• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.5
• /
• pp.332-338
• /
• 2016

This study examined the posttraumatic growth of North Korean defectors, the relation between their characteristics and posttraumatic growth and the factors influencing their posttraumatic growth, and explored methods of improving their mental health status. 145 North Korean defectors, who were trained in B city and G city, participated in the survey from February 1 to March 10, 2016. The posttraumatic growth, resilience, self-esteem, deliberate rumination, and impact of the (traumatic) event were measured using the PTGI (Posttraumatic Growth Inventory), RS (Rumination Scale, Resilience Scale), SES (Self-esteem Scale) and ISR (Impact of Event). The data were analyzed using the t-test, ANOVA, Pearson correlation coefficient and stepwise multiple regression. The mean scores were 29.64 for posttraumatic growth. There were significant positive correlations between posttraumatic growth and resilience and between posttraumatic growth and rumination. The influence of the independent variables on the total posttraumatic growth was examined using regression analysis. Models including the variables (resilience, positive self-esteem, and rumination) explained 54.2% of the variance for the posttraumatic growth. These findings demonstrate that it is essential for nurses to continuously intervene and help North Korean defectors so as to promote their posttraumatic growth and resilience. Furthermore, it is also necessary for nurses to find ways to develop ideal interventions in order to activate deliberate rumination.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.19 no.2
• /
• pp.119-128
• /
• 2013

Since the early 2000s, demand for coastal dredging projects have been significantly increased, and the dredged sediments have showed the continuing marked increases through the multiple projects with other coastal development and constructions. As significant or potential degradation of marine environment has been mounting, we checked the current situation of marine environmental impact assessment through marine water and sediment qualities in relation with dredging projects of the sea area utilization consultation statements submitted in 2011. While analysis percentages of the general items were usually higher, harmful components such as metals revealed wide variation of analysis percentages. In the event of analysis of metals, the pre-treatment process (full digestion) and analysis method were not properly implemented in accordance with the guidelines for preparation of consultation statements. Although not specified in the guidelines, verification procedures (tests of recovery efficiency and detection limit) to secure the reliability were almost ignored. As a result, most of developers did conduct poor marine environmental impact assessment on coastal dredging and related projects. We suggested that the responsible government authority should establish new detailed guidelines on the sea area utilization consultation for more strict evaluation and diagnosis of marine environment and distinctly request the developer to obey the guidelines by complementing the system of the sea area utilization consultation.

• Journal of the Korean Institute of Gas
• /
• v.21 no.1
• /
• pp.43-51
• /
• 2017

Recently, ammonia leak occurred frequently in the domestic refrigeration manufacturing facilities. Ammonia caused great damage to the environment and human health in the event of an accident as combustible gases and toxic gases. After considering the types of ammonia accidents of domestic refrigeration manufacturing facilities and selected accident scenarios and to analyze the risk analysis through Impact range estimates and frequency analysis and there was a need to establish measures to minimize accident damage. In this study, depending on the method of analysis quantitative risk assessment we analyzed the risk of the receiver tank of ammonia system. Scenario analysis conditions were set according to the 'Technical guidelines for the selection of accident scenario' under the chemicals control act and 'Guidelines for chemical process quantitative risk analysis' of center for chemical process safety. The risk estimates were utilized for consequence analysis and frequency analysis by SAFETI program of DNV, event tree analysis methodology and part count methodology. The individual risk of ammonia system was derived as 7.71E-04 / yr, social risk were derived as 1.17E-03 / yr. The derived risk was confirmed to apply as low as reasonably practicable of the national fire protection association and through risk calculation, it can be used as a way to minimize accidents ammonia leakage accident damage.

