7 research outputs found

    Genetic Analysis and Mapping of QTLs for Soybean Biological Nitrogen Fixation Traits Under Varied Field Conditions

    Get PDF
    Soybean is an important economic and green manure crop that is widely used in intercropping and rotation systems due to its high biological nitrogen fixation (BNF) capacity and the resulting reduction in N fertilization. However, the genetic mechanisms underlying soybean BNF are largely unknown. Here, two soybean parent genotypes contrasting in BNF traits and 168 F9:11 recombinant inbred lines (RILs) were evaluated under four conditions in the field. The parent FC1 always produced more big nodules, yet fewer nodules in total than the parent FC2 in the field. Furthermore, nodulation in FC1 was more responsive to environmental changes than that in FC2. Broad-sense heritability (h2b) for all BNF traits varied from 0.48 to 0.87, which suggests that variation in the observed BNF traits was primarily determined by genotype. Moreover, two new QTLs for BNF traits, qBNF-16 and qBNF-17, were identified in this study. The qBNF-16 locus was detected under all of the four tested conditions, where it explained 15.9–59.0% of phenotypic variation with LOD values of 6.31–32.5. Meanwhile qBNF-17 explained 12.6–18.6% of observed variation with LOD values of 4.93–7.51. Genotype group analysis indicated that the FC1 genotype of qBNF-16 primarily affected nodule size (NS), while the FC2 genotype of qBNF-16 promoted nodule number (NN). On the other hand, the FC1 genotype of qBNF-17 influenced NN and the FC2 genotype of qBNF-17 impacted NS. The results on the whole suggest that these two QTLs might be valuable markers for breeding elite soybean varieties with high BNF capacities

    Knowledge discovery in data streams

    Full text link
    Knowing what to do with the massive amount of data collected has always been an ongoing issue for many organizations. While data mining has been touted to be the solution, it has failed to deliver the impact despite its successes in many areas. One reason is that data mining algorithms were not designed for the real world, i.e., they usually assume a static view of the data and a stable execution environment where resources are abundant. The reality however is that data are constantly changing and the execution environment is dynamic. Hence, it becomes difficult for data mining to truly deliver timely and relevant results. Recently, the processing of stream data has received many attention. What is interesting is that the methodology to design stream-based algorithms may well be the solution to the above problem. In this entry, we discuss this issue and present an overview of recent works

    A knowledge engineering approach to the recognition of genomic coding regions

    Get PDF
    āđ„āļ”āđ‰āļ—āļļāļ™āļ­āļļāļ”āļŦāļ™āļļāļ™āļāļēāļĢāļ§āļīāļˆāļąāļĒāļˆāļēāļāļĄāļŦāļēāļ§āļīāļ—āļĒāļēāļĨāļąāļĒāđ€āļ—āļ„āđ‚āļ™āđ‚āļĨāļĒāļĩāļŠāļļāļĢāļ™āļēāļĢāļĩ āļ›āļĩāļ‡āļšāļ›āļĢāļ°āļĄāļēāļ“ āļž.āļĻ.2556-255

    Discovering Interesting Patterns and Associations in Data Streams

    Get PDF
    A data stream is a sequence of items that arrive in a timely order. Different from data in traditional static databases, data streams are continuous, unbounded, usually come with high speed, and have a data value distribution that often changes with time (Guha, 2001). As more applications such as web transactions, telephone records, and network flows generate a large number of data streams every day, efficient knowledge discovery of data streams is an active and growing research area in data mining with broad applications. Traditional data mining algorithms are developed to work on a complete static dataset and, thus, cannot be applied directly in data stream applications.One area of data mining research is to mine association relationship in a data set. Most of association mining techniques for data streams can be categorized into two types: those developed based on frequent patterns and those developed based on closed patterns. Due to the number of frequent patterns are often huge and redundant, non-informative patterns are contained in frequent patterns. An alternative way is to develop the association mining approaches for data streaming applications based on closed patterns, which generally represent a small subset of all frequent patterns, but provide complete and condensed information. In these researches, the closed pattern mining is the prerequisite condition for non-redundant and informative association mining.In this dissertation, a sliding window technique for dynamic mining of closed patterns in data streams is proposed, and an approach of mining non-redundant and informative associations based on the discovered closed patterns is developed. The closed pattern and relevant association mining techniques are selected research area in this dissertation. First, the closed patterns for a given collection of data are currently the most compact data knowledge that can provide complete support information for all data patterns.Compared with other techniques, the proposed closed pattern mining technique has potential to largely decrease the number of subsequent combinatorial calculations performed on the data patterns. Second, the memory requirement to store the closed patterns and relevant associations is generally lower than the corresponding frequent patterns and associations. In some data streaming applications, memory usage is an important measurement, because in these applications memory usage is the bottleneck for knowledge discovery. Third, the associations generated for data streams are the knowledge used to identify the relations within the data. The discovered relations can find their wide applications in many data streaming environments.Different from the closed pattern mining techniques on traditional databases, which require multiple scans of the entire database, the proposed technique determines the closed patterns with a single scan. It is an incremental mining process; as the sliding window advances, new data transactions enter and old data transactions exit the window. But instead of regenerating closed patterns from the entire window, the proposed technique updates the old set of closed patterns whenever a new transaction arrives and/or an old transaction leaves the sliding window to obtain the current set of closed patterns. This incremental feature allows the user to get the most recent updated closed patterns without rescanning the entire updated database, which saves not only the computation time, but more importantly, the I/O operating time to load and write data from database to memory. Third, the proposed sliding window technique can handle both the insertion and deletion operations independently, which allows the user to adjust the sliding window size in different application environments. Furthermore, the proposed interesting patterns and association mining framework can handle different users' requests at the same time at their specified support and confidence thresholds, and interested input and output patterns.The research includes both theoretical proofs of correctness for the proposed algorithms and simulation experiments to compare the proposed techniques with those existing in the literature using synthetic and real datasets. The utility of the proposed technique is applied to sensor network databases of a traffic management and an environmental monitoring site for missing data estimation purpose

    Multikonferenz Wirtschaftsinformatik (MKWI) 2016: Technische UniversitÃĪt Ilmenau, 09. - 11. MÃĪrz 2016; Band III

    Get PDF
    Übersicht der Teilkonferenzen Band III â€Ē Service Systems Engineering â€Ē Sicherheit, Compliance und VerfÞgbarkeit von GeschÃĪftsprozessen â€Ē Smart Services: Kundeninduzierte Kombination komplexer Dienstleistungen â€Ē Strategisches IT-Management â€Ē Student Track â€Ē Telekommunikations- und Internetwirtschaft â€Ē Unternehmenssoftware – quo vadis? â€Ē Von der Digitalen Fabrik zu Industrie 4.0 – Methoden und Werkzeuge fÞr die Planung und Steuerung von intelligenten Produktions- und Logistiksystemen â€Ē Wissensmanagemen
    corecore