共查询到19条相似文献，搜索用时 296 毫秒
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地理专家系统的知识表示与知识库组织 总被引：3，自引：0，他引：3
付炜 《干旱区资源与环境》1996,10(3):93-100
本文介绍了地理专家系统的知识表示和知识库组织的基本原理和方法，并以水土保持专家系统为例，阐述了水土保持专家知识的分类分级方法，以及在水土保持专家系统中知识表示的基本规划和知识库中专家知识的组织方式。在知识获取机构中，系统提供了以辅助编辑手段为主，自然语言理解为辅的人机交互界面，从而简化了专家知识的录入过程，提高了系统的工作效率。 相似文献
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随着计算机技术的发展和普及,从70年代开始,国内外就有关于应用计算机鉴定某类生物如植物子实、鱼和病毒等的报道。在昆虫鉴定方面,由于昆虫的种类繁多、鉴定特征复杂,以及昆虫分类学本身还存在许多问题等因素的影响,计算机的应用受到限制,开发的一些计算机系统也 相似文献
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宁夏盐池半荒漠风沙区PRED专家系统总体设计 总被引：1，自引：0，他引：1
本文在分析ＰＲＥＤ生态学原理的基础上对开发盐池县半荒漠风沙区ＥＳ－ＰＲＥＤ专家系统的设计作了简要介绍，阐明了ＥＳ－ＰＲＥＤ专家系统的参数设定，主要功能要求以及界面风格，提出了反向目标推理的系统推理模式与键式咨询路径的系统设计方案。 相似文献
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苹果异形小卷蛾（Thaumatotibia leucotreta）是世界范围内重要的检疫性有害生物,对水果和农作物等生产具有重要影响,并影响国际贸易发展。本研究选用线粒体 COI 基因作为物种鉴定的条形码,结合 GenBank 数据库、BOLD 数据库比对和系统进化树构建,对2014年1月广州白云国际机场口岸入境加纳牛油果中截获的卷蛾科昆虫进行分子鉴定。根据 GenBank 数据库比对分析、NJ方法构建的系统进化树分析以及 BOLD 数据库查询分析,最终鉴定该样品为苹果异形小卷蛾。认为基于 DNA 条形码的分子鉴定能快速、准确地鉴定苹果异形小卷蛾。 相似文献
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Neil Boonham Rachel Glover Jenny Tomlinson Rick Mumford 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(3):355-363
The detection and identification of plant pathogens currently relies upon a very diverse range of techniques and skills, from
traditional culturing and taxonomic skills to modern molecular-based methods. The wide range of methods employed reflects
the great diversity of plant pathogens and the hosts they infect. The well-documented decline in taxonomic expertise, along
with the need to develop ever more rapid and sensitive diagnostic methods has provided an impetus to develop technologies
that are both generic and able to complement traditional skills and techniques. Real-time polymerase chain reaction (PCR)
is emerging as one such generic platform technology and one that is well suited to high-throughput detection of a limited
number of known target pathogens. Real-time PCR is now exploited as a front line diagnostic screening tool in human health,
animal health, homeland security, biosecurity as well as plant health. Progress with developing generic techniques for plant
pathogen identification, particularly of unknown samples, has been less rapid. Diagnostic microarrays and direct nucleic acid
sequencing (de novo sequencing) both have potential as generic methods for the identification of unknown plant pathogens but
are unlikely to be suitable as high-throughput detection techniques. This paper will review the application of generic technologies
in the routine laboratory as well as highlighting some new techniques and the trend towards multi-disciplinary studies. 相似文献
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L. Chalupowicz A. Dombrovsky V. Gaba N. Luria M. Reuven A. Beerman O. Lachman O. Dror G. Nissan S. Manulis-Sasson 《Plant pathology》2019,68(2):229-238
Reliable detection and identification of plant pathogens are essential for disease control strategies. Diagnostic methods commonly used to detect plant pathogens have limitations such as requirement of prior knowledge of the genome sequence, low sensitivity and a restricted ability to detect several pathogens simultaneously. The development of advanced DNA sequencing technologies has enabled determination of total nucleic acid content in biological samples. The possibility of using the single-molecule sequencing platform of Oxford Nanopore as a general method for diagnosis of plant diseases was examined. It was tested by sequencing DNA or RNA isolated from tissues with symptoms from plants of several families inoculated with known pathogens (e.g. bacteria, viruses, fungi, phytoplasma). Additionally, samples of groups of 200 seeds containing one infected seed of each of two or three pathogens, as well as samples with symptoms but unidentified pathogens were tested. Sequencing results were analysed with Nanopore data analysis tools. In all the inoculated plants, pathogens were identified in real time within 1–2 h of running the Nanopore sequencer and were classified to the species or genus level. DNA sequencing or direct RNA sequencing of samples with unidentified disease agents were validated by conventional diagnostic procedures (e.g. PCR, ELISA, Koch test), which supported the results obtained by Nanopore sequencing. The advantages of this technology include: long read lengths, fast run times, portability, low cost and the possibility of use in every laboratory. This study indicates that adoption of the Nanopore platform will be greatly advantageous for routine laboratory diagnosis. 相似文献
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为改进和优化航空喷雾作业质量检测技术,进一步提高检测准确性与效率,本文通过对比分析国内外雾滴采集与检测技术,提出了基于智能手机拍照方式获取雾滴沉积图像,并利用数字图像处理技术,测算雾滴体积直径的新方法。设计开发了基于智能手机的航空喷雾质量检测系统(J-02),该系统主要包括便携式检测仪、专业检测软件、数据管理平台三部分。最后,通过与雾滴沉积分析系统(IDAS PRO)和显微镜(Leica M80)等传统检测手段对比测试验证表明,基于智能手机的航空喷雾质量检测系统适用于航空喷雾质量现场检测,且检测结果准确可靠。 相似文献
