1,304 research outputs found

    Fast object detection in pastoral landscapes using a multiple expert colour feature extreme learning machine

    Get PDF
    Fast and accurate object detection is a desire of many vision-guided robotics based systems. Agriculture is an area where detection accuracy is often sacrificed for speed, especially in the pursuit of real time results. Pastoral landscapes are especially challenging with varying levels of complexity, as competing objects are rarely textually smooth or visibly different from surroundings. This study presents a machine learning algorithm designed for object detection called the Multiple Expert Colour Extreme Learning Machine (MEC-ELM). The MEC-ELM is a multiple expert implementation of a Colour Feature Extreme Learning Machine (CF-ELM). The CF-ELM is itself a modification of the Extreme Learning Machine (ELM) with a partially connected hidden layer and a fully connected output layer, taking 3 inputs. The inputs can be utilised by multiple colour systems, including, RGB, Y'UV and HSV. Colour inputs were chosen, as colour is not sensitive to adjustments in scale, size and location and provides information not available in the standard grey-scale ELM. In the MEC-ELM algorithm, feature extraction and classification techniques were implemented simultaneously making a fully functional object detection algorithm. The algorithm was tested on weed detection and cattle detection from a video feed, delivering 0.89 (cattle) to 0.98 (weeds) accuracy in tuning and a precision of 0.61 to 0.95 in testing, with classification times between 0.5s to 1s per frame. The algorithm has been designed with complex and unpredictable terrain in mind, making it an ideal application for agricultural or pastoral landscapes

    Detection of Parthenium Weed (Parthenium hysterophorus L.) and Its Growth Stages Using Artificial Intelligence

    Get PDF
    Parthenium weed (Parthenium hysterophorus L. (Asteraceae)), native to the Americas, is in the top 100 most invasive plant species in the world. In Australia, it is an annual weed (herb/shrub) of national significance, especially in the state of Queensland where it has infested both agricultural and conservation lands, including riparian corridors. Effective control strategies for this weed (pasture management, biological control, and herbicide usage) require populations to be detected and mapped. However, the mapping is made difficult due to varying nature of the infested landscapes (e.g., uneven terrain). This paper proposes a novel method to detect and map parthenium populations in simulated pastoral environments using Red-Green-Blue (RGB) and/or hyperspectral imagery aided by artificial intelligence. Two datasets were collected in a control environment using a series of parthenium and naturally co-occurring, non-parthenium (monocot) plants. RGB images were processed with a YOLOv4 Convolutional Neural Network (CNN) implementation, achieving an overall accuracy of 95% for detection, and 86% for classification of flowering and non-flowering stages of the weed. An XGBoost classifier was used for the pixel classification of the hyperspectral dataset—achieving a classification accuracy of 99% for each parthenium weed growth stage class; all materials received a discernible colour mask. When parthenium and non-parthenium plants were artificially combined in various permutations, the pixel classification accuracy was 99% for each parthenium and non-parthenium class, again with all materials receiving an accurate and discernible colour mask. Performance metrics indicate that our proposed processing pipeline can be used in the preliminary design of parthenium weed detection strategies, and can be extended for automated processing of collected RGB and hyperspectral airborne unmanned aerial vehicle (UAV) data. The findings also demonstrate the potential for images collected in a controlled, glasshouse environment to be used in the preliminary design of invasive weed detection strategies in the field

    The Segmented Colour Feature Extreme Learning Machine: Applications in Agricultural Robotics

    Get PDF
    This study presents the Segmented Colour Feature Extreme Learning Machine (SCF-ELM). The SCF-ELM is inspired by the Extreme Learning Machine (ELM) which is known for its rapid training and inference times. The ELM is therefore an ideal candidate for an ensemble learning algorithm. The Colour Feature Extreme Learning Machine (CF-ELM) is used in this study due to its additional ability to extract colour image features. The SCF-ELM is an ensemble learner that utilizes feature mapping via k-means clustering, a decision matrix and majority voting. It has been evaluated on a range of challenging agricultural object classification scenarios including weed, livestock and machinery detection. SCF-ELM model performance results were excellent both in terms of detection, 90 to 99% accuracy, and also inference times, around 0.01(s) per image. The SCF-ELM was able to compete or improve upon established algorithms in its class, indicating its potential for remote computing applications in agriculture

    Automated detection of archaeological mounds using machine-learning classification of multisensor and multitemporal satellite data.

