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Hybrid tree guided PatchMatch and quantizing acceleration for multiple views disparity estimation
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作者 张吉光 徐士彪 张晓鹏 《中国体视学与图像分析》 2021年第1期47-61,共15页
Existing stereo matching methods cannot guarantee both the computational accuracy and efficiency for ihe disparity estimation of large-scale or multi-view images.Hybrid tree method can obtain a disparity estimation fa... Existing stereo matching methods cannot guarantee both the computational accuracy and efficiency for ihe disparity estimation of large-scale or multi-view images.Hybrid tree method can obtain a disparity estimation fast with relatively low accuracy,while PatchMatch can give high-precision disparity value with relatively high computational cost.In this work,we propose the Hybrid Tree Guided PatchMatch which can calculate the disparity fast and accurate.Firstly,an initial disparity map is estimated by employing hybrid tree cost aggregation,which is used to constrain the label searching range of the PatchMatch.Furthermore,a reliable normal searching range for each current normal vector defined on the initial disparity map is calculated to refine the PatchMatch.Finally,an effective quantizing acceleration strategy is designed to decrease the matching computational cost of continuous disparity.Experimental results demonstrate that the disparity estimation based on our algorithm is better in binocular image benchmarks such as Middlebury and KITTI.We also provide the disparity estimation results for multi-view stereo in real scenes. 展开更多
关键词 stereo matching multiple views disparity estimation hybrid tree PatchMatch
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Research on the adaptive hybrid search tree anti-collision algorithm in RFID system 被引量:3
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作者 靳晓芳 Liu Mengxuan +2 位作者 Shao Min Jin Libiao Huang Xianglin 《High Technology Letters》 EI CAS 2016年第1期107-112,共6页
Due to more tag-collisions result in failed transmissions,tag anti-collision is a very vital issue in the radio frequency identification(RFID) system.However,so far decreases in communication time and increases in thr... Due to more tag-collisions result in failed transmissions,tag anti-collision is a very vital issue in the radio frequency identification(RFID) system.However,so far decreases in communication time and increases in throughput are very limited.In order to solve these problems,this paper presents a novel tag anti-collision scheme,namely adaptive hybrid search tree(AHST),by combining two algorithms of the adaptive binary-tree disassembly(ABD) and the combination query tree(CQT),in which ABD has superior tag identification velocity and CQT has optimum performance in system throughput and search timeslots.From the theoretical analysis and numerical simulations,the proposed algorithm can colligate the advantages of above algorithms,improve the system throughput and reduce the searching timeslots dramatically. 展开更多
关键词 ANTI-COLLISION adaptive binary-tree disassembly( ABD) hybrid search tree DISCRIMINATION
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Identification of differentially expressed genes associated with bud dormancy release in tree peony(Paeonia suffruticosa) by suppression subtractive hybridization 被引量:2
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作者 HUANG Xin ZHENG Guo-sheng +1 位作者 DAI Si-lan GAI Shu-peng 《Forestry Studies in China》 CAS 2008年第2期88-94,共7页
A subtractive cDNA library was developed to study genes associated with bud dormancy release in tree peonies. In order to identify genes that are highly expressed in buds released from dormancy, 588 clones were examin... A subtractive cDNA library was developed to study genes associated with bud dormancy release in tree peonies. In order to identify genes that are highly expressed in buds released from dormancy, 588 clones were examined by differential screening. Of these, 185 clones were selected to be sequenced. A total of 37 unique sequences were obtained of which only 31 sequences have matches in the NCBI database or the Arabidopsis thaliana protein database. Semi-quantitative RT-PCR was used to confirm further the expression profiles for 12 transcripts identified within the subtractive cDNA library. Gene ontology analyses indicated that many of the different genes identified have unknown or hypothetical functions while it is speculated that other genes play different mo- lecular roles. In our study, genes involved in bud dormancy release were growth-related or stress-responsive, while low-temperature-induced ribosomal proteins may also play a role in bud dormancy release. Our results provide interesting information for further understanding of the molecular mechanism of bud dormancy release in tree peonies. 展开更多
关键词 cDNA clone DORMANCY subtractive hybridization tree peony (Paeonia suffruticosa)
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基于GPU的HPGB+-Tree索引
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作者 刘军 冷芳玲 李宇轩 《计算机与数字工程》 2021年第12期2490-2495,共6页
索引作为加速数据库查询的一种成熟技术,始终受限于CPU的内存带宽与架构的发展,因此无法在性能上实现质的飞跃。所以使用GPU赋能索引技术来辅助数据库执行查询任务是势在必行的。因此,针对异构环境下索引结构的适应性以及现有GPU索引受... 索引作为加速数据库查询的一种成熟技术,始终受限于CPU的内存带宽与架构的发展,因此无法在性能上实现质的飞跃。所以使用GPU赋能索引技术来辅助数据库执行查询任务是势在必行的。因此,针对异构环境下索引结构的适应性以及现有GPU索引受限于显存容量导致扩展性不够等问题,提出了一种CPU与GPU协同处理的HPGB+-Tree索引算法。该算法以混合架构的方式重新构建索引结构,使其完全适应GPU的硬件特性,突破CPU内存带宽受限和GPU内存容量受限的双重难关。HPGB+-Tree索引不仅解决了索引异构问题,还充分利用两大硬件平台各自的优势加速基于索引的相关操作。在不同数据量与不同任务规模下对算法的性能进行了评估,实验结果表明,该算法在内核占用率与程序执行速度两个方面都极具优势,在性能上处于领先地位。 展开更多