• Journal of Korea Water Resources Association
• /
• v.51 no.8
• /
• pp.703-711
• /
• 2018

Water distribution system (WDS) pipe bursts are caused from excessive pressure, pipe aging, and ground shift from temperature change and earthquake. Prompt detection of and response to the failure event help prevent large-scale service interruption and catastrophic sinkhole generation. To that end, this study proposes a improved Western Electric Company (WECO) method to improve the detection effectiveness and efficiency of the original WECO method. The original WECO method is an univariate Statistical Process Control (SPC) technique used for identifying any non-random patterns in system output data. The improved WECO method multiples a threshold modifier (w) to each threshold of WECO sub-rules in order to control the sensitivity of anomaly detection in a water distribution network of interest. The Austin network was used to demonstrated the proposed method in which normal random and abnormal pipe flow data were generated. The best w value was identified from a sensitivity analysis, and the impact of measurement frequency (dt = 5, 10, 15 min etc.) was also investigated. The proposed method was compared to the original WECO method with respect to detection probability, false alarm rate, and averaged detection time. Finally, this study provides a set of guidelines on the use of the WECO method for real-life WDS pipe burst detection.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.5
• /
• pp.1-9
• /
• 2016

Railroad bridges account for 25% of the entire high-speed rail network. Railway bridges are subject to gradual structural degradation or fatigue accumulation due to consistent and repeating excitation by fast moving trains. Wireless sensing technology has opened up a new avenue for bridge health monitoring owing to its low-cost, high fidelity, and multiple sensing capability. On the other hand, measuring the transient response during train passage is quite challenging that the current wireless sensor system cannot be applied due to the intrinsic time delay of the sensor network. Therefore, this paper presents a framework for monitoring such transient responses with wireless sensing systems using 1) real-time excessive vibration monitoring through ultra-low-power MEMS accelerometers, and 2) post-event time synchronization scheme. The ultra-low power accelerometer continuously monitors the vibration and trigger network when excessive vibrations are detected. The entire network of wireless smart sensors starts sensing through triggering and the post-event time synchronization is conducted to compensate for the time error on the measured responses. The results of this study highlight the potential of detecting the impact load and triggering the entire network, as well as the effectiveness of the post-event time synchronized scheme for compensating for the time error. A numerical and experimental study was carried out to validate the proposed sensing hardware and time synchronization method.

• Journal of Korea Water Resources Association
• /
• v.54 no.11
• /
• pp.925-932
• /
• 2021

A drought-flood abrupt alternation event is an overlapping extreme event that is harder to cope with than a single event of drought and flood. It is also expected to have a significant adverse impact on ecosystems as well as industries and agriculture. However, there has not yet been a comprehensive study that characterizes the drought-flood abrupt alternation events in Korea. Therefore, this study employed a standard weighted average precipitation (SWAP) index, which is efficient to analyze not only individual events of drought and flood but also the drought-flood abrupt alternation events considering various time scales. The SWAP standardized the weighted average precipitation (WAP) by adding temporal weights to the precipitation. The SWAP indices were calculated for middle-sized watersheds of the Han River basin using the area average precipitation during 1966 and 2018. The severity K was calculated to represent the relative regional severity considering normal rainfalls, and used to characterize the drought-flood abrupt alternation in the study areas. The results indicated that 20 of the 30 middle-sized watersheds in the Han River basin were confirmed to increase the severity of drought-flood abrupt alternation over time. Considering the frequency and severity of drought-flood abrupt alternation events in each watershed, vulnerable areas and dangerous areas due to drought-flood abrupt alternation were identified, for example, the Upstream Namhan River (#1001).

• Economic Analysis
• /
• v.27 no.1
• /
• pp.1-36
• /
• 2021

Given the US dollar's status as a global safe haven, global factors, such as US monetary policy, may have considerable impacts on financial markets in other countries. Regarding such hypothesis, this paper looked at the impacts of US monetary policy on domestic bond and FX swap markets through an event study. According to our analysis, US monetary policy had significant positive impacts on domestic interest rates. In particular, it turned out to have bigger impacts on long-term products with high term premiums. By period, the correlation between US monetary policy and domestic interest rates was not significant before the financial crisis, but was clearly positive after the crisis. The US conventional monetary policy was seen to have big impacts on short-term and medium-term KTB yields, while its unconventional monetary policy had major impacts on long-term KTB yields. Moreover, FX swap rates reacted very sensitively to US monetary policy shocks before the financial crisis, while they did not show any significant reactions after the crisis. This suggests that, in line with the covered interest rate parity, the impact of US monetary policy shocks was transmitted to domestic financial markets mainly through swap rate adjustments before the global financial crisis, but through the changes in domestic interest rates during the post-crisis period.

