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51.
First-principles calculations were employed to study the migration of vacancy in clean and Si-doped Al3Ti. The effect of Si doping on the formation of vacancy and the diffusion of doped-Si atom in the Al3Ti were also investigated. It is found that, under Al-rich condition, the formation energies of Al vacancies in Al3Ti with Si doping are decreased compared with those in clean Al3Ti. The preferred migration paths of vacancies are not changed when Si occupies Al site, but the migration energy barriers for the majority of paths are decreased after Si doping. The doped-Si atom on Al site prefers to diffuse via the nearest Al vacancy.  相似文献   
52.
Energy cultures: A framework for understanding energy behaviours   总被引:1,自引:0,他引:1  
Achieving a ‘step-change’ in energy efficiency behaviours will require enhanced knowledge of behavioural drivers, and translation of this knowledge into successful intervention programmes. The ‘Energy Cultures’ conceptual framework aims to assist in understanding the factors that influence energy consumption behaviour, and to help identify opportunities for behaviour change. Building on a history of attempts to offer multi-disciplinary integrating models of energy behaviour, we take a culture-based approach to behaviour, while drawing also from lifestyles and systems thinking. The framework provides a structure for addressing the problem of multiple interpretations of ‘behaviour’ by suggesting that it is influenced by the interactions between cognitive norms, energy practices and material culture.  相似文献   
53.
54.
Objective: To assess the effects of expressive writing on health care utilization, clinical variables and subjective quality of life following first myocardial infarction (MI). Methods: One-hundred and seventy-nine first MI patients were randomized to Intervention (N = 88) or Control (N = 91) groups. The intervention group wrote about their thoughts and feelings in relation to having had an MI. Controls wrote in a neutral way about daily activities. The main outcome measures were health care utilization, physical status and subjective quality of life (QOL), assessed after one, two, and five months. Results: One-hundred and fifty-six (87%) completed the study. Five months post-intervention, the intervention group had significantly fewer recorded medical appointments compared to controls. The number of prescribed medicines decreased over time within the intervention group but increased within the control group. The intervention group attended significantly more rehabilitation sessions, reported fewer cardiac related symptoms and had lower diastolic blood pressure five months post-intervention. There was no significant group by time interaction on reported physical health. The group by time interaction on reported mental health approached significance, those in the intervention group reporting greater improvement. Conclusion: Expressive writing may be a beneficial strategy which could be incorporated into rehabilitation interventions to help individuals adjust after first MI. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
55.
在最近几年中,D类放大器因其体积小,效率高,已经进入了消费类音频电子产品、汽车以及便携式音频产品市场.它的效率帮助减小了汽车放大器以及便携式媒体扩展插槽的尺寸,并以较小的波形因子提供了更大的功率,有助实现新式的消费类音频设备.  相似文献   
56.
So far the literature on inventory control for perishable products has mainly focused on (near-) optimal replenishment policies for a stylized environment, assuming no lead-time, no lot-sizing, stationary demand, a first in first out withdrawal policy and/or product life time equal to two periods. This literature has given fundamental insight in the behavior and the complexity of inventory systems for perishable products. In practice, many grocery retailers have recently automated the inventory replenishment for non-perishable products. They recognize they may need a different replenishment logic for perishable products, which takes into account e.g. the age of the inventory in the system. Due to new information technologies like RFID, it now also becomes more economically feasible to register this type of information. This paper suggests a replenishment policy for perishable products which takes into account the age of inventories and which requires only very simple calculations. It will be shown that in an environment, which contains important features of the real-life retail environment, this new policy leads to substantial cost reductions compared with a base policy that does not take into account the age of inventories.  相似文献   
57.
The impact of removing the rind from fresh‐cut watermelon slices was assessed on the quality of the product during storage at 4 °C for 9 days. Flesh lycopene declined from 55.4 to 47.9 mg kg?1 f.w. and colour lightness (L*) increased from 43.2 to 45.8 after 2 days of storage. Initial heart and placental flesh firmness increased from 7.3 and 9.8 N, respectively, to 9.5 and 12.8 N after 9 days, but were unaffected by rind processing. Electrolyte leakage from placental tissue was unaffected by storage and rind. Rind presence limited juice run‐off by 47.2% and maintained mean total soluble sugar concentration in the slices at 86.0 mg mL?1 as opposed to 76.8 mg mL?1 in rind‐less slices. Change in the quality was most pronounced between 0 and 2 day of storage. Removing the rind accelerated senescence and off‐flavour production, while the presence of rind improved the overall storage stability of fresh‐cut watermelon slices.  相似文献   
58.
We describe the challenges faced when developing a Linux/PC-based cluster to apply bioinformatics algorithms to the rapidly increasing raw genomics data available. The calculations, which take around two months to complete, result in a powerful resource that can be used for data mining--most obviously for the human genome. Our current infrastructure consists of a 1314 node cluster with 1734 processors supporting both production and research. This paper highlights the problems in achieving high data throughput with such systems and shows that raw computer power is only one component of a complex problem.  相似文献   
59.
Prior meta-analytic evidence has indicated no association between relationship length and perceived trustworthiness. Viewing trustors as information processors, the authors propose a model in which relationship length, although having no direct effect on perceived trustworthiness, moderates the association between perceived trustworthiness and the basis on which people decide to trust each other. Specifically, as trustors learn about others, they base their trust on different kinds of information (demographic similarity, trustworthy behavior, and shared perspective). Hierarchical multiple regression analyses of a field survey of supervisors and subordinates from 3 companies (N = 88) provide evidence consistent with this prediction: Perceived trustworthiness is associated with demographic similarity in newer relationships, with trustworthy behavior in relationships that are neither brand new nor old but in-between, and with shared perspective in older relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
This talk takes you behind the scenes at Pixar Animation Studios for an in‐depth look at how its 3d computer graphics films are made. Making a computer animated film involves people with artistic talent and people with technical skills working together in close collaboration. The process starts with the development of the story and continues with modeling the geometry, adding articulation controls, using those controls to animate the characters, simulating things like water and cloth and hair, defining the look of the surfaces, putting lights in the scene, adding special effects, rendering, and post‐production. Special emphasis is given to the roles of technology and computer graphics research in supporting the filmmaker.  相似文献   
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