• 제목/요약/키워드: History of Technology

검색결과 2,373건 처리시간 0.033초

XLPE 절연체에서의 열이력 추정 연구 (Study on the Estimation of Thermal History in XLPE Insulation)

  • 이상진;김영호;김영성;박완기
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1999년도 하계학술대회 논문집 D
    • /
    • pp.1575-1577
    • /
    • 1999
  • XLPE is widely used as a main insulation in EHV power cables, deeply connected with thermal stress. In this study, the thermal history of XLPE insulation was examined using DSC(Differential Scanning Calorimetry). The principle is on the basis of the phenomenon that crystal in polyethylene is rearranged as it is annealed near/below the melting temperature. From the result, it was possible to define accurate temperature which was really applied on the XLPE insulation and this method was assured as a useful tool in characterization of thermal history in XLPE cable insulation.

  • PDF

불도저의 구조해석에 의한 내구성 연구 (Study on Durability by Structural Analysis of Bulldozer)

  • 한문식;조재웅
    • 한국생산제조학회지
    • /
    • 제20권3호
    • /
    • pp.239-244
    • /
    • 2011
  • This study analyzes the behaviors on stress, fatigue and vibration about bulldozer in operation. Maximum equivalent stress is shown with the frequency of 100 Hz in case of the harmonic vibration analysis applied with force. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of 0 to -105MPa and the amplitude stress of 0 to $1.617{\times}105MPa$, the possibility of maximum damage becomes 3.23%. This stress state can be shown with 5 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The structural result of this study can be effectively utilized with the design of bulldozer by investigating prevention and durability against its damage.

자전거 페달에 대한 구조 및 피로 해석 (Structural and Fatigue Analysis on Bicycle Pedal)

  • 한문식;조재웅
    • 한국생산제조학회지
    • /
    • 제21권1호
    • /
    • pp.51-57
    • /
    • 2012
  • This study investigates structural and fatigue analyses at bicycle pedal. Maximum deformation at model 1 is 2 times as much as model 2 at static analysis. Models 1 and 2 have the possibility of the weakest strength at the part of contact with chain gear. Among the cases of nonuniform fatigue loads at Models 1 and 2, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of 0 to $-10^4$ MPa and the amplitude stress of 0 to $10^4$ MPa, the possibility of maximum damage becomes 4%. This stress state can be shown with 5 to 7 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The analysis result of this study can be effectively utilized with the safe design of pedal.

불규칙 피로 하중을 받는 자동차의 컨트롤 암의 구조 해석 (Structural Analysis on Control Arm of Automobile under Nonuniform Fatigue Load)

  • 조재웅
    • 한국기계기술학회지
    • /
    • 제13권3호
    • /
    • pp.87-92
    • /
    • 2011
  • This study analyzes structural stress and fatigue on control arm of automobile under nonuniform load. Maximum equivalent stress at bolt part is shown with 419.1MPa and the corner is deformed with maximum displacement of 1.1628mm. Among 3 cases of nonuniform fatigue loads applying on control arm, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample history' with the average stress of $-10^5MPa$ to $10^5MPa$ and the amplitude stress of 0 MPa to $10^5MPa$, the possibility of maximum damage becomes 3%. This stress state can be shown with 6 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. Safety and durability on automobile can be effectively improved by applying the fatigue analysis result on control arm.

텍스트 마이닝을 활용한 건설안전사고 빅데이터 분석 (Big Data Analytics of Construction Safety Incidents Using Text Mining)

  • 서정욱;송지훈
    • 한국산업융합학회 논문집
    • /
    • 제27권3호
    • /
    • pp.581-590
    • /
    • 2024
  • This study aims to extract key topics through text mining of incident records (incident history, post-incident measures, preventive measures) from construction safety accident case data available on the public data portal. It also seeks to provide fundamental insights contributing to the establishment of manuals for disaster prevention by identifying correlations between these topics. After pre-processing the input data, we used the LDA-based topic modeling technique to derive the main topics. Consequently, we obtained five topics related to incident history, and four topics each related to post-incident measures and preventive measures. Although no dominant patterns emerged from the topic pattern analysis, the study holds significance as it provides quantitative information on the follow-up actions related to the incident history, thereby suggesting practical implications for the establishment of a preventive decision-making system through the linkage between accident history and subsequent measures for reccurrence prevention.

한의 신의료기술 행위 동향 분석 (Study on the Present Status and Developments of New Health Technologies of Traditional Korean Medicine)

  • 한창현;박황진;이봉효;이영준;권오민
    • Korean Journal of Acupuncture
    • /
    • 제29권2호
    • /
    • pp.315-326
    • /
    • 2012
  • Objectives : The new health technology assessment system was introduced in April 2007. The purpose of new health technology assessment is assessing safety and efficacy in deciding a behavior of new health technology according to the Health Insurance Act. This study aims to understand the present status of new health technologies of Korean medicine. Methods : This research introduces new health technologies and their present status, and searches for a development direction for the new health technology of Korean medicine in the future. Results : Thirty seven cases(3%) of Korean medicine doctors who utilized new health technologies application were found. In the status about new health technologies application by technologies assortment, diagnostic test techniques were used more often than treatment skills. New medical technology that included korean medicine doctor as actual user was only one item, i.e. HCV antibody test. Conclusions : In order for the new health technology of korean medicine to settle down well, continuous interest and efforts of both government and medical community are necessary.