关键词 图形处理器 CUDA HPGB+-tree索引 混合架构
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Decision tree and deep learning based probabilistic model for character recognition 被引量:6
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作者 A.K.Sampath Dr.N.Gomathi 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第12期2862-2876,共15页
One of the most important methods that finds usefulness in various applications, such as searching historical manuscripts, forensic search, bank check reading, mail sorting, book and handwritten notes transcription, i... One of the most important methods that finds usefulness in various applications, such as searching historical manuscripts, forensic search, bank check reading, mail sorting, book and handwritten notes transcription, is handwritten character recognition. The common issues in the character recognition are often due to different writing styles, orientation angle, size variation(regarding length and height), etc. This study presents a classification model using a hybrid classifier for the character recognition by combining holoentropy enabled decision tree(HDT) and deep neural network(DNN). In feature extraction, the local gradient features that include histogram oriented gabor feature and grid level feature, and grey level co-occurrence matrix(GLCM) features are extracted. Then, the extracted features are concatenated to encode shape, color, texture, local and statistical information, for the recognition of characters in the image by applying the extracted features to the hybrid classifier. In the experimental analysis, recognition accuracy of 96% is achieved. Thus, it can be suggested that the proposed model intends to provide more accurate character recognition rate compared to that of character recognition techniques used in the literature. 展开更多
关键词 GREY level CO-OCCURRENCE matrix FEATURE HISTOGRAM oriented GABOR gradient FEATURE hybrid CLASSIFIER holoentropy enabled decision tree CLASSIFIER
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Multicast Routing Based on Hybrid Genetic Algorithm
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作者 曹元大 蔡刿 《Journal of Beijing Institute of Technology》 EI CAS 2005年第2期130-134,共5页
A new multicast routing algorithm based on the hybrid genetic algorithm (HGA) is proposed. The coding pattern based on the number of routing paths is used. A fitness function that is computed easily and makes algorith... A new multicast routing algorithm based on the hybrid genetic algorithm (HGA) is proposed. The coding pattern based on the number of routing paths is used. A fitness function that is computed easily and makes algorithm quickly convergent is proposed. A new approach that defines the HGA's parameters is provided. The simulation shows that the approach can increase largely the convergent ratio, and the fitting values of the parameters of this algorithm are different from that of the original algorithms. The optimal mutation probability of HGA equals 0.50 in HGA in the experiment, but that equals 0.07 in SGA. It has been concluded that the population size has a significant influence on the HGA's convergent ratio when it's mutation probability is bigger. The algorithm with a small population size has a high average convergent rate. The population size has little influence on HGA with the lower mutation probability. 展开更多
关键词 multicast routing hybrid genetic algorithm(HGA) simulation algorithm Steiner tree
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Useful life prediction using a stochastic hybrid automata model for an ACS multi-gyro subsystem 被引量:1
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作者 CHENG Yuehua JIANG Liang +1 位作者 JIANG Bin LU Ningyun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期154-166,共13页
A useful life prediction method based on the integration of the stochastic hybrid automata(SHA) model and the frame of the dynamic fault tree(DFT) is proposed. The SHA model can incorporate the orbit environment, work... A useful life prediction method based on the integration of the stochastic hybrid automata(SHA) model and the frame of the dynamic fault tree(DFT) is proposed. The SHA model can incorporate the orbit environment, work modes, system configuration, dynamic probabilities and degeneration of components,as well as spacecraft dynamics and kinematics. By introducing the frame of DFT, the system is classified into several layers, and the problem of state combination explosion is artfully overcome.An improved dynamic reliability model(DRM) based on the Nelson hypothesis is investigated to improve the defect of cumulative failure probability(CFP), which is used to address the failure probability of components in the SHA model. The simulation using the Monte-Carlo method is finally conducted on two satellites, which are deployed with the same multi-gyro subsystem but run on different orbits. The results show that the predicted useful life of the attitude control system(ACS) with consideration of abrupt failure,degradation, and running environment is quite different between the two satellites. 展开更多
关键词 useful life prediction STOCHASTIC hybrid AUTOMATA (SHA) multi-gyro SUBSYSTEM DYNAMIC fault tree (DFT) DYNAMIC reliability.
