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随机存储下Leaf型仓储布局设计及其拣选路径策略研究
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作者 柳虎威 周丽 +2 位作者 赵俊辉 王繁 杨江龙 《工程数学学报》 北大核心 2025年第3期529-553,共25页
仓库布局设计是影响拣选作业行走路径和拣选效率的重要因素。在鱼骨布局和flying-V型布局的基础上,以货架摆放角度及斜向主通道角度为出发点,对Leaf型仓储布局进行研究,构建Leaf型仓储布局的有效存储面积利用率模型,探究货架摆放角度及... 仓库布局设计是影响拣选作业行走路径和拣选效率的重要因素。在鱼骨布局和flying-V型布局的基础上,以货架摆放角度及斜向主通道角度为出发点,对Leaf型仓储布局进行研究,构建Leaf型仓储布局的有效存储面积利用率模型,探究货架摆放角度及斜向主通道角度对有效存储面积的影响。进而构建Leaf型仓储布局中的S型和返回型拣选路径随机模型,并完成对其的近似计算与仿真验证。数值实验结果表明,在Leaf型仓储布局中,布局的改进对实际存储面积的影响较小,与鱼骨布局和flying-V型布局相差分别为1.6%与2.7%,可进一步对Leaf型仓储布局拣选行走路径进行研究,在特定货架摆放角度及斜向主通道角度下,返回型路径与S型路径均能取得最优值,且S型路径结果优于返回型路径。 展开更多
关键词 leaf型仓储布局 拣选路径 改进型布局 随机存储
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Studies on the anti-hair loss mechanism of Aquilaria sinensis leaf extract by integrated metabolomics and network pharmacology
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作者 Zhengang Peng Zhengwan Huang +1 位作者 Zhe Liu Xiaoxiao Lin 《日用化学工业(中英文)》 北大核心 2025年第6期767-778,共12页
The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,... The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,and the network pharmacology was used to elucidate their anti-hair loss mechanism,which was verified by molecular docking technology.572 active compounds were identified from the ASE by metabolomics methods,where there are 1447 corresponding targets and 492 targets related to hair loss,totaling 88 targets.20 core active substances were identified by constructing a network between common targets and active substances,which include vanillic acid,chorionic acid,caffeic acid and apigenin.The five key targets of TNF,TP53,IL6,PPARG,and EGFR were screened out by the PPI network analysis on 88 common targets.The GO and KEGG pathway enrichment analysis showed that the inflammation,hormone balance,cell growth,proliferation,apoptosis,and oxidative stress are involved.Molecular docking studies have confirmed the high binding affinity between core active compounds and key targets.The drug similarity assessment on these core compounds suggested that they have the potential to be used as potential hair loss treatment drugs.This study elucidates the complex molecular mechanism of ASE in treating hair loss,and provides a reference for the future applications in hair care products. 展开更多
关键词 metabolomics network pharmacology hair loss Aquilaria sinensis leaf extract molecular docking
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Research Progress on Transmission,Physiological Races,Differentiation,Resistance Breeding and Molecular Genetic Mechanism of Soybean Frogeye Leaf Spot Disease
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作者 Ning Hailong Wang Yidi +4 位作者 Guan Fangshuo HuBo Zhang Shuzhen Xu Pengfei Li Wenxia 《Journal of Northeast Agricultural University(English Edition)》 2025年第2期82-96,共15页
Soybean frogeye leaf spot(FLS)disease is a worldwide disease caused by Cercospora sojina Hara.It is one of the major diseases suffered by soybean during the growth cycle,which seriously damages the yield and seed qual... Soybean frogeye leaf spot(FLS)disease is a worldwide disease caused by Cercospora sojina Hara.It is one of the major diseases suffered by soybean during the growth cycle,which seriously damages the yield and seed quality of soybean.The current resistant varieties are difficult to meet the production demand.The breeders have identified 50 different physiological small species and discussed the physiological and biochemical characteristics of soybean resistance to FLS.In soybean disease resistance breeding,resistance resources are screened for the main physiological races in different countries,resistance materials are created,more than 100 genome regions associated with resistance are located,and 12 resistance-related genes are identified.In order to promote the research of soybean disease resistance breeding,this paper expounded and analyzed the pathogenesis characteristics of soybean FLS,the division of races,the physiological and biochemical mechanism of soybean resistance to FLS disease,quantitative trait locus(QTL),quantitative trait nucleotides(QTN),genes of resistance sites,the screening of resistant germplasm resources,and the breeding of new varieties,so as to gain an in-depth understanding of the pathogenesis principle of soybean FLS disease.In order to provide a theoretical basis and technical support for the breeding of soybean FLS disease,the resistance mechanism of soybean FLS disease was analyzed from the molecular level. 展开更多
