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An Improved Aluminum Surface Defect Detection Algorithm Based on YOLOv8n
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作者 Hao Qiu Shoudong Ni 《Computers, Materials & Continua》 2025年第8期2677-2697,共21页
In response to themissed and false detections that are easily caused by the large variety of and significant differences among aluminum surface defects,a detection algorithm based on an improved You Only Look Once(YOL... In response to themissed and false detections that are easily caused by the large variety of and significant differences among aluminum surface defects,a detection algorithm based on an improved You Only Look Once(YOLO)v8n network is proposed.First,a C2f_DWR_DRB module is constructed by introducing a dilation-wise residual(DWR)module and a dilated reparameterization block(DRB)to replace the C2f module at the high level of the backbone network,enriching the gradient flow information and increasing the effective receptive field(ERF).Second,an efficient local attention(ELA)mechanism is fused with the high-level screening-feature pyramid networks(HS-FPN)module,and an ELA_HSFPN is designed to replace the original feature fusion module,enhancing the ability of the network to cope with multiscale detection tasks.Moreover,a lightweight shared convolutional detection head(SCDH)is introduced to reduce the number of parameters and the computational complexity of the module while enhancing the performance and generalizability of the model.Finally,the soft intersection over union(SIoU)replaces the original loss function to improve the convergence speed and prediction accuracy of the model.Experimental results show that compared with that of the original YOLOv8n model,the mAP@0.5 of the improved algorithm is increased by 5.1%,the number of parameters and computational complexity are reduced by 33.3%and 32.1%,respectively,and the FPS is increased by 4.9%.Compared with other mainstream object detection algorithms,the improved algorithm still leads in terms of core indicators and has good generalizability for surface defects encountered in other industrial scenarios. 展开更多
关键词 Aluminum surface defects YOLOv8n object detection attention mechanism
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LT-YOLO:A Lightweight Network for Detecting Tomato Leaf Diseases 被引量:1
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作者 Zhenyang He Mengjun Tong 《Computers, Materials & Continua》 2025年第3期4301-4317,共17页
Tomato plant diseases often first manifest on the leaves,making the detection of tomato leaf diseases particularly crucial for the tomato cultivation industry.However,conventional deep learning models face challenges ... Tomato plant diseases often first manifest on the leaves,making the detection of tomato leaf diseases particularly crucial for the tomato cultivation industry.However,conventional deep learning models face challenges such as large model sizes and slow detection speeds when deployed on resource-constrained platforms and agricultural machinery.This paper proposes a lightweight model for detecting tomato leaf diseases,named LT-YOLO,based on the YOLOv8n architecture.First,we enhance the C2f module into a RepViT Block(RVB)with decoupled token and channel mixers to reduce the cost of feature extraction.Next,we incorporate a novel Efficient Multi-Scale Attention(EMA)mechanism in the deeper layers of the backbone to improve detection of critical disease features.Additionally,we