• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.111-122
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• 2021

This study analyzed user reviews of Dongbaekjeon and Incheoneum app, which are representative local currencies in Korea, to identify the positive/negative factors of local currency users, and established a marketing strategy based on this. App user reviews were classified into positive and negative based on the star rating, and word cloud, topic modeling, and social network analysis were performed, respectively. As a result, in the negative reviews of Dongbaekjeon and Incheoneum, dissatisfaction with app use and card issuance appeared in common. In positive reviews, keywords such as 'local economy' and 'small business owners' along with satisfaction with 'cashback' appeared. It means that local currency users perceived that their consumption support local economy, and they felt satisfaction in using local currency. Based on the satisfaction/dissatisfaction factors identified as a result of the analysis of this study, we identified what needs to be improved and to be strengthened, and appropriate marketing strategies were established. The text mining method used in this study and research results can provide meaningful information about local currencies to public officials and marketers in charge of local currencies.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.12
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• pp.1859-1867
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• 2021

Multi LiDAR sensors are being mounted on autonomous vehicles, and a system to multi LiDAR sensors data is required. When sensors data is transmitted or processed to the main processor, a huge amount of data causes a load on the transport network or data processing. In order to minimize the number of load overhead into LiDAR sensor processors, only semantic data is transmitted through data comparison between frames in LiDAR data. When data from 4 LiDAR sensors are processed in a static environment without moving objects and a dynamic environment in which a person moves within sensor's field of view, in a static experiment environment, the transmitted data reduced by 89.5% from 232,104 to 26,110 bytes. In dynamic environment, it was possible to reduce the transmitted data by 88.1% to 29,179 bytes.

• Journal of Advanced Navigation Technology
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• v.26 no.5
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• pp.312-318
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• 2022

Currently, the Republic of Korea is facing the problem of a decrease in military service resources due to the demographic cliff, and is pursuing military restructuring and changes in the military force structure in order to respond to this. In this situation, the Army is pushing forward the deployment of a drone-bot combat system that will lead the future battlefield. The battlefield of the future will be changed into an integrated battlefield concept that combines command and control, surveillance and reconnaissance, and precision strike. According to these changes, unmanned combat system, including dronebots, will be widely applied to combat situations that are high risk and difficult for humans to perform in actual combat. In this paper, as one of the countermeasures to these changes, autonomous behavior software with a BDI architecture-based decision-making system was developed. The autonomous behavior software applied a framework structure to improve applicability to multiple models. Its function was verified in a PC-based environment by assuming that the target UAV is a battalion-level surveillance and reconnaissance UAV.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1189-1198
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• 2021

When performing remote tasks using robots in nuclear power plants, a 3D shape measurement system is advantageous in improving the efficiency of remote operations by easily identifying the current state of the target object for example, size, shape, and distance information. Nuclear power plants have high-radiation and underwater environments therefore the electronic parts that comprise 3D shape measurement systems are prone to degradation and thus cannot be used for a long period of time. Also, given the refraction caused by a medium change in the underwater environment, optical design constraints and calibration methods for them are required. The present study proposed a method for developing an underwater 3D shape measurement system with improved radiation tolerance, which is composed of commercial electric parts and a stereo camera while being capable of easily and readily correcting underwater refraction. In an effort to improve its radiation tolerance, the number of parts that are exposed to a radiation environment was minimized to include only necessary components, such as a line beam laser, a motor to rotate the line beam laser, and a stereo camera. Given that a signal processing circuit and control circuit of the camera is susceptible to radiation, an image sensor and lens of the camera were separated from its main body to improve radiation tolerance. The prototype developed in the present study was made of commercial electric parts, and thus it was possible to improve the overall radiation tolerance at a relatively low cost. Also, it was easy to manufacture because there are few constraints for optical design.

• Journal of Internet of Things and Convergence
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• v.8 no.4
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• pp.1-7
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• 2022

As the number of IoT devices increases, power management of the cluster head, which acts as a gateway between the cluster and sink nodes in the IoT network, becomes crucial. Particularly when the cluster head is a mobile wireless terminal, the power consumption of the IoT network must be minimized over its lifetime. In addition, the delay of information transmission in the IoT network is one of the primary metrics for rapid information collecting in the IoT network. In this paper, we propose a low-power buffer management algorithm that takes into account the information transmission delay in an IoT network. By forwarding or skipping received packets utilizing deep Q learning employed in deep reinforcement learning methods, the suggested method is able to reduce power consumption while decreasing transmission delay level. The proposed approach is demonstrated to reduce power consumption and to improve delay relative to the existing buffer management technique used as a comparison in slotted ALOHA protocol.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.3
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• pp.173-185
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• 2022

For the smooth implementation and success of smart city projects, it is necessary to recognize that there is a difference in the perception of value judgments or strategic goals among major stakeholders in the planning process. And it is necessary to aim the values and goals of smart cities through reconciliation of these differences. The two major stakeholders in the smart city development project are citizens group and government officials group. Government officials are in charge of establishing and implementing policies for smart city projects, and their value judgments and perceptions influence the policy direction. In these respects, government officials can be an important stakeholder group. Citizens are a group that includes ordinary residents and business owners who live in smart cities and are the ultimate users of infrastructure and facilities. This study investigated the importance perceptions of citizens and government officials, who are the major stakeholders, about the core values and strategic goals that the smart city project aims. Responses were collected using a structured questionnaire to which the AHP methodology was applied. And the priority of perceptions for constituent items was compared for each stakeholder group. Through the comparative analysis results, it was empirically confirmed that there is a difference in the values and goals pursued by the smart city project between stakeholder groups. As an empirical study on the stakeholders of the smart city project, this study is meaningful in contributing to the theoretical development in that it suggests that the conceptual structural model of the smart city strategy system presented in previous studies can be applied in practice.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.386-386
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• 2021

