• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.1
• /
• pp.61-73
• /
• 2021

Metaheuristic search methods have been developed to solve problems with a range of purpose functions in situations lacking information and time constraints. In this study, the Hybrid Vision Correction Algorithm (HVCA), which enhances the performance of the Vision Correction Algorithm (VCA), was developed. The HVCA has applied two methods to improve the performance of VCA. The first method changes the parameters required by the user for self-adaptive parameters. The second method, the CGS structure of the Exponential Bandwidth Harmony Search With a Centralized Global Search (EBHS-CGS), was added to the HVCA. The HVCA consists of two structures: CGS and VCA. To use the two structures, a method was applied to increase the probability of selecting the structure with the optimal value as it was performed. The optimization problem was applied to determine the performance of the HVCA, and the results were compared with Harmony Search (HS), Improved Harmony Search (IHS), and VCA. The HVCA improved the number of times to find the optimal value during 100 repetitions compared to HS, IHS, and VCA. Moreover, the HVCA reduced the Number of Function Evaluations (NFEs). Therefore, the performance of the HVCA has been improved.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.3
• /
• pp.460-469
• /
• 2021

Many people today suffer from stress originated from diseases, daily life, workplace, or environmental pollution. People want a comfortable and stable life along with physical and mental relaxation. As the number of people pursuing a comfortable life increases, terms of well-being and wellness have become more common, and wellness-related industries are also developing. Among the wellness and well-being industries, the wellness entertainment contents are one of the highest growing industries. This study aims to investigate how wellness contents contribute to improving the psychological well-being level of users through the mediating effect of telepresence in online. Specifically, this study suggests a hypothesized research model on the influence of online wellness entertainment content, which consists of sensory-, emotional-, and cognitive-attributes, on telepresence, followed by psychological well-being and word-of-mouth. With an empirical test using data on the experience of meditation app experience for 305 people, the result showed that the hypotheses in the research model were supported. The result of this study showed that wellness content induces users' telepresence and word-of-mouth, suggesting that wellness contents are needed to develop into a profit model rather than being limited to simple mental and physical stability.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.1
• /
• pp.47-52
• /
• 2021

Recently, the share of wind power in energy markets has sharply increased with the active development of renewable energy internationally. In particular, large-scale wind farms are being developed far from the coast to make use of abundant wind resources and to reduce noise pollution. In addition to the electromagnetic interference (EMI) caused by offshore wind farms to coastal or air surveillance radars, it is necessary to investigate the EMI on global maritime distress and safety system (GMDSS) communications between ship and coastal stations. For this purpose, this study investigates whether the transmitted field of MF/HF band from a ship would be subject to interference or attenuation below the threshold at a coastal receiver. First, using geographic information system digital maps and 3D CAD models of wind turbines, the area of interest is electromagnetically modeled with patch models. Although high frequency analysis methods like Physical Optics are appropriate to analyze wide areas compared to its wavelength, the high frequency analysis method is first verified with an accurate low frequency analysis method by simplifying the surrounding area and turbines. As a result, the received wave power is almost the same regardless of whether the wind farms are located between ships and coastal stations. From this result, although wind turbines are large structures, the size is only a few wavelengths, so it does not interfere with the electric field of MF/HF distress communications.

• Journal of Korea Water Resources Association
• /
• v.53 no.12
• /
• pp.1193-1201
• /
• 2020

This study aims to develop a regression model that estimates a low-flow index that can be applied to ungauged basins. A total of 30 midsized basins in South Korea use long-term runoff data provided by the National Integrated Water Management System (NIWMS) to calculate average low-flow, average minimum streamflow, and low-flow index duration and frequency. This information is used in the correlation analysis with 18 basin factors and 3 climate change factors to identify the basin area, average basin altitude, average basin slope, water system density, runoff curve number, annual evapotranspiration, and annual precipitation in the low-flow index regression model. This study evaluates the model's accuracy by using the root-mean-square error (RMSE) and the mean absolute error (MAE) for 10 ungauged, verified basins and compares them with the previous model's low-flow calculations to determine the effectiveness of the newly developed model. Comparative analysis indicates that the new regression model produces average low-flow, attributed to the consideration of varied basin and hydrologic factors during the new model's development.

• Journal of Korean society of Dental Hygiene
• /
• v.21 no.4
• /
• pp.337-348
• /
• 2021

Objectives: To determine the usefulness of MiriChek^TM Oral Bacter as compared to traditional clinical methods in the periodontal assessment of dogs with and without periodontitis. Methods: In this study, 61 dogs were clinically examined using the MiriChek^TM Oral Bacter test kit, and information regarding breed, age (months), sex, weight, presence of disease, and periodontitis stage was recorded. The test used a sample of supragingival plaque from the upper left premolar of the dogs. Results: This study included 30 and 31 dogs with and without periodontitis, respectively. Periodontitis was more common in older dogs than in younger dogs. The average positive and negative sensitivity rates of the MiriChek^TM Oral Bacter test kit were 73.3% and 80.7%, respectively, and were both strongly correlated with the severity of periodontitis. Conclusions: The findings of this study encourage the use of new diagnostic assist test kits, such as MiriChek^TM Oral Bacter, for appropriately detecting and diagnosing periodontal disease in dogs.

