• Journal of Korean Society of Forest Science
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• v.83 no.1
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• pp.12-19
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• 1994

Studies were made to find out the mycelial growth and rotting characteristics of 91 Lentinus edodes isolates collected or hybridized in Korea and abroad, and their adaptability to bag-culture. The results are as follows. 1. There were little differences in mycelial growth at PDA and oak (Quercus mongolica) sawdust-based medium, and rotting among high-, mid- and low temperature types of L. edodes isolates. But, the fruit yield of high-temperature type was much higher than those of the other two types. The fruit yields of the isolates in the same strain group were apparently different. 2. From the sawdust-based culture of 91 isolates, FRI 221, FRI 208 and FRI 169 were selected as excellent strains in yield and Quality, showing fruiting of 157g, 152g and 119g per 1kg-medium, respectively. 3. Attempts to culture in various media with different substrates resulted in almost same fruit yields, and the yield was proportional to medium weights as 2.5kg-medium showed 2.5 times more yield than 1kg-medium. Fruit yields were different according to incubation periods and the period of little more than 100days was best. 4. When the correlation analyses among mycelial growth, rotting ability, yield and fruit-shape normality were made with the 91 isolates, mycelial growth at sawdust-based medium showed highly positive correlation with that at PDA, while fruit yield was negatively correlated with mycelial growth in PDA and sawdust-based medium.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.185-194
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• 1995

The prevention of excessive use of nitrogen fertilizer get an attention in Korea not only for minimizing $NO_3^-$ contamination of groundwater but also for establishment of environmental friendly sustainable agriculture. In order to find out the dynamics of $NO_3^-$ in barley rhizosphere and its suitability for nitrogen fertilization strategies and for environmental control, the accumulation of $NO_3^-$ in 3 layer, 0~30cm, 30~60cm, 60~90cm of soil profile has been detected in winter barley pro-duction system. It showed the recommended N fertilization rate for winter barley cause the $NO_3^-$ contamination of groundwater through $NO_3^-$ leaching during winter. The $NO_3^-$ content of 0~90cm soil depth have directly reflected the amount of basal N fertilization in the early spring, but not 0~30cm and 0~60cm soil depth. The contents of $NO_3^-$ measured to 0~30cm, 0~60cm soil depth were not significanly correlated with yield but the contents of $NO_3^-$ measured to 90cm soil depth was highly correlated with yield. Nitrogen fertilizer requirement could be estimated accurately by soil test and it provides field specific N rate recommendation for spring N application to winter barley. It was concluded that $N_{min}$ method could be applied to korean climatic and soil condition for optimal fertilizer application rate.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.683-693
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• 2017

Transport biofuels have been recognized as a promising means to resolve the following issues like global warming, oil depletion and environmental pollutions. Among various biofuels, biodiesel has several advantages such as less emission of air pollutants and higher cetane values compared to diesel oil. Demand for biodiesel in Korea is increasing that leads to higher dependence on the imported feedstocks. Therefore, it is important to utilize the waste materials collected domestically for biodiesel production. Food waste oil collected in waste treatment facility has not been used for biodiesel production due to high free fatty contents in the oil. In this work, biodiesel conversion of food waste oil by Amberlyst 15 was studied. Synthetic and actual food waste oils have been used in the study. First, the effects of the major operating parameters including reaction temperature, methanol to oil molar ratio and catalyst loading on the conversion rates and yields were determined with synthetic waste oil. Kinetic modelling work was also done to determine the activation energy of the reaction. From the work, optimization reaction conditions were determined to be 383K, 1: 26.1 for methanol molar ratio to oil, 10 wt.% for catalyst loading and 360 min for reaction time. Activation energy of the reaction is determined to be 29.75 kJ/mol, lower than those reported in the previous works. So the solid catalyst, Amberlyst 15, was more efficient for esterification than the solid catalysts employed in the other works. Agitation rates have the negligible effects on the conversion rates and yields. With the identified optimization conditions, conversion of the actual food waste oil was also carried out. The esterification yield of actual food waste oil in 60 min was 13% lower than that of synthetic waste oil but the final yields in 240 min were similar each other, 98.12% for synthetic oil and 97.62% for actual waste oil.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.781-796
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• 2015

