• Title/Summary/Keyword: Resistance value

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A Study On The Arc Resistance of $SF_6$ Gas Circuit Breaker ($SF_6$ 가스차단기의 아크저항에 관한 연구)

  • Chong, Jin-Kyo;Lee, Woo-Young;Kim, Gyu-Tak
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.9
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    • pp.1566-1570
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    • 2007
  • [ $SF_6$ ] gas circuit breakers are widely used for short circuit current interruption in EHV(Extra High Voltage) or UHV(Ultra High Voltage) power systems. To develop $SF_6$ gas circuit breakers, the arc resistance value is necessary to compare experimental results to numerical ones. The arc resistance value can be obtained from a breaking test with a $SF_6$ gas circuit breaker. The direct testing or synthetic testing facility is widely used to verify the breaking ability for $SF_6$ gas circuit breakers. We employed the simplified synthetic testing facility to test a $SF_6$ gas circuit breaker prototype. The arc resistance characteristic was measured and calculated under the various experimental conditions. This arc resistance value can be used for verifying the numerical results from arc simulation in a circuit breakers.

Estimation of Setting Time for Concrete Using CGS Fine Aggregate and Analysis of Durometer (CGS 잔골재를 사용한 콘크리트의 응결시간 추정시 듀로미터 사용 가능성 분석)

  • Lee, Hyuk-Ju;Han, Jun-Hui;Baek, Seung-Bok;Shin, Yong-Sub;Han, Min-Choel;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2019.11a
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    • pp.118-119
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    • 2019
  • In this study, we compared the proctor penetration resistance test value of the concrete using CGS for Fine Aggregate and the hardness value of the Durometer. The results are summarized as follows. 1) Surface finish The Durometer C type setting time measurement value was about 45 HD, and the hardness value of the Durometer D type was about 5HD. 2) The proctor penetration resistance test value and the hardness value of the Durometer are highly correlated and are expected to be easy to use.

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Development and Performance of Cementitious Materials for Fire Resistance of Tunnel (터널 내화용 시멘트계 재료의 개발 및 성능 평가)

  • Won, Jong Pil;Choi, Seok Won;Park, Chan Gi;Park, Hae Kyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4C
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    • pp.265-273
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    • 2006
  • This study aims at evaluation of the fire resistance performance of cementitious materials for fire protection of tunnel. For this purpose, the research procedure was divided into three parts. First, base mix proportion with different material type were determined by fire test. Second, the fire test of cementitious materials for fire resistance were performed on base mix proportions to evaluated their performance. Third, the performance of cementitious materials for fire resistance compare to the target value and existing commercial products. If the performance of developed cemetitious materials for fire resistance were satisfied the target value, this studies were stopped. But, this research return to first process if the performance of cementitious materials for fire resistance are not satisfied the target value. As a result of this study, the spalling did not happen for develop and existing commercial product. Also, developed cementitious materials for fire resistance are shown with excellent compressive strength, flexural strength, and bond strength, because it used a height density aggregate. And developed cementitious materials has sufficient resistance for fire.

Study on irradiation effect by $Co^{60}$ to the carbon resistor (탄소저항체에 대한 $Co^{60}$조사효과에 관한 연구)

  • 지철근;조성욱
    • 전기의세계
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    • v.22 no.4
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    • pp.7-10
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    • 1973
  • The characteristics of all the instruments and materials used in atomic industry is changed due to radiation damages by the effects of radiation activities. In this study, when the Carbon Resistor, main element of electrical circuits, is irradiated by Gamma-Ray, variations in its electrical properties have been investigated. The following results are obtained: 1) The resistance value in Carbon Resistor is exponentially increased as the quantity of irradiation by Gamma-Ray is increased, but in case of more than 10$^{6}$ R/hr. of quantity of irradiation it has saturated-state value. 2) The rate of change inrestistance value has been independent on the intensity of Gamma-Ray source when Carbon Resistor is irradiated in the same quantity of irradiation. 3) The resistance value in irradiated Carbon Resistor has not been varied with elapse of time. 4) The more the distance from the Carbon Resistor to the Gamma-Ray source the more greatly the resistance value is decreased and that it has been shown that the more quantity of irradiation by Gamma-Ray, the greater the rate of decrease in resistance value. Through the above results it has been concluded that the measurement values obtained by the high-precision instruments in the radiation field have to be corrected with proper consideration to radiation damages.

