• Title/Summary/Keyword: Intermediate Technology

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The 'Middle-Income Country Trap' and Technological Catch-up: The Case of the Machine Tools Industry in Korea (기계산업에서의 중진국 함정과 기술추격: 한국 기계산업의 사례)

  • Kim Yoon-Zi
    • Journal of Technology Innovation
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    • v.14 no.1
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    • pp.147-175
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    • 2006
  • One of the biggest problems of Korean economy is polarization of firms for export and domestic demand and that of conglomerates and SME's achievement. One of the culprits lies weakness of intermediate industry such as machine tool. Since intermediate industry is important path where export performance affects domestic demand and whose actor usually is SMEs with high spill over effect in labor market. Especially, intermediate industry Is vulnerable because of industrial policy biased In backward linkage effect. However if a country fails to develop intermediate industry above some critical point, that country would fall in low-tech equilibrium without growth. In case of benign circle where final goods industry growth leads growth of intermediate industry and again it leads that of final goods industry, it can reach high-tech equilibrium. By contrast, in opposite case where in industrialization latecomer fails to link industries likewise above some critical point that country would fall in low-tech equilibrium without growth. Moreover, for several reasons, machine tool firms of Korea have difficulty in catching up technology above critical point. Firstly. Conglomerate demander neglects their product. Secondly, even after success of development overcoming difficulties they fail to get market share for response of dumping of foreign competitors. And the last one is patent litigation of foreign competitors that incapacitate the technology development. For these, Korean machine tool firms fell in 'middle-income country trap' itself, since they stuck in some extent when they technologically catch up. Consequently, for latecomer country in machine tool industry to leapfrog meaningfully policy support is necessary, Weak intermediate industry does not Induce domestic firms and remained fragile. Therefore, localization, policy should reflect condition of technological catch up more than before, in order to be effective and fruitful. There should be turning point over relationship between conglomerates, major demander of machine tool and SME's, for only with active purchasing of conglomerate Korean machine industry can grow.

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Experimental study on propagation behavior of three-dimensional cracks influenced by intermediate principal stress

  • Sun, Xi Z.;Shen, B.;Zhang, Bao L.
    • Geomechanics and Engineering
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    • v.14 no.2
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    • pp.195-202
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    • 2018
  • Many laboratory experiments on crack propagation under uniaxial loading and biaxial loading have been conducted in the past using transparent materials such as resin, polymethyl methacrylate (PMMA), etc. However, propagation behaviors of three-dimensional (3D) cracks in rock or rock-like materials under tri-axial loading are often considerably different. In this study, a series of true tri-axial loading tests on the rock-like material with two semi-ellipse pre-existing cracks were performed in laboratory to investigate the acoustic emission (AE) characteristics and propagation characteristics of 3D crack groups influenced by intermediate principal stress. Compared with previous experiments under uniaxial loading and biaxial loading, the tests under true tri-axial loading showed that shear cracks, anti-wing cracks and secondary cracks were the main failure mechanisms, and the initiation and propagation of tensile cracks were limited. Shear cracks propagated in the direction parallel to pre-existing crack plane. With the increase of intermediate principal stress, the critical stress of crack initiation increased gradually, and secondary shear cracks may no longer coalesce in the rock bridge. Crack aperture decreased with the increase of intermediate principal stress, and the failure is dominated by shear fracturing. There are two stages of fracture development: stable propagation stage and unstable failure stage. The AE events occurred in a zone parallel to pre-existing crack plane, and the AE zone increased gradually with the increase of intermediate principal stress, eventually forming obvious shear rupture planes. This shows that shear cracks initiated and propagated in the pre-existing crack direction, forming a shear rupture plane inside the specimens. The paths of fracturing inside the specimens were observed using the Computerized Tomography (CT) scanning and reconstruction.

