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Correlation, Regression and Path Analyses of Seed Yield Components in <i>Crambe abyssinica</i>, a Promising Industrial Oil Crop
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作者 Banglian Huang Yiming Yang +5 位作者 Tingting Luo Shu Wu Xuezhu Du Detian Cai Eibertus N. van Loo Bangquan Huang 《American Journal of Plant Sciences》 2013年第1期42-47,共6页
In the present study correlation, regression and path analyses were carried out to decide correlations among the agro- nomic traits and their contributions to seed yield per plant in Crambe abyssinica. Partial correla... In the present study correlation, regression and path analyses were carried out to decide correlations among the agro- nomic traits and their contributions to seed yield per plant in Crambe abyssinica. Partial correlation analysis indicated that plant height (X1) was significantly correlated with branching height and the number of first branches (P 2) was significantly correlated with pod number of primary inflorescence (P 3) was significantly correlated with number of secondary branches (P -grain weight (P 4) was significantly correlated with seed yield per plant (P 7) was significantly correlated with seed yield per plant (P -grain weight (P -grain weight (X8) was significantly correlated with seed yield per plant (P -grain weight contributed significantly to seed yield per plant at P 7) and 1000-grain weight (X8) to seed yield per plant (Y) is Y = 0.006 X7 + 1.222 X8 - 7.191. The path coefficient of pod number per plant to seed yield per plant was 0.967 and that of 1000-grain weight was 0.194. The determination coefficient of pod number per plant and 1000-grain weight to seed yield per plant was 0.983 and the determination coefficient of other agronomic traits was 0.130. Coefficient of variance indicated that the length of primary inflorescence showed the greatest variation, followed by seed yield per plant, pod number per plant, number of secondary branches, branching height, pod number of primary inflorescence, number of first branches, seed yield per plot, 1000-grain weight and plant height. It was suggested that seed yield per plant in Crambe might be improved by increasing the pod number per plant through selection or cultivation, but the negative correlation between pod number per plant and 1000-grain weight also needs to be considered. 展开更多
关键词 CORRELATION Crambe abyssinica path Analysis Regression SEED YIELD components
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Principal-component estimates of the Kuroshio Current axis and path based on the mathematical verification between satellite altimeter and drifting buoy data 被引量:2
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作者 Zhanpeng Zhuang Zhenli Hui +2 位作者 Guangbing Yang Xinhua Zhao Yeli Yuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第1期14-24,共11页
