2019
2019
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Record 169 of
Title:Face Sketch Synthesis by Multidomain Adversarial Learning
Author(s):Zhang, Shengchuan(1); Ji, Rongrong(1); Hu, Jie(1); Lu, Xiaoqiang(2); Li, Xuelong(3)Source: IEEE Transactions on Neural Networks and Learning Systems Volume: 30 Issue: 5 DOI: 10.1109/TNNLS.2018.2869574 Published: May 2019Abstract:Given a training set of face photo-sketch pairs, face sketch synthesis targets at learning a mapping from the photo domain to the sketch domain. Despite the exciting progresses made in the literature, it retains as an open problem to synthesize high-quality sketches against blurs and deformations. Recent advances in generative adversarial training provide a new insight into face sketch synthesis, from which perspective the existing synthesis pipelines can be fundamentally revisited. In this paper, we present a novel face sketch synthesis method by multidomain adversarial learning (termed MDAL), which overcomes the defects of blurs and deformations toward high-quality synthesis. The principle of our scheme relies on the concept of 'interpretation through synthesis.' In particular, we first interpret face photographs in the photodomain and face sketches in the sketch domain by reconstructing themselves respectively via adversarial learning. We define the intermediate products in the reconstruction process as latent variables, which form a latent domain. Second, via adversarial learning, we make the distributions of latent variables being indistinguishable between the reconstruction process of the face photograph and that of the face sketch. Finally, given an input face photograph, the latent variable obtained by reconstructing this face photograph is applied for synthesizing the corresponding sketch. Quantitative comparisons to the state-of-the-art methods demonstrate the superiority of the proposed MDAL method. ? 2012 IEEE.Accession Number: 20184105916868 -
Record 170 of
Title:Impact of various parameters on nanostructures fabrication mechanism on silicon surface with AFM tip induced local anodic oxidation
Author(s):Wang, Xuewen(1,2,3); Theogene, Barayavuga(1,2); Mei, Huanhuan(4); Zhang, Jianwei(1,2); Huang, Chenchen(1,2); Ren, Xiaoying(1,2); Xu, Muxun(1)Source: Ferroelectrics Volume: 549 Issue: 1 DOI: 10.1080/00150193.2019.1592545 Published: September 10, 2019Abstract:The AFM tip induced local anodic oxidation (LAO) nanolithography is capable of manufacturing nanometer scale structures and devices for future generation. Experimental studies of LAO on silicon surface, implemented in atmospheric environment by AFM, are presented in this paper. A series of nanostructures with complex patterns was fabricated and analyzed by AFM. The results indicated that various of parameters, such as the applied voltage, pulse time, and ambient humidity, have a strong impact on the height of the nanostructures generated in this way. An advantage of the presented approach is to be utilized in future processing steps in the same environment. ? 2019, ? 2019 Taylor & Francis Group, LLC.Accession Number: 20194407602096 -
Record 171 of
Title:Principle component analysis and random forest based all-fiber activity monitoring
Author(s):Han, Shuying(1,4); Xu, Wei(2,3); You, Shanhong(1); Dong, Bo(2,3); Yu, Changyuan(5); Zhao, Wei(2,3)Source: Optics InfoBase Conference Papers Volume: Part F138-ACPC 2019 Issue: DOI: null Published: 2019Abstract:An activity monitoring algorithm based on principle component analysis and random forest is proposed, identifying three kinds of activities obtained from Mach-Zehnder interferometer with accuracy of 99.5% within one second, namely, normal, nobody and movement. Asia Communications and Photonics Conference (ACP) ? OSA 2019 ? 2019 The Author(s)Accession Number: 20202008653105 -
Record 172 of
Title:GETNET: A General End-To-End 2-D CNN Framework for Hyperspectral Image Change Detection
Author(s):Wang, Qi(1); Yuan, Zhenghang(1); Du, Qian(2); Li, Xuelong(3,4)Source: IEEE Transactions on Geoscience and Remote Sensing Volume: 57 Issue: 1 DOI: 10.1109/TGRS.2018.2849692 Published: January 2019Abstract:Change detection (CD) is an important application of remote sensing, which provides timely change information about large-scale Earth surface. With the emergence of hyperspectral imagery, CD technology has been greatly promoted, as hyperspectral data with high spectral resolution are capable of detecting finer changes than using the traditional multispectral imagery. Nevertheless, the high dimension of the hyperspectral data makes it difficult to implement traditional CD algorithms. Besides, endmember abundance information at subpixel level is often not fully utilized. In order to better handle high-dimension problem and explore abundance information, this paper presents a general end-To-end 2-D convolutional neural network (CNN) framework for hyperspectral image CD (HSI-CD). The main contributions of this paper are threefold: 1) mixed-Affinity matrix that integrates subpixel representation is introduced to mine more cross-channel gradient features and fuse multisource information; 2) 2-D CNN is designed to learn the discriminative features effectively from the multisource data at a higher level and enhance the generalization ability of the proposed CD algorithm; and 3) the new HSI-CD data set is designed for objective comparison of different methods. Experimental results on real hyperspectral data sets demonstrate that the proposed method outperforms most of the state of the arts. ? 1980-2012 IEEE.Accession Number: 20183105632461 -
