• Journal of Environmental Impact Assessment
• /
• v.20 no.4
• /
• pp.455-464
• /
• 2011

The purpose of this study is to clarify correlations between soil environments and the growth of trees in forests and thereon analyze effects of seasonal changes in such environments on such growth. To determine seasonal factors of soil affecting the Tree Vitality of Pinus thunbergii, first of all, the study designated the Tree Vitality as a dependent variable and soil hardness, moisture, pH, K, Na, Mg and Ca as independent variables. Then the study performed Pearson's coefficient analysis. To clarify what soil factors influence the seasonal growth of Pinus thunbergii multiple regression analysis is carried out, and findings are as follow; the growth of Pinus thunbergii was basically influenced by pH, followed by soil hardness in spring, K, followed by moisture in summer, and by soil hardness in winter. However, no soil factors affected the vitality at the significance level of 5% for t.

• Current Research on Agriculture and Life Sciences
• /
• v.32 no.4
• /
• pp.175-177
• /
• 2014

This is the first report describing the seasonal conditions affecting shoot regeneration by the chrysanthemum cv. Baeksun. The shoot regeneration from petal explants was found to be more favorable from September to December, reaching the highest values in December. In addition, the quality of the shoots was also influenced according to the season of the explant collection, where healthy and uniform plants were derived from the explants collected in December. Choosing the proper season for explant collection affected the successive plant growth parameters (i.e., plant height and fresh weight). Thus, the current results strongly suggest that season plays an important role in plant tissue culturing, which is an essential tool for micropropagation and Agro-bacterium-mediated genetic transformation studies.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.183-183
• /
• 2017

Pan evaporation (Epan) is an important indicator of water and energy balance. Despite global warming, decreasing annual Epan has been reported across different continents over last decades, which is claimed as pan evaporation paradox. However, such trend is not necessarily found in seasonal data because the level of contributions on Epan vary among meteorological components. This study investigates long-term trend in seasonal pan evaporation from 1908 to 2016 across South Korea. Meteorological variables including air temperature (Tair), wind speed (U), vapor pressure deficit (VPD), and solar radiation (Rs) are selected to quantify the effects of individual contributing factor to Epan. We found overall decreasing trend in Epan, which agrees with earlier studies. However, mixed tendencies between seasons due to variation of dominant factor contributing Epan were found. We also evaluated the reference evapotranspiration based on Penman-Monteith method and compared this with Epan to better understand the physics behind the evaporation paradox.

• The Journal of the Korea Contents Association
• /
• v.7 no.10
• /
• pp.293-301
• /
• 2007

As hotel industry lately recognize that food and drink industry produces more profits than hotel rooms, multi-various and scientific management policies are required along with the management of profitability. Particularly, as hotel services have become more alike due to the development of technology and sharing information, opportunities for differentiation have decreased. In light of such circumstances, creating new customers and maintaining existing customers are very important to reinforce competitiveness. To have such a management of customers and to increase sales, promotional events are carried out in the department of food and drink. This study aims to conduct theoretical investigation of seasonal menu and Japanese restaurant menu in seasonal menu of Japanese restaurants that is a type of such promotional menu. The purposes of the study are to reorganize the concepts and to seek for methods of sales promotion and to suggest efficient management of Japanese restaurant seasonal menu by conducting empirical analysis on the effects of seasonal menu on customers and their intention to reorder.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.9 no.5
• /
• pp.103-113
• /
• 2009

In this study, we separated the precipitation zones using the geographic location of stations and precipitation characteristics (monthly, seasonal, annual) in Gangwon province. Precipitation data of 66 weather stations (meterological office: 11 locations, auto weather system (AWS): 55 places) were used, and statistical method, K-means cluster method, was conducted for division of the precipitation regions. As the results of regional classification, the five zones of precipitation (Yongdong: 1 region, Youngseo: 4 regions) were separated. Seasonal average precipitation in spring is similar throughout Gangwon Province, seasonal average precipitation in summer has high values at Youngseo, and seasonal average precipitation in autumn and winter have high values at Youngdong. The some areas, the vicinity of Misiryeong and Daegwallyeong, happens the orographic precipitation in spatial analysis, but the orographic effects didn't occur for the whole Gangwon areas. However, to achieve more accurate results, the expansion of observatories per elevation and AWS data are demanded.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.11 no.3
• /
• pp.219-230
• /
• 2015

It is difficult to make plans about the production schedule and volume of seasonal products due to the huge uncertainty in the prediction of their demands, which is why the amounts of carryover seasonal products increase after the peak season. Traditional models fail to meet the important requirements of production and stock plans related to the enhanced efficiency of logistics system due to the reduced value of carryover products by the disposal based on large discounts and deterioration, which poses considerable difficulties with actual problem solving. This study examined the stages of product storage from the specialized factory warehouses during a low season through the stores and the warehouses of local distribution centers during a high season to stock disposal and carryover product warehouses after a high season. The study developed a model for logistics rationalization plans to minimize carryover products by advance selling new products by subscription during a low season in anticipation of high season demands, increasing the accuracy of demands prediction, and making stable production plans, as well as demonstrated its excellence through numerical analysis.

