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基于PSD特征的FBCCA脑电信号识别方法
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作者 张学军 杨京儒 《科学技术与工程》 北大核心 2024年第4期1411-1417,共7页
当前基于稳态视觉诱发电位(steady-state visual evoked potential,SSVEP)的脑机接口(brain-computer interfaces,BCIs)使用的都是单一识别算法,针对不同时间长度的识别准确率较低。提出了一种基于滤波器组的典型相关分析(filter bank c... 当前基于稳态视觉诱发电位(steady-state visual evoked potential,SSVEP)的脑机接口(brain-computer interfaces,BCIs)使用的都是单一识别算法,针对不同时间长度的识别准确率较低。提出了一种基于滤波器组的典型相关分析(filter bank canonical correlation analysis,FBCCA)与功率谱密度(power spectral density,PSD)分析相结合的SSVEP识别算法,可以提高SSVEP识别的普适性与准确率。该方法使用FBCCA寻找高相似度的参考频率信号,再通过多组PSD分析来锁定最终的响应频率,完成频率识别。该方法无需经过训练就能得到较高的识别准确率。实验结果表明:在刺激时长为1 s时,该方法能达到86.61%的准确率,比PSD分析方法提升了5.44%,比典型相关性分析方法(canonical correlation analysis,CCA)提升了10.38%的准确率,比FBCCA提升了8.86%的准确率。 展开更多
关键词 脑机接口(BCI) 稳态视觉诱发电位(SSVEP) 滤波器组的典型相关分析(FBCCA) 功率谱密度(psd) 频率识别
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基于PSD传感器的炸点三维坐标测量方法研究
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作者 宁威 褚文博 +1 位作者 张斌 赵冬娥 《计算机测量与控制》 2024年第3期195-203,共9页
针对野外炸点空间三维坐标测量的问题,提出了基于二维PSD位置传感器的炸点位置测量方法,构建了基于二维PSD位置传感器的炸点三维坐标测量系统;基于双目视觉原理建立了炸点空间三维坐标测量数学模型;研究了被动探测系统在野外远距离下的... 针对野外炸点空间三维坐标测量的问题,提出了基于二维PSD位置传感器的炸点位置测量方法,构建了基于二维PSD位置传感器的炸点三维坐标测量系统;基于双目视觉原理建立了炸点空间三维坐标测量数学模型;研究了被动探测系统在野外远距离下的标定技术;通过系统误差分解传递,分析了各参数的误差;在Matlab中分别绘制了炸点位置坐标3个维度的误差分布图,并分析了测量系统误差随炸点实际位置变化的分布情况;根据误差分布图得到了在理论100 m测试距离下X坐标最大测量误差约为0.292~0.303 m,Y坐标最大测量误差约为0.251~0.371 m,Z坐标最大测量误差0.270~0.336 m;最后通过静爆实验对测量方法正确性、被动探测系统标定技术可行性和测量系统功能性进行了验证,结果表明测量系统响应速度快且功能正常,被动探测系统标定技术具备可行性且操作方便,可适用于野外炸点位置的快速测量。 展开更多
关键词 psd位置传感器 炸点位置测量 双目视觉原理 被动探测标定 误差分析
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LociScan,a tool for screening genetic marker combinations for plant variety discrimination
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作者 Yang Yang Hongli Tian +5 位作者 Hongmei Yi Zi Shi Lu Wang Yaming Fan Fengge Wang Jiuran Zhao 《The Crop Journal》 SCIE CSCD 2024年第2期583-593,共11页
To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening m... To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening model based on the genetic algorithm(GA)and implemented in a software tool,Loci Scan.Ratio-based variety discrimination power provided the largest optimization space among multiple fitness functions.Among GA parameters,an increase in population size and generation number enlarged optimization depth but also calculation workload.Exhaustive algorithm afforded the same optimization depth as GA but vastly increased calculation time.In comparison with two other software tools,Loci Scan accommodated missing data,reduced calculation time,and offered more fitness functions.In large datasets,the sample size of training data exerted the strongest influence on calculation time,whereas the marker size of training data showed no effect,and target marker number had limited effect on analysis speed. 展开更多
关键词 Plant variety discrimination Genetic marker combination Variety discrimination power Genetic algorithm
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The Analysis of the Correlation between SPT and CPT Based on CNN-GA and Liquefaction Discrimination Research
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作者 Ruihan Bai Feng Shen +2 位作者 Zihao Zhao Zhiping Zhang Qisi Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1159-1182,共24页
