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1.
Sensors (Basel) ; 23(17)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37688097

RESUMO

Currently, strawberry harvesting relies heavily on human labour and subjective assessments of ripeness, resulting in inconsistent post-harvest quality. Therefore, the aim of this work is to automate this process and provide a more accurate and efficient way of assessing ripeness. We explored a unique combination of YOLOv7 object detection and augmented reality technology to detect and visualise the ripeness of strawberries. Our results showed that the proposed YOLOv7 object detection model, which employed transfer learning, fine-tuning and multi-scale training, accurately identified the level of ripeness of each strawberry with an mAP of 0.89 and an F1 score of 0.92. The tiny models have an average detection time of 18 ms per frame at a resolution of 1280 × 720 using a high-performance computer, thereby enabling real-time detection in the field. Our findings distinctly establish the superior performance of YOLOv7 when compared to other cutting-edge methodologies. We also suggest using Microsoft HoloLens 2 to overlay predicted ripeness labels onto each strawberry in the real world, providing a visual representation of the ripeness level. Despite some challenges, this work highlights the potential of augmented reality to assist farmers in harvesting support, which could have significant implications for current agricultural practices.


Assuntos
Realidade Aumentada , Aprendizado Profundo , Fragaria , Trabalho de Parto , Humanos , Gravidez , Feminino , Agricultura
2.
Sensors (Basel) ; 22(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36366030

RESUMO

Recent years have witnessed an increasing interest in deploying state-of-the-art augmented reality (AR) head-mounted displays (HMDs) for agri-food applications. The benefits of AR HMDs to agri-food industry stakeholders (e.g., food suppliers, retail/food service) have received growing attention and recognition. AR HMDs enable users to make healthier dietary choices, experience novel changes in their perception of taste, enhance the cooking and food shopping experience, improve productivity at work and enhance the implementation of precision farming. Therefore, although development costs are still high, the case for integration of AR in food chains appears to be compelling. This review will present the most recent developments of AR HMDs for agri-food relevant applications. The summarized applications can be clustered into different themes: (1) dietary and food nutrition assessment; (2) food sensory science; (3) changing the eating environment; (4) retail food chain applications; (5) enhancing the cooking experience; (6) food-related training and learning; and (7) food production and precision farming. Limitations of current practices will be highlighted, along with some proposed applications.


Assuntos
Realidade Aumentada , Óculos Inteligentes , Atenção , Aprendizagem
3.
Psychol Res ; 82(2): 407-428, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27783147

RESUMO

Previous studies have reported an age-related decline in spatial abilities. However, little is known about whether the presence of other, task-irrelevant stimuli during learning further affects spatial cognition in older adults. Here we embedded virtual environments with moving crowds of virtual human pedestrians (Experiment 1) or objects (Experiment 2) whilst participants learned a route and landmarks embedded along that route. In subsequent test trials we presented clips from the learned route and measured spatial memory using three different tasks: a route direction task (i.e. whether the video clip shown was a repetition or retracing of the learned route); an intersection direction task; and a task involving identity of the next landmark encountered. In both experiments, spatial memory was tested in two separate sessions: first following learning of an empty maze environment and second using a different maze which was populated. Older adults performed worse than younger adults in all tasks. Moreover, the presence of crowds during learning resulted in a cost in performance to the spatial tasks relative to the 'no crowds' condition in older adults but not in younger adults. In contrast, crowd distractors did not affect performance on the landmark sequence task. There was no age-related cost on performance with object distractors. These results suggest that crowds of human pedestrians selectively capture older adults' attention during learning. These findings offer further insights into how spatial memory is affected by the ageing process, particularly in scenarios which are representative of real-world situations.


