• Resources Recycling
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• v.12 no.6
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• pp.26-31
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• 2003

The power loss characteristics of Mn-Zn ferrite were observed with the sintering temperature. In case of $1150 ^{\circ}C$ sintering, the core loss increased with measuring temperature, and does not have minimum value at the point where the magnetocrystalline anisotropy be 'zero'. This reason mainly due to the change of core loss mechanism with grain size which affects residual loss. The grain size and sintered density slightly increased with equilibrium oxygen partial pressure at$ 1150 ^{\circ}C$ sintering. The resistivity and initial permeability showed no significance with atmosphere, these results due to complex effect of $Fe^{2+}$ concentration and microstructure change. The core loss at $100^{\circ}C$ decreased as the equilibrium oxygen partial pressure increased.e increased.

• Journal of Korean Society of Transportation
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• v.30 no.5
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• pp.61-69
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• 2012

It is important for highway maintenance and safety assessment to get the accurate highway geometric information. However, it is difficult to acquire good highway geometric information due to missing blueprints or deteriorated highway sections. This research, to get highway geometric information rapidly, has developed a highway geometric analysis algorithm that uses data from vehicles with GPS-IMU integrated system. In conclusion, the result shows that 3.38% of error-ratio for the horizontal alignment and 0.083 absolute value difference for vertical grade comparing with highway drawings. Therefore, the result suggest that the developed method can be applied to the road safety inspection or road safety audit.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.4
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• pp.31-43
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• 1999

The main goal of this paper is to design a high performance SVP(Stack based Video Processor) for network applications. The SVP is a comprehensive scheme; 'better' in the sense that it is an optimal selection of previously proposed enhancements of a stack machine and a video processor. This can process effectively object-based video data using a S-RISC(Stack-based Reduced Instruction Set Computer) with a semi -general-purpose architecture having a stack buffer for OOP(Object-Oriented Programming) with many small procedures at running programs. And it includes a vector processor that can improve the MPEG coding speed. The vector processor in the SVP can execute advanced mode motion compensation, motion prediction by half pixel and SA-DCT(Shape Adaptive-Discrete Cosine Transform) of MPEG-4. Absolutors and halfers in the vector processor make this architecture extensive to a encoder. We also designed a VLSI stack-oriented video processor using the proposed architecture of stack-oriented video decoding. It was designed with O.5$\mu\textrm{m}$ 3LM standard-cell technology, and has 110K logic gates and 12 Kbits SRAM internal buffer. The operating frequency is 50MHz. This executes algorithms of video decoding for QCIF 15fps(frame per second), maximum rate of VLBV(Very Low Bitrate Video) in MPEG-4.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.10
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• pp.66-74
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• 2008

Surveillance system using active tracking camera has no distance limitation of surveillance range compared to supersonic or sound sensors. However, complex motion tracking algorithm requires huge amount of computation. Compared to conventional methods using DSPs or embedded processors, this paper proposes and implements a novel motion tracker unit that detects and extracts motion information of moving objects by using picture difference of consecutive frames. The proposed motion tracker unit was implemented in FPGA with about 13,000 gates. It processes NTSC format video and was verified by embedding it into the active surveillance camera system. We also propose and implements a motion estimator unit linkable to video codec by embedding the proposed motion tracker unit into ready-made motion estimator unit. The implemented motion estimator unit is about 17,000 gates in $0.35{\mu}m$ process.

• Journal of IKEEE
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• v.7 no.1 s.12
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• pp.22-31
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• 2003

Conventional stimulus patterns have used DC for discrimination of acupoint and meridian which is the basic object of diagnosis and medical treatment in oriental medicine. Those discriminate conduction points by stimulation on body skin with DC. But, it is insufficient to reliability in discrimination ratio, coincident ratio, body effect, reproductivity. Therefore, this paper has extracted the optimal parameter of frequency and waveform in order to improve conventional pattern, and proposed the SPAC(Single Power Alternative Current) stimulus pattern applying that. Also, We proposes algorithm which is able to discriminate with low pressure of the electrode by displaying in the level meter both the absolution and relation value of the skin current. It can decrease pain and body effect by electrode pressure and discriminate acupoint regardless of skin current in difficult discrimination spot. We have compared the performance of system applying the extracted optimal parameter and algorithm. We have compared discrimination, coincident ratio of both conduction point and traditional acupoints by acupoint stimulation pattern. In the results, we confirmed reliability of SPAC stimulus pattern.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.7
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• pp.723-728
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• 2016

