• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.39 no.3
• /
• pp.133-139
• /
• 2021

Currently, the process of constructing a high-definition road map has a high proportion of manual labor, so there are limitations in construction time and cost. Research to automate map production with high-definition road maps using artificial intelligence is being actively conducted, but since the construction of training data for the map construction is also done manually, there is a need to automatically build training data. Therefore, in this study, after converting to images using point clouds acquired by a mobile mapping system, the road marking areas were extracted through image reclassification and overlap analysis using thresholds. Then, a methodology was proposed to automatically construct training data for deep learning data for the high-definition road map through the classification of the polygon types in the extracted regions. As a result of training 2,764 lane data constructed through the proposed methodology on a deep learning-based PointNet model, the training accuracy was 99.977%, and as a result of predicting the lanes of three color types using the trained model, the accuracy was 99.566%. Therefore, it was found that the methodology proposed in this study can efficiently produce training data for high-definition road maps, and it is believed that the map production process of road markings can also be automated.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.5
• /
• pp.1958-1968
• /
• 2015

In this paper, a new definition of short-circuit ratio concept for multi-converter HVDC systems is proposed. Analysis results of voltage interaction between converters show that the reactive power-voltage characteristic of a converter has a dominant effect on voltage interaction level compared with its active power-voltage characteristic. Such a relation between converter reactive power and voltage interaction level supports taking the former into account in the definition of short-circuit ratio concept for multi-converter systems. The proposed definition is verified by the method of maximum power curve for various system configurations. Furthermore, a formula to calculate transient overvoltage for multi-converter systems is derived based on the proposed definition, and the efficiency of the derived formula is verified.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.39 no.6
• /
• pp.363-369
• /
• 2021

High-definition road maps are used as the basic infrastructure for autonomous vehicles, so the latest road information must be quickly reflected. However, the current drawing and structural editing process of high-definition road maps are manually performed. In addition, it takes the longest time to generate road lanes, which are the main construction targets. In this study, the point cloud of the road lane markings, in which color types(white, blue, and yellow) were predicted through the PointNet model pre-trained in previous studies, were used as input data. Based on the point cloud, this study proposed a methodology for automatically drawing and structural editing of the layer of road lane markings. To verify the usability of the 3D vector data constructed through the proposed methodology, the accuracy was analyzed according to the quality inspection criteria of high-definition road maps. In the positional accuracy test of the vector data, the RMSE (Root Mean Square Error) for horizontal and vertical errors were within 0.1m to verify suitability. In the structural editing accuracy test of the vector data, the structural editing accuracy of the road lane markings type and kind were 88.235%, respectively, and the usability was verified. Therefore, it was found that the methodology proposed in this study can efficiently construct vector data of road lanes for high-definition road maps.

• The Mathematical Education
• /
• v.61 no.2
• /
• pp.323-338
• /
• 2022

The purpose of this study are to analyze how well middle and high school students understand the concept definition of quadrangle and to explore the phenomenon about their concept image. A test tool was developed and 60 8th graders, 63 9^th graders and 65 10^th graders were tested, and some students who needed in-depth analysis were interviewed. The results are as follows. First, it cannot be said that understanding level of the concept definition of the quadrangle naturally improves as the grade level goes up. Particularly, it was found that the understanding of the definition of the rhombus is the lowest in all three grades compared to other quadrangle. Second, although female students understood the definition of square better than male students, the understanding level of the definition of trapezoid, parallelogram, rhombus, and rectangle did not differ by gender. Third, it was found that the students who did not understand the concept definition of the quadrangle were more and more influenced by the concept image as the grade level went up. Fourth, it showed that a tendency to be less influenced by the concept definition and more influenced by textbooks and teachers as the grades go up when students form a concept image.

• Korean Journal of Construction Engineering and Management
• /
• v.23 no.1
• /
• pp.54-63
• /
• 2022

In order to derive the success factors of a Mega-scale national project, this study conducted a questionnaire survey on experts participating in the Yongsan National Park development program to obtain critical success factors in the program definition phase. AHP analysis was performed for each category through a survey of experts participating in the definition phase of the Yongsan park development program to derive relative importance. The categories were classified into program strategy, process, and people, and the importance between categories was people, strategy, and process in that order. In addition, as for the 27 critical success factors in the program definition phase, the program manager's competency and leadership, environmental and cultural property survey planning, program management plan preparation, operation and maintenance philosophy, and integrated program office showed high priorities. Therefore, in promoting the Yongsan Park development program, we propose a strategy for selecting and focusing on the critical success factors with high priorities in the program definition phase proposed in this study.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.81-85
• /
• 2006

The ultra-high definition TV system nicknamed "Super Hi-Vision" is a television system with 4000-scanning-line video and 22.2 multichannel sound. NHK has been developing it with the aim of creating a broadcasting system conveying a strong sensation of presence. We believe that it is important to design the system by taking into account human factors such as human visual system characteristics. This paper describes the psychological and physiological experiments on the visual effects of "Super Hi-Vision".

