• 전자공학회논문지CI
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• 제44권3호
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• pp.68-73
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• 2007

최근 무선센서 네트워크는 센서 영역 안에 수많은 센서 노드로 구성되어 있으며, 각각의 센서들은 강제적인 에너지 구속조건을 가지고 있으므로 효율적인 에너지 관리는 중요하다. WSN 응용 시스템에서 FEC(Forward error correction)는 데이터 전송의 에너지 효율성과 데이터 신뢰성을 증가시킨다. LDPC 코드는 FEC 코드중 하나로 코드워드의 길이가 커지면 다른 FEC 코드 보다 많은 부호화 작업을 필요로 하지만, 샤논의 용량 한계에 접근되어 있으며, 전송에너지의 감소와 데이터 신뢰도를 증가시키는데 사용되어진다. 본 논문에서는 WSN(Wireless Sensor Network)에서의 에너지 효율성 증가와 부호화의 복잡도를 줄이기 위하여 LDPC(Low-density parity-check) 코드의 패리티 체크 행렬의 생성에 Linear-Congruence 방법을 적용하였다. 결과적으로 본 논문에서 제안된 알고리즘은 부호화 에너지 효율성과 데이터의 신뢰도를 증가시켰다.

• 한국조리학회지
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• 제23권6호
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• pp.89-98
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• 2017

This research focused on recognizing and empirically testing a relationship between brand personality congruence and brand extension, which can lead to effective marketing strategies for the hotel industry. The objective of this research was to identify how customer's brand personality congruence affect brand extension and to then address what the most appropriate brand extension types for hotel brands are. This study offered a better approach to assess the broader impact of extension strategy for the marketer managers. The methodology for achieving these objectives were described in the following sections: developing measurements based on extensive reviews of literature and analyzing data utilized a exploratory factor analysis and a series of simple linear regression analyses. The result of this study showed customer's brand personality congruence had a great impact on the customer's positive attitude toward core brand. However, customer's attitude toward core brand had no impact on the updated attitude. The findings provided some theoretical and managerial implications for hotel operators.

• Safety and Health at Work
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• 제14권1호
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• pp.31-42
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• 2023

Background: This study analyzes the linear and non-linear effects of the hard and soft dimensions of job quality on the overall health of wage workers. It also examines the congruence or fit between the hard and soft job quality on the overall health of wage workers. Methods: This study measured thirty indicators that constitute job quality and reduced the indicators into twelve sub-dimensions of job quality using reflective factor analysis. In addition, this study derived two dimensions of job quality from the twelve subdimensions, namely the hard and soft job quality using formative factor analysis. This paper applied the response surface analysis to analyze the congruence effect between the two dimensions of job quality. Results: A logarithmic relationship was found between the dimension of hard job quality and the worker's overall health. This study also verified that the congruence effect between the two dimensions of job quality does not exist, and the combined effect of job quality is lower when the two dimensions of job quality are at the same level than the effect when either level of job quality is high or low. Conclusions: Although hard and soft job quality has independent positive effects on the overall health of wage workers, the two dimensions of job quality are not congruent or not in harmony with each other. This incongruence between hard and soft job quality, together with a higher impact of hard job quality, suggests that the role of soft job quality on overall health is relatively limited.

• 한국의학물리학회지:의학물리
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• 제9권2호
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• pp.105-113
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• 1998

고에너지 광자선을 발생시키는 의료용선형가속기의 선질은 경우에 따라 변이를 가져오게 된다. 이러한 변이를 정확하게 판정하여 줄 수 있는 방사선측정법의 활용은 매우 중요하다. 보편적으로 광자선의 측정에 있어서 전리함의 사용이 아주 빈번하였으나 전자포탈영상장치(EPID)의 등장은 새로운 방사선측정법에 대한 가능성의 시작을 예견해준다. 실험은 6MV 광자선의 대칭성, Light/Radiation congruence, 그리고 Wedge filter를 통한 간편한 에너지의 변화에측과 위치의 정확도에 대하여 측정을 시행하였다. 사실 방사선측정의 대표적인 방법은 물팬톰-전리함응 이용한 모델인데 본 실험에서는 영상의 화소가 지니는 디지탈 값을 적절한 소프트웨어로 읽어내어서 데이터를 환산하여 결과를 얻었다. 선행실험에서 얻은 상대선량률을 적용하여 대칭성에서는 조사야영역이 l0$\times$10$cm^2$ 일 때 횡축과 종축에서 1.2%, 1.2%로 비교적 오차가 적었다. 그리고 Light/Radiation field congruence 여부는 횡축이 0.3%, 그리고 종축이 0.2%로서 예상한 기대값에 접근하였다. 다음으로 wedge filter를 활용한 에너지의 변이와 위치의 정확도에 대한 움직임을 알 수 있었다.

