• Journal of the Earthquake Engineering Society of Korea
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• v.27 no.4
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• pp.163-170
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• 2023

In the fluid-structure interaction analysis, the finite element formulation is performed for the wave equation for dynamic fluid pressure, and the dynamic pressure is defined as a degree of freedom at the fluid nodes. Therefore, to connect the fluid to the structure, it is necessary to connect the degree of freedom of fluid dynamic pressure and the degree of freedom of structure displacement through an interface element derived from the relationship between dynamic pressure and displacement. The previously proposed fluid-structure interface elements use conformal finite element meshes in which the fluid and structure match. However, it is challenging to construct conformal meshes when complex models, such as water purification plants and wastewater treatment facilities, are models. Therefore, to increase modeling convenience, a method is required to model the fluid and structure domains by independent finite element meshes and then connect them. In this study, two fluid-structure interface elements, one based on constraints and the other based on the integration of nonsmooth functions, are proposed in nonconformal finite element meshes for structures and fluids, and their accuracy is verified.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2D
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• pp.259-267
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• 2008

Nowadays PMIS (Project Management Information System) based on web is widely applied to communication, collaboration and community in construction jobsite for various organization such as subcontractors, general contractor, engineering company, supervisors and client. However, individual PMIS in jobsite is prone to be troublesome issue for integration and exchange of information regarding project management in corporate and may result in conflict of data application. The main reason should be lack of information strategy plan such as company master plan for information. This research shows a critical success factor that a big construction company of Korea establishes procedure and method for information strategy plan. In addition, It is to suggest how to be implemented PMIS architecture and execute business process innovation in corporate level. This research expects contribution that many construction companies reduce mistakes to be implemented management information system and to optimize system in corporate level.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.329-329
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• 2022

Accurate characterization of terrestrial precipitation variation from high spatial resolution satellite sensors is beneficial for urban hydrology and microscale agriculture modeling, as well as natural disasters (e.g., urban flooding) early warning. However, the widely-used top-down approach for precipitation retrieval from microwave satellites is limited in several hydrological and agricultural applications due to their coarse spatial resolution. In this research, we aim to apply a novel bottom-up method, the parameterized SM2RAIN, where precipitation can be estimated from soil moisture signals based on an inversion of water balance model, to generate high spatial resolution terrestrial precipitation estimates at 0.01º grid (roughly 1-km) from the C-band SAR Sentinel-1. This product was then tested against a common reanalysis-based precipitation data and a domestic rain gauge network from the Korean Meteorological Administration (KMA) over central South Korea, since a clear difference between climatic types (coasts and mainlands) and land covers (croplands and mixed forests) was reported in this area. The results showed that seasonal precipitation variability strongly affected the SM2RAIN performances, and the product derived from separated parameters (rainy and non-rainy seasons) outperformed that estimated considering the entire year. In addition, the product retrieved over the mainland mixed forest region showed slightly superior performance compared to that over the coastal cropland region, suggesting that the 6-day time resolution of S1 data is suitable for capturing the stable precipitation pattern in mainland mixed forests rather than the highly variable precipitation pattern in coastal croplands. Future studies suggest comparing this product to the traditional top-down products, as well as evaluating their integration for enhancing high spatial resolution precipitation over entire South Korea.

• Korean Journal of Social Welfare Studies
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• v.42 no.2
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• pp.235-274
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• 2011

The purpose of this study is to understand suffering of torture for victims with suspicion of espionage under the military government in Korea by knowing meaning and structure of empirical phenomena. Methods is to applied to Phenomenological and heuristic Human Becoming Methodology, and the subjects of this study are text for three tortured victims. Results is the structure that the victims accepted their act of espionage under the torture and horror, living with retribution from heaven, surviving pressured times, and fighting for human rights upon release from prison. The conceptual integration of relationship issues were: valuing, imaging, languaging with powering and transforming under the process of revealing-concealing and enabling-limiting. Finally, discussion and practical meaning was reviewed.

• Journal of The Geomorphological Association of Korea
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• v.27 no.2
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• pp.1-17
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• 2020

This study evaluated a debris landform distribution potential area map in the southwest region of the Korean peninsula. A GIS spatial integration technique and logistic regression method were used to produce a distribution potential area map. Seven topographic and environmental factors were considered for analysis and 28 different data set were combined and used to get most effective results. Moreover, in an accuracy assessment, the extracted results of the Distribution Potential area were evaluated by conducting a cross-validation module. Block stream showed the highest accuracy in the combination No. 6, and that DEM (digital elevation model) and TWI (topographic wetness index) have relatively high influences on the production of the Block stream Distribution Potential area map. Talus showed the highest accuracy in the combination No. 13. We also found that slope, TWI and geology have relatively high influences on the production of the Talus Distribution Potential area map. In addition, fieldwork confirmed the accuracy of the input data that were used in this study, and the slope and geology were also similar. It was also determined that these input data were relatively accurate. In the case of angularity, the block stream was composed of sub-rounded and sub-angular systems and Talus showed differences according to the terrain formation. Although the results of the rebound strain measurement using a Schmidt's hammer did not shown any difference in topographic conditions, it is determined that the rebound strain results reflected the underlying geological setting.

