157 research outputs found

    Supporting metacognitive monitoring in mathematics learning for young people with autism spectrum disorder: A classroom-based study.

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    Previous research suggests impaired metacognitive monitoring and mathematics under-achievement in autism spectrum disorder. Within educational settings, metacognitive monitoring is supported through the provision of feedback (e.g. with goal reminders and by explicitly correcting errors). Given the strength of the relationship between metacognition, learning and educational attainment, this research tested new computer-based metacognitive support (the 'Maths Challenge') for mathematics learners with autism spectrum disorder within the context of their classroom. The Maths Challenge required learners to engage in metacognitive monitoring before and after answering each question (e.g. intentions and judgements of accuracy) and negotiate with the system the level of difficulty. Forty secondary school children with autism spectrum disorder and 95 typically developing learners completed the Maths Challenge in either a Feedback condition, with metacognitive monitoring support regarding the accuracy of their answers, goal reminders and strategy support, or with No Feedback. Contrary to previous findings, learners with autism showed an undiminished ability to detect errors. They did, however, demonstrate reduced cohesion between their pre- and post-test intentions. Crucially, support from the Feedback condition significantly improved task performance for both groups. Findings highlight important implications for educational interventions regarding the provision of metacognitive support for learners with autism to ameliorate under-performance in mathematics within the classroom

    Advancement of photonic integration technology for space applications: A x-band scan-on-receive synthetic aperture radar receiver with electro-photonic beamforming and frequency downconversion capability

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    Synthetic Aperture Radar is a well-known technique for remote sensing applications with great advantages like uninterrupted imaging capabilities even at night or in presence of cloud cover. However, spaceborne SAR sensors face major challenges such as cost and size, which are among the barriers against their applicability for future constellations of low-Earth observation applications. SAR sensors are not compact and require large or medium-sized satellites, which cost hundreds million dollars. To solve these challenges, the recently started SPACEBEAM project, funded by the European Commission, aims at developing a novel SAR Scan-on-Receive approach, exploiting a hybrid integrated optical beamforming network (iOBFN). The compactness and frequency flexibility of the proposed photonic solution complies with the requirements of future constellations of low-Earth orbit satellites in terms of size, weight, power consumption, and cost (SWaP-C). In the design of the SCORE SAR receiver module, we target the development of an X-band receiver having a large swath width of 50 km (5 times wider than state-of-art spaceborne SAR systems), although at the same time enabling a fine spatial resolution of 1.5 m in both along-track and across-track directions. In this paper, we present specifications and preliminary design of the SCORE-SAR receiver at equipment level, where we aim at the realization of a hermetically packaged hybrid InP/TriPleX™ photonic integrated circuit (PIC) for this application. We target the design for the PIC as well as for the RF front-end and control electronics, enabling the electro-photonic frequency down-conversion of the RF signals and the fast control of iOBFN with <300 ns switching time

    Design and Performance Estimation of a Photonic Integrated Beamforming Receiver for Scan-On-Receive Synthetic Aperture Radar

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    Synthetic aperture radar is a remote sensing technology finding applications in a wide range of fields, especially related to Earth observation. It enables a fine imaging that is crucial in critical activities, like environmental monitoring for natural resource management or disasters prevention. In this picture, the scan-on-receive paradigm allows for enhanced imaging capabilities thanks to wide swath observations at finer azimuthal resolution achieved by beamforming of multiple simultaneous antenna beams. Recently, solutions based on microwave photonics techniques demonstrated the possibility of an efficient implementation of beamforming, overcoming some limitations posed by purely electronic solutions, offering unprecedented flexibility and precision to RF systems. Moreover, photonics-assisted RF beamformers can nowadays be realized as integrated circuits, with reduced size and power consumption with respect to digital beamforming approaches. This paper presents the design analysis and the challenges of the development of a hybrid photonic-integrated circuit as the core element of an X-band scan-on-receive spaceborne synthetic aperture radar. The proposed photonic-integrated circuit synthetizes three simultaneous scanning beams on the received signal, and performs the frequency down-conversion, guaranteeing a compact 15 cm2-form factor, less than 6 W power consumption, and 55 dB of dynamic range. The whole photonics-assisted system is designed for space compliance and meets the target application requirements, representing a step forward toward a deeper penetration of photonics in microwave applications for challenging scenarios, like the observation of the Earth from space

    Early numerical competencies in 5- and 6-year-old children with autism spectrum disorder

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    Research Findings: To date, studies comparing the mathematical abilities of children with autism spectrum disorder (ASD) and typically developing children are scarce, and results remain inconclusive. In general, studies on this topic focus on mathematical abilities learned from elementary school onward, with little attention for possible precursors at younger ages. The current exploratory study focused on the important developmental period of preschool age, investigating 5 early numerical competencies in 30 high-functioning children with ASD and 30 age-matched control children: verbal subitizing, counting, magnitude comparison, estimation, and arithmetic operations. Children were examined at 5 or 6 years of age, attending the 3rd and final year of preschool. Overall, rather similar early number processing was found in children with and without ASD, although marginally significant results indicated a weaker performance of children with ASD on verbal subitizing and conceptual counting. Practice or Policy: Given the pervasiveness and impact of ASD on other domains of functioning, it is important to know that no general deficits in early numerical competencies were found in this study. However, some downward trends in mathematics performance were identified in children with ASD, which can serve as the basis for additional research in this field