关键词 SOYBEAN frogeye leaf spot resistance inheritance disease resistance mechanism
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Genomic Selection for Frogeye Leaf Spot Resistance in Soybean
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作者 Yao Lanning Chen Yizhi +4 位作者 Li Haochen Zhang Yue Xia Mingyu Ning Shicheng Ning Hailong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期11-19,共9页
Soybean frogeye leaf spot(FLS) disease is a global disease affecting soybean yield, especially in the soybean growing area of Heilongjiang Province. In order to realize genomic selection breeding for FLS resistance of... Soybean frogeye leaf spot(FLS) disease is a global disease affecting soybean yield, especially in the soybean growing area of Heilongjiang Province. In order to realize genomic selection breeding for FLS resistance of soybean, least absolute shrinkage and selection operator(LASSO) regression and stepwise regression were combined, and a genomic selection model was established for 40 002 SNP markers covering soybean genome and relative lesion area of soybean FLS. As a result, 68 molecular markers controlling soybean FLS were detected accurately, and the phenotypic contribution rate of these markers reached 82.45%. In this study, a model was established, which could be used directly to evaluate the resistance of soybean FLS and to select excellent offspring. This research method could also provide ideas and methods for other plants to breeding in disease resistance. 展开更多
关键词 LASSO regression stepwise regression genomic selection model SOYBEAN frogeye leaf spot(FLS)disease
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LEAFS对海洋沉积物中金钯元素的测量 被引量:2
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作者 吉望西 陈瓞延 +1 位作者 林琴如 马万云 《北京大学学报(自然科学版)》 CAS CSCD 北大核心 1997年第2期163-166,共4页
采用LEAFS对海洋沉积物中的金钯元素进行了测量。在测量过程中,对硫脲和黄原脂棉两种化学处理方法进行了比较。用黄原脂棉处理并完成了全部样品测量。对LEAFS的检出限和应用特性做了简单的评价。
关键词 leafS 海洋沉积物 测量
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Leaf-TCAM:一种并行IP路由查找方法及性能分析 被引量:2
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作者 朱国胜 余少华 戴锦友 《计算机科学》 CSCD 北大核心 2010年第4期63-66,共4页
分析了互联网路由表和路由更新的特征,提出了一种基于叶子节点进行路由表分区的并行IP路由查找方法Leaf-TCAM,分区子表按照流量特征在K个TCAM芯片中进行均衡分布。分析表明,该路由查找方法在引入0.1*(K-1)冗余的前提下具有K-1倍加速因... 分析了互联网路由表和路由更新的特征,提出了一种基于叶子节点进行路由表分区的并行IP路由查找方法Leaf-TCAM,分区子表按照流量特征在K个TCAM芯片中进行均衡分布。分析表明,该路由查找方法在引入0.1*(K-1)冗余的前提下具有K-1倍加速因子。该方法无需进行前缀扩展,90%以上的路由前缀无需排序,可以采用随机更新;同时还具有分区均匀、分区溢出代价小等特点,而功耗只有传统单片方案的12%。 展开更多
关键词 路由查找 并行 leaf-TCAM
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Varietal Difference in Leaf Nitrogen Content and Leaf Area and Their Effects to Ripening Rate During Mature Period of japonica Rice 被引量:4
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作者 LiRong-tian KojimaNobuyoshi 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第2期81-88,共8页
Employing the pot experiment of the complete random block design with 6 replications,four varieties of japonica rice (Fujisaka 5,Honenwase,Akitakomachi and Taichung 65) were used to study the varietal differences in l... Employing the pot experiment of the complete random block design with 6 replications,four varieties of japonica rice (Fujisaka 5,Honenwase,Akitakomachi and Taichung 65) were used to study the varietal differences in leaf nitrogen content(LNC) and leaf area during mature period,their relation and effects to the ripening rate.The results showed that(1) thee were varietal differences in LNC at the heading stage and the LNC decrease rate during the matue period,the high LNC at the heading stage was related to the rapid LNC decrease.(2) There were two phases of the leaf area changing process during the mature period,first was the stable,and second was the decreased phase.There was varietal difference in the critical time of phase 1 and phase 2.The hign leaf area in the phase 1 was in relation to the rapid leaf area decrease in the phase 2.It was not found that there was relation between the leaf quality and quantity.(3)It wa unfavorable to the ripening rate for the high leaf area at the heading stage and the rapid decrease of the leaf area during the mature period.(4)It was put forward that the super high yield rice variety should possess the not very high leaf area and high LNC at the heading stage,slow senescence in the leaf area during the mature period. 展开更多
