• Journal of Broadcast Engineering
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• v.17 no.5
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• pp.876-890
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• 2012

In this paper, we investigated the performances of the distributed video codec with adaptive Gray code to apply for frame-difference signal. That is, the best cases and the worst cases were analyzed and compared by considering the statistical characteristics of the frame difference signal in view of the Gray code allocation. Through computer simulations, if 9-bit data for frame difference signal is generated for luminance signal with 8-bit definition and so n-bit is allocated to the quantized coefficient, we were able to find the best method to reduce the virtual channel noise by adding $256+2^{9-n-1}$ to the frame difference signal. Through computer simulation with test video sequences, it was shown that the performance difference between the best cases and the worst cases is larger than about 1.5dB at same rate. It is expected that the results in this paper are applicable for the transform-domain scheme as well as the pixel-domain scheme.

• Bulletin of the Korean Mathematical Society
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• v.55 no.3
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• pp.971-997
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• 2018

The parity of cyclotomic numbers of order 2, 4 and 6 associated with 4-cyclotomic cosets modulo an odd prime p are obtained. Hence the explicit expressions of primitive idempotents of minimal cyclic codes of length $p^n$, $n{\geq}1$ over the quaternary field $F_4$ are obtained. These codes are observed to be subcodes of Q codes of length $p^n$. Some orthogonal properties of these subcodes are discussed. The minimal cyclic codes of length 17 and 43 are also discussed and it is observed that the minimal cyclic codes of length 17 are two weight codes. Further, it is shown that a Q code of prime length is always cyclotomic like a binary duadic code and it seems that there are infinitely many prime lengths for which cyclotomic Q codes of order 6 exist.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4067-4071
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• 2021

The ¹³C (α,n)¹⁶O reaction cross-section is important data for nuclear physics, astrophysical, and neutrino physics experiments, however, they exhibit uncertainties due to the discrepancies in the experimental data. In this study, using the Nedis-2m program code, the energy spectrum of α-induced neutrons in a thin carbon target was calculated and the corresponding reaction cross-section was refined in the alpha particle energy range of 5-8 MeV. The results were used to calculate the intensity and energy spectrum of background neutrons produced in the liquid scintillator of KamLAND. The results will be useful in a variety of astrophysical and neutrino experiments especially those based on LS or Gd-LS detectors.

• Structural Monitoring and Maintenance
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• v.6 no.1
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• pp.67-84
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• 2019

Digital Image Correlation technique (DIC) is a non-contact optical method for rapid structural health monitoring of critical infrastructure. An innovative approach to DIC is presented using QR (Quick Response) code based random speckle pattern. Reinforced Cement Concrete (RCC) beams of size $1800mm{\times}150mm{\times}200mm$ are tested in flexure. DIC is used to extract Moment (M) - Curvature (${\kappa}$) relationships using random speckle patterns and QR code based random speckle patterns. The QR code based random speckle pattern is evaluated for 2D DIC measurements and the QR code speckle pattern performs satisfactorily in comparison with random speckle pattern when considered in the context of serving a dual purpose. Characteristics of QR code based random speckle pattern are quantified and its applicability to DIC is explored. The ultimate moment-curvature values computed from the QR code based random speckled pattern are found to be in good agreement with conventional measurements. QR code encrypts the structural information which enables integration with building information modelling (BIM).

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.49-52
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• 2000

The Multi-Code CDMA systems that are proposed as an effective transmission methodology in the IMT-2000 systems allow higher rate services under the IS-95 CDMA infrastructure. The Multi-Code CDMA systems convert the higher rate data into the lower rate by serial to parallel operation and spread the converted data streams by the multiple walsh codes, and its mobile receiver needs multiple walsh generators and data correlators to demodulate simultaneously multiple walsh code channels. Therefore, the number of data correlators is increased as the number of traffic channels increases. In this paper, we proposed the new structure of the data correlators using walsh overlay coding, the shared accumulator, and FWHT(Fast Walsh Hadamard Transform) algorithm for reducing the bottle-neck effect resulting the increase of the number of data correlators.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.4
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• pp.127-135
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• 1994

