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CNN-based multi-output regression model to estimate infrastructural surface crack dimensions adopting a generalised patch size and FWHM-based width quantification
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作者 Sudipta Debroy Arjun Sil 《Digital Twins and Applications》 2025年第1期75-102,共28页
To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks o... To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks obtained from a public dataset are cropped into patches of 256 square pixels that are classified with a pre-trained deep convolution neural network,the true positives are segmented,and crack properties are extracted using two different methods.The first method is primarily based on active contour models and level-set segmentation and the second method consists of the domain adaptation of a mathematical morphology-based method known as FIL-FINDER.A statistical test has been performed for the comparison of the stated methods and a database prepared with the more suitable method.An advanced convolution neural network-based multi-output regression model has been proposed which was trained with the prepared database and validated with the held-out dataset for the prediction of crack-length,crack-width,and width-uncertainty directly from input image patches.The pro-posed model has been tested on crack patches collected from different locations.Huber loss has been used to ensure the robustness of the proposed model selected from a set of 288 different variations of it.Additionally,an ablation study has been conducted on the top 3 models that demonstrated the influence of each network component on the pre-diction results.Finally,the best performing model HHc-X among the top 3 has been proposed that predicted crack properties which are in close agreement to the ground truths in the test data. 展开更多
关键词 ablation CNN convolution neural network CRACK crack patch estimation FWHM length multi-output regression segmentation uncertainty width
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Accurate Interconnection Length and Routing Channel Width Estimates for FPGAs
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作者 高海霞 马晓华 杨银堂 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第7期1196-1200,共5页
We study the problem of the prediction of interconnection dimensions for FPGAs, including estimating interconnection length and channel width. Experimental results show that our estimates are more accurate than those ... We study the problem of the prediction of interconnection dimensions for FPGAs, including estimating interconnection length and channel width. Experimental results show that our estimates are more accurate than those of existing methods. 展开更多
关键词 FPGA interconnection length estimation channel width estimation
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Sensitivity analysis of the vane length and passage width for a radial type swirler employed in a triple swirler configuration 被引量:4
