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基于特征增强和样本充分学习的红外飞机检测

电光与控制 2025年第1期32卷 54-60页

作者：徐红鹏刘刚司起峰陈会祥河南科技大学信息工程学院河南洛阳471000

针对深度学习单阶段检测算法对红外飞机目标的特征提取能力不足以及样本学习不充分的问题,提出基于特征增强的全局上下文机制(FEGCM)和样本充分学习的目标检测算法。FEGCM可获取包含目标的全局信息与局部信息的特征图,从而提高特征提取... 详细信息

针对深度学习单阶段检测算法对红外飞机目标的特征提取能力不足以及样本学习不充分的问题,提出基于特征增强的全局上下文机制(FEGCM)和样本充分学习的目标检测算法。FEGCM可获取包含目标的全局信息与局部信息的特征图,从而提高特征提取网络对目标特征的提取能力。通过在Focal Loss中添加调制因子,在关注难负样本学习的基础上,充分利用包含目标特性的部分易负样本,使得样本充分学习,从而帮助检测算法学习到更有意义的目标特征。实验表明,所提算法在自制红外飞机数据集上的mAP_(50)达到96.9%,能够有效实现红外飞机目标检测。

关键词：红外飞机检测全局上下文空间注意力 Focal Loss 易负样本

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Some Existence Theorems on All Fractional(g,f)-factors with Prescribed Properties

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Acta Mathematicae Applicatae sinica 2018年第2期34卷 344-350页

作者： si-zhong ZHOU Tao ZHANG School of Science Jiangsu University of Science and Technology Zhenjiang 212003 China School of Economic and Management Jiangsu University of Science and Technology Zhenjiang 212003 China

Let G be a graph, and g, f ： V（G）→Z＋ with g（x）〈 f（x） for each x ∈ V（G）. We say that G admits all fractional （g, f）-factors if G contains an fractional r-factor for every r ： V（G）→ Z＋ with g（x） ≤ r（x） ≤ f（x） for any x ∈ V（G）. Let H be a subgraph of G. We say that G has all fractional （g, f）-factors excluding H if for every r ： V（G） → Z＋ with g（x） ≤ r（x） ≤ f（x） for all x ∈ V（G）, G has a fractional r-factor Fh such that E（H） ∩ E（Fh） = Ф, where h ： E（G） → [0, 1] is a function. In this paper, we show a characterization for the existence of all fractional （g, f）-factors excluding H and obtain two sufficient conditions for a graph to have all fractional （g, f）-factors excluding H.

关键词： graph fractional (g, f)-factor all fractional (g, f)-factors.

成渝地区双城经济圈旅游共生水平测度及协同发展研究

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四川师范大学学报（自然科学版） 2025年第1期48卷 94-104页

作者：司嵬樊丹王冲四川旅游学院旅游文化产业学院四川成都610100 四川旅游学院大数据与统计学院四川成都610100 四川旅游学院文旅融合发展研究中心四川成都610100

基于共生理论和社会网络分析,从成渝地区旅游同质度、关联度、外向功能强度3个维度测评并分析成渝地区双城经济圈旅游业共生水平现状.通过分析得出:成渝地区双城经济圈旅游业的同质度和重合度均较高,成都市、重庆主城区、渝西毗邻片区3... 详细信息

基于共生理论和社会网络分析,从成渝地区旅游同质度、关联度、外向功能强度3个维度测评并分析成渝地区双城经济圈旅游业共生水平现状.通过分析得出:成渝地区双城经济圈旅游业的同质度和重合度均较高,成都市、重庆主城区、渝西毗邻片区3个片区处于成渝双城经济圈旅游共生的中心主导地位,成都是连接四川省其他地区和重庆片区的桥梁.广安市、达州市、资阳市与重庆地区虽联系较多,但是外向功能强度不高,还未发挥出旅游的带动和桥梁作用.成渝地区双城经济圈中旅游关系存在4个子群,重庆地区与川南地区子群具有较强的影响力,川东北与重庆毗邻地区是最具潜力子群.据此,从建立分工基础上的对称互惠一体化共生模式、营造良好的旅游市场一体化共生环境、打破行政区划创造多元旅游共生界面3个方面提出成渝地区双城经济圈旅游共生发展的对策建议.

