• 전자공학회논문지B
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• 제33B권7호
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• pp.107-115
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• 1996

The average distortio of the vector quantizer is calcualted using a probability function F of the input source for a given codebook. But, since the input source is unknown in geneal, using the sample vectors that is realized from a random vector having probability function F, a time-average opeation is employed so as to obtain an approximation of the average distortion. In this case the size of the smple set should be large so that the sample vectors represent true F reliably. The theoretical inspection about the approximation, however, is not perfomed rigorously. Thus one might use the time-average distortion without any verification of the approximation. In this paper, the convergence characteristics of the time-average distortions are theoretically investigated when the size of sample vectors or the size of codebook gets large. It has been revealed that if codebook size is large enough, then small sample set is enough to obtain the average distortion by approximatio of the calculated tiem-averaged distortion. Experimental results on synthetic data, which are supporting the analysis, are also provided and discussed.

• Communications for Statistical Applications and Methods
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• 제28권5호
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• pp.463-475
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• 2021

Desgagné and de Micheaux (2018) proposed an alternative univariate normality test to the Jarque-Bera test. The proposed statistic is based on the sample second power skewness and kurtosis while the Jarque-Bera statistic uses sample Pearson's skewness and kurtosis that are the third and fourth standardized sample moments, respectively. In this paper, we generalize their statistic to a multivariate version based on orthogonalization or an empirical standardization of data. The proposed multivariate statistic follows chi-squared distribution approximately. A simulation study shows that the proposed statistic has good control of type I error even for a very small sample size when critical values from the approximate distribution are used. It has comparable power to the multivariate version of the Jarque-Bera test with exactly the same idea of the orthogonalization. It also shows much better power for some mixed normal alternatives.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2733-2737
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• 2014

Objective: Molecular pathology tests are often carried for clinicopathological diagnosis and pathologists have established large collections of formalin-fixed, paraffin-embedded tissue (FFPE) banks. However, extraction of DNA from FFPE is a laborious and challenging for researchers in clinical laboratories. The aim of this study was to compare two widely used DNA extraction methods: using a QIAamp DNA FFPE kit from Qiagen and a Cobas Sample Preparation Kit from Roche, and evaluated the effect of the DNA quality on molecular diagnostics. Methods: DNA from FFPE non-small cell lung carcinoma tissues including biopsy and surgical specimens was extracted with both QIAamp DNA FFPE and Cobas Sample Preparation Kits and EGFR mutations of non-small cell lung carcinomas were detected by real-time quantitative PCR using the extracted DNA. Results and Conclusion: Our results showed that DNA extracted by QIAamp and Cobas methods were both suitable to detect downstream EGFR mutation in surgical specimens. Howover, Cobas method could yield more DNA from biopsy specimens, and gain much better EGFR mutation results.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.1136-1139
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• 2002

The circular cavity resonator which can measure the dielectric properties of dielectrics in the Ka-band(26.5GHz~40GHz) frequency range was designed and fabricated. A structure of the resonator is divided into two equal parts of the length and the dielectric plate sample is placed between two halves. Exciting and detecting of the resonator is performed by WR28 rectangular waveguides using Bethe's small hole coupling. The GaAs plate sample, whose permittivity is known to be 13 in millimeter wave range, was used for the verification of the performance of the fabricated circular cavity resonator. In the measurement of GaAs single crystal using that resonator, the resonant frequency of the dominant $TE_{011}$ mode, the permittivity and $Q{\times}f_0$ were measured as 26.69GHz, 12.9 and 124,000GHz, respectively.

• Advanced Composite Materials
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• 제16권3호
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• pp.245-258
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• 2007

The single-modal Weibull model has been assessed on Tyranno ZMI Si-Zr-C-O fiber if a set of shape and scale parameters accurately reproduced the effect of the size of the diameter on strength. The tensile data of a single fiber have been divided into two expedient groups as 'small diameter' group and 'large diameter' group in deriving the parameters, which should be consistent if the Weibull model accurately reproduced the size effect. However, the derived Weibull parameters were inconsistent between the two groups. Thereby the authors have concluded that the parameters of the single-modal Weibull model are dependent on the fiber diameter, so that the model is inadequate to reproduce the strength size effect. On the other hand, Weibull parameters were found consistent between the two groups by excluding the data of 'large mirror zone' sample, which was defined as the sample around 10% mirror zone area of the fracture surface. What is more, the exclusion reduced the strength variance more drastically in the 'large diameter' group than in the 'small diameter' group, even though the 'large mirror zone' samples were found identical in the percentage between the two groups. The authors therefore conclude that diameter limitation to the 'small diameter' group level can lead to drastically less distributed strength values than the estimated strength through the Weibull scaling on the present Tyranno ZMI Si-Zr-C-O fiber.