We used satellite altimetry data to investigate the Kuroshio Current because of the higher resolution and wider range of observations. In previous studies, satellite absolute geostrophic velocities were used to study ... We used satellite altimetry data to investigate the Kuroshio Current because of the higher resolution and wider range of observations. In previous studies, satellite absolute geostrophic velocities were used to study the spatiotemporal variability of the sea surface velocity field along the current, and extraction methods were employed to detect the Kuroshio axes and paths. However, sea surface absolute geostrophic velocity estimated from absolute dynamic topography should be regarded as the geostrophic component of the actual surface velocity, which cannot represent a sea surface current accurately. In this study, mathematical verification between the climatic absolute geostrophic and bin-averaged drifting buoy velocity was established and then adopted to correct the satellite absolute geostrophic velocities. There were some differences in the characteristics between satellite geostrophic and drifting buoy velocities. As a result, the corrected satellite absolute geostrophic velocities were used to detect the Kuroshio axis and path based on a principal-component detection scheme. The results showed that the detection of the Kuroshio axes and paths from corrected absolute geostrophic velocities performed better than those from satellite absolute geostrophic velocities and surface current estimations. The corrected satellite absolute geostrophic velocity may therefore contribute to more precise day-to-day detection of the Kuroshio Current axis and path. 展开更多
关键词 Kuroshio axis detection Kuroshio path detection mathematical verification satellite absolute geostrophic velocity principal-component detection
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A Fuzzy Clustering Algorithm Based on Multipath Component Trajectory for Millimeter Wave Radio Channels
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作者 Fei Du Yu Zhang +5 位作者 Qingliang Li Xinyue Zhang Bo Zhu Zihao Fu Suiyan Geng Xiongwen Zhao 《China Communications》 SCIE CSCD 2022年第11期99-111,共13页
Time-varying channel modeling plays an important role for many applications in time-variant scenarios,while most clustering algorithms focus on static channels and cannot accurately model the channel time-evolution pr... Time-varying channel modeling plays an important role for many applications in time-variant scenarios,while most clustering algorithms focus on static channels and cannot accurately model the channel time-evolution properties.In this paper,a fuzzy clustering algorithm based on multipath component(MPC)trajectory is proposed.Firstly,both the distance and velocity similarities of the MPCs in different snapshots are taken into account to track the MPC trajectory,in which the fuzzy scheme and a kernel function are used to calculate the distance and velocity similarities,respectively.Secondly,a fuzzy MPC trajectory clustering algorithm is proposed to cluster the MPCs in multiple snapshots.The MPCs in a snapshot are clustered according to the membership,which is defined as the probability that a MPC belongs to different clusters.Finally,time-varying channels at 28 GHz are simulated to validate the performance of our proposed algorithm.The results show that our proposed algorithm is able to accurately identify the clusters in time-varying channels compared with the existing clustering algorithms. 展开更多
关键词 channel modeling TIME-VARYING clustering multiple path component MPC trajectory 6G
