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31.
利用多尺度模拟方法针对Al-Cu合金近液相线半连续铸造的特点,建立了描述成形过程的温度场模型、液固相变模型,通过固相率变化将宏观尺度的温度场和介观尺度的微观组织模拟耦合起来,利用有限差分法和元胞自动机法对Cu质量分数分别为4%、4.5%及5%的Al-Cu合金近液相线铸造进行了组织演变的模拟。模拟了上述合金在浇铸温度为液相线温度以上7~25 K、铸造速度为1.5~3.5 mm/s、水冷系数为1 000~2 000 W/(m2.K)的液相线铸造中的组织演变,与ZL201合金的实验吻合。计算表明,当Al-Cu合金中Cu质量分数为5%、浇注温度为930 K、水冷系数为1 000 W/(m2.K)、铸造速度为2 mm/s时,获得的微观组织均匀、细小。 相似文献
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After 104 h of continuous aqueous electrolysis with K2CO3 as the electrolyte, highly stable novel inorganic hydride compounds such as KH KHCO3 and KH were isolated and identified by time of flight secondary ion mass spectroscopy (ToF-SIMS). The existence of novel hydride ions was determined using X-ray photoelectron spectroscopy (XPS) and solid state magic-angle spinning proton nuclear magnetic resonance spectroscopy (1H MAS NMR). A novel hydride ion formed by plasma electrolysis of a K2CO3, Rb2CO3, or Cs2CO3 electrolyte was also observed by high resolution visible spectroscopy at 407.0 nm corresponding to its predicted binding energy of 3.05 eV. 相似文献
34.
为了解决小麦蛋白质的近红外光谱信息复杂、共线性严重及全光谱建模的预测能力不足等问题,采用一种新的变量选择方法——变量组合集群分析法(VCPA)对小麦蛋白质的近红外光谱进行特征波长选取.首先利用二进制矩阵采样策略(BMS)和指数衰减函数(EDF)删除无信息变量,优选小麦中蛋白质近红外特征波长,然后结合偏最小二乘法(PLS)建立预测模型.与其他变量选择方法相比,VCPA所选用的波长点最少,模型的预测能力最强,VCPA算法所采用的BMS变量采样策略弥补了蒙特卡洛采样方法的不足.研究结果表明,VCPA算法可以有效选择小麦蛋白质近红外光谱特征波长,提高预测模型的可靠性和适用性. 相似文献
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In this work, we discuss a recently proposed approach for supervised dimensionality reduction, the Supervised Distance Preserving Projection (SDPP) and, we investigate its applicability to monitoring material's properties from spectroscopic observations. Motivated by continuity preservation, the SDPP is a linear projection method where the proximity relations between points in the low-dimensional subspace mimic the proximity relations between points in the response space. Such a projection facilitates the design of efficient regression models and it may also uncover useful information for visualisation. An experimental evaluation is conducted to show the performance of the SDPP and compare it with a number of state-of-the-art approaches for unsupervised and supervised dimensionality reduction. The regression step after projection is performed using computationally light models with low maintenance cost like Multiple Linear Regression and Locally Linear Regression with k-NN neighbourhoods. For the evaluation, a benchmark and a full-scale calibration problem are discussed. The case studies pertain the estimation of a number of chemico-physical properties in diesel fuels and in light cycle oils, starting from near-infrared spectra. Based on the experimental results, we found that the SDPP leads to parsimonious projections that can be used to design light and yet accurate estimation models. 相似文献
37.
The APP (Application) store at the Android market is very popular and attractive for most of current smart phone users. A rotary ring type of APP named as Loving SML (Loving Sun-Moon Lake--"爱上日月谭") is an instant information capturer to capture the instant traffic tourism information (info) services and serve as an interactive device for user to know the instant traffic information of SML area where you may want to go. The tourism service is specialized on i3 travel, which is identified as innovation, intelligent, and interesting for all of the visitors coming from all over the world. The captured instant information is provided by the sightseeing cloud from SML-NSA (National Scenic Area) with the integration of infrastructure of VD (vehicle detector), CMS or VMS (changeable (or variable) message sign), CCTV (closed circuit television), AVI (automatic vehicle identification). The technique of AR (augmented reality) is also used to identify how many sparkling places in front of you that you may visit. One can easily know the road performance ahead from you before you plan a trip. 相似文献
38.
本文设计一个基于多点触摸、手势识别等技术的新型投影系统,通过摄像头捕捉手指触摸或激光笔照射投影屏幕时所反射的红外光,将信息传递到图像处理模块,并对其进行多点定位和分析,判断出旋转、缩放等操作意图后,将处理结果以标准形式传输到相应的应用程序,并做出相应的操作。系统构建所需的设备简单、价格低廉。测试结果显示:系统反应灵敏,能满足应用需求。 相似文献
39.
In occupational safety and health, big data and analytics show promise for the prediction and prevention of workplace injuries. Advances in computing power and analytical methods have allowed companies to reveal insights from the “big” data that previously would have gone undetected. Despite the promise, occupational safety has lagged behind other industries, such as supply chain management and healthcare, in terms of exploiting the potential of analytics and much of the data collected by organizations goes unanalyzed. The purpose of the present paper is to argue for the broader application of establishment-level safety analytics. This is accomplished by defining the terms, describing previous research, outlining the necessary components required, and describing knowledge gaps and future directions. The knowledge gaps and future directions for research in establishment-level analytics are categorized into readiness for analytics, analytics methods, technology integration, data culture, and impact of analytics. 相似文献
40.
By multi-stage rod-in-tube fiber drawing process, a single-mode fluorotellurite glass fiber was fabricated and reported for the first time. Benefiting from chemical–physical dehydration process to remove water and OH− groups, the propagation loss was decreased to 1.9 dB/m at 1550 nm and the infrared window is extended from 2.8 μm to 4.2 μm, i.e. a new kind of mid-infrared glass fiber. The fiber is with a small core of 3.52 μm in diameter to meet single-mode condition, and the effective nonlinear parameter γ was estimated to be 236.7 W−1 km−1 at 1550 nm by using continuous-wave self-phase modulation method. © 2015 Elsevier B.V. All rights reserved. 相似文献