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Utilizing BP neural networks to accurately reconstruct the tritium depth profile in materials for BIXS

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Nuclear Science and Techniques 2025年第1期36卷 103-114页

作者： Chen Zhao wei Jin Yan shi Chang-An Chen yi-ying Zhao Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China

β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample ***,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this *** this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is *** average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium ***,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.

关键词： β-ray-induced X-ray spectroscopy Tritium detection BP network Ridge regression Reconstruction problem

A NEW CALCULATION METHOD FOR GAS-WELL LIQUID LOADING CAPACITY

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Journal of Hydrodynamics 2010年第6期22卷 823-828页

作者： WANG yi-wei ZHANG shi-cheng YAN Jin CHEN Wen-bin Ministry of Education Key Laboratory of Petroleum Engineering China University of Petroleum Beijing 102249 Petroleum Exploration and Production Research Institute S1NOPEC Beijing 100083 China Sinochem Petroleum Exploitation and Production Co. Ltd Beijing 100031 china

This article proposes a new model for calculating the gas-well liquid loading capacity, which is critical to an accurate prediction of gas well production. Based on analysis of flow regime during the gas well production with water, which is regarded as many single particles in the model, with the shape of particles being assumed as disk-like ellipsoid instead of traditional sphere and changing according to the forces exerted on them, the influences of non-Darcy flow, compressibility, and non-sphere shape on friction factor are analyzed. The differences between the new model and other models are discussed and a new formula for calculating the critical flow rate is obtained. The calculation results and a comparison with other two models show that the new model is more consistent with the actual situation and is practical.

关键词： gas well accumulated liquid drag factor critical flow rate

Use of forestry waste as an alternative raw material for generating metallurgical coke

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Journal of Iron and Steel Research International 2025年第1期32卷 25-39页

作者： Lin-bo Qin wei Qin An-yi Wang Ling shi Jun Han College of Resources and Environment Engineering Wuhan University of Science and TechnologyWuhan430081HubeiChina Hubei Key Laboratory of Industrial Fume and Dust Pollution Control Jianghan UniversityWuhan430056HubeiChina Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan University of Science and TechnologyWuhan430081HubeiChina

Forestry waste(FW)is a significant renewable energy source in *** substitution of coal blends(BC)with forestry waste to produce metallurgical coke was investigated aiming at expanding alternative resources and reducing CO_(2)emissions in ironmaking *** BC with different ratios of FW were carbonized in a fixed bed reactor,and the physicochemical structure of the coke derived from FW/BC co-carbonization was characterized by Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,solid-state^(13)C nuclear magnetic resonance,optical microscopy,and scanning electron *** results reveal that the suitable incorporation of FW in BC is 10 wt.%,and the index of coke quality exhibits a good correlation with the optical anisotropy index and the aromaticity of the as-obtained *** partial substitution of BC with FW exhibits potential benefits for colloid formation,owing to the higher hydrogen in ***,as the substitution ratio of BC with FW increases,it inhibits coke agglomeration due to more tortuous stacked structures formation during volatile releasing ***,it was identified that the substitution of higher BC ratios with FW results in the partial replacement of aromatic carbons by oxygenlinked carbons and aliphatic *** substitution leads to a reduction in the aromaticity of the as-obtained coke.

关键词： Metallurgical coke Forestry waste Coal blend Co-carbonization Chemical structure

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断陷盆地岩性地层油藏分布特征

石油学报 2005年第1期26卷 38-41页

作者：易士威成都理工大学

近几年对二连盆地、冀中坳陷岩性及地层油藏的勘探研究结果表明,与构造油藏相比,由于圈闭形成机制的不同和成藏控制因素的差异,岩性、地层油藏主要沿“湖泛面、不整合面、断面”分布;既可分布于低势区,也可分布于高势区;既可发育于低位... 详细信息

近几年对二连盆地、冀中坳陷岩性及地层油藏的勘探研究结果表明,与构造油藏相比,由于圈闭形成机制的不同和成藏控制因素的差异,岩性、地层油藏主要沿“湖泛面、不整合面、断面”分布;既可分布于低势区,也可分布于高势区;既可发育于低位域,也可发育于高位域。岩性油藏的分布主要受控于沉积体系,地层油藏的分布主要受控于削截带和超覆带,其富集程度主要受沉积储集相带的控制。因此,在对岩性及地层油藏的勘探中,一定要以沉积体系、地层超覆、地层剥蚀为主控因素重新划分勘探单元;注重对“湖泛面、不整合面、断面”控藏和沉积相、储集相的研究;要拓展勘探领域,即由环洼向洼槽,由正向构造区向负向构造区,由构造带的高部位向构造带的翼部,由构造带向岩相带、超覆带、剥蚀带延伸。

关键词：岩性油藏地层油藏分布特征湖泛面不整合面冀中坳陷二连盆地

Dynamic event-triggered data-driven iterative learning bipartite tracking control for nonlinear MASs with prescribed performance

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Science China(Information Sciences) 2025年第1期68卷 292-305页

作者： Tao shi wei-wei CHE School of Mechatronic Engineering and Automation Shanghai University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University College of Information Science and Engineering Northeastern University

This article proposes a distributed dynamic event-triggered data-driven iterative learning control(DET-DDILC)scheme under a predefined performance to tackle the bipartite tracking control problem for multiagent systems(MASs). An improved dynamic linearization technique is utilized to convert the nonlinear MASs into an iterative linear data model. First,a peer-to-peer mapping function is introduced to map the constrained distributed system output homeomorphism to an unconstrained one. In addition, a DET mechanism based on a time-iteration-varying function is devised to conserve network communication resources. Based on the unconstrained transformation and the designed DET mechanism, the DET-DDILC algorithm is devised to ensure that the bipartite tracking performance of MASs can be within the preset range. Finally, the effectiveness and feasibility of the designed control scheme are demonstrated via a simulation case by a comparison.