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Effect of Loading Paths on Hydroforming Tubular Square Components
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作者 Hongyang LI Shijian YUAN +3 位作者 Kun DAI Lihui LANG Xiaosong WANG Zhubin HE and Zhongren WANG School of Materials Science and Engineering, Harbin institute of Technology, Harbin 150001, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第1期158-,共1页
The influence of loading path on tube hydroforming process is discussed in this paper with finiteelement simulation. Four different loading paths are utilized in simulating the forming process of square tubular compo... The influence of loading path on tube hydroforming process is discussed in this paper with finiteelement simulation. Four different loading paths are utilized in simulating the forming process of square tubular component with hydroforming and the result of different loading path is presented. Among the result. the thickness distribution of bilinear loading path is the most uniform one. It shows that the increase of punch displacement in the stage of high pressure is beneficial to the forming of component for optimized Stress condition. 展开更多
关键词 Effect of Loading paths on Hydroforming Tubular Square components
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Research on the Correlation between Meteorological Factors and Flue-cured Tobacco Chemical Components in Different Altitudes of Lincang Region 被引量:2
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作者 王娜 赵正雄 +2 位作者 白羽祥 李世琛 陈泽 《Agricultural Science & Technology》 CAS 2015年第3期593-599,共7页
In this study, the relationship between major meteorological factors and tobacco chemical components in different altitudes of Yongde County, Lincang Region of Yunnan Province was studied using correlation analysis an... In this study, the relationship between major meteorological factors and tobacco chemical components in different altitudes of Yongde County, Lincang Region of Yunnan Province was studied using correlation analysis and path analysis methods.The results showed that there was a difference on meteorological factors in different altitudes, causing different impacts on chemical components of flue-cured tobacco; contents of nicotine and total nitrogen decreased with the rising of altitude, conversely, total sugar and reducing sugar contents increased with the rising trend of altitude, and the differences on the contents of potassium (K) and chlorine(CI), and the ratio of K to CI in different altitudes were not significant, at the altitude of 1 250-1 450 m, each chemical component indicator was better. The correlation between main meteorological factors and conventional chemical components of tobacco leaves was as follows: contents of reducing sugar and total sugar increased with the increase of rainfall and relative humidity, and decreased with the increase of sunshine duration; nicotine content increased with the increase of accumulated temperature and sunshine duration; total nitrogen (N) content increased with the increase of daily mean temperature and accumulated temperature; sugar-alkali ratio increased with the increase of rainfall. Path analysis showed that the direct effect of sunshine duration on reducing sugar and total sugar of tobacco leaves was faint, but the indirect effect was obvious; meanwhile, the direct and indirect effects of it on nicotine and total N were the greatest. 展开更多
