• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.221-229
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• 2023

Recently, Grid-forming(GFM) converter, which offers features such as virtual inertia, damping, black start capability, and islanded mode operation in power systems, has gained significant attention. However, in low-voltage microgrids(MG), it faces challenges due to the coupling phenomenon between active and reactive power caused by the low line impedance X/R ratio and a non-negligible power angle. This power coupling issue leads to stability and performance degradation, inaccurate power sharing, and control parameter design problems for GFM converters. Therefore, this paper serves as a review study on not only control methods associated with GFM converters but also power decoupling techniques. The aim is to introduce promising control methods and enhance accessibility to future research activities by providing a critical review of power decoupling methods. Consequently, by facilitating easy access for future researchers to the study of power decoupling methods, this work is expected to contribute to the expansion of distributed power generation.

• Journal of Ocean Engineering and Technology
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• v.37 no.6
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• pp.247-255
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• 2023

Interference and collisions often occur in the loading process at shipyards. Existing simulation methods focus primarily on resource processes and schedules, and there is a lack of real-time reflection in the complex and highly variable loading process. This study aims to develop a spatial environment incorporating real-time product data, such as hulls, and confirms its effectiveness by simulating various construction scenarios. As a method, a near real-time spatial environment based on broadband laser scanning was established, with the situation of loading heavy cargo assumed when converting an existing ship into an LNG dual-fuel propulsion ship. A case study simulation of near-real-time cargo loading processes was then conducted using Unity 3D to confirm the interference and collision risks within the spatial environment. The results indicated that interference occurred in structures previously not identified in the design data, and a collision occurred during the loading object erection phase. The simulation confirmed that the identification of interference and collision risks during the erection phase highlights the need for a relocation or removal process of potential hazards before erection takes place. An improved erection simulation that integrates near real-time data could effectively prevent interference and collision risks.

• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.2
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• pp.193-210
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• 2024

The portrait featuring Jo Ban(1341-1401), a scholar-official from the late Goryeo and early Joseon period, and his wife is the oldest surviving couple portrait in Korea. It is of great value in uncovering the clothing culture of the period given the limited number of historical artifacts and records. This study examines the historical clothing and textile patterns of Jo Ban's wife and reproduces them using 3D fashion design software program CLO. She wears jokduri, chima, and baeja over layers of jeogori, a mixture of traditional Korean and Chinese styles. Her clothing illustrates eight patterns-one flower, five geometric, and two cloud. Records and relics of similar periods show that flower and geometric patterns in her clothing follow the prevailing styles of Goryeo, while the cloud patterns are representative of early Joseon. These details are used to reproduce six different styles of Jo Ban's wife with CLO tools. Various visualizations of textile patterns are applied to materials, generating a more realistic look than her existing 3D character created with the portrait. Results of this study are expected to help promote the use of Goryeo clothing and patterns in numerous designs and enhance intuitive understanding of Goryeo clothing based on 3D visualization.

• Journal of Advanced Navigation Technology
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• v.27 no.6
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• pp.788-797
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• 2023

In this paper, we introduced a test environment to test a vision-aided navigation system, as an alternative navigation system when global positioning system (GPS) is unavailable, for vertical take-off and landing (VTOL) unmanned aerial system. It is efficient to use a virtual environment to test and evaluate the vision-aided navigation system under development, but currently no suitable equipment has been developed in Korea. Thus, the proposed test environment is developed to evaluate the performance of the navigation system by generating input signal modeling and simulating operation environment of the system, and by monitoring output signal. This paper comprehensively describes research procedure from derivation of requirements specifications to hardware/software design according to the requirements, and production of the test environment. This test environment was used for evaluating the vision-aided navigation algorithm which we are developing, and conducting simulation based pre-flight tests.

• Journal of the Korea Society of Computer and Information
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• v.29 no.3
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• pp.83-90
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• 2024

In this paper, we propose a solution to apply a proximity voice dialog system to voice dialog technology, one of the interaction systems in multimedia environments. A voice dialog between multiple users in a multimedia space is designed by adjusting the volume of the voice according to the distance between the user avatars and muting the user who is beyond the audible distance. The main feature of this research is a reliable UDP-based active server system that delivers low-quality voice data to users who are far away based on distance and does not transmit voice data to users who enter the inaudible area for economic development. The performance of the proposed system was measured in a previously completed project based on the Unity game engine, and it is expected that the system proposed in this research will be actively used in environments that provide interaction between multiple users such as met averse content and real-time battle action games.

• Journal of the Korea Society of Computer and Information
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• v.29 no.3
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• pp.91-98
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• 2024

In this paper, we present a particle-grid blending framework based on a geometric approach to efficiently represent opaque ice spheres with air bubbles. The water temperature is diffused through the grid and the air bubbles represented inside the ice through the particles. To solve the problem of previous methods that generate noisy dissolved air fields, we use levelsets to lighten the algorithm, i.e., the number of active particles and the initial amount of dissolved oxygen can be used to efficiently control the termination conditions of heat diffusion. We also extend the previous dissolved air field method, which only computes near air bubbles, to transparent regions to represent realistic ice spheres, and introduce a levelset-based approach to accurately compute the orientation of particles. As a result, the method presented in this paper is about three times faster than the existing methods and shows visually improved visualization of opaque ice spheres, which can be used in the field of representing physical virtual ice forms.

