• Journal of the Korean Society of Mechanical Technology
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• v.13 no.3
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• pp.73-79
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• 2011

In this study, an analytical realization of end-milling system was introduced using recursive parametric modeling analysis. Also, the numerical mode analysis of end-milling system with different conditions was performed systematically. In this regard, a recursive least square modelling algorithm and the natural mode for real part and imaginary one was discussed. This recursive approach (RLSM) can be adopted for on-line end-milling identification. After experimental practice of the end-milling, the end-milling force was obtained and it was used for the calculation of FRF (Frequency response function) and mode analysis. Also the FRF was analysed for the prediction of a end-milling system using recursive algorithm.

• Nuclear Engineering and Technology
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• v.26 no.4
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• pp.570-577
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• 1994

The loss of water in the carbon steel balls and water region of the end shield for CANDU 6 reactor could lead to significant temperature gradient through the end shield structure which amy result in the excessive deformation. With an assumed end shield drained scenario, the heat deposition rates were calculated through the end shield associated with the central fuel channel during full power operation as an initial step to thermal stress analysis. The drained case was compared with that of water present normal case in therms of heat deposition rater and the total heating throughout the end shield regions. The compared results show that the heat deposition and the total heating remain almost the same between the two cases. It was found that the change of volume integrated flux in the end shield regions due to the loss of water contribute a negligible effect on the heat deposition in this region.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.8
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• pp.164-174
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• 1996

As tools for machining precision componants, end mills and ball end mills are widely used. For the end mills have longer cylindrical shape comparing dianeter, they are liable to deflect when machining and induce geometrical error and deterioration of surface roughness. To improve the stiffness and the sharpness of the cutting edge of end mill, a software for manufacturing end mills are developed. The program predicts the result of helical flute grinding and the configuration of cuting edge which is located in cylindrical surface. Furthermore to facilitate the manufacturing end mills using CNC grinding machine, the setting condition which satisfy the geometrical requirements like tool rake angle and stiffness are obtained.

• Annual Conference on Human and Language Technology
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• 2019.10a
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• pp.181-184
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• 2019

상호참조해결은 주어진 문서에서 상호참조해결 대상이 되는 멘션(mention)을 식별하고, 같은 개체(entity)를 의미하는 멘션을 찾아 그룹화하는 자연어처리 태스크이다. 한국어 상호참조해결에서는 멘션 탐지와 상호참조해결을 동시에 진행하는 end-to-end 모델과 포인터 네트워크 모델을 이용한 방법이 연구되었다. 구글에서 공개한 BERT 모델은 자연어처리 태스크에 적용되어 많은 성능 향상을 보였다. 본 논문에서는 한국어 상호참조해결을 위한 BERT 기반 end-to-end 신경망 모델을 제안하고, 한국어 데이터로 사전 학습된 KorBERT를 이용하고, 한국어의 구조적, 의미적 특징을 반영하기 위하여 의존구문분석 자질과 개체명 자질을 적용한다. 실험 결과, ETRI 질의응답 도메인 상호참조해결 데이터 셋에서 CoNLL F1 (DEV) 71.00%, (TEST) 69.01%의 성능을 보여 기존 연구들에 비하여 높은 성능을 보였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.11a
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• pp.1171-1172
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• 2023

자율주행 기술에서 스테레오 비전과 End-to-End Driving은 많이 사용되는 기술이며 본 연구에서는 이를 신호등 인식과 주행에 적용하였다. 신호등 인식은 좌우 카메라로부터 적색 원을 인식한 후 스테레오 비전을 통해 신호등과의 거리를 추정한다. 주행 시스템은 End-to-End Learning 기반으로 이루어지며, 출력값인 가변저항을 조향각으로 변환하여 제어할 수 있다. 또한 감마 보정을 통한 데이터 증강을 통해 빛에 대해 민감하지 않게 모델을 학습하였다. 추후 신호등 인식 시 HSV 필터가 빛에 민감한 점과 주행 시 가변저항 값이 일정하지 않은 점이 해결된다면 더욱 안정적인 시스템을 구축할 수 있을 것으로 기대된다.

• ETRI Journal
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• v.46 no.1
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• pp.48-58
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• 2024

This paper presents the development of language tutoring systems for nonnative speakers by leveraging advanced end-to-end automatic speech recognition (ASR) and proficiency evaluation. Given the frequent errors in non-native speech, high-performance spontaneous speech recognition must be applied. Our systems accurately evaluate pronunciation and speaking fluency and provide feedback on errors by relying on precise transcriptions. End-to-end ASR is implemented and enhanced by using diverse non-native speaker speech data for model training. For performance enhancement, we combine semisupervised and transfer learning techniques using labeled and unlabeled speech data. Automatic proficiency evaluation is performed by a model trained to maximize the statistical correlation between the fluency score manually determined by a human expert and a calculated fluency score. We developed an English tutoring system for Korean elementary students called EBS AI Peng-Talk and a Korean tutoring system for foreigners called KSI Korean AI Tutor. Both systems were deployed by South Korean government agencies.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.5
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• pp.349-357
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• 2003

