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1.
Article in English | MEDLINE | ID: mdl-38889026

ABSTRACT

Previous research has demonstrated the potential of using pre-trained language models for decoding open vocabulary Electroencephalography (EEG) signals captured through a non-invasive Brain-Computer Interface (BCI). However, the impact of embedding EEG signals in the context of language models and the effect of subjectivity, remain unexplored, leading to uncertainty about the best approach to enhance decoding performance. Additionally, current evaluation metrics used to assess decoding effectiveness are predominantly syntactic and do not provide insights into the comprehensibility of the decoded output for human understanding. We present an end-to-end architecture for non-invasive brain recordings that brings modern representational learning approaches to neuroscience. Our proposal introduces the following innovations: 1) an end-to-end deep learning architecture for open vocabulary EEG decoding, incorporating a subject-dependent representation learning module for raw EEG encoding, a BART language model, and a GPT-4 sentence refinement module; 2) a more comprehensive sentence-level evaluation metric based on the BERTScore; 3) an ablation study that analyses the contributions of each module within our proposal, providing valuable insights for future research. We evaluate our approach on two publicly available datasets, ZuCo v1.0 and v2.0, comprising EEG recordings of 30 subjects engaged in natural reading tasks. Our model achieves a BLEU-1 score of 42.75%, a ROUGE-1-F of 33.28%, and a BERTScore-F of 53.86%, achieving an increment over the previous state-of-the-art by 1.40%, 2.59%, and 3.20%, respectively.

2.
Sensors (Basel) ; 23(18)2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37765932

ABSTRACT

In this paper, different machine learning methodologies have been evaluated for the estimation of the multiple soil characteristics of a continental-wide area corresponding to the European region, using multispectral Sentinel-3 satellite imagery and digital elevation model (DEM) derivatives. The results confirm the importance of multispectral imagery in the estimation of soil properties and specifically show that the use of DEM derivatives improves the quality of the estimates, in terms of R2, by about 19% on average. In particular, the estimation of soil texture increases by about 43%, and that of cation exchange capacity (CEC) by about 65%. The importance of each input source (multispectral and DEM) in predicting the soil properties using machine learning has been traced back. It has been found that, overall, the use of multispectral features is more important than the use of DEM derivatives with a ration, on average, of 60% versus 40%.

3.
Sensors (Basel) ; 23(18)2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37765950

ABSTRACT

Defect segmentation of apples is an important task in the agriculture industry for quality control and food safety. In this paper, we propose a deep learning approach for the automated segmentation of apple defects using convolutional neural networks (CNNs) based on a U-shaped architecture with skip-connections only within the noise reduction block. An ad-hoc data synthesis technique has been designed to increase the number of samples and at the same time to reduce neural network overfitting. We evaluate our model on a dataset of multi-spectral apple images with pixel-wise annotations for several types of defects. In this paper, we show that our proposal outperforms in terms of segmentation accuracy general-purpose deep learning architectures commonly used for segmentation tasks. From the application point of view, we improve the previous methods for apple defect segmentation. A measure of the computational cost shows that our proposal can be employed in real-time (about 100 frame-per-second on GPU) and in quasi-real-time (about 7/8 frame-per-second on CPU) visual-based apple inspection. To further improve the applicability of the method, we investigate the potential of using only RGB images instead of multi-spectral images as input images. The results prove that the accuracy in this case is almost comparable with the multi-spectral case.

4.
Sensors (Basel) ; 23(8)2023 Apr 07.
Article in English | MEDLINE | ID: mdl-37112129

ABSTRACT

Precision agriculture has emerged as a promising approach to improve crop productivity and reduce the environmental impact. However, effective decision making in precision agriculture relies on accurate and timely data acquisition, management, and analysis. The collection of multisource and heterogeneous data for soil characteristics estimation is a critical component of precision agriculture, as it provides insights into key factors, such as soil nutrient levels, moisture content, and texture. To address these challenges, this work proposes a software platform that facilitates the collection, visualization, management, and analysis of soil data. The platform is designed to handle data from various sources, including proximity, airborne, and spaceborne data, to enable precision agriculture. The proposed software allows for the integration of new data, including data that can be collected directly on-board the acquisition device, and it also allows for the incorporation of custom predictive systems for soil digital mapping. The usability experiments conducted on the proposed software platform demonstrate that it is easy to use and effective. Overall, this work highlights the importance of decision support systems in the field of precision agriculture and the potential benefits of using such systems for soil data management and analysis.

