• Journal of Korea Multimedia Society
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• v.17 no.11
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• pp.1279-1285
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• 2014

In this paper, we propose on image encryption method which uses NC(Non-linear Cycle) and 2D CAT(Two-Dimensional Cellular Automata Transform) in sequence to encrypt medical images. In terms of the methodology, we use NC to generate a pseudo noise sequence equal to the size of the original image. We then conduct an XOR operation of the generated sequence with the original image to conduct level 1 NC encryption. Then we set the proper Gateway Values to generate the 2D CAT basis functions. We multiply the generated basis functions by the altered NC encryption image to conduct the 2nd level 2D CAT encryption. Finally, we verify that the proposed method is efficient and extremely safe by conducting an analysis of the key spatial and sensitivity analysis of pixels.

• Annual Conference of KIPS
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• 2005.05a
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• pp.989-992
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• 2005

CAT(Computer Adaptive Testing : 컴퓨터 기반 적응적 검사)는 기존의 종이 시험지에서 이루어지던 시험과 달리 수험자에게 적절한 맞춤식 출제로 보다 정확한 수험자의 능력 판단 및 빠른 수험진행을 가능케 하였다. 기존의 CAT는 많은 인원과 문제가 있어야만 그 결과에 신뢰성이 있다고 알려져 있다. CAT의 대표적인 알고리즘인 SPRT와 EXSPRT-R을 이용하여 10명의 적은 인원으로 JLPT 4급 기출문제를 적용한 실험을 하였다. SPRT 에서는 인원수와, 문제 난이도를 무시한 결과로 인하여 만족 할만한 결과를 얻지 못하였으나, EXSPRT-R의 경우에는 적은 인원에서도 충분히 CAT를 이용할 수 있음을 발견할 수 있었다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07a
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• pp.88-90
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• 2005

컴퓨터 개별적응 검사(CAT: Computerized Adaptive Testing)란 각 학습자 수준에 적절한 형태의 검사를 개별적으로 실시함으로써 짧은 시간 안에 적은 수의 문항으로도 측정하고자 하는 제 특성을 보다 정확하고 효율적으로 측정할 수 있게 하는 기법이다. 이는 학습자 중심의 수준별 교육을 위한 학습 도구로서 이용될 수 있다. 본 연구에서는 문항반응이론 기반의 CAT를 학습에 적용시킴으로써 학습자의 평가결과에 따라 즉각적인 피드백을 통한 개별학습을 할 수 있고 일정수준의 성취단계에 이를 때까지 스스로 부족한 부분에 대한 평가를 계속 실시하여 완전학습에 도달할 수 있는 새로운 형태의 CAT 기반 학습시스템을 제시한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.393-396
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• 2010

A secure and novel watermarking system based on complemented Maximum Length Cellular Automata (MLCA) and Two-Dimension Cellular Automata Transform (2D CAT) is proposed. In this watermarking scheme, the original watermark which is first encrypted by complemented MLCA with the private keys, and the encrypted watermark is embedded into the CAT domain of the cover image. Experiment results show that this new method is more secure and provides robust performance against watermarking attacks.

• Korean Journal of Veterinary Research
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• v.60 no.4
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• pp.229-232
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• 2020

A 15-year-old, spayed, female American shorthair cat presented with recurrent corneal sequestrum in the right eye. The cat had undergone superficial keratectomy twice for corneal sequestrum treatment 5 and 11 months previously. Two layers of porcine small intestinal submucosa (SIS; Vetrix BioSIS®) were applied to the surgical corneal defect after keratectomy. Thereafter, clinical signs, such as lacrimation, blepharospasm, and corneal ulcer, disappeared 50 days postoperatively. Moreover, the application of SIS with keratectomy prevented recurrence until 651 days after surgery. SIS could be applied as an additional bioscaffold for surgical repair of corneal sequestrum recurring after superficial keratectomy alone in cats.

• Journal of Korean Society of Forest Science
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• v.68 no.1
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• pp.32-36
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• 1985

Megagametophyte tissues of Pinus densiflora were subjected to study the inheritance of acid phosphatase (ACP), alcohol dehydrogenase (ADH) and catalase (CAT) isozymes by starch gel zone-electrophoresis. At least three or four zones were segregated for ACP isozyme. However, as one isozyme of ACP-A zone was separated clearly, only that isozyme was analysed. Five isozyme phenotypes (A1-A5), observed in ACP-A zone, were segregated to a simple Mendelian ratio, suggesting that these are controlled by five codominant alleles existed at ACP-A locus. Two zones of activity were segregated in the gels after staining for ADH, the more anodal zone (ADH-A) of the two was invariant in our materials. Three isozyme phenotypes (B1-B3) were observed in ADH-B zone and these variants showed a 1:1 segregation pattern, suggesting that each variant is controlled by three codominant alleles at ADH-B locus. A total of five isozyme phenotypes, composed of multiple bands, were observed in CAT isozyme. The segregation of these phenotypes in heterozygous trees did not show any significant deviation from a 1:1 segregation. Therefore, the genetic control of CAT isozyme in Pinus densiflora seeds seems to be based on a single locus (CAT-A) with Five codominant alleles ($A_1-A_5$).

