• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.5
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• pp.197-217
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• 2022

As automated vehicle(AV) accidents continue to occur, the importance of safety verification to ensure the safety and reliability of automated driving system(ADS) is being emphasized. In order to encure safety and reliability, it is necessary to define an operational design domain(ODD) of the ADS and verify the safety of the ADS while evaluating its ability to respond in situations outside of the ODD. To this, international associations such as SAE, BSI, NHTSA, ISO, etc. stipulate ODD standards. However, in Korea, there is no standard for the ODD, so automated vehicles's ODD expression method and safety verification and evaluation are not properly conducted. Therefore, this study analyzed overseas ODD standards and selected suitable ODD for safety verification and evaluation, and presented evaluation elements for ADS safety verification and evaluation. In particular, evaluation elements were selected by analyzing the evaluation environment of the automated driving experimental city (K-City) that supports the development of ADS technology.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.3
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• pp.240-248
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• 2013

Torsional vibrations, such as the gear rattle of the manual transmission in vehicle systems, are correlated with the firing stroke from the engine. These vibro-impacts can be examined based upon linear time-invariant analysis. In order to understand the gear dynamics, a specific manual transmission with a front-engine front-wheel drive configuration is investigated. A method to reduce the degrees of freedom is suggested based upon the eigensolutions and frequency response functions, which will lead to the development of an efficient matrix size. The dynamic characteristics of single- and dual-mass flywheels are then compared. The effect of the dual-mass flywheel is investigated based upon the mobility analysis, which will lead to understanding of the concepts for avoiding vibro-impacts. A linear time-invariant system model is examined by employing the effective clutch stiffness from a two-stage clutch damper. Thus, the relationship between the dynamic characteristics and the clutch damper can be predicted by assuming a combination of different stage stiffness levels.

• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.34-50
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• 2022

Since the Paris climate agreement, reducing greenhouse gases has been the most important global issue. In particular, it is necessary to reduce fossil fuels in the mobility sector, which accounts for a significant portion of total greenhouse gas emissions. In this paper, we investigated the economic feasibility of green mobility energy supply chains, which supply hydrogen as fuel to hydrogen vehicles based on electricity from renewable energy sources. The design and operation costs were analyzed by evaluating nine scenarios representing various combinatorial possibilities such as renewable energy generation, hydrogen production through water electrolytes, hydrogen storage and hydrogen refueling stations. Simulation calculations were made using Homer Pro, widely used commercial software in the field. The experience gained in this study could be further utilized to construct actual hydrogen energy systems.

• Journal of the Korea Society of Computer and Information
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• v.28 no.3
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• pp.35-43
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• 2023

Emotion recognition while driving is an essential task to prevent accidents. Furthermore, in the era of autonomous driving, automobiles are the subject of mobility, requiring more emotional communication with drivers, and the emotion recognition market is gradually spreading. Accordingly, in this research plan, the driver's emotions are classified into seven categories using psychological and behavioral data, which are relatively easy to collect. The latent vectors extracted through the auto-encoder model were also used as features in this classification model, confirming that this affected performance improvement. Furthermore, it also confirmed that the performance was improved when using the framework presented in this paper compared to when the existing EEG data were included. Finally, 81% of the driver's emotion classification accuracy and 80% of F1-Score were achieved only through psychological, personal information, and behavioral data.

• Composites Research
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• v.35 no.6
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• pp.365-370
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• 2022

According to the rapid growth of electric vehicle (EVs) and E-mobility market, Li-ion batteries are one of the most progressive technologies. The demand of LIBs with high energy capacity, rate performance and fast charging is continuously increasing, hence high-performance LIBs should be developed. Si is considered as the most promising anode material to improve energy density because of its high theoretical capacity. However, Si suffers large volume chances during the charging and discharge process, leading to the fast degradation of cycle performance. Therefore, polymeric binders play a key role in electrochemical performance of Si anode by efficiently enduring the Si expansion and maintaining the binding networks in electrode. In this review, we explain the role of polymeric binders in electrode and introduce the anode binders with enhanced mechanical and chemical properties which can improve electrochemical performances of Si-based anode.

