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Visualization for Explanation of Deep Learning-Based Defect Detection Model Using Class Activation Map 被引量:1
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作者 Hyunkyu Shin Yonghan Ahn +3 位作者 Mihwa Song Heungbae Gil Jungsik Choi Sanghyo Lee 《Computers, Materials & Continua》 SCIE EI 2023年第6期4753-4766,共14页
Recently,convolutional neural network(CNN)-based visual inspec-tion has been developed to detect defects on building surfaces automatically.The CNN model demonstrates remarkable accuracy in image data analysis;however... Recently,convolutional neural network(CNN)-based visual inspec-tion has been developed to detect defects on building surfaces automatically.The CNN model demonstrates remarkable accuracy in image data analysis;however,the predicted results have uncertainty in providing accurate informa-tion to users because of the“black box”problem in the deep learning model.Therefore,this study proposes a visual explanation method to overcome the uncertainty limitation of CNN-based defect identification.The visual repre-sentative gradient-weights class activation mapping(Grad-CAM)method is adopted to provide visually explainable information.A visualizing evaluation index is proposed to quantitatively analyze visual representations;this index reflects a rough estimate of the concordance rate between the visualized heat map and intended defects.In addition,an ablation study,adopting three-branch combinations with the VGG16,is implemented to identify perfor-mance variations by visualizing predicted results.Experiments reveal that the proposed model,combined with hybrid pooling,batch normalization,and multi-attention modules,achieves the best performance with an accuracy of 97.77%,corresponding to an improvement of 2.49%compared with the baseline model.Consequently,this study demonstrates that reliable results from an automatic defect classification model can be provided to an inspector through the visual representation of the predicted results using CNN models. 展开更多
关键词 Defect detection VISUALIZATION class activation map deep learning EXPLANATION visualizing evaluation index
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Triptolide (PG-490) induces apoptosis of dendritic cells through sequential p38 MAP kinase phosphorylation and caspase 3 activation 被引量:41
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作者 LiuQ ChenT ChenH ZhangM LiN LuZ MaP CaoX 《第二军医大学学报》 CAS CSCD 北大核心 2004年第9期939-939,共1页
Dendritic cells (DCs) are the most potent antigen-presen ting cells that play crucial roles in the regulation of immune response. Triptol ide, an active component purified from the medicinal plant Tripterygium wilfor ... Dendritic cells (DCs) are the most potent antigen-presen ting cells that play crucial roles in the regulation of immune response. Triptol ide, an active component purified from the medicinal plant Tripterygium wilfor dii Hook F., has been demonstrated to act as a potent immunosuppressive drug c apab le of inhibiting T cell activation and proliferation. However, little is known a bout the effects of triptolide on DCs. The present study shows that triptolide d oes not affect phenotypic differentiation and LPS-induced maturation of murine DCs. But triptolide can dramatically reduce cell recovery by inducing apoptosis of DCs at concentration as low as 10 ng/ml, as demonstrated by phosphatidylserin e exposure, mitochondria potential decrease, and nuclear DNA condensation. Tript olide induces activation of p38 in DCs, which precedes the activation of caspase 3. SB203580, a specific kinase inhibitor for p38, can block the activation of caspase 3 and inhibit the resultant apoptosis of DCs. Our results suggest that t he anti-inflammatory and immunosuppressive activities of triptolide may be due, in part, to its apoptosis-inducing effects on DCs. 展开更多
关键词 PG-490 map kinase phosphorylation and caspase 3 activation TRIPTOLIDE
