Plasmonic Structural-Color Thin Film With a Wide Reception Angle and Strong Retro-Reflectivity

Inchul Woo,Sunkyu Yu,Jae Sung Lee,Shin, J. H.,Mi Jung,Namkyoo Park IEEE 2012 IEEE photonics journal Vol.4 No.6

<P>We propose a plasmonic structural color in the form of a thin film with a monolayer of randomly dispersed silver nanoshells. By employing spatially isotropic optical dipole antenna nanoshells to achieve efficient couplings to obliquely incident field and by utilizing local frustration and interference of randomly dispersed scatterer phases, we successfully introduce plasmonic-driven unique traits of retro-reflection as an example of a plasmonic structural color. As compared to the natural counterpart, Morpho rhetenor , a much wider reception angle, up to 70<SUP>°</SUP>, and a stronger retro-reflectivity of 35-45% are achieved.</P>

A study on lane path contents for car navigation systems to resolve road inconvenience

Inchul Yang(양인철),Woo Hoon Jeon(전우훈) 한국디지털콘텐츠학회 2019 한국디지털콘텐츠학회논문지 Vol.20 No.1

As shown in many recent studies, the different traffic flow characteristics between lanes are very important in terms of generating and managing traffic information. If avoiding congested road sections is an important purpose of navigation systems, avoiding congested lanes by using traffic state information by lane will also be an important function of navigation systems for resolving road inconvenience in the future. Therefore, this paper proposes a lane-path calculation method required for lane-path services which will be a core content of navigation systems in the future. For this purpose, we proposed a lane-path calculation method for uninterrupted roads by observing the traffic state by each lane. This study collected the travel time by each lane on the Gangbyeon Expressway(Gangbyeonbuk-ro) and analyzed the difference in travel time between lanes. In addition, this study built a road network of the road section and proposed a shortest lane-path calculation method using this, and as a result of comparing the shortest and longest lane-path, there was a significant effect on the reduction of travel time according to the optimal choices of lanes when driving in uninterrupted roads.

Development of an evaluation index to evaluate the impact of public mobile apps with user participation

Woo Hoon Jeon(전우훈),Inchul Yang(양인철) 한국디지털콘텐츠학회 2018 한국디지털콘텐츠학회논문지 Vol.19 No.12

Many public agencies have been developing and operating various kinds of public mobile apps as the market penetration rate of smartphones exceeds 90%. The central government wanted to evaluate the impact of those apps to determine whether or not to maintain the services. However, it has been very difficult to find effective and quantitative measures. Therefore, evaluation indexes for public apps have been proposed in this study by analyzing the existing evaluation measures used by the government. Through the analysis, it was found that the increasing rate of use from the users’ perspective and the change rate of processing time from the managers’ perspective can be the representative measures. The measures have been applied to the respective services of the public apps. It was found that the increasing rate of use tends to converge below 5% and the change rate of processing time becomes stable around 45% after 3 years of operation.

