• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.39 no.6
• /
• pp.401-408
• /
• 2021

With the proposal of amendments to the Pedestrian Safety Act in 2021, when the amendment bill is passed in the near future, a general dimensional investigation of the sidewalks' physical condition, which is the basis of pedestrian safety, is expected to be legislated and made mandatory. Therefore, this study presented a affordable methodology for street environment survey using entry-level drones and examined the feasibility of conducting a complete survey of pedestrian paths by local governments nationwide. To this end, various street facilities in the experimental site were measured to compare and analyze the accuracy of the point cloud data. As a result of the analysis, it was found that the measurement error range satisfies the public surveying guidelines. If the methodology presented in this study is applied, it is expected that individual local governments will be able to make a significant contribution to monitoring the physical conditions of streets to improve the pedestrian environment in the near future.

• Journal of the Korea Society of Computer and Information
• /
• v.28 no.3
• /
• pp.1-9
• /
• 2023

In this paper, we identify the factors that hinder the application of quantum computing technology to solve meaningful real-world problems, and suggest related research trends and directions. To this end, we summarize the basic knowledge of quantum mechanics from the perspective of computer science, which is necessary to understand the difficulties in applying quantum computing technology, and analyze the currently commercialized quantum computers and quantum programming layers from the literature. Through an analysis of the current status and utilization of cloud-based commercial quantum computing services, we identify four factors that currently hinder the practical application of quantum computing: high barriers to entry for quantum computer programming, constraints on noisy intermediate-scale quantum computers, a still-growing open source ecosystem, and difficulties in simulating realistic problem sizes, and suggest trends and directions for related research. In doing so, it is expected to contribute to laying the groundwork for practical applications of quantum computing technology.

• Journal of the Korea Society of Computer and Information
• /
• v.28 no.2
• /
• pp.99-110
• /
• 2023

In this paper, we propose a system termed ForestLi that can accurately estimate the diameter at breast height (DBH) and tree height using LiDAR point cloud data. The ForestLi system processes LiDAR point cloud data through the following steps: downsampling, outlier removal, ground segmentation, ground height normalization, stem extraction, individual tree segmentation, and DBH and tree height measurement. A commercial system, such as LiDAR360, for processing LiDAR point cloud data requires the user to directly correct errors in lower vegetation and individual tree segmentation. In contrast, the ForestLi system can automatically remove LiDAR point cloud data that correspond to lower vegetation in order to improve the accuracy of estimating DBH and tree height. This enables the ForestLi system to reduce the total processing time as well as enhance the accuracy of accuracy of measuring DBH and tree height compared to the LiDAR360 system. We performed an empirical study to confirm that the ForestLi system outperforms the LiDAR360 system in terms of the total processing time and accuracy of measuring DBH and tree height.

• Journal of Korea Society of Industrial Information Systems
• /
• v.27 no.6
• /
• pp.69-75
• /
• 2022

We propose energy-efficient scheduling considering real-time constraints and energy efficiency in smart mobile with heterogeneous multi-core structure. Recently, high-performance applications such as VR, AR, and 3D game require real-time and high-level processings. The big.LITTLE architecture is applied to smart mobiles devices for high performance and high energy efficiency. However, there is a problem that the energy saving effect is reduced because LITTLE cores are not properly utilized. This paper proposes a heterogeneous multi-core assignment technique that improves real-time performance and high energy efficiency with big.LITTLE architecture. Our proposed method optimizes the energy consumption and the execution time by predicting the actual task execution time using SVM (Support Vector Machine). Experiments on an off-the-shelf smartphone show that the proposed method reduces energy consumption while ensuring the similar execution time to legacy schemes.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.2
• /
• pp.135-144
• /
• 2022

Electromagnetic topology (EMT) technique is a method to analyze each component of the electromagnetic propagation environment and combine them in the form of a network in order to effectively model the complex propagation environment. In a typical commercial communication channel model, since the propagation environment is complex and difficult to predict, a probabilistic propagation channel model that utilizes an average solution, although with low accuracy, is used. However, modeling techniques using EMT technique are considered for application of propagation and coupling analysis of threat electromagnetic waves such as electromagnetic pulses, radio wave models used in electronic warfare, local communication channel models used in 5G and 6G communications that require relatively high accuracy electromagnetic wave propagation characteristics. This paper describes the effective implementation method, algorithm, and program implementation of the electromagnetic topology (EMT) method analyzed in the frequency domain. Also, a method of deriving a response in the time domain to an arbitrary applied signal source with respect to the EMT analysis result in the frequency domain will be discussed.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.15 no.4
• /
• pp.249-256
• /
• 2022

