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基于IHHO-Stacking集成模型的车辆驾驶性评估
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作者 莫易敏 王相 +2 位作者 王哲 蒋华梁 李琼 《汽车技术》 北大核心 2025年第3期39-45,共7页
为解决车辆驾驶性主观评价一致性差及客观评价无法反映主观感受的问题,提出了一种基于堆叠(Stacking)集成学习方法的评价模型,首先研究了车辆加速工况特性,定义了工况驾驶性客观评价指标,使用评价指标作为输入特征训练Stacking集成模型... 为解决车辆驾驶性主观评价一致性差及客观评价无法反映主观感受的问题,提出了一种基于堆叠(Stacking)集成学习方法的评价模型,首先研究了车辆加速工况特性,定义了工况驾驶性客观评价指标,使用评价指标作为输入特征训练Stacking集成模型,并且使用改进的哈里斯鹰优化(IHHO)算法优化了Stacking集成模型,提高了预测性能。最后通过道路试验表明,IHHO-Stacking集成模型的性能均优于单个机器学习模型,IHHO-Stacking集成模型预测合格率达95%,能够更有效完成驾驶性评价。 展开更多
关键词 驾驶性 主观评价 改进的哈里斯鹰算法 STACKinG 集成模型 客观评价
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Evaluation Test Research of DR Inspection System for Circumferential Welds in Long Distance Pipeline
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作者 WANG Changjiang WANG Xue +4 位作者 ZHANG Shimin ZHAO Yan LYU Xinyu ZHONG Qian ZHOU Guangyan 《材料导报》 EI CAS CSCD 北大核心 2024年第22期223-229,共7页
Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digit... Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digital radiographic testing and fully evaluate the integrated system inspection ability of equipment,personnel,and processes,a scientific and standardized evaluation method to the system is very necessary.Here investigates the precedents of relevant non-destructive testing evaluation methods at home and abroad,considers the testing characteristics of DR equipment,develops a complete set of DR testing system evaluation procedures.It deeply studies the adaptability methods of program processes from defect production to slicing processing and data statistical calculation for digital radiographic testing evaluation.To check the repeatability and reliability of the detectable system,five process welds with 200 real metallographic defects were fabricated in the laboratory.From the detected results,the DR system has good repeatability in image quality,and the detectable defect size reaches 0.85 mm under achieving 90%detection probability at a confidence level of 95%,the error of detected defect length is±2 mm,and the error of detected defect localization is±5 mm.The qualitative and quantitative detection of defects are accurate and reliable.The test further confirmed the reliable detection ability of the DR detection system,and fully validated the scientific and practical evaluation method designed.The research on the evaluation test method can serve as an important link in the quality control system for the on-site application of digital ray equipment in long-distance pipelines.The designed program,test,and evaluation content can serve as an important basis for the formulation of relevant specifications or standards. 展开更多
关键词 digital ray evaluation test REPEATABILITY RELIABILITY
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基于机器学习和InSAR技术的滑坡易发性动态评价
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作者 陈志波 李鼎兴 +2 位作者 陈澄 黄卫 唐雪峰 《自然灾害学报》 北大核心 2025年第2期56-65,共10页
