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Investigation of hearing aid users'speech understanding in noise and their spectral-temporal resolution skills
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作者 Mert Kılıç Eyyup Kara 《Journal of Otology》 CAS CSCD 2023年第3期146-151,共6页
Purpose:Our study aims to compare speech understanding in noise and spectral-temporal resolution skills with regard to the degree of hearing loss,age,hearing aid use experience and gender of hearing aid users.Methods:... Purpose:Our study aims to compare speech understanding in noise and spectral-temporal resolution skills with regard to the degree of hearing loss,age,hearing aid use experience and gender of hearing aid users.Methods:Our study included sixty-eight hearing aid users aged between 40-70 years,with bilateral mild and moderate symmetrical sensorineural hearing loss.Random gap detection test,Turkish matrix test and spectral-temporally modulated ripple test were implemented on the participants with bilateral hearing aids.The test results acquired were compared statistically according to different variables and the correlations were examined.Results:No statistically significant differences were observed for speech-in-noise recognition,spectraltemporal resolution among older and younger adults in hearing aid users(p>0.05).There wasn’t found a statistically significant difference among test outcomes as regards different hearing loss degrees(p>0.05).Higher performances were obtained in terms of temporal resolution in male participants and participants with more hearing aid use experience(p<0.05).Significant correlations were obtained between the results of speech-in-noise recognition,temporal resolution and spectral resolution tests performed with hearing aids(p<0.05).Conclusion:Our study findings emphasized the importance of regular hearing aid use and it showed that some auditory skills can be improved with hearing aids.Observation of correlations among the speechin-noise recognition,temporal resolution and spectral resolution tests have revealed that these skills should be evaluated as a whole to maximize the patient’s communication abilities. 展开更多
关键词 Hearing aids Speech in noise spectral resolution Speech intelligibility Temporal resolution
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Research and application of spectral inversion technique in frequency domain to improve resolution of converted PS-wave 被引量:3
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作者 Zhang Hua He Zhen-Hua +3 位作者 Li Ya-Lin Li Rui He Guamg-Ming Li Zhong 《Applied Geophysics》 SCIE CSCD 2017年第2期247-257,323,共12页
Multi-wave exploration is an effective means for improving precision in the exploration and development of complex oil and gas reservoirs that are dense and have low permeability. However, convened wave data is charac... Multi-wave exploration is an effective means for improving precision in the exploration and development of complex oil and gas reservoirs that are dense and have low permeability. However, convened wave data is characterized by a low signal-to-noise ratio and low resolution, because the conventional deconvolution technology is easily affected by the frequency range limits, and there is limited scope for improving its resolution. The spectral inversion techniques is used to identify λ/8 thin layers and its breakthrough regarding band range limits has greatly improved the seismic resolution. The difficulty associated with this technology is how to use the stable inversion algorithm to obtain a high-precision reflection coefficient, and then to use this reflection coefficient to reconstruct broadband data for processing. In this paper, we focus on how to improve the vertical resolution of the converted PS-wave for multi-wave data processing. Based on previous research, we propose a least squares inversion algorithm with a total variation constraint, in which we uses the total variance as a priori information to solve under-determined problems, thereby improving the accuracy and stability of the inversion. Here, we simulate the Gaussian fitting amplitude spectrum to obtain broadband wavelet data, which we then process to obtain a higher resolution converted wave. We successfully apply the proposed inversion technology in the processing of high-resolution data from the Penglai region to obtain higher resolution convened wave data, which we then verify in a theoretical test. Improving the resolution of converted PS-wave data will provide more accurate data for subsequent velocity inversion and the extraction of reservoir reflection information. 展开更多
关键词 spectral inversion resolution broadband wavelet thin reservoir
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Effect of spectral resolution on the measurement of monoaromatic hydrocarbons by DOAS 被引量:2
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作者 PENG Fumin XIE Pinhua +4 位作者 ZHANG Yinghua ZHU Yanwu SI Fuqi LIU Wenqing WANG Junde 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第5期632-640,共9页