The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires f... The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires field testing and canbe time-consuming and labor-intensive. In contrast, the cone penetration test (CPT) provides a more convenientmethod and offers detailed and continuous information about soil layers. In this study, the feature matrix based onCPT data is proposed to predict the standard penetration test blow count N. The featurematrix comprises the CPTcharacteristic parameters at specific depths, such as tip resistance qc, sleeve resistance f s, and depth H. To fuse thefeatures on the matrix, the convolutional neural network (CNN) is employed for feature extraction. Additionally,Genetic Algorithm (GA) is utilized to obtain the best combination of convolutional kernels and the number ofneurons. The study evaluated the robustness of the proposed model using multiple engineering field data sets.Results demonstrated that the proposed model outperformed conventional methods in predicting N values forvarious soil categories, including sandy silt, silty sand, and clayey silt. Finally, the proposed model was employedfor liquefaction discrimination. The liquefaction discrimination based on the predicted N values was comparedwith the measured N values, and the results showed that the discrimination results were in 75% agreement. Thestudy has important practical application value for foundation liquefaction engineering. Also, the novel methodadopted in this research provides new ideas and methods for research in related fields, which is of great academicsignificance. 展开更多
关键词 CNN liquefaction discrimination SPT CPT
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基于ZigBee网络和自适应PSD算法的路灯分布式节能控制方法
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作者 邵海亮 董华刚 +3 位作者 黑强虎 李伟 唐鹏伟 杨振仁 《计算技术与自动化》 2024年第1期56-60,共5页
当前照明系统缺乏分布式路灯动态化控制,浪费大量能源,为此,提出了基于ZigBee网络和自适应PSD算法的路灯分布式节能控制方法。通过ZigBee网络通信连接系统传感器、控制中心和照明终端,协调设备通信功能,实现信息快速传输储存。利用神经... 当前照明系统缺乏分布式路灯动态化控制,浪费大量能源,为此,提出了基于ZigBee网络和自适应PSD算法的路灯分布式节能控制方法。通过ZigBee网络通信连接系统传感器、控制中心和照明终端,协调设备通信功能,实现信息快速传输储存。利用神经网络处理信号数据,提高系统信号检测和处理效率。在此基础上,利用自适应PSD算法识别路灯信号动态特征,进行自适应信号检测,调节信号数据偏差,精确检测数据结果,增强系统节能控制稳定程度,实现路灯分布式节能控制。由实验结果可知,研究方法将分布式路灯检测精准度提高到99%,熔池宽度稳定在3.5W/mm,具有良好的检测精准度和控制稳定性,可以对路灯进行节能控制。 展开更多
关键词 路灯分布式节能控制 ZIGBEE网络 神经网络 自适应psd算法
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The Influence of Price Discrimination from Airports on the Route Development Behavior of Airlines
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作者 Daniel Schnitzler 《Journal of Civil Engineering and Architecture》 2024年第1期17-29,共13页
Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and t... Given the prominence and magnitude of airport incentive schemes,it is surprising that literature hitherto remains silent as to their effectiveness.In this paper,the relationship between airport incentive schemes and the route development behavior of airlines is analyzed.Because of rare and often controversial findings in the extant literature regarding relevant influencing variables for attracting airlines at an airport,expert interviews are used as a complement to formulate testable hypotheses in this regard.A fixed effects regression model is used to test the hypotheses with a dataset that covers all seat capacity offered at the 22 largest German commercial airports in the week 46 