• 한국위성정보통신학회논문지
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• 제7권1호
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• pp.21-26
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• 2012

우리나라는 지난 20여 년 디지털 정보기술 강국을 지향해 왔지만 선진국에서 이미 투자를 시작한 양자 정보 과학 분야에 대한 연구 및 투자는 거의 이루어지지 않았으며, 양자 정보 통신 기술의 수준 또한 개발 선진국들에 비해 턱없이 부족한 상황이다. 최근, 양자역학에 기반을 두고 있는 양자 정보 처리 및 통신에 대한 연구가 세계적으로 활발히 진행 중이다. 90년대부터 본격화된 양자정보이론의 연구는 양자 컴퓨팅, 양자 통신, 양자 정보이론 등의 분야에서 발전해오고 있으며, 90년대 말에 이르러 양자 암호 통신 및 양자 알고리즘 등의 분야에서 큰 연구 성과를 나타내기 시작하였다. 본 논문에서는, 양자 통신 시스템에서 효율적인 양자 신호 전송 및 검출을 위해 직교 시퀀스를 이용한 효율적인 양자 신호 검출 방안에 대해 논하고자 한다.

• Journal of Microbiology and Biotechnology
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• 제34권6호
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• pp.1322-1327
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• 2024

The accurate and rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) holds significant clinical importance. This work presents a new method for detecting methicillin-resistant Staphylococcus aureus (S. aureus) in clinical samples. The method uses an aptamer-based colorimetric assay that combines a recognizing probe to identify the target and split DNAzyme to amplify the signal, resulting in a highly sensitive and direct analysis of methicillin-resistance. The identification of the PBP2a protein on the membrane of S. aureus in clinical samples leads to the allosterism of the recognizing probe, and thus provides a template for the proximity ligation of split DNAzyme. The proximity ligation of split DNAzyme forms an intact DNAzyme to identify the loop section in the L probe and generates a nicking site to release the loop sequence ("3" and "4" fragments). The "3" and "4" fragments forms an intact sequence to induce the catalytic hairpin assembly, exposing the G-rich section. The released the G-rich sequence of LR probe induces the formation of G-quadruplex-hemin DNAzyme as a colorimetric signal readout. The absorption intensity demonstrated a strong linear association with the logarithm of the S. aureus concentration across a wide range of 5 orders of magnitude dynamic range under the optimized experimental parameters. The limit of detection was calculated to be 23 CFU/ml and the method showed high selectivity for MRSA.

• 미생물학회지
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• 제32권3호
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• pp.215-221
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• 1994

Bacillus megaterium ATCC 14945의 penicillin G acylase 유전자의 염기배열을 결정하였다. 이 유전자에는 2,406 염기쌍으로 이루어진 하나의 open reading frame이 존재하는데, 개시코돈의 5' 위쪽에서 Shine-Dalgarno 배열과 promoter로 여겨지는 부분을 발견하였으며, 종결코돈의 3' 아래쪽에서 rho-independent한 전사종결체와 dby사한 구조를 발견하였다. 염기배열로부터 폴리펩티드의 아미노산 배열을 유추하였다. 이 폴리펩티드의 분자량은 91,983 Da이었으며, 아미노 말단 부이에 signal sequence가 존재하였다. 이 아미노산 배열을 여러 다른 penicillin G acylase의 아미노산 배열과 비교하고 분리 정제한 효소를 SDS-polyacrylamide gel 전기영동으로 분석한 결과로부터 이 효소는 92kDa의 전구체로 해독된 후 processing 과정을 거쳐 각각 25kDa과 61kDa의 ${\alpha}$-, ${\beta}$-단위체로 구성됨을 알 수 있었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -1
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• pp.478-481
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• 2002

In this paper, the zerotrees of DWT is proposed to be used in a speech based digital watermarking for digital images. Since in this research work the raw speech and its content are used as a watermark signal, in the watermarking scheme, the PCM coded speech signal is embedded into a sequence of images. The performance of the scheme is evaluated by the PSNR obtained from the watermarked images and the strength of attacks the embedded speech signal can survive. Moreover, since in this research work the contents contained in the speech is used to identify the specific information hidden in the embedded signal. The speech signal after being extracted from the watermarked images is played back to the listeners to determine whether its content is intelligible or not. The experimental results show impressive performance of the scheme implementing our proposed technique, judged by the higher robustness obtained form the embedded signal against various types of attack, including brightness/contrast enhancement, Twirling, highpass filtering and JPEG compression standard.