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磁共振T2-mapping评估Graves眼病活动性的价值
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作者 王璐 樊瑶 +2 位作者 龙健 张明巧 刘纯 《解放军医学杂志》 CAS CSCD 北大核心 2024年第1期70-74,共5页
目的探讨磁共振T_(2)-mapping在Graves眼病(GO)活动性评估方面的价值。方法收集2019年7月-2021年1月于重庆医科大学附属第一医院内分泌科就诊的GO患者64例,使用计算机对其进行简单随机分组,其中49例作为观察研究对象,另外15例进行诊断... 目的探讨磁共振T_(2)-mapping在Graves眼病(GO)活动性评估方面的价值。方法收集2019年7月-2021年1月于重庆医科大学附属第一医院内分泌科就诊的GO患者64例,使用计算机对其进行简单随机分组,其中49例作为观察研究对象,另外15例进行诊断试验评价。按照临床活动性评分(CAS)将49例GO患者分为活动组(CAS≥3分,48只患眼)与非活动组(CAS<3分,50只患眼)。同期招募31名健康志愿者作为正常对照组,共62只眼。所有人均行3.0T眼眶磁共振T_(2)-mapping成像。在T_(2)-mapping冠状位图像上测量上直肌、下直肌、内直肌、外直肌眼球后5个层面的T_(2)弛豫时间(T_(2)RT),每块眼外肌分别取眼球后5个层面的T_(2)RT最大值来代表该眼外肌的T_(2)RT,最后取4块眼外肌T_(2)RT中的最大值,以眼外肌最大T_(2)RT表示。比较活动组、非活动组与正常对照组间上述5个指标(上直肌T_(2)RT、下直肌T_(2)RT、内直肌T_(2)RT、外直肌T_(2)RT、眼外肌最大T_(2)RT)的差异;采用受试者工作特征(ROC)曲线分析上述5个指标对GO活动性评估的诊断价值,得出诊断阈值,然后利用另外15例GO患者进行诊断试验评价,确定诊断效能较高的指标及其诊断活动性的阈值。结果活动组所有眼外肌的T_(2)RT均明显高于非活动组及正常对照组,差异有统计学意义(P<0.001)。ROC曲线分析显示,上直肌、下直肌、内直肌、外直肌、眼外肌的最大T_(2)RT判断活动性的截断值分别为80.200 ms、97.045 ms、94.355 ms、85.750 ms、101.385 ms。利用另外15例GO患者进行诊断试验评价,综合评估敏感度、特异度、阳性预测值、阴性预测值较高的指标为下直肌T_(2)RT、眼外肌最大T_(2)RT,其判断活动性的截断值分别为97.045 ms、101.385 ms;敏感度分别为91.7%、93.8%;特异度均为80.0%。结论磁共振T_(2)-mapping序列对评估GO的活动性具有良好价值。临床上可选择测量下直肌T_(2)RT或眼外肌最大T_(2)RT协助评估GO的活动性。 展开更多
关键词 GRAVES眼病 磁共振T2-mapping 活动性评估
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Study Progress Analysis of Effluent Quality Prediction in Activated Sludge Process Based on CiteSpace
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作者 Kemeng Xue 《Journal of Water Resource and Protection》 CAS 2024年第6期450-465,共16页
In this paper, CiteSpace, a bibliometrics software, was adopted to collect research papers published on the Web of Science, which are relevant to biological model and effluent quality prediction in activated sludge pr... In this paper, CiteSpace, a bibliometrics software, was adopted to collect research papers published on the Web of Science, which are relevant to biological model and effluent quality prediction in activated sludge process in the wastewater treatment. By the way of trend map, keyword knowledge map, and co-cited knowledge map, specific visualization analysis and identification of the authors, institutions and regions were concluded. Furthermore, the topics and hotspots of water quality prediction in activated sludge process through the literature-co-citation-based cluster analysis and literature citation burst analysis were also determined, which not only reflected the historical evolution progress to a certain extent, but also provided the direction and insight of the knowledge structure of water quality prediction and activated sludge process for future research. 展开更多
关键词 Biological Model Effluent Quality Prediction activated Sludge Process CITESPACE Knowledge map Co-Citation Cluster Analysis
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Effects of Co_3O_4 nanocatalyst morphology on CO oxidation:Synthesis process map and catalytic activity 被引量:6
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作者 曾良鹏 李孔斋 +2 位作者 黄樊 祝星 李宏程 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期908-922,共15页
This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hy... This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies(i.e.,nanorods,nanosheets,and nanocubes) were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures(≤ 140℃).Nanorods can be synthesized in CoCl2 solution,while Co(NO3)2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature(higher than 140 ℃) results in the formation of nanocubes in either Co(NO3)2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^(3+) on the surface,much higher reducibility,and better oxygen desorption capacity. 展开更多
关键词 Cobalt oxide nanocatalyst Synthesis process map Morphology effect Catalytic activity Carbon monoxide oxidation
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Continuous gradient fusion class activation mapping: segmentation of laser-induced damage on large-aperture optics in dark-field images 被引量:1
