• Title/Summary/Keyword: global position system

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Long-term shape sensing of bridge girders using automated ROI extraction of LiDAR point clouds

  • Ganesh Kolappan Geetha;Sahyeon Lee;Junhwa Lee;Sung-Han Sim
    • Smart Structures and Systems
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    • v.33 no.6
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    • pp.399-414
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    • 2024
  • This study discusses the long-term deformation monitoring and shape sensing of bridge girder surfaces with an automated extraction scheme for point clouds in the Region Of Interest (ROI), invariant to the position of a Light Detection And Ranging system (LiDAR). Advanced smart construction necessitates continuous monitoring of the deformation and shape of bridge girders during the construction phase. An automated scheme is proposed for reconstructing geometric model of ROI in the presence of noisy non-stationary background. The proposed scheme involves (i) denoising irrelevant background point clouds using dimensions from the design model, (ii) extracting the outer boundaries of the bridge girder by transforming and processing the point cloud data in a two-dimensional image space, (iii) extracting topology of pre-defined targets using the modified Otsu method, (iv) registering the point clouds to a common reference frame or design coordinate using extracted predefined targets placed outside ROI, and (v) defining the bounding box in the point clouds using corresponding dimensional information of the bridge girder and abutments from the design model. The surface-fitted reconstructed geometric model in the ROI is superposed consistently over a long period to monitor bridge shape and derive deflection during the construction phase, which is highly correlated. The proposed scheme of combining 2D-3D with the design model overcomes the sensitivity of 3D point cloud registration to initial match, which often leads to a local extremum.

Discussion of Alternatives for Inter-Korean Mobile Communication Cooperation in the era of 5G Technology (5G시대, 남북한 이동통신 협력 대안 논의)

  • Lee, Jeong-Jin
    • Informatization Policy
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    • v.29 no.1
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    • pp.84-102
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    • 2022
  • Changes have been taking place in North Korea, which has been pushing for selective informatization with a priority on a system safety. North Korea has been developing its own mobile communication industry over the past decade by expanding base stations, producing smartphones on its own, and developing applications useful in real life. Recently, the introduction of 5G technology has been elevated to the status of a national agenda to be fostered as a key industry for national economic development. The time has arrived when the needs of North Korea, which has to advance technology, are aligned with the capabilities of South Korean mobile communication companies, which are seeking to new markets to overcome stagnant growth. The purpose of this paper is to illustrate a cooperative scenario for mobile communications companies between the two Koreas in the early stages of the 4th Industrial Revolution and its core technology 5G, while also making a timely proposal to position North Korea in the GVC. Mobile communications is a large-scale industry that can create synergies from inter-Korean economic cooperation by facilitating exchanges and cooperation between the two Koreas, inducing numerous derivative industries and driving job creation. Joint mobile communications activities with North Korea would be an effective cooperative aspect that can contribute to the economic prosperity of the entire Korean Peninsula.

Analysis for Accuracies of Position Fix by GPS in Kusan Area (군산지역에서의 GPS측위정도 해석)

  • LEE Won-Woo;SHIN Hyeong-Il;LEE Dae-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.3
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    • pp.250-257
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    • 1993
  • The Global Positioning System(GPS) is a worldwide radio navigation system based on satellite technology. Signal availability and accuracy of GPS are subject to change due to an incomplete constellation and operational test activities. In order to analyze the signal availability and accuracy of GPS, we made an experiment on this system in Kunsan during April 6, 7, 9, 10, 1992. The results obtained are summarized as follows: 1. It was possible to avail the GPS system almost 24 hours per day, but sometimes it was impossible to obtain the GPS signal 2 or 3 times per day and its total time was at the most an hour. 2. By using satellite almanac, we also could calculate PDOP(HDOP) and forecast signal availability. And the mean positional error was $37.9{\sim}73.6m$ and standard deviation was $37.4{\sim}133.1m$. The positional error almost coincided with PDOP(HDOP). 3. The mean positional error of 3D was less than that of 2D. And the altitude error in 3D was about $56{\sim}74m$ and its standard deviation was about $65{\sim}93m$.

