• Journal of Korean Academy of Nursing
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• v.53 no.3
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• pp.359-369
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• 2023

Purpose: This study evaluated the internal structure (structural validity, internal consistency, and measurement invariance) of the Health-Related Quality of Life Instrument with Eight Items (HINT-8), developed to measure Korean people's health-related quality of life. Methods: A secondary analysis was conducted using data from the Korea National Health and Nutrition Examination Survey, involving 6,167 adults aged over 18 years. The structural validity of the HINT-8 was assessed using exploratory graph analysis and confirmatory factor analysis. Internal consistency and measurement invariance were analyzed using McDonald's omega (ω) and multigroup confirmatory factor analysis, respectively. Results: The HINT-8 had a single dimension and good internal consistency (ω =.804). The one-dimension HINT-8 exhibited matric invariance but not scalar invariance across sociodemographic groups (sex, age, education, and marital status). Further, it exhibited scalar or partial scalar invariance across medical condition groups (hypertension, diabetes, depressive symptoms, and cancer). Conclusion: The study finds that the HINT-8 demonstrated satisfactory structural validity and internal consistency, indicating its suitability for practice and research. However, the HINT-8 scores cannot be compared across different groups regarding sex, age, education, and marital status, as the interpretation varies within each sociodemographic category. Conversely, interpretation of the HINT-8 is consistent for individuals with and without hypertension, diabetes, depressive symptom, and cancer.

• Journal of Fashion Business
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• v.26 no.2
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• pp.129-142
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• 2022

The purpose of this study is to develop socks to check the range of ankle movement during squats for men in their late 20s. Sensors of 6, 8, and 12 mm were selected, and each sample was impregnated 1 to 3 times. It was prepared using a CNT dispersion, and the GF value was measured using UTM. Among them, the sample with 2 impregnation showed the best GF value. As a result of applying each sample to the socks, the 12 mm sensor was wider than the area of the Achilles tendon, resulting in noise, and the 8 mm sensor was higher than the tensile strength of the socks, resulting in a decrease in the graph. Therefore, testing was performed using a 6 mm sensor. In order to determine the effectiveness of the sensor, the normal operating range was checked through squats, and significant changes were confirmed when the operating range was checked again through squats by performing operations that can increase the operating range through Gastrocnemius, Soleus stretching, and low lunge. Using the results of this study, it is expected that the average value of the ankle movement range of the user is checked prevent injury, to be provided as basic data for the production of shoe products and the promotion of physical health.

• Information Systems Review
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• v.19 no.1
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• pp.49-74
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• 2017

The development of smart devices has affected employees' working environments and their lives. However, using smart devices is causing employees to experience technostress. This study aims to investigate the effects of technostress in using smart devices on usage intention in an organization. Moreover, the study investigates the effect of employees' stress-coping methods on the intention to use smart devices. This study posits familiarity, use innovativeness, role ambiguity, system vulnerability, technological limitation, and ubiquity as the antecedents of technostress. Data collected from 317 users who have experience in using smart devices in organizations are empirically tested against a research model using the PLS graph. Analysis results show that role ambiguity, system vulnerability, and technological limitation significantly influence technostress. Moreover, users take up emotion-focused coping behaviors because of technostress. Emotion-focused coping behaviors affect usage intention in organizations. However, technostress and problem-focused coping behaviors do not directly affect usage intention in organizations.

