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41.
《Ceramics International》2020,46(6):7122-7130
This study examines three novel approaches for enhancing the thermoelectric (TE) properties of atomic-layer-deposited (ALD) ZnO thin films: 1) Hf-doping, which preserved the crystallinity of ZnO and provided effective phonon scattering owing to Hf's similar atomic radius to and large mass difference with Zn, leading to high power factor (PF) and low thermal conductivity (κ); 2) controlling the distribution of Hf into an alternating scattered phase/clustered phase superlattice, which balanced the high PF of the scattered phases with the low κ of the clustered phases, while providing significant energy-filtering effect to raise the Seebeck coefficient; 3) introducing 18O/16O periodicity into the Hf:ZnO films—by alternately using H216O and H218O as oxidants in the ALD processes, which further suppressed κ without compromising PF. The combination of the three approaches resulted in a maximum improvement in ZT of ~1600% over that of the undoped ZnO.  相似文献   
42.
本文建立了PC结构施工全过程的BIM模型及有限元分析模型,对施工过程进行数值模拟与动态、静态监测,对装配式结构进行了结构性能评价,为结构可视化施工监测提供了技术支持。  相似文献   
43.
随着社会的发展,信息和文化资源大多来自于图书和网络,而高校图书馆有着丰富的藏书和网络资源,因此,高校图书馆网络资源的共建共享就是科学文化发展的必然结果。那么如何实现网络资源的共建共享,网络资源的共建共享又存在哪些问题,又该如何解决,本文在这里就简单的浅谈一下高校图书馆的资源共享。  相似文献   
44.
Evidence suggests that transient visual information, such as animations, may be more challenging to learn than static visualizations. However, when a procedural-manipulative task is involved, our evolved embodied cognition seems to reverse this transitory challenge. Hence, for object manipulative tasks, instructional animations may be more suitable than statics. We investigated this argument further by comparing animations with statics using a Lego task shown to university students, by examining three potential moderators of effectiveness: (a) the environment of manipulation (virtual or physical), (b) the quality of visual information (focused or unfocused), and (c) the presence of hands (no hands or with hands). In Experiment 1 we found an advantage of animation over statics, and no differences among the environments. In Experiment 2, we again observed an animation advantage, a small advantage of focused static information compared to unfocused static information, and a positive effect of not showing the hands.  相似文献   
45.
Animal groups in nature often display an enhanced collective information-processing capacity. It has been speculated that natural selection will tune this response to be optimal, ensuring that the group is reactive while also being robust to noise. Here, we show that this is unlikely to be the case. By using a simple model of decision-making in a dynamic environment, we find that when individuals behave rationally and are subject to selection based on their accuracy, optimality of collective decision-making is not attained. Instead, individuals overly rely on social information and evolve to be too readily influenced by their neighbours. This is due to a classic evolutionary conflict between individual and collective interest. The result is a sub-optimal system that is poised on the cusp of total unresponsiveness. Individuals in the evolved group exhibit delayed reactions to changes in the environment, before responding with rapid, socially reinforced transitions, reminiscent of familiar human and animal social systems (markets, stampedes, fashions, etc.). Our results demonstrate that behaviour of this type may not be pathological, but instead could represent an evolutionary attractor for such collective systems.  相似文献   
46.
为提高随钻测量系统的姿态估计精度,克服传统算法对于非平稳信号处理的局限性,提出基于ARIMA模型的卡尔曼滤波算法。该算法采用时间序列分析方法,建立了随机漂移误差的ARIMA模型,根据实测数据的ACF和PACF,确定微机械陀螺仪模型的各个参数,利用卡尔曼滤波算法进行滤波处理。实验对模型的拟合残差均值与方差作了比较分析,通过卡尔曼滤波处理,ARIMA模型数据零偏减小了1个数量级,滤波方差相比传统AR模型减小了42%。所建立的ARIMA模型与传统时间序列方法建模相比,降低了模型预测误差,滤除MEMS陀螺仪随机漂移误差更为明显,模型对提高陀螺仪输出精度更为有效。  相似文献   
47.
A new approach of frequency shifting by rotating kernel is proposed to improve the performance of a spatial filtering velocimeter, used to provide accurate velocity information for a vehicle self-contained navigation system. A linear CMOS image sensor was employed both as a spatiotemporal differential spatial filter and as a photodetector. The filtering operation was fully performed in FPGA and is realized by applying a rotating kernel to the pixel values of the image. Theoretical analysis showed this method could double the maximum measurable velocity. The power spectrum of the output signal was obtained by fast Fourier transform (FFT), and was corrected by a frequency spectrum correction algorithm, named energy centrobaric correction. This velocimeter was used to measure the moving velocities of a conveyor belt. Experimental results verified the method’s ability of reducing the output signal frequency and standard uncertainty of velocity measurement. What is more, the undesired output introduced by frequency shifting to the power spectrum of the output signal was deeply investigated and a new method was proposed to eliminate the undesired component in output signals. This velocimeter aims at providing accurate velocity information for vehicle autonomous navigation system.  相似文献   
48.
论文从硬件设备、软件服务、数据资源和任务调度等几个方面对美国海军在开发构建全舰计算环境基础设施过程中标准化的设计方法进行深入分析。通过采用标准化的计算、显示、存储等硬件资源并进行整合,提升硬件资源的利用效率和共用水平;开发各个层次的公共应用功能软件并形成标准化的服务,将软件和硬件解耦,达到应用与数据分离,使得基于TSCEI的信息化装备的构建更加快速灵活,开放性更好,可扩展性及升级能力大为增强。标准化在 TSCEI的推行和实施中起着至关重要的作用。标准化设计方法对构建我军新型信息基础设施具有较重要的借鉴作用。  相似文献   
49.
如今我国信息化技术全面发展,尤其对于工程测量工作领域来讲,不管是在工程建设和管理方面都产生不小的支撑引导效用。由此,笔者具体结合如今工程建设信息化测绘核心任何以及设备布置细节,进行结构整体安全管理周期和周边地理空间信息技术发展能效整理解析,试图将工程测量最新发展机遇和技术挑战问题处理完全。希望能够借此为日后一定时期范围内相关工程测量规划主体提供合理指导性建议内容,最终为我国各类工程事业可持续发展前景绽放奠定深刻适应基础。  相似文献   
50.
The objective of this study was to investigate the impact of functional labelling on the consumers acceptability and purchase intentions of blueberry functional beverages (BFB). A 2‐day consumer acceptance test was conducted independently with functional information (n = 60) and without any information (n = 80). The presence of functional labelling did not influence the liking attributes of BFBs (P > 0.05). However, functional information positively affected consumer perception of health‐related perceptions associated with BFBs, such as ‘aiding eye health improvement’ and ‘eye fatigue relief’. Subjects perceived more health‐related perceptions when informed test was conducted. The first‐order effect was observed, in which the degree of the first‐order effect was greater for BFBs that had a thicker mouthfeel. Findings from the results can practically guide product developers and marketers in the functional drink industry by providing the strategy for how to evaluate reformulated functional beverages for the consumer acceptance test by warning a counter‐balanced sample presentation.  相似文献   
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