2021
2021
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Record 265 of
Title:On-line SERS detection of adenine in DNA based on the optofluidic in-fiber integrated GO/PDDA/Ag NPs
Author(s):Gao, Danheng(1); Yang, Xinghua(1); Teng, Pingping(1); Kong, Depeng(2); Liu, Zhihai(1); Yang, Jun(1); Luo, Meng(1); Li, Zhanao(1); Wen, Xingyue(1); Yuan, Libo(1,3); Li, Kang(4); Bowkett, Mark(4); Copner, Nigel(4); Wang, Xiaozhang(5)Source: Sensors and Actuators, B: Chemical Volume: 332 Issue: DOI: 10.1016/j.snb.2021.129517 Published: April 1, 2021Abstract:In this paper, a novel type of in-fiber optofluidic Raman self-assembly graphene oxide (GO)/PDDA/Ag NPs SERS sensor for the adenine in DNA is proposed. The microstructured hollow fiber (MHF) has a channel and a suspended core in microscale, which allows the sample to flow into the fiber. Meanwhile, the GO/PDDA/Ag NPs SERS substrates are modified on the MHF core by chemical bond. When the sample is interacted with the evanescent field excited by the suspended core, the on-line SERS signals can be coupled back to the core and be detected. Here, we carry out on-line optofluidic detection on the adenine samples. The results show that the detection limit (LOD) of the samples of is about 1 × 10?14 M. The unwound DNA solution extracted from biological blood is injected into the MHF. Under the action of the hydrogen bond between PDDA with adenine, the adenine base in DNA is successfully detected and the interference of guanine, cytosine and thymine is eliminated. Significantly, this work provides an integrated self-assembled GO/PDDA/Ag NPs SERS adenine sensor in an optofluidic fiber. This rapid, convenient and sensitive Raman detection sensor of adenine in DNA is expected to have more potential applications in HIV, genetics and other fields. ? 2021 Elsevier B.V.Accession Number: 20210509857634 -
Record 266 of
Title:Influence of Sm3+ doping on the relaxation behaviors of KSr2Nb5O15 ferroelectric ceramics and the luminescence modulation effect by polarization engineering
Author(s):Cao, Shuyao(1); Chen, Qian(1); Li, Yangping(1); Wu, Changying(2); Feng, Xiaoying(1); Xu, Jie(1); Cheng, Guanghua(2,3); Gao, Feng(1)Source: Ceramics International Volume: 47 Issue: 14 DOI: 10.1016/j.ceramint.2021.04.037 Published: July 15, 2021Abstract:The luminescence modulation behavior of lanthanide ion doped materials possesses great potential for applications in sensing, display and anti-counterfeiting devices. Unlike traditional tuning methods for chemical compositions, novel rare-earth doped ferroelectric oxides exhibit attractive luminescence modulation effects via electric polarization engineering, and enrich the development of multifunctional devices. In this work, Sm3+ doped KSr2Nb5O15 ceramics with abundant ferroelectric and luminescent properties were synthesized. The samples show different relaxation behaviors and ferroelectric features upon chemical and structural factors caused by Sm3+ doping, such as average ionic radii, local tolerance factors, and chemical bonds. After polarization at 20 kV/cm for 20 min, a considerable increase (~40%) in the luminescent emission intensity was obtained in 4 mol. % Sm3+ doped KSr2Nb5O15 ceramics. The related luminescence modulation mechanism was attributed to controlling the environmental symmetry around Sm3+ by the electric polarization. ? 2021 Elsevier Ltd and Techna Group S.r.l.Accession Number: 20211710256810 -
Record 267 of
Title:Design of video image acquisition and SDI display in large field of view
Author(s):Zhang, Yongkang(1); Chen, Ping(1); Meng, Xiangsheng(1); Tian, Yan(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 50 Issue: DOI: 10.3788/IRLA20200211 Published: October 25, 2021Abstract:According to the real demand of image real-time storage display and real-time tracking display for large field of view and high-speed camera, which was with Camera Link interface, a large field of view image acquisition and SDI display system based on FPGA was designed. FPGA EP2S90F1020 of Altera Company as the core processor and two pieces of SDRAM MT48LC4M32 were used. A method of image real-time zooming based on FPGA and real-time conversion of Bayer format color image to SDI display was proposed. The real-time display of large field of view color video image, which was Camera Link interface, was realized on SDI video image. The experimental results show that the design method can convert the 2 048×2 048, 100 Hz video image of Camera Link interface into 1 920×1 080, 25 Hz or 1 280×720, 25 Hz, or 720×576, 50 Hz SDI display in real time. In the FPGA environment, the whole image processing time is 8.7 ms, which meets the real-time requirements of the system, and provides an effective implementation method for the real-time display of large field of view video image in embedded system. ? 2021, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved.Accession Number: 20214511111237 -