5.
IEEE Trans Image Process ; 31: 5009-5024, 2022.
Article in English | MEDLINE | ID: mdl-35867369

ABSTRACT

The aesthetic quality of an image is defined as the measure or appreciation of the beauty of an image. Aesthetics is inherently a subjective property but there are certain factors that influence it such as, the semantic content of the image, the attributes describing the artistic aspect, the photographic setup used for the shot, etc. In this paper we propose a method for the automatic prediction of the aesthetics of an image that is based on the analysis of the semantic content, the artistic style and the composition of the image. The proposed network includes: a pre-trained network for semantic features extraction (the Backbone); a Multi Layer Perceptron (MLP) network that relies on the Backbone features for the prediction of image attributes (the AttributeNet); a self-adaptive Hypernetwork that exploits the attributes prior encoded into the embedding generated by the AttributeNet to predict the parameters of the target network dedicated to aesthetic estimation (the AestheticNet). Given an image, the proposed multi-network is able to predict: style and composition attributes, and aesthetic score distribution. Results on three benchmark datasets demonstrate the effectiveness of the proposed method, while the ablation study gives a better understanding of the proposed network.

6.
Sensors (Basel) ; 21(22)2021 Nov 09.
Article in English | MEDLINE | ID: mdl-34833529

ABSTRACT

Smart mirrors are devices that can display any kind of information and can interact with the user using touch and voice commands. Different kinds of smart mirrors exist: general purpose, medical, fashion, and other task specific ones. General purpose smart mirrors are suitable for home environments but the exiting ones offer similar, limited functionalities. In this paper, we present a general-purpose smart mirror that integrates several functionalities, standard and advanced, to support users in their everyday life. Among the advanced functionalities are the capabilities of detecting a person's emotions, the short- and long-term monitoring and analysis of the emotions, a double authentication protocol to preserve the privacy, and the integration of Alexa Skills to extend the applications of the smart mirrors. We exploit a deep learning technique to develop most of the smart functionalities. The effectiveness of the device is demonstrated by the performances of the implemented functionalities, and the evaluation in terms of its usability with real users.


Subject(s)
Emotions , Voice , Humans , Privacy
7.
Sensors (Basel) ; 21(13)2021 Jun 24.
Article in English | MEDLINE | ID: mdl-34202554

ABSTRACT

LoRa is a long-range and low-power radio technology largely employed in Internet of Things (IoT) scenarios. It defines the lower physical layer while other protocols, such as LoRaWAN, define the upper layers of the network. A LoRaWAN network assumes a star topology where each of the nodes communicates with multiple gateways which, in turn, forward the collected data to a network server. The main LoRaWAN characteristic is the central role of the gateways; however, in some application scenarios, a much lighter protocol stack, relying only on node capabilities and without the presence of gateways, can be more suitable. In this paper, we present a preliminary study for realizing a LoRa-based mesh network, not relying on LoRaWAN, that implements a peer-to-peer communication between nodes, without the use of gateways, and extends node reachability through multi-hop communication. To validate our investigations, we present a hardware/software prototype based on low-power-consumption devices, and we preliminarily assess the proposed solution.


Subject(s)
Surgical Mesh , Wireless Technology , Communication , Prostheses and Implants
8.
Sensors (Basel) ; 21(3)2021 Feb 02.
Article in English | MEDLINE | ID: mdl-33540652

ABSTRACT

We propose an anomaly detection based image quality assessment method which exploits the correlations between feature maps from a pre-trained Convolutional Neural Network (CNN). The proposed method encodes the intra-layer correlation through the Gram matrix and then estimates the quality score combining the average of the correlation and the output from an anomaly detection method. The latter evaluates the degree of abnormality of an image by computing a correlation similarity with respect to a dictionary of pristine images. The effectiveness of the method is tested on different benchmarking datasets (LIVE-itW, KONIQ, and SPAQ).