design a lightweight detection head,LT-Detect,using Partial Convolution(PConv)to significantly reduce the classification and localization costs during detection.Finally,we introduce a Receptive Field Block(RFB)in the shallow layers of the backbone to expand the model’s receptive field,enabling effective detection of diseases at various scales.The improved model reduces the number of parameters by 43%and the computational load by 50%.Additionally,it achieves a mean Average Precision(mAP)of 90.9%on a publicly available dataset containing 3641 images of tomato leaf diseases,with only a 0.7%decrease compared to the baseline model.This demonstrates that the model maintains excellent accuracy while being lightweight,making it suitable for rapid detection of tomato leaf diseases. 展开更多
关键词 YOLOv8n target detection LIGHTWEIGHT TOmATO attention mechanism
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Adsorption and visual detection of nitro explosives by pillar[n]arenes-based host–vip interactions
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作者 Xueru Zhao Aopu Wang +3 位作者 Shimin Wang Zhijie Song Li Ma Li Shao 《Chinese Chemical Letters》 2025年第4期211-215,共5页
Aromatic nitro compounds present substantial health and environmental concerns due to their toxic nature and potential explosive properties.Consequently,the development of host–vip molecular recognition systems for... Aromatic nitro compounds present substantial health and environmental concerns due to their toxic nature and potential explosive properties.Consequently,the development of host–vip molecular recognition systems for these compounds serves a dual-purpose:enabling the fabrication of high-performance sensors for detection and guiding the design of efficient adsorbents for environmental remediation.This study investigated the host–vip recognition behavior of perethylated pillar[n]arenes toward two aromatic nitro molecules,1-chloro-2,4-dinitrobenzene and picric acid.Various techniques including^(1)H NMR,2D NOESY NMR,and UV-vis spectroscopy were employed to explore the binding behavior between pillararenes and aromatic nitro vips in solution.Moreover,valuable single crystal structures were obtained to elucidate the distinct solid-state assembly behaviors of these vips with different pillararenes.The assembled solid-state supramolecular structures observed encompassed a 1:1 host–vip inclusion complex,an external binding complex,and an exo-wall tessellation complex.Furthermore,based on the findings from these systems,a pillararene-based test paper was developed for efficient picric acid detection,and the removal of picric acid from solution was also achieved using pillararenes powder.This research provides novel insights into the development of diverse host–vip systems toward hazardous compounds,offering potential applications in environmental protection and explosive detection domains. 展开更多
关键词 Pillar[n]arenes Host–vip interactions Aromatic nitro compounds Adsorptive separation Explosive detection
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A Real-Time Small Target Vehicle Detection Algorithm with an Improved YOLOv5m Network Model 被引量:3
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作者 Yaoyao Du Xiangkui Jiang 《Computers, Materials & Continua》 SCIE EI 2024年第1期303-327,共25页
