• 한국정보시스템학회지:정보시스템연구
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• 제21권1호
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• pp.1-17
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• 2012

Common Method Bias(CMB) may cause the potential inflation of correlations between measures assessed via the same method. The problem of CMB has been well known in behavioral sciences because the survey method with self-reporting is vulnerable to CMB. Thus, the discussion on CMB is still ongoing in the MIS research in US. However, in Korea, the MIS research has never paid attention on the CMB problem. The purpose of this study is to examine the CMB problem in the Korean MIS research. To evaluate the effect of CMB, empirical studies on Technology Acceptance Model(TAM) are selected because (1) TAM is one of the MIS research areas studied intensively, (2) TAM is a theoretical model well supported by the existing empirical studies so that the result of this study would have a great ripple effect when the CMB problem turned out to be serious, (3) CMB is domain-specific. 47 TAM samples (out of 45 studies) from three Korean Journals were selected and the relevant data were collected such as correlation matrixes and the measures of the dependent variable. To find and evaluate the size of CMB, two analytic methods (Marker-Variable Technique and Method-Method Pair Technique) are employed. The result showed that there exists CMB in the Korean studies but the problem is not so serious to distort the empirical testing, compared with that of US studies. However, considering that CMB can contaminate the testing results, Korean MIS researchers should explicitly deal with the problem in designing empirical studies and collecting data.

• 한국표면공학회지
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• 제54권2호
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• pp.53-61
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• 2021

The properties of tetrahedral amorphous Carbon (ta-C) film can be determined by multiple parameters and comprehensive effects of those parameters during a deposition process with filtered cathodic vacuum arc (FCVA). In this study, Taguchi method was adopted to design the optimized FCVA deposition process of ta-C for improving deposition efficiency and mechanical properties of the deposited ta-C thin film. The influence and contribution of variables, such as arc current, substrate bias voltage, frequency, and duty cycle, on the properties of ta-C were investigated in terms of deposition efficiency and mechanical properties. It was revealed that the deposition rate was linearly increased following the increasing arc current (around 10 nm/min @ 60 A and 17 nm/min @ 100A). The hardness and I_D/I_G showed a correlation with substrate bias voltage (over 30 GPa @ 50 V and under 30 GPa @ 250 V). The scratch tests were conducted to specify the effect of each parameter on the resistance to plastic deformation of films. The analysis on variances showed that the arc current and substrate bias voltage were the most effective controlling parameters influencing properties of ta-C films. The optimized parameters were extracted for the target applications in various industrial fields.

• Communications for Statistical Applications and Methods
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• 제16권1호
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• pp.169-183
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• 2009

The simplicity and wide application of Greenberg et al. (1971) prompts to propose a set of alternative estimators of population total for multi-character surveys that elicit simultaneous information on many. sensitive study variables. The proposed estimators take into account the already known rough value of the correlation coefficient between Y(the characteristic under study) and p(the measure of size). These estimators are biased, but it is expected that the extent of bias will be smaller, since the proposed estimators are suitable for situations in between those optimum for the usual estimators and the estimators based on multi-characters for no correlation. The relative efficiency of the proposed estimators has been studied under a super population model through empirical study. It has been found through simulation study that a choice of an unrelated variable in the Greenberg et al. (1971) model could be made based on its correlation with the auxiliary variable used at estimation stage in multi-character surveys.

• 천문학회보
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• 제36권2호
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• pp.53.1-53.1
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• 2011

We analyze the halo and galaxy catalogs from the Millennium simulations at redshifts z=0, 0.5, 1 to determine the alignment profiles of cluster galaxies in terms of the matter density correlation coefficient and discuss a cosmological implication our result has for breaking parameter degeneracies. For each selected cluster, we measure the alignment between the major axes of the pseudo inertia tensors from all satellites within cluster's virial radius and from only those satellites within some smaller radius. Then we average the measured values over the similar-mass sample to determine the cluster galaxy alignment profile as a function of top-hat scale difference at each redshift. It is shown that the alignment profile of cluster galaxies is well approximated by a power-law of the nonlinear density correlation coefficient that is independent of the power spectrum normalization and bias factor. The alignment profile of cluster galaxies is found to have higher amplitude and lower power-law index when averaged over the larger-mass sample and to have rather weak redshift-dependence. This result is consistent with the picture that the satellite galaxies retain the memory of the external tidal fields right after merging and infalling into the clusters but they gradually lose the initial alignment tendency as the cluster's relaxation proceeds. Demonstrating that the nonlinear density correlation coefficient varies sensitively with the density parameter and neutrino mass fraction, we discuss a potential power of the cluster galaxy alignment profile as an independent probe of cosmology.