东南山地丘陵区因其特殊的气候条件与地质环境导致滑坡灾害具有群发性、突发性的特点。而现有的滑坡易发性评价方法多考虑静态的评价因子,无法反映东南山地丘陵区滑坡的动态特征。因此,需结合动态因子提高评价结果的时效性。文中以东南... 东南山地丘陵区因其特殊的气候条件与地质环境导致滑坡灾害具有群发性、突发性的特点。而现有的滑坡易发性评价方法多考虑静态的评价因子,无法反映东南山地丘陵区滑坡的动态特征。因此,需结合动态因子提高评价结果的时效性。文中以东南山地丘陵区的大田县为研究区,选取坡度、坡向、地表起伏度、地层岩性、归一化植被指数以及年均降雨量6个评价因子,通过信息量(information value,IV)模型与逻辑回归(logistic regression,LR)模型、随机森林(random forest,RF)模型进行滑坡易发性建模并进行合理性检验与精度检验。利用SBAS-InSAR技术反演研究区地表形变速率,结合滑坡易发性区划结果构建动态评价矩阵实现研究区的滑坡易发性动态评价。结果表明,随机森林模型的受试者工作特性(receiver operating characteristic,ROC)曲线下面积(area under curve,AUC)值最大(0.851),可用此方法进行东南山地丘陵区的滑坡易发性分区。在已知的滑坡中,13处滑坡稳定性较差,83处滑坡稳定性一般,150处滑坡较为稳定。通过绘制稳定性较差滑坡的时间序列形变曲线发现,东南山地丘陵区影响滑坡稳定性的主要因素为季节性降雨。 展开更多
关键词 滑坡 东南山地丘陵区 inSAR 易发性评价 机器学习方法
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Cinco-Ley模型在评价水力压裂效果中的应用及确定井控的原始地质储量
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作者 陈元千 《断块油气田》 北大核心 2025年第4期529-535,共7页
水力压裂技术的实施,是提高井产能和增加气藏采收率的重要手段。目前在国际上天然气的开采,主要集中于深层的致密气(k=0.1~1.0 mD)和超致密(k=0.1~0.01 mD)的砂岩和页岩气藏。评价气井水力压裂的效果,除气井的产量外,还有通过水力压裂... 水力压裂技术的实施,是提高井产能和增加气藏采收率的重要手段。目前在国际上天然气的开采,主要集中于深层的致密气(k=0.1~1.0 mD)和超致密(k=0.1~0.01 mD)的砂岩和页岩气藏。评价气井水力压裂的效果,除气井的产量外,还有通过水力压裂形成的裂缝导流能力(kfwf)和裂缝的半长(xf)。Cinco-Ley于1981年提出的评价方法,受到国内外的高度重视和广泛的引用。然而,利用Cinco-Ley模型的评价方法,主要是利用无因次模型的典型曲线图进行拟合求解,求得kfwf、xf、k和Sf(裂缝表皮系数)的数值。然而,该技术的应用,存在人为的多解性和不确定性问题。本文基于Cinco-Ley的双线性流模型和地层线性流模型,利用SI实用单位进行解析式的推导,得到了简单实用的解析式。通过实例的应用表明,解析式是正确有效的。同时,利用弹性二相法评价了气井控制的原始地质储量(OGIP)。 展开更多
关键词 气井 水力压裂 效果 Cinco-Ley模型 应用 评价 OGIP
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Study on the effect of four kinds of raw materials in hypertonic dehydration cell model
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作者 Yuanyuan Gao Qidan Tan +3 位作者 Chencan Cao Haifeng Chen Yuying Jia Lei Liu 《日用化学工业(中英文)》 CAS 北大核心 2024年第10期1218-1226,共9页
It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The ... It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The safety mass concentrations of four raw materials were screened by detecting cell viability,and the secretion of hyaluronic acid(HA)was determined using the ELISA method.The expression of HaCaT barrier function related genes(OVOL1,EREG,TGM1,TGM2,IVL,IRF6,THBS1,CASP14)was detected at the mRNA level to explore the regulatory effect of four raw materials on these genes.The results demonstrate that pretreatment with the four kinds of raw materials could increase the cell viability after hyperosmotic dehydration,promote the secretion of HA,and improve the expression of barrier function related genes after hyperosmotic dehydration,among which panthenol and Calendula officinalis L.are better.The results show that the four raw materials have a certain protective effect on the hyperosmotic dehydration cell model,which provides data support for its application in cosmetics. 展开更多
关键词 hypertonic dehydration cell model protective effect barrier repair efficacy evaluation of cosmetics soothing ingredients
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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage 被引量:1
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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融合InSAR与机器学习的滑坡易发性评价 被引量:3
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作者 贾应 吴彩燕 +5 位作者 王立娟 应欣翰 蒙齐 袁怡 廖军 马世乾 《大地测量与地球动力学》 北大核心 2025年第3期231-238,共8页
综合运用InSAR和机器学习技术,对四川省金阳县进行滑坡易发性评价。通过解译滑坡更新数据集,基于12个评价因子,在Python环境下使用随机森林(RF)、支持向量机(SVM)和极端梯度提升(XGBoost)3种模型进行训练,完成滑坡易发性制图,并采用ROC... 综合运用InSAR和机器学习技术,对四川省金阳县进行滑坡易发性评价。通过解译滑坡更新数据集,基于12个评价因子,在Python环境下使用随机森林(RF)、支持向量机(SVM)和极端梯度提升(XGBoost)3种模型进行训练,完成滑坡易发性制图,并采用ROC曲线等验证模型预测性能。对负样本进行优化,使用机器学习得到样本优化后的滑坡易发性评价结果,并利用地表LOS向形变速率对其进行更新。结果表明,3种机器学习模型均具有较好的分区效果,XGBoost模型制图效果最佳,样本优化后模型精度最高,AUC值达到0.95。通过SBAS-InSAR技术获取地表形变速率可以减少分区错误,同时赋予滑坡易发性评价结果时效性。 展开更多