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作者 Yueyue Han Yingyan Huang +5 位作者 Hangcheng Dong Fengdong Chen Fa Zeng Zhitao Peng Qihua Zhu Guodong Liu 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2024年第1期30-41,共12页
Segmenting dark-field images of laser-induced damage on large-aperture optics in high-power laser facilities is challenged by complicated damage morphology, uneven illumination and stray light interference. Fully supe... Segmenting dark-field images of laser-induced damage on large-aperture optics in high-power laser facilities is challenged by complicated damage morphology, uneven illumination and stray light interference. Fully supervised semantic segmentation algorithms have achieved state-of-the-art performance but rely on a large number of pixel-level labels, which are time-consuming and labor-consuming to produce. LayerCAM, an advanced weakly supervised semantic segmentation algorithm, can generate pixel-accurate results using only image-level labels, but its scattered and partially underactivated class activation regions degrade segmentation performance. In this paper, we propose a weakly supervised semantic segmentation method, continuous gradient class activation mapping(CAM) and its nonlinear multiscale fusion(continuous gradient fusion CAM). The method redesigns backpropagating gradients and nonlinearly activates multiscale fused heatmaps to generate more fine-grained class activation maps with an appropriate activation degree for different damage site sizes. Experiments on our dataset show that the proposed method can achieve segmentation performance comparable to that of fully supervised algorithms. 展开更多
关键词 class activation maps laser-induced damage semantic segmentation weakly supervised learning
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Value Analysis among the Parties on Imported Product in Indonesia Using Process Activity Mapping: Freight Forwarder, Distributor, and Retailer
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作者 Megita Ryanjani Tanuputri Ravipim Chaveesuk Adi Djoko Guritno 《Journal of Food Science and Engineering》 2017年第5期274-282,共9页
National logistics system in Indonesia can be categorized as inefficient logistics system due to current number of non-value added (NVA) activities. The unreliable National logistics system and the complexity of dis... National logistics system in Indonesia can be categorized as inefficient logistics system due to current number of non-value added (NVA) activities. The unreliable National logistics system and the complexity of distribution system are the big obstacles. This study aims to analyze the value and to propose recommendation for further improvement of National distribution system for imported product. This study employed convenience sampling through in-depth interview to analyze the activity in freight forwarder (FF), distributor and retailer. To demonstrate and analyze the activity process in each party, Process Activity Mapping (PAM) was used as a tool. The study results showed that the delivery speed in Jakarta (8.4 min/km) is slower than that of Surabaya (6.6 min/km). The government support through creating adequate infrastructure, good bureaucracy system and good collaboration directly affects the activities of FF, distributor and retailer. Improving FF performance in a timely and reliable manner is required to reduce errors that may occur. Moreover, encouraging the practice of cold chain management is also necessary in distributing the product throughout Indonesia. The pull strategy can be chosen by retailer to eliminate storage activity. Meanwhile, the use of information technology (IT) system is essential to encourage better inventory management, database management and sharing information in distributor and retailer stage. 展开更多
关键词 Value analysis import Indonesia logistics system process activity mapping.