• Structural Engineering and Mechanics
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• 제37권3호
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• pp.331-349
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• 2011

This study investigates the use of a vibration correlation technique (VCT) to identify the buckling load of a rectangular thin plate. It is proposed that the buckling load can be determined experimentally using the natural frequencies of plates under tensile loading. A set of rectangular plates was tested for natural frequencies using an impact test method. Aluminum and stainless steel specimens with CCCC, CCCF and CFCF boundary conditions were included in the experiment. The measured buckling load was determined from the plot of the square of a measured natural frequency versus an in-plane load. The buckling loads from the measured vibration data match the numerical solutions very well. For specimens with well-defined boundary conditions, the average percentage difference between buckling loads from VCT and numerical solutions is -0.18% with a standard deviation of 5.05%. The proposed technique using vibration data in the tensile loading region has proven to be an accurate and reliable method which might be used to identify the buckling load of plates. Unlike other static methods, this correlation approach does not require drawing lines in the pre-buckling and post-buckling regions; thus, bias in data interpretation is avoided.

• 가정∙방문간호학회지
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• 제28권3호
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• pp.266-275
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• 2021

Purpose: This study was conducted to explore the mediating effect of menopausal symptoms in the relationship between occupational stress and quality of Life in middle-aged working women Method: Data collection was conducted from May 2019 to July 2019. A sample of 130 middle-aged working women was recruited from three cities in Korea. The collected data were analyzed using descriptive statistics, t-tset, ANOVA, Scheffé test, pearson correlation, and a three step regression analysis. The mediating effect was analyzed using PROCESS macro with a 95.0% bias corrected bootstrap confidence interval (5,000 bootstraps resampling). Results: Quality of life had a negative correlation with occupational stress and menopausal symptoms, while there was a positive correlation between occupational stress and menopausal symptoms. Menopausal symptoms showed a direct effect on quality of life through occupational stress as a mediating variable. Conclusion: These results suggest that menopausal symptoms should be considered when developing interventions to improve quality of life through occupational stress control of middle-aged working women

• 한국통신학회논문지
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• 제33권1C호
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• pp.86-93
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• 2008

Galileo 시스템은 통신 물리계층으로 직접수열/대역확산(direct sequence/spread spectrum, DS/SS) 시스템을 사용한다. DS/SS 시스템은 수신신호로부터 정보를 복원하기 위해 수신신호의 확산신호와 수신기에서 발생한 확산신호의 동기를 정확하게 결정하고, 유지해야 한다. 이를 위해 DS/SS 시스템은 획득과 추적 단계를 수행해 동기를 맞춘다. 이상적인 환경에서 최적 부호추적기는 EL-DLL이다(delay lock loop with early minus late discriminator). EL-DLL은 정확한 동기시점을 기준으로 확산신호의 상관함수가 정확히 대칭인 특징을 이용해 추적을 수행한다. 그러나 다중경로 신호가 수신되었을 때 상관함수의 대칭성이 왜곡되며, 이로 인해 추적이 완료되어 동기시점을 결정한 후에도 일정한 동기오차가 존재한다. 이처럼 추적기가 동기시점을 결정한 후에도 잔존하는 동기오차를 추적편이라 한다. 이상적인 환경에서 Galileo BOC(1,1) 신호로 변조된 확산신호는 정확한 동기시점에서 최고 값이 나타나며, 이 시점을 기준으로 반 칩(chip) 이른 상관시간 옵셋과 늦은 상관시간 옵셋에서 극소 값을 갖는다. 이때 다중경로신호는 항상 가시신호에 비해 늦게 수신되기 때문에 정확한 동기시점을 기준으로 반 칩 이른 상관 시간 옵셋 주변의 상관 값은 다중경로신호에 의해 크게 왜곡되지 않는 특징을 갖는다. 본 논문은 이 특징을 바탕으로 Galileo BOC(1,1)에 알맞은 추적편이 완화기법을 제안하고, 기존 기법과 제안한 기법의 추적편이 특성을 분석한다.