关键词 japonica rice leaf area leaf nitrogen content(LNC) mature period VARIETY
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Soybean Leaf Morphology Classification Based on FPN-SSD and Knowledge Distillation 被引量:2
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作者 Yu Xiao Fu Li-ren +1 位作者 Dai Bai-sheng Wang Ye-cheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2020年第4期9-17,共9页
Soybean leaf morphology is one of the most important morphological and biological characteristics of soybean.The germplasm gene differences of soybeans can lead to different phenotypic traits,among which soybean leaf ... Soybean leaf morphology is one of the most important morphological and biological characteristics of soybean.The germplasm gene differences of soybeans can lead to different phenotypic traits,among which soybean leaf morphology is an important parameter that directly reflects the difference in soybean germplasm.To realize the morphological classification of soybean leaves,a method was proposed based on deep learning to automatically detect soybean leaves and classify leaf morphology.The morphology of soybean leaves included lanceolate,oval,ellipse and round.First,an image collection platform was designed to collect images of soybean leaves.Then,the feature pyramid networks–single shot multibox detector(FPN-SSD)model was proposed to detect the top leaflets of soybean leaves on the collected images.Finally,a classification model based on knowledge distillation was proposed to classify different morphologies of soybean leaves.The obtained results indicated an overall classification accuracy of 0.956 over a private dataset of 3200 soybean leaf images,and the accuracy of classification for each morphology was 1.00,0.97,0.93 and 0.94.The results showed that this method could effectively classify soybean leaf morphology and had great application potential in analyzing other phenotypic traits of soybean. 展开更多
关键词 leaf morphology classification feature pyramid networks-single shot multibox detector(FPN-SSD) knowledge distillation top leaflet detection
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对密钥托管系统中LEAF结构的研究
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作者 龙宇 曹珍富 《计算机工程》 CAS CSCD 北大核心 2005年第12期156-157,160,共3页
分析了目前各种门限密钥托管体制中的法律实施访问域(LawEnforcementAccessField,LEAF)的结构,对它们进行了攻击。结果证明这些LEAF结构都不能避免LEAF反馈攻击或阈下信道攻击。最后提出了一种可以防止阈下信道攻击的LEAF结构。
关键词 leaf 密钥托管 门限密码学 阈下信道攻击
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Effects of Irrigation Schedules on Photosynthetic Carbon Assimilation of Winter Wheat (Triticum aestivum L.) in North China Plain:from Leaf to Population
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作者 Liu Li-Ping Ouyang Zhu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第4期20-29,共10页
A field experiment was conducted to elucidate the regulation mechanism of different irrigation schedules on population photosynthetic of winter wheat. The experiment included five irrigation schedules, such as no irri... A field experiment was conducted to elucidate the regulation mechanism of different irrigation schedules on population photosynthetic of winter wheat. The experiment included five irrigation schedules, such as no irrigation (W0), irrigation once at jointing (W1j) or at booting (W1b), irrigation twice at jointing and booting (W2), and irrigation three times at jointing, booting and grain-filling (W3) and three planting densities, such as 180 (D1), 300 (D2) and 450 (D3) seedlings per square meter. The results indicated that irrigation significantly improved population photosynthesis. The relationship between population photosynthesis and irrigation time/volume was to some extent parabolic. Improvements in population photosynthesis (resulting from more irrigation time/volume) were mainly related to increase in leaf area index and population light interception. Population photosynthesis exhibited a significantly