딥러닝 기반 도로위험객체 인식 시스템 성능 향상 방법 개발

양인철(Inchul Yang),전우훈(Woo Hoon Jeon) 한국산학기술학회 2022 한국산학기술학회논문지 Vol.23 No.11

파손된 도로시설물, 로드킬 등의 도로위험객체는 교통사고 위험을 초래하기 때문에 신속하고 정확한 발견과 처리가 매우 중요하다. 이에 전국 도로의 유지관리를 총괄하는 국토교통부에서는 도로이용불편신고 서비스를 운영하고 있으며, 보다 안전하고 효율적인 신고 지원을 위해 이미지 기반의 자동 객체 인식 시스템을 개발 중이다. 시스템 개발은 여러 단계에 걸쳐 수행되고 있으며, 각 단계마다 인식률 향상을 위한 연구가 진행되고 있다. 이에 본 연구에서는 딥러닝 알고리즘을 활용하여 자동으로 도로위험객체를 인식하는 시스템의 성능을 향상시키는 체계적인 방법을 제안하고자 한다. 이를 위해 성능 향상 방법에 대한 절차를 제안하였고, 세부적인 원인 분석을 통해 새로운 솔루션(신경망 구조 변경, 데이터 정제 및 강화)을 제안하였다. 신경망 구조는 기존 YOLOv3보다 우수한 성능을 보이는 YOLOv5로 변경하였고, 데이터 강화를 위해 신고 이미지 중 문제점 확인이 어려운 이미지를 제외하였고, 신고 이미지 외에 오픈소스 이미지 데이터셋에서 양질의 이미지를 추가로 확보하였다. 이를 기존 시스템에 적용하여 신규 시스템을 개발하고, 그 성능을 검증하였다. 본 연구는 기존 시스템에서 인식률이 낮았던 도로시설물과 로드킬을 대상으로 하였으며, 새로운 시스템의 성능 검증을 통해 도로시설물과 로드킬 인식률이 각각 71%에서 91%로, 67%에서 97%로 향상됨을 확인하였다. 향후 제안된 성능 향상 방법에 따라 체계적인 시스템 성능 향상이 가능할 것으로 기대된다. Dangerous road objects cause traffic accidents, which makes it imperative to find and remove them quickly. For this purpose, MOLIT(Ministry of Land, Infrastructure, Transportation) is providing a smartphone app-based reporting service for dangerous road objects and is developing an automatic object recognition and classification system. The development project has several phases, and elaborate efforts have been put into every phase to improve its performance. A systematic method to improve the system performance was proposed in this study. The specific process was proposed, and new solutions(neural network, data manipulation) were found through factor analysis. The existing neural network, YOLOv3, was replaced by the better-performing neural network model, YOLOv5. Some reported images were difficult to designate as problems and were excluded, and high-quality images were also added from an open-source image dataset. The solutions were applied to the system, and its performance was validated. Road facilities and road kills were selected. The results showed that the performance improved the detection rates of road facilities and road kills from 71% to 91% and from 67% to 97%, respectively. The proposed method is expected to improve the system performance systematically.

정밀전자지도를 활용한 디지털 도로 이벤트 관리 시스템

양인철(Inchul Yang),전우훈(Woo Hoon Jeon) 한국디지털콘텐츠학회 2018 한국디지털콘텐츠학회논문지 Vol.19 No.11

A self-driving system aims to provide efficient and safe mobility to passengers by directly controling the driving system based on the comprehensive data collected by its own sensors as well as by communication devices, which are utilized to receive data from other ITS (Intelligent Transport System) stations such as traffic management center. So it is imperative to create and manage more accurate location data of road events, and thus we developed a digital road event management system (DREMS) which is able to manage more accurate location information of various kinds of road events on the road using a high-precision digital map. Firstly system requirements are analyzed through literature review and expert interview based on which the system architecture and user interface were carefully designed, followed by developing the prototype of DREMS. The system working test was conducted to create the digital road event data of a road work zone showing that the lane-level accurate data was created.

딥러닝 기반 도로위험객체 자동 인식 및 분류에 관한 연구

양인철(Inchul Yang),전우훈(Woo-Hoon Jeon),이조영(Joyoung Lee) 한국디지털콘텐츠학회 2021 한국디지털콘텐츠학회논문지 Vol.22 No.8

Various dangerous road objects such as potholes, falling objects, roadkills occur frequently on road, and the best way to prevent accidents from these dangers is to find them as soon as possible. A lot of mobile applications to report the road problems have been developed and in service worldwide both in public and private sectors. It is not safe, however, to report the problem using those apps in road environment, and it is necessary to develop a technology to minimize the time to make a report using the apps. For this purpose, a method to recognize and classify the road dangerous objects automatically from road images using deep learning algorithm was proposed and implemented, and the performance of the proposed model(YOLO v3) was tested, which shows 95% success rate on average to detect the four categories of road dangers including pavement, drainage, road facility, and roadkill, and demonstrates the possibility of the proposed method.

정밀전자지도 기반의 차로 수준의 위치정보 교환 프레임워크 개발

양인철(Inchul Yang),전우훈(Woo Hoon Jeon) 한국디지털콘텐츠학회 2018 한국디지털콘텐츠학회논문지 Vol.19 No.8

It is necessary to develop a next generation location referencing method with higher accuracy as advanced technologies such as autonomous vehicles require higher accuracy of location data. Thus, we proposed a framework for a lane-level location referencing method (L-LRM) based on high-precision digital road network map, and developed a tool which is capable of analyzing and evaluating the proposed method. Firstly, the necessity and definition of location referencing method was presented, followed by the proposal of an L-LRM framework with a fundamental structure of high-precision digital road network map for the method. Secondly, an architecture of the analysis and evaluation tool was described and then the Windows application program was developed using C/C++ programming language. Finally, we demonstrated the performance of the proposed framework and the application program using two different high precision digital maps with randomly generated road event data.

