• Title/Summary/Keyword: on-저항

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The Impacts of Innovation Resistance Management on Technological activities and Innovation Performance (기업의 혁신저항관리활동이 기술혁신활동과 혁신성과에 미치는 영향)

  • Ban, Jae-In;Kim, Sung-Hong
    • Journal of Korea Technology Innovation Society
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    • v.15 no.3
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    • pp.627-648
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    • 2012
  • The Purpose of current study is to empirically examine the impact of innovation resistance management practices on technological innovation activities and its performance. Drawing upon literature review, innovation resistance management practices are conceptualized and the measurement items of independent and dependent variables are developed. Survey-based data for this study was collected from 300 Korea manufacturers. The results of structural equation modeling analysis are as follows. First, innovation resistance management practices significantly affected on technological innovation activities and its performance. Second, technological innovation activities affected on its performance. Therefore, in order to make high innovation performance, corporate have to properly implement the innovation resistance management practices.

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Influence of Micro-Structural Characteristics of Concrete on Electrical Resistivity (콘크리트의 미세구조 특성이 전기저항에 미치는 영향)

  • Yoon, In-Seok
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.17 no.6
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    • pp.122-129
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    • 2013
  • Since electrical resistivity of concrete can be measured in a more rapid and simple way than chloride diffusivity, it should be primarily regular quality control of the electrical resistivity of concrete which provides the basis for indirect of quality control of chloride diffusivity during concrete construction. If this is realized, the electrical resistivity of concrete can be a crucial parameter to establish maintenance strategy for marine concrete structures. The purpose of this study is to develop, design and test a surface electrical resistivity measurement protocol. Microstructural affecting factors such as capillary water, porosity, tourtousity, and so on, on the electrical resistivity of concrete were examined taking into account for mixing proportion properties, and hydration stage. This study can provide a non-destructive approach for durability design of marine concrete. From the relationship between electrical resistivity and chloride diffusivity, it is expected that the result is subsequently used as a calibration curve for an indirect control of the chloride diffusivity based on regular measurements of the electrical resistivity during concrete construction.

Study on the Damage Behavior of 304 Stainless Steel for Gas Boiler with Specific Resistance (비저항에 따른 가스보일러용 304스테인리스강재의 손상거동에 관한 연구)

  • Yun, Byoung-Du;Lim, Uh-Joh;Jeong, Ki-Cheol
    • Journal of the Korean Institute of Gas
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    • v.9 no.4 s.29
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    • pp.6-10
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    • 2005
  • This paper was studied on the damage behavior of stainless steel (STS 304) for gas boiler with specific resistance. The electrochemical polarization test of STS304 for gas boiler was carried out. And the anodic polarization and damage aspect, such as pitting corrosion, was considered. With being low specific resistance, the passive current density of STS 304 increases, passive region and pitting potential is low. Also, the patting aspect of STS304 In specific resistance $74{\Omega}{\cdot}m$ water little appears, the pitting number increases and the damage behavior, such as pitting aspect, gradually grow bigger with being low specific resistance.

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Investigation of Coring Grounding Construction by Equivalent Radius Concept (등가반경개념에 의한 코어링 접지공사의 고찰)

  • 김세호;김일환;양문길
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.5
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    • pp.103-110
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    • 2003
  • The grounding system is necessary to provide means to dissipate electric currents into the earth without exceeding any operating and equipment limits. The ground is composed of various soils and the resistivity of the soil depends on many parameters. It depends on the type of soil and varies with distance as well as with depth. Especially, soil resistivity of volcanic area such as Jeju is ve교 high and it is difficult to acquire necessary grounding resistivity. This paper introduces the efficient grounding construction using coring technique for proper grounding resistance in high resistivity area. Because it is difficult to measure the accurate resistivity of soils, their resistivities are estimated using measured value of ground resistance and equivalent radius method. Estimated resistivities are used for grounding resistance in scheduled construction region.

A Study on the Resistance Characteristics for Planing Craft with Air Injection at the Bottom (선저 공기공급에 따른 활주형선의 저항특성 연구)

  • Park, Chung-Hwan
    • Journal of Navigation and Port Research
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    • v.36 no.3
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    • pp.157-162
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    • 2012
  • A planing craft is designed specifically to achieve comparatively high speed on the surface of the water. The frictional resistance of planing craft can be reduced further by injecting air to the craft's bottom. In this paper, the resistance characteristics of high speed planing crafts with & without air injection at the bottom were compared by sea model-test method. As a result, we conformed that planing craft with air injection has much greater the effect of resistance reduction.

Effects of the Current Probe on Ground Resistance Measurements Using Fall-of-Potential Method (전위강하법에 의한 접지저항측정에 미치는 전류보조전극의 영향)

  • 이복희;엄주홍
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.6
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    • pp.69-77
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    • 2000
  • In this paper, the effects of the positions of the potential and current probes on the measurements of the ground resistance and potential gradients with the fall-of-potential method are described and the testing techniques to minimize the measuring errors are proposed. The fall-of-potential method is theoretically based on the potential and current measuring principle and the measuring error is primarily caused by the position and ground resistance of the measuring probes. The ground resistance is calculated by applying the 61.8% and rule in the fall-of-potential method, and then the potential probe is located on the straight line between the grounding electrode to be measured and the current probe. However, sometimes the grounding electrode to be measured and the measuring probes in on-site test might not be arranged on the straight line with adequate distance because there are building, road block, construction and other establishments. Provided that the grounding electrode to be measured and the measuring probes ar out of position on the straight line or have inadequate distance, the measurement of the ground resistance classically falls into an error and the measured ground resistance should be corrected. Measurements were focused on the grounding electrode system made by the ground rods of 2.4m long. It was found that the suitable separation between the grounding electrode to be measured and the current probe is more than 5 times of the length of the grounding electrode to be measured.