• Journal of Wind Energy
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• v.15 no.1
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• pp.69-81
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• 2024

In order to understand water depth distribution in the waters of the southwestern sea offshore wind power demonstration complex, field observations were conducted using a multi-beam echosounder from before construction (2018.2) to operation (2022.8). After data processing and correction of the observed depth, cross-sectional analysis was performed to calculate the maximum water depth value, and time phase analysis was performed using the maximum water depth value. The maximum water depth change rate over time tended to gradually decrease, and there was little difference in the rate of change before the construction of the wind turbine foundation structure, and the rate of change was rapid when the foundation structure was under construction. As a result of time phase analysis, the rate of change of the first (2018.02) and the second (2018.05) showed a rate between -6.27 and -4.13, on average, as the rate of change before the construction of the offshore wind farm, and there was no difference between the first and second rates. The third (2018.11) rate of change was -4.25 to -1.82, and the fourth (2019.04) rate of change was -2.34 to -1.22, and the rate of change increased rapidly after the third time. The fifth (2019.07) rate of change was -2.11 to -1.31, the sixth (2021.05) rate of change was -2.09 to -1.28, and the seventh (2022.08) was -2.11 to -1.22 rate of change, and after the rate of change reached some extent, the change was analyzed in an insufficient graph.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.4
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• pp.99-106
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• 2024

The problem of the bridges(Hasjiwokakero, Hasi) puzzle, which connects the bridge(edge) required by the island(vertex) without crossing the horizontal and vertical straight bridges except for the diagonal to form a connected network, is a barren ground for research without any related research. For this problem, there is no algorithm that presents a generalized exponential time brute-force or branch-and-bound method. This paper obtained the initial solution of the lattice graph by drawing a grid without diagonal lines for a given BP, removing unnecessary edges, and supplementing essential bridges. Next, through insufficient island pair path matching, the method of adding insufficient edges to the route and deleting the crossed surplus edges(bridges) was adopted. Applying the proposed algorithm to 24 benchmarking experimental data showed that accurate solutions can be obtained for all problems.

• Journal of Internet Computing and Services
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• v.25 no.4
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• pp.7-21
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• 2024

There are various machine learning techniques such as Reinforcement Learning, Deep Learning, Neural Network Learning, and so on. In recent, Large Language Models (LLMs) are popularly used for Generative AI based on Reinforcement Learning. It makes decisions with the most optimal rewards through the fine tuning process in a particular situation. Unfortunately, LLMs can not provide any explanation for how they reach the goal because the training is based on learning of black-box AI. Reinforcement Learning as black-box AI is based on graph-evolving structure for deriving enhanced solution through adjustment by human feedback or reinforced data. In this research, for mutually exclusive decision-making, Mutually Exclusive Learning (MEL) is proposed to provide explanations of the chosen goals that are achieved by a decision on both ends with specified conditions. In MEL, decision-making process is based on the tree-based structure that can provide processes of pruning branches that are used as explanations of how to achieve the goals. The goal can be reached by trade-off among mutually exclusive alternatives according to the specific contextual conditions. Therefore, the tree-based structure is adopted to provide feasible solutions with the explanations based on the pruning branches. The sequence of pruning processes can be used to provide the explanations of the inferences and ways to reach the goals, as Explainable AI (XAI). The learning process is based on the pruning branches according to the multi-dimensional contextual conditions. To deep-dive the search, they are composed of time window to determine the temporal perspective, depth of phases for lookahead and decision criteria to prune branches. The goal depends on the policy of the pruning branches, which can be dynamically changed by configured situation with the specific multi-dimensional contextual conditions at a particular moment. The explanation is represented by the chosen episode among the decision alternatives according to configured situations. In this research, MEL adopts the tree-based learning model to provide explanation for the goal derived with specific conditions. Therefore, as an example of mutually exclusive problems, employment process is proposed to demonstrate the decision-making process of how to reach the goal and explanation by the pruning branches. Finally, further study is discussed to verify the effectiveness of MEL with experiments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.8
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• pp.2253-2280
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• 2024