Assuntos
Cognição/fisiologia , Aglomeração/psicologia , Percepção Espacial , Memória Espacial/fisiologia , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resolução de Problemas , Navegação Espacial , Adulto Jovem
4.
Psychol Res ; 81(4): 764-776, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27150637

RESUMO

Affect, space, and multisensory integration are processes that are closely linked. However, it is unclear whether the spatial location of emotional stimuli interacts with multisensory presentation to influence the emotional experience they induce in the perceiver. In this study, we used the unique advantages of virtual reality techniques to present potentially aversive crowd stimuli embedded in a natural context and to control their display in terms of sensory and spatial presentation. Individuals high in crowdphobic fear navigated in an auditory-visual virtual environment, in which they encountered virtual crowds presented through the visual channel, the auditory channel, or both. They reported the intensity of their negative emotional experience at a far distance and at a close distance from the crowd stimuli. Whereas auditory-visual presentation of close feared stimuli amplified negative feelings, auditory-visual presentation of distant feared stimuli did not amplify negative feelings. This suggests that spatial closeness allows multisensory processes to modulate the intensity of the emotional experience induced by aversive stimuli. Nevertheless, the specific role of auditory stimulation must be investigated to better understand this interaction between multisensory, affective, and spatial representation processes. This phenomenon may serve the implementation of defensive behaviors in response to aversive stimuli that are in position to threaten an individual's feeling of security.


Assuntos
Estimulação Acústica/psicologia , Percepção Auditiva/fisiologia , Medo/fisiologia , Medo/psicologia , Estimulação Luminosa , Percepção Visual/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Exp Brain Res ; 234(6): 1555-74, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26821318

RESUMO

Recent evidence suggests that familiarity with an environment may protect against spatial memory decline for familiar objects in older adults. We investigated whether a familiar context also reduces age-related decline in spatial memory for novel objects. Twenty-four younger and 23 older participants viewed a virtual rendering of a local environment along two different routes, each through a well-known (West) or lesser-known (East) area within the environment. Older and younger participants reported being more familiar with one (i.e. West) area than the other. In each trial, participants were presented with one route and were instructed to learn ten novel objects and their locations along the route. Following learning, participants immediately completed five test blocks: an object recognition task, an egocentric spatial processing (direction judgement) task, an allocentric spatial processing (proximity judgement) task and two pen-and-paper tests to measure cognitive mapping abilities. First we found an age effect with worse performance by older than younger adults in all spatial tasks, particularly in allocentric spatial processing. However, our results suggested better memory for objects and directions, but not proximity judgements, when the task was associated with more familiar than unfamiliar contexts, in both age groups. There was no benefit of context when a separate young adult group (N = 24) was tested, who reported being equally familiar with both areas. These results suggest an important facilitatory role of context familiarity on object recognition, and in particular egocentric spatial memory, and have implications for enhancing spatial memory in older adults.


Assuntos
Envelhecimento/fisiologia , Reconhecimento Psicológico/fisiologia , Aprendizagem Espacial/fisiologia , Memória Espacial/fisiologia , Navegação Espacial/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Front Aging Neurosci ; 14: 806418, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356302

RESUMO

Spatial cognition is known to decline with aging. However, little is known about whether training can reduce or eliminate age-related deficits in spatial memory. We investigated whether a custom-designed video game involving spatial navigation, obstacle avoidance, and balance control would improve spatial memory in older adults. Specifically, 56 healthy adults aged 65 to 84 years received 10 sessions of multicomponent video game training, based on a virtual cityscape, over 5 weeks. Participants were allocated to one of three training conditions: the main intervention, the "CityQuest" group (n = 19), and two control groups, spatial navigation without obstacle avoidance ("Spatial Navigation-only" group, n = 21) and obstacle avoidance without spatial navigation ("Obstacles-only" group, n = 15). Performance on object recognition, egocentric and allocentric spatial memory (incorporating direction judgment tasks and landmark location tasks, respectively), navigation strategy preference, and executive functioning was assessed in pre- and post-intervention sessions. The results showed an overall benefit on performance in a number of spatial memory measures and executive function for participants who received spatial navigation training, particularly the CityQuest group, who also showed significant improvement on the landmark location task. However, there was no evidence of a shift from egocentric to allocentric strategy preference. We conclude that spatial memory in healthy older participants is amenable to improvement with training over a short term. Moreover, technology based on age-appropriate, multicomponent video games may play a key role in cognitive training in older adults.

