• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.228-229
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• 2012

3상 전압형 인버터는 직류전압을 전원으로 하여 3상 교류로 내보내는 대표적인 전력변환시스템이다. 3상 전압형 인버터의 효율을 극대화 시키는 연구가 활발히 진행되고 있는 현재 시점에 스위칭횟수는 전체 시스템 효율향상에 큰 영향을 미친다. 본 논문에서는 3상 전압형 인버터의 기존 스위칭시퀀스를 탈피하여 간략화 스위칭시퀀스 전략을 도입하여 스위칭손실을 저감시킬 수 있는 3상 전압형 인버터의 SVPWM 제어기법을 제안하고, 유효성을 시뮬레이션 및 실험을 통해서 검증한다.

• Proceedings of the KIPE Conference
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• 2016.11a
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• pp.161-162
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• 2016

본 논문에서는 권선 사이의 자계결합도 변동을 고려하여 자기공진 방식의 보조권선을 포함하는 전기차 충전용 무선전력전송회로의 설계기법을 제시한다. 전기차 충전용 무선전력전송회로를 설계하기 위해서는 회로의 동작주파수가 표준규격에 의해서 일정범위로 제한되고 1차측과 2차측 권선의 정렬상태에 따라서 자계결합도가 변동할 수 있다는 점이 고려되어야 한다. 본 논문에서는 동작주파수의 제한범위 및 자계결합도의 변동을 고려하여 1차측에 보조권선을 포함하는 자기공진형 무선전력전송회로의 설계기법을 제시한다.

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.195-196
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• 2015

본 논문에서는 전기자동차 긴급구난용 급속충전 병렬능동클램프 고효율 절연형 DC/DC 컨버터를 제안한다. ZVS 턴온동작하여 스위칭손실을 저감하고, 능동클램프 스위칭소자에 대한 스위칭주파수와 전류를 저감시킬 수 있도록 토폴로지의 개선과 함께 제어기법을 도입한 20kW급 전기자동차 급속충전 전력변환시스템을 제안하고, 이에 대한 유효성을 시뮬레이션 및 실험을 통해 검증한다.

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.163-164
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• 2015

본 논문에서는 자기유도 방식의 3.3kW급 무선전력전송회로의 설계 및 실험결과를 제시한다. 본 논문에서 고려하는 무선전력전송회로는 전기차 무선충전에 적용하는 것을 염두에 두고 이격거리는 17.5cm를 기준으로 하는 한편, 최근 전기차 무선충전 분야의 표준화 동향을 고려하여 동작주파수 범위는 85kHz 내외로 유지하는 것을 설계사양으로 채택하였다. 또한, 전기차무선충전에 있어서 급전단과 수전단의 이격거리, 정렬오차 등의 변동으로 인한 자기 결합도의 변동이 있을 수 있음을 감안하여 이를 설계에 반영하였다. 설계사양을 검증하기 위해 실험용 회로를 구성하였고 이에 대한 효율시험 결과를 제시하였다.

• Journal of IKEEE
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• v.23 no.1
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• pp.346-349
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• 2019

Product liability is an important regulation factor in automotive industry. ISO 26262 international standard was established as an exemption clause of product liability. In autonomous car, product liability becomes more important, and ISO/PAS international standard was additionally established, but it can be applied to only sensing stage, which can partly make the autonomous car companies exempt the product liability but not completely. Therefore, reform of current legal system is absolutely necessary to commercialize autonomous car until a new international standard is established as a complete exemptions clause.

