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1.
Sensors (Basel) ; 24(16)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39204830

RESUMEN

Railway transportation has been integrated into people's lives. According to the "Notice on the release of the General Technical Specification of High-speed Railway Power Supply Safety Testing (6C System) System" issued by the National Railway Administration of China in 2012, it is required to install pantograph and slide monitoring devices in high-speed railway stations, station throats and the inlet and exit lines of high-speed railway sections, and it is required to detect the damage of the slider with high precision. It can be seen that the good condition of the pantograph slider is very important for the normal operation of the railway system. As a part of providing power for high-speed rail and subway, the pantograph must be paid attention to in railway transportation to ensure its integrity. The wear of the pantograph is mainly due to the contact power supply between the slide block and the long wire during high-speed operation, which inevitably produces scratches, resulting in depressions on the upper surface of the pantograph slide block. During long-term use, because the depression is too deep, there is a risk of fracture. Therefore, it is necessary to monitor the slider regularly and replace the slider with serious wear. At present, most of the traditional methods use automation technology or simple computer vision technology for detection, which is inefficient. Therefore, this paper introduces computer vision and deep learning technology into pantograph slide wear detection. Specifically, this paper mainly studies the wear detection of the pantograph slider based on deep learning and the main purpose is to improve the detection accuracy and improve the effect of segmentation. From a methodological perspective, this paper employs a linear array camera to enhance the quality of the data sets. Additionally, it integrates an attention mechanism to improve segmentation performance. Furthermore, this study introduces a novel image stitching method to address issues related to incomplete images, thereby providing a comprehensive solution.

2.
Psychophysiology ; 60(12): e14438, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37724827

RESUMEN

Although alpha-band activity has long been a focus of psychophysiological research, its modulation by emotional value during picture perception has only recently been studied systematically. Here, we review these studies and report that the most consistent alpha oscillatory pattern indexing emotional processing is an enhanced desynchronization (ERD) over posterior sensors when viewing emotional compared with neutral pictures. This enhanced alpha ERD is not specific to unpleasant picture content, as previously proposed for other measures of affective response, but has also been observed for pleasant stimuli. Evidence suggests that this effect is not confined to the alpha band but that it also involves a desynchronization of the lower beta frequencies (8-20 Hz). The emotional modulation of alpha ERD occurs even after massive stimulus repetition and when emotional cues serve as task-irrelevant distractors, consistent with the hypothesis that evaluative processes are mandatory in emotional picture processing. A similar enhanced ERD has been observed for other significant cues (e.g., conditioned aversive stimuli, or in anticipation of a potential threat), suggesting that it reflects cortical excitability associated with the engagement of the motivational systems.


Asunto(s)
Emociones , Motivación , Humanos , Emociones/fisiología , Percepción , Estimulación Luminosa , Electroencefalografía
3.
Zhongguo Yi Liao Qi Xie Za Zhi ; 47(2): 124-128, 2023 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-37096462

RESUMEN

This study proposed a vessel segmentation method based on Gabor features. According to the eigenvector of Hessian matrix of each pixel in the image, the vessel direction of each point was obtained to set the direction angle of Gabor filter, and the Gabor features of different vessel width at each point were extracted to establish the 6D vectors of each point. By reducing the dimension of the 6D vector, the 2D vector of each point was obtained and fused with the original image G channel. U-Net neural network was used to classify the fused image to segment vessels. The experimental results of this method in DRIVE dataset showed that this method had a good effect on the detection of small vessels and vessels at the intersection.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Vasos Retinianos
4.
Behav Res Ther ; 158: 104181, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36087438

RESUMEN

Avoidance behavior is a core symptom of anxiety disorders that may hinder adaptation. Anxiety disorders are heterogeneous and previous research suggests to decompose anxiety into two dimensions: anxious apprehension and anxious arousal. How these two dimensions are associated with avoidance of and exposure to threatening stimuli, as well as their accompanying neural processes, is barely understood. We examined threat processing using event-related potentials (N1, LPP) from 134 individuals considering the influence of anxiety dimensions. During a two-phase picture-viewing task the participants watched neutral and threatening pictures, which they were instructed to either avoid or attend to during repeated presentations. Results showed that threatening compared to neutral pictures were associated with increased attention allocation (N1) and in-depth processing (LPP), modulated by task-instructions (lower during avoidance). Further, increased anxious apprehension was associated with heightened automatic attention (increased N1), followed by reduced LPP amplitudes for threatening pictures suggesting reduced in-depth processing. During re-exposure, threatening pictures were associated with increased in-depth processing, with no difference between previously avoided and maintained pictures. Together, these results illustrate that avoidance and high anxious apprehension seem to lead to similar neural changes in the processing of aversive images that may conflict with long-term adaptation.


