• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.1-9
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• 2008

Thanks to the multimedia technology development, it is possible to show image representations in high quality and to process images in various ways. Anisotropic diffusion as an effective diffusion filtering among many image preprocessing methods and postprocessing methods is used in reduction of speckle noises of ultrasound images, image restoration, edge detection, and image segmentation. However, the conventional anisotropic diffusion based on a cross-kernel causes the following problems. The problem is the concentration of edges in the vertical or horizontal directions. In this paper, a new anisotropic diffusion transform based on directions of gradient is proposed. The proposed method uses the eight directional square-kernel which is an expanded form of the cross-kernel. The proposed method is to select directions of small gradient based on square-kernel. Therefore, the range of proposed diffusion is selected adaptively according to the number of the directions of gradient. Experimental results show that the proposed method can decrease the concentration of edges in the vertical or horizontal directions, remove impulse noise. The image in high quality can be obtained as a result of the proposed method.

• Proceedings of the Korean Society for the Gifted Conference
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• 2003.05a
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• pp.143-144
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• 2003

6차 교육과정부터는 과학 교육에서 학생들의 학습 목표를 과학 개념에 대한 이해 뿐 아니라 탐구 사고력 및 기능 향상도 중요한 목표로서 취급하고 있다(교육부, 1992). 그런데 학생의 탐구 사고력을 향상시킬 수 있는 과학교육이 제대로 이루어지지 못하고 있는 것이 현재의 실정이다. Schwab(1961)가 탐구 학습의 단계를 분류하면서 지적한 바 있듯이 탐구는 주어진 과제를 해결하는 고정적 탐구보다는 스스로 과제를 설정하고 이를 해결하려 하는 유동적 탐구가 더 바람직한 방향이며, 이러한 유형의 탐구를 통하여 학생들은 창의성의 신장과 함께 과학적탐구가 이루어지는 과정을 더 올바르게 이해할 수 있을 것으로 생각된다. 따라서 탐구의 상황을 학교 실험실만이 아닌 좀 더 생활 주변의 여러 가지 경험과 관련된 쪽으로 안내하는 것도 필요하다. 최근 활발한 컴퓨터의 보급과 인터넷 환경의 확대로 인하여 학생들이 이러한 환경에서 교사와 직접 동일한 시간, 동일한 장소에서 대면하지 않고도 의사소통하고 교수-학습이 이루어질 수 있는 기회가 사회적으로 가능해지고 있다. 이러한 원격교육은 교사의 안내에 따른 탐구 교수 형태의 개념 확인 및 검증 실험이 대부분인 전통적 과학학습 방법과 달리 학생 스스로 문제를 찾고 해결하려고 시도하는 것을 통하여 과학적 탐구 기능의 향상은 물론 과학적 개념의 획득, 과학, 사회, 기술에 대한 폭넓은 인식을 형성하는데 도움이 된다. 또한 인터넷 환경을 이용하면 학교 실험실 상황을 벗어나 학생들에게 다양한 탐구 활동 기회를 제공할 수 있고, 또한 그에 따른 의사 소통이 더 용이해질 수 있다. 이에 따라서 본 연구에서는 탐구 과정기술과 사고력을 중시하는 초등학교 과학과목의 특성을 고려하여 이에 적합한 인터넷 원격교수-학습을 위한 교수-학습 모형과 학생들의 과학적 탐구력과 사고력을 신장시킬 수 있는 멀티미디어 학습자료를 개발하고, 이를 실제적으로 적용할 수 있는 웹사이트를 개발, 현장에 적용하여 원격교수학습이 과학적 탐구력과 사고력에 미치는 효과에 대하여 조사하였다.

• Journal of Broadcast Engineering
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• v.7 no.1
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• pp.21-27
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• 2002

This paper presents a mews event reenactment system (NERS), which generates virtual character animations in a quick and convenient manner. Thus, NERS can be used to produce computer graphics(CG) scenes of news events that are hard to photograph, such as fire, traffic accident, cases of murder, and so on. By using plenty of captured motion data and CG model data this system produces an appropriate animation of virtual characters straightforwardly without any motion capturing device and actors in the authoring stage. NERS is designed to be capable of making virtual characters move along user-defined paths, stitching motions smoothly and modifyingthe positions and of the articulations of a virtual character in a specific frame. Therefore a virtual character can be controlled precisely so as to interact with the virtual environments and other characters. NERS provides both an interactive and script-based (MEL: Maya Embedded Language) interface so that user can this system in a convenient way. This system has been implemented as a plug-in of commercial CG tool, Maya (Alias/wavefront), in order to make use of its advanced functions

• Journal of Broadcast Engineering
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• v.8 no.1
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• pp.19-29
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• 2003

The demand for high-resolution images is gradually increasing, whereas many imaging systems yield aliased and undersampled images during image acquisition. In this paper, we propose a high-resolution image reconstruction algorithm considering inaccurate subpixel registration. A regularized Iterative reconstruction algorithm is adopted to overcome the ill-posedness problem resulting from inaccurate subpixel registration. In particular, we use multichannel image reconstruction algorithms suitable for application with multiframe environments. Since the registration error in each low-resolution has a different pattern, the regularization parameters are determined adaptively for each channel. We propose a methods for estimating the regularization parameter automatically. The preposed algorithm are robust against the registration error noise. and they do not require any prior information about the original image or the registration error process. Experimental results indicate that the proposed algorithms outperform conventional approaches in terms of both objective measurements and visual evaluation.

