• Journal of the Korean Society for Nondestructive Testing
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• v.12 no.1
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• pp.9-15
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• 1992

Ultrasonic spectroscopy is likely to become a very powerful NDE method for detection of microfects and thickness measurement of thin film below the limit of ultrasonic distance resolution in the opaque materials, provides a useful information that cannot be obtained by a conventional ultrasonic measuring system. In this paper, we considered a thin film below the limit of ultrasonic distance resolution sandwitched between two substances as acoustical analysis model, demonstrated the usefulness of ultrasonic spectroscopic analysis technique using information of ultrasonic frequency for measurements of thin film thickness, regardless of interference phenomenon and phase reversion of ultrasonic waveform. By using frequency intervals(${\triangle}f$) of periodic minima from the ratio of reference power spectrum of reflective waveform obtained a sample to power spectrum of multiple reflective waves obtained interference phenomenon caused by ultrasonic waves reflected at the upper and lower surfaces of a thin layer, can measured even dimensions of interest are smaller than the ultrasonic wave length with simplicity and accuracy.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.1
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• pp.17-24
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• 2015

Mixed acceptance sampling plans for quantity of products in prepackages are widely used for compliance testing. To pass testing, random samples jointly comply with two legal requirements: (i) the average net content of an inspection lot shall be not less than the labelled quantity and (ii) the numbers of under-filled prepackages in a sample are less than or equal to permitted numbers. This paper discusses some drawbacks of the acceptance sampling plans and requirements recommended in OIML R87 (KS A 50087 translated by Korean) developed by the International Organization of Legal Metrology and evaluates the producer's and consumer's risks. In addition, problem of determining a target value in filling processes of prepackages under the OIML R87 requirements is addressed and illustrated with a numerical example.

• Communications for Statistical Applications and Methods
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• v.29 no.3
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• pp.301-317
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• 2022

In this paper, we propose a change point detection procedure based on the modified information criterion in a generalized lambda distribution (GLD) model. Simulations are conducted to obtain empirical critical values of the proposed test statistic. We have also conducted simulations to evaluate the performance of the proposed methods comparing to the log-likelihood method in terms of power, coverage probability, and confidence sets. Our results indicate that, under various conditions, the proposed method modified information criterion (MIC) approach shows good finite sample properties. Furthermore, we propose a new goodness-of-fit testing procedure based on the energy distance to evaluate the asymptotic null distribution of our test statistic. Two real data applications are provided to illustrate the use of the proposed method.

• Journal of the Korea Safety Management & Science
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• v.12 no.2
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• pp.217-223
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• 2010

The research proposes the complementary methodology using integrated hypothesis testing and confidence interval models that can be identified the statistical difference and practical equivalence. The models developed in this study can be used in the quality improvement processes such as QC story 15 steps. For the expressions of CI4LSD(Confidence Interval for Least Significant Difference) and CI4TOST(Confidence Interval for Two One-Sided Tests) are simple, quality practioners can efficiently handle them. CI4TOST models as a complement can be applied when CI4LSD models are influenced by sample size and precision.

• Journal of the Korean Data and Information Science Society
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• v.11 no.1
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• pp.83-90
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• 2000

The chi-squared test statistic is usually employed for testing independence of two categorical variables in a two-way contingency table. It is well known that, under independence, the test statistic has an asymptotic chi-squared distribution under multinomial or product-multinomial models. For the case where both margins fixed, the sampling model of the contingency table is a multiple hypergeometric distribution and the chi-squared test statistic follows the same limiting distribution. In this paper, we study the difference between the small sample and large sample distributions of the chi-squared test statistic for the case with fixed margins. For a few small sample cases, the exact small sample distribution of the test statistic is directly computed. For a few large sample sizes, the small sample distribution of the statistic is generated via a Monte Carlo algorithm, and then is compared with the large sample distribution via chi-squared probability plots and Kolmogorov-Smirnov tests.

• CELLMED
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• v.11 no.4
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• pp.18.1-18.8
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• 2021

Jawarishe Jalinoos (JJ) is an orally used formulation available in semisolid dosage form, prepared with powdered plant materials mixed in honey or sugar syrup. It has many admirable pharmacological effects and used in Unani medicine to treat various acute and chronic disorders since ancient times. The ICH Harmonised Tripartite Guideline stated that photostability testing should be an essential part of stability testing to confirm that light exposure does not result in an unacceptable change in drugs substance and finished products. To date, the effect of light on JJ is not studied, in this study photostability evaluation of JJ was carried out. The test sample was manufactured with genuine ingredients in the in-door pharmacy of the National Institute of Unani Medicine. JJ was packed in two transparent polyethylene terephthalate airtight containers. The first sample was analysed at zero-day and the second sample was placed in a stability chamber subjected to light challenge with an overall illumination of 1.2 million lux hours combined with near ultraviolet energy of 200-watt hours per square meter by using option 2, along with 30±2℃ temperature and relative humidity 70±5%. Analysis of both finished products showed no considerable changes in organoleptic characters. Less than 5% variation was observed in physicochemical parameters. HPTLC fingerprinting showed justifiable variation. Microbial load and specific counts were within the limit prescribed by WHO. As no unacceptable changes were noted in JJ subjecting to light challenge, it is concluded that JJ is a photostable Unani compound formulation.

