• Journal of Environmental Science International
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• v.22 no.3
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• pp.347-358
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• 2013

The aerosol number concentration have measured with an aerodynamic particle sizer spectrometer(APS) at Gosan in Jeju Island, which is known as background area in Korea, from March 2010 to February 2011. The obtained results of asian dust events and non-asian dust period have been compared. The results show that the entire averaged aerosol number concentration from APS measurement during asian dust events and non-asian dust period are about 341 particles/$cm^3$ and 240 particles/$cm^3$, respectively. During asian dust events, the number concentration in small size ranges(${\leq}0.4{\mu}m$) are similar to non-asian dust period, however, those in large size ranges(${\geq}0.7{\mu}m$) are very higher than non-asian dust period. The contributions of the size resolved number concentration(23 channel in $0.25{\sim}10.0{\mu}m$) to total number concentration in that range are dramatically decreased with increased particle size. The contributions of smaller size ranges(${\leq}0.4{\mu}m$) during asian dust events are very low compared with non-asian dust period, on the other hand, those of larger size ranges(${\geq}0.4{\mu}m$) are higher than non-asian dust period. The number concentration in each size range are strongly correlated with the concentration in adjacent size range. And the total aerosol number concentration are depended on the number concentration in range of smaller than $0.58{\mu}m$ during non-asian dust period and asian dust events. On the other hand, $PM_{10}$ mass concentration has mainly affected with the number concentration in range of smaller than $1.0{\mu}m$ during non-asian dust period, however, during asian dust events, the mass concentration has mainly affected with the number concentration in range of $0.65{\sim}3.0{\mu}m$.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.51.2-51.2
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• 2010

We have investigated 63 intense geomagnetic storms (Dst $\leq$ -100 nT) that occurred from 1998 to 2006. Using these events, we compared Dst forecast models: Burton et al. (1975), Fenrich and Luhmann (1998), O'Brien and McPherron (2000a), Wang et al. (2003), and Temerin and Li (2002, 2006) models. For comparison, we examined a linear correlation coefficient, RMS error, the difference of Dst minimum value (${\Delta}$peak), and the difference of Dst minimum time (${\Delta}$peak_time) between the observed and the predicted during geomagnetic storm period. As a result, we found that Temerin and Li model is mostly much better than other models. The model produces a linear correlation coefficient of 0.94, a RMS (Root Mean Square) error of 14.89 nT, a MAD (Mean Absolute Deviation) of ${\Delta}$peak of 12.54 nT, and a MAD of ${\Delta}$peak_time of 1.44 hour. Also, we classified storm events as five groups according to their interplanetary origin structures: 17 sMC events (IP shock and MC), 18 SH events (sheath field), 10 SH+MC events (Sheath field and MC), 8 CIR events, and 10 nonMC events (non-MC type ICME). We found that Temerin and Li model is also best for all structures. The RMS error and MAD of ${\Delta}$peak of their model depend on their associated interplanetary structures like; 19.1 nT and 16.7 nT for sMC, 12.5 nT and 7.8 nT for SH, 17.6 nT and 15.8 nT for SH+MC, 11.8 nT and 8.6 nT for CIR, and 11.9 nT and 10.5 nT for nonMC. One interesting thing is that MC-associated storms produce larger errors than the other-associated ones. Especially, the values of RMS error and MAD of ${\Delta}$peak of SH structure of Temerin and Li model are very lower than those of other models.

• Journal of Korean Academy of Nursing
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• v.41 no.5
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• pp.704-714
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• 2011

Purpose: The purpose of this study was to determine whether psychological distress is an independent risk factor for recurrent cardiac events in patients with coronary artery disease (CAD). Methods: A prospective cohort of studies that measured psychological distress and the incidence of recurrent cardiac events in the adult population were included. Three computerized databases were assessed (PubMed, CINAHL, and PSYCINFO). Meta-analysis was conducted using a random-effects model to determine summary estimates of risks of major recurrent cardiac events associated with each psychological distress. Of 506 publications identified, 33 met inclusion criteria, and 24 studies were used to estimate effect size of psychological distress on recurrent cardiac events. Results: Mean number in the research sample was 736 and mean time of follow-up was 4.0 years. Depression, anxiety, anger, and hostility as psychological factors were studied. According to estimation of effect size using random model effect, depression (OR=1.39, 95% CI: 1.22-1.57), anxiety (OR=1.22, 95% CI: 0.96-1.56), and anger/hostility (OR=1.29, 95% CI: 1.07-1.57) CAD patients in significantly increased risk for recurrent cardiac events. Conclusion: Finding suggests that psychological distress in forms of depression, anxiety, anger, and hostility impact unfavorably on recurrent cardiac events in CAD patients.

