• Proceedings of the Safety Management and Science Conference
• /
• 2006.04a
• /
• pp.147-156
• /
• 2006

Since IMF system was introduced once, downsizing has been usual phenomenon in business sphere. Downsizing influences the unemployed, and also the survivors such as in job stress, communication bias, lower organizational commitment and so on. This paper reviewed the relationship between organizational commitment and service quality, and the moderating effect of sex in hotel. Based on the responses from 494 hotel employees, the results of multiple regressional analysis showed that affective OC and normative OC have affirmative effects on service quality. The results of moderating analysis showed that continuance OC has an affirmative interactive-effect on responsiveness, assurance, and empathy with gender, and affective OC an negative interactive-effect on assurance.

• Journal of Labour Economics
• /
• v.31 no.2
• /
• pp.103-128
• /
• 2008

This paper estimates the union effect on the wages using Korean Labor and Income Panel Study by using fixed-effect estimation. While the cross-sectional estimates show the size of 4.6% increase in the wages of workers in the union compared 10 the observationally identical workers in the non-union jobs, the union wage effect is estimated as 2.1% increase in the panel study. This shows that there exits an substantial upward-bias in the cross-sectional estimation of union wage effect.

• Journal of Korea Technology Innovation Society
• /
• v.3 no.3
• /
• pp.36-52
• /
• 2000

This study takes an issue of efficiency analysis in the presence of network effect utilizing the DEA (Data Envelopment Analysis) framework. Network effect has important policy implication for the regulation of local monopolies which undertake their business through physical network, such as electricity, natural gas, local telephony, etc. If the difference in spatial condition between companies is not controlled properly, the performance comparison and associated incentive regulation bear significant bias. In this study, we propose a methodology to measure the true managerial or technical efficiency apart from efficiency difference accruing from the difference in spatial condition. A series of modified DEA efficiency models are combined to investigate the extent of exogenous and endogenous efficiency component in the Korean natural gas distribution companies. Empirical results show that the network effect plays significant role in determining superficial performance difference.

• Korean Journal of Adult Nursing
• /
• v.17 no.5
• /
• pp.783-792
• /
• 2005

Purpose: This study was conducted to meta-analyze the effects of hardiness on health-related variables. Method: After review of 19 studies performed by Korean nurses, research variables, statistical data(r or F), and other methodological data were extracted and coded. Research variables were categorized under 5 groups such as health-related behavior, well-being, adaptation, stress, and support according to conceptual similarity. Using SAS program, 20 research variables and 34 effect sizes were calculated after eliminating heterogeneous data by Q-test, Results: Effects of hardiness on whole research variables was .512 and ranged from .322 to .643 by categories. The greatest effect was obtained from well-being category, whereas the smallest effect from stress category. All effect sizes were statistically significant. But fail-safe numbers were small and failed to achieve reasonable tolerance level. Conclusion: Results of meta-analysis indicated that hardiness has a moderate effect on health-related variables. But for improving the reliability of the results by minimizing publication bias, the more hardiness studies should be done.

• Journal of the Korea Safety Management & Science
• /
• v.8 no.2
• /
• pp.129-138
• /
• 2006

Since IMF system was introduced once, downsizing has been usual phenomenon in business sphere. Downsizing influences the unemployed, and also the survivors such as in job stress, communication bias, lower organizational commitment and so on. This paper reviewed the relationship between organizational commitment and service quality, and the moderating effect of sex in hotel. Based on the responses from 494 hotel employees, the results of multiple regressional analysis showed that affective OC and normative OC have affirmative effects on service quality. The results of moderating analysis showed that continuance OC has an affirmative interactive-effect on responsiveness, assurance, and empathy with gender, and affective OC an negative interactive-effect on assurance.

• The Korean Journal of Emergency Medical Services
• /
• v.23 no.2
• /
• pp.33-42
• /
• 2019

Purpose: This study aimed to identify the effects of post-traumatic stress disorder intervention programs on firefighters through a meta-analysis. Methods: Seven studies were selected for meta-analysis. The overall average effect size, effect sizes for each intervention variables, and publication bias were analyzed using Comprehensive Meta-Analysis(CMA) version 2.0 (Biostat, Englewood, NJ, USA). Results: Post-traumatic stress disorder intervention programs were found to have a very low, not statistically significant effect (effect size=-.171, confidence interval=-0.361~0.019, Z=-1.768, p>.05). However, these programs was less than 50 (effect size=-.622). Conclusion: The results of this study suggest that further research on the effects of post-traumatic stress disorder intervention among firefighters is needed in order to develop more effective programs.