关键词 滑坡易发性评价 SBAS-inSAR 机器学习 样本优化
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Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
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作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
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融合SBAS-InSAR形变与机器学习模型的滑坡易发性评价
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作者 李文东 叶禹 +2 位作者 李霞 魏伟 辛存林 《测绘通报》 北大核心 2025年第7期126-131,146,共7页
本文综合运用InSAR和机器学习技术,对甘肃省夏河县北部滑坡重点区进行易发性评价,将SBAS-InSAR获取的形变信息作为动态评价因子参与到11个静态因子中,使用随机森林(RF)、逻辑回归(LR)、极端梯度提示(XGBoost)3种模型进行易发性评价,并... 本文综合运用InSAR和机器学习技术,对甘肃省夏河县北部滑坡重点区进行易发性评价,将SBAS-InSAR获取的形变信息作为动态评价因子参与到11个静态因子中,使用随机森林(RF)、逻辑回归(LR)、极端梯度提示(XGBoost)3种模型进行易发性评价,并对其评价性能进行对比分析。结果发现,3种评价模型中,XGBoost模型性能最佳,且加入形变量后的XGBoos模型评价精度高于仅使用静态因子的XGBoost模型,其综合性能指标AUC值达0.93,召回率、准确率、F1分数分别达0.896、0.894、0.898。因此,将SBAS-InSAR技术获取的地表形变量作为滑坡易发性评价因子,可以提高模型预测的准确性,并能增加评价的实效性。 展开更多
关键词 滑坡易发性评价 机器学习 SBAS-inSAR 评价因子 夏河县
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Prediction Method of Polar Navigation Window Period Based on Risk Evaluation
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作者 JIANG Jia−qi SHI Gui−jie WANG De−yu 《船舶力学》 北大核心 2025年第6期986-999,共14页
With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation wind... With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation window period is crucial for navigating in the Arctic route,which is of great significance to the selection of the route and the optimization of navigation.This paper introduces the establishment of a risk index system,determination of risk index weight,establishment of a risk evaluation model,and prediction algorithm for the window period.In addition,data sources of both environmental factors and ship factors are introducted,and their shortcomings are analyzed,followed by introduction of various methods involved in window prediction and analysis of their advantages and disadvantages.The quantitative risk evaluation and window period algorithm can provide a reference for the research of polar navigation window period prediction. 展开更多
关键词 window period risk evaluation polar navigation risk index
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Evaluation of restoration effects for city walls based on terahertz-infrared integrated technology
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作者 MENG Tian-hua ZHAO Guo-zhong +3 位作者 XU Shi-xiang ZHANG Hai-jiao LI Bang-quan HU Wei-dong 《中国光学(中英文)》 北大核心 2025年第4期954-967,共14页
To scientifically evaluate the restoration performance of ancient city walls,Terahertz time-domain spectroscopy(THz-TDS)and infrared thermal imaging technology were applied to assess the Desheng Fortress(Ming Dynasty)... To scientifically evaluate the restoration performance of ancient city walls,Terahertz time-domain spectroscopy(THz-TDS)and infrared thermal imaging technology were applied to assess the Desheng Fortress(Ming Dynasty).Three representative sections were examined:adobe brick masonry repaired(Area 1),well-preserved original(Area 2),and layer-by-layer ramming repaired(Area 3).THz spectral data revealed significant differences between Area 