• Title/Summary/Keyword: value gap

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Robust Design of an Automobile Ball Joint Considering the Worst-Case Analysis (차량용 볼조인트의 최악 조건을 고려한 강건 설계)

  • Sin, Bong-Su;Kim, Seong-Uk;Kim, Jong-Kyu;Lee, Kwon-Hee
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.16 no.1
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    • pp.102-111
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    • 2017
  • An automobile ball joint is the element for connecting the control arm and the knuckle arm, allowing rotational motion. The ball joint consists of the stud, plug, socket, and seat. These components are assembled through the caulking process that consists of plugging and spinning. In the existing research, the pull-out strength and gap stiffness were calculated, but we did not consider the uncertainties due to the numerical analysis and production. In this study, the uncertainties of material property and tolerance are considered to predict the distributions of pull-out strength and gap stiffness. Also, pull-out strength and gap stiffness are predicted as the a distribution rather than one deterministic value. Furthermore, a robust design applying the Taguchi method is suggested.

Effect of central hole on fuel temperature distribution

  • Yarmohammadi, Mehdi;Rahgoshay, Mohammad;Shirani, Amir Saied
    • Nuclear Engineering and Technology
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    • v.49 no.8
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    • pp.1629-1635
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    • 2017
  • Reliable prediction of nuclear fuel rod behavior of nuclear power reactors constitutes a basic demand for steady-state calculations, design purposes, and fuel performance assessment. Perfect design of fuel rods as the first barrier against fission product release is very important. Simulation of fuel rod performance with a code or software is one of the fuel rod design steps. In this study, a software program called MARCODE is developed in MATLAB environment that can analyze the temperature distribution, gap conductance value, and fuel and clad displacement in both solid and annular fuel rods. With a comparison of the maximum fuel temperature, fuel average temperature, fuel surface temperature, and gap conductance in solid and annular fuel, the effects of a central hole on the fuel temperature distribution are investigated.

A flow phenomenon of aquaous polymer solution in couette flow of concentric cylinder with wide circular (넓은 환상간극을 가진 동심원통속의 couette 흐름에서 고분자수용액의 유동현상)

  • 권혁칠;이성노;정진도
    • Journal of the korean Society of Automotive Engineers
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    • v.15 no.3
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    • pp.81-88
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    • 1993
  • This report describes the experimental research on the flow phenomena of the aq uaous polymer solution within the Cuette flow of the concentric, cylinders type with a wide circular gap. We have investigated the phenomena of the fluid flow through torque measuring in the system that the inner cylinder is stationary and the outer one is rotating. Geometrical parameters of the system are the gap ratio of t/R$_{0}$=0.2 and Aspect ratio of l/t=100. The torque increases considerably in about 420-480RPM, So, it is considered a turbulent transition boundary, the higher plymer concentration is, the lower torque value is and the higher transition Reynolds number is. In each of the polymer concentration, the unstable boundary of torque, that is, idiosyncrasies of torque is observed around 220-280RPM. and the boundary is looked upon as a resonant vibration which is caused by the inner cylinder and tortional vibration of torque sensor.r.

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Sound Absorbing Characteristics According to Interior Configuration of Noise Barrier (흡음형 방음벽의 내부 구성에 따른 흡음특성)

  • 박진규;김상헌;김관주;박희준
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.387-392
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    • 2003
  • This study is put a focus on the identification of sound characteristics according to the interior configuration of sound absorption material and air gap. Noise barrier is general consists of front perforated panel, air layer, sound absorption material, air gap and back plate. Noise barrier is required to the NRC value of 0.7. The absorbing performance of the noise barrier relies on the opening ratio of the perforated panel and the efficiency of the absorbing material. This study has observed the effect of opening ratio and hole size, the increase of sound absorbing performance by the configurations of sound absorption material and air gap. New designed noise barrier is achieved the acoustical performance of 0.87 the measurement in a reveration room.

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The Study on the Running Test of Urban Transit Maglev (II) - Levitation System - (도시형 자기부상열차의 주행성능시험(II) - 부상시스템 -)

  • Lee, Jeong-Seok;Lee, Seo-Woo;Kim, Bong-Seop
    • Proceedings of the KIEE Conference
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    • 1999.07a
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    • pp.6-8
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    • 1999
  • In this paper deals with running test for the UTM(Urban Transit Maglev)-01, that is test and evaluation for the maglev. We will predict about the test value for running maglev vhicle. In this time we tested rms gap fluctuation and peak to peak air gap for levitation system of UTM-01. And then we profit for the upgrade Maglev System.