negative correlation with canopy light transmittance. Population photosynthesis at grain filling stage was significantly positively correlated with dry matter accumulation at post-anthesis and grain yield. Main effects and partial correlation analysis showed that population photosynthesis of W0, W1j, W1b and W3 were regulated by canopy light transmittance and leaf area. On the other hand, population photosynthesis of W2 was mainly influenced by flag leaf photosynthetic rate. On this basis, planting 300 seedlings per square meter was the optimum combination. The combination of W2D2 increased population photosynthesis during mid-late growth stages and extended high population photosynthesis duration, which ultimately increased grain yield. 展开更多
关键词 population photosynthesis leaf photosynthesis leaf area index canopy light transmittance dry matter accumulation at post-anthesis grain yield irrigating schedule
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Soil Chemical and Biological Property Associated with Walnut(Juglans sigillata Dode) Leaf Decomposition
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作者 Ma Hong-ye Pan Xue-jun +1 位作者 Zhang Wen-e Liu Mao-qiao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第4期26-39,共14页
Plant residue application is an important way to maintain soil productivity. In order to determine whether walnut leaf can be returned to soil or not and get the conditions of efficient decomposition, the effect of wa... Plant residue application is an important way to maintain soil productivity. In order to determine whether walnut leaf can be returned to soil or not and get the conditions of efficient decomposition, the effect of walnut (Juglans sigillata Dode) leaf decomposition under various conditions (different temperatures, durations and leaf-soil ratios) upon soil chemicals and biological properties were analyzed. Compared with the original soil, adding walnut leaf to soil could decrease soil pH, increase EC, nutrient contents, microbial quantity and enzyme activities. Total nitrogen, total organic carbon and organic matter increased with the increasing of decomposition duration, temperature and leaf-soil ratio. Enzyme activities changed with different decomposition conditions, but the highest activities of alkaline phosphatase and catalase were associated with the lower temperature (15℃), the highest concentration (10 : 100) and the shortest duration (0 day). Walnut leaves decomposition for 20 or 30 days at 15℃ and with 10 : 100 ratio significantly promoted bacteria, fungi and the total microbial quantity. Walnut leaves can be returned to soil because their decomposition could improve relevant indicators of soil fertility, decomposition conditions as shorter durations (20 days), lower temperature ( 15 ℃) and higher concentrations of leaves ( 10 : 100) were the more effective decomposition conditions for walnut leaves. 展开更多
关键词 walnut leaf temperature leaf-soil ratio decomposition duration soil fertility
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一个水稻“斑马叶”叶色突变体基因zebra leaf2(zl2)的图位克隆 被引量:10
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作者 刘胜 魏祥进 +2 位作者 邵高能 唐绍清 胡培松 《中国水稻科学》 CAS CSCD 北大核心 2013年第3期231-239,共9页
从粳稻品种Asominori组培后代中获得一个稳定遗传的黄绿相间叶色突变体(zebra leaf 2,zl2)。该突变体在苗期表现为黄绿相间的斑马状,分蘖后期斑马叶性状逐渐减弱,到抽穗期叶片逐渐变为淡黄色。与野生型相比,zl2在3叶期、分蘖盛期、抽穗... 从粳稻品种Asominori组培后代中获得一个稳定遗传的黄绿相间叶色突变体(zebra leaf 2,zl2)。该突变体在苗期表现为黄绿相间的斑马状,分蘖后期斑马叶性状逐渐减弱,到抽穗期叶片逐渐变为淡黄色。与野生型相比,zl2在3叶期、分蘖盛期、抽穗期及成熟期叶片的叶绿素、类胡萝卜素含量显著降低,成熟后其结实率、千粒重、株高也显著下降。电镜观察结果显示,苗期zl2叶片黄色部分叶肉细胞中叶绿体显微结构发生了明显的异常,而绿色部分与野生型基本一致。遗传分析结果表明,zl2突变性状受一对隐性核基因控制。从zl2与籼稻品种南京11衍生的F2群体中挑选1607株表现为突变性状的分离单株,最终将该突变基因定位于第11染色体约164.3kb的区域内。基因预测表明该区域内存在13个ORFs,其中ORF12编码一个类胡萝卜素异构酶,序列分析表明突变体中的该基因第10个内含子与第11外显子的交界处碱基A突变为T,导致cDNA发生错误剪切,缺失4个碱基,产生移码突变,并于第395个氨基酸处提前终止。RT-PCR分析表明,相对野生型在突变体中ZL2的表达量显著下降,同时叶色相关基因PORA、RbcL、RbcS、Cab1、Cab2、psaA、psbA、OsDVR表达量也显著下降,而HEMA1、YGL1、V1、V2、SPP、OsPPR的表达量显著上升。结果表明ZL2在水稻叶绿素合成及叶绿体发育中起着重要作用。 展开更多
关键词 叶色突变体 遗传分析 图位克隆 表达分析 水稻
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Differences in leaf functional traits between exotic and native Compositae plant species 被引量:5
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作者 WANG Cong-yan LIU Jun +1 位作者 ZHOU Jia-wei XIAO Hong-guang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2468-2474,共7页
