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Science China(information Sciences) 2024年第3期67卷 271-280页

作者： Shuiying XIANG Shuang GAO Yuechun SHI Yuna ZHANG Ziwei SONG Xingxing GUO Yahui ZHANG Yuxin MA Xiangfei CHEN State Key Laboratory of Integrated Service Networks Xidian University Yongjiang Laboratory 3. college of Engineering and Applied Sciences Nanjing University

We proposed and experimentally demonstrated a simple and novel photonic spiking neuron based on a distributed feedback(DFB) laser subject to side-mode optical pulse injection(SMOPI). The DFB laser chip is designed and fabricated based on asymmetric equivalent π phase shift(π-EPS) with the reconstruction-equivalent-chirp(REC) technique. Under side-mode continuous-wave(CW) optical injection,excitability pulse was experimentally observed during the dominant mode switching process due to the injection-locked effect. Based on the transition between the excitability regime and the side-mode injection locking effect, the controllable and repeatable neuron-like spiking response can be realized when external stimulus pulses are electro-optically modulated on the CW optical carrier. The experimental results show that the spike threshold, temporal integration, and refractory period, which are important spike processing mechanisms in biological neurons, can all be achieved in the optically-injected DFB laser. The experimental findings are also verified numerically with a rate equation model that considers the SMOPI. To the best of our knowledge, this is the first experimental demonstration of a photonic spiking neuron based on a DFB laser subject to SMOPI, which holds promise for realizing large-scale photonic spiking neuron arrays for hardware photonic spiking neural network chips.

关键词： neuromorphic photonics photonic spiking neuron DFB laser side-mode optical pulse injections

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

Paving the way toward soil safety and health:current status,challenges,and potential solutions

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 63-73页

作者： Chiheng Chu Lizhong Zhu college of Environmental and resource Sciences Zhejiang UniversityHangzhou 310058China

Soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon ***,the health of soil faces global threats from human activities,particularly widespread contamination by industrial *** physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional *** solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale ***,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of ***,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring *** the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

关键词： Soil safety and health Source emission reduction Process monitoring and simulation Green remediation technology Soil health management

Integrating remote sensing and 3.PG model to simulate the biomass and carbon stock of Larix olgensis plantation

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Forest Ecosystems 2024年第4期11卷 543-555页

作者： Yu Bai Yong Pang Dan Kong Key Laboratory of National Forestry and Grassland Administration on Forestry Remote Sensing and information System Institute of Forest Resource Information

Accurate estimations of biomass and its temporal dynamics are crucial for monitoring the carbon cycle in forest ecosystems and assessing forest carbon sequestration *** studies have shown that integrating process-based models(PBMs)with remote sensing data can enhance simulations from stand to regional scales,significantly improving the ability to simulate forest growth and carbon stock ***,the utilization of PBMs for large-scale simulation of larch carbon storage distribution is still *** this study,we applied the parameterized 3.PG(Physiological Principles Predicting Growth)model across the Mengjiagang Forest Farm(MFF)to make broad-scale predictions of the biomass and carbon stocks of Larix olgensis *** model was used to simulate average diameter at breast height(DBH)and total biomass,which were later validated with a wide range of observation data including sample plot data,forest management inventory data,and airborne laser scanning *** results showed that the 3.PG model had relatively high accuracy for predicting both DBH and total biomass at stand and regional scale,with determination coefficients ranging from 0.78 to *** on the estimation of total biomass,we successfully produced a carbon stock map of the Larix olgensis plantation in MFF with a spatial resolution of 20 m,which helps with relevant management *** findings indicate that the integration of 3.PG model and remote sensing data can well predict the biomass and carbon stock at regional and even larger *** addition,this integration facilitates the evaluation of forest carbon sequestration capacity and the development of forest management plans.

关键词： 3.PG model Larch Biomass Carbon stock ALS

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Microplastics may reduce the fish bioaccumulation of organic pollutants

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Science China Technological Sciences 2024年第10期67卷 3079-3090页

作者： YANG Bing ZHOU Xian HU XiaoJie QIN Chao WANG Jian GAO YanZheng Institute of Organic Contaminant Control and Soil Remediation College of Resource and Environmental SciencesNanjing Agricultural University

Microplastics have frequently been regarded as a threat to aquatic organisms due to their potential to enhance the accessibility of organic pollutants. However, studies of microplastics as “carriers” in the process of bioaccumulation have only been conducted on a few organic contaminants. In this study, we employed machine learning algorithms to predict the sorption capacity of 83.exogenous organic pollutants(in CCL4) on microplastics, the prediction model exhibits exceptional predictive performance,achieving R2values of 0.8651 and 0.6962, RMSE values of 0.4625 and 0.1841 for the sorption coefficients Kfand n, respectively,and quantitatively estimated the contribution of microplastics to the bioaccumulation levels of organic pollutants in Gadus morhua. By considering both natural and microplastic-ingesting pathways, we demonstrated that the ingestion of microplastics containing organic pollutants facilitates the entry of organic pollutants into Gadus morhua. However, due to their robust sorption capacity, microplastics transport the organic pollutants accumulated through the natural pathway out of the fish, thereby preventing bioaccumulation. These findings elucidate the “cleaning” mechanism of microplastics concerning various organic pollutants in aquatic organisms, providing valuable insights for accurately assessing the risk of microplastics in aquatic environments.

