• Title/Summary/Keyword: Path dependence

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Regional Innovation Effects of Technopoles of the World: the Case of Sophia Antipolis in France (세계적 테크노폴: 프랑스 소피아 앙티폴리스의 지역혁신 성과)

  • Shin, Dong-Ho
    • Journal of the Economic Geographical Society of Korea
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    • v.23 no.1
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    • pp.110-123
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    • 2020
  • The advanced industrial economies have been suffering from rapid de-industrialization since the 1970s. In order to overcome such crisis, many countries have attempted to establish science parks and technopoles. Sophia Antipolis in France is one of the best examples of the worldly known technopoles, which was launched in the late 1960s. However, earlier evaluations on the technopole were not positive, while there were no dynamic innovative activities among institutions and firms of the technopole at least up to the early 1990s. While some changes in such circumstance have been observed since then, this paper attempts to investigate the changes and transformations occurring from the technopole since the late 1990s. Based on the review of the recent publications, statistics and expert interviews, the current paper concludes that Sophia Antipolis has been transformed into a dynamic and innovative technopole.

Characteristics of Industrial Growth in the Peripheral Areas Based on Low-density Economics (저밀도 경제 논의와 주변부 지역 산업 성장의 특성)

  • Dochai Chung
    • Journal of the Economic Geographical Society of Korea
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    • v.25 no.4
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    • pp.583-599
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    • 2022
  • According to the discussion on the low-density economy in OECD industrial growth in remote area has played a central role in the members'economic recovery from the financial crisis in the mid-2000s. Based on the OECD's low-density economy this study examines the phenomena and spatial characteristics of industrial growth in peripheral areas of Korea. The growth of industries in the peripheral areas shows a similar growth characteristics as cases in the OECD members. Various manufacturing and service sectors as well as traditional sectors such as agriculture, forestry and fishing have grown in the peripheral areas since the mid-2000s. Firms in the peripheral areas form various cooperative networks to overcome the unfavorable regional conditions. The growth of new industries shows the possibility of path-dependent development in the periphery. Based on the results, implications on the policies for supporting the diversification of regional industries, setting flexible regional boundaries for policies, and linking policy sectors are derived.

Prestressed concrete bridges with corrugated steel webs: Nonlinear analysis and experimental investigation

  • Chen, Xia-chun;Bai, Zhi-zhou;Zeng, Yu;Jiang, Rui-juan;Au, Francis T.K.
    • Steel and Composite Structures
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    • v.21 no.5
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    • pp.1045-1067
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    • 2016
  • Concrete bridges with corrugated steel webs and prestressed by both internal and external tendons have emerged as one of the promising bridge forms. In view of the different behaviour of components and the large shear deformation of webs with negligible flexural stiffness, the assumption that plane sections remain plane may no longer be valid, and therefore the classical Euler-Bernoulli and Timoshenko beam models may not be applicable. In the design of this type of bridges, both the ultimate load and ductility should be examined, which requires the estimation of full-range behaviour. An analytical sandwich beam model and its corresponding beam finite element model for geometric and material nonlinear analysis are developed for this type of bridges considering the diaphragm effects. Different rotations are assigned to the flanges and corrugated steel webs to describe the displacements. The model accounts for the interaction between the axial and flexural deformations of the beam, and uses the actual stress-strain curves of materials considering their stress path-dependence. With a nonlinear kinematical theory, complete description of the nonlinear interaction between the external tendons and the beam is obtained. The numerical model proposed is verified by experiments.

