• Journal of Mechanical Science and Technology
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• v.20 no.11
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• pp.1781-1789
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• 2006

Fourier methods are not generally an appropriate approach in the investigation of faults signals with transient components. This work presents the application of a new signal processing technique, the Hilbert-Huang transform and its marginal spectrum, in analysis of vibration signals and faults diagnosis of gear. The Empirical mode decomposition (EMD), Hilbert-Huang transform (HHT) and marginal spectrum are introduced. Firstly, the vibration signals are separated into several intrinsic mode functions (IMFs) using EMD. Then the marginal spectrum of each IMF can be obtained. According to the marginal spectrum, the wear fault of the gear can be detected and faults patterns can be identified. The results show that the proposed method may provide not only an increase in the spectral resolution but also reliability for the faults diagnosis of the gear.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.6
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• pp.284-289
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• 2002

The transmission networks do not consist of perfect conductors and a percentage of the power generated is therefore lost before it reaches the loads. Since this network loss contributes to the cost of suppling power to consumers, it must be considered that the most efficient dispatch and location of generators and loads are to be achieved. In this paper, marginal loss factors are calculated for 12 load levels that represent the impact of marginal network losses on nodal prices at the transmission network connection points at which generators are located. Based on comparison analysis of marginal loss factors on 12 load levels, we found the MLF characteristics in KOREA.

• Communications for Statistical Applications and Methods
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• v.15 no.4
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• pp.605-614
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• 2008

Oh (2008) has proposed the one-sided likelihood ratio test of the equality of two agreement measures. However the use of this test may be limited since the computations of test statistic and critical value are not easy. We propose a test for comparing two dependent agreements using some well known tests for marginal homogeneity, for instance, Bhapkar test, Stuart-Maxwell test. Data obtained from 2008 world figure skating championship ladies single is analyzed for illustration purposes.

• Korean Journal of Organic Agriculture
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• v.21 no.2
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• pp.125-137
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• 2013

The Purpose of this paper is to estimates consumers' willingness to pay for Urban Agriculture Park attributes. we analysis the marginal WTP by choice experiment method. Choice experiment (CE) is designed to elicit the marginal WTP differences among urban agriculture park attributes (garden scales, learning and experience area, leisure and relaxation area and fund). The results of multinomial logit model are meaningful, the total marginal WTP on the urban agriculture park attributes is 18,852 won. gardens scales is 2,949 won, learning and experience area is 11,284 won, leisure and relaxation area is 4,619 won. In the current laws, the facilities related to urban agriculture park is not. Taking advantage of the new urban agriculture park, Amendments of the law is required.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.1
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• pp.9-17
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• 1992

Proper resource allocation is also a very important topic in power system problems, especially in operation and planning. One such is optimal maintenance problem in operation and planning. Least cost and highest reliability should be the subjects to be pursued. A probabilistic operation simulation model developed recently by authors is applied to the proboem of optimal maintenance scheduling. Three different methods are compared, marginal maintenance cost, levelized risk and maintenance space. The method by the marginal maintenance costs shows the least cost, the highest reliability and the highest maintenance outage rates. This latter characteristics may considerably influence the results of genetation planning, because the usual maintenance outages obtained from the other methods have shown to be lower.

• Journal of Ginseng Research
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• v.14 no.1
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• pp.44-49
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• 1990

Effect of liming material application on the prevention or cure of Mn toxicity symptoms including marginal leaf chlorosis in 3-year-old ginseng plants grown in acidic soils were investigated. It was found that the ratio of Fe to Mn was above about 0.5 and the ratio of Mn to Fe was below about 2.00 in 4-year old ginseng leaves when liming materials were applied in field experiments. It was apparent that the occurrence of marginal leaf chlorosis was decreasing affected by application of Ca, Mg and Fe. The appearance of marginal leaf chlorosis was decreased to about 78 percent in 4-year-old ginseng and to about 69 percent in 5-year-old ginseng, and then the fresh root weight was increased up to 66 percent in 4-year ginseng plants.

• Journal of Plant Biology
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• v.33 no.1
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• pp.31-40
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• 1990

Procambium developed in the histogenetical zone below the marginal meristem. The development of procambium is correlated with the developmental stage of the leaf. As long as the marginal cells are crescent-shaped, the first-order procambium develops. When the marginal cell becomes wedge-shaped, the higher order procambium appears. The reticulated venation is developed through forking and anastomosis. The meshes of the first order enlarge in the process of leaf growth and the meshes of the second and third order develop in the meshes of the first-order through the differentiation of the residual meristem. Therefore, the venation is hierachically arranged and is as recognizable from the thickening of the veins. The outermost vein is produced parallel to the leaf margin, in which the differences between the costal and intercostal parts of the marginal meristem are removed. The endodermis and pericycle differentiate from the same mother cell. The procambium and sclerenchyma originate from a common source during the first developmental stage. A small cellular cluster lies within the parenchyma at the upper and lower sides of the procambial trace and differentiates into sclerenchyma.

• Journal of Technologic Dentistry
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• v.41 no.1
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• pp.1-7
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• 2019

Purpose: The objectives of this study was to evaluate clinical adaptation of dental prostheses printed by 3 dimensional(3D) printing technology. Methods: Ten study models were prepared. Ten specimens of experimental group were printed by 3D printing(3DP group). As a control group, 10 specimens were fabricated by casting method on the same models. Marginal gaps of all specimens were measured to evaluate clinical adaptation. Marginal adaptations were measured using silicone replica technique and measured at 8 sites per specimen. Wilcoxon's signed-ranks test was used for statistical analysis(${\alpha}=0.05$). Results: Means of marginal adaptations were $95.1{\mu}m$ for 3DP group and $75.9{\mu}m$ for CAST group(p < 0.000). Conclusion : However, the mean of the 3DP group was within the clinical tolerance suggested by the previous researchers. Based on this, dental prosthesis fabricated by 3D printing technology is considered to be clinically acceptable.

• Annual Conference on Human and Language Technology
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• 2019.10a
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• pp.297-300
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• 2019

문서 요약은 길이가 긴 원본 문서의 의미는 유지한 채 원본보다 짧은 문서나 문장을 생성하는 자연어 처리 태스크이다. 본 논문에서는 Maximal Marginal Relevance(MMR)를 이용한 sequence-to-sequence 문장 추출 모델을 이용하여 의미가 중복되는 문장을 최소화하는 문장을 추출하고 추출된 문장을 sequence-to-sequence 모델을 통해 요약문을 생성하는 2단계 문서 요약 모델을 제안한다. 실험 결과 MMR을 활용하지 않았던 기존의 방법론보다 Rouge 성능이 향상되었다.

• 대한치과보철학회:학술대회논문집
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• 2001.11a
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• pp.64-64
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• 2001