• Title/Summary/Keyword: critical difference

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An AHP Approach to Select the Task Related Technique for Work Efficiency Improvement in Shipbuilding Enterprise (AHP에 의한 조선기업의 작업능률향상을 위한 과업관련기법의 선택)

  • Kim, Tae-Soo;Lee, Kang-Woo
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.30 no.2
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    • pp.67-74
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    • 2007
  • The objective of this research is to select the most effective technique among task related techniques(motion & time study, job redesign, physical environment improvement) for improving work efficiency in shipbuilding enterprise. This study consists of several principal steps. The first step is to design critical criteria in evaluating work efficiency in ship-building enterprises. The second step is to develop sub-criteria of the critical criteria. The third step is to develop a four level AHP(Analytic Hierarchy Process) structure using the critical criteria, sub-criteria and techniques among task related techniques. The fourth step is to develop the pairwise comparison matrix at each level of AHP structure, which was based on survey data collected at the H heavy industry. And the last step is to select the most effective technique among task related techniques using AHP analysis. The result of AHP analysis has shown clear difference in priority among task related techniques in terms of work efficiency of the shipbuilding enterprise: The reduction of normal time is more important than the reduction of allowance time in improving of the work efficiency. Motion & time study is the most important technique for the reduction of normal time, and physical environment improvement is the most important technique for the reduction of allowance time as well.

Firm's Economic Efficiency and Critical Weather Information in Distribution Industry by Climate Change (기후변화에 따른 유통산업의 핵심 기상요인과 기업의 경제적 효율성)

  • Lee, Joong-Woo;Ko, Kwang-Kun;Jeon, Jin-Hwan
    • Journal of Environmental Science International
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    • v.19 no.6
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    • pp.787-797
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    • 2010
  • Nowadays meteorological information is systemized as a useful knowledge which has a significant effect on the overall industrial domains over the simple data. The distribution industry, which has the short life cycle, depends on the meteorological information at the strategic level. However, it is necessary to pay attention to the continuous investment in meteorological information because there is a hostility to paying for a service, particularly it does not provide accurate and reliable information. Therefore, the purpose of this study is to increase the usefulness of meteorological information in the distribution industry for its economic effectiveness from the core meteorological factors. We found significant meteorological factors (temperature, precipitation, disaster) that have a critical influence on the distribution industry through the hierarchical analysis process, and their importance according to the type of distribution channels, such as department store, large-scale discount store, convenience store, and home shopping. We performed the AHP analysis with 103 survey samples by middle managers from the various distribution channels. We found that precipitation is the critical meteorological factor across the distribution industry. Based on this result, we stress the difference in the level of the meteorological information in order for the effectiveness of each type of distribution channels.

Effects of a Virtual Reality Simulation and a Blended Simulation of Care for Pediatric Patient with Asthma (천식 아동 간호에 대한 가상현실 시뮬레이션과 블렌디드 시뮬레이션 교육 효과)

  • Kim, Mikang;Kim, Sunghee;Lee, Woo Sook
    • Child Health Nursing Research
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    • v.25 no.4
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    • pp.496-506
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    • 2019
  • Purpose: The purpose of this study was to examine the effects of a virtual reality simulation and a blended simulation on nursing care for children with asthma through an evaluation of critical thinking, problem-solving processes, and clinical performance in both education groups before and after the educational intervention. Methods: The participants were 48 nursing students. The experimental group (n=22) received a blended simulation, combining a virtual reality simulation and a high-fidelity simulation, while the control group (n=26) received only a virtual reality simulation. Data were collected from February 25 to 28, 2019 and analyzed using SPSS version 25 for Windows. Results: The pretest and posttest results of each group showed statistically significant improvements in critical thinking, problem-solving processes, and clinical performance. In a comparison of the results of the two education groups, the only statistically significant difference was found for critical thinking. Conclusion: Simulation-based education in child nursing has continued to involve high-fidelity simulations that are currently run in many programs. However, incorporating a new type of blended simulation, combining a virtual reality simulation and a high-fidelity simulation, into the nursing curriculum may contribute to the further development of nursing education.