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利用优异基因资源改良小麦抗旱性是应对干旱和保障粮食安全的重要途径。结合国内外小麦抗旱性研究的最新进展和本研究组的研究实践,概述了现行主要抗旱性鉴定方法的适用对象和评价指标,以及小麦抗旱种质创新、抗旱基因资源发掘与利用等方面的研究成果,同时提出未来小麦抗旱性研究的重点任务和发展方向,即建立基于高通量表型鉴定的抗旱性综合评价技术体系,建立基于高通量基因型鉴定的抗旱基因资源发掘平台,创建基于综合运用多学科技能的智慧育种策略,以期为加快小麦抗旱性遗传改良提供信息资源和理论参考。 相似文献
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为了让农户能够直观了解及掌握常见病虫害的防治信息,帮助农户通过智能手机在农田、果园和茶园等现场方便快捷地获取作物病虫害图文识别要点与科学防治方法,为农户提供在线植保技术服务,本研究采用RESTful Web 服务架构设计,运用HTML5移动Web开发技术,借助微信平台作为用户访问入口,开发了一款跨平台 (android/iOS) 的农药速查软件系统,实现了农药信息查询、病虫害图谱查询及后台数据管理等功能。通过建立农药与病虫害间的关联关系,实现了从农药名称和病虫害名称两个途径查询农药信息;所构建的数据库涵盖了蔬菜、果树、水稻、茶叶及烟草等共30种福建省常规种植作物上的重要病虫害农药防治技术。初步运用验证结果表明,该系统整体实用性和稳定性较好,适合在农村基层推广应用。基于微信平台的农药速查系统能够满足植保新技术普及和应用的需求,可为农户提供简单便捷、对症下药的在线植保科技服务,对提高用户安全施药和科学防控能力、推进农药的增效减量均具有重要意义。 相似文献
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M. T. Kuska A.-K. Mahlein 《European journal of plant pathology / European Foundation for Plant Pathology》2018,152(4):987-992
Protection of crops against plant diseases is crucial in crop production. Agricultural practice and scientific research is confronted with new challenges. Environmentally friendly and sustainable solutions are increasingly demanded. Therefore, the precise detection of primary infection sites and disease dynamics is fundamental to make a decision for a subsequent management practice. In this context, optical sensors can provide an accurate and objective detection of plant diseases. This has awoken the interest and expectation from the public, farmers, and companies for sophisticated optical sensors in agriculture, providing promising solutions. Nevertheless, the application of optical sensors in a practical context in the field is still challenging, and sophisticated data analysis methods have to be developed. In general, the entire system pipeline, consisting of the type of sensor, the platform carrying the sensor, and the decision making process by data analysis has to be tailored to the specific problem. Here, we briefly recount the possibilities and challenges using optical sensors in research and practice for plant disease protection. Optical sensor-based approaches are considered as a key element in plant phenotyping. This overview addresses mainly hyperspectral imaging as it determines several plant parameters that represent the basis for more specific sensors in the future. 相似文献
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Global warming is one of the most complicated challenges of our time causing considerable tension on our societies and on the environment. The impacts of global warming are felt unprecedentedly in a wide variety of ways from shifting weather patterns that threatens food production, to rising sea levels that deteriorates the risk of catastrophic flooding. Among all aspects related to global warming, there is a growing concern on water resource management. This field is targeted at preventing future water crisis threatening human beings. The very first stage in such management is to recognize the prospective climate parameters influencing the future water resource conditions. Numerous prediction models, methods and tools, in this case, have been developed and applied so far. In line with trend, the current study intends to compare three optimization algorithms on the platform of a multilayer perceptron (MLP) network to explore any meaningful connection between large-scale climate indices (LSCIs) and precipitation in the capital of Iran, a country which is located in an arid and semi-arid region and suffers from severe water scarcity caused by mismanagement over years and intensified by global warming. This situation has propelled a great deal of population to immigrate towards more developed cities within the country especially towards Tehran. Therefore, the current and future environmental conditions of this city especially its water supply conditions are of great importance. To tackle this complication an outlook for the future precipitation should be provided and appropriate forecasting trajectories compatible with this region's characteristics should be developed. To this end, the present study investigates three training methods namely backpropagation (BP), genetic algorithms (GAs), and particle swarm optimization (PSO) algorithms on a MLP platform. Two frameworks distinguished by their input compositions are denoted in this study: Concurrent Model Framework (CMF) and Integrated Model Framework (IMF). Through these two frameworks, 13 cases are generated: 12 cases within CMF, each of which contains all selected LSCIs in the same lead-times, and one case within IMF that is constituted from the combination of the most correlated LSCIs with Tehran precipitation in each lead-time. Following the evaluation of all model performances through related statistical tests, Taylor diagram is implemented to make comparison among the final selected models in all three optimization algorithms, the best of which is found to be MLP-PSO in IMF. 相似文献