• 한국지구과학회지
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• 제36권4호
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• pp.330-340
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• 2015

본 연구에서는 CCD 카메라가 장착된 Skyviewer로부터 촬영된 하늘 영상 자료를 이용하여 전운량을 산출하는 알고리즘을 개발하였다. 전운량 산출은 RGB 영상 내의 차폐 영역을 제거하고 GBR 빈도분포에 따른 영상을 분류하며, RBR 경계값을 결정하여 구름 화소를 분류한다. 분류된 구름 화소에서 태양광 영역을 제거한 후 유효성 검사를 통해 전운량을 산출하게 된다. 전운량 산출 알고리즘의 정확성을 검증하기 위하여 관측소와 가장 가까운 강원지방기상청의 목측 전운량 자료와 편이(Bias), 평균제곱근오차(RMSE), 상관계수를 분석하였다. 선정된 사례는 계절별 일 사례로 8시부터 17시까지의 정시 자료를 사용하였다. 분석 결과 Skyviewer로부터 산출된 전운량의 편이는 평균적으로 -0.8할의 차이를 보였으며, 평균제곱근오차는 1.6할로 전운량의 차이가 2할 내에서 나타나고 있었다. 또한, 두 관측소는 떨어진 거리의 차이가 있음(약 4 km)에도 불구하고 상관계수가 모든 사례에서 평균 0.91 이상으로 매우 높았다.

• 가정과삶의질연구
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• 제33권3호
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• pp.15-29
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• 2015

The purpose of this study was to explore ethnic socialization enacted by Japanese marriage migrant women currently raising 7- to 18-year-old children in Korea. To accomplish this goal, we examined the following research questions: (1) What is the level of ethnic socialization enacted by Japanese marriage migrant mothers? (2) Does the level of ethnic socialization vary by demographic and ethnocultural factors? (3) To what extent do demographic and ethnocultural factors influence the enactment of ethnic socialization by Japanese marriage migrant mothers? The sample consisted of 243 Japanese marriage migrant women currently raising 7- to 18-year-old children in Korea. For data analysis, T-test, correlation, ANOVA, and hierarchical regression analyses were used. Also, we performed separate analyses for two subtypes of ethnic socialization in particular, namely cultural socialization and preparation for bias. Ethnocultural factors examined in this study were the level of discrimination experience, Japanese ethnic identity, and husbands' ethnic orientation in childrearing. The main results of this study were as follows. First, results showed that Japanese marriage migrant women enacted moderate levels of cultural socialization and preparation for bias. Second, Japanese marriage migrant women's cultural socialization and preparation for bias were both positively related to the levels of women's discrimination experience and Japanese ethnic identity. Also, the younger the age of the firstborn child, the more preparation for bias these women performed. In addition, women whose Korean husbands wanted to raise their children more biculturally performed more cultural socialization compared to those with Korean husbands who wanted to raise their children as Korean. Third, hierarchical regression analyses revealed that women's discrimination experience and ethnic identity positively predicted both types of ethnic socialization. Also, Korean husband's bicultural orientation towards childrearing predicted a higher level of cultural socialization by Japanese marriage migrant women. Results of this study provide basic information about ethnic socialization among multicultural families in Korea, which can be useful for promoting positive self-identity among multicultural children. Furthermore, the results suggest that husbands' support and cooperation in ethnic socialization can be crucial for marriage migrant women to socialize their children utilizing their cultural and experiential resources.

• 한국심리학회지:법
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• 제12권1호
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• pp.35-51
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• 2021

자유의지에 대한 믿음은 인간 행동의 원인과 행위에 따른 책임을 판단하는데 필요한 개념으로서 신경과학, 철학, 윤리학, 형법 등 다양한 학문 분야에서 자유의지의 개념에 대한 논쟁이 이어지고 있다. 자유의지와 결정론척도((FAD-Plus; Paulhus & Carey, 2011)는 개인의 자유의지에 대한 믿음과 관련된 구성요소를 측정하는 검사도구로, 영미권을 중심으로 개발되어 최근 국내에도 번역 소개되었다. 본 연구는 기존의 탐색적 요인분석을 실시한 선행연구에서 나아가 다양한 연령대와 사회경제적 배경을 가진 1000명의 일반인을 대상으로 확인적 요인분석을 실시하였다(연구 1). 모형의 적합성, 집중타당도, 판별타당도를 통하여 해당 척도의 신뢰성과 타당성을 확보하였다. 이후, FAD-Plus 척도의 하위문항인 '자유의지에 대한 믿음'이 귀인편향 및 통제소재와 어떠한 관계를 보이는지 살펴보았다(연구 2). 총 83명의 피험자들을 대상으로 분석을 실시한 결과 자유의지에 대한 높은 믿음은 부정적 행위에 대한 처벌판단, 내부귀인과 정적인 상관을 보였으나 긍정적 행위에 대한 보상판단에서는 유의한 관계를 보이지 않았다. 이를 통해 기존에 한국판으로 번안된 FAD-Plus 척도가 일반인들을 대상으로도 타당함을 검증하였으며, 자유의지에 대한 믿음, 귀인편향, 통제소재, 행위판단과의 관계를 살펴볼 수 있었다. 본 연구의 한계, 정책적 함의, 그리고 향후 연구 방향에 대해 논의하였다.