关键词 ALTITUDE Meteorological factors . Chemical components Correlation anal- ysis path analysis
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Evaluation of Chinese Cabbage Sensory Quality and Its Relationship with Contents of Main Nutrient Components 被引量:1
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作者 龚振平 于拴仓 +5 位作者 张凤兰 余阳俊 赵岫云 张德双 汪维红 苏同兵 《Agricultural Science & Technology》 CAS 2016年第7期1592-1596,共5页
In order to establish a comprehensive evaluation system for quality of Chinese cabbage, 28 Chinese cabbage cultivars or inbreeds were selected as ex- perimental materials to identify the raw and cooked taste and deter... In order to establish a comprehensive evaluation system for quality of Chinese cabbage, 28 Chinese cabbage cultivars or inbreeds were selected as ex- perimental materials to identify the raw and cooked taste and determine the nutrient component contents, and the subjective factors (taste) and objective factors (nutrient component contents) influencing the sensory quality of Chinese cabbage were ana- lyzed by multiple regression and path analysis. The results showed that two regres- sion equations were obtained: yr (raw quality)=0.310 3+0.254 0xl (juiciness)+0.176 2 x2 (sweetness)+0.221 6x3 (crispness)+0.319 9x4 (flavor); Yc (cooked quality)=0.204 4+ 0.250 9 xs (residue)+0.246 9x6 (cooked sweetness)+0.182 5x7 (softness)+0.323 lx8 (cooked flavor). The path analysis results showed that among the sensory indices, the total coefficients of sweetness and juiciness were 0.445 3 and 0.427 6, respec- tively. It indicated they were the main factors affecting the raw quality of Chinese cab- bage, followed by flavor and crispness. Sweetness, with total coefficient of 0.515 2, showed the greatest effect on the cooked quality of Chinese cabbage, followed by residue, cooked flavor and softness. The effects of nutrient component contents on the sensory quality of Chinese cabbage were further analyzed, and the regression equa- tions were obtained: y, =-32.192 0+0.389 3xw (moisture content)+1.169 8x~ (soluble sugar content); Yc = 7.497 1+0.732 6xs - 5.668 8x, (organic acid content)-2.176 3x~ (crude fiber content). The standardized regression coefficients of soluble sugar con- tent were all highest with the value of 0.580 7 in the raw quality regression equa- tion and 0.325 0 in the cooked quality one, indicating that among the six nutrient components, the soluble sugar content was the main factor affecting both raw and cooked quality of Chinese cabbage. This study will provide certain basis for quality evaluation, selection and breeding of high-quality Chinese cabbage. 展开更多
关键词 Chinese cabbage Sensory quality Nutritional component path analysis Regression analysis
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Correlation Analysis Between Yield Components and Yield Per Plant of Double-low Hybrid Rapeseed 被引量:1
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作者 张锦芳 周贤琼 +2 位作者 蒲晓斌 李浩杰 蒋梁材 《Agricultural Science & Technology》 CAS 2008年第6期82-83,117,共3页