Record 173 of
Title:Ridge waveguides in magneto-optical glasses formed by combination of proton implantation and precise diamond blade dicing
Author(s):Zhu, Qi-Feng(1); Long, Xue-Wen(2); Wang, Yue(1); Shen, Xiao-Liang(1); Guo, Hai-Tao(3); Fu, Li-Li(1); Liu, Chun-Xiao(1)Source: Optical Engineering Volume: 58 Issue: 5 DOI: 10.1117/1.OE.58.5.057107 Published: May 1, 2019Abstract:We report on the fabrication of a ridge waveguide in the Tb3 +-doped aluminum borosilicate glass by combining the 550-keV proton implantation and the precise diamond blade dicing with a rotating speed of 20,000 rpm. The relative atom displacement of the original structure induced by the proton implantation is simulated by Stopping and Range of Ions in Matter 2013 in the Tb3 +-doped aluminum borosilicate glass. The morphology of the ridge waveguide is acquired by scanning electron microscopy. The near-field intensity distribution of the waveguide is recorded by the end-face coupling system, which indicates that the light can be well confined in the ridge waveguide region. ? 2019 Society of Photo-Optical Instrumentation Engineers (SPIE).Accession Number: 20193007230982 -
Record 174 of
Title:Simulation of InP/In0.53Ga0.47As/InP infrared photocathode with high quantum yield
Author(s):Zhou, Zhenhui(1,2,3); Xu, Xiangyan(1,3); Liu, Hulin(1,3); Li, Yan(4); Lu, Yu(1,3); Qian, Sen(5,6); Wei, Yonglin(1,3); He, Kai(1,3); Sai, Xiaofeng(1,3); Tian, Jinshou(1,3); Chen, Ping(1,3)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 48 Issue: 2 DOI: 10.3788/IRLA201948.0221002 Published: February 25, 2019Abstract:An InP/In0.53Ga0.47As/InP infrared photocathode model was established. The In0.53Ga0.47As absorber layer was designed as a multi-layer structure, the impurities of it were exponentially distributed by doping with different concentrations of the thin layers. The one-dimensional continuity equations and boundary conditions of the photoelectron in the absorber layer and the emissive layer were given and the probability that photoelectrons overcome the launch of the active layer barrier into the vacuum was calculated. The effects of absorber layer thickness, doping concentration and cathode bias voltage on the internal quantum efficiency of the cathode was simulated under the condition of picosecond response time, and then the law of the external quantum yield of the cathode was obtained with the above three factors. The results show that, when the doping concentration of the absorber layer changes within the range of 1015-1018 cm-3, The internal quantum efficiency change is very small; as the thickness of the absorber layer increases within 0.09-0.81 μm, the internal quantum efficiency increases. As the external bias voltage increases, the internal quantum efficiency increases first and then tends to be stable. A set of cathode design parameters that could achieve both high quantum efficiency and fast time response were presented. Theoretically, an external quantum yield of 8.4% can be obtained for 1.55 μm incident light, and the response time is 49 ps. ? 2019, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved.Accession Number: 20191506748535 -
Record 175 of
Title:Indoor PM2.5 Profiling with a Novel Side-Scatter Indoor Lidar
Author(s):Qiu, Youwei(1); Tao, Shu(1,3); Yun, Xiao(1); Du, Wei(1); Shen, Guofeng(1); Lu, Cengxi(1); Yu, Xinyuan(1); Cheng, Hefa(1); Ma, Jianmin(1); Xue, Bin(2); Tao, Jinyou(2); Dai, Junhu(3); Ge, Quansheng(3)Source: Environmental Science and Technology Letters Volume: 6 Issue: 10 DOI: 10.1021/acs.estlett.9b00544 Published: October 8, 2019Abstract:Indoor air pollution dominates respiration exposure because people spend most of their time indoors. Generally, indoor PM2.5 concentrations are monitored at a fixed height in the breathing zone. However, the concentrations of PM2.5 likely vary vertically; thus, the vertical concentration profiles would help improve the understanding of indoor air pollution. Based on the basic principle of bistatic Lidar for boundary aerosol profiling, an indoor Lidar (I-Lidar) was developed to profile the vertical distribution of PM2.5 by imaging the PM2.5 scattering of a vertical laser beam onto a complementary metal oxide semiconductor (CMOS) camera. Unlike bistatic Lidar, the I-Lidar views the vertical laser beam perpendicularly from the side, which enables a high and relatively uniform vertical resolution throughout the profile. The images collected by I-Lidar were adjusted for transmission and scattering attenuation and calibrated against the measured PM2.5 concentrations using an array of PM2.5 sensors. The new device was tested in the field, and the measurements in a living room and kitchen of a rural household revealed the existence of vertical trends and dynamic change of PM2.5 concentrations. Potential applications of the device are discussed. ? 2019 American Chemical Society.Accession Number: 20194207539539 -
