• Journal of the Korea Society of Computer and Information
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• v.13 no.5
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• pp.229-236
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• 2008

In this paper, re proposed scheme that it safely exchange encrypted keys without Trust Third Party(TTP) and Pre-distributing keys in ubiquitous environments. Existing paper assume that exist a TTP or already pre-distributed encrypted keys between nodes. However, there methods are not sufficient for wireless environments without infrastructure. Some existing paper try to use the Diffie-Hellman algorithm for the problem, but it is vulnerable to Replay and Man-in-the middle attack from the malicious nodes. Therefore, Authentication problem between nodes is solved by modified the Diffie-Hellman algorithm using ${\mu}TESLA$. We propose safe, lightweight, and robust pair-wise agreement algorithm adding. One Time Password(OTP) using timestamp to modified the Diffie-Hellman in ubiquitous environments, and verify a safety about proposed algorithm.

• Journal of the Korea Society of Computer and Information
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• v.19 no.11
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• pp.43-52
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• 2014

In this paper, we propose the target detection method using image displacement, and classification method using SURF(Speeded Up Robust Features) feature points and BAS(Beam Angle Statistics) in infrared images. The SURF method that is a typical correspondence matching method in the area of image processing has been widely used, because it is significantly faster than the SIFT(Scale Invariant Feature Transform) method, and produces a similar performance. In addition, in most SURF based object recognition method, it consists of feature point extraction and matching process. In proposed method, it detects the target area using the displacement, and target classification is performed by using the geometry of SURF feature points. The proposed method was applied to the unmanned target detection/recognition system. The experimental results in virtual images and real images, we have approximately 73~85% of the classification performance.

• Journal of the Korea Society of Computer and Information
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• v.25 no.6
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• pp.49-56
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• 2020

The virtual Korean keyboard system is a method of inputting characters by touching a fixed position. This system is very inconvenient for people who have difficulty moving their fingers. To alleviate this problem, this paper proposes an efficient framework that enables keyboard input and handwriting through video and user motion obtained through the RGB camera of the mobile device. To develop this system, we use face recognition to calculate control coordinates from the input video, and develop an interface that can input and combine Hangul using this coordinate value. The control position calculated based on face recognition acts as a pointer to select and transfer the letters on the keyboard, and finally combines the transmitted letters to integrate them to perform the Hangul keyboard function. The result of this paper is an efficient writing system that utilizes face recognition technology, and using this system is expected to improve the communication and special education environment for people with physical disabilities as well as the general public.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.1
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• pp.1-6
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• 2011

To improve fire-resistance of a high strength concrete against explosive spalling under elevated temperature, fibers can be mixed with concrete to provide flow paths of evaporated water within concrete to the free surface. The fiber-mix concrete approach is effective against explosive spalling when the flow path generated from melting fibers at the elevated temperature is interconnected to transport high pressurized evaporated water from the inside concrete to the free surface. The percolation theory can identify the connectivity of the fibers and provide an estimate of the fire-resistance of concrete by investigating layout of fibers. In this study, the correlation between percolation theory and explosive spalling of fiber-mixed high strength concrete is analyzed and the connectivity of the fiber in concrete is stereologically investigated by using virtual specimens of fiber-mixed high strength concrete.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.165-174
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• 2011

The purpose of this research is to develop the model for analyzing the hydraulic behavior of off-stream reservoir whose purpose is to reduce a peak flood. When a flood occurs in river, off-stream reservoir has a capability of sharing a part of peak flood. It is accomplished by flowing over a off-line weir that is built by lowering a portion of bank and connecting river with off-line reservoir. Since flood control depends on river elevation, characteristics of off-line weir (elevation, length, position et al.) and reservoir capacities, an integrated model linking the one dimensional unsteady river flow model, off-line weir model and two dimensional unsteady flood model is developed to analyze the behavior of off-stream reservoir and off-line weir. The results show that a flood control capability of off-stream reservoir strongly depends on facilities of off-line weir and storage capacity of offstream reservoir.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.191-200
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• 2011

Levee failure cause the huge amount of damage to human and property. Overflow and erosion of levee are primary cause of a break in a levee but the analysis of breach pattern and impact is partially inadequate. The flow characteristics of meandering rivers are very important in field of river hydraulics that should be studied in practical viewpoints relating to river levee. In meandering the secondary flow that rotary direction is changed reciprocally occurs in three dimension is known. In this study flow characteristics of local river are considered and of meandering channels are analyzed using CCHE2D and FLOW3D. The stability and accuracy of models are examined comparing the measuring and analyzed data for the experimental channel and natural river(Namgang). Consequently, the flow characteristics in a meandering river are suggested precisely and it is essential that river levees having meandering river should be analyzed.