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Feasibility Study on the Methodology of Test and Evaluation for UAV Positioning (무인항공기 위치정확도 시험평가 기법 연구)

  • Ju, Yo-han;Moon, Kyung-kwan;Kang, Bong-seok;Jeong, Jae-won;Son, Han-gi;Cho, Jeong-hyun
    • Journal of Advanced Navigation Technology
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    • v.22 no.6
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    • pp.530-536
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    • 2018
  • Recently, many studies for interoperability of UAV in the NAS has been performed since the application range and demand of UAV are continuously increased. For the interoperation of UAV in the NAS, technical standards and certification system for UAV which is equivalent to the commercial aircraft are required and test and evaluation methodology must be presented by standards. In this paper, qualification test and evaluation methodology aboutfor the UAV navigation system is proposed. For the research, the mission profile and operation environment of UAV were analyzed. Thereafter the test criteria were derived and the test methodology were established. Finally, the simulation and demonstration using test-bed UAV were performed. As a result of the test, it was confirmed that the navigation system of test UAV has a position accuracy about 1.4 meters at 95% confidence level in the entire flight stage.

Comparison of ESG Evaluation Methods: Focusing on the K-ESG Guideline (ESG 평가방법 비교: K-ESG 가이드라인을 중심으로)

  • Chanhi Cho;Hyoung-Yong Lee
    • Journal of Intelligence and Information Systems
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    • v.29 no.1
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    • pp.1-25
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    • 2023
  • ESG management is becoming a necessity of the times, but there are about 600 ESG evaluation indicators worldwide, causing confusion in the market as different ESG ratings were assigned to individual companies according to evaluation agencies. In addition, since the method of applying ESG was not disclosed, there were not many ways for companies that wanted to introduce ESG management to get help. Accordingly, the Ministry of Trade, Industry and Energy announced the K-ESG guideline jointly with the ministries. In previous studies, there were few studies on the comparison of evaluation grades by ESG evaluation company or the application of evaluation diagnostic items. Therefore, in this study, the ease of application and improvement of the K-ESG guideline was attempted by applying the K-ESG guideline to companies that already have ESG ratings. The position of the K-ESG guideline is also confirmed by comparing the scores calculated through the K-ESG guideline for companies that have ESG ratings from global ESG evaluation agencies and domestic ESG evaluation agencies. As a result of the analysis, first, the K-ESG guideline provide clear and detailed standards for individual companies to set their own ESG goals and set the direction of ESG practice. Second, the K-ESG guideline is suitable for domestic and global ESG evaluation standards as it has 61 diagnostic items and 12 additional diagnostic items covering the evaluation indicators of global representative ESG evaluation agencies and KCGS in Korea. Third, the ESG rating of the K-ESG guideline was higher than that of a global ESG rating company and lower than or similar to that of a domestic ESG rating company. Fourth, the ease of application of the K-ESG guideline is judged to be high. Fifth, the point to be improved in the K-ESG guideline is that the government needs to compile industry average statistics on diagnostic items in the K-ESG environment area and publish them on the government's ESG-only site. In addition, the applied weights of E, S, and G by industry should be determined and disclosed. This study will help ESG evaluation agencies, corporate management, and ESG managers interested in ESG management in establishing ESG management strategies and contributing to providing improvements to be referenced when revising the K-ESG guideline in the future.

A Real-Time Head Tracking Algorithm Using Mean-Shift Color Convergence and Shape Based Refinement (Mean-Shift의 색 수렴성과 모양 기반의 재조정을 이용한 실시간 머리 추적 알고리즘)

