• The Journal of Information Systems
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• v.24 no.3
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• pp.133-154
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• 2015

Purpose This study re-analyzes Jung 2012's data using the time interval based analysis to examine if the process of idea generation is in good currency throughout the ideation sessions. In this way, the relationship between extraversion-introversion personality trait and ideation performance in the context of computer-mediated idea generation can be better understood. Design/methodology/approach A $2{\times}4$ factorial design was used, crossing personality differences (extraversion and introversion) with the degree of stimuli (0, 20, 40, and 80 high-quality ideas). Participants were randomly assigned to one of eight treatment conditions. The group simulator is used to measure individual level performance. The number of unique ideas generated by individuals and the exact time stamp when each idea was submitted were analyzed to compare performances. Findings The results show that introverts' performances significantly drops after about the middle stage of the ideation session, whereas extraverts do not seem to feel time constraints throughout the ideation session, resulting in superior divergent thinking, which is a major key to understand creative productivity in the problem-solving process. Since extraverts tend to yield a larger pool of ideas, another interpretation is that group composition with extraverts compared with introverts may create a logically larger group, which is important to improve the performance of idea generation group.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.1
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• pp.40-48
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• 2001

The vertical distributions of temperature, salinity, dissolved oxygen, nutrients, chlorophyll, and primary production were investigated within the top 200m water depth in the south Pacific Ocean in February,2000. The study area ($24^{\circ}-41^{\circ}S,\;81^{\circ}-168^{\circ}W$) can be hydrologically divided into two regions. Upwelling was actively occurring in the eastern region of the $110^{\circ}S$ line, meanwhile it was not active in the western region. Accordingly, chemical properties in the surface waters were different between the two regions; nitrate+nitrite and phosphate concentrations were much higher in the eastern region than in the western region due to the active upwelling, but silicate concentration was higher in the western region. Among the nutrients, the major element influencing primary production was also different between the two regions; silicon would be a major element influencing primary production in the eastern region, but nitrogen may act as a major element for primary production in the western region. Primary production showed similar values in the two regions in spite of the large differences of nutrient concentrations in the surface waters, but the total chlorophyll integrated within the 200 m water depth was almost twice as much as in the western region than that in the eastern legion.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.687-702
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• 2012

The objective of this study was to determine crop rotation effects on potato yield, soil chemical and microbiological properties from a short-term field experiment from 2010 to 2011 in Jeju Island, Korea. Potato cropping systems included continuous and rotation sequences of soybean (Glycine max(L.) Merr.), barley (Hordeum vulgare var. hexastichon), rapeseed (Brassica napus L.) and broccoli (Brassica oleracea var. italica). Crop rotations increased the yields of potato from 31% to 52% compared with continuous potato. Marketable yield of potato was highest under soybean plus rapeseed rotation by $20.97MT\;ha^{-1}$ and lowest under continuous cropping by $11.95MT\;ha^{-1}$. The incidence and severity of scab disease was significantly lower in tubers from crop rotation with soybean plus barley. Differences in marketable tuber yields among rotations were associated with potato scab disease. Especially, incidence and severity of potato scab were strongly correlated with soil pH, exchangeable calcium, and bacteria population of the soil. Crop rotations significantly increased soil pH, available phosphate, exchangeable K and Ca, especially in crop rotations with soybean plus barley or rapeseed. Soil microbial biomass C of crop rotations with soybean plus barley or rapeseed, was also significantly higher compared with monoculture. In conclusion, crop rotation may decrease the incidence of soil-born pathogen by increasing soil chemical properties and soil microbial biomass. Overall, potato crop productivity was generally maintained in rotations that contained soybean plus barley or rapeseed but declined under continuous cropping system.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.4
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• pp.257-262
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• 2007

