• Title/Summary/Keyword: Superior

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Synthesis of Ceramic Protective Coatings for Chemical Plant Parts Operated in Hi-temperature and Corrosive/Erosive Environment

  • Son, M.C.;Park, J.R.;Hong, K.T.;Seok, H.K.
    • Corrosion Science and Technology
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    • v.4 no.1
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    • pp.33-38
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    • 2005
  • Some feasibility studies are conducted to produce an advanced ceramic coating, which reveals superior chemical and mechanical strength, on metal base structure used in chemical plant. This advanced coating on metallic frame can replace ceramic delivery pipe and reaction chamber used in chemical plant, which are operated in hi-temperature and corrosive/erosive environment. An dual spraying is adopted to reduce the residual stress in order to increase the coating thickness and the residual stress is estimated by in-situ manner. Then new methodology is tried to form special coating of yttrium aluminum garnet(YAG), which reveals hi-strength and low-creep rates at hi-temperature, superior anti-corrosion property, hi-stability against Alkali-Vapor corrosion, and so on, on iron base structure. To verify the formation of YAG during thermal spraying, XRD(X ray diffraction) technique was used.

Gain Tuning of a Fuzzy Logic Controller Superior to PD Controllers in Motor Position Control

  • Kim, Young-Real
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.14 no.3
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    • pp.188-199
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    • 2014
  • Although the fuzzy logic controller is superior to the proportional integral derivative (PID) controller in motor control, the gain tuning of the fuzzy logic controller is more complicated than that of the PID controller. Using mathematical analysis of the proportional derivative (PD) and fuzzy logic controller, this study proposed a design method of a fuzzy logic controller that has the same characteristics as the PD controller in the beginning. Then a design method of a fuzzy logic controller was proposed that has superior performance to the PD controller. This fuzzy logic controller was designed by changing the envelope of the input of the of the fuzzy logic controller to nonlinear, because the fuzzy logic controller has more degree of freedom to select the control gain than the PD controller. By designing the fuzzy logic controller using the proposed method, it simplified the design of fuzzy logic controller, and it simplified the comparison of these two controllers.

The Effect of Superior Leadership on Job Stress (상급자의 리더십이 직무스트레스에 미치는 효과: 공군 정비사를 대상으로)

  • Ahn, Kwan-Young;Son, Yong-Seung
    • Journal of the Korea Safety Management & Science
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    • v.13 no.1
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    • pp.75-80
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    • 2011
  • This paper reviewed the relationship between superior leadership and job stress responses, and the moderating effect of age in maintenance area of air force. Based on the responses from 450 air force maintenance persons, the results of multiple regression analysis showed that transactional leadership has negative relationship with physiological stress response, charisma has negative relationship with psychological stress, and individual consideration has negative relationship with behavioral stress. In moderating effects, age has negative effect on the relationship between transactional leadership and physiological stress response, and age has positive effect on the relationship between charisma and psychological stress response.

The Investigate Study of Textile Character in Kobong-cotton (고봉목화의 섬유특성 분석)

  • Lee, Kwang-Woo
    • Journal of the Korean Society of Fashion and Beauty
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    • v.3 no.2 s.2
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    • pp.47-54
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    • 2005
  • The purpose of this study was to investigate a specific character on products of American-cotton(Kobong) with cultivated in Sinbong-dong, Sangju City from 1997 to 2003 years. The results of this study were as follows: 1. The Kobong cotton of producted in Sangju city was superior in quality than Korean-cotton. 2. The cotton producted in 1998, 2002 and 2003 was inferior in quality than the anther producted cotton. The reasons was a heavy rain at 1998, Rusa typhoon at 2002 and Maemi typhoon at 2003 in sangju city. But Kobong-cotton was superior in quality than the Korean-cotton. Since it is so, Kobong(New improved variety of American-cotton) was superior in quality than the another kinds(Korean-cotton) from producted of cotton fibers

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Power Electronics Open-Source Educational Platform

  • Pozo-Ruz, Ana;Aguilera, F. David Trujillo;Moron, M. Jose;Rivas, Ernesto
    • Journal of Power Electronics
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    • v.12 no.5
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    • pp.842-850
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    • 2012
  • Learning Power Electronics is essential in both electrical and electronic engineering fields and the introductory courses are similar in many universities. Taking this premise into account, an educational computer-aided platform for power electronics will be presented in this paper. This educational platform includes an e-book, a set of power electronics animations, Java simulations, as well as several hands-on training sessions. The main advantages of this platform are twofold. First, all necessary teaching tools are combined on a single platform. And secondly, access to this platform is available free of charge and with no complicated registration requirements. In addition to traditional teaching techniques, the use of this platform has demonstrated an increase in student participation and has consistently improved their academic performance. Data consist of surveys, which guarantee both reliability and validity through psychometric techniques.

