• Journal of IKEEE
• /
• v.23 no.3
• /
• pp.805-810
• /
• 2019

We present a time-frequency analysis algorithm based on the multitaper method and the state-space frameworks. In general, time-frequency representations have a trade-off between the time duration and the spectral bandwidth by the uncertainty principle. To optimize the trade-off problems, the short-time Fourier transform and wavelet based algorithms have been developed. Alternatively, the authors proposed the state-space frameworks based on the multitaper method in the previous work. In this paper, we develop a real-time algorithm to estimate variances and spectrum using the state-space framework. We test our algorithm in spectral analysis of simulated data.

• Journal of Practical Engineering Education
• /
• v.11 no.1
• /
• pp.105-115
• /
• 2019

This study focused on the importance of job position as a role model for female career adaptation. To do this, we used the KWMP data to conduct a Multinomial logit analysis to examine the influence factors of the tenure women managers. As a result, first, section chief position showed a low level of life satisfaction and showed difficulty of beginner's manager. Second, it is predicted that the position of the Deputy Head of Department will establish the identity of work as an intermediate manager. Third, head of department Director showed a high age, target status, possibility of achieving the target, and duration of the next job. Fourth, executive level has the least average experience of discrimination on monthly average wage. It was suggested that it is important to develop individual career by recognizing that the organizational atmosphere and personnel management are lower than those of the other positions. It was found that age, organizational atmosphere and personnel management, goal status, possibility of achieving goals, next job tenure period, monthly average wage, welfare, and life satisfaction factors were the most influential factors in women career adjustment. Finally, implications and limitations were discussed based on the results of this study.

• Korean Journal of Metals and Materials
• /
• v.48 no.3
• /
• pp.256-261
• /
• 2010

In this work, high-k dielectric stacks of $HfO_2$ and $HfO_2$/$Al_2O_3$/$HfO_2$ (HAH) were deposited on $SiO_2/Si$ substrates by atomic layer deposition as charge trapping layers in charge trapping devices. The structural stability and the charge trapping characteristics of such stacks were investigated using Metal-Alumina-Hafnia-Oxide-Silicon (MAHOS) structure. The surface roughness of $HfO_2$ was stable up to 11 nm with the insertion of 0.2 nm thick $Al_2O_3$. The effect of the thickness of the HAH stack and the thickness of intermediate $Al_2O_3$ on charge trapping characteristics were investigated for MAHOS structure under various gate bias pulse with duration of 100 ms. The threshold voltage shift after programming and erase showed that the memory window was increased with increasing bias on gate. However, the programming window was independent of the thickness of HAH charge trapping layers. When the thickness of $Al_2O_3$insertion increased from 0.2 nm to 1 nm, the erase window was decreased without change in the programming window.

• Safety and Health at Work
• /
• v.12 no.1
• /
• pp.74-95
• /
• 2021

Background: A job-exposure matrix (JEM) is an important surrogate indicator to evaluate past exposure levels. Although a Korean asbestos JEM has been constructed previously, this JEM includes only a few industrial and occupational groups. This study aimed to reconstruct the JEM by integrating the latest organized data to improve its utility. Methods: We used recent Korean standard industry and occupation codes and extracted 36 articles from a systematic literature review to initiate the reconstruction of the previous Korean asbestos JEM. The resulting data consisted of 141 combinations of industrial and occupational groups. Data from the Netherlands's JEM were also reviewed and categorized into 70 industrial and 117 occupational groups by matching with the Korean data. We also utilized Germany's data, which consisted of 10 industrial and 14 occupational groups. Results: The reconstructed Korean asbestos JEM had 141 combinations of industries and occupations. The time periods are from the 1980s to the 2000s in 10-year intervals. Most of the data were distributed between the 1990s and the 2000s. Occupations with high exposure to asbestos included knitting and weaving machine operators, automobile mechanics or assemblers, ship mechanics or assemblers, mineral ore and stone products processing mechanics, and metal casting machine operators or mold makers. Conclusions: The reconstructed Korean asbestos JEM has expanded the type and duration of the occupational groups of the previous JEM and can serve as an important reference tool for evaluating asbestos exposure and designing compensation and prevention policies in Korea.

• Journal of Environmental Science International
• /
• v.30 no.8
• /
• pp.621-628
• /
• 2021

The characteristics of time changes in air temperature, DI (discomfort index) and WBGT (wet-bulb globe temperature) were investigated for inland city (daegu) and coastal city (pohang) of Gyeongbuk Province during the 2018 consecutive heat wave season. The time when the temperature dropped below 33℃ was around 19h in both regions. As such, the two regions were similar with respect to the time up to which the heatwave warning levels continued. However, the discomfort index (DI) was higher than 27 in Pohang. Most people feel unpleasant when an discomfort index of 27 or higher appears. The results indicated that Korea's night-time thermal environment during the summers is particularly poor in the southern coastal areas. WBGT began at 09:00 and lasted until 21:00, with a score of 31 or higher; this score, in principle, corresponded with the duration of outdoor activity in both regions. Therefore, it was found that outdoor work was at a level where all day long had to be stopped in both areas during the heat wave. Although time changes in temperature and WBGT were similar in both regions, Discomfort Index (DI) differed significantly. The difference refers to the fact that Pohang is strongly affected by the high heat capacity effect and the supply of water vapor from the sea.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.25 no.3
• /
• pp.97-111
• /
• 2022