This study aims to determine the differences in leaf functional traits and phenotypic plasticity of leaf functional traits between exotic and native Compositae plant species. Leaf width of exotic plants was significan... This study aims to determine the differences in leaf functional traits and phenotypic plasticity of leaf functional traits between exotic and native Compositae plant species. Leaf width of exotic plants was significantly lower than that of native species. Leaf length, specific leaf area(SLA), single-leaf wet and dry weights, leaf moisture, and leaf thickness of exotic plants were also lower than those of native species but not significantly. The leaf shape index of exotic plants was higher than that of native species but not significantly. This implies that the relatively low leaf construction cost for exotic plants may play an important role in the success of their invasions. The higher leaf shape index and lower leaf width of exotic plants can enhance the efficiency of resource capture(especially sunlight capture) via adjustments to leaf shape and size, thereby increasing the survival of exotic plants. The plasticity indices of single-leaf wet weight and leaf thickness of exotic plants were significantly lower than those of native species. The lower phenotypic plasticity of single-leaf wet weight and leaf thickness of exotic plants may be the result of a cost to plasticity. That is, if the plasticity is too high, the fitness of plant species might be reduced sharply under unfavorable environments. Thus, lower plasticity of leaf functional traits may compensate for the negative impact of adverse environments and stabilize leaf construction costs for exotic plants. Moreover, reduced phenotypic plasticity might be one of the key competitive strategies by which exotic plants successfully invade new habitats. Overall, exotic plants did not always exhibit higher values of leaf functional traits or increased phenotypic plasticity of leaf functional traits compared with native species. 展开更多
关键词 leaf functional TRAITS specific leaf area (SLA) PHENOTYPIC plasticity EXOTIC plants COMPOSITAE
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Variability of leaf functional traits of invasive tree Rhus typhina L. in North China 被引量:5
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作者 WEI Mei WANG Shu +3 位作者 WU Bing-de JIANG Kun ZHOU Jia-wei WANG Cong-yan 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期155-163,共9页
Functional traits, specifically leaf functional traits, are core-topics to explore importance to the invasion success of invasive plant species. This study aims to address the differences in leaf functional traits and... Functional traits, specifically leaf functional traits, are core-topics to explore importance to the invasion success of invasive plant species. This study aims to address the differences in leaf functional traits and their corresponding variability of the invasive tree staghorn sumac Rhus typhina L. with different invasion success, including lower and higher invasion success, in two climatic regions in North China, including a warm temperate region and a cold temperate region. No significant differences were found for leaf functional traits of staghorn sumac across different invasion success. However, the variability of leaf chlorophyll and nitrogen concentrations of staghorn sumac under higher invasion success were approximately 66.023% and 68.615% higher than those under lower invasion success, respectively. The leaf chlorophyll and nitrogen concentrations of staghorn sumac in the warm temperate region were approximately 18.432% and 16.337% higher than those in cold temperate region, respectively. The variability of specific leaf area of staghorn sumac in warm temperate region was approximately 59.802% higher than that in cold temperate region. Accordingly, leaf chlorophyll and N concentrations as well as specific leaf area of staghorn sumac and their corresponding variability may play an essential role in shaping ecological success of studied invader along a climatic gradient. 展开更多
关键词 climatic region invasive tree coefficient of variation VARIABILITY specific leaf area Rhus typhina L.