1(time delay:3.72 ps;refractive index:2.224)and Area 2(time delay:3.02 ps;refractive index:2.107),while Area 3(time delay:3.12 ps;refractive index:2.098)demonstrated nearly identical THz spectral data to Area 2.Infrared thermal imaging also showed that the Area 3 restored by layer-by-layer ramming exhibited greater uniformity with fewer instances of cracks,capillary phenomena,or biological diseases.The proposed point-surface integrated evaluation methodology synergistically combines infrared thermography mapping of heritage surfaces with THz spectral datasets acquired through in-situ micro-sampling,enabling quantitative restoration assessment and providing a novel approach for scientifically validating traditional conservation techniques. 展开更多
关键词 nondestructive testing cultural relic restoration performance evaluation high sensitivity
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Performance analysis of scramjet including magnetohydrodynamic power generation after combustor
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作者 LIU Chenyuan WU Shaoxun MENG Hao 《推进技术》 北大核心 2025年第8期15-28,共14页
To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a b... To investigate the overall performance of reverse energy bypass scramjet,firstly a variable spe⁃cific heat method combined with a chemical balance calculation module for combustion products were used to es⁃tablish a benchmark scramjet performance evaluation model.Based on the test data of typical flying point of Mach 7 with the altitude of 29 km,the reliability of the model was verified.The deviations of parameters such as the to⁃tal pressure loss of combustor between the model and the test data were analyzed.Furtherly,an analytical method for post-combustion magnetohydrodynamic power generation was established;by embedding the above method into the overall performance evaluation model,performance prediction considering the power generation effect was realized.Finally,based on the above model,variety regulations of the inlet and the outlet parameters of the power generation channel and performance parameters including the engine specific impulse and the unit thrust under different enthalpy extraction ratios and load factors were analyzed.It could be concluded that the model can reliably predict the variations of key parameters.As the value of the load factor increases,the value of the conduc⁃tivity required to reach the specified enthalpy extraction ratio first decreases and then increases,which is approxi⁃mately parabolic.In order to reduce the demand for the gas conductivity for MHD power generation,the load fac⁃tor should be around 0.5.When the load factor is 0.4 and the magnetic induction intensity is 2.5 T,if the enthalpy extraction ratio reaches 0.5%,the engine specific impulse performance reduces about 3.58%. 展开更多
关键词 SCRAMJET Energy bypass Magnetohydrodynamic power generation Chemical balance Performance evaluation
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FireLink:一种面向芯粒设计空间探索的评估框架
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作者 李开 曾坤 +3 位作者 荣培涛 陈志强 张甜 王永文 《计算机研究与发展》 北大核心 2025年第5期1108-1122,共15页
