• Journal of the Korea Concrete Institute
• /
• v.28 no.5
• /
• pp.535-544
• /
• 2016

This paper aims at examining the effects of sustained load and elevated temperature on the time-dependent deformation of a carbon fiber reinforced polymer (CFRP) sheets bonded to concrete as well as the pull-off strength of single-lap shear specimens after the sustained loading period using digital images. Elevated temperature during the sustained loading period resulted in increased slip of the CFRP composites, whereas increased curing time of the polymer resin prior to the sustained loading period resulted in reduced slip. Pull-off tests conducted after sustained loading period showed that the presence of sustained load resulted in increased pull-off strength and interfacial fracture energy. This beneficial effect decreased with increased creep duration. Based on analysis of digital images, results on strain distributions and fracture surfaces indicated that stress relaxation of the epoxy occurred in the 30 mm closest to the loaded end of the CFRP composites during sustained loading, which increased the pull-off strength provided the failure locus remained mostly in the concrete. For longer sustained loading duration, the failure mode of concrete-CFRP bond region can change from a cohesive failure in the concrete to an interfacial failure along the concrete/epoxy interface, which diminished part of the strength increase due to the stress relaxation of the adhesive.

• Journal of Digital Convergence
• /
• v.17 no.9
• /
• pp.105-114
• /
• 2019

This study examined the causal relationship between CSV and brand image and consumers' behavioral intentions by structural equation model using psychological variables such as CSV intentionality and company-consumer identification. 198 questionnaires were used to test 8 hypotheses using Smart PLS 2.0. Results are as follows: First, two hypotheses were rejected that CSV had a negative effect on CSV intentionality and CSV intentionality had a negative effect on brand image. Second, CSV has a positive effect on company-consumer identification and company-consumer identification has a positive effect on brand image, purchase intention, and willingness to pay. This study suggests the necessity of enhancing customer participation and communication for the company to establish CSV strategies.

• Journal of Conservation Science
• /
• v.37 no.3
• /
• pp.220-231
• /
• 2021

The use of digital copies of film-based analog images and the introduction of digital radiographic imaging systems using image plates gradually replace the non-destructive radiationirradiation method of Cultural Heritage. The quality of images obtained from this technique is affected by conditions such as tube voltage, tube current, and exposure time, type of image acquisition medium, distance of the artifacts from the image acquisition medium, and thickness of artifacts. In this study, we evaluated the grayscale image obtained using GE's Computed Radiograhpy (CR) imaging system, the transmission characteristics of the X-ray source for each tree type (pine, chestnut, sawtooth oak, ginkgo) used in wooden Cultural Heritage, and the signal-to-noise ratio (SNR) and contrast. The GE's CR imaging were analyzed using the Duplex wire image quality indicator, line-pair gauges.

• The KIPS Transactions:PartC
• /
• v.9C no.1
• /
• pp.1-8
• /
• 2002

Digital image watermarking is a technique for the purpose of protecting the ownership of the image by embedding proprietary watermarks in a digital image. It is required for the digital image watermarking scheme to pursue the robustness against water marking attacks and the perceptual Invisibility more than usual in steganography area, to guarantee not a hidden watermarking algorithm but the publicity of water-marking algorithm details and hidden use of key, which can protect the unauthorized user access from detection. In this paper we propose a new copyright watermarking scheme, which is barred on one-way hash functions using ElGamal functions and modular operations. ElGamal functions are widely used in cryptographic systems. Our watermarking scheme is robust against LSB(least significant bit) attacks and gamma correction attack, and also perceptually invisible. We demonstrate the characteristics of our proposed watermarking scheme through experiments. It is necessary to proceed as the future work the algorithm of achieving at the same time both the pseudo-randomness for the steno-key generation and the asymmetric-key generation.