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Comparison of detection results of hypoxic-ischemic encephalopathy at different degrees in infant patients between brain electrical activity mapping, transcranial Doppler sonography and computer tomography examinations
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作者 Dongruo He Xiaoying Xu +1 位作者 Yinghui Zhang Guochao Han 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期379-381,共3页
BACKGROUND: It has been proved that brain electrical activity mapping (BEAM) and transcranial Doppler (TCD) detection can reflect the function of brain cell and its diseased degree of infant patients with moderat... BACKGROUND: It has been proved that brain electrical activity mapping (BEAM) and transcranial Doppler (TCD) detection can reflect the function of brain cell and its diseased degree of infant patients with moderate to severe hypoxic-ischemic encephalopathy (HIE). OBJECTIVE: To observe the abnormal results of HIE at different degrees detected with BEAM and TCD in infant patients, and compare the detection results at the same time point between BEAM, TCD and computer tomography (CT) examinations. DESIGN : Contrast observation SETTING: Departments of Neuro-electrophysiology and Pediatrics, Second Affiliated Hospital of Qiqihar Medical College. PARTICIPANTS: Totally 416 infant patients with HIE who received treatment in the Department of Newborn Infants, Second Affiliated Hospital of Qiqihar Medical College during January 2001 and December 2005. The infant patients, 278 male and 138 female, were at embryonic 37 to 42 weeks and weighing 2.0 to 4.1 kg, and they were diagnosed with CT and met the diagnostic criteria of HIE of newborn infants compiled by Department of Neonatology, Pediatric Academy, Chinese Medical Association. According to diagnostic criteria, 130 patients were mild abnormal, 196 moderate abnormal and 90 severe abnormal. The relatives of all the infant patients were informed of the experiment. METHOOS: BEAM and TCD examinations were performed in the involved 416 infant patients with HIE at different degrees with DYD2000 16-channel BEAM instrument and EME-2000 ultrasonograph before preliminary diagnosis treatment (within 1 month after birth) and 1,3,6,12 and 24 months after birth, and detected results were compared between BEAM, TCD and CT examinations. MAIN OUTCOME MEASURES: Comparison of detection results of HIE at different time points in infant patients between BEAM. TCD and CT examinations. RESULTS: All the 416 infant patients with HIE participated in the result analysis. (1) Comparison of the detected results in infant patients with mild HIE at different time points after birth between BEAM, TCD and CT examinations: BEAM examination showed that the recovery was delayed, and the abnormal rate of BEAM examination was significantly higher than that of CT examination 