• Electrical & Electronic Materials
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• v.9 no.9
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• pp.933-941
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• 1996

In this study, the Tx(Transmitting) and Rx(Receiving) band pass filter for personal communication services was constructed and designed using .lambda./4 TEM mode dielectric resonators. Band pass filter was composed of ceramics resonators which has been developed using ($Zr_{0.65}$,$Sn_{0.35}$) $Ti_{1.04}$ $O_{4.04}$ ceramic and Unloaded-Q ( $Q_{o}$) of .lambda./4 TEM mode dielectric resonator with inner hole size 0.9mm and external size 3mm using silver electrode is 354.5 at 1.95GHz. For the band pass filter design and construction, the design theory and simulation results of band pass filter using J-inverter theory have been studied. The parameters which are evaluated by design theory are practically applied to the filter construction and the simulation results are in agreement with the measured results after fine tunnings.s.s.s.s.s.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.561-571
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• 2020

Location information service using big data is continuously developing. In terms of navigation, the range of services from map API service to ship navigation information has been expanded, and system application information has been extended to SNS and blog search records for each location. Recently, it is being used as a new industry such as location-based search and advertisement, driverless cars, Internet of Things (IoT) and online to offline (O2O) services. In this study, we propose an information system that enables users to receive information about nearby stores more effectively by using big data when a user moves a specific route. In addition, we have designed this system so that local stores can use this system to effectively promote it at low cost. In particular, we analyzed web-based information in real time to improve the accuracy of information provided to users by complementing the data. Through this system, system users will be able to utilize the information more effectively. Also, from a system perspective, it can be used to create new services by integrating with various web services.

• Information Systems Review
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• v.24 no.3
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• pp.43-68
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• 2022

With the growing demand for online food delivery (OFD) services via Online to Offline (O2O) platforms, it is required for academic researchers to identify the success factors of OFD businesses. In line with this, this research examines the impact of the core service attributes of a restaurant (hygiene, interactivity, trust,and popularity) on business success in the OFD platform context from the perspective of information asymmetry. Furthermore, the moderating effects of hygiene factor between the core service attributes and the success of restaurants are evaluated. We utilize 1,146 restaurants registered on the largest OFD platform in Korea. The results of this study demonstrate that hygiene (certification), trust (franchise), popularity (favorite) factors have positive impacts on the success of OFD businesses. Moreover, we find that franchise restaurants with high response rates to customer reviews and inquiries achieve higher sales when they have hygiene certifications than those without the certification do. The key findings bear significant contributions to prior literature by empirically substantiating the pivotal role of service quality signals in fostering restaurant success on the OFD platforms. In addition, this study provides business implications for restaurants in O2O platform.

• Journal of Mushroom
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• v.6 no.2
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• pp.43-46
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• 2008

This study was carried out to investigate the utilization of platanus for Pleurotus ostreatus culture medium. The results are as follows ; The growth of mycelial was the highest in the mixture medium of platanus sawdust 90% with rice bran 10% as of 12.8cm after 30days culture. The mycelia density of most of media were high exception of mixture medium, platanus tree sawdust 60% with rice bran 40%. The total nitrogen, phosphate, and potassium contents in all mushroom media were tended to decrease after oyster mushroom growth. In platanus sawdust 90% with rice bran 10%, total nitrogen, potassium, calcium and magnesium content of fruit body were higher than other treatments, but phosphate content was the highest in Douglas-fir sawdust 80% with rice bran 20% treatment as of 0.92%. The mycelial culture period was ranged 26~37 days according to different media, the mushroom yield of culture medium with platanus tree sawdust 80% with rice bran 20% was increased 18% compare to control Douglas-fir sawdust 80% with rice bran 20%.

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.67-71
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• 2000

This study was conducted to determine the characteristics of continuous culture and soil texture and their effect on growth and yield of platycodon. The continuous cropping year was treated from 2-years old to 8-years old. The continuous cropping year was correlated with root weight $Y=17.246X+0.95(R^2=0.948^{{\ast}{\ast}{\ast}})$ and root disease incidence rate $Y=12.01X-5.74(R^2=0.946^{{\ast}{\ast}{\ast}})$. The T-N, $P_2O_5$ and MgO content of root were yearly decresed and those of injury roots were higher than those of normal roots. The 2-years old platycodon was treated different soil texture(Loamy sand, Sandy loam, Silt loam, Clay loam). The shoot weight 10.38g, root diameter 1.34cm, root height 16.8cm and root weight 5.46g at silt loam were higher than other soil texture.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.25-32
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• 2024

