• 제목/요약/키워드: tool change

검색결과 1,870건 처리시간 0.03초

5축 가공에 의한 SCM415 롤러 캠 개발과 표면조도 연구 (A Study on the Development and Surface Roughness of Roller Cam SCM415 by 5-Axis Machining)

  • 김진수;이동섭;강성기
    • 한국정밀공학회지
    • /
    • 제30권4호
    • /
    • pp.397-402
    • /
    • 2013
  • In this study, we carried out the each lines of section, using GC (green silicon carbide) whetstone, the SCM415 material which separated by after and before heat treatments process, in 3+2 axis machining centers for integrated grinding after cutting end mill works, the spindle speed 8000 rpm and feed rate 150 mm/min. For the analysis of the centerline average roughness (Ra), we measured by 10 steps stages. Using Finite element analysis, we found the result of the load analysis effect of the assembly parts, when applied the 11 kg's load on both side of the ATC (Automatic tool change) arm. The result is as follows. For the centerline average roughness (Ra) in the non-heat treatment work pieces, are appeared the most favorable in the tenth section are $0.510{\mu}m$, that were shown in the near the straight line section which is the smallest deformation of curve. In addition, the bad surface roughness appears on the path is to long by changing angle, the more inclined depth of cut, because the chip discharging is not smoothly.

안면신경마비 환자의 예후 평가 도구로서의 적외선 체열 촬영(DITI - Digital Infrared Thermographic Imaging) 가능성에 대한 연구 (Study on the possibility of Digital Infrared Thermographic Imaging as a prognosis evaluation tool for patients with facial palsy)

  • 배효빈;고우신;윤화정
    • 한방안이비인후피부과학회지
    • /
    • 제30권3호
    • /
    • pp.62-75
    • /
    • 2017
  • Objectives : The aim of this study is to evaluate possibility of DITI as prognosis evaluation tool of facial palsy. Methods : We investigate prognosis of facial palsy through EMR(Electronic Medical Record) of inpatient from December 2016 to June 2017. We evaluated the sex, age distribution, length of hospital stay, paralysis site, number of treatment after discharge, change of H-B Grade at entrance and exit, temperature difference of both sides of DITI, and Nerve Conduction Study(NCS) with reference to EMR recorded symptom change. Results : 1. Significant correlations were not found between DITI and House-Brackmann Grade change, NCS(%), the date of admission. 2. There was a negative correlation between NCS(%) and hospitalization period in patients with facial palsy. The higher the NCS, the faster the recovery rate of facial palsy. 3. In patients with facial palsy, the temperature difference between the two sides after the DITI image shows that the affected side tends to be lower than the normal side. Conclusions : In this study, only DITI temperature difference between both sides of face is not significant in determining the prognosis of facial palsy. Further research is needed to conduct DITI at the same time and to improve accuracy through a sufficient assessment of the degree of facial palsy.

과학교육 관련 자기이해와 변화역량 조사 도구 개발 및 적용 -초등예비교사의 인식을 중심으로- (Development and Application of Questionnaire for Self-Understanding and Change Capacity Related to Science Education: Focus on the Recognition of Pre-Service Elementary Teachers)

  • 조광희;정용재;최재혁;김희경
    • 한국과학교육학회지
    • /
    • 제38권6호
    • /
    • pp.901-917
    • /
    • 2018
  • 본 연구는 초등예비교사들을 대상으로 과학교육 관련 자기이해와 변화역량에 대한 인식 조사 도구를 개발하고, 이를 활용하여 초등예비교사들이 가지고 있는 자기이해와 자신의 변화역량에 대한 인식을 조사하는 것을 목적으로 하였다. 먼저 선행 연구 검토와 토론 등을 거쳐 초등예비교사들의 자기이해와 변화역량에 대한 인식 조사 도구를 제작하였다. 설문지의 전반부는 자기이해와 관련되는데 '자기개념 명료성', '진로정체성', '자기효능감'을 요인으로 하여, '초등예비교사로서의 자기이해'(12개 문항)와 '초등과학예비교사로서의 자기이해'(12개 문항)에 대한 내용으로 구성하였다. 설문지의 후반부는 '변화감수성', '목표의식', '협력', '성찰', '숙달'을 요인으로 하는 변화역량에 관한 내용으로, '일반적인 변화역량'(17개 문항)과 '초등예비교사로서의 변화역량'(17개 문항), '초등과학예비교사로서의 변화역량'(17개 문항)에 대하여 각각 인식 조사 문항을 작성하였다. 이 조사 도구를 사용하여 153명의 초등예비교사들을 대상으로 자기이해와 변화역량에 대한 인식을 조사한 결과는 다음과 같다. 첫째, 초등예비교사들은 자기이해와 변화역량에 대해 대체로 긍정적인 인식을 가지고 있었지만 초등과학예비교사로서의 자기이해와 변화역량에 대한 인식은 상대적으로 덜 긍정적이었다. 둘째, 초등과학예비교사로서의 자기 이해와 변화역량 요인들은 대체로 유의미한 상관을 가지고 있었으며, 특히 자기이해의 '자기효능감'과 변화역량의 '목표의식', '숙달' 사이에 높은 상관이 있었다. 이러한 결과를 바탕으로 자기이해와 변화역량 관련 과학 교육을 위한 몇 가지 시사점에 대해 논의하였다.