In the case of Drone Photogrammetry, the "pixel to point tool" module of Metashape, Pix4D Mapper, ContextCapture, and Global MapperGIS, which is a simple software, are widely used. Each SW has its own logic for the analysis of aerial triangulation, but from the user's point of view, it is necessary to select a SW by comparative analysis of the coordinate values of geospatial information for the result. Taking aerial photos for drone photogrammetry, surveying GCP reference points through VRS-GPS Survey, processing the acquired basic data using each SW to construct ortho image and DSM, and GCPSurvey performance and acquisition from each SW The coordinates (X,Y) of the center point of the GCP target on the Ortho-Image and the height value (EL) of the GCP point by DSM were compared. According to the "Public Surveying Work Regulations", the results of each SW are all within the margin of error. It turned out that there is no problem with the regulations no matter which SW is included within the scope.

• Journal of Internet Computing and Services
• /
• v.24 no.2
• /
• pp.27-36
• /
• 2023

Waveguides are transmission lines that guide electromagnetic waves in the desired direction and are utilized in various fields such as medical devices, radar systems, and satellite communications. Computational electromagnetics (CEM) is essential for designing and optimizing waveguides. The finite element method (FEM), which is one of the numerical analysis techniques, is efficient in solving closed problems such as waveguides. In order to apply FEM for waveguide analysis, boundary conditions that truncate the computational domain are required. This paper performs electromagnetic simulations using absorbing boundary conditions (ABC) and waveguide port boundary conditions (WPBC) in 2/D and 3/D waveguides using the finite element method and compared their performances. The accuracy of the analysis was verified by comparing the results with HFSS, a representative commercial electromagnetic simulation software. Simulation results confirm that applying WPBC allows for smaller analysis domains than ABC.

• Membrane Journal
• /
• v.32 no.1
• /
• pp.57-65
• /
• 2022

Recently, computer simulation research has been rapidly increasing due to the development of computer and software technology. In particular, various computational simulation results related to polymers, which were previously limited by problems of the number of atoms and model size, are being published. In this study, a study was conducted to analyze the mechanical properties, one of the important properties for using a polymer material as a membrane, using molecular dynamics (MD) simulation. To this end, polyethylene (PE) and polystyrene (PS), which are commercial polymer materials with widely reported related properties, were selected as polymer models and the tensile properties of each polymer were compared through the difference in main chain length. Through the density, radius of gyration, and scattering analysis, it was found that the model produced in this study was in good agreement with the mechanical property trends obtained in the actual experiment. It is expected to enable the prediction of mechanical properties of various polymer materials for membrane fabrication.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.5 no.2
• /
• pp.207-214
• /
• 2015

Stress concentrations around discontinuities, such as a hole or a sudden change in cross section of a structural member, have great important cause in the most materials failure because the stress near the points of application of concentrated loads can reach values much larger than the average value of the stress in the member. This paper presents the stress concentrations between fillet and hole at different locations in a stepped plate under tensile loading. The analysis for interaction effect of stress concentration was performed by photoelasticity and ANSYS which is a commercial finite element software. From the analysis results, the circular hole located at the different position from the fillet radius can cause different values of stress concentration factor within interacting region.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.18 no.2
• /
• pp.61-88
• /
• 2007

The purpose of this study is to provide an actual basic data and helps for arranging the next generation OPAC's interface and function through improving the existing OPAC's interface and improvement in the domestic library. In this study, factors to be importantly considered for improving the OPAC's interface and function were examined based on the preceding studies on OPAC concept & development process, user's library use style, user use style of OPAC, and recognition on library's crisis, and actual condition investigation result. Also, the case analysis on the existing OPAC's interface and function was focused on the search window, search item, search method, alignment function, search result display and search result feedback. Also, the search interface and search function of the next generation OPAC which is provided by the recently-developed domestic and foreign library utilization, and the detailed case were analyzed in the aspect of Library 2.0 service. Finally, the measures for improving the existing OPAC's interface and function in domestic library were suggested.