• Korean Journal of Psychosomatic Medicine
• /
• v.30 no.1
• /
• pp.7-15
• /
• 2022

Objectives : The purpose of this study is to identify the effect of office workers' stress level and stress vulnerability on heart rate variability (HRV), confirm the significance of objective stress indicators obtained through subjective stress and heart rate variability devices, and examine their effectiveness as an integrated stress measurement tool in community mental health projects. Methods : From June to July in 2020, 929 workers participated in the stress management and mental health promotion project carried out by K hospital, and their recorded database was used for study analysis with their agreements. Multiple linear regression analysis was performed to find out the effects of general stress level, and stress vulnerability on heart rate variability. Results : All general characteristics were found to have a significant effect on SDNN (ln), RMSSD (ln), LF (ln), and HF (ln), but work experience did not significantly affect RMSSD (ln). Stress level and stress vulnerability did not significantly affect heart rate variability, but stress perception, a sub-factor of stress level, was found to have a significant effect on RMSSD (ln) (β=0.118, p=0.023). Conclusions : In this study, stress perception, a sub-factor of stress level, was found to be a factor affecting RMSSD (ln). This indicates an association with the activity of parasympathetic nerves in stressful situations, and more follow-up studies are needed to use it as a direct indicator of chronic stress and integrated stress in the community mental health field.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.9
• /
• pp.1-12
• /
• 2022

Traditional methods of measuring corneal ulcers were difficult to present objective basis for diagnosis because of the subjective judgment of the medical staff through photographs taken with special equipment. In this paper, we propose a method to detect the ulcer area on a pixel basis in corneal ulcer images using a semantic segmentation model. In order to solve this problem, we performed the experiment to detect the ulcer area based on the DeepLab model which has the highest performance in semantic segmentation model. For the experiment, the training and test data were selected and the backbone network of DeepLab model which set as Xception and ResNet, respectively were evaluated and compared the performances. We used Dice similarity coefficient and IoU value as an indicator to evaluate the performances. Experimental results show that when 'crop & resized' images are added to the dataset, it segment the ulcer area with an average accuracy about 93% of Dice similarity coefficient on the DeepLab model with ResNet101 as the backbone network. This study shows that the semantic segmentation model used for object detection also has an ability to make significant results when classifying objects with irregular shapes such as corneal ulcers. Ultimately, we will perform the extension of datasets and experiment with adaptive learning methods through future studies so that they can be implemented in real medical diagnosis environment.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.6
• /
• pp.921-926
• /
• 2022

Sugar solutions (5%, 10%, 15% and 20%) were tested by seven sensors of Astree E-Tongue for selecting a sensor for sweetness. NMS sensor was chosen as a sensor for sweetness among two sensors (PKS and NMS sensors selected in first stage) by considering precision, linearity and accuracy. Sugar, fructose, glucose and xylitol (5%, 10% and 15%) were tested by E-tongue. The principal component analysis (PCA) result by E-Tongue with seven sensors at 5% concentration level of four sweetners was not satisfactory (Discrimination index was -0.1). On the other hand, the relative NMS sensor response values were derived as 1.08 (fructose), 0.99 (glucose) and 1.00 (xylitol) comparing to sugar. Only the E-Tongue relative glucose response 0.99 was different from 0.5~0.75 of the relative sweetness range reported as the human sensory test results. Considering the excellent precision (%RSD, 1.53~3.64%) of E-Tongue using NMS single sensor for three types of sweeteners compared to sugar in the concentration range of 5% to 15%, replacing sensory test of sweetened beverages by E-Tongue might be possible for new product development and quality control.

