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基于ATMADDPG算法的多水面无人航行器编队导航

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吉林大学学报(信息科学版) 2024年第4期42卷 588-599页

作者：王思琪关巍佟敏赵盛烨大连海事大学航海学院吉林大学通信设计院股份有限公司辽宁一辉科技集团股份公司先进技术研究院

为提高多无人船编队系统的导航能力，提出了一种基于注意力机制的多智能体深度确定性策略梯度(ATMADDPG:Attention Mechanism based Multi-Agent Deep Deterministic Policy Gradient)算法。该算法在训练阶段，通过大量试验训练出最佳... 详细信息

为提高多无人船编队系统的导航能力，提出了一种基于注意力机制的多智能体深度确定性策略梯度(ATMADDPG:Attention Mechanism based Multi-Agent Deep Deterministic Policy Gradient)算法。该算法在训练阶段，通过大量试验训练出最佳策略，并在实验阶段直接使用训练出的最佳策略得到最佳编队路径。仿真实验将4艘相同的“百川号”无人船作为实验对象。实验结果表明，基于ATMADDPG算法的队形保持策略能实现稳定的多无人船编队导航，并在一定程度上满足队形保持的要求。相较于多智能体深度确定性策略梯度(MADDPG:Multi-Agent Depth Deterministic Policy Gradient)算法，所提出的ATMADDPG算法在收敛速度、队形保持能力和对环境变化的适应性等方面表现出更优越的性能，综合导航效率可提高约80%,具有较大的应用潜力。

关键词：多无人船编队导航 MADDPG算法注意力机制深度强化学习

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仔猪湿热泄泻的证型分布与辨证论治

中兽医医药杂志 2024年第5期43卷 83-86页

作者：王思齐刘森张世栋中国农业科学院兰州畜牧与兽药研究所甘肃兰州730050

仔猪腹泻是最常见的胃肠道疾病之一,在湿热、饮水不洁或饲料污染等复杂环境下,仔猪肠道的致病菌大量繁殖导致发病,可造成巨大的经济损失,严重制约了生猪养殖业的发展。中兽医学称腹泻为泄泻,其发病率高、侵害性强。根据病因的不同,泄泻... 详细信息

仔猪腹泻是最常见的胃肠道疾病之一,在湿热、饮水不洁或饲料污染等复杂环境下,仔猪肠道的致病菌大量繁殖导致发病,可造成巨大的经济损失,严重制约了生猪养殖业的发展。中兽医学称腹泻为泄泻,其发病率高、侵害性强。根据病因的不同,泄泻可分为多种类型,其中常见且难以辨证的是湿热型泄泻。湿热泄泻是由湿邪和热邪侵入机体,郁结于脾,脏腑运化失常导致的泄泻。临床中,仔猪湿热泄泻的主要症状为尿短赤,粪便稀薄、有腥臭味,且粪便常黏附在仔猪的肛门及后肢上,体温升高,若不及时治疗,病猪会严重脱水、营养不良,甚至导致死亡。治疗时应以运脾化湿、清热燥湿为主要原则,而不同日龄阶段仔猪的气血与脏腑机能不同,患湿热泄泻时机体表现的证候也有差异。根据湿热泄泻表现出来的不同证候特征,可分为脾虚湿热型、气虚郁热型和脾胃失和型3种证型。本文从病因病机、证候特征、治疗原则、证型分布及辨证论治等方面详细总结了仔猪湿热泄泻的中兽医临床诊疗方案,为仔猪湿热泄泻的致病机理、防治措施及相关的药物研发提供参考。

关键词：仔猪湿热泄泻证型分布辨证论治

黄精渣水不溶性膳食纤维提取工艺优化及特性表征

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保鲜与加工 2024年第9期24卷 53-64页

作者：王鑫课净璇王亚斌王思琪万鹏马艳莉卞华陈志周河北农业大学食品科技学院河北保定071000 南阳理工学院张仲景国医国药学院河南南阳473000

以废弃的黄精渣为原料,采用超声辅助酶法提取黄精渣水不溶性膳食纤维(PIDF)。通过单因素及响应面试验对提取工艺进行优化,并对提取的PIDF理化特性、结构特性表征及功能特性进行探究。结果表明,PIDF最佳提取条件为:超声时间28 min,超声功... 详细信息