1 and 3 months after birth [55.4%(72/130)vs. 17.0% (22/130 ),x^2=41.66 ;29.2% ( 38/130 ) vs. 6.2% ( 8/130 ), x^2=23.77, P 〈 0.01 ], exceptional patients had mild abnormality and reached the normal level in about 6 months. TCD examination showed that the disease condition significantly improved and infant patients with HIE basically recovered 1 or 2 months after birth, while CT examination showed that infant patients recovered 3 or 4 months after birth. (2) Comparison of detection results of infant patients with moderate HIE at different time points between BEAM, TCD and CT examinations: The abnormal rate of BEAM examination was significantly higher than that of CT examination 1,3,6 and 12 months after birth [90.8% (178/196),78.6% (154/196),x^2=4.32,P 〈 0.05;64.3% (126/196),43.9% (86/196) ,x^2=16.44 ;44.9% (88/196) ,22.4% (44/196),x^2=22.11 ;21.4% (42/196), 10.2% (20/196),x^2=9.27, P 〈 0.01]. BEAM examination showed that there was still one patient who did not completely recovered in the 24^th month due to the relatives of infant patients did not combine the treatment,. TCD examination showed that the abnormal rate was 23.1%(30/196)in the 1^st month after birth, and all the patients recovered to the normal in the 3^rd month after birth, while CT examination showed that mild abnormality still existed in the 24^th month after birth (1.0% ,2/196). (3) Comparison of detection results of infant patients with severe HIE at different time points between BEAM, TCD and CT examinations: The abnormal rate of BEAM examination was significantly higher than that of CT examination in the 1^st, 3^rd, 6^th and 12^th months after birth[86.7% (78/90),44.4% (40/90),x^2=35.53;62.2% (56/90),31.1% (28/90),x^2=17.51 ;37.8% (34/90),6.7% (6/90), x^2=27.14, P 〈 0.01]. BEAM examination showed that mild abnormality still existed in 4 infant patients in the 24^th month after birth. TCD examination showed that the abnormal rate was 11.1% (10/90) in the 3^rd month after birth, and all the infant patients recovered in the 6^th month after birth. CT examination showed that the abnormal rate was 6.7%(6/90) in the 12^th month after birth, and all of infant patients recovered to the normal in the 24^th month after birth.CONCLUSION : BEAM is the direct index to detect brain function of infant patients with HIE, and positive reaction is still very sensitive in the tracking detection of convalescent period. The positive rate of morphological reaction in CT examination is superior to that in TCD examination, and the positive rate is very high in the acute period of HIE in examination. 展开更多
关键词 HIE Comparison of detection results of hypoxic-ischemic encephalopathy at different degrees in infant patients between brain electrical activity mapping transcranial Doppler sonography and computer tomography examinations
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Active Mapping防止NIDS误报和漏报的重要手段
