• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.219-229
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• 2007

The results of the research in M&A firms in the KOSDAQ market are as follows. First, the effect of the M&A disclosure at the time of disclosure was that the positive (+) cumulative abnormal return (CAR) can be interpreted as an increase in the value of the firm; however, in the long run, firms which used the KOSDAQ index and the control firm, which did not use the index were found to have conflicting results. Second, the findings show that the rise in value of general firms resulting from a M&A were higher that those of venture firms. Third, in testing the performance extrapolation hypothesis, it was shown that the performance of "value" firms (firms with a high B/M ratio but poor performance in the past) was better after a M&A than those of the "glamour" firms and that the performance extrapolation hypothesis was substantiated. Fourth, it can be construed that a size effect in a merger exists. The CAR of the small firms surpasses those of large firms. Fifth, in verifying operating performance, most variables showed a positive (+) value at the time of M&A but showed a negative (-) value after a M&A. These results show that because on the Korean KOSDAQ market, M&A are approached from a financial rather than an economic aspect, it can be inferred that it lowers the firms value.

• Journal of Sensor Science and Technology
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• v.9 no.4
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• pp.316-326
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• 2000

A new signal processing algorithm for white light interferometry has been proposed and investigated theoretically. The goal of the algorithm is to determine the absolute optical path length of an interferometer with very high precision (<< one optical wavelength). The algorithm features cross-correlation of interferometer fringe scans and hypothesis testing. The hypothesis test looks for a zero order fringe peak candidate about which the cross-correlation is symmetric minimizing the uncertainty of misidentification. The shot noise limited performance of the proposed signal processing algorithm has been analyzed using computer simulations. Simulation results were extrapolated to predict the misidentification rate at Signal to-Shot noise ratio (SNR) higher than 31 dB. Root-mean-square phase error between the computer-generated zero order fringe peak and the estimated zero order fringe peak has been calculated for the changes of three different parameters (SNR, fringe scan sampling rate, coherence length of light source). Results of computer simulations showed the ability of the proposed signal processing algorithm to identify the zero order fringe peak correctly. The proposed signal processing algorithm uses a software approach, which is potentially inexpensive, simple and fast.