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.05a
• /
• pp.513-515
• /
• 2014

Ultra High Definition(hereafter UHD), Next-generation video technology, was quickening in the request of many years of the recipient and the authors who have been towards the higher sense of reality. The change of the medium has resulted in a mutation in the detailed content and the point of view overlooking the world as evidenced through the history. Thus the emergence of UHD will also be expected to require to manufacture unique technology. Therefore, this paper, especially in the documentary among the video content, tries to study the changes in the manufacturing process by UHD video technology. Moreover UHD video screen technology such as high resolution tries to analyse for the fitness for purpose of the documentary that transmission of the accuracy and the change from a documentary video production. In addition, I try to explore the improvement in the choice of shooting material expected to be a problem, even for the advance of the work on the second half and backup according to the enormous data. We derive the developmental aspects that UHD video technology in documentary production is brought about by the research plan described above. It is intended to contribute to the development of content production with the development of technology.

• Journal of Broadcast Engineering
• /
• v.25 no.6
• /
• pp.836-844
• /
• 2020

A very large number of pixels is required to generate a computer generated hologram (CGH) with a large-size and wide viewing angle equivalent to that of an analog hologram, which incurs a very large amount of computation. For this reason, a high-performance computing device and long computation time were required to generate high-definition CGH. To solve these problems, in this paper, we propose a technique for generating high-definition CGH by arraying the pre-calculated low-definition CGH and multiplying the appropriately-shifted concave lens function. Using the proposed technique, 0.1 Gigapixel CGH recorded by the point cloud method can be used to calculate 2.5 Gigapixels CGH at a very high speed, and the recorded hologram image was successfully reconstructed through the experiment.

• Proceedings of the IEEK Conference
• /
• 2003.07e
• /
• pp.1956-1959
• /
• 2003

본 논문에서는 HDTV(High Definition TV) 방송수신을 위한 DSP(Digital Signal Processor)기반의 HD급 비디오/오디오 디코더 시스템을 개발하고 그 성능을 확인하였다. DSP 플랫폼은 TI(Texas Instrument)사의 TMS320C6415를 대상으로 하였으며 TI의 DSP RTOS인 DSP/ BIOS를 이용하여 방송스트림인 TS(Transport Stream)을 분리하기 위한 TS Demuxer, MPEG-2 비디오 디코더 및 AC-3 오디오디코더 알고리즘을 통합하였으며, 각각의 알고리즘은 대상 DSP플랫폼인 TMS320C64x에 맞게 고정소수점 구조화 및 최적화를 실시하였다. 테스트를 위한 시스템은 스트리밍을 위한 호스트 PC와 PCI(Peripheral Component Interconnect)버스를 통해 연결된 DSP보드로 구성하였으며 실제 HDTV당송용 스트림과 SD(Standard Definition)급 스트림을 이용하여 성능을 확인하였다.

• Journal of the Architectural Institute of Korea Planning & Design
• /
• v.34 no.6
• /
• pp.135-142
• /
• 2018

A public pedestrian passage induces traffic into the apartment complex, and therefore, it requires the application of Crime Prevention Through Environmental Design(CPTED). This paper aims to analyze the conditions and to suggest the improvements of public pedestrian passages in apartment complexes, applying a 3-D approach from CPTED aspect. The first aspect is "Designation": 1)The linkage between the public pedestrian passages is weak, and their designated purpose becomes unclear. 2)When the designated purpose is not considered for each complex, the closure rate is high. 3)The closure rate of the "Through type" is high. It suggests that the pedestrian network should be built and vitalized at the local urban level. The second aspect is "Definition." The public pedestrian passage lacks a social, cultural, and legal definition and only has a passive physical definition. It suggests that a legal definition and specialized guildline be prepared. The third aspect is "Design": 1)Insufficient territoriality exists between the public pedestrian passage and the inside of the complex. Territoriality should be reinforced between the public pedestrian passage and the rest of the internal territory. 2)The landscaping adjacent to the public pedestrian passage lacks deliberation. Since this is where safety and privacy collide, detailed design and maintenance of the landscaping is required. 3)It lacks systematical crime prevention facilities and should compensate accordingly.