Record 176 of
Title:Study on the tail in TDOE of the coated MCP-PMT and its suppression
Author(s):Chen, Lin(1); Wang, Xingchao(2,3); Tian, Jinshou(4); Fan, Lixing(1); Tian, Liping(1); Shen, Lingbin(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11184 Issue: DOI: 10.1117/12.2537851 Published: 2019Abstract:Depositing a high secondary electron yield (SEY) film on the microchannel plate (MCP) input electrode is supposed to be an effective approach to improve the photoelectron collection efficiency (CE) of photomultiplier tubes based on MCPs (MCP-PMTs). Nevertheless, secondaries promoted by the photoelectrons striking the MCP input face may cause a long tail in the time distribution of the output electrons (TDOE). In our work, laying a conductive grid upon the MCPs is proposed as an effective approach to suppress the tail. A three-dimensional MCP-PMT model is developed in CST STUDIO SUITE to systematically investigate the dependence of the TDOE on the applied voltage (U) of the grid at the coated material SEY=6. Simulation results show that high voltage applied on the grid could suppress the delay pulse effectively. The optimal U is above 500 V. ? 2019 SPIE.Accession Number: 20200308041897 -
Record 177 of
Title:Ultrabroadband mid-infrared emission from Cr2+-doped infrared transparent chalcogenide glass ceramics embedded with thermally grown ZnS nanorods
Author(s):Lu, Xiaosong(1); Lai, Zhiqiang(1); Zhang, Runan(1); Guo, Haitao(2); Ren, Jing(1); Strizik, Lukas(3); Wagner, Tomas(3,4); Farrell, Gerald(5); Wang, Pengfei(1,6)Source: Journal of the European Ceramic Society Volume: 39 Issue: 11 DOI: 10.1016/j.jeurceramsoc.2019.04.048 Published: September 2019Abstract:We report, for the first time to our knowledge, an ultrabroadband mid-infrared (MIR)emission in the range of 1800–2800 nm at room temperature from a Cr2+-doped chalcogenide glass ceramic embedded with pure hexagonal (wurtzite)β-ZnS nanorods and study the emission-dependent properties on the doping concentration of Cr2+. A new family of chalcogenide glasses based on (100 ? x)Ge1.5As2S6.5 – x ZnSe (in mol.%)was prepared by melt-quenching method. The Cr2+: β-ZnS nanorods of ?150 nm in diameter and ?1 μm in length were grown in the Cr2+-doped glass after thermal annealing. The compositional variations of glass structures and optical properties were studied. The crystalline phase, morphology of the thermally grown nanorods, and the microscopic elemental distributions were characterized using advanced nanoscale transmission electron microscopy analyses. ? 2019 Elsevier LtdAccession Number: 20191906869658 -
Record 178 of
Title:Photorefractive effect of low-temperature-grown aluminum gallium arsenide
Author(s):Zhong, Zi-Yuan(1,2); He, Kai(1); Yuan, Yun(3); Wang, Tao(1); Gao, Gui-Long(1); Yan, Xin(1); Li, Shao-Hui(1); Yin, Fei(1); Tian, Jin-Shou(1,4)Source: Wuli Xuebao/Acta Physica Sinica Volume: 68 Issue: 16 DOI: 10.7498/aps.68.20190459 Published: August 20, 2019Abstract:The ternary compound aluminum gallium arsenide is an important material that can be used in all-optical solid-state ultrafast diagnostic technology. The low-temperature-epitaxially-grown AlGaAs (LT-AlGaAs) not only has the characteristics of ultra-short carrier lifetime of low-temperature-grown gallium arsenide (LT-GaAs), but also possesses the advantage of adjustability of band gap, which will provide great flexibility for the design of ultra-fast diagnostic systems. We use low-temperature epitaxial growth technology to grow AlGaAs on a GaAs substrate. The low-temperature-grown AlGaAs can effectively absorb 400 nm pump light to generate excess carrier. Therefore, we use a femtosecond laser with a wavelength of 800 nm and a pulse width of 200 fs as a light source to generate 400-nm pump light after passing through the BBO crystal, and 800 nm light without frequency doubling as the probe light. Using such a light source, we build a pump probe experimental platform to test the LT-AlGaAs. We normalize the experimental results and deconvolute it with the normalized laser pulses to obtain the response function of the semiconductor to the pump light. Therefore, we know that the nonequilibrium carrier relaxation time is less than 300 fs, and the nonequilibrium carrier