• Title/Summary/Keyword: Characteristic change

Search Result 2,549, Processing Time 0.03 seconds

Robust Optimization Design of Overhead Crane with Constraint using the Characteristic Functions (특성함수를 이용한 제한조건이 있는 천장크레인의 강건최적설계)

  • 홍도관;최석창;안찬우
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.21 no.2
    • /
    • pp.160-167
    • /
    • 2004
  • The correlation between the object function and the design parameter is shown on this paper by using the characteristic function for the mixed result of the structural analysis, the buckling analysis and the table of orthogonal array according to the original overhead crane's dimensional change. About the above two functions, the effectiveness of design change according to the change of design parameters could be estimated. Also, the overhead crane's weight is reduced up to 10.55 percent maintaining the structural stability according to the thickness of plate.

Evaluation of Railway Trends by Railway Characteristic Factors (철도차량 특징요인에 의한 철도차량 트렌드 평가)

  • Lee, Hee-Yup;Kim, Chang-Hyun
    • Journal of the Korean Society for Railway
    • /
    • v.9 no.6 s.37
    • /
    • pp.705-710
    • /
    • 2006
  • The railway has been developed largely by the characteristic factors of the railway through change of the society and culture. The railway trends has been changing from instinctive methods to settle the mass transport of the early days, to sensitive methods to pursue the railway culture centering around human being. As dividing by period according to the changes of railway trends into the external nation, there are to analyze the development history of the railway design. Accordingly each nation (United Kingdom, Germany, France, Japan) and the style's change, to confirm the changes into the design applied in society and culture needs, and to analyze by a year in changes of the environment and the railway history from the 1800's to 2005, so there contribute in the development of railway design to present the paradigm of the future railway by analyzing the trend according to the changes of railway design and the life environment in this paper.

Robust Optimization Design of Overhead Crane with Constraint Using the Characteristic Functions

  • Hong, Do-Kwan;Choi, Seok-Chang;Ahn, Chan-Woo
    • International Journal of Precision Engineering and Manufacturing
    • /
    • v.7 no.2
    • /
    • pp.12-17
    • /
    • 2006
  • This study uses a characteristic function to explain correlations between the objective function and design variables. For the use, structural analysis and buckling analysis are carried out. the dimensional change of an original overhead crane is made based on the table of orthogonal array. For two functions or more, the effectiveness of design change can be evaluated in accordance with change in design parameters. Also, the overhead crane's weight is reduced by up to 10.55 percent while its structural stability maintained.

Development of the Automative Correction System for the Digital Over-current Relay With Distribution System (배전계통에서의 디지털 과전류 계전기 자동 정정 시스템 개발)

  • Baek, Young-Sik;Lee, Ho-Jun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.4
    • /
    • pp.677-682
    • /
    • 2007
  • In the distribution system, Change of system happens frequently. However, most of the relays are operated manually by a person or not changed when system changed. So, when fault happened, a case that relaydoes not act rapidly happens. Also, in current power system, digital relays are used because of digitization of relay. Digital relay has very many advantages than existing analog relay. One of these advantages is that communication is available and easily can make characteristic curve. If specific values are sent to a relay by communication, A relay can make suitable characteristic curve according to the value. In this paper, by using voltages and currents measured by relay, state of CB(Circuit Breaker) and these relays, SCADA(Supervisory Control And Data Acquisition) system that control and correct characteristic curve of overcurrent relay at system change by using HMI(Human Machine Interface) is proposed.

A first study of designing Practical Korean costume according to the structure of consciousness and taste (생활한복에 대한 의식구조와 선호도에 따른 디자인연구)

  • 고정민;채금석
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.23 no.5
    • /
    • pp.654-666
    • /
    • 1999
  • Korean Costume has long history and functional aesthetic value compared with the traditional costume of other contries. But nowadays korean Costume is becoming more and more distant from the people in the world wide current. To domiciliate and spread out the Practical Korean Costume which the goverment selected as CI symbol representing Korean culture in the trend of times. We investigated and analysed systemically the consciousness of customers and the details of design. This study consist of theoritical study and positive study. Theoritical study has the esthetic characteristic(structure characteristics formative characteristic and the characteristic of color) As the conciousness of people change in modern life which everything change in high speed the esthetic characteristics of Korean Costume have changed in structure.