from 2004 to 2011.It is found that incentives from primary choice,as well as secondary choice airports,have a significant influence on Low Cost Carriers.Furthermore,Low Cost Carriers,in general,do not leave any of both types of airports when the incentives cease.In the case of Network Carriers,no case is found where one joins a primary choice airport and receives an incentive.Insufficient data between Network Carriers and secondary choice airports in the time when incentives have ceased means that no statement can be given. 展开更多
关键词 AIRLINE rout development price discrimination
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PSD-95基因DNA甲基化在睡眠剥夺相关疾病的作用研究进展
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作者 马江磊 张慧杰 王光明 《右江医学》 2024年第1期6-11,共6页
睡眠剥夺(SD)已成为世界各地普遍存在的问题,许多疾病的发生与睡眠不足有关。已经发现表观遗传机制与SD及相关疾病的发生发展密切相关,其中,DNA甲基化是最常见的表观遗传修饰,可影响基因表达。突触后密度蛋白-95(PSD-95)被认为是兴奋性... 睡眠剥夺(SD)已成为世界各地普遍存在的问题,许多疾病的发生与睡眠不足有关。已经发现表观遗传机制与SD及相关疾病的发生发展密切相关,其中,DNA甲基化是最常见的表观遗传修饰,可影响基因表达。突触后密度蛋白-95(PSD-95)被认为是兴奋性信号传递过程中重要的调节因子,SD后,PSD-95表达降低,表现出情绪改变和认知障碍等精神疾病症状。在慢性应激小鼠中,观察到血清素1A受体启动子区DNA甲基化水平增加,与抑郁症患者前额叶皮层PSD-95表达水平降低有关。然而,PSD-95基因的DNA甲基化水平与抑郁症表型无关。在精神分裂症患者中,SD的长度会加重疾病程度,且PSD-95基因DNA甲基化与精神分裂症有关。此外,结直肠癌的发病风险与SD或昼夜节律紊乱有关,而PSD-95基因DNA甲基化也可能成为治疗结直肠肿瘤的靶点。未来仍需要进一步深入探索PSD-95基因DNA甲基化在SD相关疾病中的作用及调节机制。 展开更多
关键词 睡眠剥夺 突触后密度蛋白-95 DNA甲基化 表观遗传
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PSD-95/nNOS相互作用抑制剂通过上调Sirt3减轻高糖诱导的神经元损伤
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作者 王刚 王沛 +1 位作者 金海涛 胡炜 《山西医科大学学报》 CAS 2023年第3期333-342,共10页
目的观察突触后密度蛋白95(postsynaptic density-95,PSD-95)/神经元型一氧化氮合酶(neuronal nitric oxide synthase,nNOS)相互作用抑制剂IC87201和ZL006对高糖诱导的神经元损伤的影响并探讨其可能的分子作用机制。方法从新生SD乳鼠中... 目的观察突触后密度蛋白95(postsynaptic density-95,PSD-95)/神经元型一氧化氮合酶(neuronal nitric oxide synthase,nNOS)相互作用抑制剂IC87201和ZL006对高糖诱导的神经元损伤的影响并探讨其可能的分子作用机制。方法从新生SD乳鼠中分离并培养海马神经元细胞。为了研究PSD-95/nNOS相互作用抑制剂IC87201和ZL006对高糖(HG)诱导的神经元损伤的影响,将海马神经元分为:常糖(normal glucose,NG)组、HG组(150 mmol/L D-葡萄糖诱导高糖损伤)、HG+DMSO组(DMSO预处理30 min再进行高糖处理)、HG+IC87201组(IC87201预处理30 min,再进行高糖处理)和HG+ZL006组(ZL006预处理30 min,再进行高糖处理);采用乳酸脱氢酶(lactate dehydrogenase,LDH)检测试剂盒检测神经元损伤,采用原位末端标记法(terminal-deoxynucleoitidyl transferase mediated nick end labeling,TUNEL)检测神经元凋亡,采用活性氧(reactive oxygen species,ROS)荧光探针检测ROS水平,采用丙二醛(malondialdehyde,MDA)检测试剂盒测量MDA含量,采用超氧化物歧化酶(superoxide dismutase,SOD)检测试剂盒测量SOD活性,采用Western blot方法检测Bax和Bcl-2蛋白表达水平。为了研究沉默信息调节因子3(silent information regulator 3,Sirt3)基因敲除对PSD-95/nNOS相互作用抑制剂IC87201和ZL006介导的高糖保护作用的影响,将海马神经元分为:NG组、HG+DMSO组、HG+IC87201+sh-scrambled组(sh-scrambled转染48 h,IC87201预处理30 min,再进行高糖处理)、HG+IC87201+sh-Sirt3组(sh-Sirt3转染48 h,IC87201预处理30 min,再进行高糖处理)、HG+ZL006+sh-scrambled组(sh-scrambled转染48 h,ZL006预处理30 min,再进行高糖处理)和HG+ZL006+sh-Sirt3组(sh-Sirt3转染48 h,ZL006预处理30 min,再进行高糖处理);采用Western blot方法检测Sirt3蛋白表达水平,采用TUNEL检测神经元细胞凋亡,采用ROS荧光探针检测ROS水平。结果与NG组比较,HG组和HG+DMSO组神经元损伤显著升高(P<0.01),凋亡神经元数量显著增加(P<0.01),促凋亡蛋白Bax表达水平显著升高(P<0.01),抗凋亡蛋白Bcl-2表达水平显著降低(P<0.01),ROS产生水平显著提高(P<0.01),MDA含量显著增加(P<0.01),SOD活性显著降低(P<0.01),Sirt3蛋白表达水平显著减少(P<0.01)。与HG组和HG+DMSO组比较,HG+IC87201组和HG+ZL006组神经元损伤显著降低(P<0.01),凋亡神经元数量显著下降(P<0.01),Bax蛋白表达水平显著降低(P<0.01),Bcl-2蛋白表达水平显著升高(P<0.01),ROS产生水平显著下降(P<0.01),MDA含量显著减少(P<0.01),SOD活性显著升高(P<0.01),Sirt3蛋白表达水平显著升高(P<0.01)。与HG+IC87201+sh-scrambled组比较,HG+IC87201+sh-Sirt3组Sirt3蛋白水平显著降低(P<0.01),凋亡神经元数量显著增加(P<0.01),ROS产生水平显著提高(P<0.01)。与HG+ZL006+sh-scrambled组比较,HG+ZL006+sh-Sirt3组Sirt3蛋白水平显著降低(P<0.01),凋亡神经元数量显著增加(P<0.01),ROS产生水平显著提高(P<0.01)。结论PSD-95/nNOS相互作用抑制剂IC87201和ZL006可以减少高糖诱导的神经元损伤,其机制可能与上调Sirt3蛋白表达相关。 展开更多