关键词： microplastics aquatic organisms organic pollutants machine learning risks

A mixed Nash equilibrium solution for visibility-based pursuit-evasion game with multiple obstacles

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Science China(information Sciences) 2024年第9期67卷 330-332页

作者： Shaoming BU Li LIANG Youqing WANG college of information Science and Technology Beijing University of Chemical Technology

This study primarily investigates a visibility-based pursuitevasion game with multiple obstacles. The pursuer aims to maintain surveillance over the evader as long as possible, while the evader's objective is to escape the pursuer's surveillance as quickly as possible. We use the explicit strategy method to analyze the winning conditions and optimal strategy of the player in the case of corner obstacles and propose a 'Present-Future-Past'(PFP) loop structure to extend the strategy to the case of multiple obstacles.

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DCVAE-adv:A Universal Adversarial Example Generation Method for White and Black Box Attacks

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Tsinghua Science and Technology 2024年第2期29卷 430-446页

作者： Lei Xu Junhai Zhai college of Mathematics and information Science Hebei UniversityBaoding 071002China

Deep neural network(DNN)has strong representation learning ability,but it is vulnerable and easy to be fooled by adversarial *** order to handle the vulnerability of DNN,many methods have been *** general idea of existing methods is to reduce the chance of DNN models being fooled by observing some designed adversarial examples,which are generated by adding perturbations to the original *** this paper,we propose a novel adversarial example generation method,called *** from the existing methods,DCVAE-adv constructs adversarial examples by mixing both explicit and implicit perturbations without using original ***,the proposed method can be applied to both white box and black box *** addition,in the inference stage,the adversarial examples can be generated without loading the original images into memory,which greatly reduces the memory *** compared DCVAE-adv with three most advanced adversarial attack algorithms:FGSM,AdvGAN,and AdvGAN++.The experimental results demonstrate that DCVAE-adv is superior to these state-of-the-art methods in terms of attack success rate and transfer ability for targeted *** code is available at https://***/xzforeverlove/DCVAE-adv.

关键词： deep neural network adversarial examples white box attack black box attack robustness

Engineering the spectra of photon triplets generated from micro/nanofiber

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Chinese Physics B 2024年第3期33卷 408-414页

作者：瞿川郭东琴李笑笑刘振旗赵义张胜海卫正统 The college of Basic Department Information Engineering UniversityZhengzhou 450000China

Quantum light sources are the core resources for photonics-based quantum information *** investigate the spectral engineering of photon triplets generated by third-order spontaneous parametric down-conversion in micro/*** phase mismatching at one-third pump frequency gives rise to non-degenerate photon triplets,the joint spectral intensity of which has an elliptical locus with a fixed eccentricity of√6/***,we propose a frequency-division scheme to separate non-degenerate photon triplets into three channels with high heralding efficiency for the first *** an appropriate pump wavelength can compensate for the fabrication errors of micro/nanofiber and also generate narrowband,non-degenerate photon triplet sources with a high signal-to-noise ***,the long-period micro/nanofiber grating introduces a new controllable degree of freedom to tailor phase matching,resulting from the periodic oscillation of *** this scheme,the wavelength of photon triplets can be flexibly tuned using quasi-phase *** study the generation of photon triplets from this novel perspective of spectrum engineering,and we believe that this work will accelerate the practical implementation of photon triplets in quantum information processing.

关键词： photon triplets micro/nanofiber spectrum engineering

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Identification of rural courtyards’utilization status using deep learning and machine learning methods on unmanned aerial vehicle images in north China

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Building Simulation 2024年第5期17卷 799-818页

作者： Maojun Wang Wenyu Xu Guangzhong Cao Tao Liu college of resource Environment and Tourism Capital Normal UniversityBeijing 100048China college of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The issue of unoccupied or abandoned homesteads(courtyards)in China emerges given the increasing aging population,rapid urbanization and massive rural-urban *** the aspect of rural vitalization,land-use planning,and policy making,determining the number of unoccupied courtyards is *** and questionnaire-based surveys were currently the main approaches,but these traditional methods were often expensive and laborious.A new workflow is explored using deep learning and machine learning algorithms on unmanned aerial vehicle(UAV)***,features of the built environment were extracted using deep learning to evaluate the courtyard management,including extracting complete or collapsed farmhouses by Alexnet,detecting solar water heaters by YOLOv5s,calculating green looking ratio(GLR)by *** precisions exceeded 98%.Then,seven machine learning algorithms(Adaboost,binomial logistic regression,neural network,random forest,support vector machine,decision trees,and XGBoost algorithms)were applied to identify the rural courtyards’utilization *** Adaboost algorithm showed the best performance with the comprehensive consideration of most metrics(Accuracy:0.93.,Precision:0.93.,Recall:0.984,F1-score:0.957).Results showed that identifying the courtyards’utilization statuses based on the courtyard built environment is *** is transferable and cost-effective for large-scale village surveys,and may contribute to the intensive and sustainable approach to rural land use.

关键词： unoccupied homesteads courtyard built environment inner courtyard management GLR solar water heaters machine learning algorithms

Product quality prediction based on RBF optimized by firefly algorithm

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Journal of Systems Engineering and Electronics 2024年第1期35卷 105-117页

作者： HAN Huihui WANG Jian CHEN Sen YAN Manting college of Electronics and information Engineering Tongji UniversityShanghai 201804China

With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used *** traditional product quality prediction models have many disadvantages,such as high complexity and low *** overcome the above problems,we propose an optimized data equalization method to pre-process dataset and design a simple but effective product quality prediction model:radial basis function model optimized by the firefly algorithm with Levy flight mechanism(RBFFALM).First,the new data equalization method is introduced to pre-process the dataset,which reduces the dimension of the data,removes redundant features,and improves the data *** the RBFFALFM is used to predict product *** expe riments conducted on real-world product quality datasets validate that the new model RBFFALFM combining with the new data pre-processing method outperforms other previous me thods on predicting product quality.

关键词： product quality prediction data pre-processing radial basis function swarm intelligence optimization algorithm

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