基于先进封装技术的芯粒(Chiplet)集成芯片在制造成本、设计效率以及专用定制等方面更具优势,是延续芯片性能增长的有效途径.设计空间探索(design space exploration,DSE)作为体系结构量化分析的重要方法,能够帮助设计者理解并权衡设计... 基于先进封装技术的芯粒(Chiplet)集成芯片在制造成本、设计效率以及专用定制等方面更具优势,是延续芯片性能增长的有效途径.设计空间探索(design space exploration,DSE)作为体系结构量化分析的重要方法,能够帮助设计者理解并权衡设计参数间的复杂关系.但是将传统的芯片体系结构DSE方法直接应用于Chiplet设计时,存在评估不全面、模拟不精确以及探索效率低下等问题,针对这些问题提出了解决方案FireLink,作为一个面向Chiplet设计空间探索的评估框架,它支持Chiplet微架构以及互连网络的建模和模拟,具备高效评估性能、功耗、面积和成本指标的能力.此外,在该框架下采用了ID3(iterative dichotomiser 3)机器学习算法进行了实验,结果显示该框架能够有效提高DSE的效率.与现有的DSE框架和方法相比,FireLink在评估全面性、建模完整性和高效性方面具有显著优势,使得设计者能够在更短时间内探索更广泛的设计空间,进而选定较优的Chiplet设计方案. 展开更多
关键词 芯粒 设计空间探索 模拟 评估 微架构
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LuoFuShan Rheumatism Plaster ameliorates s neuropathicpain in mice by suppressing TLR4/TNF-αsignaling
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作者 FU Yufang TAN Weiling +3 位作者 LI Xiaocui LIN Rongtian LIU Shuwen YE Ling 《南方医科大学学报》 北大核心 2025年第11期2285-2296,共12页
Objective To explore the therapeutic effect of LuoFuShan Rheumatism Plaster(LFS)on neuropathic pain(NP)and its molecular mechanism.Methods Mouse models of sciatic nerve chronic constriction injury(CCI)were treated wit... Objective To explore the therapeutic effect of LuoFuShan Rheumatism Plaster(LFS)on neuropathic pain(NP)and its molecular mechanism.Methods Mouse models of sciatic nerve chronic constriction injury(CCI)were treated with low,medium,and high doses(2.2,4.4,and 8.8 cm2,respectively)of LFS by topical application for 14 consecutive days.The therapeutic effects were assessed by evaluating the mechanical withdrawal threshold(MWT),paw withdrawal latency(PWL),plasma IL-6 and TNF-αlevels,and histopathology of the sciatic nerve.Network pharmacology and molecular docking were used to identify the key targets and signaling pathways.The key targets were verified by RT-qPCR and immunohistochemistry.The biosafety of LFS was evaluated by measuring the organ indices and damage indicators of the heart,liver,and kidneys.Results Compared with the CCI group,LFS dose-dependently increased MWT and PWL,reduced plasma IL-6 and TNF-αlevels,and alleviated sciatic nerve inflammation in the mouse models.Network pharmacology identified 378 bioactive compounds targeting 279 NPassociated genes enriched in TLR and TNF signaling.Molecular docking showed that quercetin and ursolic acid in LFS could stably bind to TLR4 and TNF-α.In the mouse models of sciatic nerve CCI,LFS significantly downregulated the mRNA expression levels of Tlr4 and Tnf-αin the spinal cord in a dose-dependent manner and lowered the protein expressions of TLR4 and TNF-αin the sciatic nerve.LFS treatment did not cause significant changes in the organ indices or damage indicators of the heart,liver and kidneys as compared with those in the CCI model group and sham-operated group.Conclusion LFS alleviates NP in mice by suppression of TLR4/TNF-α-mediated neuroinflammation with a good safety profile. 展开更多
关键词 LuoFuShan Rheumatism Plaster neuropathic pain TLR4/TNF-αsignaling Safety evaluation
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基于多信息融合的INFO-VMD-CNN的齿轮箱故障诊断方法
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作者 吴胜利 郑子润 邢文婷 《振动与冲击》 北大核心 2025年第13期309-316,共8页
