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A Novel Divide and Conquer Solution for Long-term Video Salient Object Detection

Machine Intelligence Research 2024年第4期21卷 684-703页

作者： yun-xiao Li cheng-Li-Zhao chen Shuai Li Ai-Min Hao Hong Qin State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China Department of Computer Science Stony Brook UniversityNew York 11794USA

Recently,a new research trend in our video salient object detection(VSOD)research community has focused on enhancing the detection results via model self-fine-tuning using sparsely mined high-quality keyframes from the given *** such a learning scheme is generally effective,it has a critical limitation,i.e.,the model learned on sparse frames only possesses weak generalization *** situation could become worse on“long”videos since they tend to have intensive scene ***,in such videos,the keyframe information from a longer time span is less relevant to the previous,which could also cause learning conflict and deteriorate the model ***,the learning scheme is usually incapable of handling complex pattern *** solve this problem,we propose a divide-and-conquer framework,which can convert a complex problem domain into multiple simple ***,we devise a novel background consistency analysis(BCA)which effectively divides the mined frames into disjoint *** for each group,we assign an individual deep model on it to capture its key attribute during the fine-tuning *** the testing phase,we design a model-matching strategy,which could dynamically select the best-matched model from those fine-tuned ones to handle the given testing *** experiments show that our method can adapt severe background appearance variation coupling with object movement and obtain robust saliency detection compared with the previous scheme and the state-of-the-art methods.

关键词： Video salient object detection background consistency analysis weakly supervised learning long-term information background shift.

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基于移动作业的电力现场异常智能化稽查方法研究

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自动化技术与应用 2024年第2期43卷 68-71,93页

作者：陈晓云王鹤森朱敏王海龙李学斌国网新疆电力有限公司营销服务中心(资金集约中心、计量中心) 新疆乌鲁木齐830000 宁夏大学数学计算机学院宁夏银川750000

针对电力现场人工稽查危险性高、准确率低的问题,提出基于移动作业的电力现场异常智能化稽查方法。采集电力电场周围的电流变化数据,根据安倍定律得出电缆内外部形成的环形闭合电流。建立空间三点坐标系,计算电缆在三个方向上闭合电流值... 详细信息

针对电力现场人工稽查危险性高、准确率低的问题,提出基于移动作业的电力现场异常智能化稽查方法。采集电力电场周围的电流变化数据,根据安倍定律得出电缆内外部形成的环形闭合电流。建立空间三点坐标系,计算电缆在三个方向上闭合电流值,若电流值超出既定阈值,判定周围存在磁场影响。模拟矩形的稽查空间体,在该空间体中计算待稽查点间位置关系,将位置阈值代入到异常判定矩阵中,输出异常信号位置。实验结果表明,所提方法可充分利用电力现场的暂态数据,稽查结果符合现场实际情况,具有适用性强、稽查覆盖范围广、准确率高的优势。

关键词：移动作业激光扫描电力现场异常稽查暂态数据

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Tunable microwave photonic filter based on a fiber ring and erbium-doped fiber amplifier

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Optoelectronics Letters 2007年第6期3卷 406-409页

作者： FU Hong-yan OU Hai-yan chen Da-ru xiao yun HE Sai-ling Center for Optical and Electromagnetic Research State Key Laboratory of Modern Optical Instrumentation Joint Re-search Center of Optical Communications of Zhejiang University Zhejiang University Hangzhou 310058 China

The tunable microwave photonic filter based on a fiber ring and erbium-doped fiber amplifier （EDFA） was proposed. By introducing a section of erbium-doped fiber （EDF） into the fiber ring, the loss of the signal can be compensated by the EDFA gain through adjusting the pump power. This can largely increase the number of the effective sampling taps, and then improve the performance of the microwave photonic filter notably. When the pump power was set to be 42.7 roW, a microwave bandpass filter with the 3-dB bandwidth of 0.15 MHz, the Q factor up to 100 and extinction ratio up to 20 dB was achieved. By employing a tunable optical delay line in the above fiber ring, a tunable microwave photonic filter has been realized through tuning the length of the optical delay line. The proposed tunable microwave photonic filter can fred great applications in microwave signal processing and ROF system.