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作者 Foad Vashahi Shahnaz Rezaei +1 位作者 Reza Alidoost Dafsari Jeekeun Lee 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期363-375,共13页
The design of axial or radial swirlers typically governs a number of geometrical parameters that are determined by the desired flow field.In the meantime,the number of unknown parameters increases with the number of c... The design of axial or radial swirlers typically governs a number of geometrical parameters that are determined by the desired flow field.In the meantime,the number of unknown parameters increases with the number of concentrically mounted swirlers.The available literature is nonetheless limited,and designers are obligated to increase the number of initial assumptions.In this article,three kinds of triple swirlers are employed and simulations are performed to determine the effect of each parameter on the swirler performance.Based on the correlation provided,overlengthening the radial vane length could result in significant changes in the flow field from the jetlike pattern to a wide swirl-jet angle due to the Coanda effect.Passage width should also have the potential to alter the swirl-jet angle and velocity field at the exit of the swirler. 展开更多
关键词 TRIPLE SWIRLER SWIRLER design RADIAL VANE length PASSAGE width Reynolds averaged Navier–Stokes
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Seed Length Controlled by Same Locus in Four Different AA Genome Species of Genus Oryza 被引量:1
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作者 ZHANG Yu LI Jing +6 位作者 ZHOU Jia-wu XU Peng DENG Xian-neng YANG Fei DENG Wei HU Feng-yi TAO Da-yun 《Rice science》 SCIE 2014年第1期20-28,共9页
To broaden the genetic basis and overcome the yield plateau in Asian cultivated rice, the exploitation and utilization of favorable alleles from rice species with the AA genome has become important and urgent in moder... To broaden the genetic basis and overcome the yield plateau in Asian cultivated rice, the exploitation and utilization of favorable alleles from rice species with the AA genome has become important and urgent in modern breeding programs. Four different interspecific populations were used to detect quantitative trait locus (QTL) for seed length, including a BC4F2 population derived from Oryza glumaepatula crossed with Dianjingyou 1 (a japonica cultivar), a BC4F2 population derived from O. nivara crossed with Dianjingyou 1, a BCzF1 population derived from a cross between O. Iongistaminata and RD23 (an indica cultivar), and a BCsF1 population derived from a cross between O. glaberrima and Dianjingyou 1. The QTLs for seed length in four different populations were termed as SL-3a, SL-3b, SL-3c and SL-3d, respectively. They had good collinearity and accounted for 49% to 60% of the phenotypic variations. Sequencing data indicated that four QTLs were different alleles of GS3 which were responsible for the seed length variation between O. sativa and its four AA genome relatives. These results will be valuable for confirming the evolution of GS3 and also be helpful for rice breeding. 展开更多
关键词 seed length O. glumaepatula O. nivara O. Iongistaminata O. glaberrima quantitative trait locus