• Journal of Information Technology Applications and Management
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• v.30 no.1
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• pp.115-126
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• 2023

In various fields such as art, design, music, film, sports, games, and fashion, NFTs (Non-Fungible Tokens) are creating new economic value through trading platforms dedicated to NFT art and content. In this article, I analyze the current state of blockchain technology and NFT art content in the context of an expanding market for blockchain-based NFT art content in the metaverse. I also propose several tasks based on the economic and industrial logic of technological innovation. The first task proposed is to integrate cultural arts on blockchain, metaverse, and NFT platforms through digital innovation, instead of separating or distinguishing between creative production and consumption. Before the COVID-19 pandemic, there was a clear separation between creators and consumers. However, with the rise of Web 3.0 platforms, any user can now create and own their own content. Therefore, it is important to promote a collaborative and integrated approach to cultural arts production and consumption in the blockchain and metaverse ecosystem. The second task proposed is to align the legal framework with blockchain-based technological innovation. The enactment and revision of relevant laws should focus on promoting the development of the NFT trading platform ecosystem, rather than merely regulating it for user protection. As blockchain-based technology continues to evolve, it is important that legal systems adapt to support and promote innovation in the space. This shift in focus can help create a more conducive environment for the growth of blockchain-based NFT platforms. The third task proposed is to integrate education on digital arts, including metaverse and NFT art contents, into the current curriculum. This education should focus on convergence and consilience, rather than merely mixing together humanities, technology, and arts. By integrating digital arts education into the curriculum, students can gain a more comprehensive understanding of the potential of blockchain-based technologies and NFT art. This article examines the digital technological innovation such as blockchain, metaverse, and NFT from an economic and industrial point of view. As a limitation of this research, the critical mind such as philosophical thinking or social criticism on technological innovation is left as a future task.

• Science of Emotion and Sensibility
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• v.27 no.1
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• pp.81-92
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• 2024

This study analyzed augmented reality (AR) technology use in the fashion industry by classifying them based on product, wearer, space, purpose, and use. In this study, 76 cases of AR technology use in the fashion industry that were analyzed in domestic and foreign portals (Google, Naver, etc.) and research articles were collected and analyzed. The study found that in AR technology cases, the dimensions of the product, wearer, and space were utilized in various ways, including real, virtual, and their combination. AR technology was used diversely and creatively in design and product development, marketing and publicity, fashion shows, try-ons, online and offline sales and distribution, etc. Through AR technology, the categories of fashion products, concept of fashion shows, try-on methods, marketing and promotional tools, and sales tools are expanded more creatively from the existing framework. For inclusive growth within the fashion industry in the future, the national government, local governments, and large corporations should develop measures in bridging the digital gap, such as the use of AR technology according to technological readiness, capital, and age.

• Advances in concrete construction
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• v.17 no.2
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• pp.75-92
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• 2024

High Strength steel reinforced Reactive Powder Concrete (RPC) Beam is a new type of beams which has evident advantages than the conventional concrete beams. However, there is limited research on the shear bearing capacity of high-strength steel reinforced RPC structures, and there is a lack of theoretical support for structural design. In order to promote the application of high-strength steel reinforced RPC structures in engineering, it is necessary to select a shear model and derive applicable calculation methods. By considering the shear span ratio, steel fiber volume ratio, longitudinal reinforcement ratio, stirrup ratio, section shape, horizontal web reinforcement ratio, stirrup configuration angle and other variables in the shear test of 32 high-strength steel reinforced RPC beams, the applicability of three theoretical methods to the shear bearing capacity of high-strength steel reinforced RPC beams was explored. The plasticity theory adopts the RPC200 biaxial failure criterion, establishes an equilibrium equation based on the principle of virtual work, and derives the calculation formula for the shear bearing capacity of high-strength steel reinforced RPC beams; Based on the Strut and Tie Theory, considering the softening phenomenon of RPC, a failure criterion is established, and the balance equation and deformation coordination condition of the combined force are combined to derive the calculation formula for the shear bearing capacity of high-strength reinforced RPC beams; Based on the Rankine theory and Rankine failure criterion, taking into account the influence of size effects, a calculation formula for the shear bearing capacity of high-strength reinforced RPC beams is derived. Experimental data is used for verification, and the results are in good agreement with a small coefficient of variation.

• Archives of design research
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• v.19 no.4 s.66
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• pp.61-70
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• 2006

The functions and roles in the various fields of modern society are changing into the unified and multiplex structure, which is simultaneous and virtual communication environments beyond physical space and time, by the digital IT technology. The urban traffic system is also being intellectualized in order to solve urban traffic problems and convenient services by using digital IT technology. The bus, which is the one of the most common public transportation, are suffering in the decrease of bus service quality and the bus passengers rate because of the development of other public transportation systems such as the subway and electric railway and by rapidly increasing private cars. By recognizing these problems, many domestic and overseas cities are promoting to introduce the Bus Information System (BIS) to improve service quality of buses through the intelligent traffic system. According to the construction of this new information system called the Bus Information System (BIS), the new bus stop configuration system and design plans are being required to solve the existing bus stop information system. Therefore, this research was conducted to suggest an effective BIS configuration system plan and synthetic design goals based on the investigation the problems of the information system and the BIS configuration system for Busan city. Also, this research are conducted the below actions as follows: First, the literature survey was conducted, such as theoretical documents on the bus stop and the Bus Information System(BIS), Also, the design trend of the BIS was examined through domestic and overseas BIS cases studies. Scondly, the problems related to the information system in Busan city bus stops were investigated to investigate the present state and problems of the Bus Information System (BIS). Finally, as a result of this research, the effective BIS configuration system plan and design approach methods of bus stops were proposed for by Busan city based on the above investigation results.