• Title/Summary/Keyword: regularities

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New possibilities of SHS for producing high-temperature materials

  • Natalya, Korobova;Soh, Dea-Wha
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.399-400
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    • 2005
  • Self-propagating High-temperature Synthesised (SHS) ceramics have been widely used for various electronic applications. The investigation on SHS materials has been reported. The purposes of this study were as follows: fabricating the high-temperature functional materials, and evaluating crystal structure and electrical properties. The regularities and peculiarities in SHS structures of high-temperature materials as a result of the molecular interactions during burning process are considered.

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A Multivariate Analytical Study on the Water of Han-River and the Streams flowing into Han-River Basin

  • Lee Chul;Kim Seungwon;Kim Min-Young
    • Bulletin of the Korean Chemical Society
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    • v.9 no.1
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    • pp.5-9
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    • 1988
  • Pattern recognition techniques have been applied for the extraction of some regularities of water samples under a wide variety of locations related to Han-River. For that purpose, an eigenvector analysis has been applied for defining each class so as to use the class as a training set for class analogy model of SIMCA. The models thus obtained have been used for the allocation of test samples between groups.

Servitization and Manufacturing Firms' Performance: Korean Firm-Level Data Evidence

  • Jae Wook Jung;Hyunsoo Kim
    • East Asian Economic Review
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    • v.26 no.4
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    • pp.257-277
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    • 2022
  • Does servitization improve manufacturing firms' performance, and in what condition? Following the seminal work of Crozet and Milet (2017), this study analyzes disaggregated firm-level data that covers 40,000 South Korean manufacturing firms surveyed by the Survey of Business Activities of Korea. We compute firm-level servitization intensity with available sales data of each firm by two-digit SIC sub-sectors. We find two novel empirical regularities: Korean servitization intensity distribution shows a very different shape from the French benchmark; Servitized firms tend to perform higher profitability and higher productivity than non-servitized firms.

A NOTE ON SOBOLEV TYPE TRACE INEQUALITIES FOR s-HARMONIC EXTENSIONS

  • Yongrui Tang;Shujuan Zhou
    • Journal of the Korean Mathematical Society
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    • v.61 no.2
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    • pp.341-356
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    • 2024
  • In this paper, apply the regularities of the fractional Poisson kernels, we establish the Sobolev type trace inequalities of homogeneous Besov spaces, which are invariant under the conformal transforms. Also, by the aid of the Carleson measure characterizations of Q type spaces, the local version of Sobolev trace inequalities are obtained.

Carbon Containing Compositions

  • Mansurova, R.M.;Mansurov, Z.A.;Soh, Deawha
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.335-338
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    • 2001
  • With the use of the electron microscopy and X-ray phase analysis the regularities of carbon deposit formation in process of methane and propane pyrolysis on the zeolites, Kazakhstan natural clays, chrome and bauxite sludge containing metal oxides of iron subgroup, have been studied. In process of over-carbonization the trivalent iron was reduced to metal form. In addition, the carbon tubes of divers morphology had been impregnated with ultra-dispersed metal particles. The kinetic parameters of carbon formation in process of methane decomposition on the zeolite CoO mixture surface were investigated by method of thermo-gravimetric analysis. The morphology and structure of formed carbon fibrils, with the metal particles fixed at their ends, have been investigated, the formation of branched carbon fibrils pattern, so called octopus, being found.

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SIMULATION OF RETURNABLE TRANSPORT ITEM SYSTEMS

  • Krabs, Andreas;Reinholz, Andreas
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.10a
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    • pp.83-89
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    • 2001
  • This paper provides a short description of the COMPASS-model which is a concept for the simulation of multiway systems. The focus of the COMPASS-model is to offer an opportunity to investigate the effects of redistribution strategies on logistic and monetary values in a system of returnable transport items (RTI). The modeling concept consists of five modules: topology, system load, distribution, redistribution, cost. It includes the integration of highly sophisticated evolutionary algorithms for the optimal solving of complex capacitated vehicle routing problems (CVRP) which are typical for RTI-systems. The results of first experiments with a COMPASS-based prototype are repeated. They reveal some basic regularities in RTI-systems.