7.
Exp Brain Res ; 204(3): 361-72, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19830410

RESUMO

Although the perception of emotion in individuals is an important social skill, very little is known about how emotion is determined from a crowd of individuals. We investigated the perception of emotion in scenes of crowds populated by dynamic characters each expressing an emotion. Facial expressions were masked in these characters and emotion was conveyed using body motion and posture only. We systematically varied the proportion of characters in each scene depicting one of two emotions and participants were required to categorise the overall emotion of the crowd. In Experiment 1, we found that the perception of emotions in a crowd is efficient even with relatively brief exposures of the crowd stimuli. Furthermore, the emotion of a crowd was generally determined by the relative proportions of characters conveying it, although we also found that some emotions dominated perception. In Experiment 2, we found that an increase in crowd size was not associated with a relative decrease in the efficiency with which the emotion was categorised. Our findings suggest that body motion is an important social cue in perceiving the emotion of crowds and have implications for our understanding of how we perceive social information from groups.


Assuntos
Emoções , Postura , Percepção Social , Percepção Visual , Adolescente , Adulto , Idoso , Análise de Variância , Criança , Sinais (Psicologia) , Feminino , Humanos , Julgamento , Masculino , Pessoa de Meia-Idade , Percepção de Movimento , Estimulação Luminosa , Testes Psicológicos , Tempo de Reação , Adulto Jovem
8.
J Mot Behav ; 51(3): 245-258, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29741471

RESUMO

The use of both hands simultaneously when manipulating objects is fairly commonplace, but it is not known what factors encourage people to use two hands as opposed to one during simple tasks such as transport. In particular, we are interested in three possible transport strategies: unimanual transport, handing off between hands, and symmetric bimanual transport. In this study, we investigate the effect of object size, weight, and starting and ending position (configuration) as well as the need to balance the object on the use of these three strategies in a bowl-moving task. We find that configuration and balance have a strong effect on choice of strategy, and size and weight have a weaker effect. Hand-offs are most often used when the task requires moving an object from left to right and vice versa, while the unimanual strategy was frequently used when passing front to back. The bimanual strategy is only weakly affected by configuration. The need to balance an object causes subjects to favor unimanual and bimanual strategies over the hand-off. In addition, an analysis of transport duration and body rotation suggests that strategy choice may be driven by the desire to minimize body rotation.


Assuntos
Lateralidade Funcional/fisiologia , Mãos/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Feminino , Força da Mão/fisiologia , Humanos , Masculino , Rotação , Adulto Jovem
9.
J Mech Behav Biomed Mater ; 77: 116-124, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28898722

RESUMO

Premixed calcium phosphate cements (CPC's) are becoming the material of choice for injectable cements as a result of their effective delivery to the target implantation site. For orthopaedic use, it is of vital importance that the attributes of these CPC's are not compromised by irradiation sterilization. Therefore, the aim of this study is to determine the influence of irradiation sterilization on a range of premixed CPC's, with an emphasis on improving product shelf life through the use of optimal packaging configurations and annealing steps. Electron spin resonance (ESR) confirmed the presence of free radicals in the inorganic phase of the CPC paste following irradiation. The inclusion of a 24-h annealing step was the only successful method in reducing the degree of free radical formation. Based on the results of injectability force testing, it was revealed that an annealing step greater than 24-h significantly altered the viscosity, however; at 24-h the key attributes of the CPC paste were minimally effected. Overall, it was established that vacuum packing the CPC paste, placing the contents into a foil pouch, gamma irradiating at the minimal dose required and using an annealing step of ≤ 24-h, has the potential to extend the shelf life of the cement.


