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PRNet:渐进式消减不确定区域的息肉分割网络

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湖南大学学报（自然科学版） 2024年第6期51卷 40-51页

作者：何东之肖杏梅李韫昱薛永乐李雲奇北京工业大学信息学部北京100124 中国人民解放军第一医学中心北京100039

由于息肉图像的自动分割病灶区域大小不一和边界模糊,从而导致分割精度较低.针对这两个问题,本文提出先定位后逐步精细的渐进式消减网络(Progressive Reduction Network,PRNet).该网络采用Res2Net提取病灶区域特征,利用多尺度跨级融合... 详细信息

由于息肉图像的自动分割病灶区域大小不一和边界模糊,从而导致分割精度较低.针对这两个问题,本文提出先定位后逐步精细的渐进式消减网络(Progressive Reduction Network,PRNet).该网络采用Res2Net提取病灶区域特征,利用多尺度跨级融合模块将注意融合机制与跨级特征结合,有效应对病灶区域多尺度问题,提升定位准确度.在自上而下恢复图像分辨率的过程中,引入不确定区域处理模块和多尺度上下文感知模块.前者通过设定递减的阈值逐步挖掘息肉边缘信息,增强边缘细节特征的识别能力;后者则进一步探索病灶区域周围潜在的上下文语义,提升模型的整体表征能力.此外,本算法还设计了一个简单的特征过滤模块,用于筛选编码器特征中的有效信息.在Kvasir-SEG、CVC-Clinic和ETIS数据集上的实验结果表明,所提算法的Dice系数分别达到了92.09%、93.05%和74.19%,优于现有的息肉分割算法,展示出了较好的鲁棒性和泛化性.

关键词：医学图像处理息肉分割结肠镜不确定区域多尺度

Strain Amplitude Effect on the Viscoelastic Mechanics of Chloroprene Rubber

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Acta Mechanica Solida Sinica 2020年第3期33卷 392-402页

作者： Longfan Peng Zhida li yunyu li Institute of Transportation Wuhan University of TechnologyWuhan 430063HubeiChina

This paper establishes an empirical formula to predict the strain amplitude effect.A viscoelastic constitutive model-the superposition of a hyperelastic model and a viscoelastic model-is constructed based on the laws of *** Mooney Rivlin model and the Prony series are employed for uniaxial tension *** empirical formula is derived using a hysteresis loop;it obtains results that are in agreement with the experimental results of dynamic mechanical analysis(DMA).The empirical formula proposed in this paper has certain accuracy in predicting the dynamic modulus under different strain amplitudes.

关键词： Viscoelasticity Strain amplitude effect Storage modulus Loss modulus Hysteresis loop

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基于收益途径的有色金属采矿权评估方法

科技和产业 2024年第6期24卷 125-131页

作者：李云煜刘春学云南财经大学物流与管理工程学院昆明650000 云南财经大学研究生院昆明650000

通过对收益途径评估采矿权价值的三种方法进行阐述,比较其不同之处,并结合有色金属采矿权评估的特点,分析有色金属采矿权评估中不同情况下评估方法的选择,并说明有色金属价格剧烈波动,需要结合相应有色金属产业链传导机制并使用合适的... 详细信息

通过对收益途径评估采矿权价值的三种方法进行阐述,比较其不同之处,并结合有色金属采矿权评估的特点,分析有色金属采矿权评估中不同情况下评估方法的选择,并说明有色金属价格剧烈波动,需要结合相应有色金属产业链传导机制并使用合适的价格预测模型预测有色金属价格,同时根据不同矿种引入特有风险计算折现率。此外可以将有色金属开采过程中的碳排放成本内部化,更好地平衡环境保护和矿产资源开采之间的关系。

关键词：有色金属采矿权折现现金流量法剩余利润法收入权益法

A Novel Adaptive Kalman Filter Based on Credibility Measure

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IEEE/CAA Journal of Automatica Sinica 2023年第1期10卷 103-120页

