• Title/Summary/Keyword: mapping method

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A Study on Communication Controller of Electric Vehicle Supply Equipment for Information Exchange between Electric Vehicle and Power Grid (전기차와 전력계통의 정보교환을 위한 전기차 충전장치의 통신 제어기에 대한 연구)

  • Han, Ah;Shin, Minho;Kim, Intaek;Jang, Hyuk-Soo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.11
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    • pp.1564-1570
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    • 2014
  • An electric vehicle (EV) not only receives electric power from the electric vehicle supply equipment (EVSE), but it also exchanges the information regarding charging process with the power gird through the EVSE. However, the EV and EVSE communicate using the ISO/IEC 15118 standard while the EVSE and power grid communicate using the IEC 61850 standard. Therefore, the EVSE should support both the ISO/IEC 15118 and IEC 61850 standards, and provide a data mapping function between the two communication protocols so that the EV and power grid, which support different protocols, can communicate with each other throughout the charging process. In this paper, we propose a mapping method of the EVSE, which converts the ISO/IEC 15118 data to IEC 61850 and vice versa, based on the XML schema of each protocol. The proposed method converts the data using the XSL (eXtensible Stylesheet Language) method, which defines the data mapping between two XML schemas. Our approach is more flexible and easier to maintain against changes in charging scenarios and the standards than other existing approaches such as one-to-one data mapping methods.

PAPR reduction effects in the OFDM by the modified QPSK signal mapping method (OFDM 시스템에서 변형된 QPSK 신호 매핑 방법에 의한 PAPR 감소 효과)

  • 성백민;이우재;주창복
    • Journal of the Institute of Convergence Signal Processing
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    • v.3 no.2
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    • pp.58-63
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    • 2002
  • One of the important problems of OFDM system is the large PAPR of the output signal, which can result the significant signal distortion in presence of nonlinear amplifiers. To reduce the PAPR, we use fundamentally the level clipping and propose the modified mapping/demapping method for effective reducing the PAPR of the OFDM signals with level clipping. We can significantly improve the BER performance characteristics for the OFDM system. We discussed, through extensive computer simulations, the effects of level clipping and modified mapping/demapping method on the performance of OFDM system including the trade off between bandwidth expansion and BER performance and between bandwidth efficiency and BER performance.

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ShEx Schema Generator for RDF Graphs Created by Direct Mapping

  • Choi, Ji-Woong
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.10
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    • pp.33-43
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    • 2018
  • In this paper, we propose a method to automatically generate the description of an RDF graph structure. The description is expressed in Shape Expression Language (ShEx), which is developed by W3C and provides the syntax for describing the structure of RDF data. The RDF graphs to which this method can be applied are limited to those generated by the direct mapping, which is an algorithm for transforming relational data into RDF by W3C. A relational database consists of its schema including integrity constraints and its instance data. While the instance data can have been published in RDF by some standard methods such as the direct mapping, the translation of the schema has been missing so far. Unlike the users on relational databases, the ones on RDF datasets were forced to write repeated vague SPARQL queries over the datasets to acquire the exact results. This is because the schema for RDF data has not been provided to the users. The ShEx documents generated by our method can be referred as the schema on writing SPARQL queries. They also can validate data on RDF graph update operations with ShEx validators. In other words, they can work as the integrity constraints in relational databases.

Efficient Method to Estimate the Number of Exposed People to Industrial Noise Using the GIS and Three Dimensional Noise Mapping - Focusing on the Industrial Noise - (GIS와 3차원 소음지도를 이용한 소음 노출 인구 산정 방법에 관한 연구 - 공장 소음을 중심으로 -)

  • Ko, Joon-Hee;Chun, Hyung-Joon;Chang, Seo-Il
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.17 no.6 s.123
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    • pp.491-497
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    • 2007
  • Reasonably accurate estimation of the exposed population to the distinct levels of noise is essential to the efficient management of urban environmental noise. This study proposes a method of calculating the number of exposed people to industrial noise by using GIS tool and noise mapping. The exposed population of noise based on estimation of the number of people that lived in each building in urban area is compared with the one based on density of population. This study suggests the five step method that consists of gathering the fundamental data, extracting the property from the digital map, noise mapping based on the three dimensional topography, estimating population that lives in each building, merging the various results with GIS tool, and estimating exposed population to industrial noise through analyzing the noise map with GIS tools.

Aerostatic pressure of streamlined box girder based on conformal mapping method and its application

  • Wu, Lianhuo;Ju, J. Woody;Zhang, Mingjin;Li, Yongle;Qin, Jingxi
    • Wind and Structures
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    • v.35 no.4
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    • pp.243-253
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    • 2022
  • The conformal mapping method (CMM) has been broadly exploited in the study of fluid flows over airfoils and other research areas, yet it's hard to find relevant research in bridge engineering. This paper explores the feasibility of CMM in streamlined box girder bridges. Firstly, the mapping function transforming a unit circle to the streamlined box girder was solved by CMM. Subsequently, the potential flow solution of aerostatic pressure on the streamlined box girder was obtained and was compared with numerical simulation results. Finally, the aerostatic pressure attained by CMM was utilized to estimate the aerostatic coefficient and flutter performance of the streamlined box girder. The results indicate that the solution of the aerostatic pressure by CMM on the windward side is satisfactory within a small angle of attack. Considering the windward aerostatic pressure and coefficient of correction, CMM can be employed to estimate the rate of change of the lift and moment coefficients with angle of attack and the influence of the geometric shape of the streamlined box girder on flutter performance.