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作者 都林 叶小列 《计算机安全》 2004年第9期47-48,共2页
关键词 网络入侵检测系统 NIDS TCP/IP协议 activE mapPING
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An Activity Recognition System at Home Based on CO2 Sensors
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作者 Hiroyuki Matsubara 《Journal of Computer and Communications》 2023年第11期64-77,共14页
Activity recognition of indoor occupants using indirect sensing with less privacy violation is one of the hot research topics. This paper proposes a CO<sub>2</sub> sensor-based indoor occupant activity mon... Activity recognition of indoor occupants using indirect sensing with less privacy violation is one of the hot research topics. This paper proposes a CO<sub>2</sub> sensor-based indoor occupant activity monitoring system. Using the IoT sensor node that contains CO<sub>2</sub> sensors, the measured CO<sub>2</sub> concentrations in three locations (laboratory, office, and bedroom) were stored in a cloud server for up to 35 days starting July 1, 2023. The CO<sub>2</sub> measurements stored at 30-second intervals were statistically processed to produce a heat-mapped display of the hourly average or maximum CO<sub>2</sub> concentration. From the heatmap visualizations of CO<sub>2</sub> concentration, the proposed system estimated meeting, heating water using a portable stove, and sleep for the occupants’ activity recognition. 展开更多
关键词 activity Recognition CO2 Sensor Internet of Things (IoT) Low Privacy-Intrusion Heat map
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基于MAP法和HAP法的剩余污泥中磷回收技术研究进展
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作者 滕俊 罗进财 +1 位作者 庞福静 董姗燕 《四川环境》 2023年第4期328-337,共10页
剩余污泥中磷的回收利用是实现污水和剩余污泥中磷元素循环利用的有效途径。综述了磷酸铵镁结晶法(MAP法)和磷酸钙结晶法(HAP法)两种磷回收技术,指出两种方法均是有效的磷回收技术,二者反应条件对磷回收的影响具有一定的相似性,不同之... 剩余污泥中磷的回收利用是实现污水和剩余污泥中磷元素循环利用的有效途径。综述了磷酸铵镁结晶法(MAP法)和磷酸钙结晶法(HAP法)两种磷回收技术,指出两种方法均是有效的磷回收技术,二者反应条件对磷回收的影响具有一定的相似性,不同之处在于MAP法可以同时将污水中的氨氮和磷酸盐回收去除,而HAP法适用于含磷废水中磷的去除回收;阐述了晶种是促进产物生成效率和提高产物纯度的有效方法,而污泥中有机物、相关离子或重金属等干扰因素则对产物生成效率产生一定影响;最后提出污泥厌氧发酵过程中有机物及其转化与磷释放和磷回收机制的影响将是今后的研究重点,以实现磷和有机酸等物质的同步回收利用。 展开更多
关键词 剩余污泥 磷回收 map HAP法 晶种
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基于脑电信息的图感认知响应规律及其量化分析方法 被引量:1
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作者 伊鹏 田兴辉 +3 位作者 刘广斗 魏庆冰 王帅 刘衍聪 《图学学报》 CSCD 北大核心 2024年第3期624-630,共7页
“图”是人类感知世界的重要媒介,图感认知是大脑认知思维中平面图元与三维形体间形成有效转换的关键通道,但人脑在接受图形输入、完成认知处理并实现知识输出的过程是认知心理学和脑科学交叉学科。目前缺乏充分的研究方法和理论基础,... “图”是人类感知世界的重要媒介,图感认知是大脑认知思维中平面图元与三维形体间形成有效转换的关键通道,但人脑在接受图形输入、完成认知处理并实现知识输出的过程是认知心理学和脑科学交叉学科。目前缺乏充分的研究方法和理论基础,因此针对图感认知过程不清晰及认知分析方法缺乏等问题,根据认知事件的脑电位相关性理论,以二维投影图和三维模型为图感认知对象,设计脑电认知测试实验并分析P300电位变化情况。结果表明:图感认知相关部位主要为大脑的前半部分左额叶位置;P300电位值可以用于反映大脑的图感认知程度,大脑对图像内容的接受能力越强,P300电位峰值越低。对比不同样本P300电位变化,可对图感认知过程进行分析,形成对图感认知能力的量化分析方法,提高图感认知内容对大脑的输入效率,对揭示图感输入和认知机理具有启示意义,并为图像交互深度应用反馈优化提供有效依据。 展开更多
关键词 图感认知 脑电波 P300电位 脑地形图 脑电实验