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Impact of Channel Length and Width for Charge Transportation of Graphene Field Effect Transistor
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作者 Kamal Hosen Md.Rasidul Islam Kong Liu 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第6期757-763,I0003,共8页
The effect of channel length and width on the large and small-signal parameters of the graphene field effect transistor have been explored using an analytical approach.In the case of faster saturation as well as extre... The effect of channel length and width on the large and small-signal parameters of the graphene field effect transistor have been explored using an analytical approach.In the case of faster saturation as well as extremely high transit frequency,the graphene field effect transistor shows outstanding performance.From the transfer curve,it is observed that there is a positive shift of Dirac point from the voltage of 0.15 V to 0.35 V because of reducing channel length from 440 nm to 20 nm and this curve depicts that graphene shows ambipolar behavior.Besides,it is found that because of widening channel the drain current increases and the maximum current is found approximately 2.4 mA and 6 mA for channel width 2μm and 5μm respectively.Furthermore,an approximate symmetrical capacitance-voltage(C-V)characteristic of the graphene field effect transistor is obtained and the capacitance reduces when the channel length decreases but the capacitance can be increased by raising the channel width.In addition,a high transconductance,that demands high-speed radio frequency(RF)applications,of 6.4 mS at channel length 20 nm and 4.45 mS at channel width 5μm along with a high transit frequency of 3.95 THz have been found that demands high-speed radio frequency applications. 展开更多
关键词 GRAPHENE Graphene field effect transistor Large signal Small-signal Channel length Channel width
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Genetic Analysis of Leaf Length and Leaf Width in Bitter Gourd
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作者 Ziji LIU Yu NIU +1 位作者 Yan YANG Baibi ZHU 《Medicinal Plant》 CAS 2022年第6期78-80,共3页
[Objectives]To explore the genetic mechanism that leaf length and leaf width in bitter gourd has realistic guiding significance for formulating breeding strategy.[Methods]In this paper,the cross was made between CN19-... [Objectives]To explore the genetic mechanism that leaf length and leaf width in bitter gourd has realistic guiding significance for formulating breeding strategy.[Methods]In this paper,the cross was made between CN19-1 and Thai4-6 and an F2segregation population was constructed.The genetic characteristics of leaf length and leaf width were analyzed by employing the major gene plus polygene mixed genetic model.