Image Dependent Gamut Mapping Using the Variable Anchor Point Based on the change of lightness (휘도값 변화에 기초하여 가변하는 앵커점을 이용한 영상 의존 색역 사상 방법)

  • Kim, Shin-Dong;Kim, Kyeong-Man;Lee, Chae-Soo;Lee, Cheol-Hee;Ha, Yeong-Ho
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.1
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    • pp.38-50
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    • 1999
  • Currently many devices reproduce electronic images in the various ways. However the color that is reproduced in any device is different from the original color due to the difference in the gamut between devices. In this paper, an image dependent gamut mapping method is proposed. This method clips the chroma with compensating for the change of lightness caused by the lightness scaling. The anchor point, which is the center point in the mapping, is set as a lower point by the proposed method than a point by the conventional mapping method. This reduces the color difference between point. In addition, to heighten the color contrast on the constant hue, the different two mapping methods are applied to the printer gamut which is divided in two region, bright region and dark region. Consequently, the printer output image was highly consistent with the corresponding monitor image.

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Efficient Reverse Tone Mapping Method Using Guided Filter (Guided Filter를 사용한 효율적인 Reverse Tone Mapping 기법)

  • Kim, Sang Hyub;Lee, Chang Woo
    • Journal of Broadcast Engineering
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    • v.23 no.2
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    • pp.283-292
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    • 2018
  • Devices capable of capturing and displaying high dynamic range (HDR) images with significantly increased brightness range compared to low dynamic range (LDR) images have been developed and various methods for efficiently converting the brightness range of an image have been developed. In this paper, we propose a reverse tone mapping method using a guided filter to efficiently convert LDR images into HDR images. After obtaining brightness enhancement function (BEF) using a guided filter, we can reconstruct HDR image from one LDR image. In addition, when the image is too bright or dark, the proposed method maximizes the image quality of the reconstructed HDR image by estimating and adjusting the exposure value before expanding the brightness range of images. Computer simulations show that the proposed method produces HDR images of superior quality compared with the conventional methods.

Design of an Effective Bump Mapping Hardware Architecture Using Angular Operation (각 연산을 이용한 효과적인 범프 매핑 하드웨어 구조 설계)

  • 이승기;박우찬;김상덕;한탁돈
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.11
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    • pp.663-674
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    • 2003
  • Bump mapping is a technique that represents the detailed parts of the object surface, such as a perturberance of the skin of a peanut, using the geometry mapping without complex modeling. However, the hardware implementation for bump mapping is considerable, because a large amount of per pixel computation, including the normal vector shading, is required. In this paper, we propose a new bump mapping algorithm using the polar coordinate system and its hardware architecture. Compared with other existing architectures, our approach performs bump mapping effectively by using a new vector rotation method for transformation into the reference space and minimizing illumination calculation. Consequently, our proposed architecture reduces a large amount of computation and hardware requirements.

Directions for Forest Functions Mapping in Korea (산림녹지기능도의 도입 방향)

  • 변무섭;최만봉;김계환
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.5
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    • pp.101-114
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    • 2001
  • This study analyzed and examined literature and legislation in Korean and other countries to examine the concept and sense of mapping of forest functions that would be used as basic information for efficient application and management of forest ecosystems. The mapping of forest functions in Germany has been utilized to field data for efficient work and management of the ecosystem, and evaluation of forest environmental ecology by the mapping of forest functions has been applied directly or indirectly in country management plans, conservation of nature and landscape management plans. Forest protection areas in Korea were analysed for creating a map of forest functions. As the results, forest functions could be sorted into five categories, such as conservation area of forest production, prevention of disasters, landscape and abiological natural resource, valuable biotope and ecosystem and civil recreation. The mapping method was applied to these 5 categories important conservation targets. It is considered that mapping of forest functions in Korea can be used for systematic forest works and efficient ecosystem utilization and management, as well as it use basic data for environmental and ecological comprehension and evaluation on forest and green tract of land on the level of country development and utilization.

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Multi-robot Mapping Using Omnidirectional-Vision SLAM Based on Fisheye Images

  • Choi, Yun-Won;Kwon, Kee-Koo;Lee, Soo-In;Choi, Jeong-Won;Lee, Suk-Gyu
    • ETRI Journal
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    • v.36 no.6
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    • pp.913-923
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    • 2014
  • This paper proposes a global mapping algorithm for multiple robots from an omnidirectional-vision simultaneous localization and mapping (SLAM) approach based on an object extraction method using Lucas-Kanade optical flow motion detection and images obtained through fisheye lenses mounted on robots. The multi-robot mapping algorithm draws a global map by using map data obtained from all of the individual robots. Global mapping takes a long time to process because it exchanges map data from individual robots while searching all areas. An omnidirectional image sensor has many advantages for object detection and mapping because it can measure all information around a robot simultaneously. The process calculations of the correction algorithm are improved over existing methods by correcting only the object's feature points. The proposed algorithm has two steps: first, a local map is created based on an omnidirectional-vision SLAM approach for individual robots. Second, a global map is generated by merging individual maps from multiple robots. The reliability of the proposed mapping algorithm is verified through a comparison of maps based on the proposed algorithm and real maps.