• Title/Summary/Keyword: strength index

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STUDY ON EQUATORIAL, BUBBLES DETECTED BY SPS IMS ONBOARD THE KOMPSAT-I (KOMPSAT-1 SPS IMS에 관측된 적도 이온층 밀도 불균일 현상에 대한 연구)

  • 박재흥;이재진;이은상;민경욱
    • Journal of Astronomy and Space Sciences
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    • v.19 no.2
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    • pp.133-140
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    • 2002
  • Space Physics Sensor onboard the KOMPSAT-1, which was launched at 1999, had transmitted ionospheric data during the solar maximum from June 2000 to August 2001. When the KOMPSAT-1 has passed the equatorial region, equatorial bubbles, in which the electron density abruptly decreases, had frequently been detected. Statistical analysis of the data obtained during the entire operational period shows equatorial bubbles frequently occur across the Atlantic region where the geomagnetic field strength is weak. Also, equatorial bubbles occur more frequently for lower Kp index. The results are in good agreement with the previous observations by DMSP satellites and radio experiments at the Peruvian sector The correlation between electron density and the electron temperature shows various behaviors from event to event.

Study on the Influencing Factors of TFP of Low-carbon Tourism Distribution

  • Cheng, Xiaoyu;Jiang, Keshen
    • The Journal of Industrial Distribution & Business
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    • v.8 no.7
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    • pp.13-20
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    • 2017
  • Purpose - Performance appraisal has a significant influence on the development of low-carbon tourism distribution. Research design, data, and methodology - Data of this study are collected from 27 provinces (cities) of China. SBM-Malmquist model is used to measure the TFP and its dynamic changes of low-carbon tourism distribution; TOBIT model is used to discuss the factors of TFP of low-carbon tourism distribution. Results - The results show that, there are obvious differences among regional TFP of low-carbon tourism distribution, the average change tends to grow positively in general, and the western region grows fastest on average due to the improvement of technical efficiency and technical progress, while there are technical efficiency improvement but technical regresses in eastern and central regions. The economic scale, economic strength, structure of energy consumption, location quotient and government regulation have a significant positive effect on the TFP of low-carbon tourism; energy intensity, industrial structure and opening degree have a negative effect; investments in fixed assets, intensity of R&D fund and urbanization rate have no significant influence on the TFP of low-carbon tourism. Conclusions - Improving the productivity of low-carbon tourism and reducing regional differences are effective ways to develop low-carbon tourism and enhance tourism competitiveness.

Computer-Aided Alloy Design of Insert Metal for Transient Liquid Phase Bonding of High Aluminum Ni-base Superalloys

  • Nishimotd, Kazutoshi;Saida, Kazuyoshi
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.803-808
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    • 2002
  • A computer-aided alloy-designing technique to develop the insert metal for transient liquid phase (TLP) bonding was applied to high aluminum Ni-base superalloys. The main procedure of a mathematical programming method was to obtain the optimal chemical composition through rationally compromising the plural objective performances of insert metal by a grid-search which involved data estimation from the limited experimental data using interpolation method. The objective function Z which was introduced as an index of bonding performance of insert metal involved the melting point, hardness (strength), formability of brittle phases and void ratio (bonding defects) in bond layer as the evaluating factors. The contour maps of objective function Z were also obtained applying the interpolation method. The compositions of Ni-3.0%Cr-4.0%B-0.5%Ce (for ${\gamma}$/${\gamma}$/${\beta}$ type alloy) and Ni3.5%Cr-3.5%B-3%Ti (for ${\gamma}$/${\gamma}$ type alloy) which optimized the objective function were determined as insert metal. SEM observations revealed that the microstructure in bond layers using the newly developed insert metals indicated quite sound morphologies without forming microconstituents and voids. The creep rupture properties of both joints were much improved compared to a commercial insert metal of MBF-80 (Ni-15.5%Cr-3.7%B), and were fairly comparable to those of base metals.

