• The Journal of Society for e-Business Studies
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• v.24 no.1
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• pp.1-16
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• 2019

Recently, since responding to meteorological changes depending on increasing greenhouse gas and electricity demand, the importance prediction of photovoltaic power (PV) is rapidly increasing. In particular, the prediction of PV power generation may help to determine a reasonable price of electricity, and solve the problem addressed such as a system stability and electricity production balance. However, since the dynamic changes of meteorological values such as solar radiation, cloudiness, and temperature, and seasonal changes, the accurate long-term PV power prediction is significantly challenging. Therefore, in this paper, we propose PV power prediction model based on deep learning that can be improved the PV power prediction performance by learning to use meteorological and seasonal information. We evaluate the performances using the proposed model compared to seasonal ARIMA (S-ARIMA) model, which is one of the typical time series methods, and ANN model, which is one hidden layer. As the experiment results using real-world dataset, the proposed model shows the best performance. It means that the proposed model shows positive impact on improving the PV power forecast performance.

• The Korean Journal of Ecology
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• v.14 no.4
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• pp.415-433
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• 1991

Seasonal variation in size and number of floral structures was examined in two massachusetts populations of chelidonium major, a self-compatible herb. All floral charcters except for anther number per flower declind significantly during a 3 week period. However, temporal patterns were not identical among characters or between popolations. The result indicate that floral characters varied in conjunction with flower diameter,but that the pattern of changes in floral characters in response to environments may not be easy to predict. Principal components analysis was conducted to environments may not be easy to predict. principal compenents analysis was conducted tl identify the functional relationship among floral male function, and female function, respectively, perhaps reflecting the functional distinction of floral characters. Based on this pattern, the relative allocation to sexual structures within flowers was examined: male allocation was relatively greater than female allocation eary or in the middle of flowering season, depending upon populations. Temporalvariation in relative allocation within flowers was not independent of seed tield components:; different combinations of the size and number of floral characters were correlated with different seed yield components, for example, either seed size or number per fruit, during a season. in particular, allocations to attractive and male structures were highly correlated with mean seed weight only earlier in the season. These result provide some evidence that flowering phenolgy is an important comportant to be considered in the study of sexual allocation.

• Bulletin of the Korean Space Science Society
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• 2010.04a
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• pp.34.2-34.2
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• 2010

We built 7 potential extra-terrestrial planets including the full 3D Earth model with various surface types and 6 planet models, each with uniform surface characteristics. The surface types include ice, tundra, forest, grass, ground and ocean. We then imported these 7 planets into integrated ray tracing(IRT) model to compute their disk averaged spectra and to understand the spectral behavior depending on the geometrical view, illumination phase and seasonal change. The IRT computation show that the 6 planets with uniform surfaces exhibit clear spectral differences from that of the Earth. We then built a phase and seasonal DAS database for the 6 uniform surface planets and used them for parametric spectral decomposition technique to derive the Earth DAS. This computation resulted in the first potential solution to the surface type ratio of the Earth compared to the measured earth surface type ratio. The computational details and the implications are discussed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.214-215
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• 2014

Recently, Russia decided to export an annual 7.5 million tons of natural gas to Korea over 30 years from 2015, as also deal with China, planed to build a pipeline connecting Siberia to Shandong Peninsula about 4000km. Risk management is required depending on the project in extreme cold weather, because it is concerned about the behavior of the seasonal changes in soil temperature and the strain of pipe according to the long-distance pipeline construction. The plan of data management shall be prepared in parallel for a sophisticated risk management, because a data is massive scale and it is generated/accumulated in real time. Therefore, this research is aimed to classify a data items in engineering stage of pipeline by previous studies for managing a generated data depending on the detail works in extreme cold weather. We expect to be provided the foundation of an efficient classification system of a generated data from the pipeline project life cycle.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.512-518
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• 2008