The Electrical Resistivity of a SiCw/Al Alloy Composite with Temperature

  • Kim Byung-Geol;Dong Shang-Li;Park Su-Dong;Lee Hee-Woong
    • Korean Journal of Materials Research
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    • v.14 no.7
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    • pp.489-493
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    • 2004
  • The electrical property of MMC is essentially important to some applications such as power transmission lines and cables, electronic and electrical components as well as electromagnetic shielding equipments. The behavior of electrical resistivity of $SiC_{w}/Al$ alloy composites under as-extruded and annealed conditions has been investigated within the temperature range from room temperature to $450^{\circ}C$. It can be seen that within entire temperature range, the electrical resistivity of composites was higher than that of an unreinforced matrix alloy under the same condition of either as-extrusion or annealing. The temperature dependence of both exhibited positive incline like a typical metal. The variation of electrical resistivity of an unreinforced matrix alloy with temperature from ambient temperature to $450^{\circ}C$ was nearly monotonous, while those of composites increased monotonously at low temperature and rose to a high level after about $250^{\circ}C or 275^{\circ}C$. The difference of these temperature dependences on electrical resistivity can be interpreted as qualitatively the interfaces of $SiC_{w}$ fibers and matrix, where act as nucleation sites.

Effect of Joule Heating Variation on Phonon Heat Flow in Thin Film Transistor (줄 가열 변화에 따른 박막 트랜지스터 내 포논 열 흐름에 대한 수치적 연구)

  • Jin, Jae-Sik;Lee, Joon-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.10
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    • pp.820-826
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    • 2009
  • The anisotropic phonon conductions with varying Joule heating rate of the silicon film in Silicon-on-Insulator devices are examined using the electron-phonon interaction model. It is found that the phonon heat transfer rate at each boundary of Si-layer has a strong dependence on the heating power rate. And the phonon flow decreases when the temperature gradient has a sharp change within extremely short length scales such as phonon mean free path. Thus the heat generated in the hot spot region is removed primarily by heat conduction through Si-layer at the higher Joule heating level and the phonon nonlocality is mainly attributed to lower group velocity phonons as remarkably dissimilar to the case of electrons in laser heated plasmas. To validate these observations the modified phonon nonlocal model considering complete phonon dispersion relations is introduced as a correct form of the conventional theory. We also reveal that the relation between the phonon heat deposition time from the hot spot region and the relaxation time in Si-layer can be used to estimate the intrinsic thermal resistance in the parallel heat flow direction as Joule heating level varies.

From Specialisation to Diversification in Science and Technology Parks

  • Hassink, Robert;Hu, Xiaohui
    • World Technopolis Review
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    • v.1 no.1
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    • pp.6-15
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    • 2012
  • Science and technology parks have been popular among policy-makers at several spatial levels to promote innovation and economic growth of certain localities. However, this mainly property-led policy tool has been criticised for two reasons. First, it often failed to successfully support regional networking and technology transfer to regional firms. Only unplanned science and technology parks, such as Silicon Valley, seem to have been successfully fostering regional networking and technology transfer which has led, in turn, to the development of competitive innovative clusters. Secondly, it has too often bet on the same horses and become too specialised in the same fields, such as in micro-electronics or in biotechnology. This specialisation has been theoretically supported by the cluster concept. It has led to both a zero sum game of competition between locations as well as potentially negative path dependence and lock-ins. This paper suggests increasingly supporting diversification in science and technology parks by bringing together hitherto unconnected technologies. Several recently discussed concepts could be used to support diversification, such as related variety (Frenken et al. 2007), regional branching (Boschma and Frenken 2011), regional innovation platforms (Harmaakorpi et al. 2011) and transversality (Cooke 2011).

Measurement of soot concentration in flames using laser-induced incandescence method (레이저 가열 측정법을 이용한 화염 내 매연 농도 측정)

  • Jurng, Jong-Soo
    • Journal of the Korean Society of Combustion
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    • v.1 no.1
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    • pp.75-82
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    • 1996
  • Laser induced incandescence, LII, recently developed technique for measuring soot concentration in flames, can overcome most of limitations of conventional laser extinction measurement. In this study, experiments were performed to investigate the effect of laser intensity, detection wavelength, and also laser beam quality on both LII signal at a particular position and peak-to-centerline LII signal ratio. The results of LII signal with increasing laser intensity shows its near-independence of laser intensity once threshold level of laser intensity has been reached. However, this near-independence depends on laser beam quality and the incident optical setup. The peak-to-centerline LII signal ratio slowly but continuously increases with laser power. This fact is due to the dependence of LII signal on particle mean diameter. LII signal is attenuated during it passes through the flame containing soot particles. The attenuation rate is inversely proportional to detection wavelength. In this study, LII signal at 680 nm band is 10% greater than the signal at 400 nm band.