• Asian Journal of Atmospheric Environment
• /
• v.6 no.1
• /
• pp.23-32
• /
• 2012

The ionic composition of $PM_{2.5}$ samples was investigated by their datasets of cationic ($Na^+$, $NH_4^+$, $K^+$, $Mg^{2+}$, and $Ca^{2+}$) and anionic components ($Cl^-$, $NO_3^-$, and $SO_4^{2-}$) along with relevant environmental parameters collected from an urban monitoring site in Korea at hourly intervals in 2010. The mean (and SD) annual concentration of $PM_{2.5}$ was computed as 25.3 ${\mu}g\;m^{-3}$ with the wintertime maximum. In addition, sum concentrations (neq $m^{-3}$) of five cationic species (291) were slightly lower than 3 anionic species (308). Most cations exhibited the highest seasonal values in spring, while anions showed more diversified seasonal patterns. According to PCA, five major source categories were apparent with the relative dominance of secondary inorganic aerosols (SIA). The results of our study suggest consistently that the distribution of ionic constituents in an urban area is affected by the combined effects of both natural and anthropogenic processes.

• Journal of the korean society of oceanography
• /
• v.35 no.4
• /
• pp.161-169
• /
• 2000

A seasonal circulation in the East China Sea and the Yellow Sea and its possible cause have been studied with CSK data during 1965-1989. Water mass distributions are clear in winter, but not in summer because the upper layer waters are quite influenced by atmosphere. To solve the problem, a water mass analysis by mixing ratio is used for the lower layer waters. The results show that the distribution of Tsushima Warm Current Water expands to the Yellow Sea in winter and retreats to the East China Sea in summer. It means that there is a very slow seasonal circulation between the East China Sea and the Yellow Sea: Tsushima Warm Current Water flows into the Yellow Sea in winter and coastal water flows out of the Yellow Sea in summer. By the circulation, the front between Tsushima Warm Current Water and coastal water moves toward the shelf break in summer so that the flow is faster in the deeper region. The process eventually makes the transport in the Korea Strait increase. The Kuroshio does not seem to influence the process. A possible mechanism of the process is the seasonal change of sea surface slope due to different local effects of surface heating and diluting between the East China Sea and the Yellow Sea.

• Journal of Korean Society on Water Environment
• /
• v.27 no.4
• /
• pp.433-437
• /
• 2011

The study is conducted to evaluate loading of organic matter as seasonal changes during non-storm period into Lake Paldang which is used to a major drinking water source. Samples were taken in Lake Paldang intake during non-storm period and were analyzed loading of organic matter. From the results of the survey, improving of the water quality showed remarkable tendency depending on the changing periods from summer to fall and from fall to winter. Dilution effect from the increase of base run-off caused by the concentrated rainfall in rainy season, the characteristics of Korea's climate seems to have to be the reason. On the other hand, deteriorating of the water quality showed tendency depending on the changing periods from winter to spring and from spring to summer. Increase of Cyanobacteria etc. is explained by seasonal effects which are a small amount of the rainfall in winter and spring and gradational increase of water temperature.

• Environmental and Resource Economics Review
• /
• v.31 no.3
• /
• pp.343-365
• /
• 2022

This paper tries to identify the effect of reducing PM2.5 concentration of the First Seasonal Management Policy implemented by Korean government by using statistical method. In particular, this paper tests the hypothesis that this policy effect may differ by region (west-coast, south-coast, and east-coast). To this end, this paper analyzed only pure policy effects by removing temporal abnormalities such as COVID-19, warm winter temperature during the policy implementation period (December 2019 to March 2020) by using the difference-in-difference method (DID). As a result of the analysis, this policy had the effect of reducing PM2.5, but the effect is not homogenous by region. In particular, PM2.5 reducing effect is the largest in west-coast region and south-coast region folllows, but its effect is not statistically significant in the east-cost region. In conclusion, this paper drew implications that the current Seasonal mamangement policy which is implemented regardless of the regional difference needs to be changed.