사회후생함수를 중심으로 한 기후경제통합-지역평가모형 비교분석 (Comparative Analysis of Regional Integrated Assessment Models of Climate and the Economy)

  • 황인창
    • 자원ㆍ환경경제연구
    • /
    • 제25권1호
    • /
    • pp.27-60
    • /
    • 2016
  • 기후경제통합평가모형(Integrated assessment model of climate and the economy)은 기후변화에 관한 경제 분석과 정책제안을 위한 필수적인 도구가 되어왔다. 최근에는 기후변화에 대응하기 위한 정책적 노력들이 대부분 국가 또는 지역 수준에서 일어난다는 인식 하에 국가 또는 지역에서의 기후변화 영향과 정책수단의 효과를 평가할 수 있는 기후경제통합-지역평가모형(Regional integrated assessment model of climate and the economy)의 중요성이 더욱 커지고 있다. 이 논문에서는 국내에서 기후경제통합-지역평가모형을 개발하기 위한 첫 번째 단계로서 사회후생함수를 중심으로 기후경제통합-지역평가모형을 이론적으로 유형화했으며, RICE(Regional integrated climate-economy model) 모형을 통해 기후변화 대응전략에 따른 국가별 기후변화정책의 변화를 수치적으로 살펴보았다. 변화하는 국제 상황, 새롭게 드러나는 과학적 증거, 국내 여건 등을 모두 반영한 기후변화정책을 수립하기 위해서는 이를 분석할 수 있는 효과적인 도구를 갖추고 있어야 한다. 이 논문에서 살펴본 기후경제통합-지역평가모형은 이를 위한 유용한 도구가 될 수 있다.

열연강판의 드릴링시 공구의 이상상태 검출에 관한 연구 (A Study on the Detection of the Abnormal Tool State in Drilling of Hot-rolled High Strength Steel)

  • 신형곤;김민호;김태영
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2000년도 추계학술대회 논문집
    • /
    • pp.888-891
    • /
    • 2000
  • Drilling is one of the most important operations in machining industry and usually the most efficient and economical method of cutting a hole in metal. From automobile parts to aircraft components, almost every manufactured product requires that holes are to be drilled for the purpose of assembly, creation of fluid passages, and so on. It is therefore desirable to monitor drill wear and hole quality changes during the hole drilling process. One important aspect in controlling the drilling process is drill wear status monitoring. With the monitoring, we may decide on optimal timing for tool change. The necessity of the detection of tool wear, fracture and the abnormal tool state has been emphasized in the machining process. Accordingly, this paper deals with the cutting characteristics of the hot-rolled high strength steels using common HSS drill. The performance variables include drill wear data obtained from drilling experiments conducted on the workpiece. The results are obtained from monitoring of the cutting force and Acoustic Emission (AE) signals, and from the detection of the abnormal tool state with the computer vision system.

  • PDF

Shear Process and Frictional Characteristics in Down-end Milling

  • Lee, Young-Moon;Jang, Seung-Il
    • International Journal of Precision Engineering and Manufacturing
    • /
    • 제4권4호
    • /
    • pp.19-24
    • /
    • 2003
  • In end milling process, which is characterized by the use of a rotating tool, the undeformed chip thickness varies periodically with phase change of the tool. Although many efforts have concentrated on the study of end milling process, the analysis of shear and chip-tool friction behaviors has not been reported. Recently, a model has been proposed to simulate the shear and friction characteristics of an up-end milling process in terms of the equivalent oblique cutting. In the current study, the varying undeformed chip thickness and the cutting forces in a down-end milling process are replaced with the equivalent ones of oblique cutting. Then it is possible to simulate the shear and the chip-tool friction characteristics of a down-end milling process. The proposed model has been verified through two sets of cutting tests i.e., down-end milling and the equivalent oblique cutting tests. The experimental results show that the proposed model is suitable to analyze the shear and chip-tool frictional characteristics of down-end milling process. The specific cutting energy decreases with increase in equivalent undeformed chip thickness in a down-end milling process.

