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21.
W. H. Chow C. C. Leung Y. L. Yip S. W. Mok H. W. Kui 《Metallurgical and Materials Transactions A》2013,44(8):3532-3543
Molten Fe79.5B6.5C14 melts can be cast into ingots of networklike microstructure. According to microstructural classification, a Fe79.5B6.5C14 network specimen can be divided into three zones. Zone A is occupied by a random network, zone B by a uniformly aligned network, and zone C by a severely aligned network that exhibits network patterns. 相似文献
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BACKGROUND: To examine the seasonality of suicides in Australia and New Zealand during the period 1981 to 1993. METHODS: A chi-square test and a harmonic analysis were used to detect the seasonality of the suicide data. RESULTS: The reduced amplitude and a smaller proportion of variance accounted for by seasonality suggested the seasonal effect on suicide is greatly diminished. The absence of biseasonal distribution of female suicides was also consistently found in the two countries. The finding was contrary to the reported results in seventies in many Western countries. CONCLUSIONS: The change in living condition, roles of males and females and communication pattern resulted in the reduction of climatic and environment effect in the seasonality of suicides were suggested. LIMITATIONS: The results would be better if a longer series of suicide date were available. 相似文献
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Abstract Two-level cumulative low-cycle fatigue lives of AISI 316 stainless steel notched specimens with different biaxial loading mode sequences were experimentally analyzed in this paper. Forty-eight cases were conducted in the experimental program by considering the loading level sequence effect, the biaxiality of two levels and the cycle ratios. Results show that interlock effect caused by the characteristic fracture surfaces of the different biaxial states is beneficial to the cumulative fatigue lives. On the other hand, the tensile loading of the second level will accelerate the opening of cracks and decrease fatigue strength. Miner's rule predicts most fatigue lives within 30% error bands, and the loading level sequence effect was not found in this research involving complex fracture modes. Fractography of specimens in the cumulative fatigue tests is reported and discussed in this paper. 相似文献
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Yip S 《Nature materials》2003,2(1):3-5
Should computational materials science be recognized as a field with a role in the community comparable to computational physics or chemistry? With the emergence of multiscale modelling, the answer is a resounding 'yes'. 相似文献
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Lately, the once powerful one-factor authentication which is based solely on either password, token or biometric approach, appears to be insufficient in addressing the challenges of identity frauds. For example, the sole biometric approach suffers from the privacy invasion and non-revocable issues. Passwords and tokens are easily forgotten and lost. To address these issues, the notion of cancellable biometrics was introduced to denote biometric templates that can be cancelled and replaced with the inclusion of another independent authentication factor. BioHash is a form of cancellable biometrics which mixes a set of user-specific random vectors with biometric features. In verification setting, BioHash is able to deliver extremely low error rates as compared to the sole biometric approach when a genuine token is used. However, this raises the possibility of two identity theft scenarios: (i) stolen-biometrics, in which an impostor possesses intercepted biometric data of sufficient high quality to be considered genuine and (ii) stolen-token, in which an impostor has access to the genuine token and used by the impostor to claim as the genuine user. We found that the recognition rate for the latter case is poorer. In this paper, the quantised random projection ensemble based on the Johnson–Lindenstrauss Lemma is used to establish the mathematical foundation of BioHash. Based on this model, we elucidate the characteristics of BioHash in pattern recognition as well as security view points and propose new methods to rectify the stolen-token problem. 相似文献
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Alberto Carlucci Martin Hooton Hj Mazlan Abd Salim Sammy Yip Kelvin Moneypenny Steve Kite 《Bautechnik》2015,92(3):220-226
The Temburong Bridge Project is a 30 km long dual two‐lane highway crossing over the Brunei Bay. It will connect the relatively isolated Brunei district of Temburong to the other three Brunei districts. The main objective of the project is to stimulate economic growth in the Temburong region by connecting it to the country's airport and ports. The alignment crosses two navigation channels resulting in the need for two cable stayed bridges – the Brunei Channel Bridge (145 m main span) and the Eastern Channel Bridge (260 m main span). The design of these cable stayed bridges is one of the first applications of the Eurocode to a fully concrete cable stayed bridge. Both cable stayed bridges draw on strong Islamic architectural influences from the region to form a tower shape that is unique and instantly recognisable. Temburong Brücke, Brunei – Entwurf von zwei Schrägkabelbrücken Die Temburong Brücke ist eine 30 km lange Verbindung über die Brunei Bucht mit zwei Richtungsfahrbahnen mit je zwei Fahrstreifen. Sie wird den relativ isolierten Distrikt Temburong mit den anderen drei Distrikten Bruneis verbinden. Hauptanliegen des Projekts ist die Stimulierung von ökonomischem Wachstum in der Temburong Region, indem sie an den Flughafen und Seehafen des Landes angebunden wird. Die Trassierung erfordert die Überquerung zweier Schiffahrtsrouten. Dies wird mit der Anordnung zweier Schrägkabelbrücken ermöglicht, der Brunei Channel Brücke (145 m Hauptspannweite) und der Eastern Channel Brücke (260 m Hauptspannweite). Die Bemessung der beiden Brücken stellt eine der ersten Anwendungen des Eurocode auf Schrägkabelbrücken mit Betonüberbau dar. Optisch sind die beiden Brücken geprägt von der islamischen Architektur der Umgebung, die Pylonform ist ein besonderes Erkennungsmerkmal der Brücken. 相似文献
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