• Journal of Practical Engineering Education
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• v.15 no.3
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• pp.739-750
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• 2023

Several preceding studies have been conducted to integrate the education programs and qualification examination systems in higher education institutions, such as four-year engineering colleges and vocational universities. However, in practice, the implementation of such integration is a rare occurrence. The most ideal method of integrating education and qualifications can be seen as the unified operation of educational programs and qualification assessments. However, various elements required for accreditation of educational institutions and qualification systems must precede this. In this paper, we first compare and analyze the currently implemented competency-based qualification system and the Accreditation for engineering education evaluation operating as a quality management system for educational programs. Subsequently, through a case study of University K, which concurrently operates the Accreditation for engineering education and competency-based qualification systems, we examine the potential linkage between education and qualifications. After reviewing the case that education and qualifications can be linked, and reflecting the analysis results, if a program that has obtained the Accreditation for engineering education operates a curriculum that satisfies the criteria for Course-based Qualification System. We propose Accreditation-based Qualification System that can grant qualifications, students who have completed it will be provided.

• Land and Housing Review
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• v.14 no.4
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• pp.95-102
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• 2023

Numerous investigations have explored the integration of machine leaning algorithms with high-resolution drone image for object detection in urban settings. However, a prevalent limitation in vehicle extraction studies involves the reliance on bounding boxes rather than instance segmentation. This limitation hinders the precise determination of vehicle direction and exact boundaries. Instance segmentation, while providing detailed object boundaries, necessitates labour intensive labelling for individual objects, prompting the need for research on automating unsupervised instance segmentation in vehicle extraction. In this study, a novel approach was proposed for vehicle extraction utilizing unsupervised SVM classification applied to vehicle bounding boxes in drone images. The method aims to address the challenges associated with bounding box-based approaches and provide a more accurate representation of vehicle boundaries. The study showed promising results, demonstrating an 89% accuracy in vehicle extraction. Notably, the proposed technique proved effective even when dealing with significant variations in spectral characteristics within the vehicles. This research contributes to advancing the field by offering a viable solution for automatic and unsupervised instance segmentation in the context of vehicle extraction from image.

• Journal of Aerospace System Engineering
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• v.17 no.6
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• pp.108-117
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• 2023

Thus far, a mission software component of the KT-1 military fixed-wing aircraft for overseas export has been developed through international joint development with foreign companies. The reliability of the software component could be certified by complying with the development environment and procedures of foreign companies based on DO-178B. However, recently, DO-178C certification is required for overseas exports, and reliability tests to comply with the weapon system software development guidelines are required for domestic military forces. In this paper, we describe the problems in obtaining domestic airworthiness certification in the international joint development of a previously developed KT-1 export-typed aircraft system integration project. To this end, we find a solution to comply with both DO-178C and the Weapon System Software Development and Management Manual and provide the optimal software reliability test method.

• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.105-114
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• 2023

In this paper, we propose a deployment and operation scheme of UxNB network toward mobile IAB. By operating a UxNB network based on SDN(Software Defined Network), UxNBs are deployed in areas where mobile communication services are desired. After deploying UxNB in the service area, IAB can be set up to perform mobile communication services. For this purpose, this paper first proposes a UxNB Network Controller consisting of a UAV Controller and an SDN Controller, and proposes the necessary functions. Next, we present a scenario in which a UxNB network can be deployed and operated in detail step by step. We also discuss the location of the UxNB network controller, how to deliver control commands from the UAV controller to the UxNB, how to apply IAB for UxNB networks, optimization of UxNB networks, RLF(radio link failure) recovery in UxNB networks, and future research on security in UxNB networks. It is expected that the proposed UxNB Network Controller architecture and UxNB network deployment and operation will enable seamless integration of UxNB networks into Mobile IAB.

• Journal of Cadastre & Land InformatiX
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• v.53 no.2
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• pp.39-52
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• 2023

Cadastral maps are important official documents that affect property rights and have experienced issues due to over 100 years of usage. The accuracy of these old cadastral maps has decreased due to damage, wear, and the accumulation of errors during the rewriting process. These errors have persisted into the digitalization process, creating difficulties in map management. A nationwide project to revise cadastral and forest maps is underway, but there are technical and legal challenges in making corrections. This study addresses the technical aspects of map maintenance and proposes a method to reduce errors and improve maintenance rates by preceding with boundary adjustments. The results show that by preceding with boundary adjustments, the average distance discrepancy decreases from 22.56cm to 8.12cm, and the maintenance rate increases by more than 10%.