    Get PDF
    This paper presents an innovative multisensor, multitemporal machine-learning approach using remote sensing big data for the detection of archaeological mounds in Cholistan (Pakistan). The Cholistan Desert presents one of the largest concentrations of Indus Civilization sites (from ca 3300 to 1500 BC). Cholistan has figured prominently in theories about changes in water availability, the rise and decline of the Indus Civilization, and the transformation of fertile monsoonal alluvial plains into an extremely arid margin. This paper implements a multisensor, multitemporal machine-learning approach for the remote detection of archaeological mounds. A classifier algorithm that employs a large-scale collection of synthetic-aperture radar and multispectral images has been implemented in Google Earth Engine, resulting in an accurate probability map for mound-like signatures across an area that covers ca 36,000 km2 The results show that the area presents many more archaeological mounds than previously recorded, extending south and east into the desert, which has major implications for understanding the archaeological significance of the region. The detection of small (30 ha) suggests that there were continuous shifts in settlement location. These shifts are likely to reflect responses to a dynamic and changing hydrological network and the influence of the progressive northward advance of the desert in a long-term process that culminated in the abandonment of much of the settled area during the Late Harappan period.ER

    Examining the Capability of Supervised Machine Learning Classifiers in Extracting Flooded Areas from Landsat TM Imagery: A Case Study from a Mediterranean Flood

    Get PDF
    This study explored the capability of Support Vector Machines (SVMs) and regularised kernel Fisher’s discriminant analysis (rkFDA) machine learning supervised classifiers in extracting flooded area from optical Landsat TM imagery. The ability of both techniques was evaluated using a case study of a riverine flood event in 2010 in a heterogeneous Mediterranean region, for which TM imagery acquired shortly after the flood event was available. For the two classifiers, both linear and non-linear (kernel) versions were utilised in their implementation. The ability of the different classifiers to map the flooded area extent was assessed on the basis of classification accuracy assessment metrics. Results showed that rkFDA outperformed SVMs in terms of accurate flooded pixels detection, also producing fewer missed detections of the flooded area. Yet, SVMs showed less false flooded area detections. Overall, the non-linear rkFDA classification method was the more accurate of the two techniques (OA = 96.23%, K = 0.877). Both methods outperformed the standard Normalized Difference Water Index (NDWI) thresholding (OA = 94.63, K = 0.818) by roughly 0.06 K points. Although overall accuracy results for the rkFDA and SVMs classifications only showed a somewhat minor improvement on the overall accuracy exhibited by the NDWI thresholding, notably both classifiers considerably outperformed the thresholding algorithm in other specific accuracy measures (e.g. producer accuracy for the “not flooded” class was ~10.5% less accurate for the NDWI thresholding algorithm in comparison to the classifiers, and average per-class accuracy was ~5% less accurate than the machine learning models). This study provides evidence of the successful application of supervised machine learning for classifying flooded areas in Landsat imagery, where few studies so far exist in this direction. Considering that Landsat data is open access and has global coverage, the results of this study offers important information towards exploring the possibilities of the use of such data to map other significant flood events from space in an economically viable way

    Mapping Prosopis glandulosa (mesquite) invasion in the arid environment of South African using remote sensing techniques