Record 268 of
Title:808 nm broad-area laser diodes designed for high efficiency at high-temperature operation
Author(s):Lan, Yu(1,2); Yang, Guowen(1,2,3); Liu, Yuxian(1,2); Zhao, Yuliang(1,2); Wang, Zhenfu(1); Li, Te(1); Demir, Abdullah(4)Source: Semiconductor Science and Technology Volume: 36 Issue: 10 DOI: 10.1088/1361-6641/ac2160 Published: October 2021Abstract:Semiconductor lasers with high power conversion efficiency (PCE) and output power are heavily investigated driven by more energy-efficient commercial applications. In this paper, an asymmetric broad area laser (A-BAL) design is studied and compared with a conventional symmetric broad area laser (S-BAL) design for 808 nm single emitter laser diodes. We present a comparative theoretical and experimental investigation by studying the thermal effects on the laser parameters. The output characteristics and efficiency loss paths for the designs were analyzed. The leakage of carriers was identified as the primary source of the PCE reduction with temperature. Suppressing this leakage by optimization of the A-BAL design, a record continuous-wave PCE of 68% at 25 C and 60.4% at 75 C were achieved for a single emitter laser with 10 W output power. These devices deliver high efficiency at high temperatures with reliable operation achieving 2000 h of an accelerated aging lifetime without failures. ? 2021 IOP Publishing Ltd.Accession Number: 20214111013822 -
Record 269 of
Title:Application of machine learning in the alignment of off-Axis optical system
Author(s):Yu, Lei(1); Ma, Caiwen(1); Fu, Xing(1); Yin, Yamei(1); Cao, Mingqiang(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12069 Issue: DOI: 10.1117/12.2606474 Published: 2021Abstract:Coaxial optical system has a symmetry of revolution. Alignment for this kind of optical system is easy. The desired image quality can be rapidly converged. As for off-Axis optical system, traditional optical alignment method can not be used due to the loss of rotational symmetry. Low initial position accuracy makes installation and adjustment more difficult than usual. In this paper, we aim to solve the alignment problem for off-Axis optical system with the help of machine learning and its powerful numerical fitting ability. We carried out our research on alignment method for an Gregorian off-Axis system. The location of primary mirror is fixed as the optical reference. Alignment process is to adjust posture of secondary mirror to acquire ideal image quality. We use Zemax and Python co-simulation technology to get simulated data. Then multi-layer artificial neural network is utilized to fit the mathematical relationship between misalignments and Zernike coefficients. Given the coefficients, the misalignments can be calculated by the neural network. Finally we conduct alignment experiment to verify the proposed method. The result has proved that this method is a fast and efficient alignment solution for the off-Axis optical systems. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Accession Number: 20220211444592 -
Record 270 of
Title:Electromagnetic compatibility design of hyperspectral remote sensing high-speed imaging circuit
Author(s):Liu, Yongzheng(1); Liu, Xuebin(1); Liu, Wenlong(1); Zhang, Xin(1); Chen, Xiaolai(1)Source: Xi Tong Gong Cheng Yu Dian Zi Ji Shu/Systems Engineering and Electronics Volume: 43 Issue: 1 DOI: 10.3969/j.issn.1001-506X.2021.01.04 Published: January 2021Abstract:In the field of hyperspectral remote sensing imaging, the demand of indicators for hyperspectral remote resolution, hyperspectral resolution and large width of imaging loads are improved. To solve the problem that the electromagnetic interference (EMI) of the high-speed electronics of spaceborne hyperspectral imaging is becoming more and more intensive, the target design method to enhance the electromagnetic compatibility (EMC) capability of the spaceborne hyperspectral imager is proposed, and the implementation of the load on a specific series of high resolution hyperspectral imager verified the effectiveness of the targeted design. In order to seek the theoretical methods and technical implementation methods of EMI design for high-speed hyperspectral imagers, the useful explorations is made to provide a useful reference for the design of other spaceborne high-speed imaging loads for remote sensing. ? 2021, Editorial Office of Systems Engineering and Electronics. All right reserved.Accession Number: 20210209767610 -