关键词 糖尿病脑病 高糖 海马神经元 psd-95/nNOS相互作用
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蒲金口服液对HIBD幼鼠脑组织PSD-95、NMDAR-2B表达的影响
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作者 李瑞星 马丙祥 +2 位作者 孔亚敏 张雪原 陈慧敏 《中国中医药现代远程教育》 2023年第7期166-169,共4页
目的探讨蒲金口服液对缺氧缺血性脑损伤(Hypoxic-ischemic brain damage,HIBD)幼鼠的神经保护机制。方法单侧颈总动脉结扎联合缺氧环境制备HIBD幼鼠模型。动物分为中药组、西药组、模型组、假手术组、空白组。中药组蒲金口服液0.1 mL/(k... 目的探讨蒲金口服液对缺氧缺血性脑损伤(Hypoxic-ischemic brain damage,HIBD)幼鼠的神经保护机制。方法单侧颈总动脉结扎联合缺氧环境制备HIBD幼鼠模型。动物分为中药组、西药组、模型组、假手术组、空白组。中药组蒲金口服液0.1 mL/(kg·d)灌胃;西药组单唾液酸四己糖神经节苷脂钠注射液3 mL/(kg·d)腹腔注射;余组生理盐水0.1 mL/(kg·d)灌胃,均每日1次,连续14 d。Morris水迷宫测试学习与记忆行为能力,尼氏染色观察脑组织神经元,透射电镜观察突触超微结构,Western Blot检测脑组织PSD-95、NMDAR-2B表达。结果蒲金口服液可改善HIBD幼鼠神经损伤,上调脑组织突触后密度蛋白95(PSD-95)、谷氨酸受体2B抗体(NMDAR-2B)表达(P<0.05)。结论蒲金口服液改善HIBD幼鼠神经行为学表现,可能与其调控PSD-95、NMDAR-2B表达,维护突触稳态有关。 展开更多
关键词 痿证 缺氧缺血性脑损伤 幼年大鼠 蒲金口服液 psd-95 NMDAR-2B 实验研究
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电针百会、神庭对大脑中动脉栓塞大鼠学习记忆功能和前额叶皮层GABAA受体及PSD-95表达的影响 被引量:4
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作者 夏金言 李钻芳 +1 位作者 杨嘉誉 林如辉 《中国康复医学杂志》 CAS CSCD 北大核心 2023年第6期730-736,共7页
目的:观察电针百会、神庭对MCAO大鼠学习记忆功能及前额叶皮层γ-氨基丁酸A型(gamma-aminobutyric acid,GABAA)受体及突触后密度蛋白-95(postsynaptic density protein-95,PSD-95)表达的影响,探讨电针对MCAO大鼠学习记忆功能的影响及作... 目的:观察电针百会、神庭对MCAO大鼠学习记忆功能及前额叶皮层γ-氨基丁酸A型(gamma-aminobutyric acid,GABAA)受体及突触后密度蛋白-95(postsynaptic density protein-95,PSD-95)表达的影响,探讨电针对MCAO大鼠学习记忆功能的影响及作用机制。方法:改良Longa线栓阻塞法制备左侧大脑中动脉栓塞(middle cerebral artery occlusion,MCAO)模型,将造模成功的雄性Sprague-Dawley大鼠随机分成模型组、电针组(百会、神庭)和电针非穴组,同时另设假手术组,每组10只。电针组和非穴组进行连续7d电针干预,假手术组和模型组不做任何处理。采用小动物磁共振成像仪检测干预前后大鼠脑梗死体积变化;Morris水迷宫评价大鼠学习记忆功能;HE染色观察缺血侧前额叶皮层病理变化;Western Blot法检测缺血侧前额叶皮层GABAA受体及PSD-95蛋白表达水平。结果:干预前各组大鼠脑梗死体积无显著性差异(P>0.05),随着干预时间延长,与模型组和非穴组相比,电针组行为学评分明显降低(P<0.05);电针组Morris水迷宫学习记忆测试逃避潜伏期缩短(P<0.05)。干预后,与模型组和非穴组相比,电针组脑梗死体积明显减小(P<0.01);电针组神经元密度和神经细胞数量明显增加;电针组前额叶皮层GABAA受体及PSD-95蛋白表达均明显上升(P<0.05),而模型组和非穴组之间无明显差异(P>0.05)。结论:电针百会、神庭能有效减轻脑缺血后神经损伤,改善学习记忆功能,可能与增加其前额叶皮层神经元数量,促进GABAA受体及PSD-95表达有关。 展开更多
关键词 γ-氨基丁酸A型受体 突触后密度蛋白-95 电针 脑缺血损伤 学习记忆功能障碍
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思维进化算法和神经网络结合的PSD非线性优化
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作者 李壮 辛志杰 +1 位作者 周进节 崔帅 《仪表技术与传感器》 CSCD 北大核心 2023年第3期110-113,121,共5页
针对位置敏感探测器(PSD)的非线性输出误差导致激光对中仪整体精度较差问题,建立思维进化算法(MEA)和LM-BP神经网络相结合的模型对其进行优化。该方法利用MEA较强的全局寻优能力,优化LM-BP网络的初始权阈值,找到最优个体构建MEA-LM-BP... 针对位置敏感探测器(PSD)的非线性输出误差导致激光对中仪整体精度较差问题,建立思维进化算法(MEA)和LM-BP神经网络相结合的模型对其进行优化。该方法利用MEA较强的全局寻优能力,优化LM-BP网络的初始权阈值,找到最优个体构建MEA-LM-BP神经网络。使用MATLAB软件编程构建BP神经网络,对实验获得的原始数据进行分析处理。仿真结果表明,该方法可以有效提高LM-BP法的泛化能力,同时具有更高的优化精度,可以极好地提高传感器的测量精度以及仪器整体精度。 展开更多
关键词 psd 非线性 思维进化算法 MEA-LM-BP法 神经网络
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基于PSD的汽轮机转子轴振动传感器
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作者 赵继兴 李晨 +2 位作者 马少华 雷英俊 李瑞君 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2023年第1期15-20,共6页
针对汽轮机转子轴振动的测量需求,文章研制一款基于位置敏感器件(position sensitive detector,PSD)的振动传感器。建立传感器的灵敏度模型,根据模型得出传感器的最优结构参数,并设计低噪声的信号处理电路;通过实验对该传感器进行标定... 针对汽轮机转子轴振动的测量需求,文章研制一款基于位置敏感器件(position sensitive detector,PSD)的振动传感器。建立传感器的灵敏度模型,根据模型得出传感器的最优结构参数,并设计低噪声的信号处理电路;通过实验对该传感器进行标定和测试,并与商用电涡流传感器进行对比测试。结果表明:振动传感器的灵敏度为0.33 V/mm,测量范围为2 mm,振幅分辨率为4μm,频率响应范围为10~325 Hz,重复实验标准差优于3μm;与商用电涡流传感器的测量结果具有良好一致性,可用于汽轮机转子轴振动的检测。 展开更多