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鄂尔多斯活动地块及边界带1∶50万地震构造图编制 被引量:1
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作者 雷启云 郑文俊 +3 位作者 王银 余思汗 沈旭章 郝明 《地震科学进展》 2024年第1期65-74,共10页
地震构造图是综合反映特定地区地震构造环境和地震活动水平的基础性图件,鄂尔多斯活动地块及边界带1∶50万地震构造图是国家重点研发计划“鄂尔多斯活动地块边界带动力学模型与强震危险性研究”项目的一个专题成果。该图以鄂尔多斯活动... 地震构造图是综合反映特定地区地震构造环境和地震活动水平的基础性图件,鄂尔多斯活动地块及边界带1∶50万地震构造图是国家重点研发计划“鄂尔多斯活动地块边界带动力学模型与强震危险性研究”项目的一个专题成果。该图以鄂尔多斯活动地块及边界带为编图范围,参照地震行业有关地震构造图编制标准和数据库标准,在系统收集和整理区域地理信息、地质、活动构造、地震、地球物理等资料的基础上,开展高分辨卫星影像解译,吸收项目最新研究成果,建设了编图所需的基础数据库;通过资料矢量化、地层界线修改、断层修改、图面修饰、图件复核等环节,编制成鄂尔多斯活动地块及边界带1∶50万地震构造图。该图反映了由银川盆地—贺兰山、弧形构造束、渭河盆地、山西地堑系、河套盆地等活动构造单元组成的鄂尔多斯活动地块边界带,以及相邻地块有关地震构造的最新资料,完善了鄂尔多斯地块及边界带活动构造几何学和运动学图像,建成了区域地震构造基础数据库。 展开更多
关键词 鄂尔多斯 活动地块 地块边界带 地震构造图
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激动标测和起搏标测联合指引下解剖消融治疗特发性右室流出道室性早搏的效果
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作者 白中乐 白雪洋 +4 位作者 洪晋 王琎 陈晓伟 郭树领 赵平 《河南医学研究》 CAS 2024年第19期3465-3469,共5页
目的探讨激动标测和起搏标测联合指引下解剖消融治疗特发性右室流出道(RVOT)室性早搏的临床价值。方法回顾性分析2023年1—10月在郑州大学第一附属医院心血管内科和许昌市中心医院心血管内科住院接受室性早搏射频消融术的36例患者的资料... 目的探讨激动标测和起搏标测联合指引下解剖消融治疗特发性右室流出道(RVOT)室性早搏的临床价值。方法回顾性分析2023年1—10月在郑州大学第一附属医院心血管内科和许昌市中心医院心血管内科住院接受室性早搏射频消融术的36例患者的资料,经电生理检查证实室性早搏来源于RVOT,根据术中室性早搏数量多少灵活采用激动标测和或起搏标测找到靶点进行对应肺动脉根部瓣下和瓣上联合消融,分析该方法即刻及3个月成功率。结果术中室性早搏数量少的患者也可以快速有效地进行导管消融术并取得满意的远期效果。结论激动标测和起搏标测联合指引下解剖消融治疗特发性RVOT室性早搏临床可行,效果较好。 展开更多
关键词 室性早搏 激动标测 起搏标测 射频消融 右室流出道
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分数阶忆阻Henon映射的可控多稳定性及其视频加密应用
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作者 张红伟 付常磊 +4 位作者 潘志翔 丁大为 王金 杨宗立 刘涛 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第18期38-53,共16页
基于局部有源离散忆阻器构建一种能够产生任意数量共存吸引子的分数阶忆阻Henon映射.该映射的不动点数量由忆阻器内部参数控制,实现可控的同质多稳定性,适合基于混沌的工程应用.通过相图、分岔图、最大Lyapunov指数和吸引盆等方法揭示... 基于局部有源离散忆阻器构建一种能够产生任意数量共存吸引子的分数阶忆阻Henon映射.该映射的不动点数量由忆阻器内部参数控制,实现可控的同质多稳定性,适合基于混沌的工程应用.通过相图、分岔图、最大Lyapunov指数和吸引盆等方法揭示该映射的复杂动力学行为.数值模拟结果表明,该分数阶映射能够产生各种周期轨道、混沌吸引子和倍周期分岔等现象.随后使用ARM数字平台实现该系统,实验结果验证其物理可实现性.最后,基于该映射设计一种视频加密算法,并通过安全性分析验证该加密算法能够有效保证视频的安全传输. 展开更多
关键词 分数阶Henon映射 局部有源离散忆阻器 可控多稳定性 视频加密
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国际基于自我决定理论的儿童青少年体育活动研究现状与展望
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作者 尹雪娟 刘海元 黄先锋 《西安体育学院学报》 北大核心 2024年第1期37-51,共15页
为考察国际基于自我决定理论的儿童青少年体育活动研究的发展脉络和最新进展,运用科学计量学中的关键词共现、关键词聚类和可视化技术等方法对2000—2022年Web of Science核心合集数据库相关研究文献进行分析。结果发现:中国在亚洲国家... 为考察国际基于自我决定理论的儿童青少年体育活动研究的发展脉络和最新进展,运用科学计量学中的关键词共现、关键词聚类和可视化技术等方法对2000—2022年Web of Science核心合集数据库相关研究文献进行分析。结果发现:中国在亚洲国家中产出领先;历年研究呈现从宏观到微观、从单一到多重、从横断到纵横结合、从解决到预防、从验证到应用、从开拓到回顾的发展趋势,最新研究体现出重视结构化问卷、研究设计联系实际情境和纳入各种心理学变量的特点;已有研究存在针对特殊群体、干预的作用路径、系统化干预项目设计方法等方面的局限。对我国相关研究的启示:对热度仍持续的主题继续优化研究设计;对基本达到饱和的主题结合实际推进本土研究;利用多重变量关系路径、多元干预模型、跨情境研究、横向与纵向相结合等开展实证研究;编制、修订中国版的相关问卷。 展开更多
关键词 自我决定理论 儿童青少年 体育活动 研究主题 知识图谱
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基于电子鼻和气质联用分析萌芽大蒜挥发性物质差异