To address the challenges of high complexity,poor real-time performance,and low detection rates for small target vehicles in existing vehicle object detection algorithms,this paper proposes a real-time lightweight arc... To address the challenges of high complexity,poor real-time performance,and low detection rates for small target vehicles in existing vehicle object detection algorithms,this paper proposes a real-time lightweight architecture based on You Only Look Once(YOLO)v5m.Firstly,a lightweight upsampling operator called Content-Aware Reassembly of Features(CARAFE)is introduced in the feature fusion layer of the network to maximize the extraction of deep-level features for small target vehicles,reducing the missed detection rate and false detection rate.Secondly,a new prediction layer for tiny targets is added,and the feature fusion network is redesigned to enhance the detection capability for small targets.Finally,this paper applies L1 regularization to train the improved network,followed by pruning and fine-tuning operations to remove redundant channels,reducing computational and parameter complexity and enhancing the detection efficiency of the network.Training is conducted on the VisDrone2019-DET dataset.The experimental results show that the proposed algorithmreduces parameters and computation by 63.8% and 65.8%,respectively.The average detection accuracy improves by 5.15%,and the detection speed reaches 47 images per second,satisfying real-time requirements.Compared with existing approaches,including YOLOv5m and classical vehicle detection algorithms,our method achieves higher accuracy and faster speed for real-time detection of small target vehicles in edge computing. 展开更多
关键词 Vehicle detection YOLOv5m small target channel pruning CARAFE
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An Improved YOLO Detection Approach for Pinpointing Cucumber Diseases and Pests
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作者 Ji-Yuan Ding Wang-Su Jeon +1 位作者 Sang-Yong Rhee Chang-Man Zou 《Computers, Materials & Continua》 SCIE EI 2024年第12期3989-4014,共26页
In complex agricultural environments,cucumber disease identification is confronted with challenges like symptom diversity,environmental interference,and poor detection accuracy.This paper presents the DM-YOLO model,wh... In complex agricultural environments,cucumber disease identification is confronted with challenges like symptom diversity,environmental interference,and poor detection accuracy.This paper presents the DM-YOLO model,which is an enhanced version of the YOLOv8 framework designed to enhance detection accuracy for cucumber diseases.Traditional detection models have a tough time identifying small-scale and overlapping symptoms,especially when critical features are obscured by lighting variations,occlusion,and background noise.The proposed DM-YOLO model combines three innovative modules to enhance detection performance in a collective way.First,the MultiCat module employs a multi-scale feature processing strategy with adaptive pooling,which decomposes input features into large,medium,and small scales.This approach ensures that high-level features are extracted and fused effectively,effectively improving the detection of smaller and complex patterns that are often missed by traditional methods.Second,the ADC2f module incorporates an attention mechanism and deep separable convolution,which allows the model to focus on the most relevant regions of the input features while reducing computational load.The identification and localization of diseases like downy mildew and powdery mildew can be enhanced by this combination in conditions of lighting changes