• Archives of design research
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• v.16 no.1
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• pp.219-228
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• 2003

Nowadays, the progress of high technology in modern society provides humankind with the opportunity to obtain diverse information easily and quickly. Among those rapidly progressing fields of high technology, digital media field has the ability to substitute for the multimedia information society by being applied to many related fields and daily life. Specifically, the concern and enthusiasm for the restoration of cultural property has risen. So, effective methods are required to decide on the preservation, restoration and academic value of cultural property. Among these, image processing technology using computers has been introduced. The restoration of cultural property using this technique has been studied vigorously in many advanced countries because this would allow us to restore damaged parts without destroying the original asset. However, in Korea, though we have numerous examples of cultural property with recorded history, research related to the items has scarcely been conducted. Accordingly, this study focuses on the investigation of virtual reality and the techniques applicable to restoring cultural property in addition to suggesting the significance and possibility of digitally restoring cultural property following the introduction of applicable examples both domestically and abroad.

• Journal of Broadcast Engineering
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• v.21 no.2
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• pp.252-260
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• 2016

The performance of human detection system is affected by camera location and view angle. In 2D image acquired from such camera settings, humans are displayed in different sizes. Detecting all the humans with diverse sizes poses a difficulty in realizing a real-time system. However, if the size of a human in an image can be predicted, the processing time of human detection would be greatly reduced. In this paper, we propose a method that estimates human size by constructing an indoor scene in 3D space. Since the human has constant size everywhere in 3D space, it is possible to estimate accurate human size in 2D image by projecting 3D human into the image space. Experimental results validate that a human size can be predicted from the proposed method and that machine-learning based detection methods can yield the reduction of the processing time.

• Korean journal of communication and information
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• v.66
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• pp.159-183
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• 2014

This study analyzed the competition among three game platforms, PC, Console and Mobile in aspect of user's gratifications using niche analysis. To do this, four gratification factors, 'transportability and accessibility', 'liveliness and variety', 'availability and economic feasibility', 'relationship', were assessed. To investigate competition level among three game platforms, niche breadth, niche overlap, competitive superiority of four gratification factors were analyzed. The results of niche analysis show that mobile platform appeared as a most competitive platform because it utilized diverse resources for game user gratification and had competitive superiority in 'transportability and accessibility' which appeared as most important factor determining user's gratification. However there was no game platform which had competitive superiority in all four gratification factors.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.3
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• pp.397-403
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• 2020

With the convenience of real-time conversation, multimedia file and contact sharing services, most people use instant messenger, and its usage time is increasing. Because the messengers contain a lot of user behavior information data, in the digital forensic investigation, they can be very useful evidence to identify user behavior. However, some of useful data can be difficult to acquire or recognize because they are encrypted or deleted. Thus, in order to use the messenger data as evidence, the study of message decryption process and message recovery is essential. In this paper, we analyze the database encryption process of the instant messenger, MalangMalang Talkafe, and propose the method to decrypt it. In addition, we propose the methods to identify the deleted messages and recover from the volatile memory area.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.7
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• pp.1575-1581
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• 2003

As a society has progressed rapidly toward a highly advanced digital information age, a multimedia communication service for acquisition, transmission and storage of image data as well as voice has being commercialized externally and internally. However, in the process of digitalization or transmission of data, noise is generated by several causes, and researches for eliminating those noises have been continued until now. There were the existing FFT(fast fourier transform) and STFT(short time fourier transform) for removing noise but it's impossible to know information about time and time-frequency localization capabilities has conflictive relationship. Therefore, for overcoming these limits, wavelet transform which is presented as a new technique of signal processing field is being applied in many fields recently. Because it has time-frequency localization capabilities it's Possible for multiresolution analysis as well as easy to analyze various signal. And when two wavelet base were designed to form Hilbert transform pair, wavelet pair provide superior performance than the existing DWT(discrete wavelet transform) in data characteristic detection. Therefore in this parer, we removed impulse noise by using adaptive-length median filter and two dyadic wavelet base which is designed by truncated coefficient vector.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.5
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• pp.1060-1065
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• 2011

In this paper, the proposed method is recognized the hands using color information with input image of the camera. It controls the mouse pointer using recognized hands. In addition, specific commands with the mouse pointer is designed to perform. Most users felt uncomfortable since existing interaction multimedia systems depend on a particular external input devices such as pens and mouse However, the proposed method is to compensate for these shortcomings by hand without the external input devices. In experimental methods, hand areas and backgrounds are separated using color information obtaining image from camera. And coordinates of the mouse pointer is determined using coordinates of the center of a separate hand. The mouse pointer is located in pre-filled area using these coordinates, and the robot will move and execute with the command. In experimental results, the recognition of the proposed method is more accurate but is still sensitive to the change of color of light.