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Hybrid Cartesian Grid Method for Moving Boundary Problems
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作者 Shen Zhiwei Zhao Ning 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第1期37-44,共8页
A hybrid Cartesian structured grid method is proposed for solving moving boundary unsteady problems. The near body region is discretized by using the body-fitted structured grids, while the remaining computational dom... A hybrid Cartesian structured grid method is proposed for solving moving boundary unsteady problems. The near body region is discretized by using the body-fitted structured grids, while the remaining computational domain is tessellated with the generated Cartesian grids. As the body moves, the structured grids move with the body and the outer boundaries of inside grids are used to generate new holes in the outside adaptive Cartesian grid to facilitate data communication. By using the alternating digital tree (ADT) algorithm, the computational time of hole-cutting and identification of donor cells can be reduced significantly. A compressible solver for unsteady flow problems is developed. A cell-centered, second-order accurate finite volume method is employed in spatial discreti- zation and an implicit dual-time stepping low-upper symmetric Gauss-Seidei (LU-SGS) approach is employed in temporal discretization. Geometry-based adaptation is used during unsteady simulation time steps when boundary moves and the flow solution is interpolated from the old Cartesian grids to the new one with inverse distance weigh- ting interpolation formula. Both laminar and turbulent unsteady cases are tested to demonstrate the accuracy and efficiency of the proposed method. Then, a 2-D store separation problem is simulated. The result shows that the hybrid Cartesian grid method can handle the unsteady flow problems involving large-scale moving boundaries. 展开更多
关键词 hybrid Cartesian grid l moving boundary alternating digital tree (ADT) algorithm unsteady flow
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面向科技文献多维语义组织的混合倒排索引构建方法
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作者 张敏 李唯 范青 《现代情报》 CSSCI 北大核心 2024年第2期107-114,129,共9页