关键词 振动测量 位置敏感器件(psd) 激光三角法 汽轮机转子轴振动
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Egg recognition and nestling discrimination in the Crested Myna(Acridotheres cristatellus):Size matters 被引量:1
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作者 Jinmei Liu Fangfang Zhang +1 位作者 Yuran Liu Wei Liang 《Avian Research》 SCIE CSCD 2023年第3期492-498,共7页
Most studies exploring abilities of hosts to detect brood parasitism are based on detecting colour and/or pattern differences among parasitic and host eggs or nestlings,while only few were focused on size differences.... Most studies exploring abilities of hosts to detect brood parasitism are based on detecting colour and/or pattern differences among parasitic and host eggs or nestlings,while only few were focused on size differences.True recognition and recognition by discordancy are used to explain cognitive mechanisms of host egg recognition;however,only a few studies have found that hosts use recognition by discordancy.This study investigated:1)whether egg and nestling recognitions in the Crested Myna(Acridotheres cristatellus) are based on size cues;2)whether the egg cognitive mechanism is recognition by discordancy based on size cues;and 3) whether the longer the experiment time,the higher the egg recognition rate.Our results showed that the Crested Myna uses egg or nestling size as a recognition cue while the egg and nestling colour and patterning are not associated with egg or nestling rejection,thus the cognitive mechanism of egg recognition in the Crested Myna is recognition by discordancy based on egg size cues.Furthermore,there is a rejection delay in time of egg rejection behaviour of the Crested Myna.Therefore,we suggest that the periodicity of egg rejection experiments could be appropriately extended,especially for species with relatively low egg recognition ability. 展开更多
关键词 Discordancy recognition Egg rejection Nest sanitation behaviour Nestling discrimination Rejection delay
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基于PSD模型的健康冰箱色彩设计策略研究 被引量:1
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作者 李安然 张学东 吴睿奇 《流行色》 2023年第2期10-12,共3页
为培养用户健康饮食和正确使用冰箱的行为习惯,通过设计引导用户的行为。首先,介绍了基于说服系统的PSD模型;其次,探讨健康冰箱的设计目标;再次,通过用户调研,完善健康冰箱说服语境;最后,PSD模型介入健康冰箱说服系统,结合色彩设计,提... 为培养用户健康饮食和正确使用冰箱的行为习惯,通过设计引导用户的行为。首先,介绍了基于说服系统的PSD模型;其次,探讨健康冰箱的设计目标;再次,通过用户调研,完善健康冰箱说服语境;最后,PSD模型介入健康冰箱说服系统,结合色彩设计,提出设计策略。为增加冰箱产品的差异性,将色彩设计与行为改变相结合,为面向行为改变的健康冰箱产品设计提供新方向。 展开更多
关键词 行为改变 psd说服模型 健康冰箱
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Performance of real‑time neutron/gamma discrimination methods
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作者 Shi‑Xing Liu Wei Zhang +5 位作者 Zi‑Han Zhang Shuang Lin Hong‑Rui Cao Cheng‑Xin Song Jin‑Long Zhao Guo‑Qiang Zhong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第1期102-110,共9页
