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981.
Changgeng Liu Beatrice Pazzucconi Juan Liu Xincheng Yao 《Journal of Modern Optics》2019,66(12):1311-1317
We demonstrated the feasibility of using a holographic waveguide imager for eye tracking. A holographic waveguide placed in front of the eye was used to capture images of the anterior segment of the eye and to guide the images to a camera distant from the eye. The pupil centre (PC) and corneal reflection (CR) of the eye was used to compute eye position. A custom-built model eye was used to validate the prototype eye tracker. A linear relationship between the angular eye position and the PC/CR vector was found over 60 horizontal degrees and 40 vertical degrees. The tracking accuracy and precision were 0.72 degree and 0.50 degree over these tracking ranges. These results confirmed that holographic waveguide could be a viable platform for developing compact, wearable, see-through eye trackers that can continuously monitor eye movements during real life tasks and thus can facilitate diagnosis of oculomotor disorders. 相似文献
982.
Yanfeng Li Denghui Ji Shaopeng Liu Guide Tang Zhuangzhi Li Yuxi Yao Denglu Hou Minggang Zhu 《稀有金属(英文版)》2012,31(4):379-386
The fact that there are Mn2+ at the A sites in the ABO3 perovskite phase of manganites with the nominal composition La0.6-xNdxSr0.1MnO3 showed by detailed experimental study and theoretical calculations.The magnetic moments of these Mn2+ are antiparallel to those of the Mn ions at the B sites.The content of the Mn2+ increases as the average ionic radius,(rA),of the ions at A sites decreases,resulting in the experimentally observed phenomenon that the content of the Mn3O4 phase in the manganites decreases with decreasing 〈rA〉. 相似文献
983.
984.
A NEW COMPLEX SPHERE DETECTOR WITH SE ENUMERATION 总被引:1,自引:0,他引:1
985.
The synthesis of a new cholesteric monomer ( MLC) containing menthyl groups and a series of cholesteric elastomers ( LCE1−LCE4 ) is described. Their chemical structures and purity were characterized by FTIR, 1H-NMR, and elemental analyses. The phase behavior and thermal stability were investigated by differential scanning calorimetry, polarizing optical microscopy, X-ray diffraction, and thermogravimetric analysis. By inserting a flexible spacer between the mesogenic core and the terminal menthyl groups, mesomorphism of M LC was realized. LCE1−LCE4 with low content of crosslinking unit exhibited cholesteric phase because of the introduction of the nematic crosslinking unit. This indicates that low levels of chemical crosslinking do not significantly affect the phase behavior and mesomorphism of the elastomers, and reversible mesophase transitions can be observed. In addition, with increasing the content of crosslinking unit, the corresponding Tg decreased for LCE1−LCE4 , whereas their Ti did not remarkable change. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
986.
Ensemble of extreme learning machine for landslide displacement prediction based on time series analysis 总被引:2,自引:1,他引:1
Landslide hazard is a complex nonlinear dynamical system with uncertainty. The evolution of landslide is influenced by many factors such as tectonic, rainfall and reservoir level fluctuation. Using a time series model, total accumulative displacement of landslide can be divided into the trend component displacement and the periodic component displacement according to the response relation between dynamic changes in landslide displacement and inducing factors. In this paper, a novel neural network technique called ensemble of extreme learning machine (E-ELM) is proposed to investigate the interactions of different inducing factors affecting the evolution of landslide. Grey relational analysis is used to sieve out the more influential inducing factors as the inputs in E-ELM. Trend component displacement and periodic component displacement are forecasted, respectively; then, total predictive displacement is obtained by adding the calculated predictive displacement value of each sub. Performances of our model are evaluated by using real data from Baishuihe landslide in the Three Gorges Reservoir of China, and it provides a good representation of the measured slide displacement behavior. 相似文献
987.
988.
Shih‐Min Chang Erwin F. Rodríguez Tolava Yao‐Jhen Yang Hsin‐Chieh Li Rung‐Chuan Lee Nae‐Lih Wu Cheng‐Che Hsu 《Journal of the American Ceramic Society》2014,97(3):708-712
A one‐step process to fabricate crystalline Li4Ti5O12(LTO) particles directly from solution using an atmospheric pressure plasma jet (APPJ) is reported. This process uses Ti and Li ions‐containing salt solutions as the precursor, which is ultrasonically nebulized and then transported to the downstream of the APPJ using a carrier gas. With an extremely short contact time (<0.1 s) between the precursor droplets and the plasma jet, crystalline LTO can be fabricated in one step without additional rinse and postannealing steps. The LTO particle size can be effectively controlled using a preheater, the precursor solution composition and concentration, and the carrier gas flow rate. By properly adjusting the operating condition, particles of diameters from 100 nm to few μm with various morphologies can be obtained. When used as an electrode material, the resulting LTO powders fabricated under selected conditions show specific capacities over 100 mAh/g even at 50 C rate. 相似文献
989.
Qingshen Sun Fuying Wang Dequan Han Yao Zhao Zhidong Liu Hong Lei Yong Song Xue Huang Xiaodi Li Anyun Ma Guangyu Yuan Xueru Li Zaili Yang 《International Journal of Food Science & Technology》2014,49(5):1287-1293
This study was aimed to use soy protein isolate (SPI) and high methoxy pectin (HMP) as encapsulating materials for probiotic bacterial (Lactobacillus delbrueckii) delivery systems. The encapsulation conditions were optimised, and scanning electron microscopy (SEM) was used to characterise the microstructural changes of the microcapsule. The results showed that the optimal conditions for microcapsule preparation were 90 mg mL?1 SPI and 1 mg mL?1 HMP, with a SPI/HMP ratio of 7:1 (v/v), and a L. delbrueckii suspension to SPI–HMP complex ratio of 1:1 (v/v). The viability of the probiotics in the microcapsules reaching the small intestine was 3 log CFU mL?1 higher than that of naked bacteria. SEM showed that the surface of the SPI–HMP compound microcapsules was smooth and that a large number of L. delbrueckii could be seen in cross‐sections of the microcapsules. 相似文献
990.
Long‐term addition of micro‐amounts of hydrazine enhances nitrogen removal and reduces NO and NO3− production in a SBR performing Anammox 下载免费PDF全文