• Journal of Korean Society of Coastal and Ocean Engineers
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• v.35 no.3
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• pp.49-56
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• 2023

The allowable mean overtopping discharge is used as a design parameter for coastal structures. The crest elevation of coastal structures should ensure the wave overtopping discharge within acceptable limits for structural safety and the safety of pedestrians, vehicles, operations, and so on. In this study, two-dimensional physical model tests on typical rubble-mound structure geometries were performed and the the mean wave overtopping discharges under various water depth and wave conditions were measrued. The various test conditions were applied to the tests with the change of the wave steepness, relative freeboard and relative wave height. An empirical formula from the experimental data was proposed to predict the mean wave overtopping volumes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.9-16
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• 2020

Wireless charging has been considered an essential part of recent mobile devices. Moreover, various wireless charging systems have emerged through many studies. Among the systems, in the 2D flat coil system, the transmitter coil and receiver coil are arranged horizontally as close as possible to improve the charging efficiency. Nowadays, the 3D coil system has been proposed by adding some slope to flat 2D coils to reduce the volume. On the other hand, the 3D coil system has a lower charging efficiency than the 2D system that decreases rapidly with increasing distance. This paper proposes a new system that improves the low efficiency and charging freedom, which are the drawbacks of the existing 3D systems. The proposed system was designed in three-dimensions, and another transmitter coil was added to the transmitter coil to improve the transmission efficiency and flexibility. The measurement showed that the charging efficiency of the proposed system was 40.10% when the distance between coils was 8 mm, which is 20.5 % improvement over the existing one. The proposed method can be applied when new wireless charging systems are designed and improve charging efficiency can be improved.

• Land and Housing Review
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• v.6 no.2
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• pp.67-77
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• 2015

Now that it is the current situation that the smooth supply and demand are necessary for 2nd phase of beginning construction and stable development of Gaesung Industrial Complex, this study was willing to offer the planning criteria and model to establish the lodging for the workers in Gaesung Industrial Complex based on the agreement that both South and North Korea agreed in 2007. Regarding the plan, its standard and the alternative were reviewed considering welfare of workers, economic efficiency, technical validity, possibility of agreement and long-term development. The exclusive area per capita was calculated through Labor Standards Act of Korea and status survey of lodging for the workers provided to border line area between China and North Korea and the economic alternative based on one room for 6 persons with the public restroom was compared with that of development type based on one room for 4 persons with indoor restroom. Especially regarding the proposed site, the area with the optimized position was set by considering gradient, accessibility and convenience of development out of the area of Dongchang-ri where was agreed already and the priority of the proposed site that can keep the existing building site and provide was offered. The necessary period for whole construction was set as approximately 36 months. Regarding construction method, RC Rahmen method was selected as the optimized alternative considering the workmanship of manpower of North Korea and conditions of supply and demand of materials and cluster-type vehicle allocation plan based on 4~6 units considering the efficiency of supplying service facilities and convenient facilities along the simultaneous accommodation of 15,000 people was offered. It was analyzed that total business expenses of approximately 80~100 billion Korean Won would required though there were the difference for each alternative in the charged rental way that the development business owner develops by lending the inter-Korea Cooperation Fund and withdraws the rent by the benefit principle. The possibility of withdrawing the rent was analyzed assuming that the period of withdrawing the investment is 30 years. Especially for the operation management after moving, the establishment of the committee of operating the lodging for the workers of Gaesung Industrial Complex (tentative name) was offered with the dualized governance that the constructor takes charge of operational management, collecting fees and management of infrastructure and human resource management is delegated to North Korea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.58-65
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• 2020

3D Models of offshore plant piping materials designed by 3D CAD systems are provided to the production processes in the form of 2D piping drawings and 2D piping installation drawings. In addition to the standard engineering information, the purchasing, procurement, manufacturing, installation, and inspection of raw materials are managed systematically in an integrated process control system. The existing integrated process management system can help reduce the processing time by managing the flow and progress of resources systematically, but it does not include 3D design model information. Hence, it is difficult to understand complicated pipe structures before installing the pipe. In addition, when design changes or immediate design modifications are required, it is difficult to find related data or exchange information quickly with each other. To solve this problem, an offshore plant-piping process-monitoring system was developed based on a 3D model. The 3D model-based piping monitoring system is based on Visual Studio 2017 C# and UNITY3D so that the piping-process work information can be linked to the 3D CAD model in real time. In addition, the 3D model could check the progress of the pipe installation process, such as block, size, and material, and the progress of functional inspection items, such as cleaning, hydraulic inspection, and pneumatic inspection.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.26-32
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• 2017

VOD (Video-On Demand) Services are considered to be one of the most successful data broadcasting services, along with Electronic Program Guides (EPGs). In particular, VOD services provide supplementary revenue for broadcasting companies in addition to the existing subscription fees and advertisement-based revenue. Therefore, each broadcasting company has developed its own VOD service and constantly seeks to improve it. This leads to the development of new VOD services, so developers are considering ways to effectively handle the frequent development needs. In this background, we conducted underlying research to apply the feature-oriented analysis model to the development of VOD services. The feature-oriented analysis model used in this study is the Feature-Oriented Domain Analysis (FODA) one developed by SEI of Carnegie Mellon University. FODA provides a tool for specifying the feature model of a software domain, based on which the developers can determine the configuration of the software with the customers. This study developed a feature model of the VOD service domain and devised the functionalities and test cases in an integrated manner with the feature model. Additionally, we proposed a VOD service development process utilizing the feature model, function specification, and test cases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3448-3454
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• 2014