针对齿轮箱振动信号复杂多变,导致现有的齿轮箱故障诊断方法诊断精度不高、较弱故障特征容易被噪声淹没等问题,提出了一种基于向量加权平均优化算法(weighted mean of vectors,INFO)、变分模态分解(variational mode decomposition,VMD... 针对齿轮箱振动信号复杂多变,导致现有的齿轮箱故障诊断方法诊断精度不高、较弱故障特征容易被噪声淹没等问题,提出了一种基于向量加权平均优化算法(weighted mean of vectors,INFO)、变分模态分解(variational mode decomposition,VMD)和卷积神经网络(convolutional neural network,CNN)的齿轮故障诊断方法。该方法首先采用熵权法将不同位置的振动传感器信号信息进行融合,利用INFO对VMD算法中参数进行优化,并设计一个复合评价指标作为参数优化的评价标准,使用奇异峭度差分谱的方法对敏感分量进行重构;其次,从重构的信号中提取时域、频域特征并输入到CNN模型中进行分类;最后通过Shap(Shapley additive explanations)值法对模型输入特征的重要性进行排序,分析不同特征组合对模型分类和特定故障识别的影响。在东南大学行星齿轮数据集上进行验证,结果表明,利用所提特征组合进行故障诊断,CNN模型故障诊断准确率为98.24%,高于其他特征组合,为行星齿轮箱的故障诊断提供了一组有效的特征指标。 展开更多
关键词 行星齿轮箱故障诊断 向量加权平均算法(inFO) 奇异峭度差分谱 卷积神经网络(CNN) 评价指标 Shap值法
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Evaluation of transgenic cotton lines expressing an insecticidal fern protein against whitefly,Bemisia tabaci(Gennadius)
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作者 KUMAR Rishi NAGRARE V.S. +14 位作者 SHAH Vivek SINGH Satnam PANDHER Suneet SINGH Satpal VERMA S.K. PAUL Debashis RATHORE Pankaj SHUKLA Anoop Kumar SINGH Mithlesh Kumar SAURABH Sharad KUMAR Harish KAUR Rupinderjeet SINGH Pradhyumna Kumar WAGHMARE V.N. PRASAD Y.G. 《Journal of Cotton Research》 2025年第2期163-177,共15页
Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with des... Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with desirable traits that wouldn’t be possible through conventional breeding methods.Transgenic crops have been developed for various traits globally.Whitefly,Bemisia tabaci(Gennadius)is one of the major sucking pests of cotton that cause significant damage to the cotton production.To combat whitefly infestations,researchers have developed four transgenic cotton lines expressing the fern protein.And those transgenic lines need to be evaluated for their performance against the target pest—whitefly.The evaluation was designed as controlled trials in polyhouse or muslin cloth cages under open-choice and no-choice conditions by comparing four transgenic cotton lines(A,B,C,and D)with three control groups,including untransformed cotton plants with a same genetic background of the transgenic line,conventionally bred whitefly-resistant cotton,and whitefly-susceptible cotton.In order to study the generational effect,the evaluation also involved studies on whitefly development in laboratory,muslin cloth cage,and polyhouse conditions.Results Both open-choice and no-choice experiments had shown that all the four transgenic cotton lines(A,B,C,and D)expressing the fern protein reduced adult whitefly numbers significantly compared with the control lines,except for the no-choice conditions in 2021,where the transgenic line C was non-significant different from the resistant control line.Notably,the nymphal population on the resistant control line was relatively low and nonsignificant different from the transgenic line C in 2021;and the transgenic lines A and C in 2022 under open-choice conditions.Under no-choice condition,the nymphal counts in the resistant control line was non-significant different from transgenic lines C and D in 2021;and transgenic line D in 2022.All transgenic lines showed significant decrease in egg hatching in 2021 and nymphal development in 2022,except for the transgenic line C which had no significant different in the nymphal development comparing with non-transgenic control lines in 2022.Adult emergence rates in both years of evaluation showed significant