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Photonics Research 2024年第7期12卷 1395-1409页

作者： XIMING LI RUI XU XIAOFENG SUN YUAN ZHAO ZHAO YANG GUOHONG DU college of Electronic engineering Chengdu University of Information TechnologyChengdu 610225China

Programmable metasurfaces have received a great deal of attention due to their ability to dynamically manipulate electromagnetic(EM) waves. Despite the rapid growth, most of the existing metasurfaces require manual control to switch among different functionalities, which poses severe limitations on practical applications. Here, we put forth an intelligent metasurface that has self-adaptive EM functionality switching in broadband without human participation. It is equipped with polarization discrimination antennas(PDAs) and feedback components to automatically adjust functionalities for the different incident polarization information.

关键词： equipped adjust polarization

Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer

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Nuclear Science and Techniques 2024年第2期35卷 64-84页

作者： Chun-Di Fan Guo-Qiang Zeng Hao-Wen Deng Lei Yan Jian Yang Chuan-Hao Hu Song Qing Yang Hou college of Nuclear technology and Automation engineering Chengdu University of TechnologyChengdu 610059China

To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement ***,the complex and expensive hardware required does not facilitate the application or promotion of this ***,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and *** electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition *** relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature *** accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the *** learning is used to input the four shape parameters into the ***,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition *** partial-energy deposition events are removed to suppress Compton *** proposed method effectively decreases the MDA of an HPGeγ-energy dispersive *** results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.

关键词： High-purity germaniumγ-ray spectrometer Pulse-shape discrimination Compton scattering Artificial neural network Minimum detectable activity

Multi-Level Parallel Network for Brain Tumor Segmentation

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Computer Modeling in engineering & Sciences 2024年第4期139卷 741-757页

作者： Juhong Tie Hui Peng School of Software engineering Chengdu University of Information TechnologyChengdu610225China

Accurate automatic segmentation of gliomas in various sub-regions,including peritumoral edema,necrotic core,and enhancing and non-enhancing tumor core from 3D multimodal MRI images,is challenging because of its highly heterogeneous appearance and *** convolution neural networks(CNNs)have recently improved glioma segmentation ***,extensive down-sampling such as pooling or stridden convolution in CNNs significantly decreases the initial image resolution,resulting in the loss of accurate spatial and object parts information,especially information on the small sub-region tumors,affecting segmentation ***,this paper proposes a novel multi-level parallel network comprising three different level parallel subnetworks to fully use low-level,mid-level,and high-level information and improve the performance of brain tumor *** also introduce the Combo loss function to address input class imbalance and false positives and negatives imbalance in deep *** proposed method is trained and validated on the BraTS 2020 training and validation *** the validation dataset,ourmethod achieved a mean Dice score of 0.907,0.830,and 0.787 for the whole tumor,tumor core,and enhancing tumor core,*** with state-of-the-art methods,the multi-level parallel network has achieved competitive results on the validation dataset.

关键词： Convolution neural network brain tumor segmentation parallel network

Tailoring crystallization zinc hydroxide sulfates growth towards stable zinc deposition chemistry

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Nano Research 2024年第6期17卷 5243-5250页

作者： Kaixin Huang Xianguang Zeng Dan Zhang Yujie Wang Mu Lan Chengyan Wen Yi Guo college of Materials Science and engineering Sichuan University of Science and EngineeringZigong 643000China Department of Chemistry College of Resource and EnvironmentBaoshan UniversityBaoshan 678000China college of Optoelectronic engineering Chengdu University of Information TechnologyChengdu 610225China

The unstable zinc anode/electrolyte interface induced by corrosion,interfacial water splitting reaction,and dendrite growth seriously degrades the performances of metal Zn anode in aqueous ***,the nucleation and growth of zinc hydroxide sulfate(ZHS),an interfacial by-product,has been tailored by Tween 80 in the electrolyte,which thereby assists in in-situ forming a dense solid electrolyte interphase(SEI)with small-sized ZHS and evenly distributed Tween *** SEI has high corrosion resistance and uniform distribution of zinc ions,which not only contributes to blocking the interfacial side reactions but also induces stable and calm zinc plating/***,the modified electrolyte can confer the assembled Zn||Zn symmetric cell with a stable operation life over 1500 h at 1 mA·cm^(−2)and 1 mAh·cm^(−2)as well as the practical Zn||NH4V4O10 full battery with a high-rate capacity of 120 mAh·g^(−1)at the current density of 5 A·g^(−1).This work provides a way for regulating and reusing interfacial by-products,and a new sight on stabilization electrodes/electrolyte interfaces.