9.
Sensors (Basel) ; 21(3)2021 Feb 02.
Article in English | MEDLINE | ID: mdl-33540828

ABSTRACT

In this paper we present T1K+, a very large, heterogeneous database of high-quality texture images acquired under variable conditions. T1K+ contains 1129 classes of textures ranging from natural subjects to food, textile samples, construction materials, etc. T1K+ allows the design of experiments especially aimed at understanding the specific issues related to texture classification and retrieval. To help the exploration of the database, all the 1129 classes are hierarchically organized in 5 thematic categories and 266 sub-categories. To complete our study, we present an evaluation of hand-crafted and learned visual descriptors in supervised texture classification tasks.

10.
J Sports Med Phys Fitness ; 59(9): 1544-1550, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30421876

ABSTRACT

BACKGROUND: CrossFit is a strength and conditioning training program, that begin very popular in the last ten years. One of the most concerned characteristics of model is the high intensity activity performed under fatigue conditions that was proposed as potential risk of injuries; current literature on this topic was not conclusive. The purpose of this research was to examine injury epidemiology and risk factors for injury in CrossFit. METHODS: This is a retrospective observational study carried out by an anonymous, self-administered questionnaire in a convenience sample of CrossFit athletes. RESULTS: The questionnaire was completed and returned by 454 subjects, of which 325 (71.6%) were male with an average age of 28.8±7.9. 39.9% reported skeletal or muscles injury after to start training CrossFit. Lifetime Prevalence is 0.23 events per year of training/person. The average number of muscles and skeletal injuries reported was of 1.96±1.36. A percentage of 16.7% reported tendinitis. Time of CrossFit training is a determinant of tendinitis (aOR=1.02; P=0.021). Attending the On-Ramp program seemed to protect against the occurrence of injuries. CONCLUSIONS: According our results the risk of injury in the CrossFit practice is acceptable and, as discussed in a recent published review, CrossFit is comparable to other exercise programs with similar injury rates and health outcomes.


Subject(s)
Athletic Injuries/epidemiology , High-Intensity Interval Training/adverse effects , Musculoskeletal System/injuries , Adult , Female , Humans , Italy , Male , Prevalence , Retrospective Studies , Risk Factors , Surveys and Questionnaires , Tendinopathy/epidemiology , Young Adult
11.
Sensors (Basel) ; 18(1)2018 Jan 12.
Article in English | MEDLINE | ID: mdl-29329268

ABSTRACT

Automatic detection and localization of anomalies in nanofibrous materials help to reduce the cost of the production process and the time of the post-production visual inspection process. Amongst all the monitoring methods, those exploiting Scanning Electron Microscope (SEM) imaging are the most effective. In this paper, we propose a region-based method for the detection and localization of anomalies in SEM images, based on Convolutional Neural Networks (CNNs) and self-similarity. The method evaluates the degree of abnormality of each subregion of an image under consideration by computing a CNN-based visual similarity with respect to a dictionary of anomaly-free subregions belonging to a training set. The proposed method outperforms the state of the art.

12.
IEEE J Biomed Health Inform ; 21(3): 588-598, 2017 05.
Article in English | MEDLINE | ID: mdl-28114043

ABSTRACT

We propose a new dataset for the evaluation of food recognition algorithms that can be used in dietary monitoring applications. Each image depicts a real canteen tray with dishes and foods arranged in different ways. Each tray contains multiple instances of food classes. The dataset contains 1027 canteen trays for a total of 3616 food instances belonging to 73 food classes. The food on the tray images has been manually segmented using carefully drawn polygonal boundaries. We have benchmarked the dataset by designing an automatic tray analysis pipeline that takes a tray image as input, finds the regions of interest, and predicts for each region the corresponding food class. We have experimented with three different classification strategies using also several visual descriptors. We achieve about 79% of food and tray recognition accuracy using convolutional-neural-networks-based features. The dataset, as well as the benchmark framework, are available to the research community.