and occlusion.Finally,the C2fe module introduces a Global Context Block that uses attention mechanisms to emphasize essential regions while suppressing those that are not relevant.This design enables the model to capture more contextual information,which improves detection performance in complex backgrounds and small-object scenarios.A custom cucumber disease dataset and the PlantDoc dataset were used for thorough evaluations.Experimental results showed that DM-YOLO achieved a mean Average Precision(mAP50)improvement of 1.2%p on the custom dataset and 3.2%p on the PlantDoc dataset over the baseline YOLOv8.These results highlight the model’s enhanced ability to detect small-scale and overlapping disease symptoms,demonstrating its effectiveness and robustness in diverse agricultural monitoring environments.Compared to the original algorithm,the improved model shows significant progress and demonstrates strong competitiveness when compared to other advanced object detection models. 展开更多
关键词 ADC2f C2fe cucumber diseases YOLOv8n multiCat pest detection
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Establishment of High-sensitivity Rapid Fluorescence Quantitative Detection Method for Antibody against Peste des Petits Ruminants Virus
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作者 Zhao LIU Bo LIU +3 位作者 Zhida LIN Hang SUN Yu SUN Xiaohui SONG 《Agricultural Biotechnology》 2024年第5期22-27,共6页
[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were ... [Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E.coli.Furthermore,based on the purified soluble N protein and NH fusion protein,a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established.[Results]The method could quickly and quantitatively detect PPR V antibody in sheep serum,with high sensitivity and specificity,without any cross reaction to other related sheep pathogens.The intra-batch and inter-batch coefficients of variation were less than 10%and 15%,respectively,and the method had good repeatability.Through detection on 292 clinical serum samples,it was compared with the French IDVET competitive ELISA kit,and the coincidence rate of the two methods reached 93.84%.Compared with the serum neutralization test,the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum(provided by the WOAH Brucellosis Reference Laboratory of France).[Conclusions]This method can realize rapid quantitative detection of PPR V antibody on site,and has high practical value and popularization value. 展开更多
关键词 Peste des Petits Ruminants n protein nH fusion protein Soluble expression and purification Rapid quantitative detection
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基于FTO调控Notch1通路观察阳和平喘颗粒对哮喘BMSC归巢的影响
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作者 王坤 方昊翔 曹晓梅 《细胞与分子免疫学杂志》 北大核心 2025年第7期585-592,共8页
目的观察N^(6)甲基腺嘌呤(m^(6)A)甲基化调控缺刻基因1(Notch1)通路对哮喘骨髓间充质干细胞(BMSC)归巢的影响,以及中药复方阳和平喘颗粒干预研究。方法采用大鼠BMSC和支气管上皮细胞共培养的方式。将提取的细胞分为支气管上皮细胞组、... 目的观察N^(6)甲基腺嘌呤(m^(6)A)甲基化调控缺刻基因1(Notch1)通路对哮喘骨髓间充质干细胞(BMSC)归巢的影响,以及中药复方阳和平喘颗粒干预研究。方法采用大鼠BMSC和支气管上皮细胞共培养的方式。将提取的细胞分为支气管上皮细胞组、哮喘支气管上皮细胞联合间充质干细胞共培养组(以下简称共培养组)、共培养细胞联合正常血清组、共培养细胞联合最佳含药血清组、siRNA-FTO联合正常血清组、siRNA-FTO-NC联合正常血清组、siRNA-FTO联合最佳含药血清组。检测共培养细胞活力和细胞周期变化;免疫荧光染色法检测BMSC归巢水平和归巢标志物;实时定量PCR检测Notch1通路相关基因的表达;Western blot法检测Notch1通路相关蛋白的表达。结果与支气管上皮细胞组比较,共培养细胞组BMSC归巢水平和趋化因子受体4(CXCR4)、人基质细胞衍生因子1(SDF-1)、Notch1、重组信号结合蛋白J(RBP-J)、发状分裂相关增强子1(Hes1)蛋白表达升高。与共培养细胞组、共培养细胞联合正常血清组比较,共培养细胞联合最佳含药血清组BMSC归巢水平及CXCR4、SDF-1表达升高,Notch1、Hes1蛋白mRNA表达降低。与siRNA-FTO-NC联合正常血清组比较,siRNA-FTO联合正常血清组Notch1、Activated Notch1、RBP-J、Hes1蛋白表达和细胞活力升高,BMSC归巢水平降低。与siRNA-FTO联合正常血清组比较,siRNA-FTO联合最佳含药血清组Notch1、RBP-J mRNA,Activated Notch1、Hes1蛋白表达降低,BMSC归巢水平升高,共培养细胞联合最佳含药血清组Notch1、RBP-J、Hes1 mRNA表达降低。与siRNA-FTO联合最佳含药血清组比较,共培养细胞联合最佳含药血清组细胞活力及Notch1、Activated Notch1、RBP-J、Hes1蛋白降低,BMSC归巢水平升高。结论阳和平喘颗粒可能通过上调FTO表达,抑制下游Notch1信号通路表达,从而促进哮喘BMSC归巢,减轻哮喘炎症。 展开更多
