• Journal of the Korean Wood Science and Technology
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• v.46 no.2
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• pp.125-131
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• 2018

This study was conducted to understand and to compare the qualitative aspects of anatomical characteristics in compression wood (CW), lateral wood (LW), and opposite wood (OW) in a stem of Ginkgo biloba. The qualitative analysis was examined by optical microscopy and scanning electron microscopy. CW in Ginkgo biloba disks were dark brown in color, and the OW and LW were light brown in color. CW and OW showed abrupt transitions from earlywood to latewood, while LW showed a gradual transition. Cross sections of CW presented circular tracheids with angular outlines, many intercellular spaces, and varying sizes of lumens. Cross sections of LW and OW showed rectangular tracheids, fewer intercellular spaces, and varying sizes of lumens. In radial sections, CW showed an irregular arrangement of tracheids in earlywood, while LW and OW showed comparatively regular arrangements. Slit-like bordered pits on the tracheid cell wall, piceoid pits in the crossfield, and a few spiral checks were present in CW. LW and OW showed bordered pits with slightly oval-shaped apertures, as well as cuppresoid pits in the crossfields. Rays were primarily uniseriate, with few biseriate rays in the tangential sections of CW, LW, and OW. The tips of the tracheids were branched in CW but had a normal appearance in LW and OW.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.12
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• pp.2911-2916
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• 2015

The CCTV is limited by weather conditions. To overcome this limitation, we develop a monitoring program that can sense the approach or recede of two or more objects within a surveillance system that uses a continuous-wave (CW) Doppler radar, and we proposed an algorithm to efficiently detect the approach or recede information of the object. The proposed algorithm separates the signal received by the CW Doppler radar into the real and imaginary parts using Fast Fourier Transform (FFT), and sums the amplitudes for each frequency to determine whether the objects are approaching or receding, using their locations. The algorithm is verified by simulations and experiments, which confirms that it successfully detects the approach or recede of two objects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.4
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• pp.380-386
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• 2009

Molting and growth of the snow crab, Chionoecetes opilio was investigated using samples captured in the East Sea from July 2002 to June 2004. Individuals over 40 mm carapace width (CW) molted once a year from July to October. Annual molt stage of C. opilio can be divided into four stages; premolt stage, molting stage, postmolt stage and intennolt stage. The relationship between CW and chela height (CH) can be expressed as Y=-82lnCW+73.1129lnCH+166. They were separated into two groups based on the equation, that is, one group having a negative value (below 70 mm in CW) and other group having a positive value (over 130 mm in CW). Carapace width at 50% terminal molt ($CW_{50%}$) of males was estimated to be 105 mm. The Gompertz growth equation estimated from a non-linear method was $CW=118.99e^{-6.296e^{-0.3062t}}$ for females and $CW=156368e^{-6.6619e^{-0.2626t}}$ for males.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.546-549
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• 2000

For the establishment of biodetoxification method which can be acceptable for live bivalves, paralytic shellfish poison (PSP) detoxification bacteria were isolated from sea water and bivalves, and PSP detoxification activity and optimal growth condition of the isolated strains were investigated. from the bivalve and sea water samples, 8 strains of PSP detoxification bacteria were isolated. Of the isolated strains, CW-6 isolated from sea water shown strong PSP detoxification activity and decomposed completely 18 nmole/g of GTX2 after 3 days incubation in artificial medium. The selected stain CW-6 shown typical characteristics of the Enterobacter sp. and identified as Enterobacter sp, CW-6. Optimal growth condition of the Enterobacter sp. CW-6 were $35^{\circ}C$, pH 7 and $NaCl 1{\%}$, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.4
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• pp.363-372
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• 1997

