• 한국위성정보통신학회논문지
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• 제8권4호
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• pp.95-99
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• 2013

GPS는 차량용 네비게이션, 스마트폰 등의 일상생활에서 사용될 뿐만 아니라. 이동통신망, 전력망, 금융망 등 국가 기간통신망에 활용되는 중요한 인프라이다. 하지만 GPS는 신호세기가 미약하여 전파 교란에 매우 취약한 단점이 있다. GPS 교란은 사회적으로 혼란을 초래하는 심각한 문제이므로, 이를 예방 및 최소화하기 위하여 국가차원에서 GPS 전파교란 감시 기술 개발이 되어 운용되고 있다. 본 논문은 GPS L1/L2 대역의 교란신호를 검출하고, 교란신호의 방향 및 위치를 파악하는 기능을 제공하는 GPS 교란 감시장치의 구현 및 시험 결과를 제시한다. GPS 교란 감시 장치의 주요 기능, 형상 및 구성에 대해 설명하고, 동작 시나리오, S/W 및 H/W 구현 결과를 보여준다. 또한, GPS 교란신호를 발생시켜 검출, 방향파악 및 위치파악 시험을 수행하였고, 그 결과를 통해 GPS 교란 감시 장치가 정상적으로 동작됨을 보여준다.

• 한국자동차공학회논문집
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• 제10권2호
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• pp.166-173
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• 2002

The wheel bearing hub unit is developed type of wheel bearing unified with the hub parts. It has advantage of reducing the weight and the number of components. And, it also improves uniformity of manufacturing quality, In order to design the wheel bearing hub units, many techniques are used such as load analysis, structure analysis and bearing characteristics analysis and so forth. These techniques need highly accurate load conditions founded on service conditions. In this study, to design the wheel bearing hub units used widespread in passenger cars, the service load was measured through driving tests on the public roads and in the special events. The public roads are classified into highway, intercity road, rural road, urban road, and unpaved road so as to know what the characteristics of the road loads are. The results of the tests showed that the wheel force was relative to the lateral acceleration, and also could be calculated from the lateral acceleration. The lateral acceleration was measured from 0.0G to 0.6G in general driving on the public roads, with different distributions in each road type. In special events, the maximum lateral acceleration was measured from 0.8G to 1.3G.

• Archives of Reconstructive Microsurgery
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• 제25권2호
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• pp.69-71
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• 2016

Reconstruction of the lower extremities is difficult due to a lack of skin laxity and muscular tissues. Here, we present a case of lower extremity reconstruction via the anterior tibial artery perforator based segmental muscle island flap. Our patient was a 75-year-old male with a chronic ulcerative wound on the right lower leg from an old car accident. A $5.0{\times}0.5cm$ size ulcerative wound with tibial bone exposure was noted. We planned to reconstruct the lower extremity defect with a free flap, but the vessel status was severely compromised intraoperatively. Thus, we found the anterior tibial artery perforator using Doppler ultrasound, elevated the tibialis anterior muscle segment flap, and transposed it to cover the defect successfully. The flap presented with a nice contour and the skin graft covering the flap survived completely. There were no complications of the surgical site at three months follow-up and no gait morbidity. This is a meaningful case applying the concept of segmental muscle flap based on a perforator that had advantages including proper bulkiness, vascularization, and preservation of function, which were well applied, leading to great success.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.548-551
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• 2018

대다수 차량은 문제가 발생하면 사용자가 직접 정비소에 방문하여 정비가 이뤄지는 형태를 취하고 있다. 정비가 이뤄지는 동안 사용자는 운행을 하지 못하는 불편함과 함께, 대상 차량이 수익을 창출하는 차량이라면 경제적인 손실도 감수해야 한다. 실시간으로 차량 정보를 수집하고, 수집된 빅데이터를 기반으로 차량에서 발생할 수 있는 문제를 파악하여 사후 서비스 보다는 사전 서비스를 제공한다면, 안정된 차량 운행에 도움을 줄 수 있으며, 경제적 손실도 감소할 수 있다. 이에 본 논문에서는 IoT기반 게이트웨이를 설계하고, 실시간 차량 정보를 수집하여 빅데이터를 구성하여 실시간으로 차량 정보를 제공할 수 있는 플랫폼을 설계하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.493-499
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• 2003

Railroad, a superior mode of public transportation provides safe, efficient, speedy, comfortable and economical service, has fundamentally different characteristics from airplanes, ships and cars. Among the unique characteristics of a railroad is the fact that it operates on fixed track with multiple car trains. The subway system was first selected as the best solution to difficult automobile traffic conditions and environmental problems. Seoul subway no.1line (Jongno line) was opened for service on August 15, 1974. Seoul city has completed and now operates eight subway lines (286.7km) since 1974. At present the subways operate in Busan, Daegu and Incheon city, and are under construction in Gwangju and Daejeon city. The power source for subway trains has been electricity since 1896, and power supply systems are the third rail type and/or the catenary system. The typical catenary system is the rigid bar type. R-bar and T-bar are used in the rigid bar type of catenary system, and the two types of R-bar and T-bar are uesd in Korea also. R-bar is used only for AC 25kV power supply and T-bar for DC 1,500V. From 30 years of subway experience I would like to suggest the most economic catenary system to ensure of safety, reliability and expediency for the railway lines to be constructed and the forthcoming replacement due to the life cycle after studying and analysing the characteristics, advantages and disadvantages of R-bar and T-bar.