This study were to evaluate trophic conditions, N : P ratios, and empirical relations of chlorophyll (CHL) systematically using TN, TP, and CHL values in agricultural reservoirs and drinking water supplying dams. During the study, nutrients and CHL varied depending on seasonal conditions and types of the reservoirs, but most reservoirs were diagnozed as eutrophic to hypertrophic. Mass ratios of TN : TP averaged 93.1 (range: $0.68{\sim}1342$) and about 96.6 % of the total observations (n=516) was > 17 in the N : P ratios. This result suggests that P was a potential factor limiting algal growth in the entire reservoir. Thus, TN : TP ratios were a function of phosphorus rather than nitrogen. Regression analysis of log-transformed N : P ratios against TP in DWDRs and ARs showed that ratios were linearly declined with an increase of TP ($R^2$>0.66; p<0.001). Seasonal mean CHL was minimum ($4.3{\mu}g\;L^{-1}$, range: $0.1{\sim}39.7{\mu}g\;L^{-1}$) in premonsoon, and was similar between the monsoon and postmonsoon. In contrast, one of the tremendous features was that values of CHL was greater in the ARs than DWDRs. Thus, the spatial and temporal patterns in CHL were similar to those of TP but not TN. Empirical models of CHL-TP showed that CHL variation could explain average 15.3% and 11.3% in DWDRs and ARs, respectively. Seasonal analysis of empirical models showed that CHL-TP relations were stronger in postmonsoon than those of premonsoon and monsoon.

• Ocean and Polar Research
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• v.35 no.2
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• pp.147-155
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• 2013

The purpose of this study is to investigate seasonal difference in linear trends in satellite-derived chlorophyll-a concentration (Chl-a) and their related environmental changes in the South Sea of Korea (SSK) and East China Sea (ECS) for recent 15 years (Jan. 1998~Dec. 2012) by analyzing climatological data of Chl-a, Rrs(555), sea surface wind (SSW) and nutrient. A linear trend analysis of Chl-a data reveals that, during recent 15 years, the spring bloom was enhanced in most of the ECS, while summer and fall blooms were weakened. The increased spring (Mar. - May) Chl-a was associated with strengthened winter (Dec. - Feb.) wind that probably provided more nutrient into the upper ocean from the deep. The causes of decreased summer (Jun. - Aug.) Chl-a in the northern ECS were uncertain, but seemed to be related with the nutrient limitation. Recently (after 2006), low-salinity Changjiang diluted water in the south of Jeju and the SSK had lower phosphate that caused increase in N/P ratio with Chl-a decrease. The decreased fall (Sep. - Nov.) Chl-a was associated with weakened wind that tends to entrain less nutrient into the upper ocean from the deep. This study suggests that phytoplankton in the ECS differently changes in response to environmental changes depending on season and region.

• Journal of the Korean Wood Science and Technology
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• v.51 no.4
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• pp.295-308
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• 2023

This study applied a real-time IoT (Internet of Things) environmental monitoring system to wooden cultural heritages (WCHs) located in suburbs and forests in Korea. It automated the graphs of seasonal Temperature (T) and relative humidity (RH) changes inside the heritage structures and seasonal Performance Index (PI) values. While utilizing line graphs of the existing T and RH change trends and a bar graph expressing the PI values, this study examined the current status of the conservation environment inside the WCHs throughout the year and its diagnosis. Consequently, at higher latitudes, the organic cultural heritage repeatedly experienced large T fluctuations, and the risk of physical and chemical degradation of the materials was greater. However, the RH showed significant seasonal differences, even within the same latitude, indicating that the impact of latitude was not significant. Therefore, the staff in charge must manage RH by considering the surrounding environmental conditions and adjusting the internal environment of the structures. The PI values for the year-round T and RH inside the heritages were confirmed to only be a maximum of approximately 60% of the environmental suitability for conservation throughout the year, depending on the season. The relationship between the germination and growth potential period of xerophilic fungi and the monthly internal temperature and humidity in five heritages located at different latitudes was analyzed. As a result, we could thus determine that four particular months of the year (June-September) represent the periods with the highest risk of damage from xerophilic fungi in the country, regardless of latitude.