• Annual Conference of KIPS
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• 2023.11a
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• pp.281-282
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• 2023

자율주행 자동차 시장 규모 및 기술이 급속도로 성장하고 있음에도 불구하고, 전문가 교육을 위한 높은 하드웨어 비용 때문에 실제로 이 기술을 실험하기 위한 집단 교육 플랫폼의 필요성이 높아졌다. 이에 따라 우리는 자율주행에 사용되는 센서와 액츄에이터, 그리고 자율주행 알고리즘 학습을 위한 1/5 크기의 하드웨어를 포함한 교육 플랫폼을 설계했다. 이 교육 프로그램은 온라인 강의와 실습으로 구성되며, 각각의 모듈은 로봇 운영체제(ROS)를 활용한 C언어로 개발되었다. 이 교육 플랫폼은 언제 어디서나 접근 가능한 온라인 형식으로 제공되므로, 학생들은 이론과 실습을 통해 자율주행 분야의 전문가로 성장할 수 있는 기회를 얻게 되고 혁신과 경쟁력 강화에 기여할 것으로 기대된다.

• Asia-Pacific Journal of Business
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• v.14 no.3
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• pp.149-166
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• 2023

Purpose - This study aimed to examine the influence of various factors on customer satisfaction and the continuance usage intention, based on the purchasing type of smart speaker users. Design/methodology/approach - Data was gathered through surveys, collecting responses from 180 smart speaker users in Korea. Structural equation modeling was utilized to analyze the data. Findings - Both perceived usefulness and perceived security were observed to have a significant positive impact on customer satisfaction across all user groups. Moreover, perceived ease of use and perceived versatility showed a significant positive effect on the continuance usage intention. Notably, for those who acquired the smart speakers for free, perceived usefulness had a positive impact on the continuance usage intention. Conversely, for those who made a paid purchase, perceived versatility played a significant role in driving customer satisfaction. Research implications or Originality - This research offers insights into the Korean smart speaker market, a unique environment where local competitors thrive in the absence of giants like Amazon and Google. It provides a nuanced view of customer reactions to these innovative devices. The study further distinguishes between high-involvement (paid purchase users) and low-involvement (free acquisition users) consumers, offering a more detailed understanding of user perspectives based on their acquisition mode.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.1
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• pp.291-310
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• 2023

This study explores the factors which affect user acceptance for Robo Taxi, an electricity-based Autonomous Vehicles based on a Value based Adoption Model. The three main factors of benefit (usefulness and enjoyment), sacrifice (technicality and perceived fee level), and user experience about mobility services such as car sharing, taxi, and autonomous vehicles, were finally selected as independent variables as a influential factors on perceived values and adoption intention of Robo taxi. The study found that usefulness, enjoyment, and perceived fee had a significant effects on adoption intention, and some user experiences had a significant effect on benefit factors. This study has important implications for incorporating the Value-based Adoption Model results into the service design for the activation of Robo taxi, and furthermore, they can provide a theoretical basis for effective use of the research findings.

• Clean Technology
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• v.30 no.3
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• pp.159-174
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• 2024

The rapid increase in energy consumption based on fossil fuels is accelerating global warming. In particular, the road transportation sector has high carbon dioxide emissions, so transitioning towards electric vehicles is recommended. Thus, the importance of secondary batteries is increasing. Secondary batteries are reversible batteries that use energy and can be reused through a charging and discharging process. Currently, lithium-ion batteries are widely used. Secondary batteries place importance on six major factors: energy, output, lifespan, environmental friendliness, cost, and stability. Research is actively being conducted to satisfy all six factors by understanding the material characteristics of each component of the battery. As it is difficult to move away from lithium as a cathode material, researchers are investigating higher performance materials that mix materials such as cobalt, nickel, manganese, and aluminum with lithium and use graphite, silicon, and lithium metal to increase capacity. In the case of electrolytes, liquid electrolytes are still mainly used. However, solid electrolytes are being studied due to their stability, but additional research must be conducted to satisfy the energy and output factors. This review paper aims to provide an understanding of secondary batteries through an overview of secondary batteries, the materials and characteristics of their components, their technological trends, and their associated companies.

• Journal of the Korean Institute of Gas
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• v.25 no.6
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• pp.85-91
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• 2021

In January 2019, the Korean government announced the 「Hydrogen Economy Activation Roadmap」 to be a world-class leading country in Hydrogen economy. Korea has established a strategy that can lead the hydrogen economy with its strong points of 'hydrogen car' and 'fuel cell'. As a part of that, a target of supplying hydrogen vehicle charging stations to 310 by 2022 and 1,200 by 2040 was established. In line with this, Korea Gas Safety Corporation will operate a pre-consulting system of hydrogen vehicle charging station in February 2021 to solve in advance construction delays due to various on-site problems according to safety standards during the construction stage to build a hydrogen refueling station with a sense of speed. This paper is to find out about the pre-consulting system and to analyze its effects.