[Objective] The experiment aimed to study the relation between yield components and yield per plant of double-low hybrid rapeseed and provide reference for breaking yield limitation of rapeseed and culturing new doubl... [Objective] The experiment aimed to study the relation between yield components and yield per plant of double-low hybrid rapeseed and provide reference for breaking yield limitation of rapeseed and culturing new double-low hybrid rapeseed variety. [Method]The yield components and yield per plant of two cross combination of double-low hybrid rapeseed (B02, D04) and Shuza 6 were correlatively analyzed and compared, besides, the path analysis was also carried on to them. [Result] Among B02, D04 and Shuza No.6, effective pod number per plant and seeds per silique, seeds per pod and 1 000-grain weight were all negative correlation. In high yield hybrid, pod number per plant, seeds per pod had more impaction on yield per plant than 1 000-grain weight and the difference was at 0.01 significant level. In the control variety Shuza No.6, the impactions of pod number per plant and seeds per pod on yield per plant were bigger than that of 1 000-grain weight on yield per plant, however, the difference was not significant. [Conclusion] The improvement of effective pod number per plant was an important aim of breeding work of double low rapeseed breeding in Sichuan ecological region. 展开更多
关键词 Double low rapeseed Yield components Yield per plant Correlation analysis path analysis
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Relationship Among Yield Components and Selection Criteria for Yield Improvement in Early Rapeseed (Brassica napus L.) 被引量:4
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作者 LU Guang-yuan ZHANG Fang +4 位作者 ZHENG Pu-ying CHENG Yong LIU Feng-lan FU Gui-ping ZHANG Xue-kun 《Agricultural Sciences in China》 CAS CSCD 2011年第7期997-1003,共7页
The objective of this study was to determine the relationship between seed yield and other important agronomic traits of early-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson's corre... The objective of this study was to determine the relationship between seed yield and other important agronomic traits of early-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson's correlation coefficient as well as to estimate direct and indirect effects of specific yield component traits on seed yield via path analysis. Nineteen rapeseed genotypes were grown at ten environments in South China during 2008-2009 and 12 characters were evaluated. Analysis of variance showed that environment had a significant impact on all characters. For most characters the genotype by environment interaction was weak and not statistically significant. Simple correlation analysis indicated that the number of primary branches (PB), number of pods on the main raceme (PR), and number of seeds per pod made significant contributions to seed yield per plant (SYP), while 1 000-seed weight was negatively correlated with SYP (r=-0.485, P0.05). Furthermore, number of pods per plant (PP), PB, and PR had the greatest direct effects on SYP. In addition, PP and PB were the best indicators to predict seed yield in stepwise regression analysis. Finally, yield component differences between early- and medium-maturity varieties were compared; this showed that to improve the seed yield of early varieties, more emphasis should be given to increase PP, PB, and PR, and reduce plant height and shortening of growth duration in breeding practice. 展开更多