Asunto(s)
Electroencefalografía , Potenciales Evocados , Ansiedad , Trastornos de Ansiedad , Atención , Electroencefalografía/métodos , Humanos
5.
Hum Brain Mapp ; 43(10): 3293-3305, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35384132

RESUMEN

Enhanced visual cortex activation by negative compared to neutral stimuli is often attributed to modulating feedback from the amygdala, but evidence from lesion studies is scarce, particularly regarding differential effects of left and right amygdala lesions. Therefore, we compared visual cortex activation by negative and neutral complex scenes in an event-related fMRI study between 40 patients with unilateral temporal lobe resection (TLR; 19 left [lTLR], 21 right [rTLR]), including the amygdala, and 20 healthy controls. We found preserved hemodynamic emotion modulation of visual cortex in rTLR patients and only subtle reductions in lTLR patients. In contrast, rTLR patients showed a significant decrease in visual cortex activation irrespective of picture content. In line with this, healthy controls showed small emotional modulation of the left amygdala only, while their right amygdala was activated equally by negative and neutral pictures. Correlations of activation in amygdala and visual cortex were observed for both negative and neutral pictures in the controls. In both patient groups, this relationship was attenuated ipsilateral to the TLR. Our results support the notion of reentrant mechanisms between amygdala and visual cortex and suggest laterality differences in their emotion-specificity. While right medial temporal lobe structures including the amygdala seem to influence visual processing in general, the left medial temporal lobe appears to contribute specifically to emotion processing. Still, effects of left TLR on visual emotion processing were relatively subtle. Therefore, hemodynamic correlates of visual emotion processing are likely supported by a distributed cerebral network, challenging an amygdalocentric view of emotion processing.


Asunto(s)
Amígdala del Cerebelo , Lóbulo Temporal , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/fisiología , Amígdala del Cerebelo/cirugía , Emociones/fisiología , Hemodinámica , Humanos , Imagen por Resonancia Magnética/métodos , Estimulación Luminosa/métodos , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiología , Lóbulo Temporal/cirugía
6.
Neuroimage Clin ; 25: 102124, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31884222

RESUMEN

OBJECTIVES: Patients suffering from Takotsubo syndrome have a higher prevalence of anxiety and depressive disorders compared to those with acute myocardial infarction and might thus show impaired regulation and processing of emotions. METHODS: In this cross-sectional study, neural activity during an emotional picture processing task was examined in 26 Takotsubo patients (on average 27 months after the Takotsubo event) and 22 healthy age- and gender-matched control subjects undergoing functional magnetic resonance imaging. Imaging data were analyzed with two complementary approaches: First, univariate analysis was used to detect brain regions showing condition-specific differences in mean neural activity between groups. Second, multivariate pattern analysis was applied to decode the experimental conditions from individual activity patterns. RESULTS: In the univariate analysis approach, patients showed lower bilateral superior parietal activity during the processing of negative expected pictures compared to the control subjects. The multivariate pattern analysis revealed group differences in decoding negative versus neutral pictures from a widespread network consisting of frontal, parietal, occipital, and cerebellar brain regions. Additionally, differences in decoding the expectation of a negative versus positive upcoming picture were observed in the visual cortex. CONCLUSION: The lower involvement of brain regions observed in Takotsubo patients suggests an impairment in emotion regulation, which might be of etiological importance in this brain-heart disease.


Asunto(s)
Emociones/fisiología , Cardiomiopatía de Takotsubo/fisiopatología , Anciano , Trastornos de Ansiedad/epidemiología , Estudios Transversales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
7.
Cogn Affect Behav Neurosci ; 18(6): 1172-1187, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30132268

RESUMEN

Social information is particularly relevant for the human species because of its direct link to guiding physiological responses and behavior. Accordingly, extant functional magnetic resonance imaging (fMRI) data suggest that social content may form a unique stimulus dimension. It remains largely unknown, however, how neural activity underlying social (versus nonsocial) information processing temporally unfolds, and how such social information appraisal may interact with the processing of other stimulus characteristics, particularly emotional meaning. Here, we presented complex visual scenes differing in both social (vs. nonsocial) and emotional relevance (positive, negative, neutral) intermixed with scrambled versions of these pictures to N = 24 healthy young adults. Event-related brain potentials (ERPs) to intact pictures were examined for gaining insight to the dynamics of appraisal of both dimensions, implemented within the brain. Our main finding is an early interaction between social and emotional relevance due to enhanced amplitudes of early ERP components to emotionally positive and neutral pictures of social compared to nonsocial content, presumably reflecting rapid allocation of attention and counteracting an overall negativity bias. Importantly, our ERP data show high similarity with previously observed fMRI data using the same stimuli, and source estimations located the ERP effects in overlapping occipitotemporal brain areas. Our novel data suggest that relevance detection may occur already as early as around 100 ms after stimulus onset and may combine relevance checks not only examining intrinsic pleasantness/emotional valence but also social content as a unique, highly relevant stimulus dimension.