    Design and performance estimation of a photonic integrated beamforming receiver for scan-on-receive synthetic aperture radar

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    Synthetic aperture radar is a remote sensing technology finding applications in a wide range of fields, especially related to Earth observation. It enables a fine imaging that is crucial in critical activities, like environmental monitoring for natural resource management or disasters prevention. In this picture, the scan-on-receive paradigm allows for enhanced imaging capabilities thanks to wide swath observations at finer azimuthal resolution achieved by beamforming of multiple simultaneous antenna beams. Recently, solutions based on microwave photonics techniques demonstrated the possibility of an efficient implementation of beamforming, overcoming some limitations posed by purely electronic solutions, offering unprecedented flexibility and precision to RF systems. Moreover, photonics-assisted RF beamformers can nowadays be realized as integrated circuits, with reduced size and power consumption with respect to digital beamforming approaches. This paper presents the design analysis and the challenges of the development of a hybrid photonic-integrated circuit as the core element of an X-band scan-on-receive spaceborne synthetic aperture radar. The proposed photonic-integrated circuit synthetizes three simultaneous scanning beams on the received signal, and performs the frequency down-conversion, guaranteeing a compact 15 cm2-form factor, less than 6 W power consumption, and 55 dB of dynamic range. The whole photonics-assisted system is designed for space compliance and meets the target application requirements, representing a step forward toward a deeper penetration of photonics in microwave applications for challenging scenarios, like the observation of the Earth from space

    Cognitive Profile of Students Who Enter Higher Education with an Indication of Dyslexia

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    For languages other than English there is a lack of empirical evidence about the cognitive profile of students entering higher education with a diagnosis of dyslexia. To obtain such evidence, we compared a group of 100 Dutch-speaking students diagnosed with dyslexia with a control group of 100 students without learning disabilities. Our study showed selective deficits in reading and writing (effect sizes for accuracy between d = 1 and d = 2), arithmetic (d≈1), and phonological processing (d>0.7). Except for spelling, these deficits were larger for speed related measures than for accuracy related measures. Students with dyslexia also performed slightly inferior on the KAIT tests of crystallized intelligence, due to the retrieval of verbal information from long-term memory. No significant differences were observed in the KAIT tests of fluid intelligence. The profile we obtained agrees with a recent meta-analysis of English findings suggesting that it generalizes to all alphabetic languages. Implications for special arrangements for students with dyslexia in higher education are outlined

    Preschoolers' Precision of the Approximate Number System Predicts Later School Mathematics Performance

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    The Approximate Number System (ANS) is a primitive mental system of nonverbal representations that supports an intuitive sense of number in human adults, children, infants, and other animal species. The numerical approximations produced by the ANS are characteristically imprecise and, in humans, this precision gradually improves from infancy to adulthood. Throughout development, wide ranging individual differences in ANS precision are evident within age groups. These individual differences have been linked to formal mathematics outcomes, based on concurrent, retrospective, or short-term longitudinal correlations observed during the school age years. However, it remains unknown whether this approximate number sense actually serves as a foundation for these school mathematics abilities. Here we show that ANS precision measured at preschool, prior to formal instruction in mathematics, selectively predicts performance on school mathematics at 6 years of age. In contrast, ANS precision does not predict non-numerical cognitive abilities. To our knowledge, these results provide the first evidence for early ANS precision, measured before the onset of formal education, predicting later mathematical abilities

    Learning from learning logs: A case study of metacognition in the primary school classroom

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    Structured thinking activities (STAs) are pedagogical tools used to support metacognition in classrooms. Despite their popularity, little is known about how pupils use STAs as platforms to think about and manage their own thinking (i.e. as metacognitive tools). This case study investigated pupils’ use of STAs in relation to metacognition throughout a school year. We focus on two 8‐year‐old pupils, Amy and Laura, as they completed two specific STAs through weekly class meets and termly achievement logs. Data were triangulated through participant observation, qualitative interviews and analysis of written texts. We found clear differences between Laura's and Amy's written STAs, however observation and interviews revealed that engagement with STAs was similar beyond that suggested by the written evidence alone. Whereas Amy used easily spelt ‘stock’ responses, Laura used ‘bare minimum’ responses to meet teacher expectations. As such, neither Amy nor Laura used STAs as metacognitive tools, however in negotiating STAs, both exhibited strategic regulatory skills indicative of metacognition. Whilst our findings highlight that pupils may still be developing explicit metacognitive knowledge necessary to take full advantage of STAs, we highlight the clear value of persistent approaches to using STAs as tools to support developing metacognition, particularly in association with teacher–pupil interactions
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