[Results]The data analysis results demonstrated that the leaf length and leaf width of the F_(2) segregation population showed continuous distribution.The optimum model for leaf length genetic analysis was A-1,the additive effect value of the major gene was 3.1766,the dominant effect value was-3.1766,and the heritability was 74.51%.The optimum model for leaf width genetic analysis was B-1.The additive effect values of 2 pairs of major genes controlling the leaf width were 3.1917 and 0.9623,respectively.The dominant effect values were-1.3135 and-0.3463,respectively.The additive×additive interaction effect was-0.3591,the additive×dominant interaction effect was-0.2570,the dominant×additive interaction effect was 1.9916,the dominant×dominant interaction effect was 1.9686.The heritability of major genes was 96.67%.[Conclusions]This study is expected to provide a theoretical basis for the breeding of bitter gourd. 展开更多
关键词 Bitter gourd Genetic model Leaf length Leaf width Genetic analysis
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Effect of Overlap Stress as Well as Tie Beam Length and Width on Settlement of Isolated Footings Using Finite Element
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作者 Mahmoud Abo Bakr El Sideek 《Open Journal of Civil Engineering》 2014年第1期35-44,共10页
Effects of tie beam length, width and overlap stress on settlement of foundations have been investigated. In this investigation square concrete footings have been used with dimensions (B × B × d) where (d) i... Effects of tie beam length, width and overlap stress on settlement of foundations have been investigated. In this investigation square concrete footings have been used with dimensions (B × B × d) where (d) is footing depth and (B) is footing width (1, 1.5,2 m). Width of tie beam (b) has been taken equal to 0.25, 0.30, 0.40, 0.50 and 0.75 (m). Tie beam length (L) has been taken varying from B till 3B with same footing depth = 0.50 m. Effect of overlap stress on settlement as well as effect of tie beam width and length on settlement has been determined. Also, the efficiency of tie beam length and width has been obtained. An equation is presented to compute the overlap stress zone in case of existing tie beam. It is found that the settlement increases with increasing the length of tie beam which is clear after the effect of the overlap stresses zone. The width of overlap stress zone case of existing tie beam has been found to be equal to (1.6 -1.75) B. The settlement of footings decreases with increasing tie beam width. It is found that the settlement after the effect of the overlap stress zone increases with increasing the length of tie beam. 展开更多
关键词 Effect OVERLAP Stress Tie Beam length and width SETTLEMENT ISOLATED FOOTINGS Finite Element
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The Paradigm of Surgical Ellipse Dimensions: Are the Length-to-Width Ratio of 3 to 4 and a Vertex Angle of 30&ordm;Correct?
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作者 Tamara R. Tilleman M. M. Tilleman M. H. A. Neumann 《Surgical Science》 2013年第4期236-240,共5页
Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. T... Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. These dimensions became axiomatic in cutaneous surgery and have been taught in the apprenticeship model for years. The present article examines the validity of that paradigm. Methods: We collected data from two sources: ellipses described in the literature (57 cases);and elliptical excisions performed at the authors’ outpatient clinic (83 cases). The surgical ellipse lengths, widths, and vertex angles were analyzed, and the data were compared to a mathematical formula used to generate a fusiform ellipse. Results: The length-to-width ratio of 3 - 4 was found to be inconsistent with the recommended vertex angle of 30o. In fact, a length-to-width ratio of 3 - 4 determines a vertex angle of 48o - 63o. A 30o vertex angle is only feasible with long length-to-width ration of about 7.5. Conclusions: The paradigm that surgical ellipses should have a vertex angle of 30o with length-to-width ratio of 3 - 4 is incorrect. Evidence from actual surgical practice and from mathematical formulation shows that either the length-to-width ratio must be larger than 3 - 4 or the vertex angle must be larger than 30 degrees. 展开更多
关键词 Elliptical Excision length-to-width RATIO of 3 - 4 30o Vertex Angle
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OsDA1 positively regulates grain width in rice
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作者 Cong Li Jun Liu +4 位作者 Liya Zhang Tao Li Hongyu Li Bin Liu Tao Zhao 《The Crop Journal》 SCIE CSCD 2024年第1期92-101,共10页
The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed i... The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed in young spikelets and glumes.Its overexpression led to enlarged seeds with increased width and decreased length/width ratio(LWR)and knocking out OsDA1 reduced grain width and increased grain length and LWR.A R310K point mutation in the DA1-like domain is a potential target for breeding for increased grain width and length.OsDA1 interacted with TCP gene-family proteins to regulate grain size and shape.Our findings deepen our understanding of the molecular mechanisms underlying grain size regulation and provide useful information for improving grain yield. 展开更多
关键词 RICE Osda1 Grain size Grain shape Grain length/width ratio TCP
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Red blood cell distribution width levels predict prolonged hospital stay for infants after cardiopulmonary bypass surgery
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作者 廖秋凤 刘琦 +1 位作者 李思敏 钟杏 《South China Journal of Cardiology》 CAS 2024年第2期89-98,共10页
Background Thered cell distribution width(RDW)is a parameter that reflects the heterogeneity of red blood cell volume and size,and it is commonly used in the diagnosis of anemia in patients.RDW may serve as a predicto... Background Thered cell distribution width(RDW)is a parameter that reflects the heterogeneity of red blood cell volume and size,and it is commonly used in the diagnosis of anemia in patients.RDW may serve as a predictor of the postoperative prognosis of surgical patients in the intensive care unit.This study evaluated the predictive capability of RDW for outcomes in infants after cardiopulmonary bypass surgery.Methods A retrospective cohort study was conducted at Guangdong Provincial People's Hospital