关键词： zinc hydroxide sulfides tailoring crystallization in-situ solid electrolyte interphase electrolyte engineering strategy aqueous zinc-ion battery

Viscoacoustic generalized screen propagator in constant-Q model

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Petroleum Science 2024年第4期21卷 2356-2369页

作者： Zhong-Kui Dai Jia-Chun You Xing-Guo Huang Wei Liu college of Geophysics Chengdu University of Technology college of Instrumentation and Electrical engineering Jilin University

When seismic waves propagate through the geological formation, there is a significant loss of energy and a decrease in imaging resolution, because of the viscoacoustic properties of subsurface medium. This profoundly impacts seismic wavefield propagation, imaging and interpretation. To accurately image the true structure of subsurface medium, the consensus among geophysicists is to no longer treat subsurface medium as ideal homogeneous medium, but rather to incorporate the viscoacoustic properties of subsurface medium. Based on the generalized screen propagator using conventional acoustic wave equation(acoustic GSP), our developed method introduces viscoacoustic compensation strategy, and derives a one-way wave generalized screen propagator based on time-fractional viscoacoustic wave equation(viscoacoustic GSP). In numerical experiments, we conducted tests on two-dimensional multi-layer model and the Marmousi model. When comparing with the acoustic GSP using the acoustic data, we found that the imaging results of the viscoacoustic GSP using the viscoacoustic data showed a significant attenuation compensation effect, and achieved imaging results for both algorithms were essentially consistent. However, the imaging results of acoustic GSP using viscoacoustic data showed significant attenuation effects, especially for deep subsurface imaging. This indicates that we have proposed an effective method to compensate the attenuated seismic wavefield. Our application on a set of real seismic data demonstrated that the imaging performance of our proposed method in local areas surpassed that of the conventional acoustic GSP. This suggests that our proposed method holds practical value and can more accurately image real subsurface structures while enhancing imaging resolution compared with the conventional acoustic GSP. Finally, with respect to computational efficiency, we gathered statistics on running time to compare our proposed method with conventional Q-RTM, and it is evid

关键词： One-way wave equation Viscoacoustic wave equation Generalized screen propagator Attenuation and dispersion effects

A study of a blockchain-based judicial evidence preservation scheme

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Blockchain(Research and Applications) 2024年第2期5卷 151-162页

作者： Shuaiqi Liu Qingxiao Zheng Industry college of Blockchain technology Chengdu University of Information TechnologyChengdu610103China

To address the challenges of low credibility,difficult data sharing,and regulatory supervision issues involving electronic evidence storage in the judicial preservation process,this paper proposes a blockchain-based judicial evidence preservation *** scheme utilizes the characteristics of blockchain’s immutability to achieve credible forensics of electronic evidence on the chain and employs the decentralized storage of the interplanetary file system for secure and efficient off-chain ***,it resolves the problem of declining throughput due to limited block ***,it leverages smart contract technology to encompass major aspects of the judicial process,including user case registration,authority management,judicial evidence uploading and downloading,case data sharing,partial disclosure of case information,and regulatory *** experiments demonstrate that the scheme significantly improves throughput and *** tests indicate that the transfer speed of the interplanetary file system can meet the data-sharing needs of judicial organizations.

关键词： Blockchain Judicial preservation Smart contracts Interplanetary file system

Imaging through scattering layers using a near-infrared low-spatial-coherence fiber random laser

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Chinese Physics B 2024年第10期33卷 226-232页

作者： Anda Shi Zeyu Wang Chenxi Duan Zhao Wang Weili Zhang School of information and Communication engineering University of Electronic Science&Technology of ChinaChengdu 611731China Yingcai Honors college University of Electronic Science&Technology of ChinaChengdu 611731China

Optical memory effect-based speckle-correlated technology has been developed for reconstructing hidden objectsfrom disordered speckle patterns,achieving imaging through scattering ***,the lighting efficiency and fieldof view of existing speckle-correlated imaging systems are ***,a near-infrared low spatial coherence fiberrandom laser illumination method is proposed to address the above *** the utilization of random Rayleighscattering within dispersion-shifted fibers to provide feedback,coupled with stimulated Raman scattering for amplification,a near-infrared fiber random laser exhibiting a high spectral density and extremely low spatial coherence is *** on the designed fiber random laser,speckle-correlated imaging through scattering layers is achieved,with highlighting efficiency and a large imaging field of *** work improves the performance of speckle-correlated imagingand enriches the research on imaging through scattering medium.