This study was carried out to investigate the effect of no-tillage and split irrigation on the growth of pepper plant under green house condition in Jeonnam province. Moisture content of soil at whole quantity irrigation in tillage was increased rapidly regardless of soil depth for initial irrigation and then was decreased continuously until next irrigation. Deviation of moisture content in soil was decreased with increasing depth of soil. Moisture contents of top soil and subsoil (20 cm) at whole quantity irrigation in no-tillage were increased with sunrise, and then decreased with sunset. Moisture contents of top soil in tillage, and top soil and subsoil (20 cm) in no-tillage at half quantity irrigation indicated a cyclic diurnal variation by evapotranspiration. Salinity of soil was increased after initial irrigation and then was decreased continuously until next irrigation. With increasing depth of soil, increases of salinity in soil was delayed. Salinity of top soil in no-tillage was increased between AM 11:00 and AM 12:00, and then showed the highest level between PM 2:00 and PM 6:00 on a cyclic diurnal variation by evapotranspiration. Salinity of subsoil (30 cm) in no-tillage was not measured a cyclic diurnal variation. Moisture content and salinity of soil was positive correlation regardless of tillage and no-tillage cultivation. Growth of pepper in no-tillage cultivation was higher than that in tillage cultivation. Main branch Length and stem diameter of half quantity irrigation plot was higher than that of whole quantity irrigation plot regardless of tillage and no-tillage cultivation. After harvesting, the number of pepper fruits of half quantity irrigation plot was increased remarkably by 49% and 47%, in tillage and no-tillage cultivation, respectively. Pepper yield of no-tillage cultivation plot was higher by 8% than that of tillage cultivation plot. Pepper yield of half quantity irrigation plot was increased remarkably by 36% and 39%, in tillage and no-tillage cultivation, respectively.

• Journal of Intelligence and Information Systems
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• v.25 no.4
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• pp.1-33
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• 2019

The small and medium sized enterprises (hereinafter SMEs) are already at a competitive disadvantaged when compared to large companies with more abundant resources. Manufacturing SMEs not only need a lot of information needed for new product development for sustainable growth and survival, but also seek networking to overcome the limitations of resources, but they are faced with limitations due to their size limitations. In a new era in which connectivity increases the complexity and uncertainty of the business environment, SMEs are increasingly urged to find information and solve networking problems. In order to solve these problems, the government funded research institutes plays an important role and duty to solve the information asymmetry problem of SMEs. The purpose of this study is to identify the differentiating characteristics of SMEs that utilize the public information support infrastructure provided by SMEs to enhance the innovation capacity of SMEs, and how they contribute to corporate performance. We argue that we need an infrastructure for providing information support to SMEs as part of this effort to strengthen of the role of government funded institutions; in this study, we specifically identify the target of such a policy and furthermore empirically demonstrate the effects of such policy-based efforts. Our goal is to help establish the strategies for building the information supporting infrastructure. To achieve this purpose, we first classified the characteristics of SMEs that have been found to utilize the information supporting infrastructure provided by government funded institutions. This allows us to verify whether selection bias appears in the analyzed group, which helps us clarify the interpretative limits of our study results. Next, we performed mediator and moderator effect analysis for multiple variables to analyze the process through which the use of information supporting infrastructure led to an improvement in external networking capabilities and resulted in enhancing product competitiveness. This analysis helps identify the key factors we should focus on when offering indirect support to SMEs through the information supporting infrastructure, which in turn helps us more efficiently manage research related to SME supporting policies implemented by government funded institutions. The results of this study showed the following. First, SMEs that used the information supporting infrastructure were found to have a significant difference in size in comparison to domestic R&D SMEs, but on the other hand, there was no significant difference in the cluster analysis that considered various variables. Based on these findings, we confirmed that SMEs that use the information supporting infrastructure are superior in size, and had a relatively higher distribution of companies that transact to a greater degree with large companies, when compared to the SMEs composing the general group of SMEs. Also, we found that companies that already receive support from the information infrastructure have a high concentration of companies that need collaboration with government funded institution. Secondly, among the SMEs that use the information supporting infrastructure, we found that increasing external networking capabilities contributed to enhancing product competitiveness, and while this was no the effect of direct assistance, we also found that indirect contributions were made by increasing the open marketing capabilities: in other words, this was the result of an indirect-only mediator effect. Also, the number of times the company received additional support in this process through mentoring related to information utilization was found to have a mediated moderator effect on improving external networking capabilities and in turn strengthening product competitiveness. The results of this study provide several insights that will help establish policies. KISTI's information support infrastructure may lead to the conclusion that marketing is already well underway, but it intentionally supports groups that enable to achieve good performance. As a result, the government should provide clear priorities whether to support the companies in the underdevelopment or to aid better performance. Through our research, we have identified how public information infrastructure contributes to product competitiveness. Here, we can draw some policy implications. First, the public information support infrastructure should have the capability to enhance the ability to interact with or to find the expert that provides required information. Second, if the utilization of public information support (online) infrastructure is effective, it is not necessary to continuously provide informational mentoring, which is a parallel offline support. Rather, offline support such as mentoring should be used as an appropriate device for abnormal symptom monitoring. Third, it is required that SMEs should improve their ability to utilize, because the effect of enhancing networking capacity through public information support infrastructure and enhancing product competitiveness through such infrastructure appears in most types of companies rather than in specific SMEs.