关键词：光纤元件微波纤维放大器纤维环

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Effects of water extract from Cornus controversa on the expression levels of DiSOC1-b and DiCCoAOMT1 genes related with the growth of dove tree seedlings

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Journal of Plant Ecology 2024年第2期17卷 62-73页

作者： xiaoyan chen Zhengchuan Liang yun Long Jihong Pan Tingfa Dong Qinsong Liu xiao Xu College of Life Science China West Normal UniversityNanchongSichuan 637009China Key Laboratory of Southwest China Wildlife Resources Conservation(China West Normal University) Ministry of EducationNanchongSichuan 637009China Academy of Agricultural Sciences Liangshan Yi Autonomous PrefectureXichangSichuan 615000China

Although characterization of plant interactions has become a research hotspot to assess the adaptability of endangered plants,the underlying molecular basis remains *** tree(Davidia involucrata)seedlings were watered with distilled water(CK),leaf water extract(0.025 g mL^(-1))and branch water extract(0.1 g mL^(-1))from Cornus controversa,***,the morphology,biomass and gene expression levels of DiSOC1-b and DiCCoAOMT1 were *** results showed that morphological traits and biomass accumulation of *** seedlings were decreased by the addition of leaf water extracts,and increased by branch water ***,the gene expression level of DiSOC1-b was signifcantly down-regulated,while the gene expression level of DiCCoAOMT1 was signifcantly up-regulated in the stems and roots of *** upon treatment with leaf water extracts of *** contrast,the gene expression level of DiSOC1-b was signifcantly up-regulated in the leaves and stems,while the gene expression level of DiCCoAOMT1 was signifcantly down-regulated in the roots of *** upon treatment with branch water extracts of *** addition,the expression level of DiSOC1-b was positively correlated with most of morphological traits and total biomass(P<0.05),while DiCCoAOMT1 was negatively correlated with the majority of morphological traits in *** seedlings(P<0.05).Taken together,these results suggest that water extracts from the leaves and branches of the *** exhibit opposite allelopathic effects and affect the expression levels of genes related to growth(DiSOC1-b)and environmental adaptability(DiCCoAOMT1)in *** seedlings.

关键词： allelopathy Davidia involucrata DiCCoAOMT1 DiSOC1-b water extract

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Study on the clogging mechanism of punching screen in sand control by the punching structure parameters

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Petroleum Science 2024年第1期21卷 609-620页

作者： Fu-cheng Deng Fu-Lin Gui Bai-Tao Fan Lei Wen Sheng-Hong chen Ning Gong yun-chen xiao Zhi-Hui Xu Yangtze University Jingzhou434023HubeiChina CNOOC Research Institute Ltd. Beijing100028China CNOOC Ener Tech-Drilling&Production Co. Tianjin300457China Tianjin Branch of CNOOC Ltd. Tianjin300459China

As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas ***,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the *** explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined *** to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was *** results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of *** the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control *** the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the *** the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage *** microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen

关键词： Punching screen Plugging CFD-DEM Size parameter Sand control

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Construction of electron rich Fe active sites by FeCu alloy anchoring on carbon nitride for photocatalytic nitrogen reduction

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Rare Metals 2024年第4期43卷 1570-1579页

作者： Gang Dong Cong Huang Fei-Yang chen Xue-Qin Liu Zhen Li xiao-Li Su Tao Zeng yun-Xia chen Yi-Huang chen Yang Wang School of Materials Science and Engineering Jingdezhen Ceramic UniversityJingdezhen333403China Faculty of Materials Science and Chemistry China University of GeosciencesWuhan430074China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China