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A Study on the Flow Characteristics of Rectangular Prism with Center Gap Through-flow at Different Aspect Ratio (중앙틈새를 관통하는 흐름을 갖는 사각형상 물체의 변장비에 따른 유동특성에 관한 연구)

  • Kim, Jin-Gu;Cho, Dae-Hwan;Han, Sang-Gook
    • Journal of the Korean Society of Mechanical Technology
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    • v.13 no.3
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    • pp.25-30
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    • 2011
  • Flow control of flow field is essential to design efficient elements relating to fluid machineries. In this study, flow characteristics of rectangular prism with center gap through-flow at different aspect ratio was investigated to flow control. It was used a FLUENT 6.3 version to study flow field. It was found that the through-flow disturbs the development of vertical velocity component and decreased the vortex size and critical value of a rapid change in pressure coefficient distribution.

Identifying Barriers to Big Data Analytics: Design-Reality Gap Analysis in Saudi Higher Education

  • AlMobark, Bandar Abdullah
    • International Journal of Computer Science & Network Security
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    • v.21 no.9
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    • pp.261-266
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    • 2021
  • The spread of cloud computing, digital computing, and the popular social media platforms have led to increased growth of data. That growth of data results in what is known as big data (BD), which seen as one of the most strategic resources. The analysis of these BD has allowed generating value from massive raw data that helps in making effective decisions and providing quality of service. With Vision 2030, Saudi Arabia seeks to invest in BD technologies, but many challenges and barriers have led to delays in adopting BD. This research paper aims to search in the state of Big Data Analytics (BDA) in Saudi higher education sector, identify the barriers by reviewing the literature, and then to apply the design-reality gap model to assess these barriers that prevent effective use of big data and highlights priority areas for action to accelerate the application of BD to comply with Vision 2030.

The Influence of Microwave Sintering Process on the Adaptation of CAD/CAM Zirconia Core (마이크로 웨이브 소결 과정이 CAD/CAM 지르코니아 코아의 적합도에 미치는 영향)

  • Kim, Keun Bae;Kim, Jee Hwan;Lee, Keun-Woo
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.2
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    • pp.95-107
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    • 2009
  • The purpose of this research was to examine the fitness of zirconia cores that were made by different sintering methods; generic electricity furnace and microwave furnace. Firstly, 12 cores for each group were made by using each different sintering process and attached them to a metal die with silicon. The internal and marginal gap of sintered zirconia was measured by using Skyscan 1076 micro-CT, then it was reorganized by CT-An software. To each samples, we extracted B-L image, M-D image of cutting side, and cross-sectional side of tooth long axis and calculated the mean value of marginal, axial, and occlusal gap each side. Results: 1. The mean marginal gap of sintered zirconia was $36.20{\mu}m$ for EVE, $47.67{\mu}m$ for LAV, $52.47{\mu}m$ for DEN, and $54.63{\mu}m$ for CER. 2. For the axial wall, the research showed the largest value of $63.49{\mu}m$ for EVE, but there were no statistical significance. 3. In related to the occlusal internal measurement, DEN showed the smallest value ($77.06{\mu}m$), EVE and CER showed significantly high value. From this study, it is suggested that CAD/CAM zirconia core which was made in the process of microwave sintering has clinically acceptable values in marginal and internal gap.

Korea's Participation in Global Value Chains: Measures and Implications

  • CHUNG, SUNGHOON
    • KDI Journal of Economic Policy
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    • v.38 no.4
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    • pp.45-76
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    • 2016
  • This paper measures the extent to which South Korea participated in global value chains (GVCs) from 1995 through 2011 and scrutinizes the consequences of such participation on the Korean economy. To this end, the World Input Output Database is utilized to calculate GVC income, GVC employment, and value-added exports created by Korean and foreign industries. Our findings show that Korea radically internationalized its production activities during the sample period, widening the gap between gross exports and value-added exports. We also document that Korea's participation in GVCs has changed the value-added and employment structures in domestic industries in accordance with their comparative advantages while exacerbating the degree of wage inequality.

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The Environmental, Social, and Governance (ESG) Rating, Firm Value and the Corporate Ownership Concentration

  • Heonyong Jung
    • International journal of advanced smart convergence
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    • v.12 no.3
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    • pp.157-162
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    • 2023
  • This study analyzed the relationship between ESG performance and corporate value using panel data from Chinese equipment manufacturing companies spanning from 2012 to 2021, and it also examined whether ownership structure moderates this relationship. We have contributed to filling the gap in existing research. The main conclusions of this study are as follows: Firstly, similar to previous researches, ESG performance was found to have a positive and statistically significant impact on corporate value. Secondly, when the three dimensions of ESG - Environmental (E), Social (S), and Governance (G) - were analyzed separately, it was observed that E and S have a positive and statistically significant impact on corporate value, while G has a negative and statistically significant impact. Thirdly, ownership concentration emerged as a significant moderating factor in explaining the connection between ESG performance and corporate value. Lastly, when the three dimensions of ESG were analyzed separately, ownership concentration was found to serve as a positive moderating factor in the relationship between corporate value and E and S, but it did not play a statistically significant role for G.