[目的/意义]为满足科研人员对科技文献内部细粒度语义信息进行高效查询的迫切需求,前期研究提出了面向科技文献的多维语义索引体系,然而基于HashMap的常见倒排索引会导致查询效率低下。本文旨在通过面向不同维度语义特征建立混合倒排索... [目的/意义]为满足科研人员对科技文献内部细粒度语义信息进行高效查询的迫切需求,前期研究提出了面向科技文献的多维语义索引体系,然而基于HashMap的常见倒排索引会导致查询效率低下。本文旨在通过面向不同维度语义特征建立混合倒排索引,以改进语义查询性能。[方法/过程]本文以Treap、B+树等多种数据结构探索适合不同语义维度的倒排索引构建方法,并将其组合形成多种适用于科技文献多维语义组织的混合倒排索引构建方法,并通过对比实验,在排序查询和布尔查询条件下分析验证不同类型倒排索引构建方法的查询性能。[结果/结论]实验结果表明,组合形成的8种混合倒排索引构建方法中,表2所示的C3(HHHB)被证明在排序查询条件下具有最高的效率,而C4(TTTB)则在布尔查询条件下被证明最为高效。本文的方法能有效解决单一索引结构导致的查询效率问题。 展开更多
关键词 科技文献 语义组织 混合倒排索引 HashMap Treap B+树
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Predicting the Results of RNA Molecular Specific Hybridization Using Machine Learning 被引量:3
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作者 Weijun Zhu Xiaokai Liu +1 位作者 Mingliang Xu Huanmei Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1384-1396,共13页
Ribonucleic acid(RNA)hybridization is widely used in popular RNA simulation software in bioinformatics.However limited by the exponential computational complexity of combin atorial problems,it is challenging to decide... Ribonucleic acid(RNA)hybridization is widely used in popular RNA simulation software in bioinformatics.However limited by the exponential computational complexity of combin atorial problems,it is challenging to decide,within an acceptable time,whether a specific RNA hybridization is effective.We hereby introduce a machine learning based technique to address this problem.Sample machine learning(ML)models tested in the training phase include algorithms based on the boosted tree(BT)random forest(RF),decision tree(DT)and logistic regression(LR),and the corresponding models are obtained.Given the RNA molecular coding training and testing sets,the trained machine learning models are applied to predict the classification of RNA hybridization results.The experiment results show that the op timal predictive accuracies are 96.2%,96.6%,96.0%and 69.8%for the RF,BT,DT and LR-based approaches,respectively,un der the strong constraint condition,compared with traditiona representative methods.Furthermore,the average computation efficiency of the RF,BT,DT and LR-based approaches are208679,269756,184333 and 187458 times higher than that o existing approach,respectively.Given an RNA design,the BT based approach demonstrates high computational efficiency and better predictive accuracy in determining the biological effective ness of molecular hybridization. 展开更多
关键词 Biological effectiveness boosted tree(BT) decision tree(DT) random forest(RF) RNA design SPECIFIC hybridIZATION LOGISTIC regression(LR)