• International Journal of Highway Engineering
• /
• v.10 no.2
• /
• pp.47-55
• /
• 2008

In this paper, comparisons are presented on the predicted tensile strains which can affect the fatigue life of a thin asphalt concrete (AC) pavement near the surface of pavement from three-dimensional (3D) finite element (FE) using 3D measured tire contact stresses of a radial tire and a bias ply tire and a layered linear elastic program (BISAR). The objective was to analyze the stress distributions for a 11R22.5 radial tire and a $10{\times}20$ bias ply tire, and to compare the predicted tensile strains at the top and bottom of AC surface using different analysis methods. The results show that the stress distributions of two tires are similar but the 11R22.5 radial tire has much higher vertical contact stress than that of the $10{\times}20$ bias ply tire. The predicted tensile strains at the bottom of AC layer under the center of tire showed higher value by BM (BISAR with the measured contact area) method, which the measured tire contact area is used in a layered elastic program, while the tensile strain at the top of AC surface of 3.5cm offset distance from tire edge by 3D FE analysis showed the highest values among three analysis methods.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.19 no.8
• /
• pp.854-861
• /
• 2008

We have described a high power hybrid envelope elimination and restoration(H-EER) transmitter for IEEE 802.16e Mobile World Interoperability for Microwave Access(WiMAX) using an efficiency optimized power amplifier(PA). The PA has been designed to have maximum PAE at the important power generation $V_{ds}$, region using Nitronex 100-W PEP GaN HEMT. For the high power application, H-EER transmitter should be considered the regenerative oscillation problem due to the PA's bias fluctuation effect and bias modulator stability issue. Therefore, the bias modulator for H-EER transmitter has been designed to suppress the regenerative oscillation. For the interlock experiment, the bias modulator has been built with the efficiency of 72% and peak output voltage of 30 V for the envelope signal with a PAPR of 8.5 dB. The H-EER transmitter for WiMAX application has been achieved a high PAE characteristic, 38.8 % at an output power of 41.25 dBm. By using digital predistortion(DPD) technique, the Relative Constellation Error (RCE) has been satisfied the specification of -34.5 dB. This is the first work at 2.655 GHz high power H-EER transmitter for WiMAX application.

• Korean Journal of Remote Sensing
• /
• v.16 no.1
• /
• pp.13-24
• /
• 2000

SAR imagery usually reveals the influence of antenna look-direction on the delineation of geological structures. In this study, the look-direction bias in SAR image is quantitatively analyzed specifically for geological lineament study. Geologic lineaments are estimated using both Landsat TM and JERS-1 SAR images over the study area to quantitatively compare and analyze the look-direction bias in the SAR image. The standard geologic lineaments in the study area are established from lineaments estimated from TM images, field mapping, and fault lines in a published geologic map. The results show that lineaments normal to radar look-direction are extremely well enhanced while those parallel to look-direction are less visible as expected. However, certain lineaments even parallel to radar look-direction can still be detectable in a favorable topographic condition. Compared with TM image, the total number of detected lineaments in each direction in the SAR image increases or decreases ranging from 33% to 159% in length and from 28% to 187% in occurrence. The ratio of lineaments in SAR image to those in TM image with respect to direction can be fitted by a cosine function. The fitted function indicates that geological lineament is more easily detected in SAR image than in TM image within about $\pm$50$^{\circ}$ normal to radar look-direction. And lineaments with limited extension appear to be more sensitive to the look direction bias effect.

• Journal of Digital Convergence
• /
• v.20 no.1
• /
• pp.349-359
• /
• 2022

This research is a descriptive study that aimed to identify the health knowledge related stroke, optimistic bias, and social support of middle-aged adults and the effect these had on their health-promoting lifestyle This study was conducted by collecting 220 adults aged between 40 to 60 years from C City D city and K city. Data were analyzed using descriptive analysis, ANOVA, t-test, Pearson's correlation coefficients and multiple regression with the SPSS 23.0 program. The average health-promoting lifestyle was 44.27 points. The health-promoting lifestyle of the study participants showed a positive correlation between the optimistic bias(r=.18, p=.001) and social support(r= .61, p<.000). According to the results of multiple regression analysis, perception of Necessity for Stroke Education(β=.12, p=.010), optimistic bias(β=.18, p=.040), and social support(β=.48, p<.000) were shown to be significant factors that affected the health-promoting lifestyle of the participants. These variables explained 38.5%. Therefore, an health education program to improve the health-promoting lifestyle related to stroke in adults should be considered as a way to enhance social support and reduce optimistic bias.