This study was conducted as restoration work to improve the discharge in forested wetlands where there is a concern of damage and observed changes in the discharge and groundwater level. The monthly changes showed that during the wet season, the amount of discharge decreased after restoration and GWL increased. It showed that during the dry season, the GWL and discharge increased. The increased discharge after restoration seems to be the difference in the number of days with no rainfall duration. The change in discharge for each unit of rainfall showed a tendency to increase the baseflow and decrease the direct discharge after restoration. The recharge ratio of GWL showed a decreasing tendency as rainfall was higher. After restoration, it showed a higher tendency under rainfall with less than 20mm. It has been confirmed that the restoration implemented by the study caused such an effect as the increased baseflow and increased GWL. It would be an effective restoration method to maintain water resources in forested wetlands. In the initial rainfall, it demonstrated a certain level of effect, but it is necessary to develop a restoration technology that can decrease the amount of water discharged after the end of rainfall or during the period of no rainfall to protect and maintain the forested wetlands. Streamflow should be identified by each type of terrain of wetlands and a proper restoration countermeasure should be devised for the site where the discharge frequently occurs.

• Journal of East-West Nursing Research
• /
• v.28 no.2
• /
• pp.170-178
• /
• 2022

Purpose: This study aimed to identify the factors influencing post-traumatic stress disorder in intensive care unit nurses in dedicated hospitals for coronavirus disease of 2019 (COVID-19) during the peak of the outbreak. Methods: This study used a cross-sectional correlational design. A total of 100 participants completed questionnaires comprising the Impact of Event Scale-Revised (IES-R), coping strategy indicator, social support, and post-traumatic growth. Post-traumatic stress disorder was classified as normal, mild risk, and high risk. Data were analyzed using 𝛘² test, Fisher's exact test, Kruskal-Wallis test with multiple comparison analysis, Pearson correlation coefficient, and multinominal logistic regression analysis. Results: Fifty seven nurses (57.0%) had a high risk of post-traumatic stress. Higher levels of post traumatic stress were associated with higher levels of social support seeking, and higher levels of avoidance, and lower levels of social support from supervisors. Higher post traumatic growth was correlated with higher social support for seeking coping, and problem solving coping strategies, and social support from supervisors and colleagues. Post-traumatic stress risk was associated with social support seeking and supervisors' social support. In addition, a higher risk of post-traumatic stress was related to COVID-19 work duration and supervisors' social support. Conclusion: Supportive programs, including increasing social support and building coping skills, may be suggested to safeguard the mental health of critical care nurses during the pandemic.

• Archives of Plastic Surgery
• /
• v.49 no.3
• /
• pp.289-295
• /
• 2022

Background Massive weight loss (MWL) is a very common presentation that you may face as a plastic surgeon. Each patient has his own individual criteria, so, you should work according to a well-organized plan, especially when such cases have concerns about their gluteal area contour that were neglected before by many surgeons. A decision-making strategy was used to give a personalized treatment for targeting gluteal region reshaping of MWL patients. Methods This study considered all patients with MWL subjected to buttock reshaping. There was no randomization in treatment; there was a case-by-case assessment. We analyzed the features of the buttocks, the type of surgery performed, the outcomes, and the complications. Results Fifty two patients were included (41 females and 11 males), ages ranged between 21 and 66 years. Demographic data, preoperative body mass index (BMI), duration of surgery, type of surgery, and postoperative complications were collected. Statistically significant improvements were observed in gluteal ptosis and patient satisfaction grades. Conclusion Aesthetic improvement of the buttocks involves either augmentation or contouring that may be obtained by liposculpture, surgical lifting, or combination. Patients with MWL have high expectations and are often treated with multiple procedures. Thus, an easy strategic approach personalized on each patient to treat multiple adjacent areas in one operation is necessary. Adipose tissue distribution, gluteal skin status, and BMI were the main factors that can forcefully affect our plan to guarantee reduction of unpleasant results and complications and improve patient satisfaction.

• International Journal of Computer Science & Network Security
• /
• v.22 no.12
• /
• pp.153-159
• /
• 2022

The article discusses the use of smart technologies in the training of future specialists. Today, learning using smart technologies is becoming a new educational standard, where information is presented in a logical sequence, computer training systems have powerful functions for the educational process. The functions of smart technologies are highlighted. It is noted that smart technologies are successfully used in the field of education and professional training. The concept of "smart education" is characterized. Smart education is an educational paradigm that underlies a new type of education system. The implementation of the smart education paradigm is aimed at the process of obtaining competencies and competencies for flexible and adapted interaction with the social, economic and technological environment. Smart education should ensure that the benefits of the global information society can be used to meet educational needs and interests. A special place is occupied by computer-based educational multimedia systems that allow you to deepen your knowledge, reduce the duration of training, and increase the number of students per teacher. The main principles of smart education are highlighted. Improving the efficiency of training in a modern higher education institution is impossible without the introduction of smart technologies in the organization of the educational process.

• Journal of the Korean Geosynthetics Society
• /
• v.22 no.3
• /
• pp.27-35
• /
• 2023

Ensuring the stability of visible structures during excavation works are extremely crucial. While the stability of the ground is analyzed through numerical calculations the during design phase, the conditions during construction often differ. Therefore, it is imperative to analyze the stability of the wall through measurements. The cost of measurements on the construction site is set at a very low unit price, which increases the risk of accidents involving retaining walls. In this study, we argue for the importance of automated or wireless system measurements of retaining walls, by estimating construction duration and accident costs through the analysis of hypothetical accident cases, and comparing these with measurement costs. In case of a major destruction during excavation work, the accident handling cost could be less than 5% of the total measurement budget. Therefore, increasing the measurement budget to prevent accidents in advance can be economically beneficial.