关键词：成渝双城经济圈旅游共生社会网络分析区域协同

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多源固废协同制备土壤固化剂及固化机理

森林工程 2025年第1期41卷 195-204页

作者：褚锋吴思吴传山马亚李骏山东高速建设管理集团有限公司济南230000 山东高速济德公路有限公司山东德州253000 山东高速工程检测有限公司济南230002

为实现冶金固废材料的高值化、规模化利用,采用冶金固废材料(高炉矿渣、粉煤灰、电石渣、石膏)协同制备土壤固化剂,通过正交配比优化试验研究不同固废材料对固化土力学性能的影响并获取最优的参数配方。系统研究固废基固化剂(SWC)固化... 详细信息

为实现冶金固废材料的高值化、规模化利用,采用冶金固废材料(高炉矿渣、粉煤灰、电石渣、石膏)协同制备土壤固化剂,通过正交配比优化试验研究不同固废材料对固化土力学性能的影响并获取最优的参数配方。系统研究固废基固化剂(SWC)固化土的力学性能(无侧限抗压强度、劈裂强度、延迟成型)和耐候性能(水稳定性、冻融循环),并与PO 42.5硅酸盐水泥(OPC)进行对比。结果表明,电石渣对固化剂体系起到重要作用,合理的石膏掺量对强度增长有积极作用;固化土的强度随SWC掺量和养护龄期的增加而增大,4%掺量下的固化土7 d无侧限抗压强度大于1 MPa,劈裂强度与OPC固化土基本相当;SWC固化土表现出更久的施工容许延迟时间,拌和后12 h内强度无下降趋势;掺量大于5%时水稳定系数大于90%,同掺量下抗冻系数与水泥相比提高3%~5%,具备良好的水稳定性与抗冻性;X射线衍射(XRD)和扫描电子显微镜(SEM)分析表明,SWC固化土在水化过程中会生成膨胀性水化产物钙矾石(AFt)和硅酸钙(C-S-H),钙矾石晶体对改善固化土的劈裂强度和抵抗开裂变形能力提高作用显著。

关键词：道路工程固化剂力学性能固化土工业固废

The Biofunctions of Phytochemicals and Their Applications in Farm Animals： The Nrf2/Keap1 System as a Target

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Engineering 2017年第5期3卷 738-752页

作者： si Qin De-Xing Hou Key Laboratory for Food Science and Biotechnology of Hunan Province College of Food Science and Technology Hunan Agricultural University Changsha 410128 China Hun an Co-Innovation Center for Utilization of Botanical Functional Ingredients Hunan Agricultural University Changsha 410128 China The United Graduate School of Agricultural Sdences Faculty of Agriculture Kagoshima University Korimoto Kagoshima 890-0065 Japan

Reactive oxygen species （ROS） can be caused by mechanical, thermal, infectious, and chemical stimuli, and their negative effects on the health of humans and other animals are of considerable concern. The nuclear factor （erythroid-derived 2）-like 2/Kelch-like ECH-associated protein 1 （Nrf2/Keap1） system plays a major role in maintaining the balance between the production and elimination of ROS via the regulation of a series of detoxifying and antioxidant enzyme gene expressions by means of the antioxidant response element （ARE）. Dietary phytochemicals, which are generally found in vegetables, fruits, grains, and herbs, have been reported to have health benefits and to improve the growth performance and meat quality of farm animals through the regulation of Nrf2-mediated phase II enzymes in a variety of ways. However, the enormous quantity of somewhat chaotic data that is available on the effects of phytochemicals needs to be properly classified according to the functions or mechanisms of phytochemicals, in this review, we first introduce the antioxidant properties of phytochemicals and their relation to the Nrf2/Keap1 system. We then summarize the effects of phytochemicals on the growth performance, meat quality, and intestinal microbiota of farm animals via targeting the Nrf2/Keap1 system. These exhaustive data contribute to better illuminate the underlying biofunctional properties of phytochemicals in farm animals.

关键词： Phytochemical Biofunction Nrf2/Keap1 system Growth performance Meat quality Intestinal microbiota

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一种适应于直流微电网的全桥LLC变换器

现代电子技术 2025年第2期48卷 29-34页

作者：国梦珠陈思郑贞钰郭永玉三峡大学电气与新能源学院湖北宜昌443000

针对传统的光伏并网隔离型变换器的变压器体积大、损耗高和半导体器件电压应力高等问题,提出一种基于LLC谐振变换器的高增益DC-DC变换器。该变换器满足了输入输出之间电气隔离的要求,将全桥LLC谐振变换器与开关电容相结合,有效地提高了... 详细信息

针对传统的光伏并网隔离型变换器的变压器体积大、损耗高和半导体器件电压应力高等问题,提出一种基于LLC谐振变换器的高增益DC-DC变换器。该变换器满足了输入输出之间电气隔离的要求,将全桥LLC谐振变换器与开关电容相结合,有效地提高了变换器的增益,减少了变压器的体积和损耗,降低了半导体器件的电压应力,实现了开关管的零电压开通和二极管的零电流关断,有效地降低了开关损耗。首先对所提变换器的工作原理进行详细分析;其次用基波分析法分析其基本特性,并进行半导体器件电压、电流应力计算及电路的参数设计;最后搭建一台了800 W的实验样机,经过实验验证,该变换器实现了开关管的ZVS开通,二极管的ZCS关断;减小了变压器的体积和铜耗;转换效率最高可达94.9%。二次侧二极管的电压应力为输出电压的12,是全桥整流的0.5倍、半桥整流的0.25倍,且平均电流相同,有利于器件的选型,更适用于直流微电网的应用,证明了理论分析的准确性。