关键词 Brassica napus L. early maturity yield component path analysis
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贵州特色甘蓝型油菜杂交组合农艺性状分析及选育
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作者 徐红平 李杨 +5 位作者 朱晶晶 覃焕 黄莎 张瑞茂 李超 李继军 《中国油料作物学报》 北大核心 2026年第1期93-103,共11页
油菜是保障我国食用油安全的重要作物,单产提升缓慢使产业发展陷入瓶颈。为深入解析主要农艺性状与单株产量之间的内在关系,明确甘蓝型油菜单株产量形成的关键影响因子,本研究以80份甘蓝型油菜新组合为材料,系统评价了农艺性状与产量表... 油菜是保障我国食用油安全的重要作物,单产提升缓慢使产业发展陷入瓶颈。为深入解析主要农艺性状与单株产量之间的内在关系,明确甘蓝型油菜单株产量形成的关键影响因子,本研究以80份甘蓝型油菜新组合为材料,系统评价了农艺性状与产量表现;综合运用相关性分析、通径分析和主成分分析等方法,筛选出单株产量构成的关键性状及综合性状优良的组合。结果表明,单株产量与株高、生物产量及单株有效角果数呈显著正相关,而每角粒数与角果数、千粒重之间存在显著负相关。通径分析表明,生物产量是单株经济产量形成的核心驱动因子,其直接通径系数达0.81,与株高、角果数等性状产生显著的间接效应。主成分分析提取的4个主成分累计贡献率达79.86%,为不同育种目标提供了理论依据。通过对80个甘蓝型油菜组合的系统评价和分析,筛选出4个综合性状优良的组合(2007、2008、2009、2027)。经两年试验验证,进一步验证了上述对比分析结论的可靠性,为组合的合理选用提供了稳定依据。 展开更多
关键词 油菜组合 相关性分析 通径分析 主成分分析
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基于双标图和通径系数评价高产大果花生‘郑农花15号’ 被引量:1
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作者 于沐 朱桢桢 +5 位作者 胡延岭 杨海棠 李盼 刘软枝 石彦召 韩艳红 《分子植物育种》 北大核心 2026年第1期139-146,共8页
为指导大果花生高产选育和应用推广,对其数量性状进行综合评价,本研究利用GGE-biplot工具对高产大果花生品种‘郑农花15号’的荚果产量、百果重、出仁率和单株饱果数的丰产性、稳定性和适应性进行检测,并分析其产量构成,用R语言分析‘... 为指导大果花生高产选育和应用推广,对其数量性状进行综合评价,本研究利用GGE-biplot工具对高产大果花生品种‘郑农花15号’的荚果产量、百果重、出仁率和单株饱果数的丰产性、稳定性和适应性进行检测,并分析其产量构成,用R语言分析‘郑农花15号’的农艺性状和荚果产量的相关性及通径系数。结果表明:‘郑农花15号’丰产稳产性好,百果重高且表型较稳定,出仁率高但表型值不稳定,单株饱果数表型值不稳定;变异系数方面,出仁率最小,单株结果数最大;单株果数、总分枝数、结果枝数与荚果产量呈极显著正相关,主茎高、侧枝长、百果重、百仁重、出仁率与荚果产量显著正相关;9个农艺性状对荚果产量的直接通径系数排序为:侧枝长>结果枝数>百果重>出仁率>饱果率>单株结果数>百仁重>总分枝数>主茎高。综上所述,‘郑农花15号’综合表现良好,属于稳定性、丰产性、适应性均较好的品种,适宜郑州、开封、石家庄、密云及相似生态区大面积推广种植,生产时可注重侧枝长和结果枝数的选择,本研究为高产大果花生的品种选育和评价推广提供依据,并对其他作物数量性状的综合评价具有一定的参考价值。 展开更多
关键词 郑农花15号 GGE双标图 产量构成 农艺性状 通径分析
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荒漠光伏电站人工植被恢复对土壤有机碳组分的影响
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作者 翟波 党晓宏 +2 位作者 刘湘杰 暴向平 樊才睿 《中国农业大学学报》 北大核心 2026年第1期180-192,共13页
为厘清荒漠地区光伏电站人工植被恢复对土壤有机碳系统所产生的影响和扰动机理,以库布齐沙漠光伏电站为研究区域。采用野外观测法对光伏阵列内不同位置(光伏板前、板间、板后)的杂花苜蓿和糜子种群特征(盖度、密度、高度、生物量)进行量... 为厘清荒漠地区光伏电站人工植被恢复对土壤有机碳系统所产生的影响和扰动机理,以库布齐沙漠光伏电站为研究区域。采用野外观测法对光伏阵列内不同位置(光伏板前、板间、板后)的杂花苜蓿和糜子种群特征(盖度、密度、高度、生物量)进行量化,对植被调查样点及板下和对照处的不同土层土壤含水量体积浓度和有机碳组分(有机碳、易氧化有机碳、可溶性有机碳、热水溶性有机碳、水溶解性有机碳、微生物量碳)进行室内测定,并通过相关性分析和通径分析得出土壤水分环境和种群特征对土壤有机碳组分再分配的贡献率。结果表明:1)光伏阵列内不同位置的杂花苜蓿和糜子的种群特征产生显著差异。板间与板前的各指标均具有显著性差异(P<0.05),板间杂花苜蓿生物量较板前和板后分别增加了154.20%和79.77%。2)土壤有机碳组分对光伏阵列内不同位置的反馈呈现出一定规律性,各位置表层土壤有机碳组分含量整体大于深层土壤。板间0—5 cm土层有机碳含量相比板前、板后、板下和CK分别增加了24.30%、44.74%、59.15%和35.37%。深层土壤有机碳组分在板间和板后2个位置含量较高,其中板间土壤有机碳组分含量最高。3)光伏阵列内板间和板后的土壤含水量体积浓度相比其他位置优势明显。土壤含水量体积浓度的变化对土壤有机碳组分产生了促进作用,其与土壤微生物量碳的相关系数为0.928。4)土壤有机碳和人工植被种群特征的通径分析结果表明,糜子的密度和杂花苜蓿的高度是影响板前土壤有机碳的关键因素;糜子生物量是影响板间土壤有机碳的重要因子;杂花苜蓿的生物量对板后土壤有机碳含量增加的贡献率最高。综上,光伏阵列通过对杂花苜蓿+糜子人工植被生长进行调控,促进了板间和板后的种群生物量,提升了土壤含水量的同时显著增加了电站内土壤有机碳组分含量。 展开更多
关键词 荒漠光伏电站 植被恢复 土壤有机碳组分 土壤含水量体积浓度 通径分析
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2006—2022年北方白菜型冬油菜农艺性状遗传增益分析 被引量:2
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作者 张天宇 刘丽君 +7 位作者 杨刚 武军艳 蒲媛媛 马骊 王旺田 路晓明 马愿强 孙万仓 《中国农业科学》 北大核心 2025年第11期2081-2095,共15页