decrease in transgenic lines A and B comparing with the control lines.Additionally,the results showed a significant reduction in cotton leaf curl disease and sooty mold development in all the four transgenic lines compared with susceptible control under open-choice conditions,indicating potential benefits of transgenic lines beyond direct effect on whitefly control.Furthermore,the research explored the generational effects of the fern protein on whitefly which revealed the lowest fecundity in the transgenic line C across F0,F1 and F3 generations,lower egg hatching in F1 and F2 generations in transgenic lines A and B,shorter nymphal duration in F1 and F2 generations in transgenic line B,and the least total adult emergence in the transgenic line C in F0 and F3 generations.Conclusions These findings suggest that the transgenic cotton lines expressing fern protein disrupts whitefly populations and the life cycle to a certain extent.However,results are not consistent over generations and years of study,indicating these transgenic lines were not superior over control lines and need to be improved in future breeding. 展开更多
关键词 EVALUATION Fern protein Transgenic cotton lines WHITEFLY
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Brittleness evaluation of gas-bearing coal based on statistical damage constitution model and energy evolution mechanism
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作者 XUE Yi WANG Lin-chao +5 位作者 LIU Yong RANJITH P G CAO Zheng-zheng SHI Xu-yang GAO Feng KONG Hai-ling 《Journal of Central South University》 2025年第2期566-581,共16页
Accurate assessment of coal brittleness is crucial in the design of coal seam drilling and underground coal mining operations.This study proposes a method for evaluating the brittleness of gas-bearing coal based on a ... Accurate assessment of coal brittleness is crucial in the design of coal seam drilling and underground coal mining operations.This study proposes a method for evaluating the brittleness of gas-bearing coal based on a statistical damage constitutive model and energy evolution mechanisms.Initially,integrating the principle of effective stress and the Hoek-Brown criterion,a statistical damage constitutive model for gas-bearing coal is established and validated through triaxial compression tests under different gas pressures to verify its accuracy and applicability.Subsequently,employing energy evolution mechanism,two energy characteristic parameters(elastic energy proportion and dissipated energy proportion)are analyzed.Based on the damage stress thresholds,the damage evolution characteristics of gas bearing coal were explored.Finally,by integrating energy characteristic parameters with damage parameters,a novel brittleness index is proposed.The results demonstrate that the theoretical curves derived from the statistical damage constitutive model closely align with the test curves,accurately reflecting the stress−strain characteristics of gas-bearing coal and revealing the stress drop and softening characteristics of coal in the post-peak stage.The shape parameter and scale parameter represent the brittleness and macroscopic strength of the coal,respectively.As gas pressure increases from 1 to 5 MPa,the shape parameter and the scale parameter decrease by 22.18%and 60.45%,respectively,indicating a reduction in both brittleness and strength of the coal.Parameters such as maximum damage rate and peak elastic energy storage limit positively correlate with coal brittleness.The brittleness index effectively captures the brittleness characteristics and reveals a decrease in brittleness and an increase in sensitivity to plastic deformation under higher gas pressure conditions. 展开更多