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.12
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• pp.1101-1107
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• 2007

this paper, integrity analysis in Korean region using GPS, modernized GPS, Galileo, SBAS and GBAS is given. The simulation results show that Cat. I requirement can be met using modernized GPS and Galileo alone, however, Cat. II and III are not met even augmenting SBAS because of VPL. A more efficient augmentation such as GBAS reduces VPL to meet Cat. II and III requirements in Korean region. This result will be used to design and implement not only an augmentation system but also regional satellite navigation system.

• BMB Reports
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• v.30 no.4
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• pp.269-273
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• 1997

Heptocvte-specific expression induced by Hepatitis B virus (HBV) enhancer 2-core gene promoter was examined in various hepatocyte and non-hepatocyte cell lines. using non-viral and retroviral vector systems in which chloramphenicol acetyltransferase (CAT) is used as a reporter. The non-viral plasmid containing the HBV enhancer 2-core promoter exhibited 22 and 66% of CAT activities in hepatoma cell lines. HepG2 and Hep3B, respectively when compared with CAT activity expressed by CMV promoter. The CAT activities, however. were found to be marginal in other tested hepatoma cell lines as well as mouse primary hepatocytes and non-hepatocytes. The HBV enhancer 2 located upstream the CMV promoter did not affect the CMV promoter activity nor provided hepatocyte-specific expression. Transfection of retroviral plasmid DNA containing the HBV enhancer 2-core promoter as an internal promoter exhibited high and specific CAT expression in HepG2 and Hep3B cell lines but the activity value was 5 to 10 fold lower than the non-viral plasmid with identical promoter. These results suggest that the usage of HBV enhancer 2-core promoter for liver specific expression is limited to certain vectors and hepatocyte cell lines.

• Atmosphere
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• v.22 no.3
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• pp.321-330
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• 2012

Generation mechanisms of the three moderate-or-greater (MOG)-level clear-air turbulence (CAT) encounters over South Korea are investigated using the Weather Research and Forecasting (WRF) model. The cases are selected among the MOG-level CAT events occurred in Korea during 2002-2008 that are categorized into three different generation mechanisms (upper-level front and jet stream, anticyclonic flow, and mountain waves) in the previous study by Min et al. For the case at 0127 UTC 18 Jun 2003, strong vertical wind shear (0.025 $s^{-1}$) generates shearing instabilities below the enhanced upper-level jet core of the maximum wind speed exceeding 50 m $s^{-1}$, and it induces turbulence near the observed CAT event over mid Korea. For the case at 2330 UTC 22 Nov 2006, areas of the inertia instability represented by the negative absolute vorticity are formed in the anticyclonically sheared side of the jet stream, and turbulence is activated near the observed CAT event over southwest of Korea. For the case at 0450 UTC 16 Feb 2003, vertically propagating mountain waves locally trigger shearing instability (Ri < 0.25) near the area where the background Richardson number is sufficiently small (0.25 < Ri < 1), and it induces turbulence near the observed CAT over the Eastern mountainous region of South Korea.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.63-68
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• 2002

A cDNA encoding a putative member of cathepsin B of the thiol pretense superfamily was cloned from a cDNA library of the mulberry longicorn beetle, Apriona germari. Sequence analysis of the cDNA encoding the cathepsin B of A. germari (AgCatB) revealed that the 972 bp cDNA has an open reading frame of 324 amino acid residues. The deduced protein sequence of the AgCatB showed high homology with cathepsin B of the insects, Bombyx mori (47.3% amino acid identity), Helicoverpa armigera (46.6%) and Sarcophaga peregrina (45.6%), and the lowest homology with Aedes aegypti (33.2%). The AgCatB contains six disulfate bonds typical for cysteine pretenses. The three amino acid positions Cys-109, His-267, and Asn-287 which are conserved, active sites characteristic for cathepsin B, were also found. Phylogenetic analysis further confirmed that the AgCatB has a close relationship with that of B. mori, H. armigera and S. peregrina.