Effect of Residual Carbon on the Microstructure Evolution during the Sintering of M2 HSS Parts Shaping by Metal Injection Moulding Process

  • Herranz, G.;Levenfeld, B.;Varez, A.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.225-226
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    • 2006
  • In this present investigation, Metal Injection Moulding (MIM) of M2 High Speed Steel (HSS) parts using a wax-High Density Polyethylene (HDPE) binder is shown. The elimination of organic binder was carried out by thermal debinding under inert atmosphere. In order to keep carbon in the sample that could improve the sintering process, incomplete debinding was performed between 450 and $600^{\circ}C$. The specimens were sintered at temperatures between 1210 and $1280^{\circ}C$ in high vacuum atmosphere, obtaining the 98% of the theoretical density. In the samples with higher residual carbon content, the sintering window was extended up to 20 degrees and the optimum temperature was lower.

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A Study on the Wearing Effect and Wearing Comfort of Brassiere on the Market (시판 브래지어의 착용감 및 착용효과 분석)

  • 김정희;이경화
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.8
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    • pp.1432-1443
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    • 2001
  • The purpose of this study is to offer basic data to manufacture superior brassiere, by finding out wearing effect and wearing comfort after select high-functional brassiere and usual brassiere of brassiere on the market, and by analyzing the features of superior brassiere in wearing effect and comfort. The results of this research are as follows; 1) As a result of testing the wearing effect when wear a brassiere, the revision effect of high-functional brassiere was higher than that of usual one. But, from questions on general comfortable feeling. the wearing comfort of usual brassiere was higher in comparison with high-functional brassiere. In the questions for comparison and evaluation, the frequency of hard type-functional brassiere was highest. 2) As a result of examining the wearing effect and comfort of brassiere by each type, the wearing effect of high-functional brassiere was excellent. because of the difference in the size, construction, and material of brassiere, and the wearing comfort of hard type high-functional brassiere were superior relatively.

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A Study on The Assessment Method of Gait Analysis for Ankle Assembly Using Ground Reaction Force (지면반발력을 이용한 인공족관절의 보행평가 기법에 관한 연구)

  • Kim Sung Min;Kim Sung Jae;Bae Ha Suk;Choi Byoung Cheol
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.5 s.170
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    • pp.197-204
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    • 2005
  • In this study, ground reaction force(GRF), absolute symmetry index(ASI) and coefficient of variation(CV) of fixed, single-axis and multi-axis prosthetic ankle assemblies were investigated to show the biomechanical evaluation for above knee amputees. In the experiments, 37 normal male volunteers, two male and two female AK amputees were tested with fixed, single-axis and multi-axis prosthetic ankle assembly. A gait analysis was carried out to derive the ratio of GRF to weight as the percentage of total stance phase for ten points. The results showed that fixed-axis ankle was superior to the other two ankle assemblies for the characteristic of forwarding and breaking forces. Multi-axis ankle was relatively superior to the other two ankle assemblies for gait balancing and movement of the center for mass. single-axis ankle was relatively superior to the other two ankle assemblies for CV and ASI of GRF.

A time domain analysis of train induced vibrations

  • Romero, A.;Galvin, P.;Dominguez, J.
    • Earthquakes and Structures
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    • v.3 no.3_4
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    • pp.297-313
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    • 2012
  • This paper is intended to show the robustness and capabilities of a coupled boundary element-finite element technique for the analysis of vibrations generated by high-speed trains under different geometrical, mechanical and operation conditions. The approach has been developed by the authors and some results have already been presented. Nevertheless, a more comprehensive study is presented in this paper to show the relevance and robustness of the method which is able to predict vibrations due to train passage at the vehicle, the track, the free-field and any structure close to the track. Local soil discontinuities, underground constructions such as underpasses, and coupling with nearby structures that break the uniformity of the geometry along the track line can be represented by the model. Non-linear behaviour of the structures can be also considered. Results concerning the excitation mechanisms, track behaviour and sub-Rayleigh and super-Rayleigh train speed are summarized in this work.

An Analysis on the Instruction Effectiveness of Ability Grouping based on 'Setting' ('세팅(setting)'에 의한 능력별 집단편성 수업의 효과 분석)

  • Lee, Sang-Chul
    • Journal of Fisheries and Marine Sciences Education
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    • v.24 no.3
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    • pp.446-458
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    • 2012
  • This research aims to analyze on the instruction effectiveness of ability grouping based on 'setting' and the result is as following. Superior group had a positive effect from the aspect of self-conception, satisfaction on class, and learning attitude while average and inferior group had a negative effect from the aspect of self-conception, satisfaction on class, and learning attitude. Therefore, the point seems to be that ability-grouping class based on 'setting' only helps the students in the superior group. Therefore, it is necessary to reconsider the educational policy of variable curriculum classroom by achievement Level implemented by current ability-grouping. A method should be prepared to help all the students in superior, average, and inferior level.