Design of Intermediate Die for Spline Drawing (스플라인형상 인발을 위한 중간패스 단면형상 설계)

  • Lee, T.K.;Lee, J.E.;Lee, S.K.;Kim, B.M.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.10a
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    • pp.337-340
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    • 2008
  • The cross section shape of intermediate die is one of important parameters to obtain dimensional accuracy of final product in shaped drawing process. Until now it has been designed by the experience or trial and error of the expert. In this study, the cross section shape of intermediate die fur spline shape is determined by the electronic field analysis, shape factor method. The result of the electronic field analysis, shape factor method has been compared with that of the present method. The effects of cross section shape on the dimensional accuracy were investigated by using FE analysis. And then the multi-stage shaped drawing experiments were performed to verify the results of FE analysis. As a result, the cross section shape from the electronic field analysis had the good dimensional accuracy. The electronic field analysis can be used for the method to obtain the cross section shape of intermediate die in shaped drawing process.

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Survey evaluation of thermal boundary condition in the inside and outside of double skin facade

  • Shin, Hyun-Cheol;Jang, Gun-Eik
    • KIEAE Journal
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    • v.15 no.4
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    • pp.29-35
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    • 2015
  • Purpose: Double skin facade is a representative advantageous passive technology of building skin in the aspect of energy saving and environment improvement, reduces heat loss with buffer space in winter season and enhances indoor air and comfort of residents by activating natural ventilation in mid-season. However, in summer season, temperature increase in the intermediate space due to solar energy from exterior transparent skin could be a potential problem; also, relatively weak buoyancy of air caused by low density difference between double-skin facade could increase cooling load as air of intermediate space in high temperature hangs. However, proof data is insufficient to objectify such phenomenon. Method: In this study, researchers surveyed air temperature of intermediate space and airflow and diagnosed its cause targeting on applied multistory facade in the building which gives thermal uncomfort to residents. Also, the researchers produced Solar-air heat transfer coefficient meter, measured thermal boundary condition of double-skin facade, and presented the result of measurement as an objectified verification material regarding overheating phenomenon in the intermediate space of double-skin facade in summer season. Result: Inefficient condition was verified that total heat increases and overheating due to insufficient natural ventilation in multistory facade. In addition, logic behind preceding research was objectified and verified regarding high temperature phenomenon in the intermediate space which could increase cooling load in summer season.

Assessing the Value of Research and Exploratory Development Stage of an R&D project under Duopoly and Oligopolistic Competition

  • 최돈호;김지수
    • Journal of Technology Innovation
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    • v.4 no.1
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    • pp.165-183
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    • 1996
  • In acquiring and transferring a superior knowledge assesing the intermediate result value of a competitive R&D project is very important for a firm engaging in R&D. Most existing literatures on R&D evaluation are concerned with project selection and resource allocation. In this paper the stage of an R&D project is classified into research, exploratory development, and development. And a model is suggested which evaluates the intermediate result value before completion of development stage under duopoly and oligopolistic competition. Assessed value of the intermediate result transferred to the next tier company can be used as a minimum acceptable price to the inventor when more advanced knowledge acquired through R&D is transferred to the next tier one. The model suggested is composed of structural variables including research cost, success rates, potential profits, discount rate degree of competition. By using exponential distribution for invertion process time in each stage, we derive a formula that can assess the value of the intermediate result, and we demonstrate how the model can be applied to a competitive R&D situation through an example.

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A 2-GHz 8-bit Successive Approximation Digital-to-Phase Converter (2 GHz 8 비트 축차 비교 디지털-위상 변환기)

  • Shim, Jae Hoon
    • Journal of Sensor Science and Technology
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    • v.28 no.4
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    • pp.240-245
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    • 2019
  • Phase interpolation is widely adopted in frequency synthesizers and clock-and-data recovery systems to produce an intermediate phase from two existing phases. The intermediate phase is typically generated by combining two input phases with different weights. Unfortunately, this results in non-uniform phase steps. Alternatively, the intermediate phase can be generated by successive approximation, where the interpolated phase at each approximation stage is obtained using the same weight for the two intermediate phases. As a proof of concept, this study presents a 2-GHz 8-bit successive approximation digital-to-phase converter that is designed using 65-nm CMOS technology. The converter receives an 8-phase clock signal as input, and the most significant bit (MSB) section selects four phases to create two sinusoidal waveforms using a harmonic rejection filter. The remaining least significant bit (LSB) section applies the successive approximation to generate the required intermediate phase. Monte-Carlo simulations show that the proposed converter exhibits 0.46-LSB integral nonlinearity and 0.31-LSB differential nonlinearity with a power consumption of 3.12 mW from a 1.2-V supply voltage.