• Journal of the Korea Society for Simulation
• /
• v.18 no.4
• /
• pp.39-47
• /
• 2009

Recently, the threat of DDoS attacks is increasing and many companies are planned to deploy the DDoS defense solutions in their networks. The DDoS attack usually transmits heavy traffic data to networks or servers and they cannot handle the normal service requests because of running out of resources. Since it is very hard to prevent the DDoS attack beforehand, the strategic plan is very important. In this work, we have conducted modeling and simulation of the DDoS attack by changing the number of servers and estimated the duration that services are available. In this work, the modeling and simulation is conducted using OPNET Modeler. The simulation result can be used as a parameter of trade-off analysis of DDoS defense cost and the service's value. In addition, we have presented a way of estimating the cost effectiveness in deployment of the DDoS defense system.

• Smart Media Journal
• /
• v.11 no.11
• /
• pp.49-62
• /
• 2022

Recently, with the development of Smart City Solutions such as Big data, AI, IoT, Autonomous driving, and Digital twins around the world, the proliferation of various smart devices and social media, and the record of the deeds that people have left everywhere, the construction of Smart Cities using the "Big Data" environment in which so much information and data is produced that it is impossible to gauge the scale is actively underway. The Purpose of this study is to construct an objective and systematic analysis Model based on Big Data to improve the transportation convenience of citizens and formulate efficient policies in Urban Information and Public Transportation accessibility in sustainable Smart Cities following the 4th Industrial Revolution. It is also to derive the methodology of developing a Big Data-Based public transport accessibility and policy management Platform using a sustainable Urban Public DB and a Private DB. To this end, Detailed Living Areas made a division and the accessibility of basic living amenities of Gwangju Metropolitan City, and the Public Transportation system based on Big Data were analyzed. As a result, it was Proposed to construct a Big Data-based Urban Information and Public Transportation accessibility Platform, such as 1) Using Big Data for public transportation network evaluation, 2) Supporting Transportation means/service decision-making based on Big Data, 3) Providing urban traffic network monitoring services, and 4) Analyzing parking demand sources and providing improvement measures.

• Science of Emotion and Sensibility
• /
• v.25 no.4
• /
• pp.95-106
• /
• 2022

This study evaluated the effects of latex mattresses on sleep quality and comfort. The participants were 11 healthy adults (five males, six females, mean age 37.7 years, mean height 167.8 cm, and mean weight 67.0 kg) without severe insomnia or other disease that could affect sleep, examined by a clinician. In their personal living space, participants slept on a spring mattress for 7 days, with their sleep registered using a wearable device (Fitbit), a sleep log, the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), and a satisfaction survey. The mattresses were then replaced with latex mattresses, which were used for 14 days. As a result, sleep time increased by 62.9 min on weekdays and 53.2 min on weekends after using the latex mattress, and a significant decrease, of 3.8, as seen on the ISI. As measured by the PSQI, the poor sleepers decreased from 10 to 7, but this was not statistically significant, and in the satisfaction survey, the comfort of the low back, neck, and shoulders was significantly increased. This suggests that changes to latex mattresses may positively affect objective and subjective sleep quality.

• The Journal of Bigdata
• /
• v.7 no.2
• /
• pp.153-172
• /
• 2022

Online shopping has transformed and rapidly grown the entire market at the forefront of wholesale and retail services as an effective solution to issues such as digital transformation and social distancing policy (COVID-19 pandemic). Small business owners, who form the majority at the center of the online shopping industry, are constantly collecting policy changes and market trend information to overcome these problems and use them for marketing and other sales activities in order to overcome these problems and continue to grow. Objective and refined information that is more closely related to the business is also needed. Therefore, in this paper, through the collection and analysis of big data information, which is the core technology of digital transformation, key variables are set in product classification, sales trends, consumer preferences, and review information of online shopping malls, and a method of using them for competitor comparison analysis and business sustainability evaluation has been prepared and we would like to propose it as a service. If small and medium-sized businesses can benchmark competitors or excellent businesses based on big data and identify market trends and consumer tendencies, they will clearly recognize their level and position in business and voluntarily strive to secure higher competitiveness. In addition, if the sustainable growth of the online shopping mall operator can be confirmed as an indicator, more efficient policy establishment and risk management can be expected because it has an improved measurement method.

