• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.09a
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• pp.46-58
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• 1995

Although numerous distributed database design models and solution algorithms have been developed, very few have been validated. Validation is critical to the successful application of such models to distributed database design. In this paper, we develop a simulation system for distributed database design. We then analyze and validate an average response time model using simulation. The simulation results demonstrate that the average response time model is reasonably accurate.

• Journal of Korean Society for Quality Management
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• v.16 no.1
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• pp.49-58
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• 1988

When a question in a sample survey is sensitive or highly personal, respondents may prefer not to give truthful answers. To eliminate the resulting evasive answer bias Warner suggested a randomized response model. In this paper, a modification of Warner's method is presented and compared with Warner's method. The relation between this modified method and an unrelated question method is also discussed.

• Journal of Korean Society for Quality Management
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• v.23 no.2
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• pp.68-79
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• 1995

Good estimation of the slopes of the mixture response function may be important as well as estimation of mean mixture response. It is possible to evaluate and compare several mixture designs with respect to the slope. A graphical method is proposed that allows us to evaluate a given design's support for the fitted model in terms of slope variance. We can plot variances of slopes along Cox direction according to existence of restriction of simplex region when comparing several different mixture designs.

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.789-795
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• 2014

In a demand response (DR) market run by independent system operators (ISOs), load aggregators are important market participants who aggregate small retail customers through various DR programs. A load aggregator can minimize the allocation cost by efficiently allocating its demand response resources (DRRs) considering retail customers' characteristics. However, the uncertain response behaviors of retail customers can influence the allocation strategy of its DRRs, increasing the economic risk of DRR allocation. This paper presents a risk-based DRR allocation method for the load aggregator that takes into account not only the physical characteristics of retail customers but also the risk due to the associated response uncertainties. In the paper, a conditional value-at-risk (CVaR) is applied to deal with the risk due to response uncertainties. Numerical results are presented to illustrate the effectiveness of the proposed method.

• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.123-129
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• 2013

Among various manual materials handling tasks, pushing/pulling was known to be one of the risk factors for the low back and shoulder musculoskeletal disorders (MSDs). This study was conducted to find out an optimal solution set of the handle height and distance for 4-wheel cart with two vertical handles. Ten male college students participated in the pushing force measurement experiment. The face-centered cube design, one of the central composite designs, was applied for the experiment, and the isometric voluntary pushing force was measured in 9 treatment conditions. The second order response surface model was predicted by using the pushing strength as a response variable, and the handle height and distance as independent factors. According to the 2nd order response model, the handle height and distance showed nonlinear relationship with the isometric pushing strength. To maximize the 2nd order response model (pushing force), the handle height and distance were optimized. The optimal handle height was 'xyphoid process height - stature', and the optimal handle distance was '$1.25{\times}shoulder$ width'. When calculated using the anthropometric data of the subjects of this study, the optimal handle height was $115.4{\pm}3.4$ cm, slightly higher than the elbow height, and the handle distance was $52.9{\pm}2.3$ cm.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.3
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• pp.119-125
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• 2014

Echo cancellation is required for a dual-duplex high speed communication such as digital subscriber line(DSL), in order to allow each individual loop to operate in a full duplex fashion. Echo cancellation was one of the most difficult aspects of DSL design, requiring high linearity and total echo return loss in excess of 70 dB. For a long and rapidly changing echo response, if the echo is cancelled by an adaptive echo canceller, the echo canceller needs more taps and its performance is decreased. But if the response is divided into several responses, which response is estimated by a adaptive digital filter and combined, the computation complexities are decreased and the performance is increased. Therefore, the adaptive multi-stage echo canceller is proposed to decrease the computation complexity and increase the performance of echo return loss, in which the echo canceller is composed of several stage echo canceller estimating each divided echo response. Through computer simulations, this multi-stage echo canceller is verified to have merits for high speed communications such as DSL application.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.556-565
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• 2000

The purpose of this study was to investigate the relationship between perceived stress. self respect & stress response of high school students to provide the basic data for nursing intervention programs in order to manage stress in students. The subject of this study was 279 students (male; 179. female; 100) in high school. Seoul. Korea. during the period from July. 2000. The instruments for this study was a stress management scale developed by Park Young Ae(l996), a self respect scale by Coopersmith (1967) and a physical. emotional response scale to stress by Ro, Jae Hak(1991). The data was analyzed by descriptive statistics, t-test. Pearson correlation coefficient. The results of analysis were as follows: 1) Total perceived stress between males & females didn't show a significant difference but subgroups of stress, 'parent' & 'friend' showed significant differences. Male students were experienced in 'parent' stress than females and female students were more experienced in 'friend' stress than males. 2) A significant negative correlation was revealed between perceived stress & self respect. 3) A significant positive correlation was revealed between self respect & stress response. The result of this study lead us to the suggestion that for high school students. the development of stress management methods for improving self respect should be expanded.

• Journal of Korean Academy of Nursing
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• v.49 no.5
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• pp.562-574
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• 2019

Purpose: The purpose of this study was to identify the response patterns of nursing unit managers regarding workplace bullying. Methods: Q methodology was used to identify the response patterns. Thirty-six Q samples were selected from the Q population of 210 that included literature reviews and in-depth interviews with clinical nurses and nursing managers. Participants were 30 nursing unit managers who had experience managing workplace bullying and they classified the Q samples into a normal distribution frame measured on a nine-point scale. The data were analyzed using the PC-QUANL program. Results: Five types of response patterns were identified: (1) sympathetic-understanding acceleration, (2) harmonious-team approach, (3) preventive-organizational management, (4) passive observation, and (5) leading-active intervention. The preventive-organizational management type was most frequently used by the nursing unit managers. Conclusion: The results of this study indicated that nursing unit managers attempted to prevent and solve workplace bullying in various ways. Therefore, it is necessary to develop and conduct leadership training and intervention programs that appropriately address the response patterns of nursing unit managers, such as those identified in this study.

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.185-191
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• 2018

Post-earthquake risk assessment technique in Korea is developed in 2013 by National Disaster Management Research Institute, at the same time, related manual and standard regulation is distributed to every local government by National Emergency Management Agency. The objectives of this research are to investigate and evaluate the post-earthquake risk assessment of 9.12 Earthquake (M5.8, Gyeongju City, 2016) and 11.15 Earthquake (M5.4, Pohang City, 2017). To suggest and improve the assessment process of post-earthquake risk, first post-earthquake risk assessment method of advanced foreign countries including US, New Zealand and Japan are compared, and post-earthquake evaluation activities in 9.12 Earthquake and 11.15 Earthquake are analyzed. From the results, it is needed to expand the adapted building and structure types and strengthen the earthquake disaster response capacity of local government.

• Journal of the Korea Safety Management & Science
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• v.14 no.3
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• pp.143-150
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• 2012

In Korea more than 38,000 types of hazardous material(HAZMAT) are distributed, accordingly the accidents during transportation are also increasing. The agencies related to HAZMAT such as Environment Ministry, National Emergency Management Agency and National Police Agency have their own regulations. However, the classification criteria of HAZMAT are different to each other, which causes many problems in response to transportation accidents. In this study the classification standard of HAZMAT and the classification code using CAS number are suggested to manage HAZMAT efficiently. Through efficient management and standard classification of HAZMAT, the rapid and systematic response to transportation accidents related to HAZMAT is expected to be possible.