【目的】依据2006—2022年81个白菜型冬油菜品种(系)在酒泉、张掖、武威、兰州、庆阳、平凉、天水和陇西等8个代表极干旱、干旱、半干旱生态区试点的试验结果,研究这些地区白菜型冬油菜农艺性状的演变,以期为北方白菜型冬油菜育种研究... 【目的】依据2006—2022年81个白菜型冬油菜品种(系)在酒泉、张掖、武威、兰州、庆阳、平凉、天水和陇西等8个代表极干旱、干旱、半干旱生态区试点的试验结果,研究这些地区白菜型冬油菜农艺性状的演变,以期为北方白菜型冬油菜育种研究与生产提供参考。【方法】参试品种(系)包括强抗寒类型和一般抗寒类型两大类型,对其主要农艺性状进行遗传增益分析、相关性分析、通径分析和主成分分析。【结果】17年间,北方白菜型冬油菜农艺性状改良效果明显,强抗寒性品种的株高、分枝部位、分枝数、单株角果数和单株产量呈逐步上升趋势,年平均增加0.87%、1.07%、0.0837%、6.09%和0.0281%,角粒数和千粒重呈下降趋势,年平均减少0.0289%和0.012%;一般抗寒性品种的株高、分枝部位、单株角果数、角粒数和单株产量呈逐步上升趋势,年平均增加2.18%、2.19%、1.27%、0.117%和0.0776%,分枝数、千粒重则呈下降趋势,年平均减少0.109%和0.00702%。相关性分析表明,北方白菜型冬油菜的单株产量和单株角果数呈极显著正相关,单株产量与农艺性状通径分析表明,强抗寒性品种对单株产量贡献最大的是单株角果数(0.961),其次为角粒数(0.365);一般抗寒性品种对单株产量贡献最大的是分枝部位(1.173),其次为单株角果数(0.544)。单株产量与气候因子的通径分析表明,强抗寒性品种受10℃积温影响较大,一般抗寒性品种受0℃负积温影响较大。主成分分析筛选出总体方差累计贡献率达78.617%的3个主成分,其中,单株角果数、分枝部位、千粒重等是造成这些品种间差异的主要因素。【结论】北方白菜型冬油菜农艺性状的遗传改良育种取得显著进展,单株产量在稳步提升;株型也得到了极大程度的改良;单株角果数是白菜型冬油菜增产的主要因素;强抗寒性品种对外界环境的适应能力强于一般抗寒性品种。 展开更多
关键词 白菜型冬油菜 农艺性状 演变规律 通径分析 主成分分析
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面向健康管理的民航发动机气路基准模型建立与验证 被引量:1
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作者 郭庆 孙正日 +2 位作者 樊俊峰 付宇 左洪福 《推进技术》 北大核心 2025年第3期215-226,共12页
针对民航发动机健康管理领域中,对气路性能诊断与预测的需求,提出了一种以通用模型为基础,结合试车数据修正的基准性能建模方法。使用大修后试车数据构建稳态性能模型,并通过Newton-Raphson算法求解发动机非线性方程组,以准确计算不同... 针对民航发动机健康管理领域中,对气路性能诊断与预测的需求,提出了一种以通用模型为基础,结合试车数据修正的基准性能建模方法。使用大修后试车数据构建稳态性能模型,并通过Newton-Raphson算法求解发动机非线性方程组,以准确计算不同工况下的特性参数。为提升模型精度,引入了一种基于折合转速的二次修正因子函数,将传统的线性修正改进为多工况点的非线性修正,确保了目标发动机特性图的精确性。利用CFM56-7B型发动机的飞机通信寻址与报告系统(Airplane Commu⁃nication Addressing and Reporting System,ACARS)报文数据,验证了所建模型的准确性。结果表明,该方法在精度上优于传统的多元线性回归发动机基线模型。 展开更多
关键词 民航发动机 健康管理 气路分析 基准建模 部件特性修正
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复杂构件缺陷机器人修复加工技术研究进展 被引量:1
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作者 朱大虎 王升哲 +2 位作者 徐子嫣 王宜丹 华林 《机械工程学报》 北大核心 2025年第11期1-22,共22页
针对交通运输、航空航天、能源国防等高端装备制造领域复杂构件表面缺陷高效高品质修复加工重大需求,对近年来以机器人为制造装备执行体的机器人修复加工技术的研究进展进行了综述。具体围绕机器人修复所涉及的缺陷视觉测量、路径决策... 针对交通运输、航空航天、能源国防等高端装备制造领域复杂构件表面缺陷高效高品质修复加工重大需求,对近年来以机器人为制造装备执行体的机器人修复加工技术的研究进展进行了综述。具体围绕机器人修复所涉及的缺陷视觉测量、路径决策规划、加工质量控制等关键技术,系统分析了国内外已公开发表的相关文献,并以汽车车身、高铁车身与发动机叶片为例,阐述了机器人缺陷修复工程应用。最后从多机器人协同、在线信息交互、动态性能监控、混合加工工艺等方面对该领域未来研究方向进行了展望。 展开更多
关键词 机器人修复加工 复杂构件 视觉测量 路径决策 质量控制
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基于多尺度融合金字塔焦点网络的接触网零部件检测 被引量:4
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作者 朱新宇 崔浩锐 宋洋 《工程科学学报》 EI 北大核心 2025年第2期315-327,共13页
作为高铁牵引供电系统的重要组成部分,接触网系统承担着向动车组传输电能的重要功能.实际工程运营表明,受弓网交互产生的持续冲击以及外部环境的影响,接触网支撑部件可能会出现“松、脱、断、裂”等缺陷,导致接触网结构可靠性下降,严重... 作为高铁牵引供电系统的重要组成部分,接触网系统承担着向动车组传输电能的重要功能.实际工程运营表明,受弓网交互产生的持续冲击以及外部环境的影响,接触网支撑部件可能会出现“松、脱、断、裂”等缺陷,导致接触网结构可靠性下降,严重影响接触网系统稳定运行.因此,及时精确定位接触网支撑部件(CSCs),对保障高铁安全运行和完善接触网检修维护策略具有重大意义.然而,CSCs的检测通常面临着零部件种类多、尺度差异大、部分零部件微小的问题.针对以上问题,本文提出一种基于多尺度融合金字塔焦点网络的接触网零部件检测算法,将平衡模块和特征金字塔模块相结合,提高对小目标的检测性能.首先,设计了可分离残差金字塔聚合模块(SRPAM),用于优化模型多尺度特征提取能力、扩大感受野,缓解CSCs检测的多尺度问题;其次,设计了一种基于平衡特征金字塔的路径聚合网络(PA-BFPN),用于提升跨层特征融合效率和小目标检测性能.最后,通过对比试验、可视化实验和消融实验证明了所提方法的有效性和优越性.其中,所提的MFPFCOS在CSCs数据集上的检测精度(mAP)能够在达到48.6%的同时,实现30的FLOPs(Floating point operations per second),表明所提方法能够在检测精度和检测速度之间保持良好的平衡. 展开更多
关键词 深度学习 目标检测 接触网支撑组件(CSCs) 路径聚合特征金字塔(PA-FPN) 空洞空间卷积池化金字塔(ASPP)
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融合先验信息的民航发动机自适应气路故障诊断方法