关键词 骨髓间充质干细胞(BmSC) 支气管哮喘 n^(6)甲基腺嘌呤(m^(6)A) notch1信号通路
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基于可变服务率M/M/c/N部分可修排队模型的银行服务窗口数优化设计
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作者 赵佳宜 李建军 刘力维 《应用数学》 北大核心 2025年第3期796-805,共10页
本文提出一种带有可变服务率的M/M/c/N排队模型,用于对银行服务系统进行建模,该模型考虑了顾客的不耐烦行为及部分服务台的不可靠性.用马尔可夫过程理论建立了系统稳态平衡方程,运用矩阵几何解方法对其求解,获得了系统的平均队长、顾客... 本文提出一种带有可变服务率的M/M/c/N排队模型,用于对银行服务系统进行建模,该模型考虑了顾客的不耐烦行为及部分服务台的不可靠性.用马尔可夫过程理论建立了系统稳态平衡方程,运用矩阵几何解方法对其求解,获得了系统的平均队长、顾客的总损失率等稳态性能特征.基于系统稳态性能特征,建立了以银行效益最大为目标的优化模型,以此来确定银行的最佳窗口数,并通过数字算例对优化模型进行了说明.本文的研究为银行提升服务质量和资源优化配置提供了一定的理论参考. 展开更多
关键词 可变服务率 m/m/c/n 不耐烦行为 不可靠性
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宫颈癌TNM分期与预后相关性分析 被引量:1
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作者 陈锦元 蒋祎 《世界肿瘤研究》 2025年第1期45-51,共7页
目的:基于SEER数据库的宫颈癌患者影响因素分析,分析影响宫颈癌预后的相关因素,为宫颈癌患者预后恢复及治疗提供科学参考依据。方法:利用SEER数据库初步筛查宫颈癌相关数据,从中下载所有符合研究的宫颈癌患者的不同病理分型的数据,选用... 目的:基于SEER数据库的宫颈癌患者影响因素分析,分析影响宫颈癌预后的相关因素,为宫颈癌患者预后恢复及治疗提供科学参考依据。方法:利用SEER数据库初步筛查宫颈癌相关数据,从中下载所有符合研究的宫颈癌患者的不同病理分型的数据,选用第八期T,N,M分期对数据的T,N,M分期进行整理,标准化,筛选,筛选条件为患者第八期T,N,M分期明确,有符合要求的观察结局,如死亡或存活。通过筛查出的患者的不同病理分型的数据,运用SPSS26.0统计软件进行统计描述,采用Kaplan-Meier法。描绘生存曲线并估计患者的生存率,死亡率。生存时间分布的组间比较采用Log-Rank检验,对分析结果中P α = 0.05,以P Objective: Study on the prognostic risk model of cervical cancer patients based on SEER database, analyze the relevant factors affecting the prognosis of cervical cancer, and provide scientific reference for the prognosis recovery and treatment of cervical cancer patients. Methods: The SEER database was used to preliminarily screen the data related to cervical cancer, download the data of different pathological types of cervical cancer patients in line with the study, and select the eighth stage T, N, M to sort out, standardize and screen the T, N and M stages of the data. The screening conditions were that the eighth stage T, N and M stages of patients were clear, and there were satisfactory observed outcomes, such as death or survival. Through the data of different pathological types of patients screened, spss26 0 statistical software for statistical description, using Kaplan Meier method. Draw the survival curve and estimate the survival rate and mortality of patients. The inter group comparison of survival time distribution adopts log rank test to conduct multi factor Cox analysis on the variables with statistical significance of P α = 0.05, P < 0.05. Result: (1) Kaplan Meier univariate analysis: different pathological stages of T stage, N stage and M stage have an impact on the survival of patients, which is statistically significant (P < 0.05), and can affect the survival of patients to varying degrees. (2) Cox multivariate analysis: T stage, N stage and M stage were independent prognostic factors affecting the survival time of patients. Conclusion: Different T, N and M pathological stages of different cervical cancer patients can affect the prognosis of cervical cancer patients to varying degrees. They have a significant impact on the mortality and survival rate of cervical cancer patients, and can provide relevant basis for the development and improvement of the treatment scheme of cervical cancer. 展开更多