• Journal of Digital Convergence
• /
• v.11 no.5
• /
• pp.411-422
• /
• 2013

The purpose of this study is to analyze the impact of food corporations'sponsorship activities on Brand Images and Purchase Intension in professional sport industry in Korea. To accomplish the purpose, SPSS 18.0 Ver., had been conducted with 263 actual returned questionnaires. After the relevant literature reviews and analysis statistic data, three outcomes were deducted, those are, first, sponsorship factors for food corporations in professional sport industry significantly influenced on brand image. Second, Sponsorship factors for food corporations in professional sport industry significantly influenced on the purchase intension. Third, brand image of food corporation in professional sport industry significantly influenced on purchase intention. With this study, undiscovered several marketing strategies of food corporations with professional sport of Korea for their future marketing strategies could be discussed and proposed.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.12
• /
• pp.111-121
• /
• 2021

As the main carrier of information, digital image is becoming more and more important. However, with the popularity of image acquisition equipment and the rapid development of image editing software, in recent years, digital image counterfeiting incidents have emerged one after another, which not only reduces the credibility of images, but also brings great negative impacts to society and individuals. Image copy-paste tampering is one of the most common types of image tampering, which is easy to operate and effective, and is often used to change the semantic information of digital images. In this paper, a method to protect the authenticity and integrity of image content by studying the tamper detection method of image copy and paste was proposed. In view of the excellent learning and analysis ability of deep learning, two tamper detection methods based on deep learning were proposed, which use the traces left by image processing operations to distinguish the tampered area from the original area in the image. A series of experimental results verified the rationality of the theoretical basis, the accuracy of tampering detection, location and classification.

• Journal of Korea Multimedia Society
• /
• v.11 no.1
• /
• pp.96-105
• /
• 2008

The introduction of the digital media changed 21 century at time of database paradigm and the database paradigm called forth a big change in production process and industry of the animation. One of the characteristics of animation is that it has to newly produce all of the images. But due to the introduction of digital technology, the original copy of those images produced for animation can be saved. Also, those permanently saved data can easily produce new images through modification and composition. Therefore, this assignment will be focused on the usage of digital base and how it has made a difference in animation creative skills. In order to achieve the goal, I will be reviewing some examples and discuss about the future of animation for the next generation.

• Korean Journal of Optics and Photonics
• /
• v.15 no.2
• /
• pp.183-189
• /
• 2004

As high quality digital cameras become readily available, digital cameras are being used not only for simple picture recording but also as information storing media in various fields. However, due to the fact that the spectral responses of the camera sensors are different from color matching functions of the CIE standard observer, the color can not be measured using these cameras. This study shows a method for converting camera image to sRGB image, in which color information is preserved. The transfer matrix between camera output signals and CIE stimulus values was determined using a multiple regression method with Macbeth ColorChecker as target colors. The CIE stimulus values for camera output signals can be mapped with a transfer matrix, and these values are converted to sRGB signals. As the result of testing a Kodak DC220 digital camera, the average color difference of Macbeth ColorChecker between true and displayed colors was 2.1 $\Delta$ $E_{ab}$ $^{*}$.$^{*}$.

• Journal of Korea Multimedia Society
• /
• v.13 no.3
• /
• pp.457-466
• /
• 2010

In this paper, we propose a new method for detecting digital forgery that identify interpolated region between digital composited images. For detecting the interpolation factor and the tampered regions, we perform two algorithms: The first algorithm is to estimate the interpolation factors using the differential equation for forgery image along the horizontal, vertical, and diagonal directions, respectively; The second algorithm is to scan the interpolation factors along each direction for detection areas as the mask of the optical window size($64{\times}64$) in order to find out the forgery region. A detection map of the forgery is classified with the magnitude of estimated interpolation factors into colors. This detection map can be used to find out interpolated regions from the tampered image. Experimental results demonstrate the proposed algorithms are proven on several examples. We also show the proposed approach is to accurately detect interpolated regions from digital composite images.

• Journal of Korean Society of Archives and Records Management
• /
• v.19 no.3
• /
• pp.155-178
• /
• 2019

The study aims to analyze the characteristics and problems of raw image file formats, evaluate its suitability for the management of digital photographic records, and suggest the introduction method to utilize such format in public institutions. Raw image file formats feature reversibility and flexibility. However, most of them are proprietary file formats that depend on the digital camera manufacturer. The DNG format, which was developed to standardize raw image file formats, has received positive reviews from overseas public agencies. However, the DNG format is not fully recognized as a standard; hence, it is appropriate to use it tentatively until the standard raw format appears. On the other hand, the converted digital photo file format is not recognized as an original with legal authenticity. Therefore, in the short term, DNG files created by format conversion and original raw files should be encapsulated and preserved. Furthermore, it is necessary to redefine the baseline of the hash value and file size to recognize the legal authenticity only with DNG files in the long term.