Record 271 of
Title:Extended focused imaging in microscopy using structure tensor and guided filtering
Author(s):Ren, Zhenbo(1,2); Guan, Peiyan(3); Lam, Edmund Y.(3); Zhao, Jianlin(1)Source: Optics and Lasers in Engineering Volume: 140 Issue: DOI: 10.1016/j.optlaseng.2021.106549 Published: May 2021Abstract:The limited depth-of-field (DOF) in optical microscopic imaging systems prevents them from capturing an entirely focused images when the imaged scene is thick and covers a wide range of depth. Specimens lying outside the DOF is defocused and thus blurred, hindering the subsequent observation and analysis. Extended focused imaging aims at yielding a single all-in-focus image by combining the in-focus information from a stack of partially focused images. In this paper, we present a new algorithm for digitally extending the low DOF of a microscopic imaging system. The method is based on the two-scale decomposition of an image into a base layer and a detail layer, both of which contain information of different scales. Then, with the structure tensor, which is uniquely advantageous for autofocusing multi-focal planes, as the focus measure, initial weight maps are generated. The guided filtering is then employed to optimize the weighted averaging scheme for the fusion of the base and detail layers. We examine the proposed algorithm under incoherent and coherent imaging modalities, i.e., bright-field microscopy and digital holographic microscopy. Qualitative and quantitative comparisons with the existing approaches are carried out using extensive experimental data. The results show the advantages and superior performance of the proposed scheme even in the presence of coherent noise. ? 2021 Elsevier LtdAccession Number: 20210409818635 -
Record 272 of
Title:Research on 3D pose measurement algorithm based on binocular vision
Author(s):Shan, Fu Qiang(1); Wang, Feng(1); Zhang, Hai Feng(1)Source: Journal of Physics: Conference Series Volume: 1792 Issue: 1 DOI: 10.1088/1742-6596/1792/1/012043 Published: February 19, 2021Abstract:Based on binocular vision, this paper proposes an algorithm for fast and accurate three-dimensional measurement. The binocular 3D measurement system is mainly divided into four parts: binocular calibration, binocular correction, binocular matching and pose calculation. In this paper, an international softwareM is used to achieve camera calibration, the FAST algorithm is used to achieve the extraction of feature points, and the matching method that combines gray-level correlation coefficient (cc) and epipolar constraint is selected. Experiments have verified that this algorithm can accurately achieve three-dimensional pose measurement. ? 2021 Journal of Physics: Conference Series.Accession Number: 20211110079184 -
Record 273 of
Title:Polarimetric dehazing utilizing Vis-NIR spectral image fusion
Author(s):Xia, Pu(1); Chen, Xiaolai(1); Gao, Xiaohui(1)Source: Proceedings - 2021 International Conference on Intelligent Computing, Automation and Systems, ICICAS 2021 Volume: Issue: DOI: 10.1109/ICICAS53977.2021.00017 Published: 2021Abstract:Polarimetric dehazing methods have good ability in restoring images contaminated by haze. But noise and color distortion come along with the dehazing process, and those methods lack the ability to recover targets of long-distance. Our previous study has shown that the penetration ability of light is related with wavelength, light of long wavelength, especially in the infrared band, receives less attenuation from haze. Based on that fact, we decompose the dehazing process into 16 different spectral bands to achieve the optimized dehazing performance. An infrared band is added to enhance the dehazing performance in short-wavelength channels, thus increases the range of visibility and corrects the color distortion. The dehazed image is reconstructed through image fusion of the dehazed bands. Experimental analyses reveal enhanced details and reduced noise of dehazed images. Particularly, our method works well in retaining the color information of haze contaminated images. The amount of blueshift can be reduced by 71% at least. ? 2021 IEEE.Accession Number: 20221311871478 -
Record 274 of
Title:High-power operation and lateral divergence angle reduction of broad-area laser diodes at 976 nm