• Structural Engineering and Mechanics
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• v.85 no.6
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• pp.743-753
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• 2023

Piezoelectricity is defined as the ability of certain materials to produce electric signals when mechanically stressed or to deform when an electrical potential is applied. Piezo technology is becoming increasingly crucial as intelligent devices use vibration sensors to detect vibrations in consumer electronics, the automotive industry, architectural design, and other applications. A wide range of applications is now possible with piezoelectric sensors, such as skin-attachable devices that monitor health and detect diseases. In this article, copper nanoparticles are used in the piezoelectric sensor as the driving agent of the magnetic field. Magnetic nanocatalysts containing copper nanoparticles are used due to their cheapness and availability. Considering that the increase of the electric field acting on the piezoelectric increases the damping (As a result, damping materials reduce radiation noise and increase material transfer losses by altering the natural vibration frequency of the vibrating surface). Among the advantages of this method are depreciating a significant amount of input energy using high energy absorption capacity and controlling slight vibrations in the sensors.

• International Journal of Korean Welding Society
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• v.3 no.2
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• pp.53-59
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• 2003

Visual inspection using laser vision sensor was proposed for fast and economic inspection and was verified experimentally. Welding is one of the most important manufacturing processes for automotive and electronics industries as well as heavy industries. The weld zone influences the reliability of the products. There are two kinds of weld inspection tests, destructive and non­destructive test. Even though the destructive test is much more reliable, the product should be destroyed, and hence the non­destructive test such as ultrasonic or X­ray test was used to overcome this problem. However, these tests are not used for real time inspection.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.695-697
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• 2011

AUTOSAR 는 차량용 시스템의 소프트웨어 인프라를 표준화하여 차량용 소프트웨어의 재사용성을 높이고자 개발된 차량용 소프트웨어 구조 표준안이다. 그러나, 기존 AUTOSAR 는 새로운 하드웨어의 추가 및 변경을 지원할 수 없기 때문에 하드웨어의 변경에 대해 유연하게 적응할 수 있는 구조 또는 기법이 필요하다. 따라서, 본 논문에서는 AUTOSAR 의 모델에 Workflow 를 도입하고, 동적인 네트워크를 구축하여 Plug & Play 기능을 지원하는 차량용 소프트웨어 구조를 제안한다.

• Journal of the Economic Geographical Society of Korea
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• v.27 no.3
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• pp.174-191
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• 2024

This study analyzed the spatiotemporal evolution of Korean multinational corporations' (MNCs') foreign direct investment (FDI) networks from 1978 to 2023, focusing on Samsung Electronics and LG Electronics. Using data on the consolidated overseas subsidiaries of these two companies, a two-mode network was constructed to examine the status of host countries through the betweenness centrality index and to identify types of countries with similar value chain arrangements by investigating their linkage structures. The main findings are as follows. First, during the early phase of Korean electronics MNCs' overseas expansion in the 1980s, they primarily established sales bases in developed consumer markets. However, over time, they gradually expanded into other business areas, including manufacturing, producer services, and R&D, increasing complexity in their FDI networks as cross-border mergers and acquisitions (M&As) became more frequent. Second, the United States has remained central to these MNCs' FDI networks since the 1980s, but more recently, China has emerged as a significant hub, challenging the U.S. in global value chains. Third, emerging Asian economies, including India, Vietnam, and Indonesia, have strengthened their positions due to the diversification of MNCs' investment objectives from manufacturing bases to a broader range of business areas. Finally, since the 2010s, the convergence of the electronics industry with the automotive electronics sector and new industries has led to a diversification of the value chain arrangements of Korean electronics MNCs.

• Journal of IKEEE
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• v.20 no.2
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• pp.205-208
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• 2016

In this paper, different types of touch screen silver pastes for bonding in conductive pattern formed over the ito film by bonding each sample of 5 was dried. The dry conditions, the oxidation of the ito film is a condition that does not occur. Reliability testing constant temp and humidity, cold-hot impact test is in progress. Each test will check the status of five sheets conductive pattern bonding. Conductive pattern bonding, after each 240,480,615 hours to check the status of silver pattern bonding. Reliability testing these through different silver pastes can see that the change in the adhesion and conductivity deterioration of the quality can be prevented, and reliability testing low temperature curing from the surface of silver pastes that can come as soon as the discoloration was unknown.