차량센서를 활용한 교통 상태 관측 기술 개발

양인철(Inchul Yang),전우훈(Woo Hoon Jeon) 한국디지털콘텐츠학회 2018 한국디지털콘텐츠학회논문지 Vol.19 No.11

It is required for traffic congestion relief and safety improvement as well as for self-driving vehicle development to develop an efficient and accurate traffic state observation technology. In addition, the sensing technology is rapidly developing and various types of automotive sensors are adopted to enable ADAS(Advanced Driving Assistant System) in some high-end vehicles. In this regard, we proposed a traffic state observation system using automotive sensors. Widely used automotive sensors were investigated to understand their features, and then some literature on traffic state was reviewed. Six system requirements have been listed, and the system architecture was designed in consideration of the characteristics of sensors and the experts’ opinion. The user interface was carefully designed under assumption of a traffic state observation system with radar, video camera, and GPS. Finally the prototype of the system was developed and tested, and the results show that the proposed system works well.

자전거도로의 인프라 데이터 구축을 위한 설계지표 연구

전우훈(Woo Hoon Jeon),양인철(Inchul Yang) 한국콘텐츠학회 2020 한국콘텐츠학회논문지 Vol.20 No.12

본 연구의 목적은 자전거도로의 인프라 데이터 구축을 위한 지표를 선정하고자 함이며, 이를 위해 기존의 자전거도로와 관련된 설계기준 분석을 통해 지표를 도출하였다. 자전거도로의 설계요소가 제시되어 있는 중앙정부 및 지방정부의 설계기준 및 지침을 바탕으로 자전거도로의 속성데이터를 교통, 기하구조, 포장, 안전시설 및 부대시설 등 4개로 구분하여 분석하였다. 도출된 지표는 도로 및 교통분야 전문가들을 대상으로 FGI(Focus Group Interview)을 통한 브레인스토밍을 진행하였으며, 도출된 지표 이외의 추가적인 지표까지 의견을 수렴하였다. 최종적으로 필수 설계요소는 설계속도 및 도로유형, 포장유형, 교통안전시설 등 총 24개가 선정되었으며, 추가 설계요소는 버스/택시 정류장 및 미끄럼저항성(BPN) 등 6개가 선정되었다. 본 연구에서 제시된 24개의 자전거도로대장 지표는 법 개정이 이루어질 경우 반드시 포함되어야 하는 요소로 판단되며, 향후 도로 및 교통전문가 및 도로관리청 등의 의견수렴을 통해 추가적인 6개 지표의 포함여부를 판단할 수 있을 것으로 기대된다. The purpose of paper is to find index for building digital database of bike infrastructure statistics by analyzing the existing design standards and manuals. The design standards and guides of both central and local governments which designates the design elements of bikeway were investigated to find the primary index, and then the attribute data of bikeway were grouped into four categories including transportation, geometry, pavement, safety and utility facility, and were analyzed to find the secondary index. A FGI(Focus Group Interview) was conducted with experts in the arena of transportation to collect the opinions on the selected index. It is found that the final twenty four design elements were selected and additional six elements were added. The proposed twenty four index of bikeway design elements are considered to be included when building the digital bikeway register database.

위치정보 기반의 국민참여형 도로불편 신고 앱 UI 개발 및 효과분석

전우훈(Woo Hoon Jeon),양인철(Inchul Yang) 한국디지털콘텐츠학회 2018 한국디지털콘텐츠학회논문지 Vol.19 No.10

The number of road accidents due to unexpected events (a.k.a incident) such as potholes has been increased. However it is very difficult for road managers to maintain the high level of road conditions due to the limited human and monetary resources. In addition road users who want to report road problems can hardly find an easy way to do. In this regard, we proposed a novel user interface (UI) of smartphone based application which is capable of reporting road problems using the smartphone GPS(Global Positioning System) functionality with digital maps in a server system. A survey was conducted, and five kinds of user complaints was investigated. Based on the results, several app functions were developed to meet the requirements. After four years of the service operation, it is found that the users’ satisfaction level demonstrates the effectiveness and easiness of the proposed UI.