• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.16-18
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• 2001

Despite extensive research on R-trees, most of the proposed schemes have not been integrated into existing DBMS due to the lack of protocol to provide consistency in concurrent environment. R-link tree is an acceptable data structure to deal with this issue., but still not enough. In this paper, we focus on a simplified predicate locking mechanism based on R-link tree for concurrency control and phantom protection. An in-memory operation control list (OCList) used to suspend some conflicting operations is designed here. The main features of this approach are (1) it can be implemented easily and do not need any extra information. (2) Only-one-lock is held when descending R-tree even when node split happens, while lock-coupling scheme is performed when ascending. No deadlocks are possible. (3) Searches and insertions are not unnecessarily restricted. (4) Insert and Delete phantom in R-link tree are avoid through beforehand predication.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06b
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• pp.507-509
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• 2012

심전도 질환 데이터는 일반적으로 분류기를 사용한 실험이 많다. 심전도 신호는 QRS-Complex와 R-R interval을 추출하는 경우가 많은데 본 실험에서는 R-R interval을 추출하여 실험하였다. 심전도 데이터의 분류 실험은 일반적으로 SVM(Support Vector Machine)과 MLP(Multilayer Perceptron)으로 실험되지만 본 실험은 Decision Tree를 사용하여 정확도 향상을 추구하였다. 그리고 정확도 비교 분석을 위해 SVM과 MLP 분류기 실험을 같이 수행하였고, 동일한 데이터와 간격으로 실험한 타 논문의 결과와 비교해 보았다. Decision Tree를 다른 분류기와 타 논문의 결과와 비교해 보니 정확도 부분에서는 Decision Tree가 가장 우수하였다.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.3
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• pp.363-371
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• 1994

This thesis investigates an expert system(ES) to propose fault restoration plan by utilizing tree search strategies. In order to cope with an extensive amount of data and frequent breaker switching operations in distribution systems, the database of system configuration is constructed by using binary trees. This remarkably enhances the efficiency of search algorithm and makes the proposed ES easily adaptable to system changes due to switching operations. The rule-base is established to fully utilize the meris of tree-structured database. The inferring strategy is developed mainly based on the best-first search algorithm to increase computation efficiency. The proposed ES has been implemented to efficiently deal with large distribution systems by reducing computational burden remarkably compared with the conventional ES's.

• Journal of the Korea Society of Computer and Information
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• v.8 no.3
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• pp.150-155
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• 2003

Multicasting, the transmission of data to a group, can be solved from constructing multicast tree, that is, the whole network is partitioned to some clusters and the clusters are constructed by multicast tree. This paper proposes an algorithm that reduces the multicast routing costs using a clustering method. Multicast tree is constructed by minimum-cost Steiner tree. It is important to solve the mnimum-cost Steiner tree problem in the multicast routing problems. Hence, this paper proposes a genetic algorithm for multicast routing problems using clustering method.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2003.05a
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• pp.206-213
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• 2003

Application of existing decision tree algorithms for Internet retail customer classification is apt to construct a bushy tree due to imprecise source data. Even excessive analysis may not guarantee the effectiveness of the business although the results are derived from fully detailed segments. Thus, it is necessary to determine the appropriate number of segments with a certain level of abstraction. In this study, we developed a stopping rule that considers the total amount of information gained while generating a rule tree. In addition to forwarding from root to intermediate nodes with a certain level of abstraction, the decision tree is investigated by the backtracking pruning method with misclassification loss information.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.12B
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• pp.1498-1505
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• 2009

In centralized control sensor network, tree-based multi-channel communication overcomes the recurrent channel switching and makes possible to transfer data simultaneously from different sources. In our paper, we propose a greedy algorithm named as NIT (Non-Intersecting Tree) that the trees can avoid inter-tree interference. We also propose channel switching technique by which trees can avoid link failure or area blocking due to external interference locally without rerunningthe algorithm and without interrupting the whole network. At first we applied our algorithm for a random topology and then we evaluate the performance of the network using NS-2 simulator. The results show that with the increasing of channel the throughputand delivery ratio are increased significantly. We got better performance than a using a recent proposed Tree-based Multi-Channel Protocol (TMCP).

• Journal of Environmental Science International
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• v.32 no.1
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• pp.11-24
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• 2023

This study aimed to provide preliminary data for the improvement of the tree doctor qualification test (first written test), which was newly created by enforcing the Forest Protection Act on June 28, 2018., The high demand for system improvement accelerated this study. The results were analyzeds through literature and questionnaire surveys. Writing test questions and the license of the tree doctor qualification exam are currently managed by the Korea Forestry Research Institute, and it is deemed that the test should be entrusted to Human Resources Development Service of Korea for fair and transparent management. Additionally, the plan for the improvement of the subject-wise scope of examination questions writing, difficulty of test questions, and acceptance rate of the first test should be prepared after public hearings or seminars related to the examination questions.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.769-772
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• 2007

공간 데이터의 효율적인 처리는 현대의 멀티미디어 데이터베이스에 있어서 대단히 중요한 역할을 하고 있다. 많은 응용분야에서 방대한 양의 공간 데이터는 보조기억장치(예: disk)에 저장이 되어 사용이 되고 공간 색인구조의 처리는 I/O에 대한 의존도가 크므로, I/O 연산의 병렬처리는 공간 색인구조의 질의반응시간을 현저하게 줄일 수 있다. 본 논문에서는 PR-tree라는 병렬형 공간 색인구조를 제안한다. PR-tree는 MXR-tree에 비해 높은 공간활용도와 빠른 처리시간을 보임으로써 공간 데이터베이스를 위한 효율적인 색인구조로 사용이 될 것으로 기대된다.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.5
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• pp.398-406
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• 1991

This paper presents a graphics accelerator for fast image generation. The accelarator has three major functional blocks: linear interpolator, multipliers and Edgee Painting Tree. Linear interpolator with coupled binary tree structure interpolates functional values of two end points. Two multipliers compute input values of interpolator in parallel. Mask pattern which removes out invalid data is generated by Edge Painting Tree. The proposed architecture in this paper is responsible for 64 pixels and can process about 5,900 10x10polygons per second.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.10
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• pp.1228-1241
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• 2011

This research compares the change in berberine content in liquid dye and the color and dye uptake of amur cork tree dyed silk upon thermal degradation treatment. Thermal degradation of amur cork tree extract and liquid dye of standard berberine was carried out at room temperature, $4^{\circ}C$ refrigeration, and $100^{\circ}C$ oven conditions for 0-192 hours. Amur cork tree dyed silk was treated in a $100^{\circ}C$ oven for 0-240 hours. The berberine content in liquid dye was measured by the relative abundance of the berberine peak in the HPLC-MS chromatograms. The color and dye uptake of dyed silk was measured using K/S value and colorimetric data. The berberine content in standard berberine dye was 2.4 times that of the amur cork tree extract. A similar result was observed between the K/S value of standard berberine dyed silk and that of amur cork tree dyed silk. The berberine dyed silk showed the highest dye uptake after 120 hours in a $100^{\circ}C$ oven. This result was similar to the change in a berberine content in liquid dye in a $100^{\circ}C$ oven treatment. The change of the K/S value of amur cork tree dyed silk and berberine content of amur cork tree extract was similar up to 24 hours. The result suggests that there is a direct relationship between the color change of amur cork tree dyed silk and the berberine content in amur cork tree dye.