• Journal of the Korea Society for Simulation
• /
• v.33 no.2
• /
• pp.1-11
• /
• 2024

A cyber-physical system is a technology that connects the physical systems of a manufacturing environment with a cyber space to enable simulation. One of the major challenges in this technology is the seamless communication between these two environments. In complex manufacturing processes, it is crucial to adapt to various protocols of manufacturing equipment and ensure the transmission and reception of a large volume of data without delays or errors. In this study, we propose a method for constructing agent models for real-time simulation-capable cyberphysical systems. To achieve this, we design data collection units as independent agent models and effectively integrate them with existing simulation tools to develop the overall system architecture. To validate the proposed structure and ensure reliability, we conducted empirical testing by integrating various equipment from a real-world smart microfactory system to assess the data collection capabilities. The experiments involved testing data delay and data gaps related to data collection cycles. As a result, the proposed approach demonstrates flexibility by enabling the application of various internal data collection methods and accommodating different data formats and communication protocols for various equipment with relatively low communication delays. Consequently, it is expected that this approach will promote innovation in the manufacturing industry, enhance production line efficiency, and contribute to cost savings in maintenance.

• Information Systems Review
• /
• v.20 no.1
• /
• pp.159-177
• /
• 2018

With an extensive proliferation of information and communication technology, the volume and amount of digital information collected and utilized on the Internet have been increasing rapidly. Also on the rapid rise are side effects such as unintended breach of accumulated personal information and consequent invasion of personal privacy. Informational self-determination is rarely practiced, despite various states' legal efforts to redress data subjects' damage. Personal health information, in particular, is a subcategory of personal information where informational self-determination is hardly practiced enough. The observation is contrasted with the socio-economic inconvenience that may follow due to its sensitive nature containing individuals' physical and health conditions. This research, therefore, reviews factors of self-determination on personal health information while referring to the protection motivation theory (PMT), the long-time framework to understand personal information protection. Empirical analysis of 200 data surveyed reveals threat-appraisal (perceived vulnerability and perceived severity of threats) and coping-appraisal (perceived response effectiveness), in addition to individual levels of concern regarding provided personal health information, influence self-determination to protect personal health information. The research proposes theoretical findings and practical suggestions along with reference for future research topics.

• Journal of Korea Water Resources Association
• /
• v.57 no.5
• /
• pp.321-332
• /
• 2024

Understanding the status of surface cover in riparian zones is essential for river management and flood disaster prevention. Traditional survey methods rely on expert interpretation of vegetation through vegetation mapping or indices. However, these methods are limited by their ability to accurately reflect dynamically changing river environments. Against this backdrop, this study utilized satellite imagery to apply the Random Forest method to assess the distribution of vegetation in rivers over multiple years, focusing on the Naeseong Stream as a case study. Remote sensing data from Sentinel-2 imagery were combined with ground truth data from the Naeseong Stream surface cover in 2016. The Random Forest machine learning algorithm was used to extract and train 1,000 samples per surface cover from ten predetermined sampling areas, followed by validation. A sensitivity analysis, annual surface cover analysis, and accuracy assessment were conducted to evaluate their applicability. The results showed an accuracy of 85.1% based on the validation data. Sensitivity analysis indicated the highest efficiency in 30 trees, 800 samples, and the downstream river section. Surface cover analysis accurately reflects the actual river environment. The accuracy analysis identified 14.9% boundary and internal errors, with high accuracy observed in six categories, excluding scattered and herbaceous vegetation. Although this study focused on a single river, applying the surface cover classification method to multiple rivers is necessary to obtain more accurate and comprehensive data.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.24 no.3
• /
• pp.77-85
• /
• 2024