关键词 SEER数据库 宫颈癌 T n m病理分期 预后 影响因素分析
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纳米贝氏体对GCr15轴承钢M/B_(n)复合组织和力学性能的影响
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作者 周丽娜 杨晓峰 +2 位作者 麻健鹏 魏英华 于兴福 《金属热处理》 北大核心 2025年第5期40-45,共6页
通过对GCr15轴承钢采用油淬和200℃等温盐淬热处理,获得马氏体(M)和不同纳米贝氏体(B_(n))含量的复合组织(M/B_(n))。采用扫描电镜、洛氏硬度计和冲击试验机对微观组织、硬度和冲击性能进行表征,以研究M/B_(n)复合组织中纳米贝氏体含量... 通过对GCr15轴承钢采用油淬和200℃等温盐淬热处理,获得马氏体(M)和不同纳米贝氏体(B_(n))含量的复合组织(M/B_(n))。采用扫描电镜、洛氏硬度计和冲击试验机对微观组织、硬度和冲击性能进行表征,以研究M/B_(n)复合组织中纳米贝氏体含量对GCr15轴承钢组织和性能的影响。结果表明,油淬GCr15轴承钢的组织主要由球状颗粒碳化物、回火马氏体和残留奥氏体组成;等温淬火后,轴承钢的组织主要由球状碳化物、回火马氏体、贝氏体、残留奥氏体和二次析出细小碳化物组成。随着纳米贝氏体含量的增加,GCr15钢的硬度逐渐降低。采用860℃奥氏体化,盐浴200℃保温2 h,再经200℃回火后,获得的M/B_(n)复合组织硬度与845℃奥氏体化,油淬后经155℃回火获得的马氏体组织的硬度相当。此时,具有M/B_(n)复合组织钢中纳米贝氏体含量为47%,硬度为61.5 HRC,全马氏体组织钢的硬度为61.1 HRC,M/B_(n)复合组织钢的冲击吸收能量为9.92 J,全马氏体组织钢的冲击吸收能量为7.67 J,具有M/B_(n)复合组织钢的冲击吸收能量提高了29.34%,表明在硬度相当的情况下,M/B_(n)复合组织具有更好的综合力学性能。 展开更多
关键词 GCR15轴承钢 纳米贝氏体 m/B_(n)复合组织 硬度 冲击性能
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N-detect测试的优化方案
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作者 王欣 李锦明 《微电子学与计算机》 2025年第4期131-137,共7页
未建模故障引发的芯片失效问题日益严重,创新性的N-detect(多重检测)故障模型应运而生,其显著提升了未建模故障的覆盖率。然而,N-detect的测试向量繁多,成本高昂。为克服这一挑战,引入嵌入式多重检测(Embedded-Multi-Detect,EMD)算法进... 未建模故障引发的芯片失效问题日益严重,创新性的N-detect(多重检测)故障模型应运而生,其显著提升了未建模故障的覆盖率。然而,N-detect的测试向量繁多,成本高昂。为克服这一挑战,引入嵌入式多重检测(Embedded-Multi-Detect,EMD)算法进行优化,该算法利用测试向量中的无关位进行额外检测,扩大了测试范围。优化结果表明,这一创新在不增加测试向量的前提下提高了覆盖率,实现了测试向量的高效利用,提高了测试向量效率。 展开更多
关键词 多重检测 嵌入式多重检测 可测试性设计
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gl(2,1)到模李超代数W(m,n,q)的权导子
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作者 关露萍 孙丽萍 刘文德 《东北师大学报(自然科学版)》 北大核心 2025年第2期12-16,共5页
在特征p>2的域上,基于一般线性李超代数gl(2,1)到Cartan型模李超代数W(m,n,q)零部的嵌入关系,W(m,n,q)在伴随表示的意义下可视为gl(2,1)模.通过对W(m,n,q)进行子模分解和权空间分解,计算出了gl(2,1)到W(m,n,q)的保权导子,并得到了一... 在特征p>2的域上,基于一般线性李超代数gl(2,1)到Cartan型模李超代数W(m,n,q)零部的嵌入关系,W(m,n,q)在伴随表示的意义下可视为gl(2,1)模.通过对W(m,n,q)进行子模分解和权空间分解,计算出了gl(2,1)到W(m,n,q)的保权导子,并得到了一阶上同调群. 展开更多
关键词 李超代数W(m n q) 导子 权导子
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在(p,N)-策略控制下耐烦服务员不中断多重休假M/G/1排队的最优控制策略
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作者 尹伶玉 唐应辉 旷欣宇 《控制与决策》 北大核心 2025年第7期2185-2193,共9页
研究在(p,N)-策略控制下耐烦服务员不中断多重休假M/G/1排队系统,其中每当系统变空时,服务员去进行一次不中断的休假,当服务员休假回来时,若系统中等待服务的顾客数大于等于事先设置的正整数阈值N(N≥1),则服务员立即开始服务直到系统... 研究在(p,N)-策略控制下耐烦服务员不中断多重休假M/G/1排队系统,其中每当系统变空时,服务员去进行一次不中断的休假,当服务员休假回来时,若系统中等待服务的顾客数大于等于事先设置的正整数阈值N(N≥1),则服务员立即开始服务直到系统再次空竭;若系统中有顾客但顾客数少于N个,则服务员以概率p(0≤p≤1)开始服务,以概率1-p不服务,处于通常的闲期,直到系统中的顾客数累积到N时才服务.通过系统稳态队长的随机分解定理得到系统稳态队长分布的概率母函数和平均队长表达式,同时应用Little公式得到任意顾客的平均等待时间表达式.然后建立系统的费用结构模型,利用更新报酬定理推得系统长期运行单位时间的期望成本费用函数.进一步,在没有平均等待时间和有平均等待时间约束下,通过数值实例分别讨论系统的优化控制问题,并确定使系统费用最小的一维最优控制策略N^(*)和当休假时间为T时的二维最优控制策略(N^(*),T^(*)). 展开更多
关键词 m/G/1排队 (p n)-策略 不中断多重休假 队长的随机分解 最优控制策略
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卟啉直接退火制备M-N-C催化剂与电催化氮气还原
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作者 李启龙 朱卫华 梁旭 《合成化学》 2025年第9期607-615,共9页
氨气是一种理想的能量载体,但传统伯恩-哈珀合成方法条件苛刻,催化剂价格昂贵。电催化氮气还原是一种重要的氮化学转化方法,有望解决氨合成过程中的能源浪费和环境问题。M-N-C型催化剂以其丰富的活性位点和极高的原子利用率被广泛应用... 氨气是一种理想的能量载体,但传统伯恩-哈珀合成方法条件苛刻,催化剂价格昂贵。电催化氮气还原是一种重要的氮化学转化方法,有望解决氨合成过程中的能源浪费和环境问题。M-N-C型催化剂以其丰富的活性位点和极高的原子利用率被广泛应用于此领域。本文以四苯基卟啉自由碱为关键前驱体,利用中温直接退火,并引入不同金属离子,得到多例全新M-N-C型催化剂,并利用SEM、XRD和XPS等手段对材料结构进行了详细表征。研究表明:在体系中引入Fe离子,退火温度为700℃时,表现出最优异的电化学催化性能,NH3产率为12.7μg/(mg·h),Faraday效率为37.5%,且在长时间电解和多次循环使用中表现出优异的电化学稳定性,优于目前报道的多数M-N-C型催化剂。 展开更多
关键词 卟啉 m-n-C催化剂 氮气还原 电化学催化 电化学稳定性
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具有(2m+1)次非线性项和时空变系数的广义(n+1)维薛定谔方程的相似变换和精确解
