• 천문학회보
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• 제37권1호
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• pp.58.1-58.1
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• 2012

We present a comprehensive re-analysis of stellar photometric variability in the field of open cluster M37, using our new high-precision light curves. This dataset provides a rare opportunity to explore different types of variability between short (-minutes) and long (-one month) time-scales. To investigate the variability properties of -30,000 objects, we developed new algorithms for detecting periodic, aperiodic, and sporadic variability in their light curves. About 7.5% (2,284) of the total sample exhibits convincing variations that are induced by flares, pulsations, eclipses, starspots and, in some cases, unknown causes. The benefits of our new photometry and analysis package are evident. The discovery rate of new variables is increased by 63% in comparison with the existing catalog of variables, and 51 previously identified variables were found to be false positives resulting from time-dependent systematic effects. Based on extended and improved catalog of variables, we will review the basic properties (e.g., periodicity, amplitude, type) of the variability and how different they are for different spectral types and for cluster memberships.

• 천문학회보
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• 제42권2호
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• pp.78.3-78.3
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• 2017

The positions of galaxies in comoving Cartesian space varies under different cosmological parameter choices, inducing a redshift-dependent scaling in the galaxy distribution. The shape of the two-point correlation of galaxies exhibits a significant redshift evolution when the galaxy sample is analyzed under a cosmology differing from the true, simulated one. In our previous works, we can made use of this geometrical distortion to constrain the values of cosmological parameters governing the expansion history of the universe. This current work is a continuation of our previous works as a strategy to constrain cosmological parameters using redshift-invariant physical quantities. We now aim to understand the redshift evolution of the full shape of the small scale, anisotropic galaxy clustering and give a firmer theoretical footing to our previous works.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.774-779
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• 2003

Arc-shaped line array slits have been used for the laser generation of focused Lamb waves. The spatially expanded Nd:YAG pulse laser was illuminated through the arc-shaped line array slit on the surface of a sample plate to generate the Lamb waves of the same pattern as the slit. Then the generated Lamb waves were focused at the point of which distance from the slit position is dependent on the curvature of slit arc. The proposed method showed better spatial resolution than the conventional linear array slit in the detection of laser machined linear defect and drill machined circular defect on aluminum plates of 1mm thickness.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.116-116
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• 2003

In 1998, Osada and co-workers isolated 140 mg of a novel cytokine modulator from 18 L of the culture broth of Streptomyces RK95- 31 isolated from a soil sample in Hiroshima Prefecture. This new immunosuppressant was named (-)-cytoxazone and its absolute configuration was determined on the basis of its NMR, CD and X -ray analysis. It interferes with cytokine IL4, IL10 and IgG production by selective inhibition of the signaling pathway of Th2 cells, but not Thl cells. Inhibitors of Th2-dependent cytokine production have potential as potent chemotherapeutic agents in the field of immunotherapy. The (-)-cytoxazone is different from known immunomodulators such as FK 506 and rapamycin in respect of structure and biological activity. As such cytoxazone should be a useful tool for understanding signaling pathways in Th2 cells, the synthesis of (-)-cytoxazone is of interest for the development of new cytokine modulators.

• 대한가정학회지
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• 제37권2호
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• pp.85-98
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• 1999

The purpose of this study is to identify the preferences for care type among the elderly and to analyze contributing variables. The sample in this study are 485 elder people who are age 55 and over. The independent variables are divided into five factors according to their characteristics, and the dependent variables fall into two categories of private and public care types. The descriptive statistics and Logistic Regression method are employed for the analysis. The results can be summarized as follows. The elderly prefer individual care paid for by their own support to the other types like the care by children or institution. However, the elderly stiff like and expect family care by their children. The variables that haute affected the preferences of the care types among the elderly are whether they are employed or not, household's the amount of debt, whether they currently live with the oldest child, their level of self esteem and their degree of satisfaction in life. The results show that the elderly don't have various wants or alternatives to their care and regard public care as negative support for the financially incapable or the elderly who have no relatives.