The excellent response characteristics and detection sensitivity with much lower operational cost and the capability to discriminate between the isomer of some monoaromatic hydrocarbons (MAHCs) make differential opt... The excellent response characteristics and detection sensitivity with much lower operational cost and the capability to discriminate between the isomer of some monoaromatic hydrocarbons (MAHCs) make differential optical absorption spectroscopy (DOAS) a powerful tool to trace concentration variation of MAHCs. But due to the similarity in chemical structure, those MAHCs have the similar overlapped characteristic absorption structures, which make the selection of instrumental parameter critical to the accurate detection of MAHCs. Firstly, the spectral resolution used in DOAS system determines the nonlinear absorption of O2 and the mass dependence of characteristic absorption structure; thereby it determines the effect of elimination error of O2 absorption in the atmospheric spectra for the detection of MAHCs. Secondly, spectral resolution determines the differential absorption characteristics of twelve MAHCs representing major constituents in technical solvents used in the automobile industry and the interference of spectral overlapping. Thirdly, the spectral resolution determines the sensitivity, time resolution and linear range. So the spectral resolution range with the best ratio of signal to noise is used to determine the most suitable spectral resolution range, as well as the spectral resolution range that ensure the characteristic absorption structure of MAHCs and the minimization of O2 absorption interference. Finally, 0.15-0.16 nm (FWHM: full width at half maximum) is assumed to be closest to the optimum spectral resolution and it is confirmed by the results of practical measurement of MAHCs by DOAS. 展开更多
关键词 differential optical absorption spectroscopy (DOAS) monoaromatic hydrocarbons (MAHCs) spectral resolution characteristic absorption structure
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The ‘Two oceans and one sea' extended range numerical prediction system with an ultra-high resolution atmosphere-ocean-land regional coupled model 被引量:2
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作者 Zhang Shao-Qing Yang LIU +4 位作者 Ma Xiao-Hui Wang Hong-Na Zhang Xue-Feng Yu Xiao-Lin Lu Lv 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第4期364-371,共8页
The‘Two Oceans and One Sea’area(West Pacific,Indian Ocean,and South China Sea;15°S–60°N,39°–178°E)is a core strategic area for the‘21st Century Maritime Silk Road’project,as well as national ... The‘Two Oceans and One Sea’area(West Pacific,Indian Ocean,and South China Sea;15°S–60°N,39°–178°E)is a core strategic area for the‘21st Century Maritime Silk Road’project,as well as national defense.With the increasing demand for disaster prevention and mitigation,the importance of 10–30-day extended range prediction,between the conventional short-term(around seven days)and the climate scale(longer than one month),is apparent.However,marine extended range prediction is still a‘blank point’in China,making the early warning of marine disasters almost impossible.Here,the authors introduce a recently launched Chinese national project on a numerical forecasting system for extended range prediction in the‘Two Oceans and One Sea’area based on a regional ultra-high resolution multi-layer coupled model,including the scientific aims,technical scheme,innovation,and expected achievements.The completion of this prediction system is of considerable significance for the economic development and national security of China. 展开更多
关键词 Numerical prediction system ultra-high resolution multi-layer coupled model extended range prediction
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Simultaneous Determination of Ultraviolet Absorbers and Antibacterial Agents in Textiles by Ultra-High Performance Liquid Chromatography/Orbitrap High Resolution Mass Spectrometry 被引量:1
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作者 Chengyun Wang Tangtang Xie +2 位作者 Rong Xu Junfeng Lin Lixia Li 《World Journal of Engineering and Technology》 2017年第1期1-18,共18页
This paper reported a new analytical method for the simultaneous determination of seven benzotriazole ultraviolet absorbers and seven antibacterial agents in textiles. After ultrasonic extraction for the textile sampl... This paper reported a new analytical method for the simultaneous determination of seven benzotriazole ultraviolet absorbers and seven antibacterial agents in textiles. After ultrasonic extraction for the textile samples in methanol, the solutions were analyzed by ultra-high performance liquid chromotagraphy/orbitrap high resolution mass spectrometry (UPLC/Orbitrap HRMS). It showed that a good chromatographic separation for these target compounds was achieved by a Hypersil GOLD column (100 mm × 2.1 mm × 1.9 μm) with a gradient elution of methanol and 0.1% aqueous formic acid solution (containing 0.5 mmol/L ammonium acetate). Triclosan and 4-chloro-3,5-dimethyl phenol (PCMX) were detected by the orbitrap HRMS in an electrospray ionization (ESI) negative mode while the other twelve target compounds were detected by orbitrap HRMS in ESI positive mode. Full scan experiment was performed over the range from m/z 100 to m/z 500. These target compounds were routinely detected with mass accuracy below 2 × 10-6 (2 ppm) at the optimized conditions. The results showed that the limits of detection (LODs) were in the range from 0.1 to 0.3 μg/kg. The blank samples were spiked at three levels and their average recoveries varied from 80.5% to 96.3% while the relative standard deviation (RSD) changed from 3.2% to 9.9%. The present method was also applied for the determination of those ultraviolet absorbers and antibacterial agents in the commercial textiles. 展开更多