作者： Quanbo Ge Xiaoming Hu yunyu li Hongli He Zihao Song IEEE the School of Automation Nanjing University of Information Science and TechnologyNanjing 210044 Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET) Nanjing University of Information Science&TechnologyNanjing 210044China KTH Royal Institute of Technology Stockholm 10044Sweden the School of Automation Hangzhou Dianzi UniversityHangzhou 310000China the Testing Institute Chinese Flight Test EstablishmentXi’an 710000China the School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang 330000China

It is quite often that the theoretic model used in the Kalman filtering may not be sufficiently accurate for practical applications,due to the fact that the covariances of noises are not exactly *** previous work reveals that in such scenario the filter calculated mean square errors(FMSE)and the true mean square errors(TMSE)become inconsistent,while FMSE and TMSE are consistent in the Kalman filter with accurate *** can lead to low credibility of state estimation regardless of using Kalman filters or adaptive Kalman ***,it is important to study the inconsistency issue since it is vital to understand the quantitative influence induced by the inaccurate *** at this,the concept of credibility is adopted to discuss the inconsistency problem in this *** order to formulate the degree of the credibility,a trust factor is constructed based on the FMSE and the ***,the trust factor can not be directly computed since the TMSE cannot be found for practical *** on the definition of trust factor,the estimation of the trust factor is successfully modified to online estimation of the *** importantly,a necessary and sufficient condition is found,which turns out to be the basis for better design of Kalman filters with high ***,beyond trust factor estimation with Sage-Husa technique(TFE-SHT),three novel trust factor estimation methods,which are directly numerical solving method(TFE-DNS),the particle swarm optimization method(PSO)and expectation maximization-particle swarm optimization method(EM-PSO)are *** analysis and simulation results both show that the proposed TFE-DNS is better than the TFE-SHT for the case of single unknown noise ***,the proposed EMPSO performs completely better than the EM and PSO on the estimation of the credibility degree and state when both noise covariances should be estimated online.

关键词： Credibility expectation maximization-particle swarm optimization method(EM-PSO) filter calculated mean square errors(MSE) inaccurate models Kalman filter Sage-Husa true MSE(TMSE)

考虑对称交互熵的对偶犹豫模糊企业环境行为决策模型分析

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运筹与管理 2024年第2期33卷 49-56页

作者：曲国华栗赟余曲卫华董丹琪叶佳蒙山西财经大学管理科学与工程学院山西太原030006 山西大学管理与决策研究所山西太原030006 山西大学经济与管理学院山西太原030006

顺应绿色新发展理念,建设高质量生态文明,提升企业环境治理能力现代化水平,企业环境行为指标已逐渐被纳入投资者考量范围。本文针对第三方国际环境审计平台对企业环境行为评价的问题,研究面向对偶犹豫模糊评价信息的聚类方法。首先,定... 详细信息

顺应绿色新发展理念,建设高质量生态文明,提升企业环境治理能力现代化水平,企业环境行为指标已逐渐被纳入投资者考量范围。本文针对第三方国际环境审计平台对企业环境行为评价的问题,研究面向对偶犹豫模糊评价信息的聚类方法。首先,定义对偶犹豫模糊相对熵与对称交互熵,并基于信息论角度提出一个新的对偶犹豫模糊相似度公式;然后,构造相似系数矩阵,并基于编网聚类方法对对偶犹豫模糊集进行聚类。最后,以不同指标权重下评价企业环境行为优劣程度为例进行计算,并与使用传统相关系数聚类方法所得结果进行对比,说明在考虑决策者提供的信息量较大的情况下,本文方法概念清晰、计算简单、分辨率高,是一种更加灵活、全面的多层次评价方法,为完善企业环境评价系统的构建提供了一种新思路。

