the Pacific oyster Crassostrea gigas was investigated from a suspended cultured oyster population in Gosung Bay, South Korea using histological techniques, Gametogenesis of oysters initiated in February when water temperature reached 11 to $13^\circ{C}$. Increase in oocyte size and the number resulting in follicle expansion was observed from March to May First spawning of oysters observed in mid Jun when the surface water temperature reached 22 to $25^\circ{C}$. Spawning activity of oysters extended from mid June to late September with two marked spawning peaks in June and August. Most oysters collected from October to December exhibited few residual eggs in packed follicles exhibiting a typical spent condition. No gametes were observed from December to February from oysters collected in the Bay. Gonadal development of oysters in the Bay seemed to follow a seasonal fluctuation in environmental conditions such as water temperature and food availability in the water column. Spawning of oysters in late June was in part associated with sudden drop in salinity due to vast amount of freshwater input in the Bay after the summer flooding. Sex ratio of oysters was 59.5% male and 39.8% female. Less than 1 percent (0.6%) of the oysters examined were hermaphrodite; few eggs were observed in testis.

• 원예과학기술지
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• 제33권2호
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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.

• 한국수산과학회지
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• 제47권5호
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• pp.645-653
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• 2014

We examined seasonal variation in fish species composition in coastal waters near Wolseong Nuclear Power Plant in the East Sea of Korea. A total of 72 species, 39 families, 14 orders, 46,214 individuals, and 4,639,667 g were collected. Glyptocephalus stelleri was the most dominant species by number of individuals (35%), followed by Clupea pallasii (26%). Liparis tanakai and Lophius litulon were the dominant species by biomass, accounting for 46% and 28%, respectively. We showed that bottom salinity and temperature are the most important environmental factors influencing fish species composition. Although bottom salinity did not differ statistically among seasons or stations, we detected some variation among stations. Additionally, bottom temperature differed among seasons and stations (P<0.05), affecting numbers of individuals and biomass. Thus, seasonal variation in fish assemblages can be classified into two groups: spring/summer and autumn/winter.

• 수산해양교육연구
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• 제27권1호
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• pp.300-307
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• 2015

Seasonal variation in marine macroalgal community structure was examined at the intertidal zones of Geumgap, Jindo, Korea, from October 2013 to August 2014. In total, 56 macroalgal species were identified, including 9 green, 12 brown, and 35 red algae. Annual seaweed biomass was 548.96 g wet wt. /$m^2$ with seasonal range between 371.08 g wet wt. /$m^2$ at summer and 32.91 g wet wt. /$m^2$ at winter. The dominant seaweed in terms of biomass was Sargassum thunbergii and subdominant species were Gelidium elegans, Sargassum fusiforme, and Ishige okamurae. The vertical distribution of seaweeds from the upper to lower intertidal zones was Gloiopeltis spp., Ulva spp.- S. thunbergii, S. fusiforme, Ishige okamurae - S. thunbergii, S. fusiforme, G. elegans. Annual seaweed coverage, richness index (R), evenness index (J'), and diversity index (H') values were 27.95%, 6.10, 0.38, and 1.38, respectively. Coarsely branched form was the most dominant functional group in terms of species number and biomass among benthic macroalgal species.

• 한국수산과학회지
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• 제37권1호
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• pp.65-72
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• 2004

Fish catch by a set net in Hamdeuk fishing ground off Jeju Island were studied to determine seasonal variation of species composition and catch from 1998 to 2000. A total 72,022.9 kg was caught during the survey period, including Scomber japonicus and Trachurus japonicus of $76.4\%$ in the total. The other dominant species were Siganus fuscescens, Loligo chinesis, Seriola dumerili, Sepioteuthis lessoniana, Sardinops melanostictus, and Seriola lalandi accounting to $20.0\%$ of the total. The fishing period conducted by a set net in Hamdeuk fishing ground were from May to November. The catch by a set net were higher in summer than in spring and autumn and closely related with the seasonal variation of sea water temperature. The catch was higher in 1998 than In 1999 and 2000, which was related to the sea water temperature in fishing ground.

• 한국물환경학회지
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• 제34권1호
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• pp.67-76
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• 2018

There are 34 mega-cities with a population of more than 10 million in the world. One of the highly populated cities in the world is Seoul in South Korea. Seoul receives $1,140million\;m^3/year$ for domestic water, $2million\;m^3/year$ for agricultural water and $6million\;m^3/year$ for industrial water from multi-purpose dams. The maintenance water used for water conservation, ecosystem protection and landscape preservation is $158million\;m^3/year$, which is supplied from natural precipitation. Recently, the use of the other water for preservation of water quality and ecosystem protection in urban areas is increasing. The objectives of this study is to develop the seasonal forecast method of environmental water in urban areas (Seoul, Daejeon, Gwangju, Busan) and to evaluate its predictability. In order to estimate the seasonal outlook information of environmental water from Land Surface Model (LSM), we used the observation weather data of Automated Synoptic Observing System (ASOS) sites, forecast and hind cast data of GloSea5. In the past 30 years (1985 ~ 2014), precipitation, natural runoff and Urban Environmental Water Index (UEI) were analyzed in the 4 urban areas. We calculated the seasonal outlook values of the UEI based on GloSea5 for 2015 year and compared it to UEI based on observed data. The seasonal outlook of UEI in urban areas presented high predictability in the spring, autumn and winter. Studies have depicted that the proposed UEI will be useful for evaluating urban environmental water and the predictability of UEI using GloSea5 forecast data is likely to be high in the order of autumn, winter, spring and summer.