Frequency characteristics and sensitivity analysis of a size-dependent laminated nanoshell

  • Dai, Zuocai;Jiang, Zhiyong;Zhang, Liang;Habibi, Mostafa
    • Advances in nano research
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    • v.10 no.2
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    • pp.175-189
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    • 2021
  • In this article, frequency characteristics, and sensitivity analysis of a size-dependent laminated composite cylindrical nanoshell under bi-directional thermal loading using Nonlocal Strain-stress Gradient Theory (NSGT) are presented. The governing equations of the laminated composite cylindrical nanoshell in thermal environment are developed using Hamilton's principle. The thermodynamic equations of the laminated cylindrical nanoshell are obtained using First-order Shear Deformation Theory (FSDT) and Fourier-expansion based Generalized Differential Quadrature element Method (FGDQM) is implemented to solve these equations and obtain natural frequency and critical temperature of the presented model. The novelty of the current study is to consider the effects of bi-directional temperature loading and sensitivity parameter on the critical temperature and frequency characteristics of the laminated composite nanostructure. Apart from semi-numerical solution, a finite element model was presented using the finite element package to simulate the response of the laminated cylindrical shell. The results created from finite element simulation illustrates a close agreement with the semi-numerical method results. Finally, the influences of temperature difference, ply angle, length scale and nonlocal parameters on the critical temperature, sensitivity, and frequency of the laminated composite nanostructure are investigated, in details.

A Study on the Conclusion Bearing Capacity ol Polluted Soils Owing to Difference of Water Content (함수량이 다른 오염지반의 지지력 결정에 관한 연구)

  • 안종필;박상범;박경호
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.03a
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    • pp.481-488
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    • 1999
  • This study, investigates the existing theoretical backgrounds in order to examine the behavior of lateral flow owing to the plasticity of soils when unsymmetrical surcharge is worked on polluted soils by the increase of water content compares and analyzes the results measured through model tests. Unsymmetrical surcharge is increased at regular intervals to soil tank made up the polluted soils and then the amounts of settlement, lateral displacement and upheaval are observed. Critical surcharge was decided q$\sub$cr/= 3.42 C$\sub$u/ similar to those had proposed Terzaghi and JHI, and the value of ultimate capacity was decided q$\sub$ult/= 7.71 C$\sub$u/ similar to that of Tschebotarioff and JHI.

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Analysis of normal Bone propagation characteristics in a high-temperature superconducting tape (고온 초전도체 테이프의 상전도 영역 전파 특성 해석)

  • 정신근;설승윤
    • Progress in Superconductivity and Cryogenics
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    • v.3 no.1
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    • pp.11-15
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    • 2001
  • Stability of a Bi-2223/Ag tape was studied by using a numerical model considering the temperature distribution of cross-sectional area. The dynamic evolution of normal zone of a HTS tape can be shown by the developed two-dimensional Program using finite difference method. Two kinds of analyses are compared to quantify the critical disturbance energy for quenching HTS tapes. One is the length-thickness(x-r) side and the other is the length-width(x-z) side. For each case. the governing energy balance equations and corresponding boundary conditions are formulated. The results of analyses shows that the critical disturbance energies for each cases seem to be very close for considered Bi-2223/Ag tape .