In this paper we propose an EWLD(Enhanced Weighted Levenshtein Distance) algorithm to organize code-string pattern matching linear array processor based on the mappting to an one-dimensional array from a two-dimensional matching matrix, and design a processing element(PE) of the processor, N PEs are required instead of NS02T in the processor because of the mapping. Data input and output between PEs and all internal operations of each PE are performed in bit-serial fashion. The bit-serial operation consists of the computing of word distance (WD) by comparison and the selection of optimal code transformation path, and takes 22 clocks as a cycle. The layout of a PE is designed based on the double metal $1.5\mu$m CMOS rule. About 1,800 transistors consistute a processing element and 2 PEs are integrated on a 3mm$\times$3mm sized chip.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.11
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• pp.1626-1634
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• 1993

In this paper we propose a coding scheme which combines source codes and error correcting codes in order to be robus to channel noise. One of the coding schemes that take into account both the source and the channel is the channel optimized quantizer (COQ) which simultaneously minimizes quantization noise and the noise due to channel errors. This paper deals with the problem of combining channel optimized quantizers with ECC to build an improved system. To be specific, we computed the performance of an n bit COQ and that of an n-1 bit COQ followed by an (n-1)/n punctured convolutional code. From this result whether or not the ECC are selected is determined by the number of allocated bits and the channel bit error rate. These results are applied to the image trans-mission method using DCT, and the system performances are evaluated.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.351-355
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• 2006

1990년대 후반 이후 등장한 N세대 N generation라는 신조어는 넓게는 '10대 후반과 20대 초반의 새로운 세대'라는 'new'의 개념에서의 N세대 new generation를, 좁게는 '네트워크 network를 자유자재로 다루는 세대' 또는 '네트워크 속에서 생활하는 세대' 라는 '디지털 유저 digital user'의 개념에서의 N세대 network generation를 의미한다. 다시 말해, N세대는 디지털 디바이스의 정보와 지식을 바탕으로 자유롭게 디지털 세상을 넘나드는 젊은 디지털 유저 층이다. 본 연구의 목적은 디지털 디바이스 프로덕트 광고의 한 사례를 기호학적으로 분석하여 '"디지털 디바이스+ N세대=디지털 코드"라는 광고공식'과 '외연과 내연이 합해져 "기술적 시니피앙과 감성적 시니피에"의 상호작용적 조합 interaction'을 찾아보는 것에 있다. 여기서는 광고 분석의 사례로써 삼성 KENOX V4 광고를 이용한다. KENOX V4 는 N세대를 겨냥한 디지털 디바이스 프로덕트이며, 이 광고는 '외국 브랜드를 제압하는 의미의 V'라는 코드를 사용하고 있다. 자기만의 주장을 당당하게 할 줄 아는 N세대가 소년기에 가졌던 한국이라는 자부심이 그가 성인기에 들어선 이후에도 V라는 승리의 표상으로 나타나고 있는 것이다. V4 광고의 이미지는 N세대를 상징하는 강력한 '디지털 코드digital code'를 담아내고 있으며, 그 V4의 메시지는 '4백만 화소'라는 '기술적 시니피앙 technological significant'과 '4가지 승리'라는 '감성적 시니피에 emotional signifie'의 상호작용적 조합을 구성하고 있다.

• Journal of the Korean Society for Library and Information Science
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• v.37 no.3
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• pp.71-71
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• 2003

본 연구는 국내 학술지의 표준화된 학술지 식별코드 체계인 KOJIC(KOrean Journal Identification Code)를 개발하는 것이 목적이다. 이 시스템을 개발하기 위하여 전통적인 자료식별 번호체계, 주요 국가서지번호, 그리고 국제적 또는 국가적 자료식별코드체계의 구조를 조사 분석한 다음, 유일성, 간편성, 조기성, 국제성, 그리고 확정성을 갖춘 KOJIC을 개발하였다. 이것은 6 자리의 알파벳 영문자와 숫자로 구성되는 코드이며, 한 개의 체크기호를 포함하고 있다.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.55.2-55.2
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• 2017

We present a numerical code for the random scattering histories of Lyman alpha photons in the intergalactic medium. The numerical code calculates the radiative transfer under generic three dimensional density, ionization fraction, and peculiar velocity fields based on N-body + radiation transfer simulations of the epoch of reionization. The code is tested with models having analytical solutions, which have idealized geometry and simplified velocity fields. The emergent line profiles can give constraints to the ionization structure around Lyman alpha sources in the early universe.