  • PDF

Parameter and Brightness Characteristic of Antena according to Coil turns on Electrodeless Fluorescent Lamp (무전극 램프 안테나의 권선수에 따른 휘도와 파라미터 특성)

  • Yang, Jong-Kyung;Choi, Gi-Seung;Pack, Gwang-Hyeon;Choi, Yong-Sung;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
    • /
    • 2004.11a
    • /
    • pp.281-284
    • /
    • 2004
  • In Recent, it became necessary to envelope the technology about electrodeless fluorescent lamp according to demand of the electrodeless fluorescent lamp system that used higher efficiency and advantage of long-lifetime. Especially, in the electrodeless fluorescent lamp which used H-mode, efficiency of lamp is decided from matching parameter of antena and inverter So it is of the utmost importance to design antena and inverter. Therefore, this paper used a transformer principle for efficiency rising of electrodeless fluorescent lamp and interpreted an equivalent circuit, used an impedance analyzer in order to confirm a performance enhancement of lamp along design of antenna, and confirmed parameter characteristic of R, L, C, Z, Phase, Q-factor along a change of magnetic flux density. Also, this paper confirmed a luminance characteristic of electrodeless lamp along parameter change with measuring optical characteristic along a change of magnetic flux density.

  • PDF

Parameter and Brightness Characteristic Analysis of Antena for Efficiency Improvement on Electrodeless Fluorescent Lamp (무전극 램프의 효율향상을 위한 안테나의 파라미타 특성 및 휘도특성)

  • Yang, Jong-Kyung;Choi, Gi-Seung;Pack, Gwang-Hyeon;Choi, Yong-Sung;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2004.11a
    • /
    • pp.531-534
    • /
    • 2004
  • In Recent, it became necessary to develope the technology about electrodeless fluorescent lamp according to demand of the electodeless fluorescent lamp system that used higher efficiency and advantage of long-lifetime. Especially, in the electordeless fluorescent lamp which used H-mode, efficiency of lamp is decided from matching parameter of antena and inverter. So it is of the utmost importance to design antena and inverter Therefore, this paper used a transformer principle for efficiency rising of electrodeless fluorescent lamp and interpreted an equivalent circuit, used an impedance analyzer in order to confirm a performance enhancement of lamp along design of antenna, and confirmed parameter characteristic of R, L, C, Z, Q-factor along a change of magnetic flux density. Also, this paper confirmed a luminance characteristic of electordeless lamp along parameter change with measuring optical characteristic along a change of magnetic flux density

  • PDF

A NOTE ON BETTI NUMBERS AND RESOLUTIONS

  • Choi, Sang-Ki
    • Communications of the Korean Mathematical Society
    • /
    • v.12 no.4
    • /
    • pp.829-839
    • /
    • 1997
  • We study the Betti numbers, the Bass numbers and the resolution of modules under the change of rings. For modules of finite homological dimension, we study the Euler characteristic of them.

  • PDF

An Analysis of the Characteristics in Design Rainfall According to the Data Periods (자료기간에 따른 확률 강우량 변화 특성 분석)

  • Oh, Tae-Suk;Kim, Min-Seok;Moon, Young-Il;Ahn, Jae-Hyun
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.9 no.4
    • /
    • pp.115-127
    • /
    • 2009
  • Recently, Natural disasters are increasing the damage according to the influence of the abnormal climate and climate change. This study analyzed change characteristic of Design Rainfall according to the different data periods. First, 14 observatories were selected at Meteorological Administration. Second, frequency analysis carried out 5 cases by different data periods. At the results of the frequency analysis, the design rainfall could confirm the increase in most areas of Korea. Also, the change and trend analysis carried out for characteristic analysis by design rainfall and observed rainfall. The change and trend analysis of observed annual maximum rainfall did not appeared, but the change and trend analysis of design rainfall significantly appeared using statistic methods. The result of the change and trend analysis, design rainfall increased in most areas of Korea. Although, it could be the necessity for reestimating defense ability of flood, existing river systems, and new establishment of structure about the change characteristic.

The Utilization of Frequency Response Characteristic for the Detection of Change of Backlash Magnitude (백래시 크기 변화 감지를 위한 주파수응답특성의 활용)

  • Baek, Joo-Hyun
    • Journal of the Korea Society for Simulation
    • /
    • v.24 no.3
    • /
    • pp.45-54
    • /
    • 2015
  • This paper presents the influence of backlash can be greatly increased on the frequency response characteristic which is presented as the angular velocity of a motor to the motor input voltage, if the motor input voltage is adequately reduced. And, this paper verifies theoretically, analytically and experimentally the availability on the method of detecting the change of backlash magnitude by investigating on the change of the anti-resonance and resonance frequencies in the frequency response characteristic due to the change of backlash magnitude. The amount of change of anti-resonance frequency is more useful that of resonance frequency when detecting the change of backlash magnitude, because the change of anti-resonance frequency can be measured more stable. This paper also shows the sharp change of resonance frequency can be investigated when the motor input voltage is enough reduced. The work will be useful for the further research on the backlash estimation method of a servo system with a gear reducer.