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BLOOD PLASMA MINERALS AND FERTILITY OF DAIRY COWS IN CENTRAL THAILAND

  • Vijchulata, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.3
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    • pp.263-265
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    • 1995
  • Blood plasma minerals and their effects towards the fertility in 136 cows randomly selected from 26 dairy farms in central Thailand were studied. An average of 8.60 mg% Ca, 5.97 mg% P, 2.45 mg% Mg, $85.9{\mu}g%$ Cu, and $160.9{\mu}g%$ Zn in plasma was observed. Compared to the critical deficient values, 24.3, 10.3, 11.8, 28.7 and 0.0% of the surveyed cows obtained the respective elements in plasma below the standard levels. No significant difference (p >.05) in plasma concentrations of Ca, P, Mg and Zn for the low fertile (conception rate > 3) and fertile (conception rate < 3) cows was found. However, plasma Cu of the low fertile cows (averaged $77.2{\mu}g%$) was lower (p <.01) than that of the fertile ones (averaged $91.12{\mu}g%$). Additionally, it is observed that 47.1% of the cows with the low fertility problem obtained plasma Cu below the 65.0 pg% critical deficient value.

Study on Two-Dimensional Laminar Flow through a Finned Channel (박막이 부착된 채널내의 2차원 층류유동장에 대한 연구)

  • Yoon Seok-Hyun;Jeong Jae-Tack
    • Journal of computational fluids engineering
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    • v.7 no.3
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    • pp.53-59
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    • 2002
  • A two-dimensional laminar flow through a channel with a pair of symmetric vertical fins is investigated. At far up- and down-stream from the fins, the plane Poiseuille flow exists in the channel. The Stokes flow for this channel is first investigated analytically and then the other laminar flows by numerical method. For analytic method, the method of eigen function expansion and collocation method are employed. In numerical solution for laminar flows, finite difference method(FDM) is used to obtain vorticity and stream function. From the results, the streamline patterns are shown and the additional pressure drop due to the attached fins and the force exerted on the fin are calculated. It is clear that the force depends on the length of fins and Reynolds number. When the Reynolds number exceeds a critical value, the flow becomes asymmetric. This critical Reynolds number Re/sub c/ depends on the length of the fins.

QUALITY IMPROVEMENT OF VEHICLE DRIFT USING STATISTICAL SIX SIGMA TOOLS

  • PARK T. W.;SOHN H. S.
    • International Journal of Automotive Technology
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    • v.6 no.6
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    • pp.625-633
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    • 2005
  • Vehicle drift was reduced using statistical six sigma tools. The study was performed through four steps: M (measure), A (analyze), I (improve), and C (control). Step M measured the main factors which were derived from a fishbone diagram. The measurement system capabilities were analyzed and improved before measurement. Step A analyzed critical problems by examining the process capability and control chart derived from the measured values. Step I analyzed the influence of the main factors on vehicle drift using DOE (design of experiment) to derive the CTQ (critical to quality). The tire conicity and toe angle difference proved to be CTQ. This information enabled the manufacturing process related with the CTQ to be improved. The respective toe angle tolerance for the adjustment process was obtained using the Monte Carlo simulation. Step C verified and controlled the improved results through hypothesis testing and Monte Carlo simulation.

The Oscillation Characteristics of a Magneticfluid Plug in Curved Tube (곡관내 자성유체 PLUG의 진동특성)

  • Chun, U.H.;Lee, H.N.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.3 no.3
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    • pp.46-57
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    • 1995
  • The aim of the present study is to provide fundamental informations for the development of magneticfluid actuator. To achieve the aim, oscillation characteristics of the magneticfluid plug are investigated by experiment for the various length and position of the magneticfluid plug and the frequency of magnetic field. The oscillation characteristics are obtained. Amplitude, natural frequency, phase shift and damping ratio, are compared with theoretical values. From the study, the following conclusive remarks can be made. The experimental equation for the magnetic field is obtained. The critical magneticfluid length exists and its value is about 70mm. The range of the damping ratio and fluid loss coefficient obtained by experiment are 0.1~0.2 and 30~100, respectively. Comparison between experimental and theoretical results of oscillation characteristics shows good agreement in the high frequency range. Meanwhile, in the low frequency range, there appears little discrepancies(5% in the frequency and amplitude and 10% in phase difference and damping ratio) with each other.

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