대기 중 온실가스 농도는 인간의 인위적 활동에 의해 증가하고 있으며, 이로 인하여 발생하는 기후변화는 극한 수문 사상에 상당한 영향을 미치고 있다. 특히, 기후변화로 인한 강수 특성의 변화는 홍수, 가뭄, 태풍 등과 같은 극한사상의 변화로 이어지며, 급격한 도시화와 복잡한 사회기반시설물 등과 맞물려 더욱 취약한 홍수위험 문제로 대두된다. 기후변화에 따른 미래의 불확실한 변화에 적응하기 위하여 다양한 기후모델들이 개발되었고, 기후변화와 관련된 많은 응용 연구들이 기후모델에서 모의된 자료를 기반으로 미래를 전망하고 있다. IPCC (Intergovernmental Panel on Climate Change) 제6차 평가보고서(The 6th Assessment Report: AR6)에서는 사회경제 구조의 변화를 반영한 공통사회경제경로 시나리오(Shared Socioeconomic Pathways, SSP) 개념을 도입하였다. SSP 시나리오는 사회경제 변화를 기준으로 기후변화에 대한 완화와 노력에 따라 5개의 시나리오로 구별된다. 기상청 기후정보포털(http://www.climate.go.kr/)에서는 4개 조합의 시나리오(SSP1-RCP2.6, SSP2-RCP4.5, SSP3-RCP7.0, SSP5-RCP8.5) 결과가 제공된다. 자료는 동아시아 지역에 대해 생산한 자료로 25km의 공간해상도를 가지고 있으며, 현재모의기간(1979-2014, S_HIST)과 미래시나리오기간(2015-2020, S_SSP)으로 구분된다. 본 연구에서는 전술한 SSP-RCP 시나리오 조합 중 SSP1-RCP2.6, SSP5-RCP8.5 조합을 이용하여 광주지역 극한강우의 미래 변화를 분석하였다. 시나리오 기반 강우자료의 통계적 특성 분석을 위해 연최대 자료를 추출하여 경향성 및 변동성 분석을 수행하였고, 광주지역 강우 자료에 내재된 특성 변화를 정량적으로 분석하였다.

• Korean Journal of Optics and Photonics
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• v.34 no.6
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• pp.283-288
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• 2023

We investigate the optical and electrical properties of silver nanofilms deposited on transparent substrates such as quartz, sapphire, and slide glass treated with (3-mercaptopropyl) trimethoxysilane (MPTMS). The effect of MPTMS treatment on physical properties is studied through scanning electron microscope (SEM) images, UV-visible transmission, and current-voltage measurements. The SEM images show morphology change of the silver nanofilm, and the UV-visible transmission spectra reveal that the localized surface-plasmon resonance effect is reduced due to the morphology change. These results imply that the uniformity of silver nanofilm is improved by MPTMS treatment for various transparent substrates, resulting in a 100-fold decrease in the electrical resistance of the silver nanofilm.

• Convergence Security Journal
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• v.23 no.5
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• pp.135-142
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• 2023

In addressing the prominent issues of climate change, resource scarcity, and environmental pollution associated with household waste, extensive research has been conducted on intelligent waste classification methods. These efforts range from traditional classification algorithms to machine learning and neural networks. However, challenges persist in effectively classifying waste in diverse environments and conditions due to insufficient datasets, increased complexity in neural network architectures, and performance limitations for real-world applications. Therefore, this paper proposes i-YOLOX as a solution for rapid classification and improved accuracy. The proposed model is evaluated based on network parameters, detection speed, and accuracy. To achieve this, a dataset comprising 10,000 samples of household waste, spanning 17 waste categories, is created. The i-YOLOX architecture is constructed by introducing the Involution channel convolution operator and the Convolution Branch Attention Module (CBAM) into the YOLOX structure. A comparative analysis is conducted with the performance of the existing YOLO architecture. Experimental results demonstrate that i-YOLOX enhances the detection speed and accuracy of waste objects in complex scenes compared to conventional neural networks. This confirms the effectiveness of the proposed i-YOLOX architecture in the detection and classification of multiple household waste objects.

• Journal of Korea Society of Industrial Information Systems
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• v.29 no.2
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• pp.101-117
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• 2024

The purpose of this study is to consider the characteristics perceived by users who utilize MyData services in the financial sector. It aims to examine how these factors influence users' understanding for sustained usage and their resistance to innovation. The research seeks to explore the relationship between users' awareness of characteristics and its impact on both enhancing comprehension for continued usage and addressing users' resistance to innovation. Utilizing a specialized survey agency, we examined the relative effects of innovation resistance factors, such as relative advantage, perceived risks, complexity, clarity and perceived ease of use on MyData service users. Furthermore, this research focuses on employing empirical analysis to validate the relationships between these factors through the survey. The findings of this study suggest that MyData service should dedicate ongoing efforts to minimize user resistance to service utilization. Specifically, it was revealed that among the innovation resistance factors, perceived ease of use, relative advantage, perceived risk, and complexity exert influence in that order.