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Removal of aqueous Ni(Ⅱ) with carbonized leaf powder: Kinetics and equilibrium 被引量:3
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作者 唐强 王恒宇 +1 位作者 唐晓武 王艳 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第4期778-786,共9页
Nickel is a heavy metal which has the potential threaten to human's health and attracts public concern recently. The carbonized leaf powder is expected as suitable adsorbent for Ni(II) removal became of the composi... Nickel is a heavy metal which has the potential threaten to human's health and attracts public concern recently. The carbonized leaf powder is expected as suitable adsorbent for Ni(II) removal became of the composition of some beneficial groups. In this work, carbonized leaf powder was evaluated for its adsorption performance towards Ni(II). According to the results, adsorbent component, dosage, initial solute concentration, solution pH, temperature and contact time can significantly affect the efficiency of Ni(II) removal. Sips model fits the test results best, and the adsorption capacity towards Ni(II) is determined around 37.62 mg/g. The thermodynamic behaviors reveal the endothermic and spontaneous nature of the adsorption. The free adsorption energy (fluctuate around 8 kJ/mol) predicted by D-R model indicates that the adsorption capacity originated from both physical and chemical adsorption. Room temperature (15-25 ℃) is suitable for Ni(II) removal as well as low energy consumption for temperature enhancement. Further conclusions about the mechanism of chemical adsorption are obtained through analysis of the FT-IR test and XRD spectra, which indicates that the adsorption process occurs predominantly between amine, carbonate, phosphate and nickel ions. 展开更多
关键词 carbonized leaf powder Ni(lI) physical adsorption chemical adsorption mechanism
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Physiology and Biochemistry Changes of Euphorbia pulcherrima During Leaf Color Transformation 被引量:2
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作者 WANG Lijuan,SUN Meiqing,and NIU De College of Life Sciences,Northeast Agricultural University,Harbin 150030,China 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第2期48-54,共7页
Reasons for the color change of E.pulcherrima were studied with physiological and biochemical paraments such as: chlorophyll,carotenoids,anthocyanin,Phenylalanine ammonia-lyase (PAL),pH of cell sap in leaves and solub... Reasons for the color change of E.pulcherrima were studied with physiological and biochemical paraments such as: chlorophyll,carotenoids,anthocyanin,Phenylalanine ammonia-lyase (PAL),pH of cell sap in leaves and soluble sugar content etc.The results showed that during the period of the leaf color transmittion of E.pulcherrima,the contents of plastid pigment,soluble sugar and pH of cells sap in leaves showed a high-low-high dynamic change,while the contents of anthocyanin and PAL activity showed the low-high... 展开更多
关键词 Euphorbia pulcherrim Willd CHLOROPHYLL ANTHOCYANIN soluble sugar PAL leaf color
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钢板弹簧建模模块LeafSpring的研究及其应用 被引量:7
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作者 李杰 朱毅杰 刘煜 《科学技术与工程》 2011年第30期7555-7559,7569,共6页
LeafSpring是ADAMS中的一个专用模块,应用其可以快速建立钢板弹簧多体动力学模型。为更好应用LeafSpring,总结了其主要特点,分析了其建模基本原理,说明了其建模步骤。应用LeafSpring,在ADAMS/Car中建立了2片簧钢板弹簧多体动力学模型。... LeafSpring是ADAMS中的一个专用模块,应用其可以快速建立钢板弹簧多体动力学模型。为更好应用LeafSpring,总结了其主要特点,分析了其建模基本原理,说明了其建模步骤。应用LeafSpring,在ADAMS/Car中建立了2片簧钢板弹簧多体动力学模型。通过对模型的必要修改,实现了钢板弹簧垂向刚度特性的仿真测试。通过与实际钢板弹簧刚度特性比较,验证了所建模型的有效性。 展开更多
关键词 ADAMS 钢板弹簧 建模模板 多体动力学模型
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Research Progress on Northern Leaf Blight in Corn 被引量:2
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作者 ZHAO Yingnan WANG Zhenhua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2009年第2期66-71,共6页