关键词 ultra-high Performance Liquid Chromatography/Orbitrap High resolution Mass Spectrometry Benzotriazoleultraviolet ABSORBERS Isothiazolinone Tric-losan 4-Chloro-3 5-Dimethyl Phenol
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Spectral Resolution Effects on the Lineshape of Photoreflectance
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作者 MA Li-Li SHAO Jun +2 位作者 LÜXiang GUO Shao-Ling LU Wei 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第4期205-208,共4页
Spectral resolution effects on the lineshape of photoreflectance(PR)spectroscopy is experimentally investigated.PR measurements are performed on HgCdTe epilayer and InAs/GaAs quantum dot(QD)low-dimensional samples at ... Spectral resolution effects on the lineshape of photoreflectance(PR)spectroscopy is experimentally investigated.PR measurements are performed on HgCdTe epilayer and InAs/GaAs quantum dot(QD)low-dimensional samples at low temperatures in a spectral resolution range from 8 to 0.5meV.The results indicate that the resolution affects not only the identification of narrow PR features,but also the determination of critical-point energies of identified PR features,and a spectral resolution of as high as 0.5meV may be necessary for low-dimensional semiconductors.The spectral resolution is indeed a crucial parameter,for which the step-scan Fourier transform infrared spectrometer-based PR technique is preferable. 展开更多
关键词 reflectance resolution spectral
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Using the Spectral Similarity Ratio and Morphological Operators for the Detection of Building Locations in Very High Spatial Resolution Images 被引量:1
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作者 Katia Stankov Dong-Chen He 《通讯和计算机(中英文版)》 2013年第3期309-324,共16页
关键词 高空间分辨率 数学形态学 图像检测 多光谱 地点 遥感影像 相似比 IKONOS影像
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Analysis of the Spectral Resolution of a TeO2 based Noncollinear Acousto-Optic Tunable Filter
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作者 Chunguang Zhang Hao Wang Yishen Qiu 《Engineering(科研)》 2011年第3期233-235,共3页
The spectral resolution is a main index of evaluating the performance of the designed acousto-optic tunable filter (AOTF). In this letter, an accurate expression of the spectral resolution is presented by considering ... The spectral resolution is a main index of evaluating the performance of the designed acousto-optic tunable filter (AOTF). In this letter, an accurate expression of the spectral resolution is presented by considering both the birefringence and the rotatory property of TeO2 crystal. The deduced expression is significant in improving the accuracy of the design of an AOTF and pushing the development of the high-performance AOTF. 展开更多
关键词 spectral resolution AOTF spectral BANDWIDTH TeO2
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Application of Ultra-High Resolution STXM-NEXAFS and Nano-SIMS on the Mapping of Carbon Related Samples
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作者 LIANG Bi-qing(Institute of Earth Sciences,Academia Sinica,Taipei 11129,Taiwan) 《矿物学报》 CAS CSCD 北大核心 2011年第S1期1010-1010,共1页
Nano-Scale mapping of minerals and organic compounds give unprecedented high resolution information on the origin and nature of substances,and provide new insight on their correlative distribution and interaction,thus... Nano-Scale mapping of minerals and organic compounds give unprecedented high resolution information on the origin and nature of substances,and provide new insight on their correlative distribution and interaction,thus present a powerful tool to study the progressive changes of geological samples,and may even be applied to study extraterrestrial samples in search of life.One example we present here explore the use of elemental microprobe,X-Ray Photon Spectroscopy(XPS),and synchrotron-based Scanning Transmission X-ray Microscopy(STXM) coupled with Near Edge X-ray Absorption Fine Structure(NEXAFS) Spectroscopy to investigate the surface properties and stability of micron-size organic carbonaceous particles from Central Amazon,Brazil,specifically focusing on black carbon in Kaolinitic Oxisol originated from anthropogenic processes,and their interaction with cations. 展开更多
关键词 SIMS Application of ultra-high resolution STXM-NEXAFS and Nano-SIMS on the Mapping of Carbon Related Samples