  • Jeong Dong-Gil;Kang Dong-Goo;Yang Yu Kyung;Ra Jong Beom
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.6
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    • pp.1-8
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    • 2005
  • In this paper, we propose a two-stage head tracking algorithm adequate for real-time active camera system having pan-tilt-zoom functions. In the color convergence stage, we first assume that the shape of a head is an ellipse and its model color histogram is acquired in advance. Then, the min-shift method is applied to roughly estimate a target position by examining the histogram similarity of the model and a candidate ellipse. To reflect the temporal change of object color and enhance the reliability of mean-shift based tracking, the target histogram obtained in the previous frame is considered to update the model histogram. In the updating process, to alleviate error-accumulation due to outliers in the target ellipse of the previous frame, the target histogram in the previous frame is obtained within an ellipse adaptively shrunken on the basis of the model histogram. In addition, to enhance tracking reliability further, we set the initial position closer to the true position by compensating the global motion, which is rapidly estimated on the basis of two 1-D projection datasets. In the subsequent stage, we refine the position and size of the ellipse obtained in the first stage by using shape information. Here, we define a robust shape-similarity function based on the gradient direction. Extensive experimental results proved that the proposed algorithm performs head hacking well, even when a person moves fast, the head size changes drastically, or the background has many clusters and distracting colors. Also, the propose algorithm can perform tracking with the processing speed of about 30 fps on a standard PC.

A Study on the Successful Case of Brand Renewal through American National Brand 'C' Company's Marketing Strategy (미국(美國) 내셔널브랜드 C사(社)의 마케팅전략(戰略)을 통한 브랜드리뉴얼 성공사례(成功事例) 연구(硏究))

  • Koh, Hee-Sook
    • Journal of Fashion Business
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    • v.6 no.1
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    • pp.137-154
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    • 2002
  • It's not easy to renew old brand of over 50 years history to the tastes of new consumer of our time. Most of national brands that has a history of some 20 years in Korea have strove for continuation and growth of brand to no avails, which can be taken as a good example of current situation. For instance, C company, one of the National brand of US which has a history of 51 years, has made its position secure as a fashion group and based itself on a sound foundation by establishing new marketing strategy and completing successful brand renewal in the process of strategic M&A with Italian company. Those successful marketing strategies are as follows. 1) they regarded both market and consumer oriented marketing activity as company's highest priority strategy and put great emphasis upon concentration on target market and reestablishment of brand image of business casual wear. 2) Setting up and operating planning team composed of merchandizer alone in Milano, they set the direction of plan on the basis of concentrated research on potential item in market according to thorough market research done by buying office in Korea, branch office in Hong Kong and buyer in US prior to blueprint planning for season. 3) Great emphasis was placed on business which focused on intensive presentation of basic key item for apparel career women who are main consumer group in the midium-low prices market in US and on supplementation of size and color. they named this line 'collectibles' and helped their customer develop their own clothes plan without worrying about the change of color and fabric by supporting same fabric and color throughout the year and enabled them to add variation easily by supplementing new trend item. 4) Company set black as a main color that lots of apparel career women find easy to care and to express their own image and presented them with pebble which belongs to navy and beige and added fashion color such as wine and brown etc as season goes by. They constructed basic line in order for their customers to coordinate purchased item with new one or to add them to present collection, and to achieve efficient sale by setting up strategy which allows this cross coordination and changing pattern occasionally. 5) Though basic jacket for 99$, short slim skirt for 49$ are products within midium-low prices range, in the material planning stage aiming at production of item that has both resonable function appealing to consumer and is fashionable, synthetic material had to be used as a main source due to price competitiveness. Despite this situation, considering comfortable sense of fit and refined drape of silhouette that has no sign of cheap material, whole collectible line was divided into two items, which contributed to reduction of cost. In case of material that is composed of triacetate and polyester in 70 to 30 ratio, was used up to 4 million yard, which allowed drastic curtailment of cost accompanied by concentration. In case of 'collectibles' line, using Korean material mainly, C company chose to have their product sewed in Southeast Asian countries where transportation is well developed and both productivity and quality verified by operating global production system which aiming at cutdown of cost through outsourcing production from the country where labor cost is low and getting finished product. Polarization between present consumers telling us that consumers with the mind of middle classes in the past no longer exists between consumers who seek after only fine article of highest quality and wise consumers who are sensible enough to judge bubble on correlation between price and quality. To cope with this change in new consumer mind, apparel makes changing their policy so as to produce item that has reasonable quality and falls within affordable price range anywhere in the world. and they're striving to get out of difficult situation by operating global marketing strategy which stresses separation of planning, production and sale and sensibility of fashion shared worldwide. The marketing strategy of C company can be exemplified as a successful one.

