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Reduction of the resolution Losses in Dual-Wavelength Storage

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Chinese Physics Letters 2000年第9期17卷 663-665页

作者：张心正许京军孙骞 Nouel Y.Kamber 刘思敏李飞飞黄辉张光寅 Photonics Research Center College of Physical ScienceNankai UniversityTianjin 300071

The dual-wavelength storage for multi-page storage with the nondestructive readout is investigated in the double doped lithium niobate *** image field losses are minimized by adjusting the readout wave vectors,and the... 详细信息

关键词： lithium vectors resolution

Super-resolution Imaging by using a Metallic Rod Array in the Near Infrared Region

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Chinese Physics Letters 2012年第4期29卷 210-212页

作者：姚洁叶永红 College of Physics Science and Technology Nanjing Normal UniversityNanjing 210046

An array of metallic rods can transport details below the diffraction limit of an object from the front face to the back *** super-resolution imaging system has been studied in the microwave,mid-infrared and optical *** investigate its performance in the near infrared (1550nm) *** simulations show that the near-field components of dipole sources are transferred by the excitation and propagation of the surface plasmon mode of the *** appropriate length of rods is determined by the excited surface plasmon *** spatial resolution is greatly affected by the loss of metal.

关键词： resolution Infrared details

Effects of raster resolution on landslide susceptibility mapping:A case study of Shenzhen

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Science China(Technological Sciences) 2008年第S2期51卷 188-198页

作者： TIAN Yuan,XIAO ChenChao,LIU Yu & WU Lun Institute of RS and GIS,Peking University,Beijing 100871,China Institute of RS and GIS Peking University Beijing China

resolution has been playing a significant role in landslide susceptibility mapping and hazard *** on geographical information system(GIS) and information model,the effects of raster resolution on landslide susceptibility mapping are studied in a central area of Shenzhen,*** factors are selected to calculate landslide susceptibility with eleven groups of different resolutions(5 to 190 m).It has been found that a finer resolution does not necessarily lead to a higher accuracy of landslide susceptibility mappings,while the result of 90 m-resolution has the best accuracy and the 150 m-resolution has the worst *** accuracy curve is in a shape of "W" along with resolution decreasing:1) The accuracy decreases from 5 to 70 m;2) and then the best accuracy appears at 90 m,which is almost the same as the mean size of landslides in study area;3) the accuracy decreases again from 110 to 150 m;4) and finally the accuracy increases from 150 to 190 *** sensitivity analysis indicates that the effects of raster resolution are mainly caused by the resolution impact on landform parameter derivation,while factors like geology and human activity are very insensitive to resolutions.A further study shows that in flat,ridge,and slope foot terrains,the susceptibility mapping result is sensitive to resolution,but in the sloping surface area the sensitivity is much less sensitive to *** last,by choosing study areas with different sizes,it has also been found that the optimal resolutions are variable due to size of study *** the study area is larger than a threshold,which is 135 km2 in this study,and the optimal resolution is almost fixed.

关键词： resolution sensitivity landslide susceptibility mapping digital elevation model(DEM) information model

Simulation study of energy resolution with changing pixel size for radon monitor based on Topmetal-Ⅱ^- TPC

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Nuclear Science and Techniques 2019年第1期30卷 49-57页

作者： Meng-Yao Huang Hua Pei Xiang-Ming Sun Shu-Guang Zou Department of Physics and Astronomy Iowa State University PLAC Key Laboratory of Quark & Lepton Physics (MOE)Central China Normal University College of Information Science and Engineering Henan University of Technology

In this paper, we study how pixel size influences energy resolution for a proposed pixelated detector—a high sensitivity, low cost, and real-time radon monitor based on a Topmetal-Ⅱ^- time projection chamber(TPC). This monitor was designed to improve spatial resolution for detecting radon alpha particles using Topmetal-Ⅱ^- sensors assembled by a 0.35 lm CMOS integrated circuit *** to concerns that small pixel size might have the side effect of worsening energy resolution due to lower signalto-noise ratio, a Geant4-based simulation was used to investigate the dependence of energy resolution on pixel sizes ranging from 60 to 600 lm. A non-monotonic trend in this region shows the combined effect of pixel size and threshold on pixels, analyzed by introducing an empirical expression. Pixel noise contributes 50 keV full-width at half-maximum energy resolution for 400 lm pixel size at 1–4σ threshold that is comparable to the energy resolution caused by energy fluctuations in the TPC ionization process( ~20 keV). The total energy resolution after combining both factors is estimated to be 54 keV for a pixel size of 400 lm at 1–4σ threshold. The analysis presented in this paper would help choosing suitable pixel size for future pixelated detectors.

关键词： Geant4 Energy resolution Pixel size Radon monitor Topmetal

Novel high-resolution DOA estimation using subspace projection method

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 110-116页

作者： SI Wei-jian LAN Xiao-yu ZOU Yan College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China No. 91404 Army Qinhuangdao 066000 China

The performance of multiple signal classification （MUSIC） algorithm with regard to solving closely spaced direction of arrivals （DOAs） depends strongly upon the signal-to-noise ratio （SNR） and snapshots. In order to solve this problem, a method by reconstructing the spatial spectrum function with both noise subspace and signal subspace is presented in this paper. The key idea is to apply the full information contained in covariance matrix and change the projection weights of steering vector on the noise and signal subspace by their revised eigenvalues, respectively. Comparing with the MUSIC algorithm, it does not increase any computational complexity either, and remarkably, it has the advantages of simultaneously reducing noise and keeping the high-resolution ability under low SNR and small sample sized scenarios. Simulation and experiment results are included to demonstrate the superior performance of the proposed algorithm.