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RSPSSL:A novel high-fidelity Raman spectral preprocessing scheme to enhance biomedical applications and chemical resolution visualization
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作者 Jiaqi Hu Gina Jinna Chen +18 位作者 Chenlong Xue Pei Liang Yanqun Xiang Chuanlun Zhang Xiaokeng Chi Guoying Liu Yanfang Ye Dongyu Cui De Zhang Xiaojun yu Hong Dang Wen Zhang Junfan Chen Quan Tang Penglai Guo Ho-Pui Ho Yuchao Li Longqing Cong Perry Ping Shum 《Light(Science & Applications)》 SCIE EI CSCD 2024年第2期366-386,共21页
Raman spectroscopy has tremendous potential for material analysis with its molecular fingerprinting capability in many branches of science and technology.It is also an emerging omics technique for metabolic profiling ... Raman spectroscopy has tremendous potential for material analysis with its molecular fingerprinting capability in many branches of science and technology.It is also an emerging omics technique for metabolic profiling to shape precision medicine.However,precisely attributing vibration peaks coupled with specific environmental,instrumental,and specimen noise is problematic.Intelligent Raman spectral preprocessing to remove statistical bias noise and sample-related errors should provide a powerful tool for valuable information extraction.Here,we propose a novel Raman spectral preprocessing scheme based on self-supervised learning(RSPSSL)with high capacity and spectral fidelity.It can preprocess arbitrary Raman spectra without further training at a speed of~1900 spectra per second without human interference.The experimental data preprocessing trial demonstrated its excellent capacity and signal fidelity with an 88%reduction in root mean square error and a 60%reduction in infinite norm(L__(∞))compared to established techniques.With this advantage,it remarkably enhanced various biomedical applications with a 400%accuracy elevation(ΔAUC)in cancer diagnosis,an average 38%(few-shot)and 242%accuracy improvement in paraquat concentration prediction,and unsealed the chemical resolution of biomedical hyperspectral images,especially in the spectral fingerprint region.It precisely preprocessed various Raman spectra from different spectroscopy devices,laboratories,and diverse applications.This scheme will enable biomedical mechanism screening with the label-free volumetric molecular imaging tool on organism and disease metabolomics profiling with a scenario of high throughput,cross-device,various analyte complexity,and diverse applications. 展开更多
关键词 spectral SCHEME resolution
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Hyper spectral resolution stimulated Raman spectroscopy with amplified fs pulse bursts
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作者 Hongtao Hu Tobias Flöry +5 位作者 Vinzenz Stummer Audrius Pugzlys Markus Zeiler Xinhua Xie Aleksei Zheltikov Andrius Baltuška 《Light(Science & Applications)》 SCIE EI CSCD 2024年第3期566-576,共11页
We present a novel approach for Stimulated Raman Scattering(SRS)spectroscopy in which a hyper spectral resolution and high-speed spectral acquisition are achieved by employing amplified offset-phase controlled fs-puls... We present a novel approach for Stimulated Raman Scattering(SRS)spectroscopy in which a hyper spectral resolution and high-speed spectral acquisition are achieved by employing amplified offset-phase controlled fs-pulse bursts.We investigate the method by solving the coupled non-linear Schrödinger equations and validate it by numerically characterizing SRS in molecular nitrogen as a model compound.The spectral resolution of the method is found to be determined by the inverse product of the number of pulses in the burst and the intraburst pulse separation.The SRS spectrum is obtained through a motion-free scanning of the offset phase that results in a sweep of the Raman-shift frequency.Due to high spectral resolution and fast motion-free scanning the technique is beneficial for a number SRS-based applications such as gas sensing and chemical analysis. 展开更多
关键词 COMPOUND spectral resolution
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Quantification of Trace Amounts of Impurities in High Purity Cobalt by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:3
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作者 Hua Lin XIE Xi Du NIE You Gen TANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1077-1080,共4页
An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, ... An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pt, Au and Pb in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCl. The matrix effects due to the presence of excess HCl and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination was tested and discussed. Correction for matrix effects, Sc, Rh and Bi were used as internal standards. The detection limits is 0.003-0.57 μg/g, the recovery ratio is 92.2%-111.2%, and the RSD is less than 3.6%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity cobalt with satisfactory results. 展开更多
关键词 High resolution inductively coupled plasma mass spectrometry high purity cobalt trace impurities matrix effect spectral interference internal standards.