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Inheritance of Resistance to Bacterial Spot and to Phytophthora Blight in Pepper (고추의 더뎅이병(病) 저항성(抵抗性)과 역병(疫病) 저항성(抵抗性)의 유전(遺傳))

  • Kim, Byung Soo;Kwon, Young Seok;Shon, Eun Young
    • Current Research on Agriculture and Life Sciences
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    • v.9
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    • pp.127-133
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    • 1991
  • PI201232, a pepper line resistant to Phytophthora capsici Leonian, was crossed with PI2713222 and P1163192, resistant to Xanthomonas campestTis pv. vesicatoria (Doidge) Dye and inheritance of the resistance to each disease and genetic relationship between the two disease resistances was studied. Non-hypersensitive resistance to race 3 of X. c. pv. vesicatoria of PI271322 was inherited in a quantitative mode. Resitance to P. capsici of PI201232 was inherited in a mode close to two dominant alleles. Hypersensitive resistance to race 1 of X. c. pv. vesicatoria of PI271322 was inherited in a mode of single dominant allele. PI 163192 was consistently resistant to both race 1 and race 3 of X c. pv. vesicatoria and the resistance was inherited in a quantitative mode with high dominance effect. Resistance to X. c. pv. vesicatoria was inherited independently from resistance to P. capsici.

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Three-Dimensional Subsurface Resistivity Profile using Electrical Resistance Tomography for Designing Grounding Grid (접지 그리드 설계를 위한 전기 저항 단층촬영법에 기반한 지표의 3차원 저항률 분포 추정)

  • Khambampati, Anil Kumar;Kim, Kyung Youn
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.4
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    • pp.117-128
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    • 2016
  • Installation of earth grounding system is essential to ensure personnel safety and correct operation of electrical equipment. Earth parameters, especially, soil resistivity has to be determined in designing an efficient earth grounding system. The most common applied technique to measure soil resistance is Wenner four-point method. Implementation of this method is expensive, time consuming and cumbersome as large set of measurements with variable electrode spacing are required to obtain a one dimensional resistivity plot. It is advantageous to have a method which is of low cost and provides fast measurements. In this perspective, electrical resistance tomography (ERT) is applied to estimate subsurface resistivity profile. Electrical resistance tomograms characterize the soil resistivity distribution based on the measurements from electrodes placed in the region of interest. The nonlinear ill-posed inverse problem is solved using iterated Gauss-Newton method with Tikhonov regularization. Through extensive numerical simulations, it is found that ERT offers promising performance in estimating the three-dimensional soil resistivity distribution.

Analysis of Geophysical and Geotechnical SPT Data for the Safety Evaluation of Fill Dam (필댐 안정성 평가를 위한 물리탐사와 SPT 자료의 분석)

  • Oh, Seok-hoon;Sun, Chang-Guk
    • Journal of the Korean Geophysical Society
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    • v.7 no.3
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    • pp.171-183
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    • 2004
  • Electrical resistivity survey is widely used to investigate the stability of center-core type fill dam against the seepage phenomenon. In this study, we analyze the resistivity information obtained on a earth fill dam and compare it with the geotechnical SPT result. The analysis shows that the zones showing low resistivity value generally have low N value. However, some zones with high resistivity pattern do not accompany the increase of N value, and even showing low N value. These results imply that the direct identification of resistivity value to the real status of the core material of fill dam is impossible, and a highly resistive zone may be in serious status due to the effect increasing the resistivity value by the piping condition. Therefore, multiple exploration should be planned to reduce the uncertainty in application of geophysical methods to dam safety evaluation.

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Study on the Added Resistance of Barge in Waves (부선의 파랑중 저항 증가에 관한 연구)

  • Ahn, Byung-Kil;Lee, Sang-Min
    • Journal of Navigation and Port Research
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    • v.34 no.10
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    • pp.741-746
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    • 2010
  • It is necessary to estimate more accurately the resistance of barge in still water and waves to compute the break load of towline and towing power for safety towing performance. The method proposed by government has calculated the total resistance of barge which is composed of frictional resistance, wave making resistance and air resistance considering the shape of hull and towing speed. However, the added resistance is equally applied with the significant wave height regardless of the type of vessels. In this study, we have carried out the numerical calculation to estimate the added resistance of wigley model in waves and compared with the experiment data to confirm the accuracy of the method. Then the computation was executed for the barge varying shape of the bow. As a result, added resistance of barge was differently occurred i.e. 0.3∼1.1 ton according to encounter angle, 0.4∼1.2 ton according to towing speed and 0.5∼1.1 ton according to shape of bow.