Generally existing structure analysis was applied to elastic analysis basically in practice. Considering the nonlinear material and the nonlinear geometric to be a more precise analysis, for this reason, The necessity for a structual analysis have been constantly required. Therefore, after optimization is performed, designed a simple model which is applied the principle of nonlinear in this study, a structural analysis of existing experienced users, have a aims at presenting theory and a method in order to perform anyone the analysis easily. In this study, the proposed model applied to die ribs, Regarding the shear load, less strain and stress was generated but strength was sufficient. The initial strain and stress was reconfigured to fit the size and shape, A hyperstudy in conjunction with Abaqus with nonlinear structural analysis, revealed an acceptable maximum and minimum range of stress and under the conditions of minimum strain, the plate made with a constant increment. In the experimental models, the plate thickness was given a power of 40 Newton, according to the thickness of the press die through an iterative process. When the stress and strain was applied to the die thickness, 7-8mm thickness could be obtained by optimizing.

• Journal of Advanced Navigation Technology
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• v.15 no.6
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• pp.1000-1007
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• 2011

Home Networking will be implementing the interactive network by home appliances over wireless/wireline network framwork. That is, Home appliances, which are being operated within home space configure the network through wireline/wireless network infrastructure for interworking and interacitive services by external internet access. Based on home networking, smarthome is home space where can use automatic telecommunication and interactive service by home appliances. we can call smarthome based on home networking infrastructure as the conceptual gateway for evolving future converged space like u-city. From simple home control service to home automation service over home networking infrastructure, smarthome service is evolving to up-to-date intelligent life environment in growth of IT technology. however, its service model development was based on supplier-centered based on advanced IT technology. because of this situation, smarthome service has not been acknowledged IT underprivileged people as well as IT early-adaptor. so, this research paper will consider and try to find out what will be the feasible factors to make the best service for IT underprivileged people.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.129-136
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• 2020

A Cut Out Switch (COS) is used for line protection and pole transformer protection in power systems. The COS used to protect the pole transformer is installed on the power side of the pole transformer to protect the electric equipment from fault currents. The COS is composed largely of a body and a fuse holder, and when the fault current is energized, the element of the fuse link in the fuse holder is melted to block the fault current. The arc generated when the COS fuse link is blown causes fire and noise, causing discomfort to residents in the surrounding area, and the arc flame can cause secondary damage to the peripheral device. In this study, a current-limiting COS fuse with improved overcurrent blocking performance rather than explosion type was developed to solve the arc and noise problems during COS operation. The overcurrent breaking performance of the current-limiting COS improves the reliability by developing a striker and COS fuse bracket. In addition, this study aimed to verify the performance of the developed current-limiting COS fuse through a test at an authorized institution.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.583-598
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• 2022

As human-based tunnel inspections are affected by the subjective judgment of the inspector, making continuous history management difficult. There is a lot of deep learning-based automatic crack detection research recently. However, the large public crack datasets used in most studies differ significantly from those in tunnels. Also, additional work is required to build sophisticated crack labels in current tunnel evaluation. Therefore, we present a method to improve crack detection performance by inputting existing datasets into a deep learning model. We evaluate and compare the performance of deep learning models trained by combining existing tunnel datasets, high-quality tunnel datasets, and public crack datasets. As a result, DeepLabv3+ with Cross-Entropy loss function performed best when trained on both public datasets, patchwise classification, and oversampled tunnel datasets. In the future, we expect to contribute to establishing a plan to efficiently utilize the tunnel image acquisition system's data for deep learning model learning.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.325-330
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• 2021

This study set out to investigate the forms, attributes, and escape methods of post-subjects projected on the investigator's works in connection with rhizomatic thinking proposed as a way of social transformation by Deleuze and Guattari and examine their social connotations. Post-subjects projected on the investigator's works are not completed wholes of some sort, but like materials whose constant premise is change and creation. In the investigator's works, post-subjects have conscious and unconscious desire. It is the desire of creation with positive attributes including Deleuze's and Guattari's pursuit of changes in a contradicting society. When desire is deployed in post-subjects, they will carry out an escape. This way of escape is rhizomatic proposed by Deleuze and Guattari. It deconstructs contradicting things and repeats connection, contact, and severance with the outside world, building a new order. Rhizomatic post-subjects appearing in the investigator's works depict the escape process and method in abstract ways through the variable installation of objets combined with a color field of repeating brushes. In this work, the goal of post-subjects is to make a safe landing in a space where beings are recognized for their values and free and creative lives. These post-subjects are nomads creating a new landscape continuously, wandering around vast plains, and also artists and literary figures resisting a contradicting society. That is, they are connected to the concept of a war machine proposed by Deleuze and Guattari as a concept of social transformation and to the concept of Nietzsche's Agon to devise and create new values and politics based on street passion. They seek after a space where they can co-exist with otherness recognized rather than the complete deconstruction of the old order.