• Analytical Science and Technology
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• v.18 no.1
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• pp.51-58
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• 2005

A comparison of the analytical data obtained by three $k_0$-NAA software programs was carried out using both the airborne particulate matter collected from an urban site and the certified reference materials of the air filter and urban dust to evaluate the performance of the analysis. The individual $k_0$-NAA standardization methods of three countries, Korea, China and Vietnam which had been modified from the well established $k_0$-program were used for the comparative analysis. The measured concentrations of 30 elements from the two kinds of air samples based on this software were in agreement with each other within about 20% analytical error except for a few elements. By contrast, the results of China and Vietnam were moderately higher than that of Korea due to a systematic error associated with the detection efficiency, gamma peak analysis and geometric effect.

• Journal of the Korean Vacuum Society
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• v.11 no.4
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• pp.218-224
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• 2002

A domestic round robin test(RRT) for the quantitative analysis of minor impurities was performed by a standard procedure and standard reference material. The certified reference material(CRM)s for B-doped Si thin film and analysis specimens and the analysis specimens were prepared by an ion beam sputter deposition method. These samples were certified by inductively coupled plasma mass spectrometry(ICP-MS) with isotope dilution method which il one of the most quantitative methods in chemical analysis. By using an international standard procedure(ISO/DIS-l4237) for the quantitative analysis of B in Si by SIMS, a domestic RRT was performed for these specimens. Although only a few laboratories participated in this RRT, the average B concentration well agreed with the certified value within 2% error.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.12
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• pp.2311-2317
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• 2011

In this paper, we study the temperature change of a ${\mu}$-bolometer focal plane array with a capacitive transimpedance amplifier bias cancellation circuit. Thermal analysis is essential to understand the performance of a ${\mu}$-bolometer focal plane array, and to improve the temperature stability of a focal plane array characteristics. In this study, the thermal analyses of a ${\mu}$-bolometer and its two reference detectors are carried out as a function of time. The analyses are done with the $30{\mu}m$ pitch $320{\times}240$ focal plane array operating of 60 Hz frame rate and having a columnwise readout. From the results, the temperature increase of a ${\mu}$-bolometer in FPA by an incident IR is estimated as $0.689^{\circ}C$, while the temperature increase by a pulsed bias as $7.1^{\circ}C$, which is about 10 times larger than by IR. The temperature increase of a reference detector by a train of bias pulses may be increased much higher than that of an active ${\mu}$-bolometer. The suppression of temperature increase in a reference bolometer can be done by increasing the thermal conductivity of the reference bolometer, in which the selection of thermal conductivity also determines the range of CTIA output voltage.

• Korean Journal of Clinical Pharmacy
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• v.23 no.2
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• pp.123-128
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• 2013

Purpose: The aim of study was to investigate the racial or ethnic differences in FDA-approved medications. Methods: Data on racial-based differences of drugs in PDR (Physician's Desk Reference) were analyzed by searching with keywords, "ETHNIC" and "RACE". Results: There were descriptions related to "ETHNIC" in product directions of 53 cases and "RACE" in 266 cases in 2010 PDR. After excluding 30 cases of duplicates, 289 cases were shown of which 28 cases were verified to demonstrate racial or ethnic differences. Drug category showing the higher racial or ethnic differences was cardiovascular drugs (7), followed by alimentary tract and metabolism drugs (6), nervous system drugs (5), and antineoplastic and immunomodulating agents (3). Pharmacokinetic differences between race and ethnicity were observed most frequently; differences in AUC or Cmax showed in 15 drugs and clearance differences in 7 drugs. Conclusions: This study identified the racial differences in medication usage in PDR. Therefore, the results can contribute to safe use of medication in real clinical settings in regards to the racial or ethnic differences.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.11a
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• pp.185-188
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• 2008

영상의 화질을 평가하는 방법은 어떤 정보를 기준으로 평가하느냐에 따라서 전체 기준법 (Full Reference), 부분기준법 (Reduced Reference) 그리고 무기준법 (No Reference)으로 나눌 수 있다. 이중 무기준법은 수신 영상만을 가지고 측정하기 때문에, 다른 방법보다 활용범위가 넓다. 또한, 최근 사람의 눈의 특성을 고려한 인지적(Perceptual)화질평가 방법이 많이 논의되어, 사람이 실제 보고 느끼는 바를 객관화 시키는 방법이 개발되어 왔다. 이들 화질평가 방법들에 대해 많은 연구가 수행되고 있으며, 국제기구들을 통하여 이들 지표들에 대한 표준화가 진행되고 있다. 본 논문에서는 휘도, 색차의 분포도를 분석하여 원본의 화질을 예측하는 방법을 통해서, 기존 무기준법의 정확도를 높이고자 한다. 영상신호의 양자화나 부호화로 인해 임계값을 벗어나는 값들이 생기게 되며, 이 값을 휘도, 색차의 분포도 분석으로 예측하여 화질평가를 수행하게 된다. 실험 결과 제안된 방법의 상관도는 다른 방법보다 높은 것으로 나타났다.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.301-309
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• 2011