We have developed the UHF CW/FM proximity sensor system. The UHF CW/FM Proximity Sensor is the system which recognizes the distance from the antenna to the target using the UHF band signal. To adjust sensing distance, we must change modulation frequency parameter or modulation index parameter. When we select the modulation frequency paramter for adjusting sensing distance, new modulation frequency generator and new band pass filter will be required. It is so inefficient that we choose modulation index parameters for adjusting sensing distance. In this paper, theoretical principles of the UHF CW/FM Proximity Sensor are analyzed and doppler signals for the distance from the antenna to the target are measured as the modulation index($\beta$) being changed. Three systems of which moduation indices are 38, 50, and 61 are made. We concluded that the sensing distance will decrease as the modulation index($\beta$) increases. It is in accord with the theory of this UHF CW/FM Proximity Sensor System.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.8
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• pp.1752-1758
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• 2010

A FM-CW radar is used for the various purposes as a remote sensing device since it has the advantages of the relatively simple implementation and the low probability of signal interception. A FM-CW radar uses the same frequency modulated continuous wave for both transmission and demodulation. Therefore, the received beat frequency represents the range and Doppler information of targets. However, using the conventional FFT method, the degree of accuracy and resolution in the spectrum estimation can be seriously degraded in the detection and tracking of fast moving targets because of the short dwell time. Therefore, in this paper, the model parameter estimation methods called as an autoregressive method is applied to overcome these problems and showed that the improved accuracy and resolution can be obtained for the target range and velocity estimation.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.51-58
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• 2006

The objective of this research work is to investigate into heat transfer characteristics of the laser cutting of CSP 1N sheet using high power CW Nd:YAG laser. In order to investigate the heat transfer characteristics, three dimensional quasi stationary and steady-state heat transfer analysis has been carried out. The laser heat source is assumed as a volumetric heat source with a gaussian heat distribution in a plane. Through the comparison of the results of analyses with those of experiments, the proper finite element model has been obtained. In addition, characteristics of the three-dimensional heat transfer and temperature distribution have been estimated by the finite element model. Finally, the minimum temperature at the center for cutting of the material has been estimated.

• Journal of Positioning, Navigation, and Timing
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• v.1 no.1
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• pp.23-27
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• 2012

Recently, devices like Personal Privacy Devices (PPD) are being employed to avoid the detection of one's location by GPS, and most PPD transmits swept CW signals. However, signals transmitted from PPD may interfere a precise location system based on GPS. Accordingly, in order to reduce interferences by PPD, a technique to locate an interferer is needed. In order to locate an interferer AOA method and TDOA method are generally used, TDOA method is known to be more accurate than AOA method. Unfortunately, TDOA method has a problem of ambiguity in obtaining measurements of swept CW interference. Thus, this paper design a localization algorithm based on TDOA method that can accurately locate an interferer transmitting swept CW signals by resolving problem of ambiguity. In addition, feasibility of the designed algorithm has been verified by simulation results.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.127-130
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• 1999

본 논문에서는 수신된 CW 신호로부터 Morse 코드를 자동 인식하는 알고리듬을 제안하였다. 전체 알고리듬은 수신된 CW 신호로부터 잡음 및 간섭신호 성분을 제거하고 신호의 존재유무를 판정하는 부분, 신호 길이의 변화를 극복하여 Morse 코드의 요소(Long, Short, Null set)로부터 코드로 판독하는 부분으로 구성되었다. 제안된 알고리듬은 CW 신호의 주파수, 위상 및 길이 정보가 필요 없으며, 모의 실험 결과, SNR -15dB, $20\%$의 신호 길이 변화 환경에서도 $100\%$의 해석률을 나타내었다.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.241-242
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• 1996

The UBV observations of the close binary system CW Cephei were made from August 198:3 to December 1984 during 25 nights using the 61cm Boller and Chivens reflector at the Sobaeksan Astronomy Observatory. The new UBV light curves were analyzed with the recent Wilson-Devinney binary model. Our photometric solution for CW Cep were well consistent with those of Clausen &. Gimenez (1991). Using our photometric solution and Popper & Hill (1991) spectroscopic one, each absolute masses and radii of components for CW Cep were derived as 13.63 M$\bigodot$ and 5.83 R$\bigodot$ for the primary, and 12.18 M$\bigodot$ and 5.14 R$\bigodot$ for the secondary, respectively.