关键词： bipartite tracking control prescribed performance event-triggered iterative learning control multiagent systems

Soft Fault Diagnosis of Analog Circuit Based on Particle Swarm Optimization

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Journal of Electronic Science and Technology of China 2009年第4期7卷 358-361页

作者： Long-Fu Zhou yi-Bing shi wei Zhang School of Automation Engineering University of Electronic Science and Technology of China Chengdu 611731 China

A single soft fault diagnosis method for analog circuit with tolerance based on particle swarm optimization （PSO） is proposed. The parameter deviation of circuit elements is defined as the element of particle. Node-voltage incremental equations based on the sensitivity analysis are built as constraints of a linear programming （LP） equation. Through inducing the penalty coefficient, the LP equation is set as the fitness function for the PSO program. After evaluating the best position of particles, the position of the optimal particle states whether the actual parameter is within tolerance range or not. Simulation result shows the effectiveness of the method.

关键词： Analog circuit diagnosis linear program particle swarm optimization soft fault.

Evaluation of surgical strategy for low anterior resection syndrome using preoperative low anterior resection syndrome score in China

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World Journal of Gastrointestinal Surgery 2025年第1期17卷 175-183页

作者： Yang-Tao Pan yi-Min Lv shi-Chao Zhou Dan-Yan Luo Hao Sun wei-Feng Lao wei Zhou Department of Colorectal Surgery Sir Run Shaw Hospital Affiliated with Zhejiang UniversityHangzhou 310016Zhejiang ProvinceChina School of Mathematics Nanjing Audit UniversityNanjing 211815Jiangsu ProvinceChina Department of Surgery Zhejiang Hospital of Traditional Chinese Medicine(Zhejiang University of Traditional Chinese Medicine First Affiliated Hospital)Hangzhou 310000Zhejiang ProvinceChina NBU Health Science Center Ningbo UniversityNingbo 315000Zhejiang ProvinceChina

BACKGROUND Despite improved survival rates in rectal cancer treatment,many patients experience low anterior resection syndrome(LARS).The preoperative LARS score(POLARS)aims to address the limitations of LARS assessment by predicting outcomes preoperatively to enhance surgical *** To investigate the predictive accuracy of POLARS in assessing the occurrence of *** This study enrolled a total of 335 patients who underwent laparoscopic or robotic low anal sphincter-preserving surgery for rectal *** were categorized into three groups according to their POLARS score:no LARS(score 0-20),minor LARS(score 21-29),and major LARS(score 30-42).The QLQ-C30/CR29 scores were compared among these groups,and the agreement between POLARS predictions and the actual LARS scores was *** The study population was divided into three groups:major LARS(n=51,27.42%),minor LARS(n=109,58.6%),and no LARS(n=26,13.98%).Significant differences in the QLQ-C30 scales of social function,diarrhea,and financial impact were detected between the no LARS and major LARS groups(P<0.05)and between the minor LARS and major LARS groups(P<0.05).Similarly,significant differences were detected in the QLQ-CR29 scales for blood and mucus in the stool,fecal incontinence,and stool frequency between the no LARS and minor LARS groups(P<0.05),as well as between the minor LARS and major LARS groups(P<0.05).The predictive precision for major LARS using the POLARS score was 82.35%(42/51),with a recall of 35.89%(42/117).The mean absolute error(MAE)between the POLARS score and the actual LARS score was 8.92±*** contrast,the XGBoost(extreme gradient boosting)model achieved a lower MAE of 6.29±4.77,with a precision of 84.39%and a recall of 74.05%for predicting major *** The POLARS score demonstrated effectiveness and precision in predicting major LARS,thereby providing valuable insights into postoperative symptoms and patient quality of ***,the XGBoost model exh

关键词： Low anterior resection syndrome Preoperative assessment Predictive Accuracy Quality of life Machine learning

Purtscher-like retinopathy associated with COVID-19:a case report

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 187-189页

作者： Wen-Bo Liu yi Cai Miao Zhou Hashimoto Kinji Ming-wei Zhao Xuan shi Department of Ophthalmology Peking University People’s Hospital/Eye Disease and Optometry InstituteBeijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid DiseasesCollege of OptometryPeking University Health Science CenterBeijing 100044China

Dear Editor,We report a case of Purtscher-like retinopathy in a patient with coronavirus disease 2019(COVID-19).Fundus examination revealed extensive peripapillary white retinal patches(Purtscher’s fleckens)and cotton-wool spots(CWS)with minor hemorrhage bilaterally,consistent with Purtscher-like *** coherence tomography angiography(OCTA)showed multiple irregular areas of capillary nonperfusion.

关键词： Purtscher retinopathy capillary

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan shi Qun yi Yao Liu yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationHubei Key Laboratory of Novel Reactor and Green Chemical TechnologySchool of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan 430205HubeiChina Key Laboratory of Pesticide&Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079HubeiChina College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108FujianChina

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction(OER).Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER ***,most of them undergo incomplete reconstruction with limited thickness of reconstruction layer,leading to low component utilization and arduous exploration of real catalytic ***,we identify the dynamic behaviors in complete reconstruction of Co-based complexes during *** hollow phytic acid(PA)cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability,in favor of the fast and complete reconstruction.A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co(Fe)(OH)xand subsequent potential-driven oxidation to Co(Fe)*** obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm^(-2)and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER *** work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Complete reconstruction Co-based complex Precatalysts Oxygen evolution reaction