Mobile anchors are widely used for localization in WSNs.However,special properties over 3D terrains limit the implementation of them.In this paper,a novel 3D localization algorithm is proposed,called 3 DT-PP,which uti...Mobile anchors are widely used for localization in WSNs.However,special properties over 3D terrains limit the implementation of them.In this paper,a novel 3D localization algorithm is proposed,called 3 DT-PP,which utilizes path planning of mobile anchors over complex 3 D terrains,and simulations based upon the model of mountain surface network are conducted.The simulation results show that the algorithm decreases the position error by about 91%,8.7%and lowers calculation overhead by about 75%,1.3%,than the typical state-of-the-art localization algorithm(i.e.,'MDS-MAP','Landscape-3D').Thus,our algorithm is more potential in practical WSNs which are the characteristic of limited energy and 3D deployment.展开更多
A calibration procedure was developed for three-dimensional(3D) binocular structured light measurement systems. In virtue of a specially designed pattern, matching points in stereo images are extracted. And then suffi...A calibration procedure was developed for three-dimensional(3D) binocular structured light measurement systems. In virtue of a specially designed pattern, matching points in stereo images are extracted. And then sufficient 3D space points are obtained through pairs of images with the intrinsic and extrinsic parameters of each camera estimated prior and consequently some lights are calibrated by means of multi point fitting. Finally, a mathematical model is applied to interpolate and approximate all dynamic scanning lights based on geometry. The process of calibration method is successfully used in the binocular 3D measurement system based on structured lights and the 3D reconstruction results are satisfying.展开更多
Fe3C-functionalized three-dimensional （3D） porous nitrogen-doped graphite carbon composites （Fe3C/ NG） were synthesized via a facile solution-based impreg- nation and pyrolysis strategy using the commercially avai...Fe3C-functionalized three-dimensional （3D） porous nitrogen-doped graphite carbon composites （Fe3C/ NG） were synthesized via a facile solution-based impreg- nation and pyrolysis strategy using the commercially available melamine foam and FeC13 as precursors. The structural characterizations confirmed that Fe3C nanoparticles with an average core size about 122 nm were assembled on the surface of the carbonized melamine foam （CMF） skeletons. The electrochemical measurements demonstrated the superior electrocatalytic activity of the advanced Fe3C/NG composite for hydrogen peroxide reduction reaction in 0.1 mol/L PBS electrolyte and the limit of detection of H2O2 is estimated to be 0.035 mmol/L at a signal-to-noise ratio of 3 with a wide linear detection range from 50 μmol/L to 15 mmol/L （R^2 = 0.999）. Compared with the pure CMF, the Fe3C/NG exhibited higher catalytic activity, more stable response, lower detection limit, higher selectivity and a wider detection range, which could be attributed to the synergic effect between the two types of active sites from the iron carbide species and the nitrogen-doped graphite carbon. Meanwhile, the large surface area, high conductivity and the improved mass transport from the 3D porous material can also promote the electrochemical sensing performance. Moreover, the Fe3C/ NG-based electrochemical sensor showed high anti-interference ability and stability for H2O2 detection. Thus, the novel and low-cost Fe3C/NG composite may be a prom- ising alternative to noble metals and offer potential appli- cations in various types of electrochemical sensors, bioelectronic devices and catalysts.展开更多
Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level ...Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level of integration, random accessibility, and low-power operation. It needs to be installed with the cover glass in practical applications to protect the sensor from damage, mechanical issues,and environmental conditions, which, however, limits the accuracy and usability of the sensor due to the reflection in the optical path from air-to-cover glass-to-air. In this work, the flexible 3D nanocone anti-reflection(AR) film with controlled aspect ratio was firstly employed to reduce the light reflection at air/cover glass/air interfaces by directly attaching onto the front and rear sides of the CIS cover glass.As both the front and rear sides of cover glass were coated by the AR film, the output image quality was found to be improved with external quantum efficiency increased by 7%, compared with that without AR film. The mean digital data value, root-mean-square contrast, and dynamic range are increased by45.14%, 38.61% and 57, respectively, for the output image with AR films. These results provide a novel and facile pathway to improve the CIS performance and also could be extended to rational design of other image sensors and optoelectronic devices.展开更多
基金Supported by the Important National Science and Technology Specific Project of China(No.20112X03002-002-03)the National NatureScience Foundation of China(No.61133016,61163066)
文摘Mobile anchors are widely used for localization in WSNs.However,special properties over 3D terrains limit the implementation of them.In this paper,a novel 3D localization algorithm is proposed,called 3 DT-PP,which utilizes path planning of mobile anchors over complex 3 D terrains,and simulations based upon the model of mountain surface network are conducted.The simulation results show that the algorithm decreases the position error by about 91%,8.7%and lowers calculation overhead by about 75%,1.3%,than the typical state-of-the-art localization algorithm(i.e.,'MDS-MAP','Landscape-3D').Thus,our algorithm is more potential in practical WSNs which are the characteristic of limited energy and 3D deployment.