In the upcoming era of transportation, a groundbreaking technology, known as vehicle-to-everything (V2X) communication, is poised to redefine our driving experience and revolutionize traffic management. Real-time and secure communication plays a pivotal role in V2X networks, with the decision-making process being a key factor in establishing communication and determining malicious nodes. The proposed framework utilizes a directed acyclic graph (DAG) to facilitate real-time processing and expedite decision-making. This innovative approach ensures seamless connectivity among vehicles, the surrounding infrastructure, and various entities. To enhance communication efficiency, the entire roadside unit (RSU) region can be subdivided into various sub-regions, allowing RSUs to monitor and govern each sub-region. This strategic approach significantly reduces transaction approval time, thereby improving real-time communication. The framework incorporates a consensus mechanism to ensure robust security, even in the presence of malicious nodes. Recognizing the dynamic nature of V2X networks, the addition and removal of nodes are aligned. Communication latency is minimized through the deployment of computational resources near the data source and leveraging edge computing. This feature provides invaluable recommendations during critical situations that demand swift decision-making. The proposed architecture is further validated using the "veins" simulation tool. Simulation results demonstrate a remarkable success rate exceeding 95%, coupled with a significantly reduced consensus time compared to prevailing methodologies. This comprehensive approach not only addresses the evolving requirements of secure V2X communication but also substantiates practical success through simulation, laying the foundation for a transformative era in transportation.

• Journal of Space Technology and Applications
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• v.4 no.3
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• pp.220-231
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• 2024

This study deals with an experiment to measure ozone concentration in the atmosphere over the Korean Peninsula, Jeollabuk-do, using a helium balloon and analyze the change in atmospheric density based on the scale height. In the experiment, Arduino Uno was used to collect data and ozone concentration was measured using the MQ131 sensor. In addition, the BMP280 sensor was used to measure temperature and atmospheric pressure at various altitudes. The experimental results showed that the scale height of the atmosphere over the Korean Peninsula was 6,828.30 m, and the decreasing pattern of atmospheric density was confirmed based on this. In addition, by analyzing the graph of the measured ozone level, a phenomenon of a rapid decrease in the ozone level was observed between 8 km and 9 km altitude. These results can provide important information for understanding the atmospheric environment and ozone concentration changes and for environmental monitoring.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.11
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• pp.589-598
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• 2007

In the group communication which has multiple data streams and various access privileges, it is necessary to provide group access control. The group members having the same access privilege are classified into one class, and the classes form a hierarchy based on the access relations. Then each class is assigned to a secret key. In the previous schemes, a single logical key graph is constructed from the hierarchy and each member always holds all secret keys of the classes he can access in the proactive manner. Thus, higher-privileged members hold more keys then lower-privileged members. However, if the hierarchy is large, each member manages too many keys and the size of multicast message in rekeying increases in proportion to the size of the hierarchy. Moreover, most of the members access a small portion of multiple data streams simultaneously. Therefore, it is redundant to receive rekeying message and update the keys in which he is not currently interested. In this paper, we present a new key management scheme that takes a reactive approach in which each member obtains the key of a data stream only when he wants to access the stream. Each member holds and updates only the key of the class he belongs. If he wants to get the key of other class, he derives it from his key and the public parameter. Proposed scheme considerable reduces the costs for rekeying, especially in the group where access relations are very complex and the hierarchy is large. Moreover, the scheme has another advantage that it easily reflects the change of access relations.

• 한국정보교육학회:학술대회논문집
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• 2011.01a
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• pp.91-101
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• 2011

The purpose of this paper is to quickly identify school parents, teachers, students, community needs and opinions for curriculum organizing and the implementation of an online survey system for operating educational activities. Online survey system should be implemented based on Limesurvey to reduce costs and administrative costs. Limesurvery is available without the development of the separate program and offers the form of web-based template system, complete design, layout. Also, Limesurvey offers basic statistical analysis of survey data. Limesurvey can be executed by installing the program on a web hosting, typing database information. Limesurvey can be made a graph of the statistical results. Besides, Limesurvery can be stored in the form of HTML, Word, Excel, CSV Files and can be stured as basic datas for SPSS or PASW, R data, other statistical processing programs. If we could be operate Limesurvey in the form of open source-based survey program in elementary school, we could be reduced teacher's unnecessary work for statistics and overcame the problem of offline survey system.