VESTAP 기반 기후변화 취약성 평가 지침 (Guidelines for the VESTAP-based Climate Change Vulnerability Assessment)

  • 박두선;박보영;정은화
    • 한국기후변화학회지
    • /
    • 제8권4호
    • /
    • pp.339-346
    • /
    • 2017
  • The Korea Adaptation Center for Climate Change (KACCC) located in Korea Environment Institute has serviced a climate change vulnerability assessment support tool (VESTAP) since 2014 in order to help local governments to establish their own adaptation plans. Owing to its easy usage, the VESTAP has been utilized by not only local governments but also academia for examination of climate change vulnerability in various fields. However, the KACCC has not suggested a standard usage how to compose indices for climate exposure, sensitivity, and adaptation capacity which are main components of vulnerability although the KACCC manages operation and application of the VESTAP. Many users had no choice but to compose indices based on their own interpretation on the components of vulnerability. This technical note suggests the standard usage of VESTAP by reevaluating some vulnerability assessments previously developed. This may help users to correctly compose indices for climate change vulnerability assessment, and may minimize possibility of inter-user inconsistency in definition of vulnerability assessments.

기후 변화에 따른 청미천 유역의 수질 변화 및 저감 대책에 관한 연구 (Effects of climate change and reduction method on water quality in Cheongmicheon watershed)

  • 변지선;손민우
    • 한국수자원학회논문집
    • /
    • 제51권7호
    • /
    • pp.585-597
    • /
    • 2018
  • 본 연구는 미래기후변화에 따른 청미천 유역의 향후 수질 변화를 검토하고, 최적관리기법으로의 접근을 이용한 비점오염물질 저감 대책의 유효성을 살펴보는 것을 목적으로 수행되었다. 기후변화에 따른 미래 수문 및 수질변수의 변화를 살펴보기 위하여 Soil and Water Assessment Tool(SWAT) 모형을 이용하였으며, SWAT 모형의 매개변수는 SWAT-CUP을 이용하여 보정하였다. 구축된 Representative Concentration Pathway(RCP) 시나리오 중 RCP 4.5 및 8.5 두 개 시나리오를 이용하여 미래 기후를 고려하였다. 모의 결과로부터 기후 변화가 심화될수록 강우 및 비점오염물질의 유출이 증가하는 것으로 예측되었다. 또한 적절한 최적관리기법을 통해 비점오염물질의 총량뿐만 아니라 시간에 따른 변동성도 함께 효과적으로 저감될 수 있는 것으로 판단된다.

한국어판 기후 건강관련 간호사 인지행동 측정도구의 타당도와 신뢰도 (Validity and Reliability of the Korean Version of the Climate, Health, and Nursing Tool)

  • 정다운;김광숙;박민경
    • 대한간호학회지
    • /
    • 제52권2호
    • /
    • pp.173-186
    • /
    • 2022
  • Purpose: Climate change has various negative effects on human health, which has resulted in increased burden on the health care system. Nurses contribute significantly to assessing climate-related health risks and creating a healthy environment. This study aimed to evaluate the reliability and validity of the Korean version of the Climate, Health, and Nursing Tool (K-CHANT) to measure nurses' awareness, motivation, concern, and behaviors at work and at home regarding climate change and health. Methods: The 22 items of English CHANT were translated into Korean with forward-backward translation techniques. Internal consistency reliability, test-retest reliability, and construct validity using confirmatory factor analysis were performed using SPSS WIN (25.0) and AMOS (26.0). Survey data were collected from 220 master's, doctoral, and post-doctoral nursing students. Results: The K-CHANT consists of 20 items across 5 domains. Two items of the original CHANT were excluded because of low content validity index and standardized regression weights. The internal consistency reliability of the K-CHANT, assessed by Cronbach's α was .81, with an intraclass correlation coefficient of .66~.90. The five subscales model was validated by confirmatory factor analysis (SRMR < .08, RMSEA < .08, AGFI > .70, CFI > .70). Conclusion: The K-CHANT has satisfactory construct validity and reliability to measure nurses' awareness, motivation, concern, and behaviors at work and at home regarding climate change and health. Future research should examine nurses' perceptions and behaviors related to the health effects of climate change and develop an action plan to improve it.

Requirement Analysis and Optimal Design of an Operational Change Detection Software

  • Lee, Young-Ran;Bang, Ki-In;Shin, Dong-Seok;Jeong, Soo;Kim, Kyung-Ok
    • 대한원격탐사학회지
    • /
    • 제20권3호
    • /
    • pp.189-196
    • /
    • 2004
  • This paper describes what an operational change detection tool requires and the software which was designed and developed according to the requirements. The top requirement for the application of the software to operational change detection was identified: minimization of false detections, missing detections and operational cost. In order to meet such a requirement, the software was designed with the concept that the ultimate decision and isolation of changes must be performed manually by visual interpretation and all automatic algorithms and/or visualization techniques must be defined as support functions. In addition, the modular structure of the proposed software enables the addition of a new support function with the minimum development cost and minimum change of the operational environment.