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61.
针对目标估计过程需要大量人工参与、自动化程度低的问题,提出了基于数据质量评价的目标估计方法。利用目标数据质量评价方法,对不同传感器得到的目标数据质量进行科学、有效的测度和评价,并根据质量得分动态调整各数据源在目标估计过程中所占的权重,从而减少人工干预,提高目标估计效能。仿真试验结果证明了该方法的有效性。 相似文献
62.
Deposition temperature effect on sputtered hydroxyapatite coatings prepared on AZ31B alloy substrate
《Ceramics International》2022,48(8):10486-10497
The corrosion of Mg alloys is a provocative topic and it is still a challenge to find a solution for the improvement of their degradation rate into solution found in human body (Simulated Body Fluid, SBF). The aim of the present paper is to coat AZ31B alloy by hydroxyapatite (HAp) as a possible solution in order to change its degradation behaviour for medical implants. Since the Mg alloy is sensible to temperature while the HAp properties depend on the deposition temperature, in this study, the effect of deposition temperature on the properties of the AZ31Balloy was evaluated. The HAp coatings were prepared using the RF magnetron sputtering technique, ranging the temperature from the room one to 400 °C. It was found that the grain size of the investigated Mg alloy increased more than 100% when the deposition temperature was increased. By increasing the temperature, the hardness level was reduced of about 15%. All HAp coatings revealed corrosion behaviour much better than the uncoated AZ31B alloy; in particular, the coating deposited at 200 °C exhibited the best corrosion behavior. Moreover, the best protection to the corrosive attack of SBF was found for the HAp coating deposited at 200 °C (97.3%), which was also characterized by the lowest porosity. To conclude, HAp coatings can be used to improve the properties of AZ31B alloys, but just up to 200 °C; beyond this temperature, the mechanical and the anticorrosion properties are lost. 相似文献
63.
《Ceramics International》2022,48(14):20194-20200
In this paper, TCO (Transparent Conductive Oxide) incorporating ultrathin Ag intermediate film is proposed as a new buffer layer to enhance the efficiency of CIGS thin-film solar cells (TFSCs). In this regard, versatile multilayer thin-films based on ZnO/Ag/ZnO and ITO/Ag/ITO structures were deposited on glass using RF magnetron sputtering technique to determine the optoelectronic parameters of the multilayer structures. The elaborated samples were then characterized using SEM, EDS, XRD, and UV–Visible absorption spectroscopy techniques to investigate the structure morphological, optical, and electronic properties. The deposited multilayer thin-films showed amorphous-like structure and exhibited a broadband absorbance over the visible and even NIR spectrum ranges, indicating its potential application as alternative buffer layers for thin-film solar cells. In this context, TCO/Ag/TCO/CIGS solar cells have been numerically investigated using the deposited multilayer optoelectronic properties. It was revealed that the estimated efficiency of the ZnO/Ag/ZnO/CIGS-based solar cell could reach 18.5% with an open circuit voltage of 0.7 V and a short-circuit current density of 34.8 mA/cm2. The performances exhibited by the investigated solar cell demonstrated that ZnO/Ag/ZnO multilayer can be used as an alternative to the conventional CdS buffer layer for developing high-performance non-toxic CIGS solar cells. 相似文献
64.
65.
Xunwang Shi Xiuhan Yu Caiwen Nie Fengji Li Sam Zhang 《Ceramics International》2021,47(15):21546-21553
Color films are widely used for visual effect as well as for their functional properties. To date, however, synthesizing thin films with desired color remains challenging. In this work, AlN color films are deposited on Si wafers by precise control of the deposition time for different thickness during reactive magnetron sputtering from an Al target in Ar/N2 atmosphere. The thickness, morphology, structure, composition and color index are carefully examined by field emission scanning electron microscopy, atomic force microscopy, grazing incidence X-ray diffraction, X-ray photoelectron spectrometry and colorimeter, respectively. As the film thickness changes from 57 nm to 165 nm, the film exhibits purple, indigo, blue, green, yellow, orange and red in color. These colors repeat in the same order when the thickness goes over 165 nm. Once the thickness exceeds 467 nm, overlapping of colors takes place. The mechanisms are elucidated. 相似文献
66.