enrolling infants(≤1 year)who underwent cardiac surgery between January 2019 and April 2019.The infants were divided into two groups based on their preoperative RDW levels(<14.5% and≥14.5%).The primary outcome measured was the prolonged hospital stay post-operation.The association between RDW levels and prolonged hospital length of stay was evaluated using multivariate Logistic regression,presenting the adjusted odds ratio with a 95%confidence interval(CI).Additionally,interaction and subgroup analyses were performed to assess the consistency of these correlations.Results A total of 186 infants were included in the study.After adjusting for potential confounders,multivariate logistic regression models demonstrated a significant association between RDW and prolonged length of stay(LOS)in hospital when treated as a continuous variable(change per 1SD,OR:1.50,95%CI:1.06-2.11,P=0.021).Categorizing RDW as a variable revealed that higher RDW levels(≥14.5%)were significantly associated with an increased risk of prolonged LOS compared to lower levels(<14.5%)(OR:9.72,95%CI:2.87-32.91,P<0.001).Receiver operating curves(ROC)analysis showed that RDW levels exhibited relatively higher diagnostic value for predicting prolonged LOS(AUC=0.697,95%CI:0.617-0.776,P<0.05).Stratified analyses further showed that depending on the variable testing,an association between higher RDW levels and prolonged hospital length of stay in different subgroups was observed.Conclusions Elevated RDW levels in infants undergoing cardiac surgery involving cardiopulmonary bypass may signify prolonged recovery periods. 展开更多
关键词 INFANTS Cardiac surgery Red cell distribution width Prolonged length of stay in hospital
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不同结构参数下的半U形地下空间烟气运动参数的机器学习预测 被引量:1
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作者 徐志胜 殷耀龙 +2 位作者 雷志强 陈诗仪 应后淋 《灾害学》 北大核心 2025年第1期67-73,共7页
结合火灾数值模拟(FDS)与机器学习方法,该文对半U形地下空间火灾时的烟气运动进行了深入分析。研究发现,在预测烟气回流长度及烟气最高温升方面,BP神经网络相比于支持向量机回归(SVR)展现了更高的精度,其决定系数超过了95%,而相对误差... 结合火灾数值模拟(FDS)与机器学习方法,该文对半U形地下空间火灾时的烟气运动进行了深入分析。研究发现,在预测烟气回流长度及烟气最高温升方面,BP神经网络相比于支持向量机回归(SVR)展现了更高的精度,其决定系数超过了95%,而相对误差仅集中在20%以内,显著优于SVR方法。通过shap值解释机器学习模型,并结合FDS数值模拟的结果,揭示坡高是影响烟气回流长度的决定性因素,且坡高的增大、宽度的减小或热释放速率增大均会缩短烟气回流。同时,热释放速率是影响烟气最高温升的主要因素,受坡高影响较大,而宽度的减小虽能在一定幅度上降低最高烟气温升,但效果并不显著。该研究拓展了地下空间火灾烟气运动参数的预测方法,为地下空间火灾动力学行为预测及通风排烟系统的优化设计贡献了创新性的方法。 展开更多
关键词 半U形地下空间 机器学习 截面宽度 坡高 烟气回流长度 最高烟气温升
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基于种子生长策略与深度神经网络的电力工作票智能识别方法
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作者 廖美英 周俊煌 张勇军 《浙江电力》 2025年第6期91-99,共9页
针对电力工作票的数字化需求,提出了一种基于种子生长策略与DenseNet(稠密连接网络)的智能识别方法。首先,在文本检测阶段,利用种子生长策略,通过选取初始种子点并逐步扩展候选区域,有效提升了对不规则文本区域的定位精度。然后,在文字... 针对电力工作票的数字化需求,提出了一种基于种子生长策略与DenseNet(稠密连接网络)的智能识别方法。首先,在文本检测阶段,利用种子生长策略,通过选取初始种子点并逐步扩展候选区域,有效提升了对不规则文本区域的定位精度。然后,在文字识别阶段,结合DenseNet的深层特征提取能力与CTC技术的不定长序列对齐机制,提升了字符序列的识别效果。最后,通过实验证明所提方法在设备代码、电气符号等行业专用字符的识别中表现出更高的准确率,显著降低了误识别率,有效满足了电力工作票数字化处理的需求,具有较强的实用价值和应用前景。 展开更多
关键词 种子生长策略 深度神经网络 不定长文本识别 电力工作票
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饱和红黏土中水平矩形锚板上拔承载特性试验研究 被引量:2