关键词：企业环境行为对偶犹豫模糊集对称交互熵相似度聚类

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国际关于流域洪涝灾害风险研究知识图谱分析

中外建筑 2024年第8期 45-48页

作者：张鹏李云玉倪丽丽河北工业大学建筑与艺术设计学院

为清晰认知国际关于流域洪涝灾害风险的研究热点和研究过程,借助文献计量软件Citespace对2002—2023年Web of Science核心数据库中收录的与流域洪涝相关的文献进行可视化分析,并绘制流域洪涝灾害风险知识图谱,从国际关于流域洪涝灾害风... 详细信息

为清晰认知国际关于流域洪涝灾害风险的研究热点和研究过程,借助文献计量软件Citespace对2002—2023年Web of Science核心数据库中收录的与流域洪涝相关的文献进行可视化分析,并绘制流域洪涝灾害风险知识图谱,从国际关于流域洪涝灾害风险研究的文献数量、研究热点、时空演化路径、理论技术研究进展等几个方面进行分析,挖掘国际流域洪涝灾害风险的潜在内涵,以期为未来研究提供参考。

关键词：流域洪涝风险研究进展文献计量评述

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A Novel Multiscale Reinforcement by In-Situ Growing Carbon Nanotubes on Graphene Oxide Grafted Carbon Fibers and Its Reinforced Carbon/Carbon Composites with Improved Tensile Properties

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Journal of Materials Science & Technology 2016年第5期32卷 419-424页

作者： yunyu li ling-jun Guo Ya-wen Wang He-jun li Qiang Song State Key Laboratory of Solidification Processing Northwestern Polytechnical University Center for Nano Energy Materials Northwestern Polytechnical University

In-situ growing carbon nanotubes （CNTs） directly on carbon fibers （CFs） always lead to a degraded tensile strength of CFs and then a poor fiber-dominated mechanical property of carbon/carbon composites （C/ Cs）. To solve this issue, here, a novel carbon fiber-based multiscale reinforcement is reported. To synthesize it, carbon fibers （CFs） have been first grafted by graphene oxide （GO）, and then carbon nanotubes （CNTs） have been in-situ grown on GO-grafted CFs by catalytic chemical vapor deposition. Characterizations on this novel reinforcement show that GO grafting cannot only nondestructively improve the surface chemical activity of CFs but also protect CFs against the high-temperature corrosion of metal catalyst during CNT growth, which maintains their tensile properties. Tensile property tests for unidirectional C/Cs with different preforms show that this novel reinforcement can endow C/C with improved tensile properties, 32% and 87% higher than that of pure C/C and C/C only doped with in-situ grown CNTs. This work would open up a possibility to fabricate multiscale C/Cs with excellent global performance.

关键词： Multiscale reinforcement Carbon fiber Graphene oxide Carbon nanotube Carbon/carbon composite Tensile property

Optimal Operation Strategy Analysis with Scenario Generation Method Based on Principal Component Analysis,Density Canopy,and K-medoids for Integrated Energy Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 89-100页

作者： Bingtuan Gao yunyu Zhu Yuanmei li School of Electrical Engineering Southeast UniversityNanjingChina

The operation of integrated energy systems(IESs)is confronted with great challenges for increasing penetration rate of renewable energy and growing complexity of energy *** generation is one of ordinary methods to alleviate the system uncertainties by extracting several typical scenarios to represent the original high-dimensional *** paper proposes a novel representative scenario generation method based on the feature extraction of panel *** original high-dimensional data are represented by an aggregated indicator matrix using principal component analysis to preserve temporal ***,the aggregated indicator matrix is clustered by an algorithm combining density canopy and *** with the proposed scenario generation method,an optimal operation model of IES is established,where the objective is to minimize the annual operation costs considering carbon trading ***,case studies based on the data of Aachen,Germany in 2019 are *** results indicate that the adjusted rand index(ARI)and silhouette coefficient(SC)of the proposed method are 0.6153 and 0.6770,respectively,both higher than the traditional methods,namely K-medoids,K-means++,and density-based spatial clustering of applications with noise(DBSCAN),which means the proposed method has better *** error between optimal operation results of the IES obtained by the proposed method and all-year time series benchmark value is 0.1%,while the calculation time is reduced from 11029 s to 188 s,which verifies that the proposed method can be used to optimize operation strategy of IES with high efficiency without loss of accuracy.

