• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.4679-4684
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• 2013

Compared with internal combustion engine, the electric vehicle has a limitation of low driving range due to low battery capacity due to relatively low energy density. Moreover, the energy consumption rapidly increases up to 30% during winter season with operating electric heater. In this study, electric vehicle performance was evaluated using heat pump having higher energy efficiency rather than electric heater for cabin heating. Electric vehicle system and heat pump system were developed using 1-D simulation software called AMESim, the simulation result indicated that the energy consumption could be reduced approximately 66% when the electric heating system was replaced with the heat pump system. As a result, the driving range is expected to increase the similar value. This study proved the merit of heat pump for cabin heating in electric vehicle, and it could contribute to developing suitable heating method for electric vehicles.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.247-252
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• 2012

Of late, the development of advanced batteries with high power density and capacity has been indispensible for pushing ahead with much wider applications to electric vehicles and smart IT devices. However, a conventional Li-ion battery contains a limited energy density due to various technological challenges such that other types of Li batteries including Li-S and Li-air have been extensively studied due to their interestingly high energy capacities. Sulfur and oxygen, of which both are cathode materials, showing similar physicochemical characteristics have widely been available which may also contribute to the commercialization of these batteries. In this review, we introduce some perspectives in improving these advanced Li batteries through several approaches such as the provision of porous cathode structures, the optimization of cathode-electrolyte interfaces and the modification of Li anodes.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.83-88
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• 2018

The electromigration (EM) tests were performed at $150^{\circ}C$ with $1.5{\times}10^5A/cm^2$ conditions in order to investigate the effect of non-conductive film (NCF) trap on the electrical reliability of Cu/Ni/Sn-Ag microbumps. The EM failure time of Cu/Ni/Sn-Ag microbump with NCF trap was around 8 times shorter than Cu/Ni/Sn-Ag microbump without NCF trap. From systematic analysis on the electrical resistance and failed interfaces, the trapped NCF-induced voids at the Sn-Ag/Ni-Sn intermetallic compound interface lead to faster EM void growth and earlier open failure.

• Journal of IKEEE
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• v.26 no.4
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• pp.686-692
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• 2022

In this paper, the matching error rates of modified area-based, energy-based algorithms, and learning-based structures were compared for stereo image matching. Census transform (CT) based on region and life propagation (BP) algorithm based on energy were selected, respectively.Existing algorithms have been improved and implemented in an embedded processor environment so that they can be used for stereo image matching in mobile systems. Even in the case of the learning base to be compared, a neural network structure that utilizes small-scale parameters was adopted. To compare the error rates of the three matching methods, Middlebury's Tsukuba was selected as a test image and subdivided into non-occlusion, discontinuous, and disparity error rates for accurate comparison. As a result of the experiment, the error rate of modified CT matching improved by about 11% when compared with the existing algorithm. BP matching was about 87% better than conventional CT in the error rate. Compared to the learning base using neural networks, BP matching was about 31% superior.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.01a
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• pp.35-38
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• 2023

포트홀은 주행하는 자동차와 접촉이 이뤄지면 차체나 운전자에게 충격을 주고 제어를 잃게 하여 도로 위 안전을 위협할 수 있다. 포트홀의 검출을 위한 국내 동향으로는 진동을 이용한 방식과 신고시스템 이용한 방식과 영상 인식을 기반한 방식이 있다. 이 중 영상 인식 기반 방식은 보급이 쉽고 비용이 저렴하나, 컴퓨터 비전 알고리즘은 영상의 품질에 따라 정확도가 달라지는 문제가 있었다. 이를 보완하기 위해 영상 인식 기반의 딥러닝 모델을 사용한다. 따라서, 본 논문에서는 사전 학습된 딥러닝 모델의 정확도 향상을 위한 Feature Level Ensemble 기법을 제안한다. 제안된 기법은 사전 학습된 CNN 모델 중 Test 데이터의 정확도 기준 Top-3 모델을 선정하여 각 딥러닝 모델의 Feature Map을 Concatenate하고 이를 Fully-Connected(FC) Layer로 입력하여 구현한다. Feature Level Ensemble 기법이 적용된 딥러닝 모델은 평균 대비 3.76%의 정확도 향상을 보였으며, Top-1 모델인 ShuffleNet보다 0.94%의 정확도 향상을 보였다. 결론적으로 본 논문에서 제안된 기법은 사전 학습된 모델들을 이용하여 각 모델의 다양한 특징을 통해 기존 모델 대비 정확도의 향상을 이룰 수 있었다.

• Korean Journal of Construction Engineering and Management
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• v.25 no.2
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• pp.36-44
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• 2024

This paper presents the application of Convolutional Neural Networks (CNNs) and Region of Interest (ROI) techniques for concrete crack analysis. Surfaces of concrete structures, such as beams, etc., are exposed to fatigue stress and cyclic loads, typically resulting in the initiation of cracks at a microscopic level on the structure's surface. Early detection enables preventative measures to mitigate potential damage and failures. Conventional manual inspections often yield subpar results, especially for large-scale infrastructure where access is challenging and detecting cracks can be difficult. This paper presents data collection, edge segmentation and ROI techniques application, and analysis of concrete cracks using Convolutional Neural Networks. This paper aims to achieve the following objectives: Firstly, achieving improved accuracy in crack detection using image-based technology compared to traditional manual inspection methods. Secondly, developing an algorithm that utilizes enhanced Sobel edge segmentation and ROI techniques. The algorithm provides automated crack detection capabilities for non-destructive testing.