关键词： fiber random laser speckle-correlated imaging scattering medium spatial coherence

A hybrid WUDT-NAFnet for simultaneous source data deblending

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Petroleum Science 2024年第3期21卷 1649-1659页

作者： Chao-Fan Ke Shao-Huan Zu Jun-Xing Cao Xu-Dong Jiang Chao Li Xing-Ye Liu Key Laboratory of Earth Exploration and information technology of Ministry of Education Chengdu University of Technology State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology college of Geophysics Chengdu University of Technology

Simultaneous source technology,which reduces seismic survey time and improves the quality of seismic data by firing more than one source with a narrow time interval,is compromised by the massive blended ***,deblending algorithms have been developed to separate this ***,deep learning(DL)has been proved its great potential in suppressing the *** most popular DL method employs neural network as a filter to attenuate the blended noise in an iterative estimation and subtraction framework(IESF).However,there are still amplitude distortion and blended noise residual problems,especially when dealing with weak signal submerged in strong *** address these problems,we propose a hybrid WUDT-NAFnet,which contains two *** first network is a wavelet based U-shape deblending transformer network(WUDTnet),incorporated into IESF as a robust regularization term to iteratively separate the blended *** second network is a nonlinear activate free network(NAFnet)designed to recover the event amplitude and further suppress the weak noise residual in *** the hybrid network,the blended noise can be separated purposefully and *** using synthetic and field seismic data demonstrate that the WUDTNAFnet outperforms traditional curvelet transform(CT)based method and the deblending transformer(DT)model in terms of ***,for field applications,the data augmentation method of bicubic interpolation is applied to mitigate the feature difference between synthetic and field ***,the trained network exhibits strong signal preservation ability in numerical field example without requiring additional training.

关键词： Simultaneous-source Deblending Deep learning Transformer

Full bandwidth statistical properties of the Raman random fiber laser

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Chinese Optics Letters 2024年第6期22卷 142-147页

作者： Jiaojiao Zhang Shengtao Lin Xingyu Bao Pan Wang Yifei Qi Han Wu Jing Liang Zinan Wang Key Laboratory of Optical Fiber Sensing and Communications University of Electronic Science and Technology of ChinaChengdu 611731China college of Electronics and information engineering Sichuan UniversityChengdu 610064China

The Raman random fiber laser (RRFL) is a typical complex physical system due to the intrinsic random feedback of the fiber,which causes complexity in the RRFL output. So far, the time-domain statistical attributes of the RRFL are still not fully characterized. In this paper, the temporal statistical properties of the RRFL are investigated comprehensively for the first time under the full bandwidth condition. First, the time-domain intensity statistical characteristics of the RRFL under the full bandwidth condition are theoretically studied: the results demonstrate that the intensity probability density function of the RRFL is related to the pump power and observing position and deviates inward from the exponential distribution, indicating that correlation exists between the different frequency components in the spectrum. Afterward, in the validation experiment, an elaborate structure is designed to realize a narrow-bandwidth 1053 nm RRFL, and its full bandwidth temporal intensity statistical features manifest an identical variation pattern to the simulation results. This work fills a vacancy in the study of RRFL temporal statistical features and rigorously reveals the different physical mechanisms between RRFL and amplified spontaneous emission light sources, providing instructions for the application of the RRFL.

关键词： random-distributed-feedback fiber laser Raman gain Rayleigh scattering statistical analysis

Time-dependent model for two-phase flow in ultra-high water-cut reservoirs: Time-varying permeability and relative permeability

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Petroleum Science 2024年第4期21卷 2536-2553页

作者： Shao-Chun Wang Na Zhang Zhi-Hao Tang Xue-Fei Zou Qian Sun Wei Liu college of Energy Resources Chengdu University of Technology college of Petroleum engineering Shandong Institute of Petroleum and Chemical Technology

For the ultra-high water-cut reservoirs, after long-term water injection exploitation, the physical properties of the reservoir change and the heterogeneity of the reservoir becomes increasingly severe, which further aggravates the spatial difference of the flow field. In this study, the displacement experiments were employed to investigate the variations in core permeability, porosity, and relative permeability after a large amount of water injection. A relative permeability endpoint model was proposed by utilizing the alternating conditional expectation(ACE) transformation to describe the variation in relative permeability based on the experimental data. Based on the time dependent models for permeability and relative permeability, the traditional oil-water two-phase model was improved and discretized using the mimetic finite difference method(MFD). The two cases were launched to confirm the validation of the proposed model. The impact of time-varying physical features on reservoir production performance was studied in a real water flooding reservoir. The experimental results indicate that the overall relative permeability curve shifts to the right as water injection increases. This shift corresponds to a transition towards a more hydrophilic wettability and a decrease in residual oil saturation. The endpoint model demonstrates excellent accuracy and can be applied to time-varying simulations of reservoir physics. The impact of variations in permeability and relative permeability on the reservoir production performance yields two distinct outcomes. The time-varying permeability of the reservoir results in intensified water channeling and poor development effects. On the other hand, the time-varying relative permeability enhances the oil phase seepage capacity, facilitating oil displacement. The comprehensive time-varying behavior is the result of the combined influence of these two parameters, which closely resemble the actual conditions observed in oil field expl

关键词： Mimetic finite difference Water flooding reservoir Time-varying physical properties Numerical simulation