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编译型嵌入式Python的设计与实现 被引量:1
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作者 李春亭 王宜怀 +1 位作者 施连敏 张露 《计算机工程与设计》 北大核心 2024年第1期79-87,共9页
针对面向微控制器的解释型MicroPython具有实时性弱、占用存储空间大和可移植性较差等问题,提出一种将Python语言转化为C++语言并将构件层与应用层分离的编译型嵌入式Python方案,设计基于抽象语法树及类型注释的源码映射机制。在此基础... 针对面向微控制器的解释型MicroPython具有实时性弱、占用存储空间大和可移植性较差等问题,提出一种将Python语言转化为C++语言并将构件层与应用层分离的编译型嵌入式Python方案,设计基于抽象语法树及类型注释的源码映射机制。在此基础上,设计嵌入式Python编译器,实现集成开发环境AHL-GEC-IDE(for Python版),完成Python源文件的编辑、编译、链接和下载。实践结果表明,该编译型Python方案可行,为嵌入式人工智能领域提供了一种实时性较高、编辑编译方便、可移植性较强的编译型Python集成开发环境。 展开更多
关键词 编译型嵌入式Python 微型Python解释器 微控制器 抽象语法树 类型注释 混合编程 可移植性
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大花黄牡丹与日本牡丹杂交试验
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作者 唐英 王忠斌 +2 位作者 方亮媛 邢震 许建昌 《广西林业科学》 2024年第3期339-343,共5页
大花黄牡丹(Paeonia ludlowii)是我国9个牡丹原生种之一,为西藏特有植物。挖掘大花黄牡丹的基因潜能,筛选优质杂交父本,可为进一步培育株型高大的黄色系牡丹新品种提供实践依据。以大花黄牡丹为母本,‘皇嘉门’('Kokamon')、‘... 大花黄牡丹(Paeonia ludlowii)是我国9个牡丹原生种之一,为西藏特有植物。挖掘大花黄牡丹的基因潜能,筛选优质杂交父本,可为进一步培育株型高大的黄色系牡丹新品种提供实践依据。以大花黄牡丹为母本,‘皇嘉门’('Kokamon')、‘芳纪’('Hoki')、‘岛大臣’('Shimadaijin')、‘日暮’('Higurashi')、‘新日月锦’('Shin-jitsugetu')、‘八千代椿’('Yachiyotsubaki')和‘花竞’('Hanakisoi')7个日本牡丹品种为父本进行杂交,测定结实率、饱满种子率和出苗率等指标。结果表明,从109朵杂交授粉花朵中,获得杂交种子219粒,饱满种子22粒,出苗10株,平均结实率为13.61%,平均饱满种子率为10.05%,平均出苗率为4.57%。7个日本牡丹品种与大花黄牡丹杂交均具有一定亲和性,杂交亲和性表现为‘新日月锦’>‘皇嘉门’>‘八千代椿’>‘岛大臣’>‘花竞’>‘芳纪’>‘日暮’。结合结实率和出苗率,以‘新日月锦’和‘八千代椿’2个品种为父本,杂交效果较佳。 展开更多
关键词 杂交育种 大花黄牡丹 日本牡丹品种
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基于改进决策树的不平衡数据集分类算法研究
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作者 陈婷 谢志龙 《计算机仿真》 2024年第8期497-501,共5页
不平衡数据集中各类样本数量不均,导致分类模型难以训练。针对不平衡数据分类模型稳定性差,准确率低的问题,提出一种基于改进C4.5决策树数据分类算法,通过融合SMOTE优化采样算法,构建出N_C4.5-IDC不平衡数据分类模型。模型首先利用K-Me... 不平衡数据集中各类样本数量不均,导致分类模型难以训练。针对不平衡数据分类模型稳定性差,准确率低的问题,提出一种基于改进C4.5决策树数据分类算法,通过融合SMOTE优化采样算法,构建出N_C4.5-IDC不平衡数据分类模型。模型首先利用K-Means聚类对数据集进行状态分布分析,并使用SMOTE采样法进行混合采样,通过增加人为样本点提高少数类样本数,对数据集进行平衡处理;然后对C4.5决策树的核心信息增益率模型进行简化改进,提高特征选择效率,并采用回缩损失对比的方法对决策树进行后剪枝处理,构建单一N_C4.5决策树模型;最后将多组N_C4.5模型进行组合叠加,采用加权处理的方法构建N_C4.5-IDC模型。消融实验数据结果表明:优化策略的叠加能显著提高模型性能指标。对比实验数据结果表明:与基线分类算法相比,所提算法准确率最高达96.81%,召回率提高了6.15%,综合性能上升了5.66%。综上,基于改进C4.5决策树构建的不平衡数据分类模型在平衡数据的同时,提高了分类的稳定性与准确性。 展开更多
关键词 不平衡数据集 决策树混合采样
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不同授粉方式对油用型牡丹结实性影响的研究