The northem corn leaf blight is one of the most serious diseases in maize production. The research progress on etiology, generation law and control strategy, antigen identification, resistance mechanism and inheritanc... The northem corn leaf blight is one of the most serious diseases in maize production. The research progress on etiology, generation law and control strategy, antigen identification, resistance mechanism and inheritance of this disease was discussed. And the research work which should be enhanced in China was pointed out, such as mechanism of resistance inheritance, developing function marker, gene mining, screening resistance resource and dominant physiological race in different areas. 展开更多
关键词 CORN northern leaf blight PROGRESS
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Research on Rice Leaf Disease Recognition Based on BP Neural Network 被引量:1
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作者 Shen Wei-zheng Guan Ying +1 位作者 Wang Yan Jing Dong-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2019年第3期75-86,共12页
To solve the problem of mistake recognition among rice diseases, automatic recognition methods based on BP(back propagation) neural network were studied in this paper for blast, sheath blight and bacterial blight. Cho... To solve the problem of mistake recognition among rice diseases, automatic recognition methods based on BP(back propagation) neural network were studied in this paper for blast, sheath blight and bacterial blight. Chose mobile terminal equipment as image collecting tool and built database of rice leaf images with diseases under threshold segmentation method. Characteristic parameters were extracted from color, shape and texture. Furthermore, parameters were optimized using the single-factor variance analysis and the effects of BP neural network model. The optimization would simplify BP neural network model without reducing the recognition accuracy. The finally model could successfully recognize 98%, 96% and 98% of rice blast, sheath blight and white leaf blight, respectively. 展开更多
关键词 rice leaf disease recognition FEATURE extraction optimization o f CHARACTERISTIC paramete BP NEURAL network
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Effect and mechanism of persimmon leaf flavonoid treatment of experimental oral ulcer 被引量:1
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作者 WANG Shuo ZHANG Yong-li HAO Mai-ling 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第5期486-486,共1页
OBJECTIVE To explore the therapeutic effect and its mechanism of persimmon leaf flavonoids(PLF) on rats with oral ulcer. METHODS The oral ulcer model was induced by acetic acid,was used for intervention of Guilin wate... OBJECTIVE To explore the therapeutic effect and its mechanism of persimmon leaf flavonoids(PLF) on rats with oral ulcer. METHODS The oral ulcer model was induced by acetic acid,was used for intervention of Guilin watermelon frost and different dose(20,40 and 80 mg·kg^(-1)) of PLF.Ulcer area was calculated on the fourth and the seventh day after injury; the changes of superoxide dismutase(SOD) and malondialdehyde(MDA) in serum and ulcer tissues were observed; the level of tumor necrosis factor alpha(TNF-alpha) in ulcer tissue was measured. To observe the pathological morphological changes of H-E staining. RESULTS Guilin watermelon frost and PLF(40 and 80 mg·kg^(-1))can reduce the ulcer area(P<0.05); PLF(20,40 and 80 mg·kg^(-1)) can increase the activity of SOD and decrease the content of MDA in serum and ulcer tissue(P<0.05); Guilin watermelon frost and PLF could significantly decrease the levels of TNF-alpha in ulcer tissue(P<0.05),and improve the inflammatory infiltration of ulcer tissue. CONCLUSION PLF has certain therapeutic effects on oral ulcer induced by acetic acid,and the mechanism may be related to improve oxidative damage and reduce inflammatory reaction. 展开更多
关键词 persimmon leaf flavonoids oral ulcer oxidative stress INFLAMMATION
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