recombination time is 2.08 ps. Due to the special passivation process, the effect of surface recombination on the carrier decay process is greatly reduced. The As clusters introduced by low-temperature epitaxial growth form deep level defects are the main factor for accelerating carrier recombination. In order to understand the complex process of photogenerated nonequilibrium carriers in depth, we use the indirect recombination theory of single recombination center to calculate the carrier recombination process, and establish an LT-AlGaAs carrier evolution model. Thus we obtain the key physical parameter related to the recombination rate, which is the carrier trapping area. We also use a theoretical model of carrier-regulated refractive index to calculate the effect of carrier concentration on the amount of change in refractive index. Combining our AlGaAs carrier evolution model, we simulate the refractive index change process of LT-AlGaAs after being illuminated by pump light. The simulation results are in good agreement with the experimental results. The method can be used for the quantitative analysis of carrier evolution characteristics of semiconductor materials, and it can conduce to the optimization and improvement of ultra-fast response semiconductor materials. ? 2019 Chinese Physical Society.Accession Number: 20194207561283 -
Record 179 of
Title:Wind uncertainty analysis of onboard interferometer based on O3 radiation source
Author(s):He, Weiwei(1); Wu, Kuijun(2); Feng, Yutao(3); Wang, Houmao(4); Fu, Di(3); Liu, Qiuxin(1); Yan, Xiaohu(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 48 Issue: 8 DOI: 10.3788/IRLA201948.0813001 Published: August 25, 2019Abstract:The onboard airglow imaging interferometer can obtain the spatial distribution and temporal evolution information of the global atmospheric wind by using the limb-viewing mode, which makes it a research hotspot in the field of international satellite remote sensing. The O3 radiation source based Michelson onboard imaging interferometer can detect the atmospheric wind field in the stratosphere region through all-day. But there is more complex wind uncertainty because of working in the infrared band. Therefore, on the basis of limb-viewing forward simulation, the instrumental thermal background signal was studied, the measurement noise was analyzed, the atmospheric wind error caused by the measurement noise of atmospheric signal and the instrument thermal background noise was given, and error profile of line-of-sight wind was obtained by apparent quantities simulation and signal-to-noise ratio analysis. The uncertainty analysis shows that the O3 radiation source based Michelson imaging interferometer can detect atmospheric wind in the range of 15-45 km onboard through all-day, and the inversion accuracy is better than 1 -2 m/s. This research provides important theoretical guidance for atmospheric wind measurement based on infrared radiation source. At the same time, it has great engineering significance and practical value for the development of infrared Michelson imaging interferometer. ? 2019, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved.Accession Number: 20194207544451 -
Record 180 of
Title:Convolutional Edge Constraint-Based U-Net for Salient Object Detection
Author(s):Han, Le(1,2); Li, Xuelong(3); Dong, Yongsheng(1,4)Source: IEEE Access Volume: 7 Issue: DOI: 10.1109/ACCESS.2019.2910572 Published: 2019Abstract:The salient object detection is receiving more and more attention from researchers. An accurate saliency map will be useful for subsequent tasks. However, in most saliency maps predicted by existing models, the objects regions are very blurred and the edges of objects are irregular. The reason is that the hand-crafted features are the main basis for existing traditional methods to predict salient objects, which results in different pixels belonging to the same object often being predicted different saliency scores. Besides, the convolutional neural network (CNN)-based models predict saliency maps at patch scale, which causes the objects edges of the output to be fuzzy. In this paper, we attempt to add an edge convolution constraint to a modified U-Net to predict the saliency map of the image. The network structure we adopt can fuse the features of different layers to reduce the loss of information. Our SalNet predicts the saliency map pixel-by-pixel, rather than at the patch scale as the CNN-based models do. Moreover, in order to better guide the network mining the information of objects edges, we design a new loss function based on image convolution, which adds an L1 constraint to the edge information of saliency map and ground-truth. Finally, experimental results reveal that our SalNet is effective in salient object detection task and is also competitive when compared with 11 state-of-the-art models. ? 2013 IEEE.Accession Number: 20191906880356