• The Journal of Information Systems
• /
• v.21 no.1
• /
• pp.1-17
• /
• 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.

• Journal of the Korea Convergence Society
• /
• v.13 no.1
• /
• pp.1-12
• /
• 2022

In this study, the effect of VR exposure programs integrated with web-based cognitive restructuring education on reducing social anxiety was confirmed. The experimental group (n=12) received a 10~15 minute session of web-based cognitive intervention and a 20-minute session of virtual reality exposure therapy. The comparison group (n=15) received a 10~15 minute session of web-based speech education and a 20-minute session of virtual reality exposure therapy. After 4 weeks, the experimental group had an increase in positive interpretation bias, a decrease in negative interpretation bias, and a decreased level of social anxiety. These results suggest that the combination of self-help form of web-based cognitive intervention in the treatment of social anxiety disorder can improve the therapeutic effect of VRET.

• 한국노년학
• /
• v.37 no.4
• /
• pp.871-891
• /
• 2017

The purpose of this paper is to reduce the reverse-causality and overestimate bias of analysis on how health affected middle-aged and elderly worker's early retirement. From the Korean Longitudinal Study of Ageing(KLoSA) panel data, I researched 1,049 people who were 45-52 years old in 2006. To eliminate the reverse-causality problem, I used the health data which is surveyed before retirement. To reduce bias, I controlled the health status when retirees worked. The main results are as follows. First, the worsened health still affects the hazard of early retirement, with reducing the endogeneity problem. Second, chronic illness is one of the strong predictors of early retirement to self-employed, and self-reported bad health is the main health predictor of wage workers. These results give two implications; first, the impact magnitude of the health indicator depends on employment type. Each employment type has different flexibility of working hours. It seems that the flexibility can reduce early retirement hazard with health problems. Self-employed, who has more flexibility of working hours can work until they have to stop working due to the serious health problem or doctor's advice. Second, to promote middle-aged and elderly workers to keep working, the long-term health policy which decreases chronic illness is needed.

• Proceedings of the KIEE Conference
• /
• 1995.07c
• /
• pp.1085-1087
• /
• 1995

A large leakage current may be one of the critical issues for poly-silicon thin film transistors(poly-Si TFTs) for LCD applications. In order to reduce the leakage current of poly-Si TFTs, several offset gated structures have been reported. However, those devices, where the offset length in the source region is not same as that in the drain region, exhibit the asymmetric electrical performances such as the threshold voltage shift and the variation of the subthreshold slope. The different offset length is caused by the additional mask step for the conventional offset structures. Also the self-aligned implantation may not be applicable due to the mis-alignment problem. In this paper, we propose a new fabrication method for poly-Si TFTs with a self-aligned offset gated structure by employing a photo resistor reflow process. Compared with the conventional poly-Si TFTs, the device is consist of two gate electrodes, of which one is the entitled main gate where the gate bias is employed and the other is the entitled subgate which is separate from both sides of the main gate. The poly-Si channel layer below the offset oxide is protected from the injected ion impurities for the source/drain implantation and acts as an offset region of the proposed device. The key feature of our new device is the offset lesion due to the offset oxide. Our experimental results show that the offset region, due to the photo resistor reflow process, has been successfully obtained in order to fabricate the offset gated poly-Si TFTs. The advantages of the proposed device are that the offset length in the source region is the same as that in the drain region because of the self-aligned implantation and the proposed device does not require any additional mask process step.

• Atmosphere
• /
• v.27 no.4
• /
• pp.467-481
• /
• 2017

A correction method of reflectivity in partial beam blockage (PBB) area is suggested, which is based on the combination of digital terrain information and self-consistency principle between polarimetric observation. First, the reflectivity was corrected by adding the radar energy loss estimated from beam blockage simulation using digital elevation model (DEM) and beam propagation geometry in standard atmosphere. The additional energy loss by unexpected obstacles and non-standard beam propagation was estimated by using the coefficient between accumulated reflectivity ($Z_H$) and differences of differential phase shift (${\Phi}_{DP}$) along radial direction. The proposed method was applied to operational S-band dual-polarization radar at Jindo and its performance was compared with those of simulation method and self-consistency method for six rainfall cases. When the accumulated reflectivity and increment of ${\Phi}_{DP}$ along radial direction are too small, the self-consistency method has failed to correct the reflectivity while the combined method has corrected the reflectivity bias reasonably. The correction based on beam simulation showed the underestimation. For evaluation of rainfall estimation, the FBs (FRMSEs) of simulation method and self-consistency principle were -0.32 (0.59) and -0.30 (0.57), respectively. The proposed method showed the lowest FB (-0.24) and FRMSE (0.50). The FB and FMSE were improved by about 18% and by 19% in comparison to those before correction (-0.42 and 0.70). We can conclude that the proposed method can improve the accuracy of rainfall estimation in PBB area.