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A Study on the Pseudo-exhaustive Test using a Netlist of Multi-level Combinational Logic Circuits (다층 레벨 조합논리 회로의 Net list를 이용한 Pseudo-exhaustive Test에 관한 연구)

  • 이강현;김진문;김용덕
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.5
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    • pp.82-89
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    • 1993
  • In this paper, we proposed the autonomous algorithm of pseudo-exhaustive testing for the multi-level combinational logic circuits. For the processing of shared-circuit that existed in each cone-circuit when it backtracked the path from PO to PI of CUT at the conventional verification testing, the dependent relation of PI-P0 is presented by a dependence matrix so it easily partitioned the sub-circuits for the pseudo-exhaustive testing. The test pattern of sub-circuit's C-inputs is generated using a binary counter and the test pattern of I-inputs is synthesized using a singular cover and consistency operation. Thus, according to the test patterns presented with the recipe cube, the number of test pattrens are reduced and it is possible to test concurrently each other subcircuits. The proposed algorithm treated CUT's net-list to the source file and was batch processed from the sub-circuit partitioning to the test pattern generation. It is shown that the range of reduced ration of generated pseudo-exhaustive test pattern exhibits from 85.4% to 95.8% when the average PI-dependency of ISACS bench mark circuits is 69.4%.

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Non-specific in vivo inhibition of CK1 by the pyridinyl imidazole p38 inhibitors SB 203580 and SB 202190

  • Shanware, Naval P.;Williams, Leah M.;Bowler, Michael J.;Tibbetts, Randal S.
    • BMB Reports
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    • v.42 no.3
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    • pp.142-147
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    • 2009
  • Small-molecule inhibitors of protein kinases have contributed immensely to our understanding of biological signaling path-ways and have been exploited therapeutically for the treatment of cancers and other disease states. The pyridinyl imidazole compounds SB 203580 and SB 202190 were identified as ATP competitive antagonists of the p38 stress-activated protein kinases and have been widely used to elucidate p38-dependent cellular processes. Here, we identify SB 203580 and SB 202190 as potent inhibitors of stress-induced CREB phosphorylation on Serine 111 (Ser-111) in intact cells. Unexpectedly, we found that the inhibitory activity of SB 203580 and SB 202190 on CREB phosphorylation was independent of p38, but instead correlated with inhibition of casein kinase 1 (CK1) in vitro. The inhibition of CK1-mediated CREB phosphorylation by concentrations of pyridinyl imidazoles commonly employed to suppress p38, suggests that in some cases conclusions of p38-dependence derived solely from the use of these inhibitors may be invalid.

A minimum ductility design method for non-rectangular high-strength concrete beams

  • Au, F.T.K.;Kwan, A.K.H.
    • Computers and Concrete
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    • v.1 no.2
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    • pp.115-130
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    • 2004
  • The flexural ductility of solid rectangular reinforced concrete beams has been studied quite extensively. However, many reinforced concrete beams are neither solid nor rectangular; examples include T-, ${\Gamma}$-, ${\Pi}$- and box-shaped beams. There have been few studies on the flexural ductility of non-rectangular reinforced concrete beams and as a result little is known about the possible effect of sectional shape on flexural ductility. Herein, the effect of sectional shape on the post-peak flexural behaviour of reinforced normal and high-strength concrete beams has been studied using a newly developed analysis method that employs the actual stress-strain curves of the constitutive materials and takes into account the stress-path dependence of the stress-strain curve of the steel reinforcement. It was revealed that the sectional shape could have significant effect on the flexural ductility of a concrete beam and that the flexural ductility of a T-, ${\Gamma}$-, ${\Pi}$- or box-shaped beam is generally lower than that of a solid rectangular beam with the same overall dimensions and the same amount of reinforcement provided. Based on the numerical results obtained, a simple method of ensuring the provision of a certain minimum level of flexural ductility to non-rectangular concrete beams has been developed.