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作者 王晓晖 刘红凡 +5 位作者 冀含乐 潘永 马会萍 王二强 薛娴 韩鲲 《特产研究》 2024年第3期64-71,共8页
为提高油用牡丹产量,探索油用牡丹理想授粉方式,选择结实性良好、生长势强且自然花期相遇的常见油用型牡丹品种,开展自交、人工授粉、自然授粉等不同方式的授粉试验,调查其坐果率、结实率、种子千粒重等结实情况和蓇葖果单角大小、质量... 为提高油用牡丹产量,探索油用牡丹理想授粉方式,选择结实性良好、生长势强且自然花期相遇的常见油用型牡丹品种,开展自交、人工授粉、自然授粉等不同方式的授粉试验,调查其坐果率、结实率、种子千粒重等结实情况和蓇葖果单角大小、质量等果荚干物质性状。结果表明,油用型牡丹存在一定自花结实性,自交处理Ⅰ没有结实,处理Ⅱ3个品种结实,处理Ⅲ全部结实,其中‘凤丹白’结实最好,为每个果角0.54粒;将参试的牡丹品种进行4×4人工定向安全双列杂交,所有组合全部结实,平均坐果率高达92%,单果角结实率达到3.87粒,结实率最高的组合为‘凤丹白×景泰蓝’,单果角结实率达到6.96粒;田间自然授粉均有结实,‘凤丹白'结实率最高,3.19粒/个;‘景泰蓝’和‘凤丹白’杂交的种子千粒重较高,达到436.89 g;蓇葖果果荚大小和质量与杂交母本关系较密切,以‘景泰蓝’为母本时表现突出;通过不同授粉方式所对应的坐果率、结实率和复果荚重等指标综合分析,从高到低依次为:人工授粉>自然授粉>自交,母本是影响杂交成功率和果荚性状的重要因素;油用牡丹生产中可通过品种合理搭配间植、相互授粉,如‘景泰蓝’和‘凤丹白’,获得更高种子产量。 展开更多
关键词 油用牡丹 自交 人工授粉 自然授粉 结实性
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基于UMCS树的UML类图的混合相似性度量
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作者 袁中臣 马宗民 《计算机应用》 CSCD 北大核心 2024年第3期883-889,共7页
软件重用是基于给定条件从存储库中检索以前开发的软件产品,检索基于相似性度量。UML(Unified Modeling Language)类图被广泛应用于软件设计,UML类图重用作为软件设计重用的核心而备受关注。因此,对UML类图的相似性开展研究。类图包含... 软件重用是基于给定条件从存储库中检索以前开发的软件产品,检索基于相似性度量。UML(Unified Modeling Language)类图被广泛应用于软件设计,UML类图重用作为软件设计重用的核心而备受关注。因此,对UML类图的相似性开展研究。类图包含语义和结构信息。目前,UML类图的相似性研究主要集中在语义,也有个别讨论结构相似性,但没有考虑将语义和结构相结合。因此,提出一种结合语义和结构的混合相似性度量。鉴于UML类图的非形式化特征,将UML类图转换成图模型,搜索最大公共子图列表,构建了最大公共子图树,提出一个基于最大公共子图序列的混合相似性度量方法。针对概念公共子图和结构公共子图分别定义了语义匹配和结构匹配,并开展了相似性对比和基于相似性的分类质量比较实验,实验结果验证了所提出方法的优势。 展开更多
关键词 UML类图 模型转换 混合相似性 最大公共子图树 语义匹配 结构匹配
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自调整混合树RFID多标签防碰撞算法 被引量:38
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作者 宋建华 郭亚军 +1 位作者 韩兰胜 王志皓 《电子学报》 EI CAS CSCD 北大核心 2014年第4期685-689,共5页
在RFID系统中,阅读器读取标签的效率与解决标签发生碰撞的方法密切相关.目前采用多叉树查询是一种较好的多标签防碰撞方法.它能减少碰撞时隙,再通过额外的查询来减少空闲时隙.但额外的查询也增加了新的开销.本文提出了一个自调整混合树R... 在RFID系统中,阅读器读取标签的效率与解决标签发生碰撞的方法密切相关.目前采用多叉树查询是一种较好的多标签防碰撞方法.它能减少碰撞时隙,再通过额外的查询来减少空闲时隙.但额外的查询也增加了新的开销.本文提出了一个自调整混合树RFID多标签防碰撞算法,该算法根据最高两个碰撞位的特征,在不增加额外查询的条件下,自调整搜索树的叉数,从而避免了一些碰撞时隙和空闲时隙.通过对算法的性能分析和仿真结果可以看到,自调整混合树RFID多标签防碰撞算法具有较少的时间复杂度和通信复杂度,识别效率也明显高于其他多叉树算法. 展开更多
关键词 射频识别 混合树 防碰撞算法
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基于混合模型的落叶松树高生长模型 被引量:11
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作者 陈东升 孙晓梅 李凤日 《东北林业大学学报》 CAS CSCD 北大核心 2013年第10期60-64,共5页