• Journal of Service Research and Studies
• /
• v.11 no.4
• /
• pp.43-55
• /
• 2021

This study analyzed the efficiency of medical services in OECD member countries by dividing it into operational efficiency and quality efficiency. For this purpose, data from 2017-2019 OECD Health Statistics were used. As the analysis method, super efficiency was measured by applying an output-oriented Variable Returns to Scale (VRS) model. As a result of the analysis, Switzerland, Korea, and Italy were included in the high group of operational efficiency, Canada, Greece, Denmark, etc. in the medium group, and Belgium, Germany, and Spain in the low group. Based on quality efficiency, Norway, Switzerland, and Spain are in the high group, and Greece, Denmark, Mexico, etc. are in the medium group, and the Netherlands, Germany, Belgium, etc. were included in the low group. As a result of comparative analysis of efficiency by OECD member countries as of 2018, it was found that Korea's operational efficiency was the most efficient and quality efficiency was inefficient. Korea (0.998) should improve life expectancy by 0.2 (0.2%) and subjective health perception by 44.2 (138.1%) by benchmarking Greece (0.422), Switzerland (0.207), and Spain (0.371) to improve quality efficiency. Unlike most previous studies that focused on operational efficiency, this study measured quality efficiency together and analyzed the efficiency of the medical service industry in each OECD member country. Through this, this study has implications in that it confirmed the international competitiveness of the domestic medical service industry and suggested ways to improve efficiency.

• Journal of Korean Society of Archives and Records Management
• /
• v.23 no.2
• /
• pp.69-94
• /
• 2023

This study analyzes the system and operational status of regional documentation programs conducted by local governments and aims to propose considerations for the sustainability of regional documentation programs. With the government's balanced national development policy, the city or culture departments of local governments promoted regional documentation programs as part of their urban and cultural policies. Each local government enacted landscape ordinances and the ordinances concerning the establishment and operation of urban historical and cultural archives and promoted urban regeneration projects. Based on this, local governments performed urban landscape documentation, urban historical and cultural archives, and urban regeneration project documentation. Consequently, this study compared and analyzed ordinance enactment, budget, acquisition, management, and utilization of records for a total of 55 cases. The study has found that legislation is an essential factor in the sustainability of local governments' regional documentation programs. In addition, it suggested that regional documentation programs should evaluate the performance of programs, ensure residents' participation, and create digital archives to secure the budget continuously. This study is significant because it evaluates the overall regional documentation cases of local government city or culture departments as part of the city or culture policy rather than a specific region or case and presents more objective and general considerations for sustainability

• Journal of The Korean Association For Science Education
• /
• v.29 no.8
• /
• pp.848-860
• /
• 2009

This study examined the characteristics of scientists' writing on the laboratory reports written in the authentic open inquiry, and explored the possibility that the class discussion after the inquiries could influence the laboratory report writing. The samples were 131 10th graders in a science high school in Seoul. The control group (n=45) practiced traditional school science inquiries, the experimental group 1 (n=43) practiced the authentic open inquiries, and the experimental group 2 (n=43) practiced the authentic open inquiries and the class discussion after the laboratory activities. Their laboratory reports were analyzed into three parts - prediction (prediction with background and apposite description), data analysis (data transformation and critical analysis), and conclusion (objective description based on evidence). The frequency of the characteristics of scientist's writing in the experimental group was higher than the control group. Particularly, the differences of the prediction with background (p<.01) and the critical analysis of data (p<.05) were statistically significant. However, the frequency of writing the conclusion based on evidence was very low in all of the three groups. The result from comparing descriptions of reports showed that the writing prediction in experimental groups were more elaborate, and the data transformation in experimental groups were more correct, and the evaluation to data in experimental groups were more critical than the control group. And the descriptions of the critical evaluation to data and the finding flaw in methods were found in experimental groups 2, indicating that the class discussion can stimulate students' scientific thinking.