Co-existence of History of Mathematics and Modern Mathematics

  • Banihashemi, Saied Seyed Agha
    • 한국수학교육학회:학술대회논문집
    • /
    • 한국수학교육학회 2010년도 제44회 전국수학교육연구대회
    • /
    • pp.261-267
    • /
    • 2010
  • Both history of mathematics and education of mathematics is old subject. The question arises wether can these two important subjects can help each other or not. Unfortunately this idea made mathematics society into two groups; one has idea that history of mathematics can help education of mathematics and other group has idea that not only history of mathematics can not help education of mathematics but also it makes some confusion. In this article the author is going to do some comparison and take some conclusion that history of mathematics can make education of mathematics so active and interesting.

  • PDF

한 · 중 데이터로 살펴본 직장 내 CCTV 도입 신뢰에 대한 일본 과거사의 점화효과 연구: 보안 취약성 지각의 조절된 매개 모형 (Understanding the Japanese History Problem on Trust in Technology Adoption of Workplace Surveillance Cameras: A Moderated Mediation Model in Korean and Chinese Context)

  • 최성원;장리팡;김미정;박종현
    • 아태비즈니스연구
    • /
    • 제14권4호
    • /
    • pp.49-65
    • /
    • 2023
  • Purpose - In the Korean and Chinese social landscape, it is vital to appreciate the significance of the Japanese history problem. The current study investigated whether the perception of the Japanese history problem affects decisions regarding technology adoption in organizations by comparing South Korea and China. Design/methodology/approach - The study involved 305 Korean and 379 Chinese participants who responded to scenarios and surveys regarding the adoption of workplace surveillance cameras supplied by a Japanese company. Findings - Using a moderated mediation model based on protection motivation theory (PMT), we found that past experiences of privacy invasion significantly reduced trust in the adoption of surveillance cameras at work. This relationship was mediated by respondents' perceptions of security vulnerability. The current study, however, did not confirm any significant moderating effect of the Japanese history problem priming on trust in the adoption of workplace surveillance cameras. Research implications - This suggests that the Japanese history problem may have a limited impact on organizational technology adoption decisions, different from the political consumerism behavior driven by public anti-Japanese affectivity. The current study reaffirms the validity and applicability of PMT and provides both theoretical insights and practical recommendations.

The Competitiveness Analysis of Geely Automobile Group

  • Yuhang Xia;Mingsheng Li;Junzhu Zhang;Myeongcheol Choi;Hannearl Kim
    • International Journal of Advanced Culture Technology
    • /
    • 제12권2호
    • /
    • pp.402-408
    • /
    • 2024
  • The purpose of this research is to discuss the development history and future strategy of Geely Automobile Group Co., Ltd. Founded in 1997, Geely Automotive Group has grown from a small workshop to one of China's leading automakers after nearly three decades of development.This paper first reviews the development of Geely Automobile, from the initial small-scale production to the current global layout and diversified product line. Secondly, it analyzes the challenges and opportunities faced by Geely Automobile, including the intensification of market competition and the changing demand for technological innovation.And put forward the future development strategy of Geely Automobile, including improving the quality of products, expanding the international market and promoting the development of new energy vehicles. By analyzing the development history and future strategy of Geely Automobile Group Co., Ltd., we can better understand the company's position and future development direction in China's automobile industry.

BWIM방법을 이용한 차량 정보 추정시 정밀도 향상 방안에 관한 연구 (A Study on Accuracy Improvement for Estimation of Vehicle Information Using BWIM Methodology)

  • 황효상;경갑수;이희현;전준창
    • 한국안전학회지
    • /
    • 제28권1호
    • /
    • pp.63-73
    • /
    • 2013
  • Dynamic strain history curve measured in the field is influenced by various factors such as vehicle type, speed, noise, temperature and running location etc.. Because such curve is used for vehicle weight estimation methodology suggested by Moses, exact strain history curve is the most important thing for exact estimation of vehicle weight. In this paper, effect of such factors mentioned above is investigated on the measured strain history curves, and results of weight estimation of vehicles are discussed quantitatively. From this study, it was known that temperature effect contained in the strain history curve measured for long time in-site gives the biggest effect on result of weight estimation and it can be removed by using the mode value. Furthermore, gross vehicle weight can be estimated within 5% error corresponding to A class of the European classification if effects of temperature and noise are removed and vehicle properties such as speed, axle arrangement and running location are considered properly.