• Asian Journal of Business Environment
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• 제5권2호
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• pp.31-36
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• 2015

Purpose - This work aims to study the existing management process and methods of statistical evaluation of personnel mobility management, and propose improvement measures. This is particularly relevant in today's market economy because proper organization of personnel movement affects the availability and effective utilization of human resources in enterprises. Hence, it influences the volume, timely execution of work, equipment efficiency, and consequently the volume of production, its cost, profit, and other economic indicators. Research design, data, and methodology - We investigate the indicators that measure staff mobility, and their dependent consequences. Further, it analyses the factors influencing high staff turnover, which is a main indicator of staff mobility. Results - Measures for staff mobility development and prevention of turnover are proposed. Micom Systems is a sample case that has developed special programs to reduce staff turnover. Conclusions - Staff mobility leads to additional costs, significant loss of working time, and increase in defects. However, the advantages of staff mobility outweigh these negative factors. The role of staff mobility in a market economy cannot be overestimated.

• 복식문화연구
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• 제16권6호
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• pp.1126-1141
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• 2008

The purposes of this study identify how attributes of the website impact on consumer attitude toward the website. For this purpose, the study tested covariance structural model which set relationships among independent variables (interactivity and shopping value), meditated variables(relationship commitment), and dependent variables(attitude toward website). The data were collected from a sample of 239 internet shopper of college female students. The covariance structural model and research hypothesis analyzed by using SPSS 16.0 and AMOS 5.0 program. The results are as follows: First, the structural model is accepted significantly. Second, interactivity and shopping value of website have a positive influence on relationship commitment. Third, interactivity, shopping value of website, and relationship commitment have a positive impact on attitude toward the website. Forth, even if shopping value has not a positive influence on attitude toward the website, it was found to have a significant effect on attitude toward the website through the relationship commitment.

• 대한간호학회지
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• 제43권2호
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• pp.154-164
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• 2013

Purpose: The purpose of this article is twofold: 1) introducing logistic regression (LR), a multivariable method for modeling the relationship between multiple independent variables and a categorical dependent variable, and 2) examining use and reporting of LR in the nursing literature. Methods: Text books on LR and research articles employing LR as main statistical analysis were reviewed. Twenty-three articles published between 2010 and 2011 in the Journal of Korean Academy of Nursing were analyzed for proper use and reporting of LR models. Results: Logistic regression from basic concepts such as odds, odds ratio, logit transformation and logistic curve, assumption, fitting, reporting and interpreting to cautions were presented. Substantial shortcomings were found in both use of LR and reporting of results. For many studies, sample size was not sufficiently large to call into question the accuracy of the regression model. Additionally, only one study reported validation analysis. Conclusion: Nursing researchers need to pay greater attention to guidelines concerning the use and reporting of LR models.

• Journal of applied mathematics & informatics
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• 제18권1_2호
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• pp.247-259
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• 2005

Necessary and sufficient conditions, under which there exists (at least) a sequence of vectors of real numbers for which the distribution function (d.f.) of any vector of extreme order statistics converges to a non-degenerate limit, are derived. The interesting thing is that these conditions solely depend on the univariate marginals. Moreover, the limit splits into the product of the limit univariate marginals if all the bivariate marginals of the trivariate d.f., from which the sample is drawn, is of negative quadrant dependent random variables (r.v.'s). Finally, all these results are stated for the multivariate extremes with arbitrary dimensions.

• 한국전기전자재료학회논문지
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• 제14권3호
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• pp.202-206
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• 2001

Using THz time-domain spectroscopy (THz-TDS), the power absorption, the index of refraction, and the real conductivity of silica sand are measured from 0.1[Thz] to 0.5[Thz] frequency range. It is impossible to measure the characterization of the silica sand by simple electrical measurements using mechanical contacts, e.g., Hall effect or four-point probe measurements. However, the THz-TDS technique can measure not only electrical but also optical characterization of he sample. Also this technique can measure frequency dependent results. Especially, the real conductivity was increased according to THz frequency. This is unusual material compare with metal and semiconductor materials; the measured real conductivity are not followed by the simple Drude theory.