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Ultra Precision Machining the Characteristics of IR Detection device HgCdTe (초정밀 가공기를 이용한 적외선 감지소자 HgCdTe의 절삭특성에 관한 연구)

  • Kim, Hyo-Sik;Yang, Sun-Choel;Kim, Myung-Sang;Kim, Geon-Hee;Lee, In-Je;Won, Jong-Ho;Cho, Byoung-Moo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.6 no.4
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    • pp.50-56
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    • 2007
  • This study aims to find the optimal cutting conditions, when are IR Detection device HgCdTe is machined with diamond tool of diamond turning machine. Machining technique for HgCdTe with single point diamond turning tool is reported in this paper. The main factors influencing the machined surface quality are discovered and regularities of machining process are drawn. It has been found HgCdTe has more and more important applications in the field of modern optics. The purpose of our research is to find the optimum machining conditions for ductile cutting of HgCdTe and apply the SPDT technique to the manufacturing of ultra precision optical components of brittle materials.

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Nano-turning of single crystal silicon (단결정 실리콘의 초정밀가공)

  • 김건희;도철진;홍권희;유병주;원종호;박상진;안병민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.11a
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    • pp.939-942
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    • 2000
  • Single point diamond turning technique for optical crystals is reported in this paper. The main factors influencing the machined surface quality are discovered and regularities of machining process are drawn. Optical crystals have found more and more important applications in the field of modern optics. Optical crystals are mostly brittle materials of poor machinability. The traditional machining method is polishing which has many shortcomings such as low production efficiency, poor ability to be automatically controlled and edge effect of the workpiece. The purpose of our research is to find the optimum machining conditions for ductile cutting of optical crystals and apply the SPDT technique to the manufacturing of ultra precision optical components of brittle material.

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The Characteristics of Ultra Precision Machining of Optical Crystal (광학소자의 초정밀절삭 특성에 관한 연구)

  • 김주환;박원규;김건희;원종호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.529-532
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    • 2003
  • Machining technique for optical crystals with single point diamond turning tool is reported in this paper. The main factors influencing the machined surface quality are discovered and regularities of machining process are drawn. Optical crystals have found more and more important applications in the field of modern optics. Optical crystals are mostly brittle materials of poor machinability. The traditional machining method is polishing which has many shortcomings such as low production efficiency. poor ability to be automatically controlled and edge effect of the workpiece. The purpose of our research is to find the optimum machining conditions for ductile cutting of optical crystals and apply the SPDT technique to the manufacturing of ultra precision optical components of brittle materials. As a result. the surface roughness is good when spindle speed is 200m/min. and teed rate is small. The influence of depth of cut is very small.

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A Study on Attitude Change in School Health Education (학교보건교육(學校保健敎育)에 있어서의 태도변화(態度變化)에 관(關)한 연구(硏究))

  • Moon, Jae Woo
    • Journal of the Korean Society of School Health
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    • v.4 no.2
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    • pp.146-158
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    • 1991
  • There is no doubt that the school health education in school health services is the most important component. But the concept and scope of the school health education is still not recognized and accepted satisfactorily in Korea. It is generally accepted that health education is a process of changing of attitude and behavior forward health practice. The term attitude refers to certain regularities on the part of an individual in feelings, thoughts, and predispositions to act toward some aspect of his environment. Attitudes have three components: affective, cognitive, and behavioral. The strategies of attitude change in school health education consist of incentive, justification, and coersion. In this study I explained reinforcement and motivation as the strategies of attitude change. The attitude change is not built in a day. When the teachers give the pupils knowledge, comprehension, or skill through school health education proper to each stage, then the attitude change will be realized.

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