Several microvascular anastomotic techniques have been described with methodical effectiveness, patency rates, healing state of microscopic findings. This experimental study presents the comparison of three types of arterial microvascular anastomotic techniques: end-to-end(ETE) anastomosis, end-in-end(EIE) anastomosis, and continuous technique. Sixty male Sprague-Dawley rats, 60 femoral arteries were used for this study. Twenty rats per each technique were used and sacrificed at post-operation 1 day, 3 days, a week, 2 weeks for scanning electromicroscopic findings. The patency was monitored by miniDoppler throughout total experimental periods. The anastomotic time on each method was measured to compare the technical effectiveness. The final results were as follows: 1. The anastomotic time for the end-in-end technique was significantly shorter than another techniques. The average time for each technique was measured as 15 minutes on EIE technique, 20 minutes on continuous technique and 25 minutes on ETE technique. 2. The patency rate for the end-in-end technique at 2 weeks also was superior to another techniques. The patency rate for each technique was demonstrated as 90 % on EIE technique, 85 % on ETE technique and 80 % on continuous technique. 3. The scanning electromicroscopic findings on healing condition of vessel endothelium during the observation period showed that the end results of EIE technique, ETE technique and continuous technique in sequence were good. The end-in-end technique proved to be the superior with regard to anastomotic time and patency rate when compared to end-to-end technuqe, so EIE techniqe might be well available for the case of large discrepancy of vessel size. The patency rate, microscopic healing findings in continuous technique were seen as the lowest level among the three anastomotic techniques, therefore the application of continuous technique was recommended only on the inevitable case.

• Journal of KIISE:Information Networking
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• v.35 no.5
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• pp.415-424
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• 2008

In this paper, we compare the QoS performance enhancement schemes according to the network architecture of mobile WiMAX system in order to improve the end-to-end QoS performance and propose QoS parameter mapping method and IP packet scheduling algorithm. To evaluate the end-to-end QoS performance, we implemented an end-to-end simulator of mobile WiMAX system using OPNET. Simulation results show that the proposed QoS parameter mapping scheme reduces the average delay of VoIP packet and improves uplink resource efficiency. And also, when the proposed IP packet scheduling algorithm is applied to the system, the end-to-end packet transmission delay of VoIP service can be reduced by 44-67 percent compared to FIFO and WRR scheduler.

• Journal of The Korean Society of Integrative Medicine
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• v.5 no.4
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• pp.57-66
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• 2017

Purpose : The current study objective was to determine the attitudes of nursing students to death, perception of end-of life care, and perceptions of educational training needs in relation to the provision of end-of life care, and to apply the results to the development of an efficient and effective education program in this regard. Method : Data collection was carried out between March and April 2017, and was achieved through the administration of a questionnaire to 124 caregivers working in a nursing home in C. A self-report instrument was used to measure nursing attitudes to death, perceptions of end-of-life care, and perceptions of educational training needs in relation to the provision of end-of-life care. The collected data were analyzed using SPSS(R) Statistics for Windows(R)(version 21.0), and were calculated was whole numbers, percentages, $mean{\pm}standard$ deviation, and Pearson's correlation coefficient. Results : The average scores obtained were 2.85 out of a maximum of 4.00, 2.14 out of 4.00, and 2.42 out of 4.00, for attitudes to death, perceptions of end-of-life, and perceptions of educational training needs in relation to the provision of end-of-life care, respectively. A positive correlation was found between attitudes to death and perceptions of end-of-life care, and a negative correlation was found between perceptions of end-of-life care and educational training needs in relation to the provision of end-of-life care. Conclusion : The development and implementation of an educational program is necessary to ensure positive attitudes to death in nursing students and improve their perceptions about end-of-life care. Further research is also warranted to determine the impact of such a program in this regard.

• Journal of Communications and Networks
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• v.12 no.2
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• pp.103-113
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• 2010

In this paper, a tradeoff between the total energy consumption-per-bit and the end-to-end rate under spatial reuse in wireless multi-hop network is developed and analyzed. The end-to-end rate of the network is the number of information bits transmitted (end-to-end) per channel use by any node in the network that is forwarding the data. In order to increase the bandwidth efficiency, spatial reuse is considered whereby simultaneous relay transmissions are allowed provided there is a minimum separation between such transmitters. The total energy consumption-per-bit includes the energy transmitted and the energy consumed by the receiver to process (demodulate and decoder) the received signal. The total energy consumption-per-bit is normalized by the distance between a source-destination pair in order to be consistent with a direct (single-hop) communication network. Lower bounds on this energy-bandwidth tradeoff are analyzed using convex optimization methods. For a given location of relays, it is shown that the total energy consumption-per-bit is minimized by optimally selecting the end-to-end rate. It is also demonstrated that spatial reuse can improve the bandwidth efficiency for a given total energy consumption-per-bit. However, at the rate that minimizes the total energy consumption-per-bit, spatial reuse does not provide lower energy consumption-per-bit compared to the case without spatial reuse. This is because spatial reuse requires more receiver energy consumption at a given end-to-end rate. Such degraded energy efficiency can be compensated by varying the minimum separation of hops between simultaneous transmitters. In the case of equi-spaced relays, analytical results for the energy-bandwidth tradeoff are provided and it is shown that the minimum energy consumption-per-bit decreases linearly with the end-to-end distance.