The filamentous fungus Fusarium graminearum is an important cereal pathogen. Although quantitative realtime PCR (qRT-PCR) is commonly used to analyze the expression of important fungal genes, no detailed validation of reference genes for the normalization of qRT-PCR data has been performed in this fungus. Here, we evaluated 15 candidate genes as references, including those previously described as housekeeping genes and those selected from the whole transcriptome sequencing data. By a combination of three statistical algorithms (BestKeeper, geNorm, and NormFinder), the variation in the expression of these genes was assessed under different culture conditions that favored mycelial growth, sexual development, and trichothecene mycotoxin production. When favoring mycelial growth, GzFLO and GzUBH expression were most stable in complete medium. Both EF1A and GzRPS16 expression were relatively stable under all conditions on carrot agar, including mycelial growth and the subsequent perithecial induction stage. These two genes were also most stable during trichothecene production. For the combined data set, GzUBH and EF1A were selected as the most stable. Thus, these genes are suitable reference genes for accurate normalization of qRT-PCR data for gene expression analyses of F. graminearum and other related fungi.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.9
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• pp.1583-1589
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• 2016

This paper proposes an improved spread spectrum time domain reflectometry (ISSTDR) using time-frequency correlation and reference signal elimination method in order to have more accurate fault determination and location detection than conventional (SSTDR) despite increased signal attenuation due to the long distance to cable fault location. The proposed method has a two-step process: the first step is to detect a peak location of the reference signal using time-frequency correlation analysis, and the second step is to detect a peak location of the correlation coefficient of the reflected signal by removing the reference signal. The proposed method was validated through comparison with existing SSTDR methods in open-and short-circuit fault detection experiments of low voltage power cables. The experimental results showed that the proposed method can detect correlation coefficients at fault locations accurately despite reflected signal attenuation so that cable faults can be detected more accurately and clearly in comparison to existing methods.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.389-396
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• 2003

This paper presents experimental validation of the enhanced reference stress based J estimates for circumferential through-wall cracked pipes, recently proposed by authors. Using the pipe test data for circumferential through-wall cracked pipes, the predicted fracture initiation and maximum moments according to the proposed enhanced reference stress method are compared with experimental ones as well as predictions from the R6 method. The results show that both the R6 method and the proposed method give conservative estimates of initiation and maximum moments for circumferential through-wall cracked pipes, compared to experimental data. For longer cracks, the proposed method reduces conservatism embedded in estimated J according to the R6 method, and the resulting predictions are less conservative, compared to those from the R6 method. For shorter cracks, on the other hand, the proposed method reduces possible non-conservatism embedded in estimated J according to the R6 method, and the resulting predictions are slightly more conservative.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.3
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• pp.133-153
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• 2016

The objective of this study was to promote the use of collaborative digital reference service by identifying factors that affect user satisfaction and developing improvement measures based on the findings. Data were collected via a questionnaire administered to the users of the "Ask a Librarian" service and a survey to analyze the frequency and patterns of usage of the service. The survey analyzed the associations among subjects' demographic characteristics, information seeking patterns, factors that influence user recognition, service satisfaction, and follow-up intentions via responses to the questionnaire. Rapidity answers in factors of service satisfaction is found that the high impact of positive (+). According to the result of statistical analysis, the priority of service improvement strategies of digital reference service were suggested.

• Journal of Electrical Engineering and Technology
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• v.8 no.3
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• pp.507-515
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• 2013

This paper proposes a compensation method for the $2^{nd}$-order harmonic of single-phase grid-connected wind power generation systems. Theoretically, a single-phase grid-connected inverter system has no choice but to cause the $2^{nd}$-order harmonic to DC-link voltage. The reference active current is affected by the DC-link voltage. The output current from the reference active current is distorted by the $1^{st}$ and $3^{rd}$-order harmonic. The proposed method can compensate, conveniently, the reference active current with the $2^{nd}$-order harmonic. To reduce the $2^{nd}$-order ripple in the reference active current, proposed method takes a PR controller as a feed-forward compensator. PR controllers can implement selective harmonic compensation without excessive computational requirements; the use of these controllers simplifies the method. Both the simulation and experimental results agree well with the theoretical analysis.