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Direct Determination of Trace Impurities in High Purity Zinc Oxide by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:2
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作者 谢华林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第2期28-32,共5页
The determination of trace impurities in high purity zinc oxide by high resolution inductively coupled plasma mass spectrometry ( HR-ICP-MS ) was investigated. To overcome some poteutially problematic spectral iuter... The determination of trace impurities in high purity zinc oxide by high resolution inductively coupled plasma mass spectrometry ( HR-ICP-MS ) was investigated. To overcome some poteutially problematic spectral iuterference, measurements were acquired in both middle and high resolution modes. The matrix effects due to the presence of excess HCl and zinc were evaluated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits ranged from 0.02μg/ g to 6 μg/ g depending on the elements. The experimental resalts for the determination of Na, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Mo, Cd, Sb and Pb in several high purity zinc oxide powders were presented. 展开更多
关键词 high purity zinc oxide trace impurities high resolution inductively coupled plasma mass spectrometry spectral interferences microwave digestion
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Determination of Trace Elements in High Purity Gold by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:1
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作者 谢华林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第4期608-612,共5页
Trace elements were determined in high purity gold by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Sample were decomposed by aqua regia. To overcome some potentially problematic spectra/... Trace elements were determined in high purity gold by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Sample were decomposed by aqua regia. To overcome some potentially problematic spectra/ interference, measurements were acquired in both medium and high resolution modes. The matrix effects due to the presence of excessive HCl and Au were evaluated. The optimum conditions for the determination was tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits range from 0.01ug/g to 0.28ug/g depending on the elements. The method is accurate, quick and convenient. It has been applied to the determination of trace elements in high purity gold with satisfactory results. 展开更多
关键词 high purity gold trace elements high resolution inductively coupled plasma mass spectrometry spectral interferences
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IMPROVING THE FREQUENCY RESOLUTION OF DIGITALLY SYNTHESIZED PERIODIC SIGNALS BY A SEQUENTIAL ADDRESSING SCHEME 被引量:2
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作者 Tian Xinguang Duan Miyi +1 位作者 Sun Chunlai Chen Hong 《Journal of Electronics(China)》 2008年第5期661-666,共6页
In the digital synthesis of wideband periodic signals using an Arbitrary Waveform Gen-erator(AWG),the frequency resolution and spectral complexity of the synthesized signals are com-monly limited by the memory capacit... In the digital synthesis of wideband periodic signals using an Arbitrary Waveform Gen-erator(AWG),the frequency resolution and spectral complexity of the synthesized signals are com-monly limited by the memory capacity and clock frequency of the AWG.This paper proposes a novel sequential addressing scheme and then presents several sequences to improve the frequency resolution of the synthesized periodic signals without changing their spectral envelopes and basic time-domain characteristics under the condition of a fixed memory capacity and a fixed clock fre-quency.The main idea of the scheme is using the address generator in an AWG to program and produce addresses to read fixed waveform data in variable order,and thus to generate waveforms of various periods and profiles.The scheme is applied in simulating signal scenarios for military com-munication countermeasure experiments,and achieves high performance. 展开更多
关键词 Digital synthesis Frequency resolution spectral envelope Sequential addressing
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Multi-domain High-Resolution Platform for Integrated Spectroscopy and Microscopy Characterizations 被引量:1
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作者 Li Wang Shen-long Jiang +1 位作者 Qun Zhang Yi Luo 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第6期680-685,I0002,共7页
In recent decades,materials science has experienced rapid development and posed increasingly high requirements for the characterizations of structures,properties,and performances.Herein,we report on our recent establi... In recent decades,materials science has experienced rapid development and posed increasingly high requirements for the characterizations of structures,properties,and performances.Herein,we report on our recent establishment of a multi-domain(energy,space,time)highresolution platform for integrated spectroscopy and microscopy characterizations,offering an unprecedented way to analyze materials in terms of spectral(energy)and spatial mapping as well as temporal evolution.We present several proof-of-principle results collected on this platform,including in-situ Raman imaging(high-resolution Raman,polarization Raman,low-wavenumber Raman),time-resolved photoluminescence imaging,and photoelectrical performance imaging.It can be envisioned that our newly established platform would be very powerful and effective in the multi-domain high-resolution characterizations of various materials of photoelectrochemical importance in the near future. 展开更多
关键词 Multi-domain platform spectral/spatial/temporal resolution Integrated characterizations SPECTROSCOPY MICROSCOPY Imaging
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Super-resolution processing of passive millimeter-wave images based on conjugate-gradient algorithm 被引量:1
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作者 Li Liangchao Yang Jianyu Cui Guolong Wu Junjie Jiang Zhengmao Zheng Xin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期762-767,共6页
This paper designs a 3 mm radiometer and validate with experiments based on the principle of passive millimeter wave (PMMW) imaging. The poor spatial resolution, which is limited by antenna size, should be improved ... This paper designs a 3 mm radiometer and validate with experiments based on the principle of passive millimeter wave (PMMW) imaging. The poor spatial resolution, which is limited by antenna size, should be improved by post data processing. A conjugate-gradient (CG) algorithm is adopted to circumvent this drawback. Simulation and real data collected in laboratory environment are given, and the results show that the CG algorithm improves the spatial resolution and convergent rate. Further, it can reduce the ringing effects which are caused by regularizing the image restoration. Thus, the CG algorithm is easily implemented for PMMW imaging. 展开更多
关键词 passive millimeter wave imaging SUPER-resolution conjugate-gradient spectral extrapolation.
