• 제목/요약/키워드: Resistance change

검색결과 2,407건 처리시간 0.033초

건축물 바닥재의 마모에 따른 미끄럼성능 변동에 관한 연구 (A Study on the Change of Slipperiness of Building Floor-coverings by Friction Wear)

  • 신윤호;최수경
    • 한국건축시공학회지
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    • 제5권1호
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    • pp.53-61
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    • 2005
  • The purpose of this study presents useful data on the choice or development of floor covering from slip viewpoint by examining closely the impact of the changes in sliding experiments due to the wear of floor covering by walk. The result of wear practical test per ten thousand walks enforces some kind of popular floor covering and measure of coefficient of slip resistance as follows: (1) When surface of floor covering is in the state of wet, the degree of wear doesn't affect greatly in slip. (2) When surface of floor covering is in dry and clean state, most floor coverings have the tendency to lower the coefficient of slip resistance with the amount of walk on it. (3) Change in the tendency of slip resistance by wear appeared mainly due to the differences in the state of floor covering and organic floor covering appeared to have great reduction of coefficient of slip resistance than the inorganic ones. (4) According to the result of investigation on changes in tendency of coefficient of slip resistance due to the increase in the number of walk and if two hundred thousand walks were done, regardless of surface shape or kind of site, etc, the safety of floor covering, in slip viewpoint, greatly reduces.

조류 흐름을 고려한 해양지반 수리저항성능 실험기 개발 (Development of Apparatus for Measuring Hydraulic Resistance of Sea Ground Considering Tidal Current Flow)

  • 강경오;정현철;김영상
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.1366-1369
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    • 2010
  • Along with the increasing need of sea development, the hydraulic stability of seabed structure on a soft seafloor ground is becoming an issue in the course of seaside development recently. However, the movement and hydraulic resistance or hydraulic stability of seafloor ground are mutually coupled with various phenomena, and there has been no clear proof for the issue, which makes it difficult to forecast. Furthermore, most researches are focused on hydraulic variables and the conditions of marine external force, while there have been few researches into the assessment in consideration of the type of a seafloor ground and the geotechnical characteristics. In addition, according to the periodic change of the flow direction, possible changes in hydraulic resistance performance of the seafloor deserves all the recognition. But there is no way to measure the hydraulic unstability of the sea ground due to tidal flow quantitatively. In this study, conventional hydraulic resistance measurement apparatus was improved to consider direction change of the current flow. Various artificial clayey soil specimens were made from Kaolinite and Jumunjin standard sand and hydraulic resistance tests were performed by changing the flow direction to validate the effect of the direction change on the scour of the seafloor.

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Damage Monitoring of CP-GFRP/GFRP Composites by Measuring Electrical Resistance

  • Shin, Soon-Gi;Kwon, Yong-Jung
    • 한국재료학회지
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    • 제20권3호
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    • pp.148-154
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    • 2010
  • It is necessary to develop new methods to prevent catastrophic failure of structural material in order to avoid accidents and conserve natural and energy resources. Design of intelligent materials with a self-diagnosing function to prevent fatal fracture of structural materials was achieved by smart composites consisting of carbon fiber tows or carbon powders with a small value of ultimate elongation and glass fiber tows with a large value of ultimate elongation. The changes in electrical resistance of CF-GFRP/GFRP (carbon fiber and glass fiber-reinforced plastics/glass fiber-reinforced plastics) composites increased abruptly with increasing strain, and a tremendous change was seen at the transition point where carbon fiber tows were broken. Therefore, the composites were not to monitor damage from the early stage. On the other hand, the change in electrical resistance of CP-GFRP/GFRP (carbon powder dispersed in glass fiber-reinforced plastics/glass fiber-reinforced plastics) composites increased almost linearly in proportion to strain. CP-GFRP/GFRP composites are superior to CF-GFRP/GFRP composites in terms of their capability to monitor damage by measuring change in electrical resistance from the early stage of damage. However, the former was inferior to the latter as an application because of the difficulties of mass production and high cost. A method based on monitoring damage by measuring changes in the electrical resistance of structural materials is promising for improved reliability of the material.

Enhancing Inoculation in the Spiral of Silence to Promote Resistance to Attacks: Examining Public Opinion on Taiwan-PRC Relations

  • Lin, Wayne Wei Kuo
    • Asian Journal for Public Opinion Research
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    • 제10권3호
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    • pp.149-177
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    • 2022
  • This study analyzes how inoculation affects the spiral of silence. Inoculation could be a beneficial tool in a democracy as it elevates citizens' resistance to attitude change "forced" by "the winning opinion" in the spiral of silence on a certain controversial issue. The study examines essential variables combined with the theories of inoculation and spiral of silence, such as resistance to counter-attitudinal attack, fear of isolation, and issue-involvement. A two-wave field experiment was employed to assess the formation of public opinion on Taiwan's political future with the People's Republic of China. Results support that inoculation enhanced people's resistance to attitude change and decreased their fear of isolation. Individuals who are more issue-involved were also shown to be more affected by inoculation, which allowed them to resist attitude change. The decreased fear of isolation, coupled with more issue involvement, might elevate people's willingness to speak out in public. More political discussions regarding an important public issue might be expected in a democracy.

