• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.5C
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• pp.497-502
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• 2006

In this paper, we propose a digital image encryption method using adaptive interleaving and multiple random shuffling table to improve the existing encryption methods which use a fixed random shuffling table. In order to withstand the plaintext attack, at first, we propose a interleaving method that is adaptive to the local feature of image. Secondly, using the proposed interleaving only shuffling method and multiple shuffling method that is combined interleaving with existing random shuffling method, we encrypted image by shuffled the DPCM processed $8^*8$ blocks. Experimental results show that, the proposed algorithm is very robust to plaintext attack and there is no overhead bit.

• Journal of Korea Multimedia Society
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• v.10 no.1
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• pp.58-65
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• 2007

This dissertation proposes digital video protection algorithm lot moving image based on MPEG. Shuffling-based encryption algorithms using a fixed random shuffling table are quite simple and effective but vulnerable to the chosen plaintext attack. To overcome this problem, it is necessary to change the key used for generation of the shuffling table. However, this may pose a significant burden on the security key management system. A better approach is to generate the shuffling table based on the local feature of an image. In order to withstand the chosen plaintext attack, at first, we propose a interleaving algorithm that is adaptive to the local feature of an image. Secondly, using the multiple shuffling method which is combined interleaving with existing random shuffling method, we encrypted the DPCM processed 8*8 blocks. Experimental results showed that the proposed algorithm needs only 10% time of SEED encryption algorithm and moreover there is no overhead bit. In video sequence encryption, multiple random shuffling algorithms are used to encrypt the DC and AC coefficients of intra frame, and motion vector encryption and macroblock shuffling are used to encrypt the intra-coded macroblock in predicted frame.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.3
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• pp.121-129
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• 2002

Existing methods for optimization of sequences by random mutagenesis generate libraries with a small number of mostly deleterious mutations, resulting in libraries containing a large fraction of non-functional clones that explore only a small part of sequence space. Large numbers of clones need to be screened to find the rare mutants with improvements. Library display formats are useful to screen very large libraries but impose screening limitations that limit the value of this approach for most commercial applications. By contrast, in both classical breeding and in DNA shuffling, natural diversity is permutated by homologous recombination, generating libraries of very high quality, from which improved clones can be identified with a small number of complex screens. Given that this small number of screens can be performed under the conditions of actual use of the product, commercially relevant improvements can be reliably obtained.

• The Korean Journal of Applied Statistics
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• v.23 no.6
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• pp.1209-1216
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• 2010

We describe shuffling process of 48 HwaTu(Flower) cards from a mathematical aspect and give the number of shuffles that are needed to arrive at a state of randomness. We observe that the cards are shuffled much less times in usual plays, that results in much riskier outcomes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.11
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• pp.1507-1518
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• 2020

High-quality images have a lot of information, so sensitive data is stored by encryption for private company, military etc. Encrypted images can only be decrypted with a secret key, but the original data cannot be retained when attacked by the Shear attack and Noise pollution attack techniques that overwrite some pixel data with arbitrary values. Important data is the more necessary a countermeasure for the recovery method against attack. In this paper, we propose a random number generator PingPong256 and a shuffling method that rearranges pixels to resist Shear attack and Noise pollution attack techniques so that image and video encryption can be performed more quickly. Next, the proposed PingPong256 was examined with SP800-22, tested for immunity to various noises, and verified whether the image to which the shuffling method was applied satisfies the Anti-shear attack and the Anti-noise pollution attack.

• Korean Journal of Microbiology
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• v.39 no.2
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• pp.76-82
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• 2003

To prepare evolved PHB depolymerase with increased activity for PHB or P(3HB-co-3HV) compared to the activity of the original PHB depolymerase from Alcaligenes faecalis T1, random mutation of the cloned PHB depolymerase gene was performed by using a DNA shuffling method. A library of mutated PHB depolymerase genes from A. faecalis T1 was fused to the ice nucleation protein (INP) gene from Pseudomonas syringae in pJHCl 1 and approximately 7,000 transformants were isolated. Using M9 minimal medium containing PHB or P(3HB-co-3HV) as the carbon source, mutants showing alteration in PHB depolymerase activity were selected from the transformants. The PHB depolymease activity of the transformants was confirmed by the formation of halo around colony and the turbidity decrease tests using culture supermatants. The catalytic activity of PHB depolymerase of the best mutant II-4 for PHB or P(3HB-co-13 mol% 3HV) was approximately 1.8-fold and 3.2-fold, respectively, higher than that of the original PHB depolymerase. DNA sequence analysis revealed that three amino acid residues (Ala209Val, Leu258Phe, and Asp263Thr) were substituted in II-4. From the mutational analysis, it was presumed that the substitution of amino acids near catalytic triad to more hydrophobic amino acids enhance the catalytic activity of PHB depolymerase from A. faecalis T1.