The objective of this research was to develop a high yielding, early and medium-late flowering new hairy vetch(Vicia villosa Roth) varieties derived from an accession in Korea. Most vigorous early and medium-late flowering hairy vetch lines were selected and crossed by open pollination and their seeds were bulked and plants were reselected at Seongju in the Keongbuk and at Sacheon in the Keongnam. A performance trial was conducted to evaluate agronomic characteristics, forage quality and dry matter(DM) yield of new hairy vetch early-maturing 'Cold green' and medium-late maturing variety 'Cheong pa' at Seongju and Sacheon. 'Cold green' and 'Cheong pa' are hair but 'Haymaker plus' and 'Latigo' are nearly hairless. 'Cold green' has purple flowers while 'Cheong pa' has violet. The cold tolerance of 'Cold green,' 'Cheong pa' and 'Latigo' was higher than 'Haymaker plus' at Seong-ju, Keongbuk province, in inland region but there were a little differences at Sacheon, Keongnam province in southern coast region. Fifty percent-flowering dates of 'Cold green' and 'Haymaker plus' had earlier than others and 'Cheong pa' was earlier than 'Latigo'. The DM yield of 'Cold green' was higher than that of others, but 'Cheong pa' and 'Haymaker plus' had higher than 'Latigo' at Seong-ju(P<0.05). In Sacheon, The DM yield of 'Cold green' and 'Haymaker plus' was higher than others and 'Cheong pa' had higher than 'Latigo'.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.5
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• pp.47-62
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• 2020

Rice paddy accounts for approximately 52.5% of all farmlands in South Korea, and it is closely related to the water environment. Climate change is expected to affect not only agricultural productivity also the water and the nutrient circulation. Therefore this study was aimed to evaluate changes of nitrogen load from rice paddy considering climate change scenario uncertainty. APEX-Paddy model which reflect rice paddy environment by modifying APEX (Agricultural Policy and Environmental eXtender) model was used. Using the AIMS (APCC Integrated Modeling Solution) offered by the APEC Climate Center, bias correction was conducted for 9 GCMs using non-parametric quantile mapping. Bias corrected climate change scenarios were applied to the APEX-Paddy model. The changes and uncertainty in runoff and nitrogen load were evaluated using multi-model ensemble. Paddy runoff showed a change of 23.1% for RCP4.5 scenario and 45.5% for RCP8.5 scenario compared the 2085s (2071 to 2100) against the base period (1976 to 2005). The nitrogen load was found to be increased as 43.9% for RCP4.5 scenario and 76.0% for RCP8.5 scenario. The uncertainty analysis showed that the annual standard deviation of nitrogen loads increased in the future, and the maximum entropy indicated an increasing tendency. And Duncan's analysis showed significant differences among GCMs as the future progressed. The result of this study seems to be used as a basis for mid- and long-term policies for water resources and water system environment considering climate change.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.1
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• pp.11-15
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• 2005

This experiment was conducted to investigate the changes of growth and maturity and to clarify the function of supernodulating characters, excessive nodules and high biological nitrogen fixation rate (BNF), on maturity in response to different planting time in supernodulating soybean mutants. Two supernodulating soybean mutants, Sakukei4 and SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2, were planted on May 24 and June 15, 2004. The degrees of the shortening of growth days by the planting time delay were 18 to 22 days in four cultivar, and there were no significant differences among the cultivars. However, four cultivars showed the different maturity properties. Sakukei4, mutated from Enrei, showed later maturity than that of Enrei, and 882-2, mutated from Shinpaldalkong2, showed earlier maturity than that of Shinpaldalkong2. The plant and nodule dry weights at R6 stage of Sakukei4 showed the smallest decrement and those of SS2-2 was showed the largest decrement by the delay of planting time. The photosynthetic rates of Sakukei4 during the late reproductive growth period were slowly decreased, however those of SS2-2 were steeply decreased in two planting time treatments. Overall, the growth of Sakukei4 was decreased slowly, however the growth of SS2-2 was decreased sharply according to the delay of planting time. The percentage of seed yield of Sakukei4 in June planting plot compared with May planting plot at R8 stage was $92\%$, which was the lowest decreasing rate of yield among the cultivars, and in the case of SS2-2, it was in $76\%$, the highest one. These results indicated that the responses of supernodulating mutants by the delay of planting time were very similar to the wild types. This means supernodulating characters in supernodulating soybean mutants might not affect to the maturity property. Additionally, the maturity property could be considered as an important characteristics to decide or to select on the developments of supernodulating soybean mutants, which have a low productivity by an excessive nodules, especially.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.428-434
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• 2008