• 천문학논총
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• 제20권1호
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• pp.125-134
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• 2005

In this paper, we propose a small-scale Gigabit VLBI observing system for the Korean VLBI Network (KVN) under construction. The system consists of high-speed sampler, IP-VLBI board, PC-VSI board, and software correlator. Radio signal received by receiver is sampled by high-speed sample. at 1 Gsps (Gigabit sample per second) rate with 2 bits quantization. The digitized signal is recorded in PC and the software correlator does the cross correlation. IP-VLBI board will be used for the geodesy VLBI observation, while PC-VSI board is for the astronomical VLBI observation. The PC-VSI board adopts the VSI-H (VLBI Standard Interface Hardware). The proposed system is based on commercial PCs and therefore can be built inexpensively.

• 한국전기전자재료학회논문지
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• 제15권12호
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• pp.1085-1089
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• 2002

The circular cavity resonator which can measure the dielectric properties of dielectrics in the Ka-band(26.5GHz∼400Hz) frequency range was designed and fabricated. A structure of the resonator is divided into two equal parts of the length and the dielectric plate sample is placed between two halves. Exciting and detecting of the resonator is Performed by WR28 rectangular waveguides using Bethe's small hole coupling. The GaAs plate sample, whose performance is known to be 13 in millimeter wave range, was used for the verification of the performance of the fabricated circular cavity resonator In the measurement of GaAs single crystal using that resonator, the resonant frequency of the dominant TE$\sub$011/ mode, the permittivity and Q${\times}$f$\sub$0/ were measured as 26.69GHz, 12.9 and 124,000GHz, respectively.

• The Journal of Asian Finance, Economics and Business
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• 제7권11호
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• pp.817-825
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• 2020

Over the last few decades, corporate frauds have highlighted the significance of corporate governance in deriving firm performance. By using different sample data, extensive research has examined how corporate governance structure influences firm's profitability, but limited research was undertaken on the banking sector of Pakistan. This research adds to the literature by testing how board structure derives bank's performance by using sample data of 19 banks for the period from 2010 to 2017. In addition, the study analyzes the controlling part of size on the link between board governance and bank performance. Findings reveal that banks having small board size, fewer non-executive directors and minimum activity level perform better. Analysis related to bank size illustrates that board size has value in increasing benefits in large size banks in contrast to small size one, while higher participation by board members enhances performance of small size banks more. The correlation results and findings showed that there existed no multicollinearity issue between independent variables. Board size showed positive correlation with the market variable, while board activity tended to correlated negatively with the market performance. Inverse correlation between board size and independent directors indicated that Pakistani banks with greater board size had fewer independent directors.

• The Journal of Asian Finance, Economics and Business
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• 제6권1호
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• pp.231-240
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• 2019

The paper aims to investigate the relationship between firm size and organizational actions on adopting social media for corporate reputation management. The sample group of 198 companies is selected with a simple random sample method from the New York Stock Exchange (NYSE) listings: Sixty nine companies were from the Fortune 500 listings, seventy one companies from the NYSE midsize capitalization and fifty eight companies from the NYSE small capitalization listings. This study employs cross tabulations and Chi-square analysis, and the Kruskal-Wallis that enables the comparison of three samples that are independent. The results of the study show that (1) large firms have more social media ownership than small firms, (2) large firms respond to social media posts at a greater frequency and quickly than small firms, and (3) firm size is less likely associated with response styles to social media for online reputation management. The results show that reply time and response styles of organizations to social media customers in the 2015 survey has no significant change compared to that of 2011. There appears to be a pervasive lack strategic framework as most firms in the study were found not to be adequately monitoring or leveraging social media communication for their reputation management.

• 유통과학연구
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• 제20권6호
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• pp.57-66
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• 2022

Purpose: Business agility is an important key to survival for SMEs in Indonesia, especially during the COVID-19 pandemic. Indonesian local product distribution and service distribution are mostly served by SMEs. Agile businesses will be able to assist them in the proper distribution of products and services. This research examines how the direct and indirect influence of IT capabilities on business agility through organizational learning and business intelligence for small and medium enterprises in the distribution of Indonesian products and services. Research design, data and methodology: This research uses SEM method with SmartPLS tool. The sample of this research was conducted on small and medium enterprises in the distribution of Indonesian products and services. The sample obtained in this study was 202 SME owners or managers (strategic level). Results: Business intelligence plays a key role in improving business agility. The results of IT capability can directly and indirectly affect business agility through organizational learning. Conclusions: Business intelligence has the biggest role in increasing business agility in SMEs in Indonesia. IT capability has an indirect effect on business agility through organizational learning. The findings of this study prove that IT capabilities do not indirectly affect business agility through business intelligence.