• 대한수학회보
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• 제51권1호
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• pp.229-235
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• 2014

We enumerate black and white colored d-ary trees with no leftmost ${\square}$-edges, which is a generalization of hybrid binary trees. Then the multi-colored hybrid d-ary trees with the same condition is studied.

• 대한수학회지
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• 제38권4호
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• pp.793-806
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• 2001

In this paper we consider the enumeration problem of permutations with partially forbidden positions, generalizing the notion of permutations with forbidden positions. .As an alternative approach to this problem, we investigate the permanent maximization problem over some classes of (0,1)-matrices which have a given number of 1's some of which lie in prescribed positions.

• 대한수학회지
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• 제43권3호
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• pp.553-561
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• 2006

In this paper, we give an alternative proof that the number of doubly alternating Baxter permutations is Catalan.

• 대한수학회논문집
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• 제28권4호
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• pp.649-667
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• 2013

In this paper we give an explicit formula for the total number of subgroups of a finite abelian $p$-group up to rank three.

• 산업경영시스템학회지
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• 제15권25호
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• pp.91-95
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• 1992

The aircraft schedule is the central of an airline's planning process, aimed at optimizing the deployment of airline's resources in order to maximize profits In this paper, the aircraft schedule is formulated as an integer programming model and the exact algorithm hared on enumeration method is proposed.

• 식물분류학회지
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• 제35권3호
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• pp.211-226
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• 2005

1980년에 출간된 이창복교수의 대한식물도감(大韓植物圖鑑)에는 선만실용임업편람(鮮滿實用林業便覽), Mori의 조선식물명휘(朝鮮植物名彙), 그리고 이창복교수의 여러 출전 문헌에서 언급된 비합법명등이 기재되어 있다. 그러나, 현재 여전히 다른 신간 식물도감에서 이런 잘못된 학명을 지속적으로 사용하고 있어, 이런 문제의 약 150여개 비합법명을 정리하여 출전별로 목록을 만들어 정리하였다. 본 연구에 언급된 이런 비합법명은 더 이상 문헌에서 인용하거나 언급되는 것은 바람직하지 않다.

• Journal of Computing Science and Engineering
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• 제6권2호
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• pp.127-140
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• 2012

In this paper, we focus on efficient construction of tightest matched subtree (TMSubtree) results, for keyword queries on extensible markup language (XML) data, based on smallest lowest common ancestor (SLCA) semantics. Here, "matched" means that all nodes in a returned subtree satisfy the constraint that the set of distinct keywords of the subtree rooted at each node is not subsumed by that of any of its sibling nodes, while "tightest" means that no two subtrees rooted at two sibling nodes can contain the same set of keywords. Assume that d is the depth of a given TMSubtree, m is the number of keywords of a given query Q. We proved that if d ${\leq}$ m, a matched subtree result has at most 2m! nodes; otherwise, the size of a matched subtree result is bounded by (d - m + 2)m!. Based on this theoretical result, we propose a pipelined algorithm to construct TMSubtree results without rescanning all node labels. Experiments verify the benefits of our algorithm in aiding keyword search over XML data.

• 대한교통학회지
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• 제18권1호
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• pp.27-34
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• 2000

이 연구는 최근 소비자 행동분석에서 많이 사용되고 있는 설문조사에 의한 Stated Preference의 방법론을 채택하여 항공여객수요의 가격탄력성을 분석하였다. 우리나라의 국내선 항공은 항공요금이 지금가지 인가제나 신고제로 규제되어 왔기 때문에 통상의 총량자료에 의한 회귀분석으로는 가격탄력성 도출이 어려우며 특별한 분석방법론을 필요로 한다. 이 연구에서는 항공여객에 대한 설문조사로 항공편과 철도, 버스, 승용차 등 대체교통수단과의 선택 여부에 대한 자료를 입수한 후, SP기법에 따른 Logit model로 분석하여 항공수요의 가격탄력성과 대체교통수단으로의 모드별 쉐어 변환율을 Sample Enumeration 방식에 의해 추정하였다 대체 가격탄력성은 -0.6∼-0.9의 값으로 밝혀졌으며 대체교통수단으로는 주로 철도를 선택하고 일부 버스를 선택하며 승용차는 거의 선택하지 않는 것으로 조사되었다.

• Journal of Power Electronics
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• 제18권5호
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• pp.1369-1379
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• 2018

In this paper, a model predictive torque control (MPTC) without the use of a weighting factor for surface mounted permanent-magnet synchronous machine (SPMSM) drive systems is presented. Firstly, the desired voltage vector is predicted in real time according to the principles of deadbeat torque and flux control. Then the sector of this desired voltage vector is determined. The complete enumeration for testing all of the feasible voltage vectors is avoided by testing only the candidate vectors contained in the sector. This means that only two voltage vectors in the sector need to be tested for selecting the optimal voltage vector in each control period. Thus, the calculation time can be reduced when compared with the conventional enumeration method. On the other hand, a novel cost function that only includes the dq-axis voltage errors between the desired voltage and candidate voltage is designed to eliminate the weighting factor used in the conventional MPTC. Thus, the control complexity caused by the tuning of the weighting factor is effectively decreased when compared with the conventional MPTC. Simulation and experimental investigation have been carried out to verify the proposed method.

• Fisheries and Aquatic Sciences
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• 제14권3호
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• pp.226-229
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• 2011

This study was conducted to develop a proficiency test (PT) specimen for the enumeration of Escherichia coli, a sanitary indicative bacterium, in molluscan bivalve shellfish. The common mussel Mytilus edulis was chosen as a matrix for the PT specimen. Mussels were artificially bioaccumulated for approximately 3 h with E. coli culture. After determining the homogeneity of samples, samples were distributed to 17 participants involved in the proficiency testing program. The enumeration of E. coli was performed by the most probable number method of the American Public Health Association. Statistical evaluations of the results obtained from inter- and intra-laboratory variation indicated no significant differences in the accuracy of these techniques between participants, indicating z-scores of ${\leq}{\pm}2$ and suggesting that preparation of the PT specimen for enumerating E coli in shellfish was successful.