• 한국철도학회논문집
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• 제11권4호
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• pp.410-416
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• 2008

본 연구에서는 '2003년 산업연관표'를 사용하여 우리나라의 철도운송산업이 국내 운송산업 전체에서 차지하는 위상 및 철도운송산업과 여타산업의 관계적 특징에 대하여 살펴보았다. 그리고 산업연관분석 연구방법을 사용하여 국내 철도운송산업의 생산활동이 403개 여타 기본산업에 미치는 경제적 파급효과에 대해서 분석하였다.

• 한국위성정보통신학회논문지
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• 제8권2호
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• pp.62-67
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• 2013

최근 위성항법장치를 활용한 GPS(Global Positioning System)를 통해 위성에서 보내는 위치정보를 이용하여 사용자에게 다양한 서비스를 제공하는 위치기반서비스가 이뤄지고 있다. 하지만 위성신호의 특성상 고층 건물이 밀집되어 있는 도심과 같은 지역에서는 반사, 굴절로 인해 오차를 가진 위치정보를 얻게 된다. 본 연구과제는 GPS 위치신호 오차를 보정하기 위해 사용자의 이동방향 정보의 방향벡터를 계산하여 분산된 위치좌표를 방향벡터 위로 보정하는 후처리 알고리즘을 제안하고자 한다. 도심지역에서의 차량주행 실험을 통하여 기존 GPS 보다 평균 11.1m(43%)의 정확도 향상을 통하여 제안한 후처리 알고리즘의 우수성을 입증하였다.

• 한국항공운항학회지
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• 제28권4호
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• pp.132-140
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• 2020

The development status was studied to predict the concept of how drone taxis would be presented in daily life. the results of the analysis on traffic effects of drone taxis showed that they would be an innovative transportation option that could reach a distance of 60km, which would typically take an hour by car, within twenty minutes. Moreover, the economic analysis of existing aircraft development was limited to production (development investment) of the input budget. However, since the drone taxi is a new transportation system, an overall traffic platform, such as its own terminals, would need to be established. So, the production inducement effect was analyzed by dividing input budget into three factors; production, infrastructure, and service. The results indicate this to be an innovative project expected to have an economic ripple effect and reach a total of 24 trillion won after an investment of 13 trillion won (production + infrastructure + service) in Korea from 2020 to 2040.

• Journal of Multimedia Information System
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• 제9권1호
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• pp.11-20
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• 2022

In this paper, we have recently created self-driving cars and self-parking systems in human-friendly cars that can provide high safety and high convenience functions by recognizing the internal and external situations of automobiles in real time by incorporating next-generation electronics, information communication, and function control technologies. And with the development of connected cars, the ITS (Intelligent Transportation Systems) market is expected to grow rapidly. Intelligent Transportation System (ITS) is an intelligent transportation system that incorporates technologies such as electronics, information, communication, and control into the transportation system, and aims to implement a next-generation transportation system suitable for the information society. By combining the technologies of connected cars and Internet of Things with software features and operating systems, future cars will serve as a service platform to connect the surrounding infrastructure on their own. This study creates a research methodology based on the Enhanced Security Model in Self-Driving Cars model. As for the types of attacks, Availability Attack, Man in the Middle Attack, Imperial Password Use, and Use Inclusive Access Control attack defense methodology are used. Along with the commercialization of 5G, various service models using advanced technologies such as autonomous vehicles, traffic information sharing systems using IoT, and AI-based mobility services are also appearing, and the growth of smart transportation is accelerating. Therefore, research was conducted to defend against hacking based on vulnerabilities of smart cars based on artificial intelligence blockchain.

• Journal of Multimedia Information System
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• 제9권1호
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• pp.33-42
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• 2022

In this paper, we have recently created self-driving cars and self-parking systems in human-friendly cars that can provide high safety and high convenience functions by recognizing the internal and external situations of automobiles in real time by incorporating next-generation electronics, information communication, and function control technologies. And with the development of connected cars, the ITS (Intelligent Transportation Systems) market is expected to grow rapidly. Intelligent Transportation System (ITS) is an intelligent transportation system that incorporates technologies such as electronics, information, communication, and control into the transportation system, and aims to implement a next-generation transportation system suitable for the information society. By combining the technologies of connected cars and Internet of Things with software features and operating systems, future cars will serve as a service platform to connect the surrounding infrastructure on their own. This study creates a research methodology based on the Enhanced Security Model in Self-Driving Cars model. As for the types of attacks, Availability Attack, Man in the Middle Attack, Imperial Password Use, and Use Inclusive Access Control attack defense methodology are used. Along with the commercialization of 5G, various service models using advanced technologies such as autonomous vehicles, traffic information sharing systems using IoT, and AI-based mobility services are also appearing, and the growth of smart transportation is accelerating. Therefore, research was conducted to defend against hacking based on vulnerabilities of smart cars based on artificial intelligence blockchain.