• 산업경영시스템학회지
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• 제19권39호
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• pp.9-18
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• 1996

Many algorithms have been developed for optimizing the asymmectric traveling salesman problem known as a representative NP-Complete problem. The most efficient ones of them are branch and bound algorithms based on the subtour elimination approach. To increase efficiency of the branch and bound algorithm. number of decision nodes should be decreased. For this the minimum bound that is more close at the optimal solution should be found or an effective bounding strategy should be used. If the optimal solution has been known, we may apply it usefully to branching. Because a good feasible solution should be found as soon as possible and have similar features of the optimal solution. By the way, the upper bound solution in branch and bound algorithm is most close at the optimal solution. Therefore, the upper bound solution can be used instead of the optimal solution and information of which can be applied to new branching criteria. As mentioned above, this paper will propose an effective branching rule using the information of the upper bound solution in the branch and bound algorithm. And superiority of the new branching rule will be shown by comparing with Bellmore-Malone's one and carpaneto-Toth's one that were already proposed.

• 환경위생공학
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• 제5권2호
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• pp.100-104
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• 1990

The geometrical branching pattern was studied through the time by a few parameters: the branching lengths, angles and number of branches. Ratios of moving amounts of nutrients between branches was decreased more in a terminal branch than in a proximal one. As the time increased, the more branches and leaves were also increased, while the influx of sunlight was decreased in the lower portion of inner crown which increased the mortality rate of branches.

• 대한수학회지
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• 제38권1호
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• pp.25-35
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• 2001

In this paper we consider an age dependent branching process whose particles move according to a Markov process with continuous state space. The Markov process is assumed to the stationary with independent increments and positive recurrent. We find some sufficient conditions for he Markov motion process such that the empirical distribution of the positions converges to the limiting distribution of the motion process.

• 대한수학회지
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• 제36권6호
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• pp.1115-1132
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• 1999

We consider a supercritical multitype age dependent branching process. We define a stochastic process Zf(t) which is a functional of the empirical age distribution. When the limit of the expectation of this functional vanishes we4 find some sufficient conditions for the asymptotic normality of the mean of f with respect to the empirical age distribution at time t.

• Journal of Chest Surgery
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• 제45권5호
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• pp.338-341
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• 2012

Vascular ring, caused by Kommerell's diverticulum and ligamentum arteriosum, in a patient with right aortic arch and mirror image branching is extremely rare. A 10-month-old boy with coughing and stridor was diagnosed as having tracheo-esophageal stenosis, which is caused by a vascular ring with Kommerell's diverticulum, ligamentum arteriosum, right aortic arch, and mirror image branching. Kommerell's diverticulum was successfully resected via a left thoracotomy. The patient has been free from tracheo-esophageal stenosis for a year after the surgery.

• International Journal of CAD/CAM
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• 제12권1호
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• pp.29-37
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• 2012

A new algorithm has been developed to construct surface from the contours having branches and the final smooth surface is obtained by the reversible Catmull-Clark subdivision. In branching, a particular layer has more than one contour that correspond with at least one contour at the adjacent layer. In the next step, three-dimensional composite curve is constructed from contours of a layer having correspondence with at least one contour at the adjacent layer by inserting points between them and joining the contours. The points are inserted in such a way that the geometric center of the contours should merge at the center of the contours at the adjacent layer. This process is repeated for all layers having branching problems. Polyhedra are constructed in the next step with the help of composite curves and the contours at adjacent layer. The required smooth surface is obtained in the proposed work by providing the level of smoothness.

• Journal of applied mathematics & informatics
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• 제14권1_2호
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• pp.157-172
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• 2004

An age-dependent branching process where disasters occur as a renewal process leading to annihilation or survival of all the cells, is considered. For such a process, the total mean sojourn time of all the cells in the system is analysed using the regeneration point technique. The mean number of cells which die in time t and its asymptotic behaviour are discussed. When the disasters arrival as a Poisson process and the lifetime of the cells follows exponential distribution, elegant inter- relationships are found among the means of (i) the total number of cells which die in time t (ii) the total sojourn time of all cells in the system upto time t and (iii) the number of living cells at time t. Some of the existing results are deduced as special cases for related processes.

• Communications for Statistical Applications and Methods
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• 제18권6호
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• pp.809-816
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• 2011

A tree-indexed autoregressive(AR) process is a time series defined on a tree which is generated by a branching process and/or a deterministic splitting mechanism. This short article is concerned with conditional heteroscedastic structure of the tree-indexed AR models. It has been usual in the literature to analyze conditional mean structure (rather than conditional variance) of tree-indexed AR models. This article pursues to identify quadratic conditional heteroscedasticity inherent in various tree-indexed AR models in a unified way, and thus providing some perspectives to the future works in this area. The identical conditional variance of sisters sharing the same mother will be referred to as the branching heteroscedasticity(BH, for short). A quasilikelihood but preliminary estimation of the quadratic BH is discussed and relevant limit distributions are derived.

• Journal of the Korean Data and Information Science Society
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• 제25권5호
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• pp.1137-1149
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• 2014

Since the bifurcating autoregressive (BAR) model was developed by Cowan and Staudte (1986) to analyze cell lineage data, a lot of research has been directed to BAR and its generalizations. Based mainly on the author's works, this paper is concerned with a contemporary review on the BAR in terms of an overview and perspectives. Specifically, bifurcating structure is extended to multi-cast tree and to branching tree structure. The AR(1) time series model of Cowan and Staudte (1986) is generalized to tree structured random processes. Branching correlations between individuals sharing the same parent are introduced and discussed. Various methods for estimating parameters and related asymptotics are also reviewed. Consequently, the paper aims to give a contemporary overview on the BAR model, providing some perspectives to the future works in this area.

• 한국약용작물학회지
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• 제2권2호
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• pp.140-145
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• 1994

형질이 고정되지 않은 도입 삼도시호의 유용초형을 선발하고자 다변량 해석법에 의해 개체간의 유전적 거리를 추정하고 이를 ‘기초로 Cluster analysis로 초형군을 분류를 하였던바 그 결과를 요약하면 다음과 같다. 1. 시호의 지상부 및 지하부 8개 형질을 대상으로 Complete linkage cluster 방법 에 의해 초형을 분류한 결과 6개 군(群)으로 분류할 수 있었다. 최초 분지 착생절위가 낮은 개체는 분지수가 많아 다분지형으로 최초분지 착생절위가 높은 개체는 분지수가 적어 소분지형 초형으로 구분되었다. 2. 초형 II군(群)과 VI군(群)은 다분지형으로 그리고 I군(群), III군(群), IV군(群) 및 V군(群)은 소분지형으로 분류되었다. 3. 시호의 건근중은 분지수와 고도(高度)로 유의(有意)한 정상관(正相關)을 보였으며, 최초분지 착생결위와는 유의힌 부(負)의 상관(相關)을 나타내었다.