• Animal cells and systems
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• v.7 no.2
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• pp.133-137
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• 2003

Secreted proteins and membrane proteins play key roles in the formation, differentiation, and maintenance of multicellular organisms. In this study, we undertook to characterize these protein types in the central nervous system of the marine snail Aplysia kurodai using a yeast-based signal sequence trap method. One hundred and three cDNA clones were obtained by screening 300,000 clones from the signal sequence trap cDNA library. Of these, twelve were identical to previously identified Aplysia genes, 19 were related to known proteins in other organisms, and 54 clones were novel. These 54 new genes had high signal peptide scores or were found likely to contain a transmembrane domain sequence. Only 18 of the 103 clones proved to be false positive. The study demonstrates that the signal sequence trap method is an effective tool for Isolating Aplysia genes encoding secreted and membrane proteins.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.2
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• pp.126-133
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• 2022

This study proposes a suppression of zero sequence current (ZSC), which is caused by zero sequence voltage (ZSV) for a dual two-level inverter with single DC bus. Large output voltages enable the dual inverter with single DC bus to improve a system efficiency compared with single inverter. However, the structure of dual inverter with single DC bus inevitably generates ZSC, which reduces the system efficiency and causes a current ripple. ZSV is also produced by dead time, and its magnitude is determined by the DC bus and current direction. This study presents a novel space vector modulation method that allows the instantaneous suppression of ZSC. Based on a condition where a switching period is twice a sampling (control) period, the proposed control method is implemented by injecting the offset voltage at the primary inverter. This offset voltage is injected in half of the switching period to suppress the ZSC. Simulation and experiments are used to compare the proposed and conventional methods to determine the ZSC suppression performance.

• Proceedings of the KSRS Conference
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• v.2
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• pp.627-630
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• 2006

Sequential Pattern Mining is the mining approach which addresses the problem of discovering the existent maximal frequent sequences in a given databases. In the daily and scientific life, sequential data are available and used everywhere based on their representative forms as text, weather data, satellite data streams, business transactions, telecommunications records, experimental runs, DNA sequences, histories of medical records, etc. Discovering sequential patterns can assist user or scientist on predicting coming activities, interpreting recurring phenomena or extracting similarities. For the sake of that purpose, the core of sequential pattern mining is finding the frequent sequence which is contained frequently in all data sequences. Beside the discovery of frequent itemsets, sequential pattern mining requires the arrangement of those itemsets in sequences and the discovery of which of those are frequent. So before mining sequences, the main task is checking if one sequence is a subsequence of another sequence in the database. In this paper, we implement the subsequence matching method as the preprocessing step for sequential pattern mining. Matched sequences in our implementation are the normalized sequences as the form of number chain. The result which is given by this method is the review of matching information between input mapped sequences.

• Korean Journal of Remote Sensing
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• v.22 no.5
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• pp.457-462
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• 2006

Sequential Pattern Mining is the mining approach which addresses the problem of discovering the existent maximal frequent sequences in a given databases. In the daily and scientific life, sequential data are available and used everywhere based on their representative forms as text, weather data, satellite data streams, business transactions, telecommunications records, experimental runs, DNA sequences, histories of medical records, etc. Discovering sequential patterns can assist user or scientist on predicting coming activities, interpreting recurring phenomena or extracting similarities. For the sake of that purpose, the core of sequential pattern mining is finding the frequent sequence which is contained frequently in all data sequences. Beside the discovery of frequent itemsets, sequential pattern mining requires the arrangement of those itemsets in sequences and the discovery of which of those are frequent. So before mining sequences, the main task is checking if one sequence is a subsequence of another sequence in the database. In this paper, we implement the subsequence matching method as the preprocessing step for sequential pattern mining. Matched sequences in our implementation are the normalized sequences as the form of number chain. The result which is given by this method is the review of matching information between input mapped sequences.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.118-122
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• 2000

Nowadays, it is popular to use the spread spectrum watermarking algorithm for still image. But there is high error probability of the retrieved watermark in the spread spectrum owing to the correlation between image and spreaded watermark sequence. In this paper, two methods are proposed. One is Ordering Map Method and the other is Alteration of Image. Based on pixel value, the order by which the spreaded watermark bits is embedded is created in Ordering Map Method. By the covariance function between image and the spreaded sequence, image is altered in Alteration of Image. Hence, bit error of retrieved watermark is clearly reduced to zero by this two method.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.7
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• pp.17-21
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• 2008

