• Journal for History of Mathematics
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• v.20 no.3
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• pp.1-16
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• 2007

In order to generalize theory of series in Iksan(翼算), we introduce a concept of double sequence of partial sums and elementary double sequence of partial sums, which play a dominant role in the study of double sequences of partial sums. We introduce a concept of finitely generated double sequence of partial sums and find a necessary and sufficient condition for those double sequences. Finally we prove a multiplication theorem for tetrahedral numbers and for 4 dimensional tetrahedral numbers.

• 열병합발전
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• s.48
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• pp.9-15
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• 2005

• Plant Journal
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• v.18 no.2
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• pp.32-40
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• 2022

In this study, we investigated the operation data of combined heat and power in accordance with the change of the inlet guide vane with partial load. The partial load 80% could close the inlet guide vane up to 24%, and the exhaust gas temperature could be increased by 52℃. The partial load 90% could close the inlet guide vane up to 12%, and the exhaust gas temperature could be increased by 23℃. At 80% of partial load with the thermal load tracking mode, the output could be increased up to 5.68 MW, the combined cycle efficiency increased by 0.73%, and the combined heat and power efficiency increased by 1.81%. At 90% of the partial load, the output could be increased up to 2.55 MW, the combined cycle efficiency increased by 0.32%, and the combined heat and power efficiency increased by 0.72%.

• Journal of Korean Society of Steel Construction
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• v.16 no.4 s.71
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• pp.425-432
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• 2004

Large studs were suggested not only for the design of steel-concrete composite bridges with simplified sections but also for the shear connection in precast decks requiring uniform distribution of shear pockets. Based on the push-out test results on studs with diameters of more than 25 mm, partial composite beams with 40%-degree shear connection were fabricated, and static tests were performed. The ultimate strength and horizontal shear load redistribution of partial composite beams, which have parameters of stud shank diameters and distribution, were evaluated, and group failure in the shear span was observed. Since the flexural strength of composite beams are dependent on the strength of their shear connection, the strength of the stud connection was estimated and it showed considerably higher shear strength. From the load-slip curves, the sufficient ductility and load redistribution of large studs were confirmed. Uniformly distributed large studs can provide proper ultimate behavior of composite beams.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.4
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• pp.259-267
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• 2018

The subset-sum problem is to find out whether or not the element sum of a subset within a finite set of numbers is equal to a given value. The problem is a well-known NP-complete problem, which is difficult to solve within a polynomial time. Genetic algorithm is a method for finding the optimal solution of a given problem through operations such as selection, crossover, and mutation. Dynamic programming is a method of solving a given problem from one or several subproblems. In this paper, we design and implement a genetic algorithm that solves the subset-sum problem, and experimentally compared the time performance to find the answer with the case of dynamic programming method. We selected a total of 17 test cases considering the difficulty in a set with 63 elements of positive number, and compared the performance of the two algorithms. The presented genetic algorithms showed time performance improved by 84% on 13 of 17 problems when compared with dynamic programming.

• Journal of the korean Society of Automotive Engineers
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• v.11 no.6
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• pp.3-16
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• 1989

본 고에서는 품질향상 측면보다는 실험계획법 자체에 중점을 두고 이를 소개하고자 한다. 실험게획의 일차적 목적은 어느 의미에서는 모형화 즉 반응치에 미치는 각 인자의 주효과의 교호작용 관게를 규명하는 것이라고 볼 수 있으며 방법론에서 전조합실시법과 부분실시법으로 구분할 수 있는데 부분실시법의 목적은 어떻게 하면 경제적으로 시험횟수를 최소화하되 전조합실시법의 효과를 낼 수 있는가 하는 것이다. Taguchi의 실험계획은 직교배열을 이용한 부분실시법에 근거를 두고 있다.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 1998.12a
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• pp.471-481
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• 1998

피승수를 승수로 곱하는 곱셈연산은 승수에 대한 많은 부분곱을 더하기 때문에 본질적으로 느린 연산이다. 특히, 큰 수를 사용하는 암호 프로세서에서는 매우 빠른 곱셈기가 요구된다. 현재까지 느린 연산의 개선책으로 radix 4, radix 8, 또는 radix 16의 변형 부스 알고리즘을 사용하여 부분곱의 수를 줄이려는 연구와 더불어 Wallace tree나 병렬 카운터를 사용하여 부분곱의 합을 빠르게 연산하는 방법이 연구되어 왔다. 본 논문에서는 암호 프로세서용 64$\times$64 비트 곱셈기를 구현하는데 있어서, 고속의 곱셈을 위하여 고속의 병렬 카운터를 제안하였으며, radix 4의 변형 부스 알고리즘을 이용하여 부분합을 만들고 부분합의 덧셈은 제안한 카운터를 사용하였다. 64$\times$64 비트 곱셈기를 구현함에 있어서 본 논문에서 제안된 카운터를 이용하는 것이 속도 면에서 Wallace scheme또는 Dadda scheme을 적용하여 구현하는 것 보다 31% 정도, Mehta의 카운터를 적용하여 구현하는 것 보다 21% 정도 개선되었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3A
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• pp.238-244
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• 2010

We propose a user selection method in multi-cell multiuser uplink system with the subspace interference alignment to maintain the high sum-rate capacity. The proposed method selects users whose interference to adjacent cells are strong and apply the subspace interference alignment to the users. The proposed method provides that the number of users performing the interference alignment reduces and the high total sum-rate is maintained. Simulation results exhibit the proposed method reduces the number of users who would decompose the channel for the subspace interference alignment by 50% when the required sum-rate is 90% of the maximal achievable sum-rate.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1998.10a
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• pp.511-514
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• 1998

• Journal for History of Mathematics
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• v.23 no.1
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• pp.53-66
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• 2010

This study concerns with partial sum of Fourier series, Fourier coefficients and the $L^1$-convergence of Fourier series. First, we introduce the $L^1$-convergence results. We consider equivalence relations of the partial sum of Fourier series from the early 20th century until the middle of. Second, we investigate the minor lineage of $L^1$-convergence theorem from W. H. Young to G. A. Fomin. Finally, we compare and reinterpret the $L^1$-convergence theorems.