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作者 韩颖 易宇文 +5 位作者 何莲 邓静 胡金祥 吴华昌 石莉芳 杨会珍 《食品工业科技》 CAS 北大核心 2024年第5期243-252,共10页
为探究萌芽期大蒜挥发性物质的差异,采用电子鼻、捕集阱顶空-气质联用仪(Trap head space-gas chromatography-mass spectrometry,HS-Trap-GC-MS)结合正交偏最小二乘法判别分析(Orthogonal partial least squares discriminant analysis... 为探究萌芽期大蒜挥发性物质的差异,采用电子鼻、捕集阱顶空-气质联用仪(Trap head space-gas chromatography-mass spectrometry,HS-Trap-GC-MS)结合正交偏最小二乘法判别分析(Orthogonal partial least squares discriminant analysis,OPLS-DA)、香气活度值、差异性热图、相关性分析分析大蒜萌芽在0、24、48、72、96 h挥发性物质的差异。电子鼻结合OPLS-DA建立预测模型其预测能力达96.00%。GC-MS分析表明:含硫化合物是不同萌芽期大蒜的主要共有挥发性物质,含硫化合物的相对含量随萌芽时间的延长而呈递减趋势,而种类呈现出递增趋势;二烯丙基二硫醚是样品在萌芽过程中含量降低最多的物质。二烯丙基四硫醚、烯丙硫醇是样品共有关键化合物。差异性热图分析显示:除共有物质含量差异外,硫化丙烯、己醛、叠氮二羧酸二叔丁酯、丙烯醇、6-甲基-2-庚炔、5-甲基噻二唑、2-亚乙基-1,3-二硫烷、2-丙-2-炔基磺酰基丙烷、2,5-二甲基噻吩、2,5-二甲基呋喃、1-戊烯-3-醇、1,3-二噻烷的缺失进一步加大了未萌芽和萌芽大蒜气味的差异。萌芽大蒜主要共有挥发性物质的种类随萌芽时间的延长呈现递增趋势。大蒜主要挥发性物质与电子鼻大多数传感器存在显著相关性。大蒜的气味强度会随萌芽时间的延长而逐步减弱。 展开更多
关键词 萌芽大蒜 气相色谱-质谱联用法 电子鼻 正交偏最小二乘判别分析 香气活度值 差异 性热图 相关性分析
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原发失眠病人脑电波及脑电频带功率与事件相关电位P300的相关性
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作者 韩婕 邵明菊 +1 位作者 高呈飞 赵丽霞 《青岛大学学报(医学版)》 CAS 2024年第3期422-424,共3页
目的探讨原发失眠病人脑电波、脑电频带功率与事件相关电位P300的相关性,为评估原发失眠对大脑功能及认知功能的影响提供客观依据。方法选取原发性失眠病人31例为研究对象(失眠组),以正常成人31例为对照(正常组),分别进行常规脑电监测... 目的探讨原发失眠病人脑电波、脑电频带功率与事件相关电位P300的相关性,为评估原发失眠对大脑功能及认知功能的影响提供客观依据。方法选取原发性失眠病人31例为研究对象(失眠组),以正常成人31例为对照(正常组),分别进行常规脑电监测、事件相关电位P300(P3a及P3b)检查,分析脑电波占比、脑电频带功率及P3a和P3b潜伏期、波幅等数据及其相关性。结果失眠组与正常组P3a和P3b潜伏期及波幅、脑电α波及β波占比、FTT-β频带功率、FTT-总频带功率差异均具有统计学意义(Z=-6.84~-1.99,P<0.05)。脑电β波占比及FTT-β频带功率与P3b潜伏期呈正相关(r=0.483、0.517,P<0.05);脑电β波占比及FTT-β频带功率与P3b波幅呈负相关(r=-0.540、-0.691,P<0.01)。结论失眠病人脑电β波及FTT-β频带功率增加,事件相关电位P300改变,这可为评估失眠引起脑功能改变及认知功能障碍提供客观依据。 展开更多
关键词 入睡和睡眠障碍 脑电波 脑地形图 事件相关电位 P300 认知功能障碍
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多视野精细分析下的弱监督目标定位算法
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作者 张英俊 贾聪聪 谢斌红 《计算机工程与设计》 北大核心 2024年第6期1750-1756,共7页
针对多尺度目标定位精度较差,难以捕获完整目标边界的问题,设计一种多视野精细分析模块并融入通道与空间注意力机制抑制背景噪声的干扰,获取多尺度目标的高分辨率特征。利用随机特征选取模块获取特征图随机位置的组合,聚合多个位置图获... 针对多尺度目标定位精度较差,难以捕获完整目标边界的问题,设计一种多视野精细分析模块并融入通道与空间注意力机制抑制背景噪声的干扰,获取多尺度目标的高分辨率特征。利用随机特征选取模块获取特征图随机位置的组合,聚合多个位置图获取最具辨别性的位置及其它位置的信息,融合浅层生成的类激活图与聚合类激活图获取细粒度位置信息,捕获完整的目标边界。与现有的弱监督定位方法相比,在解决多尺度目标定位效果差和局部最优问题上具有一定的优势。 展开更多
关键词 弱监督学习 目标定位 多尺度特征融合 注意力机制 全局平均池化 类激活图 正则化
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基于活动需求的校园空间认知研究——以武汉大学为例
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作者 张霞 徐思行 《华中建筑》 2024年第5期47-51,共5页
建筑环境更关注中等尺度维度,了解使用者对此类环境的意象,对于环境的设计与优化具有重要意义。现有研究集中在空间认知规律方面,缺乏对校园空间认知与其他多种影响因素的关联分析。以环境行为认知理论为基础,通过手绘认知地图的定量分... 建筑环境更关注中等尺度维度,了解使用者对此类环境的意象,对于环境的设计与优化具有重要意义。现有研究集中在空间认知规律方面,缺乏对校园空间认知与其他多种影响因素的关联分析。以环境行为认知理论为基础,通过手绘认知地图的定量分析,空间句法分析与POI分析等方法,深入探索校园空间认知规律,最后对校园空间进行评估并提出优化建议。研究发现:①空间结构对空间认知具有决定性影响;②必要活动需求对空间认知的影响大于自发活动需求;③环境或建筑的风格以及纪念意义可以对认知起到较大程度的积极或消极影响。 展开更多
关键词 空间认知 认知地图 空间句法 活动需求 POI(兴趣点)
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