• Journal of Preventive Medicine and Public Health
• /
• v.31 no.1 s.60
• /
• pp.49-58
• /
• 1998

The study was done to determine the reliability and validity of a life style questionnaire for the elderly. The questionnaires were sent to 16,524 elderly people who were beneficiaries of Korean Medical Insurance Corporation in Pusan. Among the completed 9,139 questionnaires, 200 were randomly sampled and retested. finally, 110 duplicates were collected. Weighted kappa-value and Pearson correlation coefficients were estimated to measure the reliability. Validity coefficient was estimated by using reliability coefficient. In self-self responses, reliability coefficients of the most of items were over 0.6 except some physical activity related item. Relatively high reliability was observed in smoking, alcohol related items and anthropometric items. In self-proxy responses, most of the physical activity related items were found to be less reliable than self-self responses. Smoking and alcohol related items were consistently reliable. Male showed higher validity in food related item than female. On the other hand, some of the physical activity related items and smoking and alcohol related items were less valid in male than female. With regard to bias of proxy respondents, offsprings tended to underestimate the frequency of house cleaning' and 'kitchen work' and overestimate the height of them. In conclusion, the life style questionnaire was found to be reliable in the most of items. But, some items related with physical activity were found to be somewhat less reliable. Sexual difference on the validity was identified in some items. With regard to bias of proxy respondents, offsprings tended to have bias in part of items of housework and anthropometry.

• The Korean Journal of Applied Statistics
• /
• v.33 no.2
• /
• pp.203-213
• /
• 2020

The self-controlled case series (SCCS) study measures the relative risk of exposure to exposure period by setting the non-exposure period of the patient as the control period without a separate control group. This method minimizes the bias that occurs when selecting a control group and is often used to measure the risk of adverse events after taking a drug. This study used SCCS to examine the increased risk of side effects when two or more drugs are used in combination. A conditional Poisson model is assumed and analyzed for drug interaction between the narcotic analgesic, tramadol and multi-frequency combination drugs. Bayesian inference is used to solve the overfitting problem of MLE and the normal or Laplace prior distributions are used to measure the sensitivity of the prior distribution.

• Journal of Families and Better Life
• /
• v.33 no.3
• /
• pp.15-29
• /
• 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.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.2
• /
• pp.559-564
• /
• 2015

Background: The participation of women in cervical cancer screening in Malaysia is low. Self-sampling might be able to overcome this problem. The aim of this study was to assess the reliability of self-sampling for cervical smear in our country. Materials and Methods: This cross-sectional study was conducted on 258 community dwelling women from urban and rural settings who participated in health campaigns. In order to reduce the sampling bias, half of the study population performed the self-sampling prior to the physician sampling while the other half performed the self-sampling after the physician sampling, randomly. Acquired samples were assessed for cytological changes as well as HPV DNA detection. Results: The mean age of the subjects was $40.4{\pm}11.3years$. The prevalence of abnormal cervical changes was 2.7%. High risk and low risk HPV genotypes were found in 4.0% and 2.7% of the subjects, respectively. A substantial agreement was observed between self-sampling and the physician obtained sampling in cytological diagnosis (k=0.62, 95%CI=0.50, 0.74), micro-organism detection (k=0.77, 95%CI=0.66, 0.88) and detection of hormonal status (k=0.75, 95%CI=0.65, 0.85) as well as detection of high risk (k=0.77, 95%CI=0.4, 0.98) and low risk (K=0.77, 95%CI=0.50, 0.92) HPV. Menopausal state was found to be related with 8.39 times more adequate cell specimens for cytology but 0.13 times less adequate cell specimens for virological assessment. Conclusions: This study revealed that self-sampling has a good agreement with physician sampling in detecting HPV genotypes. Self-sampling can serve as a tool in HPV screening while it may be useful in detecting cytological abnormalities in Malaysia.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.2182-2186
• /
• 2003

This paper presents the differential type resonant accelerometer (DRXL) and its performance test results. The DRXL is the INS grade, surface micro-machined sensor. The proposed DRXL device produces a differential digital output upon an applied acceleration, and the principle is a gap-dependent electrical stiffness variation of the electrostatic resonator with torsion beam structures. Using this new operating concept, we designed, fabricated and tested the proposed device. The final device was fabricated by using the wafer level vacuum packaging process. To test the performance of the DRXL, a nonlinear self-oscillation loop is designed using describing function technique. The oscillation loop is implemented using discrete electronic elements. The performance test of the DRXL shows that the sensitivity of the accelerometer is 12 Hz/g and its long term bias stability is about $2mg(1{\sigma})$. The turn on repeatability, bandwidth, and dynamic range are 4.38 mg, 100 Hz, and ${\pm}\;70g$, respectively.