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Super-resolution processing of passive millimeter-wave images based on adaptive projected Landweber algorithm 被引量:1
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作者 Zheng Xin Yang Jianyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期709-716,共8页
Passive millimeter wave (PMMW) images inherently have the problem of poor resolution owing to limited aperture dimension. Thus, efficient post-processing is necessary to achieve resolution improvement. An adaptive p... Passive millimeter wave (PMMW) images inherently have the problem of poor resolution owing to limited aperture dimension. Thus, efficient post-processing is necessary to achieve resolution improvement. An adaptive projected Landweber (APL) super-resolution algorithm using a spectral correction procedure, which attempts to combine the strong points of all of the projected Landweber (PL) iteration and the adaptive relaxation parameter adjustment and the spectral correction method, is proposed. In the algorithm, the PL iterations are implemented as the main image restoration scheme and a spectral correction method is included in which the calculated spectrum within the passband is replaced by the known low frequency component. Then, the algorithm updates the relaxation parameter adaptively at each iteration. A qualitative evaluation of this algorithm is performed with simulated data as well as actual radiometer image captured by 91.5 GHz mechanically scanned radiometer. From experiments, it is found that the super-resolution algorithm obtains better results and enhances the resolution and has lower mean square error (MSE). These constraints and adaptive character and spectral correction procedures speed up the convergence of the Landweber algorithm and reduce the ringing effects that are caused by regularizing the image restoration problem. 展开更多
关键词 passive millimeter wave imaging SUPER-resolution Landweber algorithm inverse problems spectral extrapolation.
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Multi-Resolution Fourier Analysis Part II: Missing Signal Recovery and Observation Results
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作者 Nourédine Yahya Bey 《International Journal of Communications, Network and System Sciences》 2012年第1期28-36,共9页
In this paper, we report application procedures and observed results of multi-resolution Fourier analysis proposed in the first part of this series. Missing signal recovery derived from multi-resolution theory is deve... In this paper, we report application procedures and observed results of multi-resolution Fourier analysis proposed in the first part of this series. Missing signal recovery derived from multi-resolution theory is developed. It is shown that multi-resolution Fourier analysis enhances dramatically performances of Fourier spectra suffering limitations traced to implicit time windowing. Observed frequency resolutions, improvement of frequency estimations, contraction of spectral leakage and recovery of missing parts of finite duration signals are in accordance with theoretical predictions. 展开更多
关键词 FOURIER MULTI-resolution spectral Analysis FREQUENCY Estimation FREQUENCY resolution spectral LEAKAGE MISSING Parts Signal Recovery
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Multi-Resolution Fourier Analysis Part I: Fundamentals
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作者 Nourédine Yahya Bey 《International Journal of Communications, Network and System Sciences》 2011年第6期364-371,共8页
In the first paper of this series, we propose a multi-resolution theory of Fourier spectral estimates of finite duration signals. It is shown that multi-resolution capability, achieved without further observation, is ... In the first paper of this series, we propose a multi-resolution theory of Fourier spectral estimates of finite duration signals. It is shown that multi-resolution capability, achieved without further observation, is obtained by constructing multi-resolution signals from the only observed finite duration signal. Achieved resolutions meet bounds of the uncertainty principle (Heisenberg inequality). In the forthcoming parts of this series, multi-resolution Fourier performances are observed, applied to short signals and extended to time-frequency analysis. 展开更多
关键词 MULTI-resolution spectral ANALYSIS FOURIER ANALYSIS resolution Frequency resolution
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