Frankliniella occidentalis and Thrips palmi are economically important pests of cucumber. The chemicals used to control them can be effective; however, they should not be used frequently on cucumbers that are consumed raw. Banker plants were selected to increase the control efficiency of Orius laevigatus, a natural enemy that can replace the chemicals. The hatching rate, emergence rate, nymph developmental period, survival rate, and reproductive capacity (fecundity and oviposition period) of O. laevigatus for four plants (moss rose, basil, broad bean, and cucumber) were investigated. The density of O. laevigatus on two selected banker plants was investigated in a cucumber greenhouse. The hatching rate of O. laevigatus eggs was highest at 92% in moss rose; however, there was no significant difference in survival rates between moss rose and basil. The fecundity and oviposition period of O. laevigatus were better in moss rose than in basil, with no significant difference between them. The flowering period of basil was longer than that of moss rose, from April to September. Therefore, basil has potential value as a banker plant for O. laevigatus and is expected to increase the biological control effect of O. laevigatus.

• Food Science and Preservation
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• v.15 no.1
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• pp.105-110
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• 2008

The antioxidant properties of bamboos sap isolated from Phyllostachys pubescens were investigated. This product scavenged intracellular reactive oxygen species (ROS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and prevented lipid peroxidation. The radical scavenging activity of bamboo sap protected the viability of peritoneal macrophage cells exposed to hydrogen peroxide $(H_2O_2)$, Furthermore, bamboo sap reduced apoptotic cell formation induced by $H_2O_2$ as demonstrated by decreases in the number of hypo-diploid cells am apoptotic cell body formation. These results indicate that bamboo sap has radical scavenging activity and ameliorates $H_2O_2$ induced cytotoxicity.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.163-169
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• 2015

The level of nitrous oxide ($N_2O$), a long-lived greenhouse gas, in atmosphere has increased mainly due to anthropogenic sources, especially application of nitrogen fertilizers. Quantifying $N_2O$ emission in the agricultural field is essential to develop national inventories of greenhouse gases (GHGs) emission. The objective of this study was to develop an emission factor to estimate the direct $N_2O$ emission from an agricultural field cultivated with the Chinese cabbage during autumn season in 2010-2012. Emission factor of $N_2O$ calculated over three years experiment using accumulated $N_2O$ emission, nitrogen fertilization rate, and background $N_2O$ emission was $0.0058{\pm}0.00254kg\;N_2O-N\;kg^{-1}\;N$. More extensive studies need to be conducted to develop $N_2O$ emission factors for other upland crops in the various regions of Korea because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices as well as crop species.

• Journal of the Korea Convergence Society
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• v.7 no.5
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• pp.161-167
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• 2016

Distribution channels are changing its industry paradigm from quantitative increase to qualitative improvement. In addition, it incorporates new characteristics and consumption tread of customers and the core value of service is developing focused around on online to offline (O2O) business model of omnichannel. In this respect, companies are integrating various distribution channels and in order to provide high content business service to customers, their interest in finding a new business strategy is increasing. Currently, most of the service being provided to customers are formed based on distribution structure centered around big companies and financial industry and the problems faced by small to medium and micro enterprises, which are expansion and improvement of channels, discovery of new distribution channels and finding O2O marketing strategy, can be said as very important task. Accordingly, this research purports to create added values which can serve as the driving force of growth of "creative economy" by improving distribution channels in which anyone who incorporates needs of smart consumers can enter into the smart commerce market and to further form sustainable win-win market that is strategic through business platforms for small to medium and micro enterprises therefrom.

• Informatization Policy
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• v.23 no.3
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• pp.26-42
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• 2016

Recently, with the rapid growth of the O2O market, Fintech combining the finance and ICT technology is drawing attention as innovation to lead "O2O of finance", along with Fintech-based payment, authentication, security technology and related services. For new technology industries such as Fintech, technical sources, related systems and regulations are important but previous studies on Fintech lack in-depth research about systems and technological trends of the domestic Fintech industry. Therefore, this study aims to analyze domestic Fintech trends and find the insights for the direction of technology and systems of the future domestic Fintech industry by comparing Kakao Pay and Samsung Pay, the two domestic representative mobile payment services. By conducting a complete enumeration survey about the tweets mentioning Fintech until June 2016, this study visualized topics extraction, sensitivity analysis and keyword analyses. According to the analysis results, it was found that various topics have been created in the technologies and systems between 2014 and 2016 and different keywords and reactions were extracted between topics of Samsung Pay based on "devices" such as Galaxy and Kakao Pay based on "service" such as KakaoTalk. This study contributes to analyzing the unstructured data of social media by period by using social media mining and quantifying the expectations and reactions of consumers to services through the sentiment analysis. It is expected to be the foundation of Fintech industry development by presenting a strategic direction to Fintech related practitioners.