• Proceedings of the Korean Society of Laser Processing Conference
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• 2000.06a
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• pp.15-19
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• 2000

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.273-283
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• 1996

In order to search for anti-influenza virus type A agents from Korean traditional prescriptions (herb complexes), we selected 63 traditional prescriptions, based on a review of the Korean traditional medicine books. Both methanol extracts and boiling-water extracts were tested, by means of the Haemagglutination Inhibition Test (HIT). Three of the 63 methanol extracts: CM-22, CM-26, CM-48 (see explanation of nomenclature below), showed efficacy against influenza virus type ACM-22 showed anti-influenza virus type A activity at the range of $313{\mu}g/ml$ to $9.75{\mu}g/ml$, CM-26 showed antiviral activity at the range of $156{\mu}l/ml$ to $4.87{\mu}g/ml$, CM-48 showed anti-influenza virus type A activity at the range of $625{\mu}g/ml$ to $19.5{\mu}g/ml$, respectively. Three of the water extracts: CW-14, CW-34, CW-61 were active. CW-14 showed anti-influenza virus type A activity at the range of l0mg/ml to $78{\mu}g/ml$, CW-34 showed antiviral activity at the range of 10mg/ml to $625{\mu}g/ml$ and CW-61 showed anti-influenza virus type A activity at the range of l0mg/ml to $313{\mu}g/ml$, respectively. In order to determine cytotoxicity of each extracts, chicken red blood cells were incubated with the various concentration of extracts of Korean traditional prescriptions. CW-14, CW-34 and CW-61 did not show cytotoxic effect against red blood cells whereas CM-22, CM-26 and CM-48 showed cytotoxic effect against red blood cells at the range of l0mg/ml to $625{\mu}g/ml$, 10mg/ml to $313{\mu}g/ml$ and 10mg/ml to $313{\mu}g/ml$, respectively. These results indicated that Korean traditional pres criptions may be inhibit either attachment of virus to cell surface receptor or penetration of the virus into cell during the initial stage of infection.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.6
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• pp.617-626
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• 2010

In this paper, we have proposed and experimentally performed a polarization and phase control method of an optical signal which has same wavelength with the optical carrier to improve phase characteristics of a continuous wave(CW) generated by the double sideband-suppressed carrier(DSB-SC) as one of the famous photomixing technique for making sub-millimeter and terahertz waves. A polarization and phase controlled optical signal has been coupled with the general DSB-SC on an optical coupler. The output of the optical coupler is then photomixed by a photomixer. From our analysis and measurement results, we have found that the amplitude of the generated sub-mm and terahertz CW signal is higher 1.5 dB and the phase noise is lower about 3 dB@10 kHz offset frequency than the general DSBSC. Consequently, since our proposed method has improved the amplitude and phase noise of CW signals in the sub-mm and terahertz bands, it can be helpful results to make low cost CW generator in sub-millimeter and subterahertz bands.

• The Journal of the Acoustical Society of Korea
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• v.30 no.1
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• pp.33-41
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• 2011

To substitute TLS in the hybrid system which is combined with Sagnac interferometer and fiber bragg grating (FBG) it is necessary to investigate how the laser source (TLS and CW) and sensor material variate the response of fiber optic sensor. Two different hollow cylinder type mandrel materials are proposed which are PTFE and PTFE+carbon and 18 m optical fiber is wounded at the mandrel surface. CW laser source experiments had been done in the oil tank which is filled with transformer oil in the 1 kHz~20 kHz frequency range. Also Sagnac interferometer fiber optic sensor is combined with FBG called hybrid system and TLS used as a light source. Based on the experimental results PTFE sensor showed more higher magnitude of detection signal rather than carbon sensor and this result is agreement with the McMahon's theoretical results. Phase variation is inversely proportional to the elastic modulus of the mandrel material. In PTFE fiber sensor, tunable laser source showed more higher performance rather than CW case. Therefore, TLS fiber optic sensor can be applied to the hybrid system which is combined with Sagnac and FBG.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.550-553
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• 2000