• Fashion & Textile Research Journal
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• v.23 no.4
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• pp.504-514
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• 2021

This study attempted to extract and structure the job skills required for 3D designers, which have been recently introduced to the fashion industry. The study aimed to materialize and objectify the 3D designer's job, using a focus group interview for the survey. The 3D designer has the TD task of making 3D virtual samples using the pattern files developed in Pattern CAD. Graphic design and fabric digitization are also major tasks for the 3D designer. CLO is mainly used for 3D virtual sample production, and PixPlant, Substance, Photoshop, Cinema 4D, Daz studio, and 3ds MAX are used for image and avatar editing. As per the job skills required for 3D design work, basic knowledge about patterns and sewing, skill in 3D virtual clothing technology, ability to use various software, and English skills were considered important, in that order. In particular, the need for knowledge about patterns and sewing became more important than the skill in 3D virtual clothing technology itself. To train 3D designers, it was found that not only 3D virtual clothing software, but also education on patterns and clothing construction, CAD developer's curriculum certification system, and 3D designer qualification management were required. In addition, 3D designers are recognized as an essential job in fashion vendors, and the demand for domestic brands is increasing. The biggest limitation of the 3D virtual clothing system is the perfection of the digital fabric. Also, technical improvement is needed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.71-77
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• 2021

Recently, there is a demand for efficient program development of an IoT application support frameworks considering heterogeneous hardware characteristics. In addition, the scope of hardware support is expanding with the development of neuromorphic architecture that mimics the human brain to learn on their own and enables autonomous computing. However, most existing IoT IDE(Integrated Development Environment), it is difficult to support AI(Artificial Intelligence) or to support services combined with various hardware such as neuromorphic architectures. In this paper, we design an AI component abstract model that supports the second-generation ANN(Artificial Neural Network) and the third-generation SNN(Spiking Neural Network), and implemented an autonomous IoT IDE based on the proposed model. IoT developers can automatically create AI components through the proposed technique without knowledge of AI and SNN. The proposed technique is flexible in code conversion according to runtime, so development productivity is high. Through experimentation of the proposed method, it was confirmed that the conversion delay time due to the VCL(Virtual Component Layer) may occur, but the difference is not significant.

• Journal of the Korea Convergence Society
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• v.12 no.10
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• pp.1-8
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• 2021

In online meetings and classes using webcams, the chromakey technique is a very necessary part to produce content. We proposed a technology that enables background synthesis without using a cloth for chromakey. The proposed method consists of three steps: an HSI image conversion step, a step of detecting a region changed from a background, and a step of replacing the background region with a chromakey and applying it. In the input video, the block average image of each frame is calculated, and the difference between the block average image of the background image and the block average image of the input image is used to detect the change area. The developed chromakey effect technology uses a technique of acquiring a background image without an object from a single camera and extracting only an object by distinguishing the moving object and the background. The proposed method is not only capable of processing even if the background has a variety of colors, but also has the seamless processing of the boundary lines of objects.

• Journal of the Korea Society of Computer and Information
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• v.26 no.10
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• pp.61-76
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• 2021

Nowadays, a lot of educational TV programs have focused on the program providers' perspective, namely through goods-dominant (G-D) logic. However, the growing development of current technologies such as IPTV with AR and VR has opened opportunities to go beyond a provider-centered perspective and to add the co-creation of value, since value can be created through the interaction between learners and the TV programs themselves. With this in mind, learner-centered TV programs, which are based on service-dominant (S-D) logic, should be offered through educational TV channels. This conceptual paper summarizes, analyzes, and synthesizes the present status of IPTV in education and suggests a new instructional approach for utilizing TV in future education based on value co-creation through learner participation. Three principles (service-dominant logic as an educational service design principle, goal-based scenario for instructional design, IPTV as state-of-the-art technology innovation) are suggested for designing educational IPTV programs.