• BMB Reports
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• 제35권5호
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• pp.513-517
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• 2002

We describe a new method for identifying the sequences that signal the start of translation, and the boundaries between exons and introns (donor and acceptor sites) in human mRNA. According to the mandatory keyword, ORGANISM, and feature key, CDS, a large set of standard data for each signal site was extracted from the ASCII flat file, gbpri.seq, in the GenBank release 108.0. This was used to generate the scoring matrices, which summarize the sequence information for each signal site. The scoring matrices take into account the independent nucleotide frequencies between adjacent bases in each position within the signal site regions, and the relative weight on each nucleotide in proportion to their probabilities in the known signal sites. Using a scoring scheme that is based on the nucleotide scoring matrices, the method has great sensitivity and specificity when used to locate signals in uncharacterized human genomic DNA. These matrices are especially effective at distinguishing true and false sites.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권12호
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• pp.3182-3196
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• 2012

In this paper, we present a new LED (Light Emitting Diode) mood lighting system interacting with smartphones based on the generation of different light sequences. In the proposed system, one light sequence is considered to be one unit of the service contents, which is then transmitted through a network and played in an LED lighting system. To this end, we propose a novel generation scheme using a smartphone, and a decoding/playing mechanism in an LED lighting system. The lighting sequences have a fixed period divided into predefined time units. Two modes - basic and interpolation - are supported in each time unit when playing a color sequence. In the basic mode, the color is maintained for the entire time unit, whereas in the interpolation mode the color is interpolated. The sequence is decoded and played in the lighting circuit by changing the duty cycle of a PWM (Pulse Width Modulation) signal. A demonstration system of the overall proposed method was using smartphones, a server and an LED lighting system. The results from this experiment show the validity and applicability of the proposed scheme.

• 한국자기공명학회논문지
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• 제1권1호
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• pp.7-20
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• 1997

The mapping of the spin-spin relaxation time T2 in pixed-by-pixel was suggested as a quantitative diagnostic tool in medicine. Although the CPMG pulse sequence has been known to be the best pulse sequence for T2 measurement in physics NMR, the supplied pulse sequence by the manufacture of MRI system was able to obtain the maximum of 4 CPMG images. Eight or more images with different echo time TEs are required to construct a reliable T2 map, so that two or more acquisitions were required, which easily took more than 10 minutes. 4-echo CPMG imaging pulse sequence was modified to generate the maximum of 8 MR images with evenly spaced echo time TEs. In human MR imaging, since patients tend to move at least several pixels between the different acquisitions, 8-echo CPMG imaging sequence reduces the acquisition time and may remove any misregistration of each pixel's signal for the fitting T2. The resultant T2 maps using the theoretically simulated images and using the MR images of the human brain suggested that 8 echo CPMG sequence with short echo spacing such as 17∼20 msec can give the reliable T2 map.

• 한국항행학회논문지
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• 제8권2호
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• pp.163-168
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• 2004

본 논문에서는 HDR-WPAN(high data rate wireless personal area network) 시스템의 CAZAC sequence 특성을 이용한 주파수 동기 알고리즘을 제안하고, 신호 성상도 및 EVM(error vector magnitude)를 통해 성능을 분석해 본다. 제안된 방식에서 주파수 옵셋은 자기상관성이 우수한 12개의 CAZAC sequence 가운데 두 개 sequence의 각 샘플간 위상오차를 추정하였으며, 추정된 위상오차는 다음 sequence 내 각각의 샘플에 곱해지면서 위상오차를 보상하게 된다. 두 개의 sequence로 주파수 옵셋을 보상한 후 남은 잔류 주파수 옵셋은 샘플 당 최대 0.002도 이내가 되며 DQPSK의 경우 20[dB]에서 EVM의 허용 기준값을 만족할 수 있음을 컴퓨터 시뮬레이션을 통해 확인한다.

• Journal of the Optical Society of Korea
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• 제8권2호
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• pp.59-64
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• 2004

The response of a single-mode fiber to a sinusoidally modulated input has been studied to see its utility in measuring system performance in the presence of fiber nonlinearities. The sinusoidally modulated signal models an alternating bit sequence of ones and zeros in on-off keying. The sinusoidal response of normally dispersive fiber shows a strong correlation with eye-opening penalty (EOP) over a wide range of the nonlinearity parameter N (0.1 ＜ N$^2$＜ 100). This result implies that the measurement of the sinusoidal response can be an alternate way of measuring EOP without having a long sequence of randomly modulated input bits. But in the anomalous dispersion region, the sinusoidal response has a much more limited range of application to estimate system performance.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1998년도 학술발표대회 논문집 제17권 1호
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• pp.357-360
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• 1998

DS/CDMA system rejected narrow-band interference and additional White Gaussian noise which are occured at multipath, intentional jammer and multiuser to share same bandwidth in mobile communication systems. Because of having not sufficiently obtained processing gain which is related to system performance, they were not effectively suppressed. In this paper, an matched filter channel model using backpropagation neural network based on complex multilayer perceptron is presented for suppressing interference of narrow-band of direct sequence spread spectrum receiver in DS/CDMA mobile communication systems. Recursive least square backpropagation algorithm with backpropagation error is used for fast convergence and better performance in matched filter receiver scheme. According to signal noise ratio and transmission power ratio, computer simulation results show that bit error ratio of matched filter using backpropagation neural network improved than that of RAKE receiver of direct sequence spread spectrum considering of con-channel and narrow-band interference.