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Ageing behavior of Hanji sheet by mucilage (점액질에 따른 한지 sheet의 열화 거동)

  • Lee, Min-Hyung;Kim, Kang-Jae;Eom, Tae-Jin
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2011.04a
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    • pp.271-277
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    • 2011
  • Hanji(Korean traditional paper) is made from bark of paper mulberry(Broussonetia kazinoki). For a long time, Hanji has been used in various fields, such as paintings, printing paper, as specialty paper. The utilization of Hanji will become more and more diverse. One of the characteristic properties of Hanji is a long life time comparing to western paper. The mucilage which must be used in Hanji manufacturing should effect the conservation properties of Hanji. The effectiveness of the mucilage in aging of Hanji was evaluated in this paper. Strength properties of thermal aged Hanji made with synthetic mucilage decreased more slowly than those of Hanji made with natural mucilage. As prolonged aging time, all Hanji made mucilage increased oxidation index. But, Hanji made with PAM was most stable in oxidation of cellulose.

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Adaptation of Evidence-based Surgical Wound Care Algorithm

  • Han, Jung-Yeon;ChoiKwon, Smi
    • Journal of Korean Academy of Nursing
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    • v.41 no.6
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    • pp.768-779
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    • 2011
  • Purpose: This study was designed to adapt a surgical wound care algorithm that is used to provide evidence-based surgical wound care in a critical care unit. Methods: This study used, the 'ADAPTE process', an international clinical practice guideline development method. The -'Bonnie Sue wound care algorithm' - was used as a draft for the new algorithm. A content validity index (CVI) targeting 135 critical care nurses was conducted. A 5-point Likert scale was applied to the CVI test using a statistical criterion of .75. Results: A surgical wound care algorithm comprised 9 components: wound assessment, infection control, necrotic tissue management, wound classification by exudates and depths, dressing selection, consideration of systemic factors, wound expected outcome, reevaluate non-healing wounds, and special treatment for non-healing wounds. All of the CVI tests were ${\leq}$.75. Compared to existing wound care guidelines, the new wound care algorithm provides precise wound assessment, reliabilities of wound care, expands applicability of wound care to critically ill patients, and provides evidence and strength of recommendations. Conclusion: The new surgical wound care algorithm will contribute to the advancement of evidence-based nursing care, and its use is expected as a nursing intervention in critical care.

A Study on Factors Influencing to Coefficient of Consolidation in Horizontal Direction (수평압밀계수의 영향인자에 관한 연구)

  • Kim, Chang-Seop;Park, Byung-Soo;Yoo, Nam-Jae
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.81-89
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    • 2008
  • This paper is results of investigating the dominant factors influencing to coefficient of consolidation in horizontal direction of Korean marine clays and their correlations through literature review. From the results of analyzing data obtained from field tests such as piezocone penetration and dilatometer tests as well as laboratory tests, coefficient of consolidation in the horizontal direction was found to increase with increase of stiffness index of soil while it decreases with the increase of dissipation time of pore pressure developed during field tests. In general, the coefficient of consolidation in the horizontal direction tends to increase with increase of undrained shear strength and preconsolidation pressure although correlation between them are relatively low. Friction ratio has a high correlation with coefficient of consolidation in the horizontal direction in case of friction ratio being greater than 1.0. For methods of estimating coefficient of consolidation in the horizontal direction with different testing device, values obtained from methods of P2-logt and DMT-A with dilatometer were quite similar to values from piezocone penetration test. Consistency of soil is quite proportional to coefficient of consolidation in the horizontal direction. Clear correlation between coefficients of consolidation in the horizontal and the vertical directions could not be found. coefficient of consolidation in the horizontal direction estimated from the results of field test tends to be 1.13~3.11 times greater than that obtained from laboratory tests.

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Physical Properties of Extruded Snack Made of Dried Onion and Onion Pomace (건조양파착즙박과 건조양파를 이용한 압출스낵의 물리적 특성)

  • 기해진;류기형;박양균
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.1
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    • pp.64-69
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    • 2001
  • In order to use onion pomace produced from concentration processing of onion juice, dried onion pamace and dried onion were mixed with corn grits at levels of 10, 20, and 30% and extruded in a twin-screw extruder. The physical properties of the extruded onion snack were investigated. The expansion ratio of the extruded onion pomace snack and onion snack and onion snack decreased with onion content. The water absorption index decreased with the onion content. The lightness and the redness of the onion snack decreased and increased as the incorporation level of onion increased, respectively. Native corn grits showed crystalline peaks at 15.2$^{\circ}$, 17.3$^{\circ}$, 17.9$^{\circ}$ and 23.3$^{\circ}$. However, the onion snack did not show the crystalline peaks as native corn grits and showed small peaks at 12.9$^{\circ}$ and 19.8$^{\circ}$. The onion snack showed lower gelatinization temperature and enthalpy than raw corn grits regardless of the onion contents. The rupture strength of the onion pomace snack and onion snack increased with the onion concentration.