염료감응형 태양전지의 투명 전극 식각을 통한 효율 향상 연구 (A Study on the Improvement of Efficiency by Scribing Transparent Conducting Oxide of Dye-sensitized Solar Cell)

  • 서현웅;손민규;이경준;김정훈;김희제
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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    • pp.416-418
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    • 2008
  • Dye-sensitized solar cell using transparent conducting oxide as electrode has large resistance such as surface resistance, charge transportation impedance in counter electrode and electrolyte, impedance between each interface. Among that resistances, surface resistance of transparent conducting oxide is relatively large. So the change of transparency has a large effect on internal resistance of dye-sensitized solar cell. Consequently, that change cause to increase or decrease the conversion efficiency. We tried to reduce the surface resistance by laser-scribing. The active area is seperated from total transparent conducting oxide by Nd:YAG laser-scribing. As a result, we achieved the improvement of efficiency about 7% and 11% in case of $0.25cm^2$ and $1.00cm^2$ dye-sensitized solar cells.

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Effects of Contact Conditions on the Connector Electrical Resistance of Direct Current Circuits

  • Kim, Young-Tae;Sung, In-Ha;Kim, Jin-San;Kim, Dae-Eun
    • International Journal of Precision Engineering and Manufacturing
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    • 제5권3호
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    • pp.5-10
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    • 2004
  • Electric contacts serve the purpose of transmitting electric signals across two conducting components. In this paper, the effects of contact conditions such as surface roughness, oxidation, and contamination were investigated with respect to electrical resistance variation of a connector in a direct current circuit. Such change in the electrical resistance is particularly important for low power circuits. The experimental results showed that compared with the effects of contact surface scratch or oxidation, the effect of contamination on the resistance variation was the most significant. In order to minimize failure due to electrical resistance change at the contact region, proper sealing to prevent contamination from entering the interface is needed.

토양환경 변화와 접지저항의 상관관계 분석을 통한 접지 저항값 예측 연구 (Estimation of Grounding Resistance by Correlation Analysing Change Factors of Soil Resistivity and Grounding Resistance)

  • 최선규;이규영;문영호;심건보
    • KEPCO Journal on Electric Power and Energy
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    • 제6권1호
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    • pp.35-40
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    • 2020
  • The purpose of this paper is to improve the grounding point measurement method for the maintenance of the earth resistance of the distribution line. This study defines the correlation among humidity of the soil, the earth resistivity and the grounding resistance. Based on the results of the study, the grounding resistance value measurement should be limited to the location where the earth resistivity change is large, and the measurement time and cost can be greatly reduced.

압저항 가속도 센서의 압저항 변화율 분포도에 관한 연구 (The Study on Piezoresistance Change Ratio of Cantilever type Acceleration Sensor)

  • 심재준;한근조;한동섭;이성욱;김태형
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.186-189
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    • 2004
  • Sensor used by semiconductor process produced an MAP sensor and applied to several industry. Among those sensors divided as transducer which convert physical quantity into electrical value, piezoresistive type sensor has been studied for the properties and sensitivity of piezoresistor. In this paper, the variation of seismic mass which have been functioned as actuator moving the cantilever beam analyzed the effect on distribution of resistance change ratio and supposed the optimal shape and position of piezoresistor. The resulting are following; According to the increment of seismic mass size, the value of resistance change ratio decreased caused by improve the stiffness. Y directional piezoresistor is formed in spot of 100 m apart from cantilever edge and length of that is 800$\mu$m. To increase the sensitivity, piezoresistor is made as n-type and x-direction.

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분기부(分岐部) 장대(長大)레일화시의 축력거동특성(軸力擧動特性) 해석(解析) (The Parameter Study on the Characteristics of Axial Force in Turnout with Continuous Welded Rail)

  • 김두환;고상훈
    • 한국구조물진단유지관리공학회 논문집
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    • 제5권2호
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    • pp.163-174
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    • 2001
  • This paper is to study the characteristics of axial force behavior that operates to the part of turnout when it makes the turnout and the continuous welded rail unifying. The study is to model by using the 50kgN rail No. 15 turnout used in the domestic national railway and the UIC60 rail No. 18 turnout used in the rapid transit railway as the finite elements for analyzing the axial force behavior of the turnout by the continuous welded rail. It is to analyze the characteristics of behavior according to the change of creep resistance, ballast resistance and the change of parameter valuables of heel joint by the axial force simulation in making the continuous welded rail and then, it is to present the result. As the result of research on the parameter valuables through the analysis, it shows that the maximum axial force of turnout by the continuous welded rail are largely subordinated to the maximum resistance of heel joint and the fitting devices than the ballast resistance. Also it shows that the maximum axial force produced changes a lot according to the characteristics of creep resistance of the fitting part and the ballast resistance.

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고유수용성신경근촉진법의 변화와 발전 (Change and Development of Proprioceptive Neuromuscular Facilitation)

  • 배성수;이현옥;구봉오;김상수;김태윤;황성수
    • PNF and Movement
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    • 제1권1호
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    • pp.27-32
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    • 2003
  • Objectives : The purpose of this study was conducted to find change and development of the proprioceptive neuromuscular facilitation(PNF). Methods: This is a literature study with books, seminar and book for the international courses. Results: Combination of isotonic has been started by Mr and Mrs Johnson after Miss Knott passed away. It is that the terms of maximum resistance changed into optimal or appropriate resistance. It is focus on activities. Maximum resistance focus not only activities but also irradiation have to fit with normal functions. PNF has enough for the motor control concepts and international classification of functioning(ICF)of WHO. Conclusions: PNF has changed and developed with giving resistance method. It is that changed from maximal resistance to optimal resistance. But it is smaller concept than maximum resistance. Even though PNF founded 60 years ago, it is enough for new concepts that is motor control and learning.

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