• Korea Trade Review
• /
• v.42 no.5
• /
• pp.113-136
• /
• 2017

New product preannouncement through global supply chain management and international strategic alliances is a critical issue for firm's survive and gaining the competitive advantage in the global smart-phone market. To identify the impact of exploration alliance and exploitation alliance on the short-term's Firm Performance, respectively, This study implemented the event study and the cross sectional regression analysis, focusing on the case of Galaxy Note series. Research results identified that new technologies by exploration alliance and the existing technologies through exploitation alliance have a positive effect on the short-term's performance of vendors related. Furthermore, information for the new products showed higher the excess earning rate than information related to the existing technologies. This implies the firms that provides new technologies have a stronger innovative ability than the companies serving the existing technologies, recognizing as a positive signal in the market. Finally, this study implicates that new technologies by exploration alliance enhances innovative abilities from new product preannouncement, and is a critical variable that can determines whether to survive in the market.

• Safety and Health at Work
• /
• v.14 no.3
• /
• pp.317-324
• /
• 2023

Background: COVID-19 pandemic represented a unique stressful event that affected the physical health and psychological well-being (PWB) of individuals and communities. Monitoring PWB is essential not only to clarify the burden on mental health effects but also to define targeted psychological-supporting measures. This cross-sectional study evaluated the PWB of Italian firefighters during the pandemic. Methods: Firefighters recruited during the pandemic period filled out a self-administered questionnaire, the Psychological General Well-Being Index, during the health surveillance medical examination. This tool is usually used to assess the global PWB and explores six subdomains: anxiety, depressed mood, positive well-being, self-control, general health, and vitality. The influencing roles of age, gender, working activities, COVID-19, and pandemic restrictive measures were also explored. Results: A total of 742 firefighters completed the survey. The aggregate median PWB global score was in the 'no distress"" range (94.3 ± 10.3), which was higher than that observed in studies conducted using the same tool in the Italian general population during the same pandemic period. Similar findings were observed in the specific subdomains, thus suggesting that the investigated population was in good PWB condition. Interestingly, significantly better outcomes were detected in the younger firefighters. Conclusion: Our data showed a satisfactory PWB situation in firefighters that could be related to different professional factors such as work organization and mental and physical training. In particular, our results would suggest the hypothesis that in firefighters, maintaining a minimum/moderate level of physical activity (consisting of even just going to work) might have a profoundly positive impact on psychological health and well-being.

• Monthly Notices of the Royal Astronomical Society
• /
• v.496 no.4
• /
• pp.4787-4821
• /
• 2020

The merging rate of cosmic structures is computed, relying on the ansatz that they can be predicted in the initial linear density field from the coalescence of critical points with increasing smoothing scale, used here as a proxy for cosmic time. Beyond the mergers of peaks with saddle points (a proxy for halo mergers), we consider the coalescence and nucleation of all sets of critical points, including wall-saddle to filament-saddle and wall-saddle to minima (a proxy for filament and void mergers, respectively), as they impact the geometry of galactic infall, and in particular filament disconnection. Analytical predictions of the one-point statistics are validated against multiscale measurements in 2D and 3D realizations of Gaussian random fields (the corresponding code being available upon request) and compared qualitatively to cosmological N-body simulations at early times (z ≥ 10) and large scales (≥5 Mpc h^-1). The rate of filament coalescence is compared to the merger rate of haloes and the two-point clustering of these events is computed, along with their cross-correlations with critical points. These correlations are qualitatively consistent with the preservation of the connectivity of dark matter haloes, and the impact of the large-scale structures on assembly bias. The destruction rate of haloes and voids as a function of mass and redshift is quantified down to z = 0 for a Lambda cold dark matter cosmology. The one-point statistics in higher dimensions are also presented, together with consistency relations between critical point and critical event counts.