关键词： direction &arrival (DOA) multiple signal classification low SNR resolution subspace projection

Ultra-resolution scalable microprinting

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微系统与纳米工程(英文) 2023年第3期9卷 195-207页

作者： Callum Vidler Kenneth Crozier David Collins Department of Biomedical Engineering University of MelbourneMelbourneVICAustralia School of Physics University of MelbourneVictoria 3010Australia Department of Electrical and Electronic Engineering University of MelbourneVictoria 3010Australia Australian Research Council(ARC)Centre of Excellence for Transformative Meta-Optical Systems University of MelbourneVictoria 3010Australia The Graeme Clark Institute The University of MelbourneParkville 3052 VICAustralia

Projection micro stereolithography(PµSL)is a digital light processing(DLP)based printing technique for producing structured *** this approach there is often a tradeoff between the largest object that can be printed and the minimum feature size,with higher resolution generally reducing the overall extent of the *** ability to produce structures with high spatial resolution and large overall volume,however,is immensely important for the creation of hierarchical materials,microfluidic devices and bioinspired *** this work,we report a low-cost system with 1µm optical resolution,representing the highest resolution system yet developed for the creation of micro-structured parts whose overall dimensions are nevertheless on the order of *** do so,we examine the limits at which PµSL can be applied at scale as a function of energy dosage,resin composition,cure depth and in-plane feature *** doing so we develop a unique exposure composition approach that allows us to greatly improve the resolution of printed *** ability to construct high-resolution scalable microstructures has the potential to accelerate advances in emerging areas,including 3D metamaterials,tissue engineering and bioinspired constructs.

关键词： lithography resolution printing

resolution and contrast enhancement in optical subtraction microscopy with annular aperture

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Optoelectronics Letters 2019年第2期15卷 93-97页

作者：李正亚王湘晖范飞程洁嵘常胜江 Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Institute of Modern Optics Nankai University

A method for improving lateral resolution and reducing imaging distortion of optical subtraction microscopy is ***, an azimuthally polarized(AP) light is modulated by an annular ***, an image with higher lateral resolution is obtained by subtracting an image obtained by an annular AP beam from an image obtained by a radially polarized *** simulation results demonstrate that compared with the case without the annular aperture, negative side-lobes in the effective point spread function are effectively suppressed, and the imaging quality of subtraction microscopy is obviously enhanced.

关键词： PSF resolution enhancement subtraction

Dual-tree complex wavelet transform and super-resolution based video inpainting application to object removal and error concealment

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CAAI Transactions on Intelligence Technology 2020年第4期5卷 314-319页

作者： Gajanan Tudavekar Sanjay R.Patil Santosh S.Saraf Department of Electronics&Communication Engineering Angadi Institute of Technology and ManagementBelagaviKarnatakaIndia Visvesvaraya Technological University BelagaviKarnatakaIndia Department of Electronics&Telecommunication Engineering Marathwada Institute of TechnologyAurangabadMaharashtraIndia Department of Electronics&Communication Engineering KLS Gogte Institute of TechnologyBelagaviKarnatakaIndia

Video inpainting is a technique that fills in the missing regions or gaps in a video by using its known *** existing video inpainting algorithms are computationally expensive and introduce seam in the target region that arises due to variation in brightness or contrast of the *** overcome these drawbacks,the authors propose a novel two-stage *** the first step,sub-bands of wavelets of a low-resolution image are obtained using the dualtree complex wavelet *** algorithm and auto-regression technique are then applied to these subbands to inpaint the missing *** fuzzy logic-based histogram equalisation is used to further enhance the image by preserving the image brightness and improve the local *** the second step,the image is enhanced using super-resolution *** process of down-sampling,inpainting and subsequently enhancing the video using the super-resolution technique reduces the video inpainting *** framework is tested on video sequences by comparing and analysing the structural similarity index matrix,peak-signal-to-noise ratio,visual information fidelity in pixel domain and execution time with the state-of-the-art *** experimental analysis gives visually pleasing results for object removal and error concealment.

关键词： resolution video image

Spectral methods for spatial resolution improvement of digital images

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Science China(Technological Sciences) 1999年第4期42卷 365-375页

作者：郝鹏威徐冠华朱重光 Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China

A general matrix formula is proposed for signal spectral aliasing of various or mutual resolution, the concept of spectral aliasing matrix is introduced, and some general spectral methods for spatial resolution improvement from multiframes of undersampled digital images are discussed. A simplified iterative method of parallel row-action projection for spectral de-aliasing is also given. The method can be applied to multiframe images with various spatial resolution,relative displacement, dissimilar point spread function, different image radiance, and additive random noise. Some experiments with a resolution test pattern and an image of vertical fin performed the convergence and the effectiveness of the algorithms.

关键词： spectral aliasing spectral de-aliasing spectral aliasing matrix (SAM) spatial resolution spatial resolution improvement.