• Journal of Environmental Impact Assessment
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• v.21 no.2
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• pp.279-287
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• 2012

Phytoncide, which is emitted from plant against the insect species and bacterium, has been known as a health builder for human. Monoterpenes are major components of phytoncide. This study was conducted to investigate the distribution characteristics of phytoncide(monoterpene) depending on main species of tree, season, and meteorological factors in the 5 recreation forests, Chungbuk area. From the result of the study. it was shown that the annual concentrations of monoterpene are ranged in 236.0pptv - 698.3pptv depending on main species of tree. The variation of seasonal concentration was summer > spring > fall. The monoterpene concentration of coniferous forest was founded to be higher than broad leaved forest. In general, concentration of major components is ${\alpha}$-pinene > ${\beta}$-pinene > camphene > d-limonene. The concentration of terpene was founded to be greatly influenced by the meteological factors such as insolation and temperature.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.104-116
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• 2019

Background: The composition of wild bird populations in temperate zones greatly varies depending on phenological changes rather than other environmental factors. Particularly, wild birds appearing in wetlands fluctuate greatly due to the crossover of species arriving for breeding during the summer and for wintering. Therefore, to understand the changes to species composition related to phenology, we conducted this basic analysis of populations to further the cause of the protection of wetland-dependent wild birds. Methods: It is wrong to simply divide a wild bird population investigation into seasons. This study identifies species composition and indicator species that change along with seasons. Wetlands to be surveyed are protected by natural monuments and wetland inventory and are in a state close to nature. In order to identify as many species as possible in wetlands, a survey was conducted in both shallow and deep wetlands. The water depth varied in these areas, ranging from 0.2 to 2.0 m, allowing for both dabbling and diving ducks to inhabit the area. Surveys were conducted using line-transect and distance sampling methods and were conducted at intervals of 2 weeks. The survey was conducted under the following three categories: the eco-tone and emergent zone, the submergent zone, and the water surface. The survey was conducted along a wetland boundary by observing wild birds. A PC-ord program was used for clustering, and the SAS program was used to analyze the changes in species composition. The data strongly indicates that day length is the main factor for seasonal migration periods, despite the fact that climate change and increasing temperatures are often discussed. Results and conclusions: The indicator species for determining seasons include migrant birds such as Ardea cinerea, Alcedo atthis, Anas penelope, and Poiceps ruficollis, as well as resident birds such as Streptopelia orientalis and Emberiza elegans. Importantly, increases in local individual counts of these species may also serve as indicators. The survey results of seasonal fluctuations in temperate zones shows that spring (April to June), summer (July to September), autumn (October), and winter (November to March) are clearly distinguishable, even though spring and summer seasons tend to overlap, leading to the conclusion that additional research could more clearly identify fluctuation patterns in species composition and abundance in the study area.

• Food Science and Preservation
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• v.22 no.3
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• pp.303-313
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• 2015

This study investigates the physicochemical, microbiological and sensory characteristics of seasonal salted-Kimchi cabbages to provide basic data on its uniform quality. Generally, seasonal salted-Kimchi samples had different pH values at initial storage periods, but there was no difference in pH between the seasonal samples when stored for longer periods. The samples from the fall and winter seasons were relatively low in acid and high in solid soluble content compared to samples from other seasons. Salted-Kimchi cabbages in the summer showed the highest microbiological number compared to samples from other seasons. In the sensory evaluation, there were differences in the appearance, aroma, and taste, depending on seasonal samples at different storage periods. The correlation coefficient between the quality characteristics in the seasonal samples showed a positive or negative correlation between the quality characteristics at 1% significant level. In the principal component analysis, F1 and F2 were shown the 51.81% and 14.23% of the total variance (66.21%), respectively. In the PCA pattern of seasonal salted-Kimchi cabbages during storage periods, winter samples were distributed on the top of F2, spring samples were in the middle of F2, while the rest of the samples were distributed on the bottom of F2. According to increasing storage periods, initial storage samples were distributed at the left of F1, while other samples were located at the right of F2.