• Journal of Korea Water Resources Association
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• v.40 no.7
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• pp.545-554
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• 2007

This study characterized the storm events recorded in the Annals of Chosun Dynasty and evaluated them using a simple rectangular pulses Poisson process model. Storm events without in detail explanation like Keun-Bi (big rain) were found to have rather short return periods compared to the storm events with lengthy explanation about damages like Keun-Mul (high water), Hong-Soo (flood), and Pok-Woo (torrential rain). Not all storm events recorded were the size of annual maxima, so their return periods were found not to be higher than a certain level. Another noticeable fact is that these storm events recorded seem more sensitive to the storm duration rather than the storm intensity. That is, most storms recorded seem to be focused on long durations rather than high intensities. Those storm events with long durations must have caused serious flood damages, which maybe the critical reason why they were recorded.

• Culinary science and hospitality research
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• v.10 no.1
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• pp.32-45
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• 2004

This study is about choice attribution of customers make in food and beverage events. The researcher provided practical plans to uplift food-related enterprises and activate management through surveys and positive analyses, targeting customers who use food services. First of all, all event plans must include customer demands, social changes, special qualities of the business, and market research. Second, low demand season must be customers will be induced to the events. Third, prediction for market variable and solutions must be thoroughly examined and plans should look into the future to maintain a long period of time. Fourth, sufficient communication between planners and employees should be made before the event starts, so that food and beverage businesses can gain trust and quality of event services.Fifth, immaterial service and visible goods/menus in business of food and beverage events must be closely matched. Sixth, menus introducing a variety of merchandise, quality of nutrition and health of the business should be developed. Also, events from countries(regions) should be hold to create a market of cultural exchange. Seventh, for hereafter event plans, feedbacks are needed concerning customers needs and demands through customer care, after the food and beverage events. Eight, faculty management for convenience, kindness, safety, and life preserver accommodations in parking areas must be made, as automobiles are necessaries for people in Mycar era. The ninth, off-line and on-line care through on-line business construction and production of homepage must be done, due to the fact that even the well-made events are bound to fail if they are not delivered to the customers.

• Journal of Preventive Medicine and Public Health
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• v.34 no.1
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• pp.35-40
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• 2001

Objectives : To elucidate the transient effects on the risk of occupational injuries as acute events and establish so alternative proposal. Methods : The study population comprised a total of 302 workers randomly selected from applications for occupational injury compensation reported to the Inchon local labor office from January 1. 1999 to December 31. A case-crossover design, where each case serves its own control, was applied to this study. Through a telephone interview, workers provided useful data concerning five job related stressful events such as company transfer, work load change, overtime work, exchange duty, and work-part transfer. They were asked whether there were stressful events within a week of the occurrence of injury and the degree of stress. Exposure status from one year prior was used as control information. In the end, the data provided by 158 of selected persons was used for the analysis based on the quality of the data provided by the participants. A conditional logistic regression was used to discover the transient effects on the risk of occupational injuries as acute events. Results : The effects a company transfer and work load change on occupational injury was statistically significant on the risk of occupational Injuries as an acute event(RR=5.5, 95% CI=2.501-12.428; RR=3.1, 95% CI=1.963-5.017, respectively). Other stressful events were found to elevate the risk factor for the occurrence of occupational jujury, but were not significant. Conclusions : Our results suggested that transient stressful events elevated the risk factor for the occurrence of occupational injury.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.52-57
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• 1999