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Debonding forces of three different customized bases of a lingual bracket system

  • Sung, Jang-Won;Kwon, Tae-Yub;Kyung, Hee-Moon
    • The korean journal of orthodontics
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    • v.43 no.5
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    • pp.235-241
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    • 2013
  • Objective: The purpose of this study was to investigate whether extension of the custom base is necessary for enhancement of bond strength, by comparing the debonding forces and residual adhesives of 3 different lingual bracket systems. Methods: A total of 42 extracted upper premolars were randomly divided into 3 groups of 14 each for bonding with brackets having (1) a conventional limited resin custom base; (2) an extended gold alloy custom base: Incognito${TM}$; and (3) an extended resin custom base: KommonBase${TM}$. The bonding area was measured by scanning the bracket bases with a 3-dimensional digital scanner. The debonding force was measured with an Instron universal testing machine, which applied an occlusogingival shear force. Results: The mean debonding forces were 60.83 N (standard deviation [SD] 10.12), 69.29 N (SD 9.59), and 104.35 N (SD17.84) for the limited resin custom base, extended gold alloy custom base, and extended resin custom base, respectively. The debonding force observed with the extended resin custom base was significantly different from that observed with the other bases. In addition, the adhesive remnant index was significantly higher with the extended gold alloy custom base. Conclusions: All 3 custom-base lingual brackets can withstand occlusal and orthodontic forces. We conclude that effective bonding of lingual brackets can be obtained without extension of the custom base.

Optical and Mechanical Properties of Commercial Dental Enamel Porcelain (상용 치과 법랑질 도재의 광학적 및 기계적 특성)

  • Park, Hyung-Rang
    • Journal of Technologic Dentistry
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    • v.26 no.1
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    • pp.115-128
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    • 2004
  • In this study, optical and mechanical properties were investigated with 4 kinds of commercial dental enamels. As a result of EDS analysis $SiO_2,\;Na_{2}O,\;Al_{2}O_3\;and\;K_{2}O$ were the main components of commercial dental enamels. In case of H specimen, content of $SiO_2\;and\;K_2O$ were more than that of another specimens. Starting powder and fired specimens were glass ceramics which were consist of amorphous phase and leucite (crystalline) phase. Crystallization did not occurred during firing process, since the XRD peak intensity was similar between starting powder and fired specimens. As a result of differential thermal analysis, $T_g$ and crystalline temperature was varied with composition in the range of $548\sim576^{\circ}C$ and $735\sim780^{\circ}C$ respectively. 0.5mm thickness dental enamel specimens showed sufficient translucent properties. However, transmittance and reflectance were lower than 5% result from scattering due to the refractive index difference between glass and crystalline phase. 3 point bending strength was in the range of 73.9$\sim$101.8MPa which was similar or slightly higher than enamel of natural teeth and Vickers hardness was higher than enamel of natural teeth more than 100.

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Spherical Indentation Testing to Evaluate Mechanical Properties In 1Cr-1Mo-0.25V Steel (Spherical Indentation Testing에 의한 1Cr-1Mo-0.25V 강의 기계적 물성 평가)

  • Lee, J.M.;Nam, Y.H.;Nham, S.H.;Lee, S.S.;Lee, O.S.
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.266-271
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    • 2001
  • Spherical indentation technique was developed to evaluate the flow properties of metallic materials in carbon steel, stainless steel and alloys, etc. Through the spherical indentation test, differently degraded 1Cr-1Mo-0.25V steel's mechanical properties were observed and compared with conventional standard test data. The flow properties of 1Cr-1Mo-0.25V steels were estimated by analyzing the indentation load-depth curve. To characterize the flow property, we used material yield slope and constraint factor index rather than strain-hardening exponent because the variation of strain-hardening exponent was very little and the data showed irregularly. And the constraint factor's effect was small when the material yield slope was taken into account.

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