以废弃的黄精渣为原料,采用超声辅助酶法提取黄精渣水不溶性膳食纤维(PIDF)。通过单因素及响应面试验对提取工艺进行优化,并对提取的PIDF理化特性、结构特性表征及功能特性进行探究。结果表明,PIDF最佳提取条件为:超声时间28 min,超声功率230 W,料液比1∶24(g/mL),此时PIDF得率为86.88%±0.51%;最优提取工艺条件下所得的PIDF纤维素含量31.5%,半纤维素含量24.4%,木质素含量20.8%,持水力(12.47±0.31)g/g,持油力(8.03±0.24)g/g,膨胀力(8.03±0.19) mL/g,结合水力(7.80±0.51) g/g;PIDF葡萄糖吸附能力为(21 333±30.21)μmoL/g,总酚、总黄酮含量分别为(5.89±0.02) mg/g和(1.92±0.04) mg/g,抗氧化能力较佳;扫描电镜显示,PIDF表面为不规则片状,傅里叶变换红外光谱呈现明显的多糖特征吸收峰,X射线结果显示PIDF呈纤维素I晶型,符合膳食纤维结构。综上可知,黄精渣含有丰富的水不溶性膳食纤维,可作为良好的水不溶性膳食纤维的新型来源。研究结果为提高黄精副产物综合利用提供了理论依据。

关键词：黄精渣水不溶性膳食纤维工艺优化理化性质

Resilience assessment model for urban public transportation systems based on structure and function

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Journal of Safety Science and Resilience 2023年第4期4卷 380-388页

作者： Changkun Chen Fan He Rongfu Yu siqi wang Qile Dai Institute of Disaster Prevention Science and Safety Technology Central South UniversityChangshaHunan410075China

Urbanization and the increasing frequency of extreme climates affect the sustainability of urban public transportation systems,and improving resilience is one of the primary directions for sustainable *** scientifically assess the resilience of urban public transportation systems,a resilience assessment model based on structure and function is established in this *** model mathematically quantifies and simulates the structural and functional changes in public transportation systems under disruption scenarios and provides a comprehensive assessment of six abilities:1)structural resistance,2)structural recoverability,3)functional resistance,4)functional recoverability,5)passenger adaptability,and 6)management *** on the initial failure stations,this model can simulate the resilience of a public transportation system under various *** model is applied to assess the resilience of public transportation systems in a provincial capital city under an equipment failure *** results show that the impact of equipment failure on resilience varies according to the metro lines,and improvement strategies for functional recoverability and management adaptability are *** weaknesses in the resilience of urban public transportation systems can be identified using the proposed model,which helps provide strategies for improving the capacity to face perturbations.

关键词： Urban public transportation Resilience assessment Transportation network System function

胰腺影像组学对乙肝肝硬化患者肝源性糖尿病的预测价值

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临床医药实践 2024年第7期33卷 527-534页

作者：王司琪郭东强武志峰山西医科大学医学影像学院山西太原030001 山西白求恩医院山西医学科学院山西太原030032

目的:分析乙肝肝硬化患者胰腺CT平扫及双能量CT(DECT)增强扫描动静脉期影像组学特征,及其对肝源性糖尿病(HD)的预测价值。方法:回顾性分析乙肝肝硬化患者胰腺CT平扫及DECT增强扫描动静脉期图像资料,采用慧影科研平台“慧医慧影”提取影... 详细信息