基金The National Natural Science Foundation of China (No30470488)
文摘A calibration procedure was developed for three-dimensional(3D) binocular structured light measurement systems. In virtue of a specially designed pattern, matching points in stereo images are extracted. And then sufficient 3D space points are obtained through pairs of images with the intrinsic and extrinsic parameters of each camera estimated prior and consequently some lights are calibrated by means of multi point fitting. Finally, a mathematical model is applied to interpolate and approximate all dynamic scanning lights based on geometry. The process of calibration method is successfully used in the binocular 3D measurement system based on structured lights and the 3D reconstruction results are satisfying.
基金supported by the National Natural Science Foundation of China (21275136)the Natural Science Foundation of Jilin Province (201215090)
文摘Fe3C-functionalized three-dimensional （3D） porous nitrogen-doped graphite carbon composites （Fe3C/ NG） were synthesized via a facile solution-based impreg- nation and pyrolysis strategy using the commercially available melamine foam and FeC13 as precursors. The structural characterizations confirmed that Fe3C nanoparticles with an average core size about 122 nm were assembled on the surface of the carbonized melamine foam （CMF） skeletons. The electrochemical measurements demonstrated the superior electrocatalytic activity of the advanced Fe3C/NG composite for hydrogen peroxide reduction reaction in 0.1 mol/L PBS electrolyte and the limit of detection of H2O2 is estimated to be 0.035 mmol/L at a signal-to-noise ratio of 3 with a wide linear detection range from 50 μmol/L to 15 mmol/L （R^2 = 0.999）. Compared with the pure CMF, the Fe3C/NG exhibited higher catalytic activity, more stable response, lower detection limit, higher selectivity and a wider detection range, which could be attributed to the synergic effect between the two types of active sites from the iron carbide species and the nitrogen-doped graphite carbon. Meanwhile, the large surface area, high conductivity and the improved mass transport from the 3D porous material can also promote the electrochemical sensing performance. Moreover, the Fe3C/ NG-based electrochemical sensor showed high anti-interference ability and stability for H2O2 detection. Thus, the novel and low-cost Fe3C/NG composite may be a prom- ising alternative to noble metals and offer potential appli- cations in various types of electrochemical sensors, bioelectronic devices and catalysts.
基金financially supported by the National Natural Science Foundation of China(61474128,21503261,61504155and 61404145)Youth Innovation Fund for Interdisciplinary Research of SARI(Y526453233,141004)+2 种基金Science & Technology Commission of Shanghai Municipality(14JC1492900,14511102302,15DZ1100502)Youth Innovation Promotion Association,CAS(2013302)Development Fund for Information communication and integrated circuit technology public service platform(No.2016-14)supported by Zhangjiang Adminstrative Committee
文摘Complementary metal oxide semiconductor(CMOS) image sensors(CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera(DSLR), smart phones and so on, owing to their high level of integration, random accessibility, and low-power operation. It needs to be installed with the cover glass in practical applications to protect the sensor from damage, mechanical issues,and environmental conditions, which, however, limits the accuracy and usability of the sensor due to the reflection in the optical path from air-to-cover glass-to-air. In this work, the flexible 3D nanocone anti-reflection(AR) film with controlled aspect ratio was firstly employed to reduce the light reflection at air/cover glass/air interfaces by directly attaching onto the front and rear sides of the CIS cover glass.As both the front and rear sides of cover glass were coated by the AR film, the output image quality was found to be improved with external quantum efficiency increased by 7%, compared with that without AR film. The mean digital data value, root-mean-square contrast, and dynamic range are increased by45.14%, 38.61% and 57, respectively, for the output image with AR films. These results provide a novel and facile pathway to improve the CIS performance and also could be extended to rational design of other image sensors and optoelectronic devices.