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作者 罗广 胡伟 +2 位作者 杜弘毅 王辉 张翰林 《科学技术与工程》 北大核心 2025年第7期2897-2903,共7页
针对红黏土地基中水平矩形锚板上拔承载特性,通过自制的可视化拉拔模型试验系统,结合数字照相测量技术,开展了饱和红黏土地基中水平矩形锚板的竖向拉拔模型试验。结果表明:锚周土体滑动面随埋深比的变化呈现不同形态,但初始角并不随埋... 针对红黏土地基中水平矩形锚板上拔承载特性,通过自制的可视化拉拔模型试验系统,结合数字照相测量技术,开展了饱和红黏土地基中水平矩形锚板的竖向拉拔模型试验。结果表明:锚周土体滑动面随埋深比的变化呈现不同形态,但初始角并不随埋深比发生变化。荷载位移曲线一般具有较明显的峰值特征,但随着埋深比的增大,该特征逐渐减弱;埋深比相同时,长宽比越小,锚板承载的三维特性越显著,曲线的峰值特征也越明显。承载力系数随着埋深比的增加呈增大趋势,但不同长宽比下的规律有所差别;承载力系数随长宽比的增加呈减小趋势,且不同埋深比下的变化规律较为一致。结论:对于试验红黏土,至少在埋深比4的范围内,锚板可归为浅埋型,埋深比大于8的情况则已属于深埋型。同等条件下,受黏聚力和剪胀性的影响,锚板抗拔承载力系数在红黏土地基中的数值介于松砂地基和密砂地基之间。 展开更多
关键词 矩形锚板 红黏土 长宽比 埋深比 滑动面 极限承载力
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杨树6个“无絮”无性系木材主要解剖特征变异规律分析 被引量:1
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作者 刘扬光 刘俊龙 +5 位作者 苗婷婷 丁昌俊 秦生磊 石鑫 余敏 刘盛全 《林业工程学报》 北大核心 2025年第2期42-50,共9页
以6个“无絮”雄性良种无性系杨树为研究对象,对其木材解剖特性纵向和径向变异规律进行分析,从而为筛选优良杨树无性系提供理论依据。通过采集安徽省太和县林场7年生鲁林9号杨、江淮1号杨、巨霸杨、美洲黑杨2025号、中嘉2号杨和xl-90号... 以6个“无絮”雄性良种无性系杨树为研究对象,对其木材解剖特性纵向和径向变异规律进行分析,从而为筛选优良杨树无性系提供理论依据。通过采集安徽省太和县林场7年生鲁林9号杨、江淮1号杨、巨霸杨、美洲黑杨2025号、中嘉2号杨和xl-90号杨6个无性系杨树木材,分析不同无性系杨树的纤维长度、纤维宽度、纤维长宽比和双壁厚的变异规律。结果表明:6个无性系杨树的纤维长度、纤维宽度、纤维长宽比和双壁厚均值分别为863.01~939.94、21.00~22.28、41.86~46.01和5.80~8.18μm,6个杨树无性系纤维长度为863.01~939.94μm,属于中级长度。江淮1号杨的纤维长度和纤维长宽比在0.05水平上显著高于其他无性系,xl-90杨的纤维宽度在0.05水平上显著高于其他无性系,美洲黑杨2025号的双壁厚在0.05水平上显著高于其他无性系杨树;各无性系杨树木材解剖特征在树干纵向上的变化规律差异较大,并且同一无性系的解剖特征纵向不同高度上的差异显著;径向上由髓心向外,各无性系杨树的纤维长度、纤维宽度和纤维长宽比随着年轮的增加而显著增加。综合分析各解剖特征指标,江淮1号杨同其他无性系相比,其木材最适合用于纸浆造纸的原材料。 展开更多
关键词 杨木 纤维长宽度 长宽比 双壁厚 变异规律
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甘蓝型油菜角果长度和每角粒数基因定位以及角果皮转录组动态分析 被引量:1
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作者 王晓琳 刘忠松 +1 位作者 康雷 杨柳 《作物学报》 北大核心 2025年第4期888-899,共12页
甘蓝型油菜(Brassica napus L.)是全球重要的油料作物,提高其产量是育种的重要目标。单位面积角果数、每角粒数和粒重是油菜产量的3个构成因子。角果长度虽然不是油菜产量的直接构成因素,但影响每角粒数和粒重,进而影响油菜产量。本研... 甘蓝型油菜(Brassica napus L.)是全球重要的油料作物,提高其产量是育种的重要目标。单位面积角果数、每角粒数和粒重是油菜产量的3个构成因子。角果长度虽然不是油菜产量的直接构成因素,但影响每角粒数和粒重,进而影响油菜产量。本研究以角果长度和每角粒数差异显著的亲本YA和中双11号(ZS11)及用其构建的包含211个株系的重组自交系(RIL)群体为材料,在长沙秋播和民乐夏播,考察角果长度和每角粒数,通过群体及双亲重测序对上述2个性状进行QTL定位,结果在2个环境下均检测到1个角果长度和每角粒数的主效QTL,其位于A09染色体。双亲开花后3~21d,角果皮转录组测序分析发现角果皮光合作用、激素和次生代谢物合成的基因在角果发育中发挥了重要作用,功能注释认为BnaA09.CYP78A9、BnaC08.SCL13和BnaA04.ARL等参与生长素响应和传导的基因为调控油菜角果长度的候选基因。这些结果为进一步开展油菜角果长度基因精细定位及其调控机制研究奠定了基础。 展开更多
关键词 甘蓝型油菜 角果长度 每角粒数 数量性状位点 转录组分析
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小麦小旗叶突变性状基因定位与遗传分析
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作者 杨思杰 杜启迪 +6 位作者 柴守玺 熊宏春 谢永盾 赵林姝 古佳玉 郭会君 刘录祥 《作物学报》 北大核心 2025年第6期1548-1557,共10页
叶片形态作为株型结构的核心特征,对光合作用效率、作物产量及胁迫响应等具有重要影响。旗叶是小麦进行光合作用的重要功能器官,其光合效率直接影响小麦产量,深入挖掘旗叶发育调控基因有助于培育高产小麦品种。本研究以小麦品种京411为... 叶片形态作为株型结构的核心特征,对光合作用效率、作物产量及胁迫响应等具有重要影响。旗叶是小麦进行光合作用的重要功能器官,其光合效率直接影响小麦产量,深入挖掘旗叶发育调控基因有助于培育高产小麦品种。本研究以小麦品种京411为野生型,经诱变获得了表型稳定的小旗叶突变体je0261。该突变体表现旗叶变窄变短,旗叶叶长减小38.9%,叶宽减少29.3%,叶面积减小56.7%。根据突变体与野生型的F2和F3代表型数据分析表明,旗叶宽窄和长短性状分别受1对主效隐性基因控制。采用混合群体分离分析法(BSA),结合测序所得SNP位点,在7A染色体上开发了7个KASP标记,将控制叶长、叶宽的目标基因同时定位在7A染色体长臂1.18 cM遗传区段内,对应中国春参考基因组8.08 Mb的物理区间。2个基因之间的遗传距离为1.00 cM,推断是2个新的控制旗叶宽度和长度的主效基因。本研究所鉴定的小麦旗叶大小和宽窄调控区段有助于深入解析小麦旗叶叶面积形成的遗传基础,为进一步改良小麦叶型提供新基因源。 展开更多
关键词 小麦 旗叶叶长 旗叶叶宽 遗传分析 基因定位