关键词：直流微电网 LLC谐振变换器 DC-DC变换器高增益电压应力开关电容基波分析法

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simulation of two-phase debris flow scouring bridge pier

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Journal of Mountain Science 2017年第11期14卷 2168-2181页

作者： LIU Wei HE si-ming Institute of Mountain Hazards and Environment (IMHE) Chinese Academy of Sciences Key laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences

Debris flows are typical two-phase flows, which commonly accompany erosion in mountainous areas, and may destroy bridge engineering by scouring. In this study, a physically-based two-phase model is applied for the simulation of debris flow scouring of bridge pier. In this model, the shear stress of debris flow on an erodible bed is considered to be a function of the solid shear stress, fluid shear stress, and volume fraction; accordingly, the erosion is incorporated into the two-phase model. Using a highaccuracy computational scheme based on the finite volume method, the model is employed for simulating a dynamic debris flow over an erodible bed. The numerical results are consistent with the experimental data, and verify the feasibility of the two-phase model. Moreover, a simple numerical test is performed to exhibit the fundamental behaviour of debris flow scouring of bridge pier, which shows that the degree of erosion on each side of the pier is higher compared to other areas. The scouring depth is influenced by the variations of solid volume fraction and velocity of debris flow and pier width.

关键词： Pier scouring Debris flow Two-phasemodel Numerical simulation

Development and evaluation of a herbal formulation with antipathogenic activities and probiotics stimulatory effects

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Journal of Integrative Agriculture 2016年第5期15卷 1103-1111页

作者： ZHOU Qian WANG si-si YANG Guang ZHAO Wen LI Hui-ling College of Food Science and Technology Agricultural University of Hebei Baoding 071001 P.R. China Engineering Technology Research Center for Agricultural Product Processing of Hebei Baoding 071001 P.R. China

Searching alternative feed antibiotics is always a study hotspot in the field of animal production. In this study, the antipathogenic activities and probiotics stimulatory effects of 30 kinds of herbs were screened through Oxford cup method and Hungate roll method. 15 herbs showed significantly antibacterial activities（P〈0.05） against Escherichia coli, Salmonella enteritidis, Salmonella typhimurium and Staphylococcus aureus. Seven herbs showed greatly stimulatory promoting effects on Lactobacillus acidophilus and Bifidobacterium longum. Finally, five herbs were combined for the developed formulation with selective antibacterial properties and they were Mume Fructus（35%）, Isatidis Folium（25%）, Moslae Herba（20%）, Chrysanthemi Indici Flos（13%） and Bupleuri Radix（7%）. The herbal formulation showed significantly antibacterial abilities against four pathogens and stimulatory promoting abilities on two probiotics in vitro and the equivalent activities in broiler chickens in vivo against E. coli and L. acidophilus. The toxicity study showed it had no toxicity, which indicated that it would be a kind of preferred candidate for an alternative antibiotic in future animal production.

关键词： herbal formulation alternative feed antibiotic anti-pathogenic activity probiotic stimulatory effect

A fast automatic recognition and location algorithm for fetal genital organs in ultrasound images

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第9期10卷 648-658页

作者： Sheng TANG si-ping CHEN Post-Doctoral Research Station Shenzhen University Shenzhen 518060 China post-Doctoral WorkStation Microprofit Electronie Co. Ltd Shenzhen 518057 China Department of Biomedical Engineering Shenzhen University Shenzhen 518060 China

Severe sex ratio imbalance at birth is now becoming an important issue in several Asian countries. Its leading immediate cause is prenatal sex-selective abortion following illegal sex identification by ultrasound scanning. In this paper, a fast automatic recognition and location algorithm for fetal genital organs is proposed as an effective method to help prevent ultrasound technicians from unethically and illegally identifying the sex of the fetus. This automatic recognition algorithm can be divided into two stages. In the 'rough' stage, a few pixels in the image, which are likely to represent the genital organs, are automatically chosen as points of interest (POIs) according to certain salient characteristics of fetal genital organs. In the 'fine' stage, a specifically supervised learning framework, which fuses an effective feature data preprocessing mechanism into the multiple classifier architecture, is applied to every POI. The basic classifiers in the framework are selected from three widely used classifiers: radial basis function network, backpropagation network, and support vector machine. The classification results of all the POIs are then synthesized to determine whether the fetal genital organ is present in the image, and to locate the genital organ within the positive image. Experiments were designed and carried out based on an image dataset comprising 658 positive images (images with fetal genital organs) and 500 negative images (images without fetal genital organs). The experimental results showed true positive (TP) and true negative (TN) results from 80.5% (265 from 329) and 83.0% (415 from 500) of samples, respectively. The average computation time was 453 ms per image.

关键词： Ultrasound image Fetal genital organ Point of interest (POI) Feature selection Feature extraction Class imbalance Multiple classifier architecture