Korea Earthquake Monitoring System(KEMS) in the Korea Institute of Geology Mining and Materials(KIGAM) as detected more than 1000 events since the end of 1998. But not all events are interpreted as earthquakes because many events are concentrated on daytime. It strongly implies that in addition to earthquake these events include artificial effects such as industrial blasting. Before the determination of eathquake charactertistics in the korean peninsula it is necessary to discriminate the detected events as earthquakes or artificial events. For the discriminant study KIGAM and SMU(Southern Methodist University) installed a triangular four-element 1-km aperture seismo-acoustic array at Chul-Won area northeast of Seoul Korea. Each array element includes a GS-13 seismometer in the bottom of borehole and a Validyne DP250-14 microbarometer sensor mounted inside of the borehole 1,2 meter deep connected to a 11 arm radial array of 10m porous soaker hoses. This array introduce the use of 2.4-GHz radios for inter-array self-contained solar-charged power system and GPS time-keeping system. A 24-bit digital data acquisition system performs 40 SPS in the infrasound and seismometer data. Velocity and direction of wind and temperature are also measured at hub site and included to the data stresam. This seismo-acoustic array will be used to identify and locate associated with industrial blasting and these identified and located events will be applied to form a ground truth database useful to assist the other development of discriminant studies.

• Journal of the Korea Safety Management & Science
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• v.22 no.2
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• pp.57-71
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• 2020

The purpose of this study is to explore the effects of fire officers' experience of traumatic events and subsequent forest healing on their occupational burnout. The results are as follows: First, the experience of traumatic events, social and psychological healing, and relieving stress by strolling had a significant effect on burnout. The more fire officers are exposed to traumatic events, the more they lose self-control in social and psychological aspects, and the lower the level of stress relieved through strolling, the higher the level of burnout. Thi sresult suggests that the more fire office rsare called out for fire fighting, the more they see their colleagues with severein juries, and the higher the level of mental and physical an xiety, the more they areex hausted. Moreover, for es thealing help store duce the irmental and physi calfatig uecaused by traumatic events, thu spreven ting them from suffering from burn out. Second, the experience of traumatic events, social and psychological healing, and relieving stress by strolling had a significant impact on occupational stress. The more fire officers are exposed to traumatic events, the more they lose self-control in social and psychological aspects, and the lower the level of stress relieved through strolling, the higher the level of occupational stress. This result indicates that to relieve job stress caused by fire fighting, increased forest healing activities, including various programs such as psychotherapy, developing interpersonal relationships and self-control, and creating a positive mind-set, can reducejobstress and help fire officers recover from it. Lastly, job stress had a mediation effect on the effects of the experience of traumatic events and forest healing on burnout. This implies that burnout can be prevented when fire officers gain high emotional stability through social and psychological healing and stress-relief strolling over a traumatic experience, and stronger support from the organization and family can keep them from being emotionally drained, thus contributing to the prevention of burnout.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.6
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• pp.1255-1261
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• 2020

Cache side-channel attack is a class of attacks to retrieve sensitive information from a system by exploiting shared cache resources in CPUs. As the attacks are delivered to wide range of environments from mobile systems to cloud systems recently, many detection strategies have been proposed. Since the conventional cache side-channel attacks are likely to incur tremendous number of cache events, most of the previous detection mechanisms were designed to carefully monitor mostly cache events. However, recently proposed attacks tend to incur less cache events during the attack. PRIME+ABORT attack, for example, leverages the Intel TSX instead of accessing cache to measure access time. Because of the characteristic, attack detection mechanisms based on cache events may hardly detect the attack. In this paper, we conduct an in-depth analysis of the PRIME+ABORT attack to identify the other useful hardware events for detection rather than cache events. Based on our finding, we present a novel mechanism called PRIME+ABORT Detector to detect the PRIME+ABORT attack and demonstrate that the detection mechanism can achieve 99.5% success rates with 0.3% performance overhead.

• Korean Journal of Culture and Social Issue
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• v.11 no.1
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• pp.85-108
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• 2005

This study was to conceptualize Palzha and investigate Palzha inference as mode of self-view. In general, people would like to attribute their unhappy and unfortunate life events or histories to Palzha which is given by the supernatural being. According to analysis of interviews and open-ended responses concerning on Plazha, Palzha indicated 'luck', 'uncontrollable situation', or 'fate' given by the supernatural being. In study 2, we conducted an analysis of the relationship between locus of control belief and Palzha attribution. More having external control belief, more tending to attributing the rugged life events or histories, and unexpected fortunate events to Palzha. Consequently, Palzha as mode of self-view on everyday events or life-events indicated it is likely to be another dimension of attribution on negative as well as positive life events in Korean culture.