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AlGaN/GaN HEMT器件有效栅长和栅宽提取
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作者 吴淇暄 张贺秋 +4 位作者 朱江 宁思源 代晓 王子坤 梁红伟 《大连理工大学学报》 CAS 北大核心 2025年第1期105-110,共6页
有效栅长、有效栅宽和沟道电阻等AlGaN/GaN高电子迁移率晶体管(HEMT)参数对于工艺控制和器件设计非常重要.基于AlGaN/GaN HEMT器件源漏之间的总电阻与栅长及栅宽的倒数之间的线性关系,提出了一种简单方法提取有效栅长和有效栅宽.制作了... 有效栅长、有效栅宽和沟道电阻等AlGaN/GaN高电子迁移率晶体管(HEMT)参数对于工艺控制和器件设计非常重要.基于AlGaN/GaN HEMT器件源漏之间的总电阻与栅长及栅宽的倒数之间的线性关系,提出了一种简单方法提取有效栅长和有效栅宽.制作了两组AlGaN/GaN HEMT器件,这两组器件的源漏间距为80μm,栅源间距为10μm.其中一组器件固定栅宽为400μm,栅长分别为10、20、30、40、50、60μm;另一组器件固定栅长为40μm,栅宽分别为200、300、400、500、600、800μm.通过研究源漏之间的总电阻随栅长和栅宽变化规律,获得栅长与有效栅长的差值为0.48989μm,栅宽与有效栅宽的差值为-11.12191μm. 展开更多
关键词 ALGAN/GAN高电子迁移率晶体管 器件参数 有效栅长 有效栅宽
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杀菌剂1号处理存放不同时间对西瓜甜瓜种子萌发的影响
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作者 王梦茜 袁琴 +7 位作者 潘磊 袁胜楠 魏浩宇 关巍 杨玉文 马云龙 王燕 赵廷昌 《中国瓜菜》 北大核心 2025年第9期92-97,共6页
瓜类细菌性果斑病是一种危害西甜瓜生产的种传病害,防治的首要措施是种子消毒。为检测杀菌剂1号处理后存放不同时间对西甜瓜种子发芽的影响,本研究使用皿测法测定了杀菌剂1号处理西瓜种子IVF-01、甜瓜种子IVF88、IVF-NLL后,室温下存放... 瓜类细菌性果斑病是一种危害西甜瓜生产的种传病害,防治的首要措施是种子消毒。为检测杀菌剂1号处理后存放不同时间对西甜瓜种子发芽的影响,本研究使用皿测法测定了杀菌剂1号处理西瓜种子IVF-01、甜瓜种子IVF88、IVF-NLL后,室温下存放不同时间后种子的萌发率及芽长。结果表明,除存放1 d的IVF-01萌发率显著低于清水处理(CK)外,其他处理对种子萌发无显著影响,存放7、90 d萌发率分别提高了0.81%和0.41%;处理IVF88和IVF-NLL后存放90 d,萌发率分别提高了7.67%和1.44%,其他处理均对IVF88和IVF-NLL萌发无显著影响。除存放1、7、90 d的IVF-01芽长低于CK外,其他处理对种子的芽长无显著影响,处理后存放15、30 d的芽长增加了1.38%和6.35%;除存放1 d抑制了IVF-NLL芽生长,其他处理对IVF-NLL和IVF88芽长无显著影响,存放30、180 d时,IVF-NLL芽长分别增加了3.62%和4.89%。综上所述,杀菌剂1号处理后存放不同时间,对供试3类种子萌发率和芽长的影响不明显,甚至能促进萌发和生长。本研究结果为合理使用杀菌剂1号防治瓜类细菌性果斑病提供了理论基础和科学依据。 展开更多
关键词 杀菌剂1号 西瓜甜瓜种子 萌发率 芽长
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甘蓝型油菜粒重和角果长遗传机理的研究进展
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作者 李盼盼 林俐 吴健 《分子植物育种》 北大核心 2025年第22期7488-7495,共8页
甘蓝型油菜在世界范围内有广泛的种植,是世界上三大油料作物之一,它不仅是中国食用植物油的主要来源,而且还可以作为动物优质的蛋白饲料以及生物能源的原材料等。但随着人口的快速增长,中国食用油的自给率严重不足,因此提高油菜产量是... 甘蓝型油菜在世界范围内有广泛的种植,是世界上三大油料作物之一,它不仅是中国食用植物油的主要来源,而且还可以作为动物优质的蛋白饲料以及生物能源的原材料等。但随着人口的快速增长,中国食用油的自给率严重不足,因此提高油菜产量是缓解中国食用油短缺、减少中国食用油对国外依存度的重要举措。粒重与角果长是油菜重要的产量相关性状,目前我们对这2个性状的遗传调控还知之甚少,因此解析油菜粒重和角果长的遗传机理,将有助于指导油菜高产育种。本研究对近些年国内外在油菜粒重和角果长遗传机理上的研究进展进行了综述,将以往的研究进行了归纳总结发现:虽然以往研究在不同的连锁群上鉴定出大量调控粒重和角果长相关的QTLs,但只有少数QTLs(BnaA.ARF18,BnaA9.CYP79A9及BnaC7.ROT3)被成功克隆,这些研究将为油菜的遗传改良提供理论支撑。同时本研究也对目前克隆QTL存在的困难进行了阐述和展望,以期为粒重和角果长的遗传改良提供参考。 展开更多
关键词 甘蓝型油菜 粒重 角果长 QTL
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沟道宽度及长度对DSOI晶体管电离总剂量效应的影响
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作者 杨弘毅 郑齐文 +2 位作者 崔江维 李豫东 郭旗 《现代应用物理》 2025年第2期178-186,共9页
双埋氧层绝缘体上硅(double silicon-on-insulator,DSOI)技术凭借双埋氧层的介质隔离优势以及背栅电极的动态调控电场能力,成为新一代抗辐射器件的重点发展方向。本文针对H栅结构DSOI器件在电离辐照下的总剂量效应,研究了沟道宽度及长... 双埋氧层绝缘体上硅(double silicon-on-insulator,DSOI)技术凭借双埋氧层的介质隔离优势以及背栅电极的动态调控电场能力,成为新一代抗辐射器件的重点发展方向。本文针对H栅结构DSOI器件在电离辐照下的总剂量效应,研究了沟道宽度及长度对其电学性能的差异性影响。随着沟道宽度的增加,阈值电压漂移显著增大,而增加沟道长度则能够有效降低这种漂移。此外,不同沟道宽度及长度的器件在辐照后的关态漏电流表现出显著差异,短沟道器件的漏电流增加更明显,表现出更高的辐射敏感性。TCAD仿真结果表明:沟道宽度与长度均通过改变埋氧层中电场的方式影响辐射诱导氧化物陷阱电荷的产生,在更宽、更短的器件中观察到最大的场强。氧化物陷阱电荷的积聚会改变背界面表面的静电势,进而影响界面陷阱电荷产生。两者的空间密度分布差异是器件辐射敏感性呈现沟道尺寸依赖性的主因。 展开更多
关键词 电离总剂量效应 DSOI NMOSFET 沟道长度 沟道宽度 陷阱电荷
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