In this dissertation, a we designed and implemented a patrol robot that integrates a thermal imaging camera, speed dome camera, PTZ camera, radar, lidar sensor, and smartphone. This robot has the ability to monitor and respond efficiently even in complex environments, and is especially designed to demonstrate high performance even at night or in low visibility conditions. An orbital movement system was selected for the robot's mobility, and a smartphone-based control system was developed for real-time data processing and decision-making. The combination of various sensors allows the robot to comprehensively perceive the environment and quickly detect hazards. Thermal imaging cameras are used for night surveillance, speed domes and PTZ cameras are used for wide-area monitoring, and radar and LIDAR are used for obstacle detection and avoidance. The smartphone-based control system provides a user-friendly interface. The proposed robot system can be used in various fields such as security, surveillance, and disaster response. Future research should include improving the robot's autonomous patrol algorithm, developing a multi-robot collaboration system, and long-term testing in a real environment. This study is expected to contribute to the development of the field of intelligent surveillance robots.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.24 no.3
• /
• pp.55-61
• /
• 2024

In a hybrid architecture that combines the technological advantages of P2P(peer-to-peer) and cloud computing, it is possible to efficiently supply resources and allocate loads. In other words, by appropriately utilizing the processing power of the players constituting P2P as well as the server in the cloud computing environment, MMOG(Massively Multiplayer Online Game) can be configured that considers the scale of economic cost and service quality. In fact, the computing power and communication bandwidth of servers in the cloud are important demand-based resources. The more it is used when renting, the higher the cost, while the quality of service improves. On the other hand, if the player's processing power is utilized a lot, the quality of service deteriorates relatively while the economic cost decreases. In this paper, a bandwidth adjustment technique between servers and players for MMOG based on this hybrid structure is described. When the number of players running at the same time increases, the players' actions are appropriately distributed to servers and players to effectively utilize the server's computing power and communication volume. Simulation results show that in the MMOG based on cloud and P2P hybrid architecture, the bandwidth of the server is proportionally decreased as the bandwidth directly handled by players is increased.

• The Journal of the Acoustical Society of Korea
• /
• v.43 no.1
• /
• pp.103-111
• /
• 2024

Axial-flow fans are used to transport fluids in relatively low-pressure flow regimes, and a variety of design variables are employed. The tip geometry of an axial fan plays a dominant role in its flow and noise performance, and two of the most prominent flow phenomena are the tip vortex and the tip leakage vortex that occur at the tip of the blade. Various studies have been conducted to control these three-dimensional flow structures, and winglet geometries have been developed in the aircraft field to suppress wingtip vortices and increase efficiency. In this study, a numerical and experimental study was conducted to analyze the effect of winglet geometry applied to an axial fan blade for an air conditioner outdoor unit. The unsteady Reynolds-Averaged Navier-Stokes (RANS) equation and the FfocwsWilliams and Hawkings (FW-H) equation were numerically solved based on computational fluid dynamics techniques to analyze the three-dimensional flow structure and flow noise numerically, and the validity of the numerical method was verified by comparison with experimental results. The differences in the formation of tip vortex and tip leakage vortex depending on the winglet geometry were compared through a three-dimensional flow field, and the resulting aerodynamic performance was quantitatively compared. In addition, the effect of winglet geometry on flow noise was evaluated by numerically simulating noise based on the predicted flow field. A prototype of the target fan model was built, and flow and noise experiments were conducted to evaluate the actual performance quantitatively.

• The Korean Journal of Archival Studies
• /
• no.79
• /
• pp.343-387
• /
• 2024

Electronic records, characterized by their inherent volatility and instability, necessitate sustainable preservation measures to ensure their long-term accessibility. The National Archives of Korea has instituted a selection system for preservation formats tailored predominantly for document-type electronic records. However, this system falls short in accommodating other record types such as audiovisual records. This study endeavors to broaden the applicability of the existing system, with a concentrated focus on image-type electronic records, and to formulate foundational guidelines for their long-term preservation. In South Korea, image-type electronic records rank as the second most prevalent category following document-type. The image-type electronic records are the most basic form of audio-visual records, and research on this lays the foundation for future discussions on other audio-visual records. Consequently, this research has led to the development of a selection system for preservation formats specifically for image-type electronic records. This system is designed to facilitate the prompt and efficient evaluation of preservation format suitability, even in the context of emerging image formats. The efficacy of this system was validated through its application to extant image formats, resulting in the selection of TIFF, JFIF, and PNG as the optimal preservation formats. The outcomes of this study offer valuable insights and practical reference points for future preservation format evaluations within the field of electronic record management.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.3
• /
• pp.199-207
• /
• 2024

