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61.
Allan Afuah 《Research Policy》2004,33(8):1231-1246
In this paper, I explore the role that the impact of a technological change on a firm's co-opetitors plays in the firm's technology entry timing. I hypothesize that where a co-opetitor dominates in the co-opetitor-firm relationship, a firm's technology entry timing does not depend on the impact of the technology on the firm's capabilities as predicted by previous research. Rather, it depends on the impact of the change on the dominant co-opetitor. If the change is incremental to a dominant customer, for example, the focal incumbent firm will start development of the new technology before new entrants, irrespective of whether it is radical or incremental to focal firms. If the change is radical to the dominant co-opetitor, new entrant focal firms will start development of the new technology before incumbent focal firms. I explore these hypotheses using the case of three major technological changes in supercomputers: vector processors, minisupercomputers, and massively parallel processors.  相似文献   
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Honours study is viewed as a transition from undergraduate to postgraduate study and/or to enhanced career prospects. In Australia, Honours is usually an adjunct to the standard undergraduate degree. This paper provides an ethnographic study of 10 Australian Honours students. Seeing their experience through their reflections, in their own voices, reveals that Honours may be more than transitional – these students were transformed personally. Such emotionally charged transformations require academics to reflect on the best forms of support for Honours students.  相似文献   
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Mixture Rasch models have been used to study a number of psychometric issues such as goodness of fit, response strategy differences, strategy shifts, and multidimensionality. Although these models offer the potential for improving understanding of the latent variables being measured, under some conditions overextraction of latent classes may occur, potentially leading to misinterpretation of results. In this study, a mixture Rasch model was applied to data from a statewide test that was initially calibrated to conform to a 3‐parameter logistic (3PL) model. Results suggested how latent classes could be explained and also suggested that these latent classes might be due to applying a mixture Rasch model to 3PL data. To support this latter conjecture, a simulation study was presented to demonstrate how data generated to fit a one‐class 2‐parameter logistic (2PL) model required more than one class when fit with a mixture Rasch model.  相似文献   
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Herein is described the fabrication and use of a plastic multilayer 3-channel microfluidic fixture. Multilayer devices were produced by laser machining of plastic polymethylmethacrylate and polyethyleneterapthalate laminates by ablation. The fixture consisted of an array of nine individually addressable gold or gold/ITO working electrodes, and a resistive platinum heating element. Laser machining of both the fluidic pathways in the plastic laminates, and the stencil masks used for thermal evaporation to form electrode regions on the plastic laminates, enabled rapid and inexpensive implementation of design changes. Electrochemiluminescence reactions in the fixture were achieved and monitored through ITO electrodes. Electroaddressable aryl diazonium chemistry was employed to selectively pattern gold electrodes for electrochemical multianalyte DNA detection from double stranded DNA (dsDNA) samples. Electrochemical detection of dsDNA was achieved by melting of dsDNA molecules in solution with the integrated heater, allowing detection of DNA sequences specific to breast and colorectal cancers with a non-specific binding control. Following detection, the array surface could be renewed via high temperature (95 °C) stripping using the integrated heating element. This versatile and simple method for prototyping devices shows potential for further development of highly integrated, multi-functional bioanalytical devices.  相似文献   
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In this study, carbon fiber electrodes were incorporated within a hollow microneedle array, which was fabricated using a digital micromirror device-based stereolithography instrument. Cell proliferation on the acrylate-based polymer used in microneedle fabrication was examined with human dermal fibroblasts and neonatal human epidermal keratinocytes. Studies involving full-thickness cadaveric porcine skin and trypan blue dye demonstrated that the hollow microneedles remained intact after puncturing the outermost layer of cadaveric porcine skin. The carbon fibers underwent chemical modification in order to enable detection of hydrogen peroxide and ascorbic acid; electrochemical measurements were demonstrated using integrated electrode-hollow microneedle devices.  相似文献   
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While there is growing scholarly interest in returned and cyclical migration, and on young adult cultural or adventure seeking migration, there is still a lack of systematic empirical insights into how the experiences of being abroad, and after return, are mediated by exposure to different cultural environments. Addressing this conceptual and empirical gap, the paper analyses the experiences of New Zealand return migrants, or sojourners, who lived and worked in European countries (other than the UK) for more than one year and compares them with the experiences of NZ returnees from the UK. Drawing on 20 ‘non-UK’ and 22 ‘UK’ in-depth interviews, the paper revisits [Rhinesmith, 1975] and [Rhinesmith, 1986] typology of cross-cultural, or intercultural, adjustment (largely ignored in studies of return migration) to assess sojourners’ experiences throughout the migration cycle and serve as a useful tool for identifying and reporting psychological and socio-cultural elements in the returnees stories. The findings of sojourners’ possible identity shifts during intercultural transition are discussed with reference to the four-member paradigm of Cultural Identity Model (CIM) (Sussman, 2010) while addressing Sussman's (2002) argument that overseas adaptation and repatriation experiences are not directly associated. This paper demonstrates the need to understand first that the costs and benefits of circular migration or sojourning are country-specific, and that they do not ‘just happen’ at a particular moment or in one phase but are forged through a veritable rollercoaster of experiences of intercultural adjustment.  相似文献   
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