• Information and Communications Magazine
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• v.26 no.1
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• pp.25-30
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• 2009

IT산업은 '97년 외환위기를 기점으로 고성장을 거듭하였고, 세계 10위권 규모의 경제 강국으로 성장하는데 있어 국내 산업의 대표적인 성장동력으로서 자리 매김하였다. 하지만, 최근 성장률이 예전만 못하다는 우려의 목소리와 함께 IT가 한 단계 더 업그레이드하기 위해서는 자신의 허물을 과감히 벗는 용기가 필요하다는 것이 일반적인 시각이다. 이러한 흐름속에서 기존 IT전략과 차별화된 New IT 발전방안을 수립하게 되었다. 지금까지의 IT전략이 IT 고도화 추진을 위한 IT 중심 발전 전략이었다면, New IT전략은 IT기반 융합산업, IT융합 신산업, Next IT산업 등3대 성장축간 시너지 창출이 가능한 IT로의 수렴과 확산이 핵심이라고 할 수 있다. IT기반 융합산업의 최종 목표는 전통산업과 IT가 만나 자동차, 조선, 의료, 국방, 건설, 섬유, 기계항공 등 7개 주력기간산업의 고부가가치화 및 초일류화를 우선 실현하는 것이다. IT융합 신산업의 최종 목표는 나노(NT), 바이오(BT), 인지기술(CT) 등 비(非)IT와 교감을 통하여 IT가 에너지, 환경, 건강 등 사회적 문제를 해결하고, 녹색성장 추진의 핵심인 5대 신산업을 창출하는데 있다. 5대 신산업으로는 Green IT산업, Welfare-Infra산업, 감성조명산업, 인지단말산업, THz응용산업 등을 꼽을 수 있다. Next IT산업은 기존 14대 IT 분야를 'ETRI 비전 2020' 등 미래 청사진을 바탕으로 장기적 관점에서 재설계한 것이며, 최종 목표는 TDX, 4M D램, CDMA, 와이브로, DMB, NoLA 등 IT 강국 계보를 이어갈 4G, 미래인터넷, Smart Radio, 실감미디어, 웹3.0, 투명전자소자 등 미래 유망 핵심원천기술을 확보하고, IT 경쟁력을 강화하는 것이다.

• Journal of Environmental Policy
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• v.6 no.4
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• pp.29-54
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• 2007

Compared to corporate social responsibility(CSR) as business practices, government CSR policy have not been given much attention by researchers. This paper suggests drivers of government CSR policies and a conceptual model through examining concepts and social needs of CSR. The conceptual model encompasses three government roles: CSR vision setting, promoting and partnering. CSR can be useful to facilitate international transfer of clean technology, globalization of resource development companies, support for energy consumption of low-income classes. This paper concludes with summary and directions for future research focusing on areas of environmental and energy policies.

• Transactions of the KSME C: Technology and Education
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• v.5 no.1
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• pp.69-77
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• 2017

Nanotechnology, along with Information Technology (IT) and Bio-technology (BT), has been regarded as a core area that will drive technological revolution of $21^{st}$ century. South Korea and other countries with advanced scientific and technological research programs are investing heavily in the field, and among its various aspects, nanomaterial industry is considered to be at the heart of this global competition. In this review, we look at nanomaterials industry from the perspective of mechanical engineering. Nanomaterials exhibit unique characteristics differing from those of micron, or sub-micron sized materials, and hence are potentially able to open up new opportunities. Specifically, environmental and biological sciences, energy, and catalysis are areas that are expected to benefit from these developments.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.449-450
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• 2007

오래 전 부터 영상처리와 컴퓨터 비전은 많은 분야에 응용되고 발전 되어 왔다. 그러한 기술 중에 최근 각광 받고 있는 그래프 짓(Graph cut) 알고리즘은 에너지함수를 최소화 하는 가장 강력한 최적화 기법중 하나이다. 그리고 일반적으로 Sobel, Prewitt, Roberts, Canny 에지(edge) 검출기 등은 영상처리에서 영상상의 에지를 검출하기 위해 이미 널리 사용되고 발전되어 온 기술이다. 물체에서의 윤곽만 검출하기 위해서는 우리가 원하지 않는 영상 위의 에지도 검출되기 때문에 예지 검출기만으로는 물체의 윤곽만을 검출하는 것은 불가능하다. 우리는 물체의 윤곽만 검출하기를 원하기 때문에 그래프 컷과 에지 검출기의 알고리즘을 결합하면 이러한 문제를 해결 할 수 있다는 것을 제안한다. 이 논문에서는 그래프 컷 알고리즘과 에지 검출기에 관해 간략하게 기술하고 그 결과를 보일 것이다.