• International journal of advanced smart convergence
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• v.11 no.4
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• pp.163-169
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• 2022

In this paper, we propose a data hiding technique that effectively hides confidential data in the LSB of an image pixel by using the characteristics of the neighboring pixels of the image and the encryption techniques. In the proposed technique, the boundary surface of the image and the flat surface with little change in pixel values are investigated. At the boundary surface of the image, 1 bit of confidential data is encrypted and hidden in the LSB of the boundary pixel to preserve the characteristics of the boundary surface. In the pixels of the plane where the change in pixel value is small, 2 bits secret data is encrypted and hidden in the lower 2 bits of the corresponding pixel. In this way, when confidential data is hidden in an image, the amount of confidential data hidden in the image is greatly increased while maintaining excellent image quality. In addition, the security of hidden confidential data is strongly maintained. When confidential data is hidden by applying the proposed technique, the amount of confidential data concealed increases by up to 92.2% compared to the existing LSB method. The proposed technique can be effectively used to hide copyright information in commercial images.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.17 no.1
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• pp.17-24
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• 2024

In this paper, we propose a highly secure technique to hide confidential data in image pixels using a quadruple encryption techniques. In the proposed technique, the boundary surface where the image outline exists and the flat surface with little change in pixel values are investigated. At the boundary of the image, in order to preserve the characteristics of the boundary, one bit of confidential data that has been multiply encrypted is spatially encrypted again in the LSB of the pixel located at the boundary to hide the confidential data. At the boundary of an image, in order to preserve the characteristics of the boundary, one bit of confidential data that is multiplely encrypted is hidden in the LSB of the pixel located at the boundary by spatially encrypting it. In pixels that are not on the border of the image but on a flat surface with little change in pixel value, 2-bit confidential data that is multiply encrypted is hidden in the lower 2 bits of the pixel using location-based encryption and spatial encryption techniques. When applying the proposed technique to hide confidential data, the image quality of the stego-image is up to 49.64dB, and the amount of confidential data hidden increases by up to 92.2% compared to the existing LSB method. Without an encryption key, the encrypted confidential data hidden in the stego-image cannot be extracted, and even if extracted, it cannot be decrypted, so the security of the confidential data hidden in the stego-image is maintained very strongly. The proposed technique can be effectively used to hide copyright information in general commercial images such as webtoons that do not require the use of reversible data hiding techniques.

• Journal of KIISE:Databases
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• v.31 no.1
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• pp.13-22
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• 2004

With the proliferation of multimedia data, there is an increasing need to support the indexing and retrieval of high-dimensional image data. Although there have been many efforts, the performance of existing multidimensional indexing methods is not satisfactory in high dimensions. Thus the dimensionality reduction and the approximate solution methods were tried to deal with the so-called dimensionality curse. But these methods are inevitably accompanied by the loss of precision of query results. Therefore, recently, the vector approximation-based methods such as the VA- file and the LPC-file were developed to preserve the precision of query results. However, the performance of the vector approximation-based methods depend largely on the size of the approximation file and they lose the advantages of the multidimensional indexing methods that prune much search space. In this paper, we propose a new index structure called the GC-tree for efficient similarity search in image databases. The GC-tree is based on a special subspace partitioning strategy which is optimized for clustered high-dimensional images. It adaptively partitions the data space based on a density function and dynamically constructs an index structure. The resultant index structure adapts well to the strongly clustered distribution of high-dimensional images.

• Journal of architectural history
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• v.12 no.4 s.36
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• pp.49-62
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• 2003

Vesely explains, the main source of our confusion and nihilism comes most probably from the ambiguous relationship between modem architecture, technology and aesthetics. Also, to overcome such crucial problems, many theorists recently emphasize to take part in cultural civilization and to preserve creative genes of great culture that is based on our interpretation of 'ethical and mythical nucleus of mankind,' rather than in technical modernization that constitutes a sort of subtle destruction of mytho-ethical nucleus of a society. They for architecture also strongly stress on a mythopoetic imagination and an ontological construction of building, which could make a form symbolic and mythical rather than mathematical and aesthetic representation. On this point, 'myth' becomes a vital idea for constructing and construing architectural form and space. And it is also one of the essential concepts to understand both the motive power of cultural continuation of place and the meaning of architecture. Nevertheless, its meaning and the citation of word in architectural essay are still obscure. It might be because the original concept of myth not only has been lain in the matter of philosophical contemplation. Thus, the intention of the research is focused on lightening the meaning of myth in architectural term. Especially, it is, first, concentrated on interpreting philosopher Ernst Cassirer's reflections which were written in order to emphasize the importance of 'mythical consciousness' for the world's cultural civilization. And, the second, it will continue to interpret the myth as a sign within the semiotic concept of Charles Sanders Peirce, and further to emphasis the significance of mythic signs for the continuance of artistic and cultural idea including architecture. The contents of the paper is not that of architectural planning and design methodology, rather architectural philosophy and epistemology. Nevertheless, in regard to architecture, the research will, against today's un-discriminated use of symbolic motifs and instrumental representation of form, suggest a concrete architectural and aesthetic theory of myth and sign, especially of the relationship between the idea of semiology and the function of cultural continuity.