Author(s):Liu, Yuxian(1,2); Yang, Guowen(1,2,3); Wang, Zhenfu(1); Li, Te(1); Tang, Song(3); Zhao, Yuliang(1,2); Lan, Yu(1,2); Demir, Abdullah(4)Source: Optics and Laser Technology Volume: 141 Issue: DOI: 10.1016/j.optlastec.2021.107145 Published: September 2021Abstract:Broad-area diode lasers with high output power and low lateral divergence angle are highly desired for extensive scientific and industrial applications. Here, we report on the epitaxial design for higher output power and a flared waveguide design for reduced divergence, which leads to high power operation with a low lateral divergence angle. A vertically asymmetric epitaxial structure was employed and optimized for low internal optical loss and high efficiency to realize high output power operation. Using a flared waveguide design, the lateral divergence angle was efficiently reduced by decreasing the number of high-order lateral optical modes significantly. The flared waveguide design introduces a smooth modification of the ridge width along the cavity without deteriorating laser performance. Based on the optimized epitaxial and waveguide design, we scaled the waveguide width to realize high continuous-wave power of 34.5 W at 25 °C. A low lateral divergence angle of 8° and high power conversion efficiency of 60% were achieved at the operating power level of 25 W. The life test data (30 A at 45 °C for 39 units, 0 failures in 1000 h) demonstrated reliable operation illustrating the efficient design for reduced lateral divergence angle and high operating power. ? 2021 Elsevier LtdAccession Number: 20211810277558 -
Record 275 of
Title:Unsupervised Feature Selection using Pseudo Label Approximation
Author(s):Deng, Ren(1); Liu, Ye(1); Luo, Liyan(1); Chen, DongJing(1); Li, Xijie(2)Source: ACM International Conference Proceeding Series Volume: Issue: DOI: 10.1145/3457682.3457758 Published: February 26, 2021Abstract:Feature selection is a machine learning technique that selects a representative subset of all features available in order to reduce the time and space needed to process high-dimensional data. Traditional feature selection methods include filter, wrapper, and embedded approaches. However, many conventional methods' performances are not suitable in many contexts. This paper proposes a new unsupervised feature selection model based on pseudo label approximation. The new derived model incorporates a projection error, a sparsity regularization, and a manifold regularization term that preserves the manifold structure of the original data. Finally, implementation of the new model onto five distinct datasets validates the effectiveness of the proposed model. ? 2021 ACM.Accession Number: 20212810613327 -
Record 276 of
Title:Research on precision measurement and assembly technology of fery prism
Author(s):Fu, Xihong(1,2); Li, Libo(1,2); Ma, Nana(1); Chou, Xiaoquan(1); Kang, Shifa(1); Li, Hua(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11763 Issue: DOI: 10.1117/12.2584980 Published: 2021Abstract:From the special structure, processing technology and function of Fery prism in spectral imager, and the structural design features of a certain research spectral imager project, an assembly measurement method based on CMM, PSM and high precision rotating device is proposed, which combines the principles of space measurement, point source collimation and 3D mathematical modeling, the on-line inspection and alignment technology of Fery prism assembly are studied. Firstly, the key parameters of a single curved prism, such as curvature radius of surface, spherical coordinates, deflection angle of optical axis and off-axis are measured by CMM. Secondly, the Fery prism assembly is assembled by CMM, PSM and high precision rotating device. The space coordinates between the components are measured by CMM, and the position of the Spherical Center and the deflection angle are precisely determined by point source microscope. Finally, the actual assembly effect of the Fery Prism Assembly is reappeared through the data processing of the computer software, and the directional offset between the Fery prism assembly and the theoretical model is given, the precision assembly of Fery prism aseembly is completed by azimuth rotation and trimming mat processing. It provides a new technology method for on-line precision assembly of Fery prism module in Spectral Imager, which has strong operability and high measurement precision, and is suitable for precision detection and assembly of Fery prism module of different sizes. ? 2021 SPIEAccession Number: 20211410162270