Search Results (2)

Understanding the progression of host–pathogen interaction through time by hyperspectral features is vital for tracking yellow rust (Puccinia striiformis) development, one of the major diseases of wheat. However, well-designed features are still open issues that impact the performance of relevant models to nondestructively detect pathological progress of wheat rust. The aim of this paper is (1) to propose a novel wavelet-based rust spectral feature set (WRSFs) to uncover wheat rust-related processes; and (2) to evaluate the performance and robustness of the proposed WRSFs and models for retrieving the progression of host–pathogen interaction and tracking rust development. A hyperspectral dataset was collected by analytical spectral devices (ASD) spectroradiometer and Headwall spectrograph, along with corresponding physiological measurements of chlorophyll index (CHL), nitrogen balance index (NBI), anthocyanin index (ANTH), and percentile dry matter (PDM) from the 7th to 41st day after inoculation (dai) under controlled conditions. The resultant findings suggest that the progression of yellow rust on wheat is better characterized by the proposed WRSFs (R² > 0.7). The WRSFs-based PLSR model provides insight into specific leaf biophysical variations in the rust pathological progress. To evaluate the efficiency of the proposed WRSFs on yellow rust discrimination during different infestation stages, the identified WRSFs and vegetation indices (VIs) were fed into linear discriminant analysis (LDA) and support vector machine (SVM) classification frames. The WRSFs in conjunction with a SVM classifier can obtain better performance than that of LDA method and the VIs-based models. Overall, synthesizing the biophysical analysis, retrieving accuracy, and classification performance, we recommend the proposed WRSFs for monitoring the progression of the host–pathogen interaction of yellow rust on wheat cross various hyperspectral sensors. Full article

This paper proposes the Grid technology as an integration method of information, existing procedures and resources in the Public Administration. The exposed work supposes, from the point of view of the electronic government, an advance of future trends by means of the usage of Grid technology. On the other hand, from the perspective of Grid technology, the electronic government opens a non-evident field of application for this emergent paradigm of distributed computing. This paper explains gCitizen, which is a Grid middleware based on the GT4 components and WSRF implementation (which are the state-of-the-art in middleware for Grid computing), incorporating new protocols and services which cover the requirements for the integration purposes in the eGovernment frameworks. The system architecture has been designed to enable using the services deployed without a specific a priori knowledge of them. The gCitizen middleware also defines a data model to provide interoperability in the exchange of the information among the different gCitizen services. Full article