• KIEAE Journal
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• v.13 no.5
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• pp.89-96
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• 2013

Green roofs can reduce surface water runoff, provide a habitat for wildlife moderate the urban heat island effect, improve building insulation and energy efficiency, improve the air quality, create aesthetic and amenity value, and preserve the roof's waterproofing. Green roofs are mainly divided into three types : intensive, simple-intensive, and extensive. Especially, extensive roof environment is a harsh one for plant growth; limited water availability, wide temperature fluctuations, high exposure to wind and solar radiation create highly stressed environment. This study, aimed at extensive green roof, was carried out on the rooftop of the library at Seoul Women's Univ. from October to November, 2012 and from March to August, 2013. To suggest the most effective vegetation model for biodiversity and heat island mitigation, surface temperatures were monitored by each vegetation model. We found that herbaceous plants of Aster sphathulifolius, Aceriphyllum rossii and Belamcanda chinensis, shrub of Syringa patula 'Miss Kim', Thymus quinquecostatus var. japonica, Sedum species can mixing each other. Among them, the vegetation models including Sedum takesimense, Aster sphathulifolius, Thymus quinquecostatus var. japonica was more effective on the surface temperature mitigation, because the species have the tolerance and high ratio of covering, and also in water. Especially, in the treatment of bark mulching, they helped to increase the temperature of vegetation models. In the case of summer, temperature mitigation of vegetation models were no significant difference among vegetation types. Compared to surface temperature of June, July and August were apparent impact of temperature mitigation, it shows that temperature mitigation are strongly influenced by substrate water content.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.5
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• pp.437-445
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• 2016

Recently, polyurethane foam has been used in various industry fields to preserve temperature environment of structures, and a wide range of loads from the static to the dynamic are imposed on the material during a life period. The biggest characteristic of polyurethane foam is porosity as being polymeric material, and it is generally known that insulation performance of the material strongly depends on internal void size. In addition, polyurethane foam's mechanical behavior has high dependence on strain rate and temperature as well as being highly non-linear ductile for compression. In the non-linear compressive behavior, volume fraction of voids and elastic modulus decrease as strain increases. Therefore, in this study, temperature-dependent viscoplastic-damage constitutive model was developed to describe the non-linear compressive behavior with the aforementioned features of polyurethane foam.

• Journal of Yeungnam Medical Science
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• v.21 no.1
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• pp.101-107
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• 2004

Diffuse alveolar hemorrhage is a rare but serious and frequently life-threatening complication of a variety of conditions. The first goal in the management of patients with diffuse alveolar hemorrhage is to achieve or preserve stability of the respiratory status. Subsequently, the differential diagnosis is aimed at the identification of a remediable cause of the alveolar hemorrhage. The most common causes of diffuse alveolar hemorrhage with glomerulonephritis are microscopic polyangiitis and Wegener's granulomatosis, followed by Goodpasture syndrome and systemic lupus erythematosus. Microscopic polyangiitis (MPA) is a distinct systemic small vessle vasculitis affecting small sized vessels with few or no immune deposits and with no granulomatosus inflammation. The disease may involve multiple organs such as kidney, lung, skin, joint, muscle, gastrointestinal tract, eye, and nervous system. MPA is strongly associated with antineutrophil cytoplasmic autoantibody (ANCA) that is a useful serological diagnostic marker for the most common form of necrotizing vasculitis. Our report concerns a case of microscopic polyangiitis with diffuse alveolar hemorrhage in a 54-year-old man. He was admitted to our hospital due to dyspnea upon exertion and recurrent hemoptysis. Laboratory findings showed hematuria, proteinuria and deterioration of renal function. In the chest CT scan, diffuse ground glass appearance was seen in both lower lungs. A lung biopsy revealed small vessel vasculitis with intraalveolar hemorrhage and showed a positive reaction to against perinuclear ANCA. The patient was treated with prednisolone and cyclophosphamide. Chest infiltration decreased and hemoptysis and hypoxia improved. He is still being followed up in our hospital with a low dose of prednisolone.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.5
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• pp.620-631
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• 2015

A total of 59 lactic acid bacteria (LAB) strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA) sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L.) plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC $43971^T$, Micrococcus luteus ATCC $4698^T$ and Escherichia coli ATCC $11775^T$ were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at $100^{\circ}C$), but the antimicrobial activity was eliminated after treatment at $121^{\circ}C$ for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0), but became inactive under neutral and alkaline condition (pH 7.0 to 9.0). In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory.

• Smart Media Journal
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• v.6 no.3
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• pp.21-28
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• 2017

There is growing interest in the use of cloud services these days because the amount of sensitive physical information related to u-fitness-based exercise management increase in explosive. However, it is possible to illegally access information stored in a cloud server, and to find out who owns the information, even, to illegally deduce an association among the information stored in its memory. The cloud server may also intentionally pass over the owner's legitimate operation requests such as modification and deletion of stored information, and may lose or damage information due to its malfunction. So, it is strongly required to solve the above problems because we can not trust the cloud server entirely. In this paper, we propose a protocol to preserve the privacy of the owner for u-Fitness-based exercise management in a cloud computing environment. And we show that our proposed architecture is applicable in real environment through security analysis and performance analysis.

• Journal of the Korean GEO-environmental Society
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• v.12 no.11
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• pp.13-21
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• 2011

To recover basic functions of river such as water control, irrigation, environment, culture, a national river improvement project, the four river restoration projects were currently planned and under construction in Korea. This project is designed to preserve cultural assets and ecosystem from flooding, for that reason, environmentally friendly materials of construction are strongly emphasized. In this study, the soil and cement admixtures are developed. And, the compaction test and the unconfined compressive strength test to evaluate applicability of probiotics as environmentally friendly materials are conducted the soil and cement admixtures. As a result, the probiotic culture was not active in completely dried specimen to obtain accurate mixing proportion. It indicates that the probiotics cannot influence on the development the soil and cement admixtures. A further research will focus on the effect of response between polysaccharide environmentally friendly soil stabilizer and natural specimen.