目的:分析乙肝肝硬化患者胰腺CT平扫及双能量CT(DECT)增强扫描动静脉期影像组学特征,及其对肝源性糖尿病(HD)的预测价值。方法:回顾性分析乙肝肝硬化患者胰腺CT平扫及DECT增强扫描动静脉期图像资料,采用慧影科研平台“慧医慧影”提取影像组学特征,筛选出最优特征,收集患者肝功能分级(Child-Pugh分级)等多项临床数据,采用高斯朴素贝叶斯(Gaussian NB)、被动攻击型算法(PA)和支持向量机(SVM)三种机器学习分类算法,构建仅基于影像组学特征的模型(影像组学模型)和基于影像组学特征联合临床变量预测模型(联合模型),预测患者是否合并HD。采用受试者工作特征曲线下面积(AUC)等比较各算法构建的影像组学模型和联合模型的预测诊断效能。结果:肝炎肝硬化患者141例,经纳入和排除标准筛选后,共计134例患者纳入研究。依据临床诊断是否合并糖尿病分为HD组(49例)和nHD组(85例)。两组Child-Pugh分级比较,差异有统计学意义(P0.05)。与联合模型相比,影像组学模型预测效能较低。结论:基于CT平扫及DECT增强扫描动静脉期影像组学特征,联合肝功能分级等多项临床数据构建的机器学习网络模型,对乙肝肝硬化患者是否合并HD有一定的预测价值。

关键词：胰腺肝硬化影像组学双能量CT

多参数MRI影像组学评估浸润性乳腺癌HER⁃2表达状态的临床应用价值

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南京医科大学学报（自然科学版） 2024年第2期44卷 218-227页

作者：刘婷婷林佳璐娄鉴娟邹启桂王思奇蒋燕妮南京医科大学第一附属医院放射科江苏南京210029

目的:探讨基于多参数磁共振成像(magnetic resonance imaging,MRI)影像组学特征的模型预测浸润性乳腺癌人类表皮生长因子受体⁃2(human epidermal growth factor receptor⁃2,HER⁃2)表达状态的价值。方法:回顾性分析南京医科大学第一附属... 详细信息

目的:探讨基于多参数磁共振成像(magnetic resonance imaging,MRI)影像组学特征的模型预测浸润性乳腺癌人类表皮生长因子受体⁃2(human epidermal growth factor receptor⁃2,HER⁃2)表达状态的价值。方法:回顾性分析南京医科大学第一附属医院2018年1月—2019年12月401例乳腺癌患者的基线期MRI图像及临床资料。使用ITK⁃SNAP软件在快速反转恢复序列(turbo inversion recovery magnitude,TIRM)、动态对比增强磁共振成像第2期(dynamic⁃contrast enhanced magnetic resonance imaging phase 2,DCE2)、动态对比增强磁共振成像第4期(dynamic⁃contrast enhanced magnetic resonance imaging phase 4,DCE4)、弥散加权成像(diffusion⁃weighted imaging,DWI)和表观弥散系数(apparent diffusion coefficient,ADC)的最大肿瘤层面手动勾画二维感兴趣区域(region of interest,ROI),并对所勾画的ROI区域进行特征提取及降维筛选。应用逻辑回归(logistic re⁃gression,LR)算法建立预测HER⁃2表达状态的单参数模型、组合模型和多参数模型。结果:最终筛选出26个最优特征,其中按权重排序位居首位的特征为DCE2_original_shape_SurfaceVolumeRatio。单参数模型中预测效能最好的是DCE2模型,训练集及测试集的曲线下面积(area under curve,AUC)分别为0.907、0.879;组合模型中联合增强特征的模型比其他未联合增强特征的模型预测效能更好(P均≤0.001);多参数模型预测效能最佳(训练集及测试集的AUC值分别为0.932、0.906)。结论:基于多参数影像特征构建的影像组学模型评估浸润性乳腺癌HER⁃2表达状态有一定的临床价值,其中增强早期特征的预测价值较高。

关键词：乳腺癌影像组学 HER⁃2 磁共振成像异质性

Phylogeny and Biogeography of Common Toad(Bufo bufo) in Xinjiang, China

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Asian Herpetological Research 2021年第2期12卷 201-212页