    Get PDF
    A dissertation submitted to the School of Geography, Archaeology and Environmental Studies, Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science in Environmental Sciences. Johannesburg, March 2016.Mapping Prosopis glandulosa (mesquite) invasion in the arid environment of South Africa using remote sensing techniques Mureriwa, Nyasha Abstract Decades after the first introduction of the Prosopis spp. (mesquite) to South Africa in the late 1800s for its benefits, the invasive nature of the species became apparent as its spread in regions of South Africa resulting in devastating effects to biodiversity, ecosystems and the socio-economic wellbeing of affected regions. Various control and management practices that include biological, physical, chemical and integrated methods have been tested with minimal success as compared to the rapid spread of the species. From previous studies, it has been noted that one of the reasons for the low success rates in mesquite control and management is a lack of sufficient information on the species invasion dynamic in relation to its very similar co-existing species. In order to bridge this gap in knowledge, vegetation species mapping techniques that use remote sensing methods need to be tested for the monitoring, detection and mapping of the species spread. Unlike traditional field survey methods, remote sensing techniques are better at monitoring vegetation as they can cover very large areas and are time-effective and cost-effective. Thus, the aim of this research was to examine the possibility of mapping and spectrally discriminating Prosopis glandulosa from its native co-existing species in semi-arid parts of South Africa using remote sensing methods. The specific objectives of the study were to investigate the spectral separability between Prosopis glandulosa and its co-existing species using field spectral data as well as to upscale the results to different satellites resolutions. Two machine learning algorithms (Random Forest (RF) and Support Vector Machines (SVM)) were also tested in the mapping processes. The first chapter of the study evaluated the spectral discrimination of Prosopis glandulosa from three other species (Acacia karoo, Acacia mellifera and Ziziphus mucronata) in the study area using in-situ spectroscopy in conjunction with the newly developed guided regularized random forest (GRRF) algorithm in identifying key wavelengths for multiclass classification. The GRRF algorithm was used as a method of reducing the problem of high dimensionality associated with hyperspectral data. Results showed that there was an increase in the accuracy of discrimination between the four species when the full set of 1825 wavelengths was used in classification (79.19%) as compared to the classification used by the 11 key wavelengths identified by GRRF (88.59%). Results obtained from the second chapter showed that it is possible to spatially discriminate mesquite from its co-existing acacia species and other general land-cover types at a 2 m resolution with overall accuracies of 86.59% for RF classification and 85.98% for SVM classification. The last part of the study tested the use of the more cost effective SPOT-6 imagery and the RF and SVM algorithms in mapping Prosopis glandulosa invasion and its co-existing indigenous species. The 6 m resolution analysis obtained accuracies of 78.46% for RF and 77.62% for SVM. Overall it was concluded that spatial and spectral discrimination of Prosopis glandulosa from its native co-existing species in semi-arid South Africa was possible with high accuracies through the use of (i) two high resolution, new generation sensors namely, WorldView-2 and SPOT-6; (ii) two robust classification algorithms specifically, RF and SVM and (iii) the newly developed GRRF algorithm for variable selection and reducing the high dimensionality problem associated with hyperspectral data. Some recommendations for future studies include the replication of this study on a larger scale in different invaded areas across the country as well as testing the robustness of the RF and SVM classifiers by making use of other machine learning algorithms and classification methods in species discrimination. Keywords: Prosopis glandulosa, field spectroscopy, cost effectiveness, Guided Regularised Random Forest, Support Vector Machines, Worldview-2, Spot-

    Sistema de conteo forestal, agrícola y ganadero mediante procesamiento de imágenes

    Get PDF
    Los sistemas de conteo actuales en agricultura y ganadería de precisión son manuales, costosos y se realizan con base en muestreos estadísticos. Consecuentemente, una herramienta que permita precisar y optimizar el sistema de conteo a través del procesamiento de imágenes sería fundamental para evaluar la cantidad de plantas en estadios tempranos, la calidad de los cultivos en el tiempo o el conteo exacto de cabezas de ganado. El proyecto plantea el desarrollo de un prototipo de un sistema software para realizar el conteo de poblaciones de plantas y/o ganado mediante técnicas de visión artificial aplicadas sobre videos tomados desde un dron que sobrevuela el campo o desde cámara en tierra. Se generó un corpus de videos propios para cada aplicación cubriendo diversas alturas y perspectiva del dispositivo de captura, diferentes cultivos y variaciones en las condiciones ambientales. Los resultados fueron satisfactorios en todos los escenarios experimentados, haciendo posible validar el prototipo a fin de escalar a una versión comercial que incorpore robustez frente a variaciones en coloración de objetos, tipos de campo, condiciones ambientales, entre otras.Sociedad Argentina de Informática e Investigación Operativ

    Reconocimiento automático de ganado bovino a partir de imágenes aéreas tomadas con drones: Un enfoque exploratorio.

    Get PDF
    El sector ganadero en Colombia se ha visto afectado en los últimos años por el aumento del robo de ganado bovino generando pérdidas millonarias para el gremio. La ganadería en el país se realiza por pastoreo extensivo lo que hace difícil de monitorear los animales en tiempo real. En este trabajo se propuso una primera fase hacia la construcción de un sistema para la vigilancia automática de ganado a cielo abierto, mediante la adquisición de imágenes aéreas tomadas con drones. Para llevarlo a cabo, se tomaron alrededor de 13000 fotografías de ganado en cuatro fincas del oriente antioqueño, se etiquetaron manualmente y se construyó un modelo para la detección de ganado a partir de una arquitectura de redes neuronales profundas llamada YOLO. En las métricas de evaluación de desempeño del modelo entrenado, se obtuvieron valores de precisión del 82% con niveles de sensibilidad del 75% en etapas de prueba y validación. A pesar de que el estudio planteado es de tipo exploratorio, los resultados obtenidos muestran el potencial de utilizar este tipo de herramientas en la construcción de una aplicación funcional para la prevencióndel robo de ganado en Colombia
    corecore