• Informatization Policy
• /
• v.28 no.4
• /
• pp.54-75
• /
• 2021

The right to data portability needs to be introduced to strengthen the self-control of data subjects and promote personal data use. However, the right to data portability constitutes a high risk of invasion of privacy of data subjects and may infringe on the property rights of data controllers, so careful and thorough design is warranted. The right to data portability can intensify the concentration and monopoly of personal data, result in problems of overseas transfer of personal data held by public institutions, and enrich only the profits of giant platforms by burdening the data subject with high transfer cost. By contrast, SMEs are more likely to endure a personal data deprivation. From the proposed amendment to the Personal Data Protection Act are raised various legal issues such as. i) Whether to include inferred/derived data, personal data held by public institutions, activity data, sensitive data, and personal data of third parties within the scope of data portability; ii) whether SMEs are included in the data porting organization; iii) whether to exclude SMEs or large platforms from the scope of the data receiving organization; iv) Whether to allow the right to transmit to other data controllers, v) Whether to allow the overseas transfer of personal data held by public institutions, vi) How to safely exercise the right to data portability, vii) the scope of responsibility and immunity of a data porting organization, etc. The purpose of this paper is to propose the direction for legislative action based on various legal issues related to data portability.

• The Korean Journal of Applied Statistics
• /
• v.35 no.4
• /
• pp.553-568
• /
• 2022

The Household Income and Expenditure Survey is a representative survey of Statistics Korea, which aims to measure and analyze national income and consumption levels and their changes by understanding the current state of household balances. Recently, the disconnection problem in these time series caused by the large-scale reorganization of the survey methods in 2017 and 2019 has become an issue. In this study, we model the characteristics of the time series in the Household Income and Expenditure Survey up to 2016, and use the modeling to compute forecasts for linking the expenditures in 2017 and 2018. In order to evenly reflect the characteristics across all expenditure item series and to reduce the impact of a specific forecast model, we synthesize a total of 8 models such as regression models, time series models, and machine learning techniques. In particular, the noteworthy aspect of this study is that it improves the forecast by using the optimal combination technique that can exactly reflect the hierarchical structure of the Household Income and Expenditure Survey without loss of information as in the top-down or bottom-up methods. As a result of applying the proposed method to forecast expenditure series from 2017 to 2019, it contributed to the recovery of time series linkage and improved the forecast. In addition, it was confirmed that the hierarchical time series forecasts by the optimal combination method make linkage results closer to the actual survey series.

• Journal of Korea Port Economic Association
• /
• v.37 no.4
• /
• pp.33-40
• /
• 2021

Currently, the shipping and port industries are implementing strategies to improve port processing capabilities through the expansion and efficient operation of port logistics resources to survive fierce competition with rapidly changing trends. The calculation of the port's processing capacity is determined by the loading and unloading equipment installed at the dock, and the port's processing capacity can be improved through various methods, such as additional deployment of logistics resources or efficient operation of resources in use. However, it is difficult to expect an improvement effect in a short period of time because the additional deployment of logistics resources is clearly limited in time is clear. Therefore, it is a feasible way to find an efficient operation method for resources being used to improve processing capacity. Domestic ports are also actively promoting informatization and digitalization with the development of the 4th industrial revolution technology. However, the calculation of the number of Y/T (Yard Tractor) assignments in the current unloading process depends on expert experience, and related previous studies also focus on the allocations of Y/T or Calculation of the total number of Y/T required. Therefore, this study analyzed the factors affecting the number of Y/T allocations using the loading and unloading information of incoming ships, and based on this, cluster analysis, regression analysis, and deep neural network(DNN) model were used.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.24 no.2
• /
• pp.171-182
• /
• 2022

InSAR (Interferometry SAR) technique is a technique that uses complex data to obtain phase difference information from two or more SAR image data, and enables high-resolution image extraction, surface change detection, elevation measurement, and glacial change observation. In many countries, research on the InSAR technique is being conducted in various fields of study such as volcanic activity detection, glacier observation in Antarctica, and ground subsidence analysis. In this study, a case of large ground settlement due to groundwater level drawdown during tunnelling was introduced, and ground settlement analyses using InSAR technique and numerical analysis method were compared. The maximum settlement and influence radius estimated by the InSAR technique and numerical method were found to be quite similar, which confirms the reliability of the InSAR technique. Through this case study, it was found that the InSAR technique reliable to use for estimating ground settlement and can be used as a key technology to identify the long-term ground settlement history in the absence of measurement data.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.4
• /
• pp.857-862
• /
• 2021

Recently, rapid climate change has had a significant impact on the bee ecosystem. The decrease in the number of bees and the change in the flowering period have a huge impact on the harvesting of beekeepers. Accordingly, attention is focused on smart beekeeping, which introduces IoT technology to beekeeping. According to the characteristics of beekeeping, it is impossible to continuously observe the beehive in the hive with the naked eye, and the condition of the hive is mostly dependent on knowledge from experience. Although a system that can measure partly through sensors such as temperature/humidity change inside the hive and measurement of the amount of CO2 is applied, there is no research on measuring the movement path and amount of movement of bees inside the beehive. Part of the migration of honeybees inside the hive can provide basic information to predict the most important cleavage time in beekeeping. In this study, we propose a device that detects the movement path of bees and measures and records data entering and exiting the hive in real time. The device proposed in this study was developed according to the honeycomb standard of the existing beehive so that beekeeping farms could use it. The development method used a photodetector that can detect the movement of bees to configure 16 movement paths and to detect the movement of bees in real time. If the measured honeybee movement status is utilized, the problem of directly observing the colony with the naked eye in order not to miss the swarming time can be solved.