Given the clean and inexhaustible solar energy from solar light,photocatalytic ammonia synthesis is extremely ***,high electron-hole recombination rates and insufficient active sites severely limited N2 photoreaction ***,we designed and fabricated FeCu alloy nanoparticles anchored on carbon nitride nanosheets with excellent photocatalyt ic ammonia synthesis *** a coupler between Fe and carbon nitride,Cu promotes the separation of photogenerated charge carriers in carbon nitride under solar light irradiation,and renters the semiconductor a forceful electron donor for the Fe active *** accumulated electrons at Fe sites furtherly facilitated the adsorption and activation of the molecular ***,the uniform dispersed FeCu alloy nanoparticles were on carbon nitride nanosheets enhanced the stability of photocataly tic nitrogen reduction reaction,making the artificial photocataly tic ammonia synthesis more sustainable for *** work highlights that a direct electron transfer channel can be used to regulate the photochemical nitrogen fixation network.

关键词： Photocatalytic N_2 fixation Carbon nitride FeCu alloy Active sites Hydrogenation pathway

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子空间结构保持的多层极限学习机自编码器

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自动化学报 2022年第4期48卷 1091-1104页

作者：陈晓云陈媛福州大学数学与计算机科学学院福州350116

处理高维复杂数据的聚类问题,通常需先降维后聚类,但常用的降维方法未考虑数据的同类聚集性和样本间相关关系,难以保证降维方法与聚类算法相匹配,从而导致聚类信息损失.非线性无监督降维方法极限学习机自编码器(Extreme learning machin... 详细信息

处理高维复杂数据的聚类问题,通常需先降维后聚类,但常用的降维方法未考虑数据的同类聚集性和样本间相关关系,难以保证降维方法与聚类算法相匹配,从而导致聚类信息损失.非线性无监督降维方法极限学习机自编码器(Extreme learning machine,ELM-AE)因其学习速度快、泛化性能好,近年来被广泛应用于降维及去噪.为使高维数据投影至低维空间后仍能保持原有子空间结构,提出基于子空间结构保持的多层极限学习机自编码器降维方法(Multilayer extreme learning machine autoencoder based on subspace structure preserving,ML-SELM-AE).该方法在保持聚类样本多子空间结构的同时,利用多层极限学习机自编码器捕获样本集的深层特征.实验结果表明,该方法在UCI数据、脑电数据和基因表达谱数据上可以有效提高聚类准确率且取得较高的学习效率.

关键词：多层极限学习机自编码器子空间学习降维

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Production of Transgenic Tall Fescue Plants with Enhanced Stress Tolerances by Agrobacterium tumefaciens-Mediated Transformation

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Agricultural Sciences in China 2006年第5期5卷 330-338页

作者： WU Guan-ting chen Jin-qing HU Zhang-hua LANG Chun-xiu chen xiao-yun WANG Fu-lin JIN Wei XIA Ying-wu Institute of Virology and Biotechnology Zhejiang Academy of Agricultural Sciences Hangzhou 310021 P.R. China Institute of Nuclear-Agricultural Sciences Zhejiang University Hangzhou 310029 P.R. China

In order to improve stress tolerances of turf-type tall fescue （Festuca arundinacea Schreb.）, Agrobacterium tumefaciens strain EHA105 carrying plasmid pCMD containing stress tolerance-related CBF1 gene from Arabidopsis thaliana was used to transform mature seeds-derived embryogenic calli of four cultivars. A total of 112 transgenic plants were regenerated from 32 independent lines and verified by histochemical detection of GUS activity, PCR assay and Southern hybridization analysis. The transformation frequency ranged from 0.92 to 2.87% with apparent differences among the cultivars. Stress tolerances of transgenic plants were enhanced, which was shown by the facts that transgenic plants had distinct growth superiority and significantly higher survival rate than non-transformed ones under high salinity and high osmosis stresses, and that relative electronic conductivity of in vitro leaves treated with low and high temoeratures, dehvdration and high salinity stresses was 25-30% lower in transgenic plants than in control *** addition,it was observed that growth of transgenic plants was inhibited due to constitutive overexpression of CBF1 gene under normal environmental conditions.