Assuntos
Materiais Biocompatíveis/química , Cimentos Ósseos/química , Fosfatos de Cálcio/administração & dosagem , Fosfatos de Cálcio/química , Cromatografia em Gel , Colorimetria , Força Compressiva , Durapatita/química , Espectroscopia de Ressonância de Spin Eletrônica , Elétrons , Radicais Livres , Raios gama , Campos Magnéticos , Teste de Materiais , Oxigênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Viscosidade , Difração de Raios X
10.
IEEE Trans Vis Comput Graph ; 23(5): 1454-1464, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28026776

RESUMO

We propose a new semantic-level crowd evaluation metric in this paper. Crowd simulation has been an active and important area for several decades. However, only recently has there been an increased focus on evaluating the fidelity of the results with respect to real-world situations. The focus to date has been on analyzing the properties of low-level features such as pedestrian trajectories, or global features such as crowd densities. We propose the first approach based on finding semantic information represented by latent Path Patterns in both real and simulated data in order to analyze and compare them. Unsupervised clustering by non-parametric Bayesian inference is used to learn the patterns, which themselves provide a rich visualization of the crowd behavior. To this end, we present a new Stochastic Variational Dual Hierarchical Dirichlet Process ( SV-DHDP) model. The fidelity of the patterns is computed with respect to a reference, thus allowing the outputs of different algorithms to be compared with each other and/or with real data accordingly. Detailed evaluations and comparisons with existing metrics show that our method is a good alternative for comparing crowd data at a different level and also works with more types of data, holds fewer assumptions and is more robust to noise.

11.
Injury ; 44(12): 1871-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24074829

RESUMO

Current evidences show that recombinant human bone morphogenetic protein 7 (rhBMP-7, eptotermin alfa) can be considered an effective alternative to autologous bone graft (ABG) in the treatment of tibial nonunions. Few studies, so far, have analysed the costs of treating tibial nonunions with either rhBMP-7 or ABG and none of them has specifically considered the Italian situation. The aim of the present study was to capture, through observational retrospective methods, the direct medical costs associated with the treatment of tibial nonunions with rhBMP-7 or ABG in Italy and to compare the cost effectiveness of the two interventions. The secondary objective was to perform a cost-reimbursement analysis for hospitalisations associated with the two treatments. Data of 54 patients with indication for tibial nonunion were collected from existing data sources. Of these patients, 26 were treated with ABG and 28 with rhBMP-7. The study captured the direct medical costs for treating each tibial nonunion, considering both inpatient and outpatient care. The hospital reimbursement was calculated from discharge registries, based on diagnosis-related group (DRG) values. A subgroup of patients (n=30) was also interviewed to capture perceived health during the follow-up, and the quality-adjusted life years (QALYs) were subsequently computed. The two groups were similar for what concerns baseline characteristics. While the medical costs incurred during the hospitalisation associated with treatment were on average €3091.21 higher (P<0.001) in patients treated with rhBMP-7 (reflecting the product procurement costs), the costs incurred during the follow-up were on average €2344.45 higher (P=0.02) in patients treated with ABG. Considering all costs incurred from the treatment, there was a borderline statistical evidence (P=0.04) for a mean increase of €795.42, in the rhBMP-7 group. Furthermore, the study demonstrated that, without appropriate reimbursement, the hospital undergoes significant losses (P=0.003) when using rhBMP-7 instead of ABG. In contrast to these losses, in Italy, the average cost to achieve a successful outcome was €488.96 lower in patients treated with rhBMP-7 and, additionally, the cost per QALY gained was below the cost-utility threshold of $50,000.


Assuntos
Proteína Morfogenética Óssea 2/economia , Proteína Morfogenética Óssea 2/uso terapêutico , Transplante Ósseo/economia , Fixação Intramedular de Fraturas , Fraturas não Consolidadas/economia , Tempo de Internação/economia , Fraturas da Tíbia/economia , Protocolos Clínicos , Análise Custo-Benefício , Feminino , Seguimentos , Fixação Intramedular de Fraturas/economia , Fixação Intramedular de Fraturas/métodos , Consolidação da Fratura , Fraturas não Consolidadas/epidemiologia , Fraturas não Consolidadas/terapia , Custos de Cuidados de Saúde , Humanos , Itália/epidemiologia , Masculino , Readmissão do Paciente/economia , Anos de Vida Ajustados por Qualidade de Vida , Proteínas Recombinantes/economia , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Fraturas da Tíbia/epidemiologia , Fraturas da Tíbia/terapia , Resultado do Tratamento
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