Optimum temperature for paralytic shellfish poison (PSP) detoxofication of Enterobacter sp. CW-6 isolated from sea water and changes of contents and ingredients composition of PSP during bacterial detoxification process were investigated. Enterobacter sp. CW-6 detoxicated $61.5{\~}67.7{\%}\;and\;87.4{\~}96.8{\%}$ of initial PSP toxicity ($25.0{\~}28.5\;nmole/g$) after $5{\~}12$ days at 30 and $35^{\circ}C$, identified as optimal growth temperature, respectively. The detoxification rate of Enterobacter sp. CW-6 for crude PSP with initial concentration of 38.2 nmole/g after 8 and 12 days at $30^{\circ}C$ in the Marine broth was 88.4 and $92.7{\%}$, respectively. During bacterial detoxification process using crude toxin solution, temporary increasement of STX group was detected and identified that was derived from GTX2, 3 group. The detoxification rate of Enterobaoter sp. CW-6 on purified GTX1 and 4 with initial concentration 47 nmole/g and 37 nmole/g were more than $90{\%}$ after 12 days in the marine broth at $30^{\circ}C$. Enterobacter sp. CW-6 also showed a detoxification activity on purified GTX2 and 3, and the detoxification rate for the initial concentration 25.6 nmole/g after 12 days was $66.4{\%}$.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.166-172
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• 2003

Rockwool slabs used for hydroponic cultures are expected to have potential to be reused after breakdown as a growing medium component for hydroponic culture of vegetables and cut flowers, pot plants, or plug plants. This study was conducted to test the feasibility of using particles of used rockwool slabs (PURS) mixed with woodchips for growing plug seedlings of ‘Nokkufang’ pepper. In the first experiment growth of pepper seedlings was tested in media of steam sterilized PURS mixed with chestnut woodchips (CW), which was weatherized for six months and screened through 2.8 mm or 5.6 mm sieves, at 100:0, 75:25, 50:50, 28:75 or 0:100 (%, v/v). In the second experiment growth of pepper seedlings was tested in 20 different media containing steam sterilized PURS mixed with 4 mm chestnut woodchips (CW), 4 mm pinc woodchips (PW), coir, peatmoss, or perlite. In the first experiment, there were no significant growth differences as affectcd by particle size of CW, while the overall best growth was achieved il1 the control and l00% PURS. In the second experiment, seedling growth was enhanced as compared to the control in 100% PURS or PURS mixed with peatmoss, coir, or perlite. In contrast, growth was suppressed as the proportion of peatmoss or coir mixed with PURS decreased and the proportion of CW increased. Growth was better in the PURS + peatmoss than in the 100% PURS or PURS + coir, and when woodchips were mixed with coir than peatmoss.

• Journal of Advanced Navigation Technology
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• v.25 no.5
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• pp.426-432
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• 2021

Continuous wave (CW) Doppler radar has the advantage of being able to solve the privacy problem unlike camera and obtains signals in a non-contact manner. Therefore, this paper proposes a human activity recognition (HAR) system using CW Doppler radar, and presents the hardware design and implementation results for acceleration. CW Doppler radar measures signals for continuous operation of human. In order to obtain a single motion spectrogram from continuous signals, an algorithm for counting the number of movements is proposed. In addition, in order to minimize the computational complexity and memory usage, binarized neural network (BNN) was used to classify human motions, and the accuracy of 94% was shown. To accelerate the complex operations of BNN, the FPGA-based BNN accelerator was designed and implemented. The proposed HAR system was implemented using 7,673 logics, 12,105 registers, 10,211 combinational ALUTs, and 18.7 Kb of block memory. As a result of performance evaluation, the operation speed was improved by 99.97% compared to the software implementation.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.10
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• pp.60-66
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• 2011

In this paper, we analyze the effects of estimation error in the active cancellation signal, which is intended to counter the pulsed-CW signal of a hostile radar. We also examine the effects of estimation error in maximum-likelihood estimation (MLE) and quadratic interpolation scheme from a radar signal active cancellation viewpoint. Then, we modify the correlation-based error compensation scheme which mitigates the estimation error of MLE to improve the performance of the active cancellation signal. Finally, we present simulation results to show that the correlation-based scheme has better performance than the other in terms of radar signal active cancellation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.7
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• pp.815-821
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• 2012

A CW Doppler radar can measure radial velocity of an object. It detects a Doppler frequency shift that is proportioned to radial velocity of a moving object. To detect a Doppler frequency shift, FFT(Fast Fourier Transform) is conducted. In this process, the time domain received signal is transformed to a frequency domain. A number of FFT affects not only the time resolution but also signal to noise ratio of received signal. So finally it is related with a radial velocity accuracy. Therefore in this paper, it is described the relation of time resolution and the radial velocity accuracy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1532-1535
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• 2009

This paper describes a K-band CW radar transceiver suitable for power saving motion sensor. The presented transceiver module is designed and contains patch antennas, dielectric resonator oscillator (DRO), IF amplifier, mixer, divider. The designed divider and antenna are measured and the transmitting frequency and the power were fairly good for using in commercial applications. The transceiver is manufactured with a dimension of 35${\times}$35${\times}$10(mm) and can be adapted in various applications.