关键词： tall fescue (Festuca arundinacea Schreb.) Agrobacterium tumefaciens genetic transformation CBF1 gene stress tolerance

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A Post-Quantum Cross-Domain Authentication Scheme Based on Multi-Chain Architecture

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Computers, Materials & Continua 2024年第2期78卷 2813-2827页

作者： Yi-Bo Cao Xiu-Bo chen yun-Feng He Lu-Xi Liu Yin-Mei Che xiao Wang Ke xiao Gang Xu Si-Yi chen Information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China Information Center of China North Industries Group Corporation Beijing100089China School of Information Science and Technology North China University of TechnologyBeijing100144China

Due to the rapid advancements in network technology,blockchain is being employed for distributed data *** the Internet of Things(IoT)scenario,different participants manage multiple blockchains located in different trust domains,which has resulted in the extensive development of cross-domain authentication ***,the emergence of many attackers equipped with quantum computers has the potential to launch quantum computing attacks against cross-domain authentication schemes based on traditional cryptography,posing a significant security *** response to the aforementioned challenges,our paper demonstrates a post-quantum cross-domain identity authentication scheme to negotiate the session key used in the cross-chain asset exchange ***,our paper designs the hiding and recovery process of user identity index based on lattice cryptography and introduces the identity-based signature from lattice to construct a post-quantum cross-domain authentication ***,our paper utilizes the hashed time-locked contract to achieves the cross-chain asset exchange of blockchain nodes in different trust ***,the security analysis reduces the security of the identity index and signature to Learning With Errors(LWE)and Short Integer Solution(SIS)assumption,respectively,indicating that our scheme has post-quantum *** but not least,through comparison analysis,we display that our scheme is efficient compared with the cross-domain authentication scheme based on traditional cryptography.

关键词： Cross-domain identity authentication lattice-based cryptography blockchain hashed time-locked contract

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Therapeutic effect of manual massage on early postpartum rectus abdominis separation and postpartum depression

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World Journal of Psychiatry 2024年第5期14卷 678-685页

作者： yun chen xiao-Yan Sun cheng Qian xiao-Xing Zhang Yin-Jian Zhou Hong-yun Zhang Zhen-Wei Xie Department of Gynecology Women’s Hospital School of Medicine Zhejiang UniversityHangzhou 310006Zhejiang ProvinceChina Department of Obstetrics and Gynecology Huzhou Maternity and Child Health Care HospitalHuzhou 313000Zhejiang ProvinceChina Department of Surgery Huzhou Maternity and Child Health Care HospitalHuzhou 313000Zhejiang ProvinceChina Department of Obstetrics Huzhou Maternity and Child Health Care HospitalHuzhou 313000Zhejiang ProvinceChina Department of Ultrasound Women’s Hospital School of Medicine Zhejiang UniversityHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Rectus abdominis separation(DRA)affects pelvic stability and body *** studies have explored the effects of manual massage on early postpartum DRA and postpartum *** To analyze the curative effect of massage on early postpartum DRA and its impact on postpartum depression and thus its ability promote the overall psychosomatic rehabilitation of postpartum *** Data were retrospectively collected on 70 primiparous women with postpartum DRA who underwent rehabilitation at the Postpartum Rehabilitation Center of Huzhou Maternal and Child Health Hospital from October 2022 to September *** patients were divided into the Group S(35 cases,biomimetic electrical stimulation treatment)and Group L(35 cases,biomimetic electrical stimulation combined with manual massage treatment).Baseline data,the edinburgh postpartum depression scale(EPDS)score,and the visual analog scale(VAS)scores for rectus abdominis distance,waist circumference,and lower back pain before and after treatment were *** No significant differences were found in the baseline data,rectus abdominis distance,waist circumference,and VAS and EPDS scores between the two groups before treatment(P>0.05).After treatment,the distance between rectus abdominis and waist circumference in Group L were significantly smaller than those in Group S(P<0.05).Furthermore,lower back pain(VAS score)and the EPDS score in Group L were significantly lower than those in Group S(P<0.05).CONCLUSION Manual massage can significantly reduce early postpartum DRA,waist circumference,and back pain and improve the patient’s mental state and postpartum depression.

关键词： Manual massage Postpartum Rectus abdominis muscle separation Postpartum depression

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