http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Design analysis and simulation of an external helical gear
이철희,양진룽,이강희,이철희 사단법인 유공압건설기계학회 2023 드라이브·컨트롤 Vol.20 No.4
This study optimized the parameters of the helical gear based on the original external meshing helical gear pump, combined with the analysis of the stability and flow of the basic parameters of the equipment; herringbone gears were used to eliminate the axial force generated by the helical gears. An optimized helical gear rotor was built with NX. The error between the simulation and calculation results of pump displacement was 3.95% and the simulation results were valid. Analysis of the outlet pressure and lift changes (maximum change rates of 0.38% and 0.25%), pressure analysis of the XY center plane at different times in the same cycle (no pressure surge or drop), and analysis of the axial force of the primary and driven rotors (axis The axial force is close to 0) were performed. The results showed that the flow pulsation of the external gear pump was slight, the operation was smooth, vibration and friction were reduced, the wear of bearings and other components could be diminished, and the service life of the equipment was extended. The simulation results showed that the external gear pump met the design requirements.
Reliable Fault Diagnosis Method Based on An Optimized Deep Belief Network for Gearbox
이철희,Oybek Eraliev,Ozodbek Xakimov,이철희 사단법인 유공압건설기계학회 2023 드라이브·컨트롤 Vol.20 No.4
High and intermittent loading cycles induce fatigue damage to transmission components, resulting in premature gearbox failure. To identify gearbox defects, numerous vibration-based diagnostics techniques, using several artificial intelligence (AI) algorithms, have recently been presented. In this paper, an optimized deep belief network (DBN) model for gearbox problem diagnosis was designed based on time-frequency visual pattern identification. To optimize the hyperparameters of the model, a particle swarm optimization (PSO) approach was integrated into the DBN. The proposed model was tested on two gearbox datasets: a wind turbine gearbox and an experimental gearbox. The optimized DBN model demonstrated strong and robust performance in classification accuracy. In addition, the accuracy of the generated datasets was compared using traditional ML and DL algorithms. Furthermore, the proposed model was evaluated on different partitions of the dataset. The results showed that, even with a small amount of sample data, the optimized DBN model achieved high accuracy in diagnosis
주파수대역 검출센서를 이용한 전력케이블의 부분방전 진단 시스템
이철희,최형기,홍수미,정의붕,박기영,Lee, Chul-hee,Choi, Hyung-ki,Hong, Soo-mi,Jeoung, Eui-bung,Park, Kee-Young The Institute of Electronics and Information Engin 2017 전자공학회논문지 Vol.27 No.9
본 논문은 주파수대역검출센서(FBDS)를 이용하여 전력 케이블에서 부분방전(PD)가 발생했을 때 이것을 검출하고 진단하는 시스템 개발에 관한 논문이다. 주파수대역검출센서는 각 주파수대역에서 발생하는 부분방전을 음향학적으로 변환하여 검출한다. 부분방전은 그 음향학적 신호 형태로 잡음과 유사하다. 따라서 본 논문에서 상대적 레벨교차율(RLCR)과 주파수에너지 스펙트럼을 이용하여 정상과 비정상을 구별하여 부분방전을 검출하였다. This system is a diagnosis system that checks whether it causes a partial discharge of a power cable or not. PD(Partial Discharge) is detected by FBDS(Frequency Band Detection Sensor). That is, it means a acoustic sensor capable of detecting each frequency band. The wave shape of PD sound is similar to noise and is systematically generated by partial discharge. Therefore, in this paper, we could discriminate between normal and abnormal case using relative level crossing rate(RLCR) and spectrogram of frequency energy rate.
한국 자생식물의 조직배양시 기관발생과 캘루스 형성에 미치는 몇가지 영향
이철희 충북대학교 한국과학재단 지정 첨단원예기술개발 연구센터 1997 연구보고서 Vol.2 No.-
This study was conducted to develop in vitro breeding protocols of Korean native plants, such as Gentiana scabra var. buergeri; Sedum kamtschaticum, S. aizoon; Liparis kumokiri, Pinellia ternata; Primula sieboldii; Pulsatilla koreana; Lilium miquelianum, L. amabile, L. longiflorum, L. lancifolium; Viola chaerophylloides, V. albida, V. variegata, V. variegata var. chinensis, V. patrini, V. veracunda, V. mandshurica line A-1, B-3, C-7, D-5, E-2, F-9, V. yedoensis line M-1, M-2, V. seoulensis, V. phalacrocarpa, V. ishidoyana. At least one optimal plant material and method for callus formation and shoot regeneration per species was established. These results provided the necessary baseline information for the development of in vitro breeding strategies of each species studied.
이철희 한국박물관학회 2010 博物館學報 Vol.- No.18·19
오늘날 박물관의 역할과 기능의 점점 중요해지면서 박물관에 대한 기대와 요구 또한 높아가 고 있다. 문화자원봉사 영역의 한 갈래인 도슨트제도는 교육기능이 강화된 오늘날의 박물관 기 능을 보다 효과적으로 만드는 중요한 역할을 한다 . 이에 연구자는 과연 도슨트가 관람객의 만족도에 어느 정도의 영향을 끼치는가를 설문조사를 통해 실증적으로 분석해 보았다 . 그 결과 욕구충족의 경우 전반적으로 도슨트의 안내를 받은 관람객의 만족도가 높았고, 독립 표본 T-검정 결과도 서비스의 유무가 관람객의 만족도에 영향을 끼치는 것으로 나타났다. 또한 도슨트 서비스의 만족 정도와 박물관에 대한 전반적인 만족도(욕구충족, 추천여부, 재방문의 사)을 상관분석을 통해 살펴본 바도 약하지만 상관성이 있음을 알 수 있었다. 이런 결과를토대로도슨트의 모집, 교육, 활용과사기 앙양에 대하여 정책제안을하였다 . 우 선 박물관 조직원들이 도슨트의 중요성을 제대로 인식하고, 모집단계 부터 기존 봉사자의 추천 이나 퇴직 교원이나 문화단체 소속원 그리고 문화교육프로그램 참가자들을 우선하여 모집하는 것이 효과적이라는 것을 제안하였다 . 또한 체계적인 교육 프로그램 마련과 관련 대학과의 연계 풍을 통하여 책임감을 가지고 적극적으로 활동할 수 있도록 도슨트 교육 방안을 제시하였고, 안내를 받는 관람객의 만족도 제고는 물론 도슨트 자체의 만족도를 높이기 위해서 적절한 업무 분장, 전담 직원의 배치 그리고 다양한 보상체계 구축과 활동 평가의 필요성을 강조하였다.
李喆熙,李勇仁 충남대학교 자연과학연구소 1978 學術硏究誌 Vol.5 No.2
The smou game of Japan is similar to Ssirum (a kind of wrestling) of Korea. The two games are just the same in terms of the rules, the methods, the playground, and the tools, to the exclusion of the operation of the games. If we could regulate the differences of these two games, we should compare favorably with smou as a goodwill match between two countries. Camparing the former with the Batter, some differences are observed as shown in the following. As for the smou, 1. The size of the playground is small. 2, The playground is made of mud and sand. 3. The binding of mahasi in Japan is different from that of sattba in Korea. The former must be bound around a player s waist and through between his sex organ and anal region. 4. Satiba is bound on a naked body. 5. Two players operate a match apart at the beginning course. 6. The winner or loser is decided at a single match. 7. There is no tie game. 8. The match is operated without weight difference. 9. There is a professional player. 10. There are ten ranks with yokozuna highest. 11. The players attack each other from the right side.