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81.
Researchers have been closely studying how information technology services became a routine part of our lives. Studies have found that users who routinely use online services either consciously develop loyalty or automatically develop a habit. But many studies now mix the elements of conscious and automatic use despite the great differences in these phenomena. This study proposes a new theoretical framework of how the conscious and automatic mechanisms simultaneously, but differentially, regulate postadoption phenomena in the context of online information services. An empirical test confirms that these two mechanisms have highly discernible patterns that researchers and managers alike must heed.  相似文献   
82.
When used as floor joists, the new mono-symmetric LiteSteel beam (LSB) sections require web openings to provide access for inspections and various services. The LSBs consist of two rectangular hollow flanges connected by a slender web, and are subjected to lateral distortional buckling effects in the intermediate span range. Their member capacity design formulae developed to date are based on their elastic lateral buckling moments, and only limited research has been undertaken to predict the elastic lateral buckling moments of LSBs with web openings. This paper addresses this research gap by reporting the development of web opening modelling techniques based on an equivalent reduced web thickness concept and a numerical method for predicting the elastic buckling moments of LSBs with circular web openings. The proposed numerical method was based on a formulation of the total potential energy of LSBs with circular web openings. The accuracy of the proposed method's use with the aforementioned modelling techniques was verified through comparison of its results with those of finite strip and finite element analyses of various LSBs.  相似文献   
83.
Commercial and research work in the field of software defined radio (SDR) has produced designs which have been able to deliver the efficiency and computational power needed to process 3G wireless technologies. Though efficient 3G processing has been achieved by these designs, next generation 4G SDR technology requires 10–1000x more computational performance but limits the power budget increase to 2–5x. In this paper, we present a breakdown of the major 4G kernels and analyze two methods of increasing performance and reducing power consumption. Specifically, we consider the effect of SIMD width and reduction in number of register file accesses on the performance and energy consumption of a SDR architecture, SODA. We show that by increasing SIMD width we can gain almost 2–8x performance increase while increasing total energy used by 1–2x for different SIMD widths. We also show that by reducing SIMD register accesses we can reduce the total energy used by 5–20% for the 4G kernels.  相似文献   
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Microstructural evolution during directional solidification (DS) of Ni-base superalloy IN792+Hf has been investigated with an emphasis on theγ′precipitates and MC-type carbides.The quantitative image analyses revealed that the increase in the solidification rate up to 100μm/s at constant thermal gradient of 178 K/cm resulted in a fine and uniform distribution ofγ′precipitates.The relationship between the as-castγ′size and cooling rate was also determined for DS IN792+Hf.In the mean time,the MC carbide size was found to be dependent both on the solidification rate and the S/L interface morphology while the area fraction of MC carbide was significantly influenced by the S/L interface morphology.  相似文献   
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Capacitive deionization (CDI) for removal of water hardness was investigated for water softening applications. In order to examine the wettability and pore structure of the activated carbon cloth and composites electrodes, surface morphological and electrochemical characteristics were observed. The highly wettable electrode surface exhibited faster adsorption/desorption of ions in a continuous treatment system. In addition, the stack as well as unit cell operations were performed to investigate preferential removal of the hardness ions, showing higher selectivity of divalent ions rather than that of the monovalent ion. Interestingly, competitive substitution was observed in which the adsorbed Na ions were replaced by more strongly adsorptive Ca and Mg ions. The preferential removal of divalent ions was explained in terms of ion selectivity and pore characteristics in electrodes. Finally, optimal pore size and structure of carbon electrodes for efficient removal of divalent ions were extensively discussed.  相似文献   
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Journal of Mechanical Science and Technology - In this paper, to help reduce the squeal noise produced during the braking of urban railway vehicles, the shape of the disc brake pad was investigated...  相似文献   
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