An Experimental Phonetic Study of Prosodics Units in Real Utterances for Spoken French Teaching (프랑스 구어 교육을 위한 실제 발화 운율 단위의 실험 음성학적 고찰)

  • Lee Eun-Yung;Yuh Hea-Oak;Lee Kyung-Min
    • MALSORI
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    • no.47
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    • pp.15-29
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    • 2003
  • When intonation in French is analysed in terms of a multi-dimentional and hierarchical structure, each of the prosodic units such as accent phrases(having different combinations of the basic tonemes L and H), pre-sentencial and post-sentencial long pauses, intonation phrases(containing boundary intonation), as well as intermediate phrases can be considered being realized on a separate tier. Unlike on the tiers where accent phrases and intonation phrases occur, an intonation rhythm consisting of plateaus is realised on that of intermediate phrases. This intonation rhythm consisting of plateaus is one of the significant factors that lead a basic French metrical rhythm. This paper first shows the types of combinations of the basic tonemes L and H found in French accent phrases. Secondly, this paper examines the roles intermediate phrases and plateaus play in French. Finally, this paper argues that intermediate phrases are the metrical units actually adopted as real utterance units in French.

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A Study on Metal-Porcelain Fusing Layer in Porcelain Fused to High Gold Alloy (도재소부용 고금함유금합금의 연구 - 도재 결합층을 중심으로 -)

  • Lee, Kee-Dae;Kwak, Dong-Ju
    • Journal of Technologic Dentistry
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    • v.31 no.3
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    • pp.15-20
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    • 2009
  • The success of the porcelain fused to gold alloy restoration depends not only on the choice of materials but to a larger degree on the technical skills. The porcelain fused to metal(PFM) alloys containing gold are commonly use for dental purposes in dental laboratory. The gold-colored alloys contain primarily gold, platinum, palladium, and silver, with minimum amounts of such metals as tin, iridium, or titanium. The purpose of this study is on the metal-porcelain fusing layer in porcelain fused to high gold alloy Principal results are as follows. The hardness number(Hv) of PFG is respectively $140.2{\pm}12.6$ in as-casted, $164.3{\pm}14.3$ in heat-treated, $186.6{\pm}20.4$ in fired-treated. The formation of the fusing(intermediate) layer caused by components fusing the interface of porcelain and gold alloy. The main components of the fusing(intermediate) layer are Na, Al, Si, K, Zn, Zr and Ce. The intermediate layer formed by the 2nd firing is more larger than the intermediate layer formed by the 1st firing.

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Ultimate strength of stiffened plates with pitting corrosion

  • Rahbar-Ranji, Ahmad;Niamir, Nabi;Zarookian, Arvin
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.7 no.3
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    • pp.509-525
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    • 2015
  • Predicting residual strength of corroded plates is of crucial importance for service life estimation of aged structures. A series of nonlinear finite element method is employed for ultimate strength analysis of stiffened plates with pitting corrosion. Influential parameters, including plate thickness, type and size of stiffeners, pit depth and degree of pitting are varied and more than 208 finite element models are analyzed. It is found that ultimate strength is reduced by increasing pit depth to thickness ratio. Thin and intermediate plates have minimum and maximum reduction of ultimate strength with stronger stiffeners, respectively. In weak stiffener, reduction of ultimate strength in thin and intermediate plates depends on DOP. Reduction of ultimate strength in thick plates depends on thickness of plate and DOP. For intermediate plates, reduction for all stiffeners regardless of shape and size are the same.

SAFETY ASPECTS OF INTERMEDIATE HEAT TRANSPORT AND DECAY HEAT REMOVAL SYSTEMS OF SODIUM-COOLED FAST REACTORS

  • CHETAL, SUBHASH CHANDER
    • Nuclear Engineering and Technology
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    • v.47 no.3
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    • pp.260-266
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    • 2015
  • Twenty sodium-cooled fast reactors (SFRs) have provided valuable experience in design, licensing, and operation. This paper summarizes the important safety criteria and safety guidelines of intermediate sodium systems, steam generators, decay heat removal systems and associated construction materials and in-service inspection. The safety criteria and guidelines provide a sufficient framework for design and licensing, in particular by new entrants in SFRs.