• Journal of Power Electronics
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• v.8 no.3
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• pp.217-227
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• 2008

The electric power subsystems (EPS) of most remote sensing satellites consist of a solar array as a source of energy, a storage battery, a power management and control (PMC) unit and a charge equalization unit (CEU) for the storage battery. The PMC and CEU use high frequency transformers in their power modules. This paper presents a design, implementation and testing results of a high frequency transformer for the EPS of satellite applications. Two approaches are used in the design process of the transformer based on the pre-determined transformer specifications. The transformer is designed based on an ETD 29 ferrite core. The implemented transformer consists of one center-tapped primary coil with eleven center-tapped secondary coils. The offline calculation results and measured values of R, L for transformer coils are convergence. A test circuit for measuring the transformer parameters like voltage, current and B-H hysteresis was implemented and applied. The test results confirm that the voltage waveforms of both primary and secondary coils were as desired. No overlapping occurred between the control signal and the transformer, which was not saturated during testing even during a short circuit test of the secondary channels. The dynamic B-H loop characteristics of the used transformer cores were measured. The sample test results are given in this paper.

• Tribology and Lubricants
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• v.25 no.3
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• pp.163-170
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• 2009

We developed a compact micro indentation testing device (designated SNUT) which is capable to measure Young's modulus of a sample using depth and applied load data during indentation. Performance of this device was evaluated using pure Ti, pure Ni, and die steel (SKD11). As a result of analysing the indentation test data, the frame compliance $C_f$ was found to influence mainly the modulus by 80% among several factors affecting accuracy of Young's modulus. Project area, which was determined by indirect indentation method, was modified using direct SEM observation. Finally, Young's modulus error was reduced to 5% after taking into consideration the frame compliance and modified projected area from 80% error without any these two correction factors. The performance of SNUT and MTS instruments was compared using same specimen (pure Ti).

• Journal of Pharmaceutical Investigation
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• v.2 no.1
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• pp.5-13
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• 1972

There are some repels in which they studied on the change of acid-consuming capacity of aluminium hydroxide resulted from the passing of time. However, the relationship between grain sizes(particle sizes) and the acid-consuming capacity of dried aluminium hydroxide gel was not been studied. And studies on the grain sizes of aluminium hydroxide gel qualified by pharmacopoeia of Korea has not been reported. For the purpose of studying these two problems, the author prepared two-kinds of aluminium hydroxide gel as follows : $Na_2OAl_2O_3+CO_2------{\longrightarrow}Al(OH)_3{\cdots}{\cdots}{\cdots}$sample 1 $Al_2(SO_4)_318H_2O+6NaHCO_3{\longrightarrow}Al(OH)_3{\cdots}{\cdots}{\cdots}$sample 2 Both of sample 1 and 2 are found to be amorphous by X-ray diffraction methods, and their acid-consuming capacities were determined by the method of pharmacopeia of Korea. The grain size was measured by X-ray diffraction method, the particle sizes observed by electron microscopy, and the change of acid-consuming capacity with passing of time was determined by the method of pharmacopoeia of Korea. The results of these studies are summerized as follows: 1. The grain size was linearly enlarged as the time goes by. The aluminium hydroxide gel gradually crystallized in a certain period of time. 2. The acid-consuming capacity was in exponential function, decreased as the grain size of them enlarged. 3. One particle consists of tens of grains.4. Grinding the Sample obtained in any period of testing time in mortar did not change both their grain size and their acid-consuming capacity. 5. The grain size of dried aluminium hydroxide gel ought to be micronized less than $100{\AA}$ for maintaining the ability such as consumes 250m1 of 0. 1N-HC1 solution per Is of $Al(OH)_3$ described in pharmacopoeia of Korea.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.3
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• pp.124-127
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• 2012

Syphilis is an infectious and sexually transmitted chronic disease caused by Treponema pallidum. On the basis of clinical findings, the disease has been divided into a series of overlapping stages, which are used to help guide treatment and follow-up. Persons who have syphilis might seek treatment for signs or symptoms of primary infection, secondary infection and tertiary infection. Latent infections are detected by serologic testing. A presumptive diagnosis of syphilis is possible with the use of two types of serologic tests: nontreponemal tests and treponemal tests assay. The use of only one type of serologic test is insufficient for diagnosis, because each type of test has limitations, including the possibility of false-positive test results in persons without syphilis. KFDA published Koreans guideline of Sexually transmitted infections in 2011. Two hundred samples were tested by RPR card test and Mediace RPR test with simultaneously. The agreement between RPR card test and Mediace RPR test was 95%, the discrepant samples was 5%. The characteristics of 10 discrepant samples was RPR card Positive and Mediace RPR negative nine samples, RPR card negative and Mediace RPR positive one sample. The nine samples were confirmed as FTA-ABS by KFDA guideline of syphilis test algorism, all IgM test was Negative, all IgG test was reactive. So, these cases were past or latent syphilis. The one sample was false-positive reaction.