• 한국환경과학회지
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• 제23권9호
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• pp.1563-1572
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• 2014

The autecology of the Zostera marina and Z. japonica was studied in populations growing in the same locality (Sagumi Bay, southwestern coast of Korea). Environmental factors and plant characteristics were examined monthly from August 2008 to September 2011. Along intertidal zone, Z. japonica (0.1-0.5 m above mean lower low water, MLLW) occurred above Z. marina (0.5-2.5 m MLLW). Tidal exposure at low tide during day was the highest in the spring and the lowest in the summer. Underwater Irradiance showed seasonal fluctuation that was the highest in spring and summer caused by tidal pattern. Strong seasonal patterns in water temperature appeared to control the seasonal variations in morphology, biomass and leaf growth. The seasonal pattern of Z. japonica resembled that of the Z. marina in morphological characteristics, above-and below-ground biomass, whereas it differed in shoot density and leaf elongation. Despite some similarities in seasonal growth patterns, the patterns of Z. japonica were lagged by 2 month of Z. marina. Seasonal variation in the above biomass of Z. marina was caused by changes in density and plant size, whereas that of Z. japonica was mainly caused by changes in shoot density. Zostera marina was more sensitive to high temperatures than Z. japonica, and the increasing water temperature during the summer became the factor that inhibits the growth of the Z. marina. Zostera Japonica, there is no clear change according to the amount of the light. It is because its habitat locates above that of Zostera marina so that the amount of the light that is necessary to growth is enough and in this condition, any preventing factor does not seem to work at all. Although underwater light getting into Zostera marina's habitat is very low level and there is no any hindrance to the survival of them, it prevents them from their productivity a bit.

• 한국콘텐츠학회논문지
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• 제7권10호
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• pp.293-301
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• 2007

최근 호텔기업에서 식음료부문이 객실보다 더 많은 수익을 창출하는 부서로 인식하면서 수익성 관리와 더불어 다각적이고 과학적인 경영정책이 요구된다. 특히 기술의 발전과 정보의 공유화 등으로 인하여 호텔 서비스의 동질화 현상이 심화됨에 따라서 차별화 기회가 감소되고 있다. 이에 경쟁력 강화를 위하여 신규고객 창출 및 기존고객 유지는 매우 중요하다고 할수 있다. 이러한 고객관리와 매출증진을 위하여 식음료부서는 프로모션행사를 실시하는데, 본 연구는 이러한 프로모션 메뉴의 일종인 일식레스토랑의 계절성메뉴를 통하여 계절성메뉴 및 일식당메뉴에 대한 이론적 고찰을 통하여 개념 재정리, 계절성메뉴가 고객만족에 미치는 영향에 대한 실증분석을 통하여 영업활성화 방안모색 및 효율적인 계절성메뉴 관리방안을 제시하는데 연구의 목적을 두었다.

• 한국의류산업학회지
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• 제11권5호
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• pp.833-839
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• 2009

This study was to investigate the human's physiological responses and subjective sensations with wear trial through seasonal condition by age. Climate chamber was set $5^{\circ}C$, RH 45% for winter and $30^{\circ}C$, RH 65% for summer condition. Thirty male subjects were volunteered consisted of 10 people in their 20s, 40s, and 60s. In this study physiological responses such as rectal temperature, skin temperature, clothing microclimate, heart rate and blood pressure were measured. As for age, 60s was the highest in rectal temperature regardless of seasonal condition. In skin temperature, 40s was the highest in winter and 20s was the highest in summer. In clothing microclimate temperature and heart rate, 20s was the highest regardless of seasonal condition. And blood pressure was appeared the highest in 20s regardless of seasonal condition. Subjective sensations such as temperature sensation, wetness sensation and thermal comfort were measured. The subjects revealed that temperature sensation was higher 20s than 60s. Compare of other age group, 60s felt colder in the same environment and clothing. It suggested that temperature susceptibility in 60s became weakened showing no change sensation during the cold exposure. Wetness sensation was higher 20s than 60s. Thermal comfort of 60s was felt more discomfortable than any other age group. This means require the supplement of a suitable clothing in order to adjust to change of environmental conditions.

• 대한가정학회지
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• 제47권3호
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• pp.67-77
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• 2009

This study developed a model economic education program for young children related to Korean seasonal customs. The model was developed via literature reviews and survey research concerning teachers’' recognition of ‘'early childhood economic education’', consultations with professionals in the field, and testing and modifying the program. The goals of the model program were: teaching children to understand basic economic concepts, helping children to develop an economic attitude that emphasizes interdependence, and acknowledging the importance of eco-friendly economic values. The model includes three educational areas and 21 content areas including understanding the concept of exchange, sharing and cooperation, and circulation with nature. This study also developed 37 early childhood economic education activities using the teaching and learning methods of experiencing nature, virtual experience, real life experience, and traditional games experience.