A Study on Red Tide Monitoring system using Wireless Sensor Network (무선센서네트워크를 이용한 적조모니터링 시스템 구축을 위한 연구)

  • Min Heo;Mo Soo-Jong;Yim Jae-Hong;Kim Ki-Moon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.489-492
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    • 2006
  • Red tide occurred sporadically in early 90s. But It is happening extensively by global warming. So, Airline observation, Red tide buoy development, and Red tide alarm system research is progressing for monitor ring. However, study to early forecast red tide and red tide alarm system did not exist hard. This paper proposed development that design and implementation red tide database of using wireless sensor network. There are GPS, Water Temperature sensor, Oxygen sensor, and Turbidity sensor in each node. And data is stored to red tide database through Ad-hoc network. This data is integrated and analyzed. So, forecast red tide. And red tide database has red tide data that happen at past. This is utilized to comparative analysis data for red tide estimate. Main screen displays position of node and measured value in electron map. Much studies must be backed for this a study. But I think that contribute to analyze red tide data by red tide database construction.

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Accuracy Analysis of Low-cost UAV Photogrammetry for Road Sign Positioning (드론사진측량에 의한 도로표지 위치정보 정확도 평가)

  • Sung, Hongki;Chong, Kyusoo;Lee, Chang No
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.4
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    • pp.243-251
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    • 2019
  • The road sign location information installed on national roads is continuously updated using MMS (Mobile Mapping System) technology. It is possible to map accurate road facilities by MMS, but the equipment is very expensive and requires specialized technology. Also, the accuracy of the position of the object greatly depends on the GPS (Global Positioning System) accuracy. In the case of road facility mapping, the advantage of drone is more remarkable than that of field survey or conventional aerial photogrammetry. In particular, it is more efficient than field surveying and it is possible to acquire high resolution images with low budget compared to conventional aerial photogrammetry. In this study, the accuracy of the location information measured by the existing MMS is compared with the GPS survey result and the accuracy analysis is performed by the drone aerial photogrammetry. In order to confirm the space accuracy that can be obtained when conducting drone aerial photogrammetry, the accuracy of the change in the number of ground control points and the degree of overlap was evaluated. As a result of the experiment, it was possible to obtain sufficient accuracy with two ground control points distributed at both ends of the road and 60% overlap.

Localization using Neural Networks and Push-Pull Estimation based on RSS from AP to Mobile Device (통신기지국과 모바일장치간의 수신신호강도를 기반으로 하는 신경망과 푸쉬-풀 평가를 이용한 위치추정)

  • Cho, Seong-Jin;Lee, Sung-Young
    • The KIPS Transactions:PartD
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    • v.19D no.3
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    • pp.237-246
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    • 2012
  • Although the development of Global Positioning System (GPS) are more and more mature, its accuracy is just acceptable for outdoor positioning, not positioning for the indoor of building and the underpass. For the positioning application area for the indoor of building and the underpass, GPS even cannot achieve that accuracy because of the construction materials while the requirement for accurate positioning in the indoor of building and the underpass, because a space, a person is necessary, may be very small space with several square meters in the indoor of building and the underpass. The Received Signal Strength (RSS) based localization is becoming a good choice especially for the indoor of building and the underpass scenarios where the WiFi signals of IEEE 802.11, Wireless LAN, are available in almost every indoor of building and the underpass. The fundamental requirement of such localization system is to estimate location from Access Point (AP) to mobile device using RSS at a specific location. The Multi-path fading effects in this process make RSS to fluctuate unpredictably, causing uncertainty in localization. To deal with this problem, the combination for the method of Neural Networks and Push-Pull Estimation is applied so that the carried along the devices can learn and make the decision of position using mobile device where it is in the indoor of building and the underpass.