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作者 王岗伟 谭子轩 《物理学报》 北大核心 2025年第11期134-140,共7页
薛定谔型方程是一类十分重要的微分方程.高维及变系数薛定谔型方程的研究具有一定的价值和意义.本文利用相似变换推导了(n+1)维(2m+1)次变系数非线性薛定谔方程的一类新的孤子解,给出了系数之间满足的关系.并利用定态薛定谔方程的解,得... 薛定谔型方程是一类十分重要的微分方程.高维及变系数薛定谔型方程的研究具有一定的价值和意义.本文利用相似变换推导了(n+1)维(2m+1)次变系数非线性薛定谔方程的一类新的孤子解,给出了系数之间满足的关系.并利用定态薛定谔方程的解,得到了(n+1)维(2m+1)次变系数非线性薛定谔方程的明暗孤子解.最后,对于特殊的情况,给出了明暗孤立子解的图像,并系统分析了孤子解的空间结构和传播特性. 展开更多
关键词 (n+1)维(2m+1)次非线性薛定谔方程 相似变换 精确解
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Adenosine kinase and ADAL coordinate detoxification of modified adenosines to safeguard metabolism
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作者 Akiko Ogawa 《四川生理科学杂志》 2025年第8期1719-1719,共1页
RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RN... RNA contains diverse post-transcriptional modifications,and its catabolic breakdown yields numerous modified nucleosides requiring correct processing,but the mechanisms remain unknown.Here,we demonstrate that three RNA-derived modified adenosines,N6-methyladenosine(m6A),N6,N6-dimethyladenosine(m6,6A),and N6-isopentenyladenosine(i6A),are sequentially metabolized into inosine monophosphate(IMP)to mitigate their intrinsic cytotoxicity. 展开更多
关键词 adenosine kinase modified adenosines modified adenosinesn methyladenosine m n n dimethyladenosine m catabolic breakdown modified nucleosides DETOXIFICATIOn inosine monophosphate imp adal
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Vortex Mössbauer Effect as Nanoscale Probe of Chiral Structures
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作者 Yixin Li Youjing Wang +6 位作者 Kai Zhao Zhiguo Ma Yumiao Wang Yi Yang Xiangjin Kong Changbo Fu Yu-Gang Ma 《Chinese Physics Letters》 2025年第6期27-37,共11页
Chirality,a common phenomenon in nature,appears in structures ranging from galaxies and condensed matter to atomic nuclei.There is a persistent demand for new,high-precision methods to detect chiral structures,particu... Chirality,a common phenomenon in nature,appears in structures ranging from galaxies and condensed matter to atomic nuclei.There is a persistent demand for new,high-precision methods to detect chiral structures,particularly at the microscale.Here,we propose a novel method,vortex Mössbauer spectroscopy,for probing chiral structures.By leveraging the orbital angular momentum carried by vortex beams,this approach achieves high precision in detecting chiral structures at scales ranging from nanometers to hundreds of nanometers.Our simulation shows the ratio of characteristic lines in the Mössbauer spectra of ^(57)Fe under vortex beams exhibits differences of up to four orders of magnitude for atomic structures with different arrangements.Additionally,simulations reveal the response of ^(229m)Th chiral structures to vortex beams with opposite angular momenta differs by approximately 49-fold.These significant spectral variations indicate that this new vortex Mössbauer probe holds great potential for investigating the microscopic chiral structures and interactions of matter. 展开更多
关键词 condensed matter chiral structures m ssbauer spectroscopyfor atomic nucleithere vortex beamsthis orbital angular momentum detecting chiral structures vortex m ssbauer spectroscopy
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单克隆抗体N-糖谱超高效液相色谱RapiFlior-MS荧光检测方法的建立及其验证
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作者 张旭凡 王辉 《中国生物制品学杂志》 2025年第9期1086-1093,共8页