关键词： Scenario generation principal component analysis(PCA) density canopy K-medoids integrated energy system

1株鸡腹泻源沙门氏菌的分离鉴定与耐药性分析

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黑龙江畜牧兽医 2024年第16期 68-77,118,119页

作者：顾宇华匡华丽伊雪燕殷鹤予何云凤李涵李蕴玉李佩国河北科技师范学院河北省预防兽医学重点实验室河北秦皇岛066604

为了明确河北省秦皇岛市某蛋鸡养殖场蛋鸡出现腹泻甚至死亡的原因,试验从采自该场的病死鸡肝脏和泄殖腔拭子样本中进行细菌的分离培养,并通过形态观察、革兰氏染色、特异性基因检测、16S rDNA基因的序列分析、血清分型及细菌多位点序列... 详细信息

为了明确河北省秦皇岛市某蛋鸡养殖场蛋鸡出现腹泻甚至死亡的原因,试验从采自该场的病死鸡肝脏和泄殖腔拭子样本中进行细菌的分离培养,并通过形态观察、革兰氏染色、特异性基因检测、16S rDNA基因的序列分析、血清分型及细菌多位点序列分型(multilocus sequence typing, MLST)对分离菌进行鉴定,通过致病性试验分析分离菌对雏鸡的致病性,采用PCR法分别对分离菌的毒力基因和耐药基因进行检测,分别采用K-B药敏纸片法和琼脂扩散法检测分离菌对10种抗生素和10味中草药的耐药性。结果表明:从病死鸡肝脏和泄殖腔拭子样本中分离并鉴定到1株鸡白痢沙门氏菌,命名为QHD 2023。分离菌QHD 2023株与鸡白痢沙门氏菌CP012347.1的亲缘关系最近,与肠炎沙门氏菌和鼠伤寒沙门氏菌亲缘关系较远;MLST序列型为ST92型。接种鸡白痢沙门氏菌QHD 2023株的雏鸡临床表现为被毛松乱、畏寒、扎堆、精神沉郁、排灰白色粪便,并伴有腹泻,剖检可见肝脏肿大明显、有灰白色坏死点或呈现铜绿色,与养殖场送检病死鸡肝脏病理变化表现一致,为沙门氏菌感染典型症状;7 d死亡率为60%。在分离菌中检出5种耐药基因(β-内酰胺类耐药基因bla CTX-M,四环素类耐药基因tet B、tet C、tet G及氯霉素类耐药基因cat A1)和17种毒力基因(spvA、spvB、spvC、spvD、spvR、sopE、sopB、sipA、sipC、 ssrA、sseL、 misL、mgtC、siiE、orf319、stnP1、sefA);分离菌QHD 2023株对环丙沙星、丁胺卡那、庆大霉素、卡那霉素、复方新诺明、头孢噻肟和头孢曲松共7种抗生素表现为敏感,对头孢氨苄表现为中介,对头孢拉定和多黏菌素B表现为耐药;对乌梅、黄芪和黄芩表现为敏感,对五味子表现为中介,对桔梗、苍术、黄柏、金银花、贯众和石榴皮共6味中草药表现为耐药。说明该场蛋鸡出现腹泻甚至死亡的原因为鸡白痢沙门氏菌感染,同时分离到1株具有致病性的鸡白痢沙门氏菌,该分离菌中含有多种耐药基因和毒力基因,除对7种抗生素敏感外,乌梅、黄芪、黄芩和五味子也均对其有一定的抑菌效果。

关键词：蛋鸡沙门氏菌毒力基因耐药基因中草药致病性试验