• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.3
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• pp.3-9
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• 2017

Recently, in 3rd Generation Partnership Project(3GPP), there is a study of the Long Term Evolution(LTE) based vehicle communication which has been actively conducted to provide a transport efficiency, telematics and infortainment. Because the vehicle communication is closely related to the safety, it requires a reliable communication. Because vehicle speed is very fast, unlike the movement of the user, radio channel is rapidly changed and generate a number of problems such as transmission quality degradation. Therefore, we have to continuously updates the channel estimates. There are five types of conventional channel estimation scheme. Least Square(LS) is obtained by pilot symbol which is known to transmitter and receiver. Decision Directed Channel Estimation(DDCE) scheme uses the data signal for channel estimation. Constructed Data Pilot(CDP) scheme uses the correlation characteristic between adjacent two data symbols. Spectral Temporal Averaging(STA) scheme uses the frequency-time domain average of the channel. Smoothing scheme reduces the peak error value of data decision. In this paper, we propose the novel channel estimation scheme in LTE based Vehicle-to-Vehicle(V2V) environment. In our Hybrid Reliable Channel Estimation(HRCE) scheme, DDCE and Smoothing schemes are combined and finally the Linear Minimum Mean Square Error(LMMSE) scheme is applied to minimize the channel estimation error. Therefore it is possible to detect the reliable data. In simulation results, overall performance can be improved in terms of Normalized Mean Square Error(NMSE) and Bit Error Rate(BER).

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.342-347
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• 2007

The dried fruit of the Rubus coreanus, which is well-known in Korea and referred to as 'Bokbunja,' has been employed as a traditional medicine for centuries. This crude drug has been utilized in Korea for the management of impotence, spermatorrhea, enuresis, asthma, and allergic diseases. Our previous study demonstrated that the ethanol extracts of R. coreanus have anti-inflammatory effects. The principal objective of the present study was to conduct a comparison of the anti-inflammatory effects of the ethanol extracts of R. coreanus and R. occidentalis; here, we tested the unripe (URCE), half-ripened (HRCE), and ripened fruits (RCE) of R. coreanus, and the unripe (UROE), half-ripened (HROE), and ripened fruits (ROE) of R. occidentalis. We found that URCE, UROE, HRCE, and HROE reduced the production of nitric oxide and prostaglandin $E_{2}$ as well as pro-inflammatory cytokines in lipopolysaccharide-stimulated RAW264.7 murine macrophages. Interestingly, the R. coreanus extracts showed stronger inhibitory effects on the production of these inflammatory mediators than the R. occidentalis extracts.