Zoekresultaten

The duration of automation bias in a realistic setting

Whereas in most studies conducted previously the effect of automation bias has been investigated in terms of an instantaneous decision, this study is aimed at quantifying its duration.

MIMU PDR with bias estimation using an optimization-based approach.

Traditional IMU based PDR systems suffer from rapidly growing drift effects due to the inherent bias of the inertial sensor. Many existing solutions to mitigate this problem use aiding sensors or information as heuristics or map data. We propose a new optimization framework to solve the PDR estimation problem where the sensors biases are explicitly included as state variables and therefore be used to correct for bias effects in the PDR. By using a smoothing approach and exploiting the rigid structure of a MIMU array one can solve for the slowly varying sensor biases. This paper presents the method and gives an exemplary result of a walking trial. Good agreements in the position and orientation with an optical reference system were found. Moreover, accelerometer and gyroscope biases could be estimated accordingly. Further research includes the performance of more experiments under various conditions such that a more quantitative evaluation can be obtained. In addition, an exploration of a (pseudo) realtime filter version would be valuable such that the system can be applied online.

Machine Vision and Social Media Images: Why Hashtags Matter

Studying images in social media poses specific methodological challenges, which in turn have directed scholarly attention toward the computational interpretation of visual data. When analyzing large numbers of images, both traditional content analysis as well as cultural analytics have proven valuable. However, these techniques do not take into account the contextualization of images within a socio-technical environment. As the meaning of social media images is co-created by online publics, bound through networked practices, these visuals should be analyzed on the level of their networked contextualization. Although machine vision is increasingly adept at recognizing faces and features, its performance in grasping the meaning of social media images remains limited. Combining automated analyses of images with platform data opens up the possibility to study images in the context of their resonance within and across online discursive spaces. This article explores the capacities of hashtags and retweet counts to complement the automated assessment of social media images, doing justice to both the visual elements of an image and the contextual elements encoded through the hashtag practices of networked publics.

Uncovering bias in the PlantVillage dataset.

The Bidirectional Relationship between Vision and Cognition: A Systematic Review and Meta-analysis

Topic: Visual impairment (VI) and cognitive impairment (CIM) are prevalent age-related conditions that impose substantial burden on the society. Findings on the hypothesized bidirectional association of VI and CIM remains equivocal. Hence, we conducted a systematic review and meta-analysis to examine this bidirectional relationship. Clinical relevance: Sixty percent risk of CIM has not been well elucidated in the literature. A bidirectional relationship between VI and CIM may support the development of strategies for early detection and management of risk factors for both conditions in older people. Methods: PubMed, Embase, and Cochrane Central registers were searched systematically for observational studies, published from inception until April 6, 2020, in adults 40 years of age or older reporting objectively measured VI and CIM assessment using clinically validated cognitive screening tests or diagnostic evaluation. Meta-analyses on cross-sectional and longitudinal associations between VI and CIM outcomes (any CIM assessed using screening tests and clinically diagnosed dementia) were examined. Random effect models were used to generate pooled odds ratios (ORs) and 95% confidence intervals (CIs). We also examined study quality, publication bias, and heterogeneity. Results: Forty studies were included (n = 47 913 570). Meta-analyses confirmed that persons with VI were more likely to have CIM, with significantly higher odds of: (1) any CIM (cross-sectional: OR, 2.38 [95% CI, 1.84-3.07]; longitudinal: OR, 1.66 [95% CI, 1.46-1.89]) and (2) clinically diagnosed dementia (cross-sectional: OR, 2.43 [95% CI, 1.48-4.01]; longitudinal: OR, 2.09 [95% CI, 1.37-3.21]) compared with persons without VI. Significant heterogeneity was explained partially by differences in age, sex, and follow-up duration. Also, some evidence suggested that individuals with CIM, relative to cognitively intact persons, were more likely to have VI, with most articles (8/9 [89%]) reporting significantly positive associations; however, meta-analyses on this association could not be conducted because of insufficient data. Discussion: Overall, our work suggests that VI is a risk factor of CIM, although further work is needed to confirm the association of CIM as a risk factor for VI. Strategies for early detection and management of both conditions in older people may minimize individual clinical and public health consequences.

Diplopie door monovisie

Doelstelling: In kaart brengen van de risicofactoren voor het ontwikkelen van binoculaire diplopie na conventionele monovisie door middel van contactlenzen of refractiechirurgie bij presbyopen. Methode: Voor deze literatuurstudie is in maart 2017 gezocht in databanken Pubmed, ScienceDirect en Google Scholar. Artikelen zijn geïncludeerd als binoculaire diplopie door monovisie wordt beschreven. Alle patiënten die worden weergegeven in deze artikelen zijn ouder dan 40 jaar en hebben monovisie door middel van contactlenzen of refractiechirurgie. De resultaten beschrijven de oorzaken van de binoculaire diplopie, de voorgeschiedenis van de patiënt met betrekking tot strabismus en de hoogte van additie. Onderscheid wordt gemaakt tussen contactlensdragers en patiënten die refractiechirurgie hebben ondergaan. Resultaten: In deze literatuurstudie zijn zes artikelen verwerkt. Uit deze artikelen zijn 35 patiënten met binoculaire diplopie meegenomen in dit onderzoek, vijftien patiënten met contactlens geïnduceerde monovisie en twintig patiënten met refractiechirurgie geïnduceerde monovisie. De oorzaken van binoculaire diplopie (decompensatie van een heteroforie, een intermitterend strabismus die constant wordt, een verworven heterotropie, decompensatie van een N IV parese en fixation switch diplopie) geven geen grote verschillen in aantal patiënten. Een additie hoger dan twee dioptrie komt meer voor in deze patiëntengroep met binoculaire diplopie dan een lagere additie. Een positieve voorgeschiedenis met betrekking tot strabismus komt meer voor dan een negatieve voorgeschiedenis. Relevante verschillen tussen contactlensdragers en patiënten die refractiechirurgie hebben ondergaan zijn niet gevonden. Conclusie: Vanwege het gebrek aan consistente data is meer onderzoek nodig voor significante resultaten.