Jianwei Qi Fengkai Xu Kang Bao Peixuan Li Danfeng He Kai Chen Qingliang Wang 《Journal of the European Ceramic Society》2021,41(6):3731-3742
The nanostructured diamond-like carbon/hydroxyapatite composite coating (DLC/HA) was deposited using magnetron sputtering technique with a densely packed columnar cross-sectional structure and a uniform granular surface morphology. After heat treatment, the amorphous structure of the coating was transformed into a crystal structure. Nanohardness and scratch tests results demonstrated the DLC transition layer significantly enhanced the nanohardness of Ti6Al4V substrates from 4.8 GPa to 10.4 GPa, and increased critical load from 16.6 N (pure HA layer) to 26.5 N (DLC layer) without obvious brittle fracture, flaking and delamination. Electrochemical and immersion tests results demonstrated that DLC/HA composite coatings with a dense gradient transition interlayer had better corrosion resistance and could prevent harmful metal ions being released into the SBF solution more effectively than single HA coatings. Furthermore, active Ca2+ ions can be rapidly released from the coating surface during initial immersion in the SBF solution, and facilitated the formation of bone-like apatite. 相似文献
67.
在单光子计数激光雷达检测领域,目前的检测方法在低信噪比情况下虚警概率会增加,同时也无法适应噪声变化的问题。针对这些问题,提出了一种基于Bayesian的检测方法,该方法首先通过雷达方程估计回波信号光子数的范围,将其作为先验信息,而后结合二项分布建立了累计概率模型,基于Bayesian判决准则计算得到检测阈值,此阈值能够在检测概率与虚警概率中间择其平衡。这种方法不仅克服了低信噪比检测困难的情况,还减少了先验信息的获取难度。实验结果表明,对比固定阈值其虚警概率降低了10倍。对比“恒虚警”其检测概率提高了约20。验证了方法具有良好的检测效果,具备一定的可操作性。 相似文献
68.
Arzu Karataş 《International Journal of Food Science & Technology》2022,57(3):1429-1439
The use of agro-industrial waste as substrates for mushroom cultivation is considered a promising management strategy for reducing and valorising these wastes, simultaneously reducing the cost of mushroom cultivation. In this study, oyster mushroom Pleurotus ostreatus were cultivated on twelve substrates composed of either tea waste, lime sawdust, alder sawdust, hornbeam sawdust/shaving, wheat stalk-straw, wheat bran or their composite to determine the proximate composition and accumulation of thirteen elements in their fruiting bodies. The proximate composition of P. ostreatus did not show a significant difference, regardless of the employed substrate. (one-way manova ; F(66, 107) = 1.329, Wilk’s λ = 0.041, P > 0.05). However, their chemical element contents show a statistically significant difference (one-way manova ; F(132, 418) = 32.163, Wilk’s λ = 0.000, P < 0.05). These results were supported by discriminant function and principal component analyses. The highest mean concentrations of six of twelve elements (i.e., Ca, Mg, Na, Zn, Cd and Cr) were recorded in P. ostreatus cultivated on the lime-sawdust substrate. Three health indices viz., estimated daily intake, target hazard quotient (THQ) and total THQ were applied to determine the risk to human health via the consumption of P. ostreatus, suggesting that they are safe for human consumption. 相似文献
69.
应用型本科是高等教育转型发展的产物,对普通本科教育是一种必要的补充。本文分析了《微生物学》教学工作者在应用型本科的前提下如何进行准确的课程目标定位,并探索了与之适应的任务驱动式教学模式。结果表明:任务驱动式教学能有效执行应用型本科《微生物学》课程目标定位,极大提高学生学习的积极性和主动性,取得良好的教学效果力。 相似文献
70.
阐述了采用真空磁控溅射原理生产双银Low-E镀膜玻璃膜系的一种新的开发思路,通过对双银Low-E膜系的实际开发过程分析,提出了双银Low-E镀膜玻璃膜系的开发过程中应注意的问题,并对实际生产提供了指导性建议。 相似文献