以辽宁省大孤家林场不同种和杂种落叶松试验林为研究对象,应用理查德基础模型构建非线性混合模型,考虑落叶松种和杂种之间的差异为随机效应,采用R软件进行模拟,选择模型收敛及其AIC和BIC值最小的混合模型作为最优模型。在此基础上考虑... 以辽宁省大孤家林场不同种和杂种落叶松试验林为研究对象,应用理查德基础模型构建非线性混合模型,考虑落叶松种和杂种之间的差异为随机效应,采用R软件进行模拟,选择模型收敛及其AIC和BIC值最小的混合模型作为最优模型。在此基础上考虑树高生长数据的时间序列相关性,来提高拟合的精确度,并分析不同种及杂种间树高生长的差异性,以期为建立精细到种的林分生长和收获模型奠定理论基础。结果表明:考虑种间效应的混合模型模拟精度优于传统的回归模型方法,残差分布明显改善;ARMA(2,2)自回归误差结构矩阵模型在解释树高生长的时间序列相关性时不仅提高了混合模型的模拟精度,而且能够很好地表达连续观测数据间误差分布情况;因此混合模型提高了模型的精度和通用性,并且模型中每个参数都有特定的数学含义。通过参数分析得出随机因子对树高生长的影响程度,其中以日81×长白落叶松杂种树高生长表现最具优势。 展开更多
关键词 落叶松人工林 种和杂种 树高生长 混合模型
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杂交鹅掌楸苗期光合特性的研究 被引量:19
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作者 杨秀艳 季孔庶 +1 位作者 王章荣 赖焕林 《西北林学院学报》 CSCD 北大核心 2005年第2期39-43,共5页
本文研究了杂交鹅掌楸、鹅掌楸及北美鹅掌楸家系实生苗的光合特性,并分析了光合指标与生长性状的相关性,结果表明:(1)杂交鹅掌楸为阳性树种,其光饱和点在1200μmol·m-2·s-1以上;(2)正交家系CT01对光强的适应范围较广,对光能... 本文研究了杂交鹅掌楸、鹅掌楸及北美鹅掌楸家系实生苗的光合特性,并分析了光合指标与生长性状的相关性,结果表明:(1)杂交鹅掌楸为阳性树种,其光饱和点在1200μmol·m-2·s-1以上;(2)正交家系CT01对光强的适应范围较广,对光能的利用率较高;回交0家系HCO2具有较低的CO2补偿点,且它们的平均净光合速率(Pn)值较高,认为对于鹅掌楸属树种可以通过杂交,选育高光合能力的杂种后代;(3)在Pn指标上,与鹅掌楸相比多数杂种家系具有明显优势;苗高和地径与单株面积和光合生产率(PP)呈显著或极显著正相关,相关系数分别为0.54069和0.48453,0.57893和0.4535;(4)生长性状与单株叶面积及PP的密切关系说明拥有强大的光合面积是杂交鹅掌楸生长旺盛的重要生理基础,这两个指标可以作为苗期选择的指标。 展开更多
关键词 杂交鹅掌楸 光合特性 变异 相关性
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高光谱遥感数据用于水稻精细分类研究 被引量:19
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作者 张丰 熊桢 寇宁 《武汉理工大学学报》 CAS CSCD 2002年第10期36-39,共4页
根据水稻生长期的高光谱数据的光谱特征 ,设计了一个混合决策树分类算法。该算法的特征波段根据波段间的可分离性决定 ,算法的选择根据实际分类效果决定 ,波段间的可分离性根据各波段均值的归一化距离决定。最后用江苏常州市金坛良种场... 根据水稻生长期的高光谱数据的光谱特征 ,设计了一个混合决策树分类算法。该算法的特征波段根据波段间的可分离性决定 ,算法的选择根据实际分类效果决定 ,波段间的可分离性根据各波段均值的归一化距离决定。最后用江苏常州市金坛良种场的高光谱图象数据做了分类实验 ,取得了测试样本总体分类精度 94 . 展开更多
关键词 高光谱遥感数据 混合决策树 水稻 精细分类
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平邑甜茶与B_9杂种F_1群体部分性状的遗传趋势 被引量:5
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作者 杨锋 张景娥 +4 位作者 伊凯 刘志 荣志祥 王冬梅 闫忠业 《果树学报》 CAS CSCD 北大核心 2010年第3期323-327,共5页
以平邑甜茶与B9为亲本进行杂交,共获得杂交种子2828粒,培育幼苗2198株,筛选红叶杂种苗65株,占总苗数的2.96%;其中49株进入花期。杂种后代的无融合生殖率鉴定为:84.00%~95.06%20株,10.00%~48.00%8株,2.08%~5.00%21株。叶片颜色遗传表... 以平邑甜茶与B9为亲本进行杂交,共获得杂交种子2828粒,培育幼苗2198株,筛选红叶杂种苗65株,占总苗数的2.96%;其中49株进入花期。杂种后代的无融合生殖率鉴定为:84.00%~95.06%20株,10.00%~48.00%8株,2.08%~5.00%21株。叶片颜色遗传表明:无融合生殖型杂种树后代与母株一致性在70.79%~86.54%;有性生殖型的在46.51%~51.72%,推测平邑甜茶的无融合生殖基因对有性生殖基因可能为显性遗传,无融合生殖以质量性状遗传为主,也受数量基因的控制。B9的矮生性状在后代中遗传并分离,其中矮生群体占16.33%,乔化群体占44.90%,B9的矮生基因可以遗传给其无融合生殖型后代,并表现矮生性状。电导法初步鉴定表明,杂种群体具有一定的抗寒性,并且分离不大,平均在-34℃达到半致死伤害,略低于亲中值-35℃,平邑甜茶与B9的抗寒基因具有较强的遗传趋势。 展开更多
关键词 平邑甜茶 B9 遗传趋势 杂种树
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