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作者 郭庆 刘晓阳 +2 位作者 樊俊峰 付宇 左洪福 《航空学报》 北大核心 2025年第4期150-161,共12页
针对民用航空发动机传感器数量不足、难以实现有效故障诊断的问题,提出了融合先验信息的自适应气路分析模型(AGPAM-PI),提升了发动机故障诊断的准确性与效率。AGPAM-PI结合发动机指印图的先验信息和非线性气路故障诊断方法,首先通过指... 针对民用航空发动机传感器数量不足、难以实现有效故障诊断的问题,提出了融合先验信息的自适应气路分析模型(AGPAM-PI),提升了发动机故障诊断的准确性与效率。AGPAM-PI结合发动机指印图的先验信息和非线性气路故障诊断方法,首先通过指印图对故障信息进行有效补充,对故障因子求解范围约束限定,然后再利用非线性气路分析模型进行故障诊断。以一台在实际运营过程中发生故障的CFM56-7B发动机数据进行验证,结果表明模型对该发动机的故障进行了准确的定位并通过发动机故障诊断规则分析了发动机故障模式,证明了模型的有效性。相比传统的气路故障诊断方法,先验故障信息的引入增强了单元体故障的识别能力,提高了诊断精度。 展开更多
关键词 民航发动机 故障诊断 部件级建模 信息融合 非线性气路分析
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应用偏相干方法的车内路噪噪声源识别
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作者 刘志恩 胡宇航 +3 位作者 卢炽华 程灿 李晓龙 陈弯 《噪声与振动控制》 北大核心 2025年第4期203-209,共7页
为准确、高效地识别车辆在行驶时对于结构路噪贡献量较大的传递路径,引入偏相干分析方法。该方法无须测试路径的传递函数,只需给定工况下的响应结果即可,可大大提高测试效率。针对某款汽车在40 km/h工况低频路噪凸显的问题,分别采用部... 为准确、高效地识别车辆在行驶时对于结构路噪贡献量较大的传递路径,引入偏相干分析方法。该方法无须测试路径的传递函数,只需给定工况下的响应结果即可,可大大提高测试效率。针对某款汽车在40 km/h工况低频路噪凸显的问题,分别采用部件传递路径分析法和偏相干分析法进行结构路噪传递路径贡献量分析,以部件传递路径分析法分析结果为基准验证偏相干分析法的可靠性,最终两种方法得到的结果吻合良好。基于分析结果确定车内结构路噪传递的主要路径并进行改进,通过对左右后悬架衬套结构进行优化设计,使204 Hz频率点处噪声峰值显著降低,车内驾驶员右耳处的噪声总声压级降低3.09 dB(A)。 展开更多
关键词 声学 结构路噪 部件传递路径分析法 偏相干分析法 衬套优化
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“十五五”时期现代化产业体系的发展趋势与建设路径
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作者 余东华 李墨源 《财贸研究》 北大核心 2025年第12期1-14,共14页
党的二十届四中全会指出,现代化产业体系是中国式现代化的物质技术基础,要坚持智能化、绿色化、融合化方向,构建以先进制造业为骨干的现代化产业体系。现代化产业体系是科技创新驱动、数字技术赋能、三次产业相互融合、绿色低碳发展且... 党的二十届四中全会指出,现代化产业体系是中国式现代化的物质技术基础,要坚持智能化、绿色化、融合化方向,构建以先进制造业为骨干的现代化产业体系。现代化产业体系是科技创新驱动、数字技术赋能、三次产业相互融合、绿色低碳发展且具有强大国际竞争力的新型产业体系。高质量发展新阶段,我国现代化产业体系具有完整性、先进性、安全性等时代特征和创新、协调、绿色、开放、共享等中国特色。在新一轮科技产业革命时期,现代化产业体系表现出智能化、绿色化、融合化、生态化、国际化等发展趋势,加快产业基础再造、打造国家创新体系、夯实实体经济根基、深化体制机制改革、推动产业融合发展、激发市场主体活力等是建设现代化产业体系现实路径。 展开更多
关键词 现代化产业体系 构成要素 发展趋势 时代特征 建设路径
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人力资源管理从业者数字素养的构成要素及培养路径
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作者 谢宝国 龚涵静 徐嘉 《武汉理工大学学报(信息与管理工程版)》 2025年第1期87-93,共7页
数字技术正在对人力资源管理模式和人力资源管理者产生着广泛影响。通过文献分析方法,以数字人才粮仓模型为理论依据,揭示人力资源管理从业者数字素养的内涵及构成要素,并提出了相应的培养路径。不仅为人力资源管理人才的数字素养提供... 数字技术正在对人力资源管理模式和人力资源管理者产生着广泛影响。通过文献分析方法,以数字人才粮仓模型为理论依据,揭示人力资源管理从业者数字素养的内涵及构成要素,并提出了相应的培养路径。不仅为人力资源管理人才的数字素养提供了理论基础,还提供了具有层次性和针对性的策略选择,旨在全面提升人力资源在数字时代下的数字素养水平,以更好地适应数智时代的需求。 展开更多
关键词 数字素养 人力资源管理 数字粮仓模型 构成要素 培养路径
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三峡水库消落带出露期土壤分离能力年内时空变化及其影响因素研究
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作者 肖海 朱鸿宇 +5 位作者 张伦 刘德玉 向瑞 洪焕 杨悦舒 夏振尧 《三峡大学学报(自然科学版)》 北大核心 2025年第4期16-22,共7页
为探索三峡水库消落带出露期土壤分离能力的年内时空变化特征,本文在三峡水库消落带2019年出露期内的不同时间采集不同出露高程土壤样品,测定土壤理化性质、植物生物量信息及土壤分离能力(Dc),利用Pearson相关分析、主成分回归分析(PCR)... 为探索三峡水库消落带出露期土壤分离能力的年内时空变化特征,本文在三峡水库消落带2019年出露期内的不同时间采集不同出露高程土壤样品,测定土壤理化性质、植物生物量信息及土壤分离能力(Dc),利用Pearson相关分析、主成分回归分析(PCR)、SEM结构方程模型以及PLS-PM偏最小二乘路径分析,明确土壤理化性质和植物生物量对土壤分离能力的影响及其影响路径.结果表明:Dc随时间的增加总体呈现下降趋势,随高程的增大呈现出先降后升的趋势,在高程为165~170m时达到最小;Dc与水稳性团聚体平均质量直径(MWD)、有机质含量、地上生物量和地下生物量呈现显著的负相关关系,与黏粒含量呈现显著正相关关系,PCR分析表明对Dc负向贡献度依次为MWD>有机质含量>地上生物量>地下生物量;地上生物量和地下生物量作为外生变量,通过调节次级因子(黏粒含量和有机质含量),对关键因子MWD施加间接影响,进一步作用于Dc,MWD在路径中起到核心的中介作用,是Dc的核心影响因子.本文可为三峡水库消落带的水土保持和生态修复提供理论依据,对三峡水库的防灾减灾具有一定的指导意义. 展开更多
关键词 土壤分离能力 三峡水库消落带 时空变化 结构方程模型 偏最小二乘路径分析 主成分回归分析
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