• ETRI Journal
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• 제29권3호
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• pp.381-389
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• 2007

In this paper we propose a graph-theoretic method based on linear congruence for constructing low-density parity check (LDPC) codes. In this method, we design a connection graph with three kinds of special paths to ensure that the Tanner graph of the parity check matrix mapped from the connection graph is without short cycles. The new construction method results in a class of (3, ${\rho}$)-regular quasi-cyclic LDPC codes with a girth of 12. Based on the structure of the parity check matrix, the lower bound on the minimum distance of the codes is found. The simulation studies of several proposed LDPC codes demonstrate powerful bit-error-rate performance with iterative decoding in additive white Gaussian noise channels.

• 한국수학사학회지
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• 제34권5호
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• pp.165-191
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• 2021

The simple simultaneous linear congruence equation solution in 《Sunzi Suanjing孫子算經》 has developed into a systematic general solution in 《Shuxue Jiuzhang數書九章》. The most important parts of it is the creation of the Dayan Qiuyishu大衍求一術. The reason why 《Sanhak Jeongeui算學正義》 deals with the Dayanshu大衍術 which has lost its practicality in the calculation of astronomical calendar, is that one of the best achievement of traditional mathematics cannot be omitted. It is written with an emphasis on the disclosure of the calculation principle. It shows that Nam Byeong-gil南秉吉 and Lee Sang-hyeok李尙爀 had a fairly structural understanding of the Dayan Qiuyishu.

• 한국수학교육학회지시리즈A:수학교육
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• 제40권1호
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• pp.93-102
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• 2001

The world we live in is called the age of information. Thus communication and computers are doing the central role in it. When one studies the mathematical problem, the use of tools such as computers, calculators and technology is available for all students, and then students are actively engaged in reasoning, communicating, problem solving, and making connections with mathematics, between mathematics and other disciplines. The use of technology extends to include computer algebra systems, spreadsheets, dynamic geometry software and the Internet and help active learning of students by analyzing data and realizing mathematical models visually. In this paper, we explain concepts of transformation, linear transformation, congruence transformation and homothety, and introduce interesting, meaningful and visual models for teaching of a plane transformation geomeoy which are obtained by using Mathematica. Moreover, this study will show how to visualize linear transformation for student's better understanding in teaching a plane transformation geometry in classroom. New development of these kinds of teaching-learning methods can simulate student's curiosity about mathematics and their interest. Therefore these models will give teachers the active teaching and also give students the successful loaming for obtaining the concept of linear transformation.

• 대한수학회지
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• 제56권2호
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• pp.507-521
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• 2019

For any $m{\times}n$ nonbinary Boolean matrix A, its spanning column rank is the minimum number of the columns of A that spans its column space. We have a characterization of spanning column rank-1 nonbinary Boolean matrices. We investigate the linear operators that preserve the spanning column ranks of matrices over the nonbinary Boolean algebra. That is, for a linear operator T on $m{\times}n$ nonbinary Boolean matrices, it preserves all spanning column ranks if and only if there exist an invertible nonbinary Boolean matrix P of order m and a permutation matrix Q of order n such that T(A) = PAQ for all $m{\times}n$ nonbinary Boolean matrix A. We also obtain other characterizations of the (spanning) column rank preserver.

• 한국해양공학회지
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• 제9권2호
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• pp.61-70
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• 1995

The purpose of this paper is to calculate the excavation volume of unequal interval grid using nonlinear boundary in eathwork volume determination for reclamation of the foreshore. A congruence area formula by first and third equation is compared with trapezoidal, simpson formulas to earthwork volume. And nonlinear spot level method of unequal interval grid is compared with linear and nonlinear spot level method of equal interval grid excavation volume. As a result algorithm of derived area and volume formula should provide a better accuracy than linear and nonlinear spot level currently in use. Practical application of each method to the excavation volume is illustrated by digital elevation model of aerial photogrammetry and model test of aquarium.

• 대한수학회보
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• 제43권3호
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• pp.619-626
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• 2006

Let m be any positive integer, R be a ring with identity, $M_m(R)$ be the matrix ring of all m by m matrices eve. R and $G_m(R)$ be the multiplicative group of all n by n nonsingular matrices in $M_m(R)$. In this pape., the following are investigated: (1) for any pairwise coprime ideals ${I_1,\;I_2,\;...,\;I_n}$ in a ring R, $M_m(R/(I_1{\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $M_m(R/I_1){\times}M_m(R/I_2){\times}...{\times}M_m(R/I_n);$ and $G_m(R/I_1){\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $G_m(R/I_1){\times}G_m(R/I_2){\times}...{\times}G_m(R/I_n);$ (2) In particular, if R is a finite ring with identity, then the order of $G_m(R)$ can be computed.