Asunto(s)
Encéfalo/fisiología , Emociones/fisiología , Potenciales Evocados/fisiología , Reconocimiento Facial/fisiología , Percepción Social , Adulto , Atención/fisiología , Mapeo Encefálico , Electroencefalografía , Expresión Facial , Femenino , Humanos , Masculino , Estimulación Luminosa , Adulto Joven
8.
Br J Educ Psychol ; 88(3): 465-479, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29044467

RESUMEN

BACKGROUND AND AIM: The effects of text cohesion and added pictures on acquired knowledge have been heavily studied each in isolation. Furthermore, studies on the effects of specific characteristics of pictures, whether facilitating or hindering, are scarce. Schnotz's ITCP Model (2014) allows to formulate hypotheses regarding the combined effect of text cohesion and presence and level of detail of a picture. This study investigates these hypotheses in the case of children reading scientific texts. SAMPLE: One hundred and one-second-, third-, and fourth-grade pupils with a mean age of 9 years, in the western United States. METHODS: Data were collected over three sessions to encompass an understanding of each pupil's knowledge based on prior sessions. RESULTS AND CONCLUSIONS: Results showed a significant increase in pupils' knowledge between pre-test and immediate post-test, but as hypothesized, no significant difference between levels of cohesion. No significant difference between types of pictures was detected. After 1 week, knowledge built with a high cohesive text significantly dropped with low-detail picture, whereas, with high detail, or no picture, there was no significant difference. Results suggested that when participants were given a low-detail picture with a low cohesive text, the integration process of the material was more restricted than with a high cohesive text.


Asunto(s)
Rendimiento Académico , Recursos Audiovisuales , Reconocimiento Visual de Modelos/fisiología , Lectura , Ciencia/educación , Niño , Femenino , Humanos , Masculino
9.
Conscious Cogn ; 42: 358-365, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27149179

RESUMEN

The impact of anxiety-provoking stimuli on the Sustained Attention to Response Task (SART; Robertson, Manly, Andrade, Baddeley, & Yiend, 1997), and response inhibition more generally, is currently unclear. Participants completed four SARTs embedded with picture stimuli of two levels of emotion (negative or neutral) and two levels of task-relevance (predictive or non-predictive of imminent No-Go stimuli). Negative pictures had a small but detectable adverse effect on performance regardless of their task-relevance. Overall, response times and rates of commission errors were more dependent upon the predictive value (relevance) of the pictures than their attention-capturing nature (i.e., negative valence). The findings raise doubt over whether anxiety improves response inhibition, and also lend support to a response strategy perspective of SART performance, as opposed to a mindlessness or mind-wandering explanation.


Asunto(s)
Ansiedad , Atención/fisiología , Inhibición Psicológica , Reconocimiento Visual de Modelos/fisiología , Desempeño Psicomotor/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Front Psychol ; 5: 686, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25071656

RESUMEN

Cognitive theories on causes of developmental dyslexia can be divided into language-specific and general accounts. While the former assume that words are special in that associated processing problems are rooted in language-related cognition (e.g., phonology) deficits, the latter propose that dyslexia is rather rooted in a general impairment of cognitive (e.g., visual and/or auditory) processing streams. In the present study, we examined to what extent dyslexia (typically characterized by poor orthographic representations) may be associated with a general deficit in visual long-term memory (LTM) for details. We compared object- and detail-related visual LTM performance (and phonological skills) between dyslexic primary school children and IQ-, age-, and gender-matched controls. The results revealed that while the overall amount of LTM errors was comparable between groups, dyslexic children exhibited a greater portion of detail-related errors. The results suggest that not only phonological, but also general visual resolution deficits in LTM may play an important role in developmental dyslexia.

11.
Biol Psychol ; 101: 77-81, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25025638

RESUMEN

Research has demonstrated that late positive potential (LPP) is modulated by affective pictures in school-age children, adolescents and adults. However, little is known about such modulation in specific younger populations such as preschoolers. In this study, we examined whether LPP modulation during affective picture processing would also be observed in preschoolers as well as investigating the patterns of such modulation by using pictures which elicited emotional reactions of different valences. Twenty preschoolers (M age in months=61.00, SD=7.73) passively viewed pleasant, neutral and unpleasant pictures while their scalp event-related potentials (ERPs) were recorded. Results showed that in preschoolers pleasant and unpleasant pictures elicited significantly larger LPP amplitudes than neutral pictures, and this affective modulation of LPP amplitude emerged in the posterior region and gradually extended to the central and anterior regions.


Asunto(s)
Afecto/fisiología , Potenciales Evocados/fisiología , Estimulación Luminosa/métodos , Preescolar , Electroencefalografía/métodos , Emociones , Femenino , Humanos , Masculino
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