基于Web of science文献计量分析的青枯病研究进展

为了解青枯病研究领域中领先的科研机构、科研人员及其研究内容，并对未来的发展方向进行预测，以“Ralstonia solanacearum”、“Pseudomonas solanacearum”为主题词，对1985—2019年Web of Science核心数据库进行搜索，共检索到2 987 篇相关文献，并利用CiteSpace软件对所检索的青枯病英文文献进行分析。结果显示:美国、中国、法国和日本发文量较多，并且国家之间多有合作交流；法国国家农业研究院和美国威斯康星大学为该领域顶尖的研究机构，国内领先机构为南京农业大学；青枯病领域发文量较高的作者有Caitilyn Allen、Philippe Prior、Qirong Shen(沈其荣)、Stephane Genin等；通过关键词共现网络和突发性检测分析，明确当前研究热点方向为青枯菌的致病机理、根际微生物生态、植物-病原菌互作机制等。结合文献交叉引用分析推测未来研究方向包括抗病基因与抗病品种以及全球尺度下青枯菌的遗传多样性与致病多样性的挖掘，并通过多组学进一步阐明植物-病原菌互作和调控机制。     

AutoCAD配合ArcGIS在建设项目使用林地现状图制作中的应用

介绍利用ArcGIS软件制作建设项目使用林地现状图的流程。以云南曲靖呈钢钢铁有限公司镍铁高炉及烧结配套技改项目使用林地现状图为例,阐述AutoCAD矢量图形文件导入ArcGIS并校正配位、缩放,dwg格式文件转换为shp格式等一系列制作方法。     

Visual structure of landscapes seen from built environment

Vegetation in cities keeps climate warming down and improves the health of people and ecosystems while making for a pleasant urban setting. Contemporary urban planning promotes sustainable green cities. Green and blue infrastructures, which help maintain an eco-friendly environment, are the primary instruments of this movement. This paper attempts to show the relative weight of plant life (trees, grass, orchards, etc.) seen from buildings in different urban settings (local urban patterns of high or low density of buildings). Landscapes open to view are identified by combining a digital elevation model and an 11-class land-use layer (including buildings, facilities, grey infrastructures, green and blue surfaces) in a computational tool that calculates viewsheds. The results show that vegetation is very much present in urban landscapes. In high-density built areas of city centres, the landscape is varied although not open and is dominated by trees, low-rise residential buildings and grass. Grey infrastructures and bushes are also very common. In low-density built areas the rank order of objects in view is similar but the landscape is more panoramic.     

基于高密度SNP遗传图谱的粳稻芽期耐低温QTL鉴定

水稻直播由于省时、省工和节约成本而备受农户关注。然而,芽期耐冷性不强致使现行推广的许多优良水稻品种不适于直播生产。因此,挖掘鉴定芽期耐冷位点,为后续的辅助育种提供基因资源就日益受到重视。本研究利用丽江新团黑谷和沈农265构建的重组自交系群体及其重测序构建的包含2818个bin标记的遗传图谱对水稻芽期的耐冷性进行QTL定位分析。共检测到5个芽期耐冷QTL,分布在水稻的1号、3号、9号和11号染色体上,增效等位基因均来自耐冷亲本丽江新团黑谷。这些QTL的LOD值的范围从3.05到24.01,表型贡献率为8.0%～53.5%。其中,表型贡献率最大的主效QTL是qCTB11b,位于11号染色体长臂端的21.24 Mb～22.03 Mb之间,物理图谱区间为790 kb。随后利用"选择作图"的策略进行了QTL验证和累加效应分析,明确了可以通过QTL的累加聚合实现芽期耐冷能力的遗传改良,聚合的增效QTL越多,耐冷能力提升越明显。上述研究结果不仅可以增强人们对芽期水稻耐冷能力遗传基础的认识和理解,也可以为后续直播品种的遗传改良提供理论依据和技术指导。     

基于GIS的农田土壤水分状况管理模型及应用

基于GIS开发了土壤水分和土壤电导率的简单专题图及精细专题图模块。简单专题图为运行于农田PDA的嵌入式GIS系统提供采样异常点检查验证;精细专题图为运行于上位机的农田信息处理系统提供信息可视化管理。简单专题图调用GIS组件方法获得并据此建立了采样管理模型;精细专题图中,土壤水分采用克里金插值算法预测的均方根百分比误差（RMSPE）为5.489%;土壤电导率插值模型采用泛克里金算法预测的RMSPE为18.451%。基于精细农田信息专题图,根据特定作物不同生长时期需水量的专家推荐值建立了土壤水分管理模型,利用该模型进行的一次灌溉决策显示,土壤含水率方差从灌溉前的1.9168调整到了灌溉后的0.8906。试验表明,采样管理模型能够指导田间采样,农田水分管理模型能够指导农田灌溉。     

Identification for the stable hot-working parameters of AZ80 magnesium alloy

Several series of billet samples are compressed on physical simulation machine under deformation temperatures 523～673 K and strain rates 0.01～10 s-1, and the true stress-strain data collected result in the performance of calculations for strain rate sensitivity (m-value), power dissipation efficiency (η-value) and instability parameter (ξ-value). A series of 3D surfaces reveal the severe response of m-value to the evolution and coexisting of several deformation mechanisms induced by the enhanced effect of stress, temperature, strain rate and strain, from which the unstable deformation parameter regions are identified preliminarily. Furthermore, the maps of power dissipation efficiency are plotted, from which the unstable (η≤0) deformation parameter regions are indentified. Finally, based on the map of instability criterion, stable region (ξ＞0), unstable region (ξ≤-1) and metastable region (-1＜ξ≤0) are clarified clearly. According to the comprehensive identification, the stable deformation parameter regions with higher m-value level and higher η-value level and higher ξ-value level are recommended, while the unstable deformation parameter regions with negative m-value level and negative η-value level and negative ξ-value level should be avoided.     

Prognoses of inlet water quality via QSOM in wastewater treatment processes

A quantum self organizing feature map neural network (QSOM) method is introduced for water quality prediction in activated sludge wastewater treatment processes which includes uncertainty of microbial activity and complexity of biochemical reactions and strong lagging of parameters. This approach quantizes the inlet water quality data corresponding outlet water in abnormal state and makes the quantized data sample as the input of QSOM. The correlation coefficient of the quantum inputs and its weights are calculated as the best inputs matching of network by using quantum gates to update the weights in learning the rules. The experiments illustrate the efficiency of this prediction approach by using operational data of Chongqing Jiguanshi wastewater treatment plant.     

地图空间信息度量方法在地学信息图谱中的应用

研究了将地图空间信息度量方法应用到地学信息图谱及在空间信息度量方法中引入指数信息熵的方法,实例应用证明,运用地图空间信息度量方法与地图信息图谱分析相结合研究信息量是可行的,而且将指数信息熵应用于地图空间信息度量可避免无定义值和零值的出现。