目的 建立定量检测单克隆抗体中N-糖谱分布的亲水相互作用超高效液相色谱(hydrophilic interaction ultrahigh performance liquid chromatography,HILIC-UPLC)RapiFlior-MS荧光检测法,并进行验证。方法 采用GlycoWorks RapiFluor-MS N... 目的 建立定量检测单克隆抗体中N-糖谱分布的亲水相互作用超高效液相色谱(hydrophilic interaction ultrahigh performance liquid chromatography,HILIC-UPLC)RapiFlior-MS荧光检测法,并进行验证。方法 采用GlycoWorks RapiFluor-MS N糖分析试剂盒,用N-糖苷酶(PNGase F)和衍生试剂对N糖链快速酶切释放,再对游离N糖进行标记衍生,最后经UPLC进行分离检测:激发波长265 nm,发射波长425 nm,进样量10μL,柱温60℃。按峰面积归一化法计算,各N糖型峰面积占所有峰面积之和的百分比即为该N糖的相对百分含量。对建立的方法进行系统适用性、专属性、线性及范围、定量限、精密度、准确度、溶液稳定性和耐用性验证。用建立的方法检测6批单克隆抗体的N-糖谱分布。结果 建立的方法系统适用性、专属性良好,抗体浓度在0.002~5.2 mg/mL范围内,糖型G0F标准曲线线性较好,R^(2)> 0.99;定量限为0.09%;中间精密度验证中,G0F的相对百分含量的相对标准偏差(relative standard deviation,RSD)为0.33%;准确度验证中,G0F、G1Fa、G1Fb、G2F各N糖型的回收率在90%~110%范围内;抗体原液在(5±3)℃放置48 h,各糖型相对百分含量的RSD均≤2.0%;对色谱柱批次、流动相pH、柱温、试剂盒批次均具有一定的耐用性。6批抗体原液中,G0F、G1Fa、G1Fb相对百分含量的RSD均<5.0%,G2F相对百分含量的RSD<10.0%,生产过程工艺稳定,批间一致性良好。结论 建立的GlycoWorksRapiFluor-MS N糖分析试剂盒检测抗体中N-糖谱分布的方法专属性强,系统适用性、精密度、准确度、耐用性、稳定性良好,可用于抗体研发及生产过程中N-糖谱的监测。 展开更多
关键词 单克隆抗体 n-糖谱 RapiFlior-mS荧光检测 超高效液相色谱
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在服务启动N-策略控制下具有检修策略和不同到达率的M/G/1排队分析
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作者 李丰芮 唐应辉 《运筹学学报(中英文)》 北大核心 2025年第2期113-127,共15页
本文以制造系统为背景,提出一个在服务启动N-策略控制下具有检修策略和不同到达率的M/G/1排队模型。首先运用更新过程理论、全概率分解技术和拉普拉斯变换,研究系统在任意时刻t队长的瞬态性质,得到了瞬态队长分布关于时间t的拉普拉斯变... 本文以制造系统为背景,提出一个在服务启动N-策略控制下具有检修策略和不同到达率的M/G/1排队模型。首先运用更新过程理论、全概率分解技术和拉普拉斯变换,研究系统在任意时刻t队长的瞬态性质,得到了瞬态队长分布关于时间t的拉普拉斯变换表达式。然后在瞬态分析的基础上,使用洛必达法则得到队长稳态分布的递推表达式。最后,在建立费用模型下,应用更新报酬定理,得到系统在长期运行下单位时间内的期望费用表达式,并通过数值实例讨论了系统启动服务的最优控制策略和最优检修策略。 展开更多
关键词 m/G/1排队 检修策略 服务启动n-策略 队长分布 最优策略
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Ménétrier disease:A clinical review
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作者 Ana R Barros Sara Monteiro Jorge Silva 《World Journal of Gastroenterology》 2025年第32期1-9,共9页
Ménétrier disease(MD)is a rare gastric disorder characterized by hypertrophy of the gastric mucosa,resulting in giant gastric folds,excessive mucus secretion,and significant protein loss.It is most common in... Ménétrier disease(MD)is a rare gastric disorder characterized by hypertrophy of the gastric mucosa,resulting in giant gastric folds,excessive mucus secretion,and significant protein loss.It is most common in middle-aged males,although cases have also been reported in children.This condition,also known as hyperplastic hypersecretory gastropathy,primarily affects the fundus and body of the stomach,leading to protein-losing gastropathy due to increased mucosal permeability.The exact pathogenesis of MD remains unclear;however,it has been linked to excessive transforming growth factor-alpha signaling via the epidermal growth factor receptor(EGFR),which promotes mucosal hyperplasia.Clinical manifestations include epigastric pain,nausea,vomiting,anorexia,weight loss,and peripheral edema due to protein-losing enteropathy.Diagnosis is based on clinical presentation,endoscopic findings,and histopathology revealing foveolar hyperplasia and glandular atrophy.Treatment options vary from symptomatic management with proton pump inhibitors and nutritional support to monoclonal antibodies targeting EGFR(e.g.,cetuximab)in severe cases.In refractory situations,gastrectomy may be required.This review highlights the current understanding,diagnostic approaches,and therapeutic strategies for MD. 展开更多
关键词 ménétrier disease Giant hypertrophic gastritis Hypoproteinemic hypertrophic gastropathy HYPOALBUmInEmIA Protein-losing enteropathy
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