Today, AI image creation technology is being expanded and utilized across industries. Accordingly, various AI image creation programs optimized for the fashion industry are being developed and commercialized. In this study, we compared and analyzed the visual characteristics of fashion images created by AI image creation programs such as Playground, Midjourney, and The New Black to identify the characteristics of each program and point out areas where each program can be used and problems. The results are as follows: First, while Playground and Midjourney intuitively applied the contents of the command to create images that were different from actual fashion trends, Dannew Black created images that were relatively similar to fashion trends. Second, while Playground separates or combines images corresponding to the command content, Midjourny tends to create new images by adding and fusing various details. Third, in Playground, colors not included in the command appear randomly, and in The New Black, colors not included in the command appear coordinated, and Midjourney generates the color specified in the command relatively accurately. In conclusion, Midjourney can be used when seeking inspiration for developing unique and creative fashion designs, and The New Black can be helpful in referencing fashion trends or fashion styling. On the other hand, playgrounds can be somewhat confusing when it comes to color creation, so this is something to be careful about. It is expected that AI image creation tools can be used more efficiently in fashion design development.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.17 no.3
• /
• pp.121-129
• /
• 2024

The rapid advancement of digital technology and the COVID-19 pandemic have significantly accelerated the growth of online commerce, highlighting the need for support mechanisms that enable small business owners to effectively respond to these market changes. In response, this paper presents a foundational technology leveraging the Online to Offline (O2O) strategy to automatically capture products displayed on retail shelves and utilize these images to create virtual stores. The essence of this research lies in precisely identifying and recognizing the location and names of displayed products, for which a single-class-targeted, lightweight model based on YOLOv8, named ESD-YOLOv8, is proposed. The detected products are identified by their names through feature-point-based technology, equipped with the capability to swiftly update the system by simply adding photos of new products. Through experiments, product name recognition demonstrated an accuracy of 74.0%, and position detection achieved a performance with an F2-Score of 92.8% using only 0.3M parameters. These results confirm that the proposed method possesses high performance and optimized efficiency.

• Korean Journal of Environmental Biology
• /
• v.41 no.4
• /
• pp.370-385
• /
• 2023

Cyanobacterial harmful algal blooms (Cyano-HABs) are an international environmental problem that negatively affects the ecosystem as well as the safety of water resources by discharging cyanotoxins. In particular, the discharge of microcystins (MCs), a highly toxic substance, has been studied most actively, and various water treatment methods have been proposed for this purpose. In this paper, we reviewed adsorption technology, which is recognized as the most feasible, economical, and efficient method among suggested treatment methods for removing MCs. Activated carbons (AC) are widely used adsorbents for MCs removal, and excellent MCs adsorption performance has been reported. Research on alternative adsorption materials for AC such as biochar and biosorbents has been conducted, however, their performance was lower compared to activated carbon. The impacts of adsorbent properties(characteristics of pore surface chemistry) and environmental factors (solution pH, temperature, natural organic matter, and ionic strength) on the MCs adsorption performance were also discussed. In addition, toward effective control of MCs, the possibility of the direct removal of harmful cyanobacteria as well as the removal of dissolved MCs using adsorption strategy was examined. However, to fully utilize the adsorption for the removal of MCs, the application and optimization under actual environmental conditions are still required, thereby meeting the environmental and economic standards. From this study, crucial insights could be provided for the development and selection of effective adsorbent and subsequent adsorption processes for the removal of MCs from water resources.