Subject(s)
Databases, Factual , Food/classification , Image Processing, Computer-Assisted/methods , Pattern Recognition, Automated/methods , Algorithms , Humans , Neural Networks, Computer
13.
J Opt Soc Am A Opt Image Sci Vis ; 33(1): 17-30, 2016 Jan 01.
Article in English | MEDLINE | ID: mdl-26831581

ABSTRACT

The recognition of color texture under varying lighting conditions remains an open issue. Several features have been proposed for this purpose, ranging from traditional statistical descriptors to features extracted with neural networks. Still, it is not completely clear under what circumstances a feature performs better than others. In this paper, we report an extensive comparison of old and new texture features, with and without a color normalization step, with a particular focus on how these features are affected by small and large variations in the lighting conditions. The evaluation is performed on a new texture database, which includes 68 samples of raw food acquired under 46 conditions that present single and combined variations of light color, direction, and intensity. The database allows us to systematically investigate the robustness of texture descriptors across large variations of imaging conditions.

14.
IEEE Trans Image Process ; 24(11): 3266-81, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25966475

ABSTRACT

In this paper, we shall consider the problem of deploying attention to the subsets of the video streams for collating the most relevant data and information of interest related to a given task. We formalize this monitoring problem as a foraging problem. We propose a probabilistic framework to model observer's attentive behavior as the behavior of a forager. The forager, moment to moment, focuses its attention on the most informative stream/camera, detects interesting objects or activities, or switches to a more profitable stream. The approach proposed here is suitable to be exploited for multistream video summarization. Meanwhile, it can serve as a preliminary step for more sophisticated video surveillance, e.g., activity and behavior analysis. Experimental results achieved on the UCR Videoweb Activities Data Set, a publicly available data set, are presented to illustrate the utility of the proposed technique.

15.
J Opt Soc Am A Opt Image Sci Vis ; 31(7): 1453-61, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-25121431

ABSTRACT

This paper presents a texture descriptor for color texture classification specially designed to be robust against changes in the illumination conditions. The descriptor combines a histogram of local binary patterns (LBPs) with a novel feature measuring the distribution of local color contrast. The proposed descriptor is invariant with respect to rotations and translations of the image plane and with respect to several transformations in the color space. We evaluated the proposed descriptor on the Outex test suite, by measuring the classification accuracy in the case in which training and test images have been acquired under different illuminants. The results obtained show that our descriptor outperforms the original LBP approach and its color variants, even when these are computed after color normalization. Moreover, it also outperforms several other color texture descriptors in the state of the art.

16.
Vision Res ; 49(8): 810-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19268685

ABSTRACT

Understanding visuomotor coordination requires the study of tasks that engage mechanisms for the integration of visual and motor information; in this paper we choose a paradigmatic yet little studied example of such a task, namely realistic drawing. On the one hand, our data indicate that the motor task has little influence on which regions of the image are overall most likely to be fixated: salient features are fixated most often. Viceversa, the effect of motor constraints is revealed in the temporal aspect of the scanpaths: (1) subjects direct their gaze to an object mostly when they are acting upon (drawing) it; and (2) in support of graphically continuous hand movements, scanpaths resemble edge-following patterns along image contours. For a better understanding of such properties, a computational model is proposed in the form of a novel kind of Dynamic Bayesian Network, and simulation results are compared with human eye-hand data.


Subject(s)
Art , Eye Movements/physiology , Hand/physiology , Psychomotor Performance/physiology , Algorithms , Fixation, Ocular/physiology , Humans , Models, Psychological , Movement/physiology , Vision, Binocular/physiology
17.
Comput Biol Med ; 37(1): 83-96, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16352300

ABSTRACT

In this paper a new method for segmenting medical images is presented, the multiresolution diffused expectation-maximization (MDEM) algorithm. The algorithm operates within a multiscale framework, thus taking advantage of the fact that objects/regions to be segmented usually reside at different scales. At each scale segmentation is carried out via the expectation-maximization algorithm, coupled with anisotropic diffusion on classes, in order to account for the spatial dependencies among pixels. This new approach is validated via experiments on a variety of medical images and its performance is compared with more standard methods.


Subject(s)
Algorithms , Image Processing, Computer-Assisted , Computer Simulation , Glaucoma/pathology , Humans , Skin Diseases/pathology , Tomography, X-Ray Computed/statistics & numerical data
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