As with the binary pseudo-random sequences q-ary m-sequences possess very good properties which make them useful in many applications. So we construct a class of Jacket matrices by applying additive characters of the finite field $F_q$ to entries of all shifts of q-ary m-sequence. In this paper, we generalize a method of obtaining conventional Hadamard matrices from binary PN-sequences. By this way we propose Jacket matrix construction based on q-ary M-sequences.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.4
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• pp.325-336
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• 2013

FlashLinQ, one of the typical D2D communication systems developed by Qualcomm, considers a single-tone communication based distributed channel-aware link scheduling method to realize the link scheduling process with low control overheads. However, considering the frequency selective fading effect of practical multi-path channel, the single-tone based SIR estimation causes a critical scheduling error problem because the received single-tone signal has quite different channel gain at each sub-carrier location. In order to overcome this problem, we propose a novel link scheduling method based on CAZAC (Constant Amplitude Zero Auto-Correlation) sequence for D2D communication system. In the proposed method, each link has a unique offset value set for the generation of CAZAC sequences. CAZAC sequences with the cyclic offsets are transmitted using multiple sub-blocks in the entire bandwidth, and then each device can obtain nearly full-band SIR using a good cyclic cross-correlation property of CAZAC sequence.

• Animal cells and systems
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• v.4 no.3
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• pp.267-272
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• 2000

Partial sequence of the mitochondrial cytochrome b gene was analyzed to investigate genetic variation from 10 geographic populations of Granulilittorina exigua in Korea. The sequence of 282 base pairs was determined by PCR-directed silver sequencing method. The sequences of two species within the genus Littorina reserved in NIH blast search were utilized to determine geographic variations of species referred. The levels of mtDNA sequence differences were 0.00-2.54% within populations and 0.71-4.43% between populations. There were four amino acid differences between representative species of the genera Granulilittorina and Littorina, but no differences within populations of the genus Granulilittorina. The UPGMA and the N-J trees based on Tamura-Nei genetic distance matrix were constructed, which showed that the genus Granulilittorina was divided into three groups such as eastern (even exception for Tokdo population), southern, and western regional populations. The degrees of genetic divergence within populations of each group were p=0.021, p=0.019, and p=0.018, respectively. The divergence between the eastern and southern populations was p=0.032, showing closer relationship than with the western populations (p=0.052). Based on the diverged time estimation, the eastern and southern populations of Granulilittorina exigua in Korea diverged from the western populations about 2.1 MYBP, and the eastern and southern populations diverged from each other about 1.3 MYBP.

• Genomics & Informatics
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• v.11 no.4
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• pp.272-276
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• 2013

Sequence analysis of the 16S rRNA gene has been widely used for the classification of microorganisms. However, we have been unable to clearly identify five Flavobacterium species isolated from a freshwater by using the gene as a single marker, because the evolutionary history is incomplete and the pace of DNA substitutions is relatively rapid in the bacteria. In this study, we tried to classify Flavobacterium species through multilocus sequence analysis (MLSA), which is a practical and reliable technique for the identification or classification of bacteria. The five Flavobacterium species isolated from freshwater and 37 other strains were classified based on six housekeeping genes: gyrB, dnaK, tuf, murG, atpA, and glyA. The genes were amplified by PCR and subjected to DNA sequencing. Based on the combined DNA sequence (4,412 bp) of the six housekeeping genes, we analyzed the phylogenetic relationship among the Flavobacterium species. The results indicated that MLSA, based on the six housekeeping genes, is a trustworthy method for the identification of closely related Flavobacterium species.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.10
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• pp.118-127
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• 2014

DNA data storage refers to any technique for storing massive digital data in base sequence of DNA and has been recognized as the future storage medium recently. This paper presents an information hiding method for DNA data storage that the massive data is hidden in non-coding strand based on DNA steganography. Our method maps the encrypted data to the data base sequence using the numerical mapping table and then hides it in the non-coding strand using the key that consists of the seed and sector length. Therefore, our method can preserve the protein, extract the hidden data without the knowledge of host DNA sequence, and detect the position of mutation error. Experimental results verify that our method has more high data capacity than conventional methods and also detects the positions of mutation errors by the parity bases.