基于WF的杉木人工林交互式疏伐可视化模拟技术

以湖南攸县黄丰桥国有林场为试验区,以杉木人工林为试验对象,测定林木胸径、树高、冠幅等测树因子及林木位置信息。利用WF技术,在定义林分生长模型、林分结构分析与林分疏伐模型等5种活动的基础上,利用人机交互方式,以图形形式建立了林分生长、林分结构与林分疏伐间交互的可视化工作流模型,实现了林分交互式疏伐可视化模拟。采用GDI+绘图技术与MOGRE渲染引擎技术,实现了林分结构、林分2维状态与林分3维场景的可视化模拟。结果表明:林分生长、林分结构与林分疏伐间的交互关系得到了直观的可视化模拟,此方法面向经营者具有可操作性强的特点。林分疏伐前后的林分结构、2维状态与3维场景得到了形象与逼真的模拟。应用交互式疏伐可视化模拟技术,可实现林分疏伐过程、效果以及林分未来状态的可视化模拟,实现对林分疏伐的实时监管,提高林分疏伐数字化管理水平。     

基于CiteSpace的氮沉降知识图谱计量分析

客观分析国内氮沉降研究现状,总结现阶段研究的重点与薄弱点,旨在为氮沉降的科研工作者与决策者提供数据参考.以"氮沉降"为主题词,从CNKI数据库中得到2009-2019年发表的相关文献754篇,运用CiteSpace知识图谱分析工具对关键词、作者、机构进行可视化分析,并对氮沉降的研究进展、发展趋势和资助基金等方面进行相关...     

A high-resolution map of the rice blast resistance gene Pi15 constructed by sequence-ready markers

The gene Pi15 for resistance of rice to Magnaporthe grisea was previously mapped to a ≈0.7-cM region on chromosome 9. To further define the chromosomal region of the Pi15 locus, a contig spanning the locus was constructed, in silico , through bioinformatics analysis using a reference sequence of the cultivar 'Nipponbare'. One simple sequence repeat marker adopted from the International Rice Microsatellite Initiative and six candidate resistance gene (CRG) markers, developed from gene annotation of the reference sequence of the contig, were used for linkage analysis in a mapping population consisting of 504 extremely susceptible F₂ plants. The Pi15 locus was delimited to a ≈0.5-cM region flanked by the markers CRG5 and CRG2 and co-segregated with the markers BAPi15₇₈₂, CRG3 and CRG4, which was physically converted to a 44-kb interval.     

Genetic mapping of AFLP markers in Japanese bunching onion (<Emphasis Type="Italic">Allium fistulosum</Emphasis>)

Summary The first genetic linkage map of Japanese bunching onion (Allium fistulosum) based primarily on AFLP markers was constructed using reciprocally backcrossed progenies. They were 120 plants each of (P₁)BC₁ and (P₂)BC₁ populations derived from a cross between single plants of two inbred lines: D1s-15s-22 (P₁) and J1s-14s-20 (P₂). Based on the (P₂)BC₁ population, a linkage map of P₁ was constructed. It comprises 164 markers – 149 amplified fragment length polymorphisms (AFLPs), 2 cleaved amplified polymorphic sequences (CAPSs), and 12 simple sequence repeats (SSRs) from Japanese bunching onion, and 1 SSR from bulb onion (A. cepa) – on 15 linkage groups covering 947 centiMorgans (cM). The linkage map of P₂ was constructed with the (P₁)BC₁ population and composed of 120 loci – 105 AFLPs, 1 CAPS, and 13 SSRs developed from Japanese bunching onion and 1 SSR from bulb onion – on 14 linkage groups covering 775 cM. Both maps were not saturated but were considered to cover the majority of the genome. Nine linkage groups in P₂ map were connected with their counterparts in P₁ map using co-dominant anchor markers, 13 SSRs and 1 CAPS.     

Molecular markers linked to rhizomania resistance in sugar beet, Beta vulgaris, from two different sources map to the same linkage group

Rhizomania, one of the most important diseases of sugar beet, is caused by beet necrotic yellow vein virus, a Furovirus vectored by the fungus Polymyxa betae Keskin. Reduction of the production losses caused by this disease can only be achieved by using tolerant cultivars. The objective of this study was the identification and mapping of random amplified polymorphic DNA (RAPD) markers linked to a rhizomania resistance gene. The RAPD markers were identified using bulked segregant analysis in a segregating population of 62 individuals derived by intercrossing plants of the resistant commercial hybrid GOLF, and the resistance locus was positioned in a molecular marker linkage map made with a different population of 50 GOLF plants. The resistance locus, Rr1, was mapped to linkage group III of our map of Beta vulgaris L. ssp. vulgaris, which consisted of 76 RAPDs, 20 restriction fragment length polymorphisms (RFLPs), three sequence characterized amplified regions (SCARs) and one sequence tagged site (STS). In total, 101 molecular markers were mapped over 14 linkage groups which spanned 688.4 cM with an average interval length of 8.0 cM. In the combined map, Rr1 proved to be flanked by the RAPD loci RA411₁₈₀₀ and AS7₁₁₀₀ at 9.5 and 18.5cM, respectively. Moreover, in our I₂ population, we found that a set of markers shown by Barzen et al. (1997) to be linked to the ‘Holly’ type resistance gene was also linked to the ‘GOLF’-type resistance gene. These results appeared to indicate that the rhizomania resistance gene present in the GOLF hybrid could be the same gene underlying resistance in ‘Holly’-based resistant genotypes. Two other explanations could be applied: first, that two different alleles at the same locus could have been selected; second, that two different genes at two different but clustered loci underwent the selection process.     

空气负(氧)离子研究的知识图谱

归纳空气负(氧)离子研究进展和前沿热点,旨在为未来研究提供参考.基于Web of Science核心数据库以air negative oxygen ion为检索对象,获取2002-2019年收录的空气负(氧)离子文献,并通过知识图谱展现18年间其发展历程.结果 表明,2002-2019年Web of Science...     

实例教学法在建筑电气施工图识图教学中的运用--以人为本，学以致用

文章针对识图教学过程中运用实例教学的重要性进行阐述,并针对实例教学法在建筑电气施工识图教学中的应用加以探讨,以提供理论参考。     

离心泵整体叶轮流道数控加工误差的仿真

对数控加工所获得的叶轮流道的加工误差进行仿真。首先对刀位轨迹线进行归一化处理,以此计算出脊棱高度曲线,再采用线性插值的方法得到曲面上采样点的加工误差。由于自由曲面加工中的刀位点比较密集,本文利用彩色云图将加工误差可视化,完善了对数控加工结果的计算机几何仿真。该算法已在自行研制的叶轮CAM系统中得到验证,并且与实际加工结果一致。     

基于B/S结构的数字地质图元数据信息系统设计与实现

以国土资源环境与区域经济信息系统信息共享元数据内容标准草案(“NREDIS”)为依据,结合ASP.NET技术,利用C#语言,设计了一个基于B/S(浏览器/服务器)结构的数字地质图元数据信息系统。实现了元数据标准的浏览和元数据的输入、查询及维护4大功能。研究成果为国家空间信息基础设施和数字地球的建设提供了一定的理论基础和技术原型,推动了地理空间信息的网络发布和共享。