Nuclear security usually requires the simultaneous detection of neutrons and gamma rays.With the development of crystalline materials in recent years,Cs2LiLaBr6(CLLB)dual-readout detectors have attracted extensive att... Nuclear security usually requires the simultaneous detection of neutrons and gamma rays.With the development of crystalline materials in recent years,Cs2LiLaBr6(CLLB)dual-readout detectors have attracted extensive attention from researchers,where real-time neutron/gamma pulse discrimination is the critical factor among detector performance parameters.This study investigated the discrimination performance of the charge comparison,amplitude comparison,time comparison,and pulse gradient_(m)ethods and the effects of a Sallen–Key filter on their performance.Experimental results show that the figure of merit(FOM)of all four methods is improved by proper filtering.Among them,the charge comparison method exhibits excellent noise resistance;moreover,it is the most_(s)uitable method of real-time discrimination for CLLB detectors.However,its discrimination performance depends on the parameters t_(s),t_(m),and t_(e).When t_(s)corresponds to the moment at which the pulse is at 10%of its peak value,t_(e)requires a delay of only 640–740 ns compared to t_(s),at which time the potentially optimal FOM of the charge comparison method at 3.1–3.3 MeV is greater than 1.46.The FOM obtained using the t_(m)value calculated by a proposed maximized discrimination difference model(MDDM)and the potentially optimal FOM differ by less than 3.9%,indicating that the model can provide good guidance for parameter selection in the charge comparison method. 展开更多
关键词 Charge comparison Maximized discrimination difference model Pulse filtering Real time n-γdiscrimination
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Multi-Path Attention Inverse Discrimination Network for Offline Signature Verification
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作者 Xiaorui Zhang Yingying Wang +2 位作者 Wei Sun Qi Cui Xindong Wei 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3057-3071,共15页
Signature verification,which is a method to distinguish the authenticity of signature images,is a biometric verification technique that can effectively reduce the risk of forged signatures in financial,legal,and other... Signature verification,which is a method to distinguish the authenticity of signature images,is a biometric verification technique that can effectively reduce the risk of forged signatures in financial,legal,and other business envir-onments.However,compared with ordinary images,signature images have the following characteristics:First,the strokes are slim,i.e.,there is less effective information.Second,the signature changes slightly with the time,place,and mood of the signer,i.e.,it has high intraclass differences.These challenges lead to the low accuracy of the existing methods based on convolutional neural net-works(CNN).This study proposes an end-to-end multi-path attention inverse dis-crimination network that focuses on the signature stroke parts to extract features by reversing the foreground and background of signature images,which effectively solves the problem of little effective information.To solve the problem of high intraclass variability of signature images,we add multi-path attention modules between discriminative streams and inverse streams to enhance the discriminative features of signature images.Moreover,a multi-path discrimination loss function is proposed,which does not require the feature representation of the samples with the same class label to be infinitely close,as long as the gap between inter-class distance and the intra-class distance is bigger than the set classification threshold,which radically resolves the problem of high intra-class difference of signature images.In addition,this loss can also spur the network to explore the detailed infor-mation on the stroke parts,such as the crossing,thickness,and connection of strokes.We respectively tested on CEDAR,BHSig-Bengali,BHSig-Hindi,and GPDS Synthetic datasets with accuracies of 100%,96.24%,93.86%,and 83.72%,which are more accurate than existing signature verification methods.This is more helpful to the task of signature authentication in justice and finance. 展开更多