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Development of High-strength Cotton Fabrics for Upper of Shoes to Improve Fashionability (패션성 향상을 위한 신발갑피용 고강도 면직물 개발)

  • Lee, Jae-Ho
    • Fashion & Textile Research Journal
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    • v.21 no.2
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    • pp.203-208
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    • 2019
  • This paper considers the moisture permeability and fashion in the upper fabrics of cotton fabric shoes woven into various tissues and properties measured to examine the use as upper fabrics. We measured the tissues of the manufactured upper fabric are 1/3 twill, $4{\times}4$ weft rib, Maya, Triple, Deformed twill design (DTD), Diamond tissues and tear strength, tensile strength, breaking elongation, stretching under load at 100N, stitch tear resistance, and fastness. In the case of $4{\times}4$ weft rib, the tear strength and tensile strength were excellent; however, the elongation and stitch tear resistance at 100N load were less than the standard value. DTD fabrics are characterized by physical properties in the warp direction that are superior to those in the weft direction; however, the tear strength and tensile strength in the weft direction are less than the standard value. The 1/3 twill fabrics showed high tensile strength value and stitch tear resistance value in the warp direction; however, toughness, the main property of the shoe upper, was below the standard value. Triple and diamond fabrics, which have a significant effect on the performance of the shoe upper fabric, also had less than the standard value of tear strength. Maya upper fabric for shoes has better properties than other upper fabrics except for the elongation at break, and the stitch tear resistance has a value of 178% in the warp direction and 214% in the weft direction compared to the standard value. Therefore, the Maya fabric showed the possibility of being used as an upper textile for shoes.

A Multi-dimensional Structure for User Resistance with the Determinants of Innovative Product Use on Virtual Reality (가상현실 환경에서의 다차원적 혁신저항 구조와 혁신 제품 사용의 결정요소)

  • Park, Hyun-jung;Shin, Kyung-shik;Choi, Jaewon
    • The Journal of Society for e-Business Studies
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    • v.21 no.2
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    • pp.97-119
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    • 2016
  • Motion-sensing interface enhances the sense of reality of user experience in virtual reality context. This study analyzes the innovation resistance and adoption structure for Leap Motion, which provides a motion-sensing function, primarily considering the theory of perceived risk. Previous research regarding innovation resistance and adoption mainly addressed the resultant aspects of perceived risk, or the impact of perceived value on the adoption intention. This study synthetically reviews previous studies from a multi-dimensional view considering both resistance- and adoption-perspective. To do so, we identified important antecedents that affect perceived risk and value, and we analyzed the compound dynamics of perceived risk and value towards innovation resistance. As a result, we found that the antecedents included in the existent acceptance models from adoption-perspective can help reduce the level of perceived risk, and that higher perceived value leads to lower innovation resistance. Additionally, trialability can rather foster the perceived risk.

The Effect of Oleic Acid and Propylene Glycol on the Electrical Properties of Skin (올레인산 및 프로필렌글리콜이 피부의 전기적 성질에 미치는 영향)

  • Oh, Seaung-Youl;Guy, Richard H.
    • Journal of Pharmaceutical Investigation
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    • v.24 no.4
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    • pp.281-287
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    • 1994
  • The effects of oleic acid, propylene glycol and 5% (w/w) oleic acid in propylene glycol on the electrical properties of hairless mouse skin were studied and the results were compared. The complex electrical impedance was measured as a function of frequency, and resistance and capacitance were determined from the Nyquist plot. Immediately after the treatment with oleic acid, resistance was 145% of the pretreatment value. However it decreased with time and, after 20 hours, it was about 25% of its pretreatment value. Capacitance increased; immediately after the treatment, it was about 125% of pretreatment value and it seemed to increase slowly with time. When the skin was treated with propylene glycol, resistance decreased about 5O% and capacitance increased about 65%. Similar results were observed when the skin was treated with 5% (w/w) oleic acid in propylene glycol, except that the magnitude of resistance drop was much larger. Oleic acid acted synergistically with propylene glycol. Together with the flux data in the literature, the results obtained in this work indicate that electrical resistance is closely related to the permeability of drug molecules through the skin. The results are discussed in terms of the mechanism of action of these penetration enhancers. Overall, this work provided further mechanistic insight into the role of SC lipids in skin resistance and capacitance.

