• Journal of Korea Multimedia Society
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• v.8 no.12
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• pp.1572-1580
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• 2005

The common requirements for watermarking are usually invisibility, robustness, and capacity. We proposed the watermarking for 3D mesh model based on projection onto convex sets for invisibility and robustness among requirements. As such, a 3D mesh model is projected alternatively onto two convex sets until it converge a point. The robustness convex set is designed to be able to embed watermark into the distance distribution of vertices. The invisibility convex set is designed for the watermark to be invisible based on the limit range of vertex movement. The watermark can be extracted using the decision values and index that the watermark was embedded with. Experimental results verify that the watermarked mesh model has both robustness against mesh simplification, cropping, affine transformations, and vertex randomization and invisibility.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.7
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• pp.1254-1259
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• 2007

Watermark insertion methods on low frequency subbands in wavelet transform image are robust in attacks, but become reduction of invisibility. And watermark insertion methods on high frequency subbands have a good visibility, but are weak in attack. In this paper, we propose the method that improve invisibility and robustness of watermarks according as we adaptively control insertion intensity by using subband characteristics and perceptual weights. Experimental result, we show that the proposed method has excellent of invisibility and robustness more than the conventional method, according as it is improved with $1.7dB{\sim}2.6dB$ in invisibility, and is improved with $0.2{\sim}12.9$ in similarity measurement.

• Journal of Broadcast Engineering
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• v.20 no.6
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• pp.888-900
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• 2015

This paper proposes a blind watermarking scheme using DWT satisfying robustness, invisibility, and security to protect the ownership of digital image contents. This scheme does not determine any watermarking position by local image information. It rather inserts the watermark information into all the four lowest frequency subbands after transforming the host image by n-level 2-dimensional DWT, depending on, the sizes of the host image and the watermark data. Its watermark insertion methodology uses some weighting factors according to the kind of the subband and its energy level to adjust the invisibility and the robustness of the watermark. This method is experimented for various pixel-value change attacks and geometric attacks with various images having different resolutions and aspect ratios. With the experimental results and by comparing with existing methods, we show that the proposed method has a great deal of general usage with good watermark invisibility and good robustness against attacks.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.103-105
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• 2009

This paper presents a pseudorandom tag arrangement for improved RFID based mobile robot localization. First, four repetitive tag arrangements, including square, parallelogram, tilted square, and equilateral triangle, are examined. For each tag arrangement, the difficulty in tag installation and the problem of tag invisibility are discussed. Then, taking into account both tag invisibility and tag installation, a pseudorandom tag arrangement is proposed, which is inspired from a Sudoku puzzle. It is shown that the proposed tag arrangement exhibits spatial randomness quite successively without increased difficulty in installation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1222-1228
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• 2006

In this paper, I propose a video watermaking method using adaptive threshold value and half-cell motion vector. Conventional method cause a lot of change of motion vectors and bring about a falling-off in invisibility, because it search embedding condition about whole macroblocks and watermarks are embedded in arbitrary motion vectors. Proposed method improve invisibility and decrease in number of change of motion vectors, because it create threshold value by using power of motion vector(PMV), and watermarks are embedded in motion vectors which greater than threshold value. Consequently, proposed method improve invisibility with on an average 5.4 dB ~9.3dB according to video bit-stream.

• Journal of the Korean Society of Costume
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• v.56 no.7 s.107
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• pp.101-114
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• 2006

The purpose of this study was to delve into the features of paradigm in conjunction with changing convergence culture in the 21st century's knowledge-based society, the influence of convergence paradigm on fashion, and changes in convergence culture. After identifying the features of the paradigm of knowledge-based society in association with changing convergence culture, the characteristics of fashion paradigm were examined in con=junction with the characteristics of the paradigm, and the convergence phenomena of modern fashion were investigated to figure out fashion trends. The findings of the study were as follows: According to the features of ubiquitous technology based on the theories of Mark Weiser and other futurologists, the characteristics of changing convergence culture in knowledge-based society could be classified into invisibility, relationship and materialized virtuality. When relevant theories were reviewed, invisibility, relationship and materialized virtuality are identified as the unique features of the paradigm of changing convergence culture in knowledge-based society. But those characteristics aren't separate concepts. Instead, they are being connected and fused together, thanks to universalized digital technology and ubiquitous technology. Changing convergence culture has brought a change to fashion paradigm as well. There is a type of design that lets all the characteristics stand out, and another design fuses just some of them together conceptually or formally. That is, fashion paradigm is marked by a combination of invisibility, relationship and an embodiment of virtual reality to be in line with changes in convergence culture.

• The Journal of Information Systems
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• v.16 no.4
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• pp.51-73
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• 2007

Ubiquitous computing is enhancing computer use by making many computers available throughout the physical environment, but making them effectively invisible to the user. To facilitate the successful adoption and diffusion of ubiquitous computing, it is necessary to figure out the factors affecting the use of U-service. Though the research related to ubiquitous computing has been vigorously conducted from the aspect of system and service provider, there have been very few studies that focus on the user's perspective. Therefore, this study attempts to figure out major factors which are dedicated to the development of ubiquitous computing and u-service, and that ultimately influence the u-business outcome. This study derived the factors that characterize u-service, such as ubiquity, contextual offer, reliability, invisibility, and confidentiality, which are then combined in the TAM model and carry out the path analysis. The research findings indicate that ubiquity affects both the perceived usefulness and perceived ease of use. The reliability and confidentiality were found to affect the perceived usefulness, whereas the contextual offer and invisibility turned out to influence the perceived ease of use. Finally, the relationship among the perceived usefulness, perceived ease of use, and the attitude toward using are identical with the previous research findings related to the technology acceptance model(TAM).

• The KIPS Transactions:PartB
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• v.9B no.5
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• pp.609-614
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• 2002

Watermarking is embedding a digital signal called as watermark into images to claim the ownership. In this paper, a new digital watermarking algorithm based on DCT (Discrete Cosine Transform) which enhances invisibility and robustness is proposed to improve contentional digital watermarking method using DCT. In the proposed method, it is possible to enhance invisibility and robustness using watermark reordering in which the relative significance of original DCT coefficients can be preserved in watermarked DCT coefficients, and the distortions of original DCT coefficients can be minimized. The experimental results show that the proposed method improves invisibility approximately 9～12[dB] and is more robust to various attacks than the conventional method.

• Journal of Contemporary Eastern Asia
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• v.21 no.1
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• pp.77-85
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• 2022

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.800-803
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• 2004

This paper presents a wavelet-based digital watermarking technique for still images. The digital watermarking considering human visual system (HVS) to increase the robustness and perceptual invisibility of digital watermark. The watermarking embedding is modified discrete wavelet transform (DWT) coefficients of the subbands of the images. The human visual system is number of factors that effect the noise sensitivity of human eyes that is considered to increase the robustness and perceptual invisibility of digital watermark. The watermark detection is blind watermark ( original image is not required ). Experimental results successful against attacks by image processing such as add noise, cropping, filtering, JPEG and JPEG2000 compression.