作者： siqi wang Chunxia XU Jiaqi ZHANG Supen wang Xuan LIU Xuejiao YANG Yiming LI Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The common toad, Bufo bufo(Linnaeus, 1758), is widely distributed in Europe and parts of Africa. Previous studies of the genetic relationships among B. bufo populations have not included Asian populations. Here, we investigated the phylogenetic relationships of B. bufo, including a population from Xinjiang, China, using 722 bp of the mitochondrial cytochrome b sequence and identified six subclades and 85 haplotypes in populations from 22 countries. Phylogenetic analyses and pedigree differentiation revealed that the subclade containing the Xinjiang population has undergone a relatively recent expansion. Combining our results with those of previous studies, we found that the common toad population of Xinjiang, China, belongs to the European-Caucasian lineage and that its closest relatives based on phylogenetic relationships were eastern European populations. Our research contributes to expanding knowledge of the geographic distribution of B. bufo and illuminates the lineage and genetic relationships of the B. bu fo population in Xinjiang, China. Future research should continue to update the geographic distribution of B. bufo and complete a genetic investigation of the full range of this species.

关键词： distribution genetic distance genetic structure haplotype mitochondrial DNA phylogenetic tree

Stabilization of ion-temperature-gradient mode by trapped fast ions

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Plasma Science and Technology 2022年第6期24卷 105-115页

作者： siqi wang Huishan CAI Baofeng GAO Ding LI CAS Key Laboratory of Geospace Environment School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026People's Republic of China Institute of Physics Chinese Academy of SciencesBeijing 100190People's Republic of China

Understanding and modeling fast-ion stabilization of ion-temperature-gradient(ITG)driven microturbulence have profound implications for designing and optimizing future fusion *** this work,an analytic model is presented,which describes the effect of fast ions on ITG *** model is derived from a bounce-average gyro-kinetic equation for trapped fast ions and ballooning transformation for ITG *** addition to dilution,strong wave-fast-ion resonant interaction is involved in this *** on numerical calculations,the effects of the main physical parameters are *** increasing density of fast ions will strengthen the effects of fast *** effect of wave-particle resonance strongly depends on the temperature of fast ***,both increasing density gradient and the ratio of the temperature and density gradients can strengthen the stabilization of fast ions in ITG ***,the influence of resonance broadening of wave-particle interaction is discussed.

关键词： fast ions ITG instability gyro-kinetic

Microstructural Evolution and Anisotropic Weakening Mechanism of ZK60 Magnesium Alloy Processed by Isothermal Repetitive Upsetting Extrusion

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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 839-852页

作者： Zhengran Liu Xi Zhao Kai Chen siqi wang Xianwei Ren Zhimin Zhang Yong Xue School of Mechanical and Electrical Engineering North University of ChinaTaiyuan030051China Engineering Technology Research Center for Integrated Precision Forming of Shanxi Province North University of ChinaTaiyuan030051China

The isothermal repetitive upsetting extrusion(RUE)was implemented to process ZK60 magnesium alloy at 380℃.Then,the relationship between the microstructural characters,including grain refinement and texture evolution,and the mechanical performance of the alloy was *** showed that after 3 passes of RUE,the average grain size was refined from 115.0 to 26.5μm,which was mainly caused by the continuous dynamic recrystallization and discontinuous dynamic ***,the elongation of the alloy increased from 13.8 to 21.6%,and the superplasticity(142%)of the alloy has been achieved in the following high temperature tensile test,which is very beneficial for the further processing of the alloy into *** particular,the alloy formed a distinctive texture distributed betweenand,which was greatly related to the Schmid factor of extrusion direction(ED)and transverse direction(TD).This texture changed the initiation ability of basal and prismatic slip in both directions and inhibited the initiation of partial tensile twinning in TD;thus,the anisotropy in both directions was *** expected,the tensile yield strength difference decreased from25.9 to 3.4 MPa,but it was used as the cost of tensile yield strength in ED.

关键词： Severe plastic deformation Repetitive upsetting extrusion ZK60 alloy Microstructure Mechanical properties