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Factors Influencing Post-Adoption Resistance to Self-Order Kiosks at Fast-Food Restaurants: A Focus on the New-Silver Generation

  • Hwaran Lee;Eunkyung Kang;Kyung Young Lee;Minwoo Lee;Sung-Byung Yang
    • Journal of Smart Tourism
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    • v.3 no.2
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    • pp.23-36
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    • 2023
  • Due to the phenomenon of aging, a new consumer segment known as the "new-silver generation" is emerging. Unlike the previous silver generation, this generation possesses significant economic power and consuming willingness, attracting attention from consumer goods companies. However, both the new-silver generation and the elderly face challenges in adopting contactless or self-service technologies such as self-order kiosks, resulting in negative reactions. Therefore, this study aims to investigate the attitude and response of the newsilver generation towards kiosks, as well as the factors influencing their resistance to such technology. By applying theoretical perspectives from the innovation resistance model, technostress theory, and the value-based model, this study identifies influencing factors for innovation resistance among the new-silver generation when using contactless technologies implemented in fast-food restaurants. The findings indicate that a lower awareness of new technologies and services corresponds to decreased adoption resistance, while a higher perceived value leads to more positive behaviors and attitudes among the new-silver generation utilizing kiosks at fast-food restaurants.

Effect of Serum Concentration on Inhibition of Nucleoside Transport by Multidrug Resistance Inhibitor BIBW22 (혈청 농도가 다제내성 억제제 BIBW22의 nucleoside 수송에 미치는 영향)

  • ;Hong-Xing Chen;Uwe Bamberger;Yung-Chi Cheng;Thomae GmbH
    • Biomolecules & Therapeutics
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    • v.3 no.2
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    • pp.116-121
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    • 1995
  • Some multidrug resistance inhibitors have been known to be influenced by the serum concentration. In this study, effect of serum concentration on inhibition of nucleoside transport by BIBW22, a new multidrug resistance inhibitor derived from dipyridamole (DPM), was studied. When 5% or 100% (v/v) of fetal bovine serum (FBS) was contained in the culture, DPM dose for which nucleoside transport was inhibited by 50% (lD$_{50}$) was 0.42 $\mu$M or 1.17 $\mu$M, respectively. BIBW22 also showed the same trend as DPM did in response to increase of FBS concentration. However, ID$_{50}$ value for DPM in the absence or presence of human plasma was 0.007 $\mu$M or 1.02 $\mu$M respectively showing 145 times increase of ID$_{50}$ value. ID$_{50}$ value for BIBW22 in the presence of human plasma was 0.028 $\mu$M showing only 5 times increase in ID$_{50}$ value. This result suggests that potency of BIBW22 was much less affected by the plasma concentration and BIBW22 could be a good candidate for a clinical use in multidrug resistance treatment.treatment.

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Analysis of Thermal Characteristics and Insulation Resistance based on Usage Environment and Current Value of Electrical Socket Outlet (전기콘센트의 사용환경과 전류값에 따른 열적특성 및 절연저항 분석)

  • Kim, Kyung Chun;Kim, Doo Hyun;Kim, Sung Chul
    • Journal of the Korean Society of Safety
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    • v.34 no.5
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    • pp.22-30
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    • 2019
  • In 2018, overload, overcurrent, insulation aging, and a contact failure caused 659 electric fires. There is almost no failure of electrical socket outlets during their manufacturing or installation period. After several months or several years, overload or overcurrent of electrical socket outlets leads to a contact failure or short circuit which causes an electric fire. Therefore, this paper analyzed for thermal characteristics based on a current value and the change in insulation resistance along with a temperature rise caused by electrical socket outlets and the state of laboratory use in workplaces. As a results, regarding the thermal characteristics based on the current value of each installation year, a temperature increase was related to a current value, an installation year, and whether the contact unit is corroded. Insulation resistance began to decrease when a temperature increased to a certain level. With a lapse of installation year, the temperature at which insulation resistance began to decrease was lowered. This paper can be applicable for the survey data about electrical socket outlet induced fire accidents and management guidelines.