• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.571-574
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• 2000

Seals in universal joint bearing are a important component reinforcing lubrication performance by holding a lubricant and preventing infiltration of dust, moisture, etc. There is a great difference in seal performance according to seal shape and bonding position. Therefore, in this study, as for the lib type seal and O-ring type seal, FEM analysis are conducted using Mooney-Rivlin Model. The results are indicate that O-ring having higher contact stress and larger contact area than lib type is more profitable.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.247-249
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• 1998

This paper has proposed an optimized universal motor for improving its performance and cost using FEM program. To do this, various design parameters are set such as air gap length, shape of stator and pole shoe, rotor slot, rotor shaft diameter, etc. As results, the optimized model has made good improvement compared with those of the initial.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.34-38
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• 2017

Objectives: The aim of this study was to evaluate the cyclic fatigue resistance of the ProTaper Universal D1 file (Dentsply Maillefer) under continuous and adaptive motion. Materials and Methods: Forty ProTaper Universal D1 files were included in this study. The cyclic fatigue tests were performed using a dynamic cyclic fatigue testing device, which had an artificial stainless steel canal with a $60^{\circ}$ angle of curvature and a 5 mm radius of curvature. The files were randomly divided into two groups (Group 1, Rotary motion; Group 2, Adaptive motion). The time to failure of the files were recorded in seconds. The number of cycles to failure (NCF) was calculated for each group. The data were statistically analyzed using Student's t-test. The statistical significant level was set at p < 0.05. Results: The cyclic fatigue resistance of the adaptive motion group was significantly higher than the rotary motion group (p < 0.05). Conclusion: Within the limitations of the present study, the 'Adaptive motion' significantly increased the resistance of the ProTaper Universal D1 file to cyclic facture.

• Tunnel and Underground Space
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• v.24 no.3
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• pp.243-254
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• 2014

The present study introduces a numerical technique to simulate the mechanical behavior of brittle rock, based on a grain-based model combined with Universal Distinct Element Code (GBM-UDEC). Using the technique, the microstructure of rock sample was represented as an assembly of deformable polygonal grains, and the failure process with the evolution of micro tensile cracks under compression was examined. In terms of the characteristics of strength and deformation, the behaviors of the simulated model showed good agreement with the observations in the laboratory-scale experiments of rock.

• MALSORI
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• no.63
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• pp.125-137
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• 2007

Recently, many techniques have been proposed to improve the noise robustness for speaker verification. In this paper, we consider the feature recombination technique in multi-band approach. In the conventional feature recombination for speaker verification, to compute the likelihoods of speaker models or universal background model, whole feature components are used. This computation method is not effective in a view point of multi-band approach. To deal with non-effectiveness of the conventional feature recombination technique, we introduce a subband likelihood computation, and propose a modified feature recombination using subband likelihoods. In decision step of speaker verification system in noise environments, a few very low likelihood scores of a speaker model or universal background model cause speaker verification system to make wrong decision. To overcome this problem, a reliable feature selection method is proposed. The low likelihood scores of unreliable feature are substituted by likelihood scores of the adaptive noise model. In here, this adaptive noise model is estimated by maximum a posteriori adaptation technique using noise features directly obtained from noisy test speech. The proposed method using subband-based reliable feature selection obtains better performance than conventional feature recombination system. The error reduction rate is more than 31 % compared with the feature recombination-based speaker verification system.

• Journal of the Korea Society of Computer and Information
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• v.27 no.11
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• pp.39-46
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• 2022

In this paper, we propose a multi-task model that can simultaneously predict general-purpose tasks such as part-of-speech tagging, lemmatization, and dependency parsing using the UD Korean Kaist v2.3 corpus. The proposed model thus applies the self-attention technique of the BERT model and the graph-based Biaffine attention technique by fine-tuning the multilingual BERT and the two Korean-specific BERTs such as KR-BERT and KoBERT. The performances of the proposed model are compared and analyzed using the multilingual version of BERT and the two Korean-specific BERT language models.

• Journal of the Korean Society for Library and Information Science
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• v.39 no.1
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• pp.147-166
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• 2005

The purpose of this study is to redefine the concept and scope of universal service and to develop universal service policy of South Korea for Korean reunification. The basic assumption of this study is that well developed universal service may contribute to the eventual reunification by ensuring equal access to information resources for the two peoples. The theoretical foundation of this study includes social capital and diffusion of innovations theory. This study uses policy analysis as both data collection and data analysis, more specifically qualitative policy analysis with triangulation for improving credibility. Data for the analysis were collected through legislation, other policy documents, and major agreements between North and South Korea related to informatization and unification. This study, identified the major characteristics of universal service and explored the current universal service in South Korea by analyzing major poicy instruments of South Korea. In addition, this study presented a great possibility of cooperating in telecommunication policy and telecommunication infrastructure. Consequently, this study proposed policy recommendations in five areas: 1) redefining the scope of universal service, 2) developing a unified telecommunication infrastructure, 3) developing policy instruments, 4) restructuring government organizations, and 5) creating a participatory universal service model for Korean reunification.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.5
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• pp.812-820
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• 1995

This paper proposes an approach of identifying nonlinear mappings from input/output data. The approach is based on the universal approximation by the fuzzy integration of local affine mappings. A connectionist model realizing the universal approximator is suggested by using a processing unit based on both the radial basis function and the weighted sum scheme. In addition, a learning method with self-organizing capability is proposed for the identifying of nonlinear mapping relationships with the given input/output data. To show the effectiveness of our approach, the proposed model is applied to the function approximation and the prediction of Mackey-Glass chaotic time series, and the performances are compared with other approaches.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.619-625
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• 2006

Amount of soil loss is important information for the proper water quality management, In this research, annual average soil loss of the Geum River basin was estimated using RUSLE (Revised Universal Soil Loss Equation) and GIS (Geographic Information System). Input data were manipulated using ArcGIS ver. 8.3. From crop field which constitute 8.2% of the Geum River Basin, annual average soil loss was estimated as 53.6 ton/ha/year. From the rice paddy field which constitutes 20% of the Geum River Basin, soil loss was estimated as 33.5 ton/ha/year, In comparison, forestry area which constitutes 61.8% of the basin discharged 2.8 ton/ha/year, It could be known from this research that appropriate measures should be implemented to prevent excessive soil loss from the agricultural areas.

• Journal of Information Processing Systems
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• v.11 no.1
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• pp.22-38
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• 2015

While Modern Standard Arabic is the formal spoken and written language of the Arab world; dialects are the major communication mode for everyday life. Therefore, identifying a speaker's dialect is critical in the Arabic-speaking world for speech processing tasks, such as automatic speech recognition or identification. In this paper, we examine two approaches that reduce the Universal Background Model (UBM) in the automatic dialect identification system across the five following Arabic Maghreb dialects: Moroccan, Tunisian, and 3 dialects of the western (Oranian), central (Algiersian), and eastern (Constantinian) regions of Algeria. We applied our approaches to the Maghreb dialect detection domain that contains a collection of 10-second utterances and we compared the performance precision gained against the dialect samples from a baseline GMM-UBM system and the ones from our own improved GMM-UBM system that uses a Reduced UBM algorithm. Our experiments show that our approaches significantly improve identification performance over purely acoustic features with an identification rate of 80.49%.