This study is analyzed the optical property of red tide pixel by using Landsat-7 ETM+, Landsat-8 OLI and COMS/GOCI image. In order to sample red tide pixel, Landsat-7, 8 true color image were used and obtained coordinate of red tide pixel in the true color image. Normalized water leaving radiance(nLw) and absorption coefficient were obtained from GOCI image in the same coordinate of the true color image. When red tide was not occurred the main absorption range was 412nm and 660nm but when red tide occurred it was 660nm and absorption coefficient in 412nm are drastically reduced. It made no difference of nLw spectrum between red tide pixel and non red tide pixel in nLw, but the absolute value of nLw was low than non red tide pixel, especially 660nm and 680nm wavelength sharply decrease.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.301-308
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• 1995

To establish the quality criteria of low-salt fermented seafoods in terms of consumer acceptability, sensory assessment and physicochemical analysis were undertaken using commercial products. In case of low-salt fermented Alaska pollack (Theragra chalcogramma) roe, Brix over $47.6\%$ for unseasoned products and $41.2\%$ for seasoned ones were considered as acceptable products. In spite of some variations between manufacturers, increase in whiteness was observed as consumer acceptability was decreased. In contrast, whiteness was not suitable criteria for low-salt fermented squid (Sepiella maindroni). Brix can be used as good criteria as long as its relationship was established to acceptability of different products; pH also showed the same tendency as Brix. In case of low-salt fermented Alaska pollack tripe, Brix was likely to be the best criteria; whiteness, in addition, could be used as quality criteria.

• Journal of Labour Economics
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• v.25 no.2
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• pp.1-32
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• 2002

This paper investigates how real wages adjust to regional and cyclical shocks in the Korean labor market. Major findings are as follows. First, like most longitudinal studies in this literature, we find that real wages are strongly procyclical and more procyclical for men than for women. Second, consistent with the theory prediction of efficiency wages, both permanent and transitory components of real wages are negatively correlated with the local unemployment rate. Third, when overall and local unemployment rates compete in a wage equation (our preferred specification), current wages are dominantly affected by the overall rate, and the effect of the local rate is rather small. This rejects the Blanchflower and Oswald's hypothesis that wages are primarily determined by local labor market conditions. Finally, no lagged effects on wages are detected in the overall or local unemployment rate.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.5
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• pp.117-123
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• 2003

One of the most important elements in satellite attitude control is sensor technology. Generally, inertial sensors introduce drift and noise which cause continuous errors. Absolute reference is needed to eliminate the problem of the inertial sensors. Star trackers are used primarily for such a purpose. There has been relatively less research effort or ground feasibility test experience on star trackers in the domestic side despite the importance of the associated technologies. In this paper, we re-introduce the basic concept of a star tracker and present the S/W simulator for the star tracker. The star simulator may be used ground test of a star tracker for the basic functioning test or the whole spacecraft test with the star tracker assembled.

• Journal of Broadcast Engineering
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• v.4 no.2
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• pp.127-133
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• 1999

The conventional fractal image compression based on discrete wavelet transform uses the fixed block size in fractal coding and reduces PSNR at low bit rate. This paper proposes a fractal image coding based on discrete wavelet transform which improves PSNR by using variable block size in fractal coding. In the proposed method. the absolute values of discrete wavelet transform coefficients are computed. and the discrete wavelet transform coefficients of different highpass subbands corresponding to the same spatial block are assembled. and the fractal code for the range block of each range block level is assigned. and then a decision tree C. the set of choices among fractal coding. "0" encoding. and scalar quantization is generated and a set of scalar quantizers q is chosen. And then the wavelet coefficients. fractal codes. and the choice items in the decision tree are entropy coded by using an adaptive arithmetic coder. This proposed method improved PSNR at low bit rate and could achieve a blockless reconstructed image. As the results of experiment. the proposed method obtained better PSNR and higher compression ratio than the conventional fractal coding method and wavelet transform coding.rm coding.