关键词 gas pressure statistical damage constitutive model energy evolution mechanism brittleness evaluation gas bearing coal
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基于ACGME核心能力的Milestones 2.0评估系统在全科住院医师规范化培训中的应用效果研究
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作者 杜雪晴 程瑞杰 +6 位作者 徐梦丹 姚玉婷 蒋筠 梁艳艳 刘丽燕 沈华 楼俪泓 《中国全科医学》 北大核心 2025年第28期3489-3494,共6页
背景随着我国医疗卫生事业的发展,全科作为一门新兴学科,被越来越多人所熟悉。住院医师规范化培训(以下简称住培)是医学生成为医生的必经之路。然而,全科住培在很多方面与传统学科有很大不同。因此,全科住培教育体系亟须完善。目的应用M... 背景随着我国医疗卫生事业的发展,全科作为一门新兴学科,被越来越多人所熟悉。住院医师规范化培训(以下简称住培)是医学生成为医生的必经之路。然而,全科住培在很多方面与传统学科有很大不同。因此,全科住培教育体系亟须完善。目的应用Milestones 2.0评估系统对在培全科住院医师进行自评和他评,并探讨该评估系统在全科住培中的应用效果。方法选取2023年9月上海交通大学医学院附属第一人民医院33名在培全科住院医师作为研究对象,按住培年限分为一年级、二年级和三年级组。采用研究团队结合美国毕业后医学教育认证委员会(ACGME)标准和实际情况修订的Milestones 2.0评估系统,对住院医师六大核心能力(患者照顾、医学知识、基于系统的实践、基于实践的学习和改进、专业精神、人际交往技巧)的19个二级指标进行1~9分的量化评价。通过电子问卷形式收集住院医师自评及相应带教导师他评数据,比较不同年级住院医师的能力表现差异、住院医师自评与导师他评的差异,以及不同学历者的评估结果差异。结果不同年级组在培全科住院医师自评Milestones 2.0评估系统的患者照顾、医学知识、基于系统的实践、基于实践的学习和改进、专业精神、人际交往技巧维度得分比较,差异均有统计学意义(P<0.001)。在培全科住院医师自评与他评Milestones 2.0评估系统的二级指标“循证医学和有依据的医学实践”得分比较,差异有统计学意义(P=0.040);本科生与四证合一的在培全科住院医师自评Milestones 2.0评估系统的医学知识维度得分比较,差异有统计学意义(P<0.05)。结论Milestones 2.0评估系统是一种较为客观且综合的评估方法,对住院医师的下一步培训计划有着重要的参考价值。通过此评估系统对全科住院医师进行能力评估,强调培养过程的互动与反馈,可以更好地提高住院医师的整体专业能力和道德素养,推进国家医疗卫生事业的高质量发展。 展开更多
关键词 全科医学 住院医师规范化培训 Milestones系统 ACGME核心能力
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基于Stacking集成机器学习模型的川西重大交通干线地质灾害易发性评价 被引量:1
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作者 吴逢涛 杨志全 赵旭光 《科学技术与工程》 北大核心 2025年第13期5340-5350,共11页
川西地区地形复杂多变,地质构造活跃,致使交通干线的建设与维护面临着地质灾害频发的挑战。集成学习算法能优化地质灾害易发性评估中算法的不足,提升模型的精度,在地质灾害易发性评估中具有显著优势。以沿江高速为例,选取坡度、起伏度... 川西地区地形复杂多变,地质构造活跃,致使交通干线的建设与维护面临着地质灾害频发的挑战。集成学习算法能优化地质灾害易发性评估中算法的不足,提升模型的精度,在地质灾害易发性评估中具有显著优势。以沿江高速为例,选取坡度、起伏度等12个特征变量构建地质灾害易发性评价体系,比较分析Stacking集成算法与单一算法建模的预测性能,探讨了沿江高速地质灾害的主控因素,并验证了模型的实用性。结果表明:沿江高速沿线地质灾害高和极高易发区占比分别为18.21%和9.85%,集中分布在雷波段和金阳段;Stacking集成模型受试者操作特征(receiver operating characteristics, ROC)曲线和精确率-召回率(precision-recall,P-R)曲线的曲线下的面积(area under curve, AUC)均达到0.89,F_(1)分数也达到0.84,显著高于3个单一机器学习模型的ROC曲线的AUC(0.84~0.86)、P-R曲线的AUC(0.81~0.85)和F_(1)分数(0.78~0.79),比单一机器学习算法有更好的预测性能;沿江高速地质灾害的发育受地形地貌因素控制;新增灾害点位于模型中的极高易发区,印证了Stacking模型的精确度和可靠性。 展开更多
关键词 地质灾害 机器学习 易发性评价 高速公路 预测精度
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基于S-CAD的意大利家具“Transizione 4.0计划”评估与启示
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作者 郭谌达 王志锋 《林产工业》 北大核心 2025年第5期77-83,共7页
具有全球影响力的意大利家具设计产业是学界和行业界共同关注的热点,但从政策视角切入的研究相对较少。以意大利重要政策“Transizione 4.0计划”为研究对象,首次引入S-CAD评估方法,通过分析,评估该政策的效应、效率、可行性,为相关领... 具有全球影响力的意大利家具设计产业是学界和行业界共同关注的热点,但从政策视角切入的研究相对较少。以意大利重要政策“Transizione 4.0计划”为研究对象,首次引入S-CAD评估方法,通过分析,评估该政策的效应、效率、可行性,为相关领域提供意大利家具设计产业发展的政策解读。创新之处在于应用了能够融合技术理性与政治智慧的新评估方法,可为我国相关政策制定提供参考,并为政策评估工具提供支撑。 展开更多
关键词 S-CAD政策评估方法 意大利 效应 效率 可行性
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