The objective of this study is to investigate the effect of the level of $CO_2$ (370 and $650{\mu}mol\;mol^{-1}$) and temperature (ambient and ambient+$5^{\circ}C$) on tomato growth and fruit characteristics as affected by the application rate of N-fertilizer (68 and $204\;N\;kg\;ha^{-1}$), for the purpose of evaluating the influence of elevated $CO_2$ and temperature on tomato crop. The elevated atmospheric $CO_2$ and temperature increased the plant height and stem diameter for tomato crop, while the differences among the nitrogen(N) application rates were not significantly different. Under the elevated $CO_2$, temperature, and a higher N application rate, the biomass of aerial part increased. The fruit yield showed the same result as the biomass except for the elevated temperature. The elevated temperature made the size of fruit move toward the small, but the elevated $CO_2$ and the application of N-fertilizer were vice versa. The sugar content and pH of fruit juice were affected by nitrogen application rate, but not by the elevated $CO_2$ and temperature. These results showed that both the elevated $CO_2$ and temperature stimulated the vegetative growth of aerial parts for tomato, but each effects on the yield of fruit showed an opposite result between the elevated temperature and $CO_2$. In conclusion, the elevated $CO_2$ increased tomato yield and the ratio of large size of fruit, but the elevated temperature did not. Therefore, to secure the productivity of tomato as nowadays in future environment, it will need to develop new breeder as high temperature-tolerable tomato species or new type of cropping systems.

• Korean Journal of Ecology and Environment
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• v.43 no.4
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• pp.492-502
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• 2010

The study objects were to analyze long-term and seasonal variations of nutrients (N, P), suspended solids, N:P ratios, algal chlorophyll, and trophic state along with general water quality parameters in four sampling sites including two intake tower sites supplying drinking water in Daechung Reservoir. For the analysis, we used water quality long-term data sampled during 1998~2007 by the Ministry of Environment, Korea. Interannual and seasonal trends in inflow and discharge near the intake tower facilities over the ten years were directly influenced by rainfall pattern. The distinct difference between wet year (2003) and dry year (2001) produced marked differences in water temperature, pH, dissolved oxygen, organic matter contents, nutrients, and these variables influenced algal biomass and trophic state. Values of TP varied depending on the year and locations sampled, but monthly mean TP always peaked during July~August when river inflow and precipitation were maxima. In contrast, TN varied little compared to TP, indicating lower influence by seasonal flow compared to phosphorus. The number of E. coli were highest in Site 2 (Chudong intake tower) and varied largely, whereas at other sites, the numbers were low and low variations. Contents of chlorophyll-${\alpha}$ (CHL), as an estimation of primary productivity, varied largely depending on the year and season. The maximum of CHL occurred at Muneu intake tower (S4) during 2006 when the precipitation and inflow were lowest. In contrast, another CHL peak was observed in Site 2 (Chudong intake tower) in 2006 when one of the largest typoons (Ewinia) occurred and river runoff were maximum. So the CHL maxima were associated with both wet year (high flow, high nutrient supply) and dry year (low flow, nutrient supply by littoral zone). Such conditions influenced trophic states, based on Trophic State Index of nutrients and CHL. Based on all analyses, we can provide some clues for management and protection strategies of two intake tower sites.

• Clean Technology
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• v.10 no.2
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• pp.101-109
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• 2004

PSA and VSA processes have been used broadly to produce oxygen from ambient air in midium- or small-sized plants. PSA and VSA processes are the separation methods which use difference of amount adsorbed as pressure is changed periodically, but they have the differences in pressurization and regeneration. In this study, the performance of 6-step PSA process was compared with that of 5-step VSA process with respect to purity and recovery. In addition, the effects of each step (pressurization step, adsorption step, and pressure equalization step) on purity and recovery were investigated. As a result, the VSA process using zeolite 10X showed better performance than the zeolite 5A PSA and zeolite 13X VSA process in comparison with purity, recovery and productivity. And it was enough to apply the vacuum pressure of 200 torr for the VSA, which produced over 90% oxygen with 70% recovery.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.102-112
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• 2003

The objective of this study was to investigate the effects of food waste and probiotics supplementation on productive performance and egg composition of laying hens. Total 120 layers (Brown Tetran) 22 weeks old were divided into five groups with 4 replicates for each treatments and raised in battery cage. The experimental design was completely randomized. The egg Production rate was significantly increased in layer supplemented with 0%, 0.5%, 1.0% and 1.5% of probiotic supplemented diets compared to control (P<0.05). At feeding with food waste and probiotic supplementation had no effect on the egg shell strength (P>0.05). Haugh unit of the eggs was significantly increased in layers fed with 1.5% of probiotic supplemented diet (P<0.05). The different levels of inclusion of the food waste and probiotic supplementation had not effect on egg shell color, blood spot and albumen index of the eggs (P<0.05). There were not significant differences in over all acceptability, juiciness, texture and color of the eggs from layer fed with different levels of wood waste and probiotic supplementation. The appearance and flavor significantly deteriorated in eggs from layers fed with probiotic diets compared to control (P<0.05).