• Journal of Microbiology
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• v.35 no.3
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• pp.228-233
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• 1997

The MTF1 gene of Saccharomyces cerevisiae encodes a 43 kDa MITOCHONDRIAL RNA polymerase specificity factor which recognizes mitochondrial promoters to initiate correct transcription. To better understand structure-function of the MTF1 gene as well as the transcription mechanism of mitochondrial RNA polymerase, two cold-sensitive alleles of the MTF1 mutation were isolated by plasmid shuffling method after PCR-based random mutagenesis of the MTF1 gene. The mutation sites were analyzed by nucleotide sequencing. These cs phenotype mtf1 mutants were respiration competent on the nonfermentible glycerol medium at the permissive temperature, but incompetent at 13.deg.C. The cs phenotype allele of the MTF1, yJH147, encoded an L146P replacement. The other cs allele, yJH148, contained K179E and K214M double replacements. Mutations in both alleles were in a region of Mtflp which is located between domains with amino acid sequence similarities to conserved regions 2 and 3 of bacterial s factors.

• Journal of fish pathology
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• v.24 no.3
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• pp.297-305
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• 2011

A trap identification system for isolating functional sequences to allow the constitutive expression of foreign protein from Edwardsiella tarda was developed. Using the green fluorescent protein (GFP) reporter-based trap system, various functional sequences to drive heterologous expression of the GFP were selectable in Escherichia coli host. However from the bioinformatic sequence analysis, all the segments predicted as regulatory regions were not native promoters actually existing upstream of endogenous E. tarda genes. Instead, a number of non-authentic sequences, possibly resulted from the random shuffling and/or intermolecular ligation were also proven to be able to display a potent GFP expression in the recombinant E. coli. Further analysis with selected clones showed that both authentic and non-authentic sequences could function in as a constitutive promoter, leading quite a consistent and stable GFP expression after repetitive subcultures. Microscopic examination also confirmed the uniform pattern of GFP expression in every host bacterium. Semi-quantitative assay of GFP showed that there was no clear relationship between expression levels and organizational features of the promoters trapped. Functional promoter-like elements achieved in the present study could be a good starting material for multivalent genetic engineering of E. tarda in order to produce recombinant vaccines in a cost-effective fashion.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.91-98
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• 2009

This paper presents a solution to error avalanche of deciphering where radio noise brings random bit errors in encrypted image data under ubiquitous environment. The image capturing module is to be made comprising data compression and encryption features to reduce data traffic volume and to protect privacy. Block cipher algorithms may experience error avalanche: multiple pixel defects due to single bit error in an encrypted message. The new fault tolerant scheme addresses error avalanche effect exploiting a three-dimensional data shuffling process, which disperses error bits on many frames resulting in sparsely isolated errors. Averaging or majority voting with neighboring pixels can tolerate prominent pixel defects without increase in data volume due to error correction. This scheme has 33% lower data traffic load with respect to the conventional Hamming code based approach.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.2
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• pp.97-103
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• 2023

Since most of the information is transmitted through the network, eavesdropping and interception by a third party may occur. Appropriate measures are required for effective, secure and confidential communication in the network. Steganography is a technology that prevents third parties from detecting that confidential information is hidden in other media. Due to structural vulnerabilities, information protected by encryption and steganography techniques can be easily exposed to illegitimate groups. In order to improve the limitations of LSB where the simplicity and predictability of the hiding method exist, I propose a technique to improve the security of the message to be hidden based on PRNG and recursive function. To enhance security and confusion, XOR operation was performed on the result of selecting a random bit from the upper bits of the selected channel and the information transformed by the RS-box. PSNR and SSIM were used to confirm the performance of the proposed method. Compared to the reference values, the SSIM and PSNR of the proposed method were 0.9999 and 51.366, respectively, confirming that they were appropriate for hiding information.