关键词 Offline signatures biometric verification multi-path discrimination loss attention mechanisms inverse discrimination
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基于激光PSD的空间载荷指向测量系统
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作者 方厚招 薛景赛 +3 位作者 孙延博 贾奥男 王润泽 王瑞 《航天器环境工程》 CSCD 北大核心 2023年第2期179-183,共5页
为满足卫星载荷指向高精度测量需求,设计基于激光位置敏感探测器(PSD)的空间载荷指向测量系统。主要原理是:将激光发射至反射器(安装于载荷)处,经反射器反射到PSD光敏面后,PSD感应激光形成光电流,再经过电流-电压变换处理后输出给高精... 为满足卫星载荷指向高精度测量需求,设计基于激光位置敏感探测器(PSD)的空间载荷指向测量系统。主要原理是:将激光发射至反射器(安装于载荷)处,经反射器反射到PSD光敏面后,PSD感应激光形成光电流,再经过电流-电压变换处理后输出给高精度采集控制器,最后通过高精度采集控制器中的算法进行数据处理得到载荷指向的小角度变化。试验证明,该系统测量角度范围±0.15°,俯仰角和倾斜角测量精度优于0.002°,角度稳定性优于0.0004°(3.5 h)。该系统不仅可满足在轨因热变形等因素产生的载荷指向小角度转动测量要求,同时可满足地面测试中的小角度高精度测量需求。 展开更多
关键词 载荷指向 位置敏感探测器 小角度测量 高精度 高稳定性
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Sex effect on growth performance and marker-aided sex discrimination of seedlings of Populus deltoides
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作者 Yingnan Chen Huaitong Wu +4 位作者 Xiaogang Dai Weiqiang Li Yu Qiu Yonghua Yang Tongming Yin 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1639-1645,共7页
Sex has a significant effect on various traits among dioecious plants.In this analysis of the sex effect on the radial growth and wood density of numerous 20-yearold trees of Populus deltoides growing in a common gard... Sex has a significant effect on various traits among dioecious plants.In this analysis of the sex effect on the radial growth and wood density of numerous 20-yearold trees of Populus deltoides growing in a common garden,male trees performed better than the females in radial growth,but sex did not significantly affect wood density.Growth rate and wood density were weakly negatively correlated.Sex selection is also critical for controlling seed-hair pollution from P.deltoides plantations.However,because the juvenile period of P.deltoides lasts for years,a reliable technique to determine the sex of juveniles has been needed.Here we developed a marker-aided technique to discriminate the sexes of P.deltoides seedlings.This study provides essential information on target traits and a highly desirable genetic toolkit for accelerate breeding programs for this important tree species. 展开更多
关键词 Sex effect Wood quality Growth performance Marker-aided selection Sex discrimination
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Quantitative Method of Classification and Discrimination of a Porous Carbonate Reservoir Integrating K-means Clustering and Bayesian Theory
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作者 FANG Xinxin ZHU Guotao +2 位作者 YANG Yiming LI Fengling FENG Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期176-189,共14页
Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Wes... Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Western Iraq as an example,a new reservoir classification and discrimination method is established by using the K-means clustering method and the Bayesian discrimination method.These methods are applied to non-cored wells to calculate the discrimination accuracy of the reservoir type,and thus the main reasons for low accuracy of reservoir discrimination are clarified.The results show that the discrimination accuracy of reservoir type based on K-means clustering and Bayesian stepwise discrimination is strongly related to the accuracy of the core data.The discrimination accuracy rate of TypeⅠ,TypeⅡ,and TypeⅤreservoirs is found to be significantly higher than that of TypeⅢand TypeⅣreservoirs using the method of combining K-means clustering and Bayesian theory based on logging data.Although the recognition accuracy of the new methodology for the TypeⅣreservoir is low,with average accuracy the new method has reached more than 82%in the entire study area,which lays a good foundation for rapid and accurate discrimination of reservoir types and the fine evaluation of a reservoir. 展开更多
关键词 UPSTREAM resource exploration reservoir classification CARBONATE K-means clustering Bayesian discrimination CENOMANIAN-TURONIAN Iraq
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Discrimination and quantification of scar tissue by Mueller matrix imaging with machine learning
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作者 Xi Liu Yanan Sun +3 位作者 Weixi Gu Jianguo Sun Yi Wang Li Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第5期47-58,共12页
Scarring is one of the biggest areas of unmet need in the long-term success of glaucoma filtration surgery.Quantitative evaluation of the scar tissue and the post-operative structure with micron scale resolution facil... Scarring is one of the biggest areas of unmet need in the long-term success of glaucoma filtration surgery.Quantitative evaluation of the scar tissue and the post-operative structure with micron scale resolution facilitates development of anti-fibrosis techniques.However,the distinguishment of conjunctiva,sclera and the scar tissue in the surgical area still relies on pathologists'experience.Since polarized light imaging is sensitive to anisotropic properties of the media,it is ideal for discrimination of scar in the subconjunctival and episcleral area by characterizing small differences between proportion,organization and the orientation of the fibers.In this paper,we defined the conjunctiva,sclera,and the scar tissue as three target tissues after glaucoma filtration surgery and obtained their polarization characteristics from the tissue sections by a Mueller matrix microscope.Discrimination score based on parameters derived from Mueller matrix and machine learning was calculated and tested as a diagnostic index.As a result,the discrimination score of three target tissues showed significant difference between each other(p<0.001).The visualization of the discrimination results showed significant contrast between target tissues.This study proved that Mueller matrix imaging is effective in ocular scar discrimination and paves the way for its application on other forms of ocular fibrosis as a substitute or supplementary for clinical practice. 展开更多
关键词 Tissue discrimination glaucoma filtration surgery polarized light Mueller matrix machine learning.
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