1000 resultados para Video Forensic


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background:
Research has examined the energy cost associated with playing seated and active video games (AVGs), but not whether AVGs may benefit fundamental movement skills (FMS) in typically developing children. Improving FMS proficiency is a priority given its association with physical activity. This study aimed to identify children’s and parents’ perceptions of: (1) AVGs as a tool for developing FMS and (2) whether any skills gained during AVG play had potential to transfer to real life.

Methods:
This qualitative descriptive study included 29 parents of children aged 9–10 years who participated in semi-structured telephone interviews and 34 children who participated in six group discussions at school. Interview and discussion group data were recorded, transcribed and analysed thematically.

Results:
Parents and children had different perspectives on the potential of AVGs for FMS, which largely rested on different views of ‘reality’. Parents felt AVGs were not a substitute for the ‘real thing’, and therefore had limited FMS benefits. Overall, parents thought any FMS gained through AVGs would have poor transferability to ‘real life’. In contrast, children had a more fluid and expansive view of reality which incorporated both ‘real life’ and ‘virtual’ space. Whilst children could articulate limitations of AVGs for skill learning, they still reported extensive use of AVGs as a learning tool for movement skill, and considered that skill acquisition was highly transferable.

Conclusions:
Despite contrasting beliefs from parents and children, children used AVGs for FMS learning. Future research needs to determine whether actual FMS benefits are gained through AVGs.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Design-based research has gained currency in educational research over the past decade due to its strength to bridge the divide between theoretical research and educational practice in naturalistic settings. Design based approaches involve a process of designing mathematical tasks, observing the enacted design in classrooms and reflecting on the process from analysing the classroom artifacts. Video plays a central role in supporting teachers and teacher educators to study and reflect on students’ mathematical thinking and in capturing the dynamic of classroom teaching and learning process.

This chapter will examine and analyse practitioner’s lenses in capturing the dynamic and complexity of classroom mathematical learning using video segments, and classroom artifacts including digital photos of classroom moments and students’ work. Practitioners’ lenses are taken as a window to capture key teaching and learning moments from the lessons. Analysis of this selection of these video segments along with other classroom artifacts based on practitioners’ lenses provide insights into practitioners’ views on key teaching and learning moments in mathematics lessons.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

With urbanization and vehicle availability, there exist many traffic problems including congestion, environmental impact and safety. In order to address these problems, we propose a video driven traffic modelling system in this paper. The system can simulate real-world traffic activities in a computer, based on traffic data recorded in videos. Video processing is employed to estimate metrics such as traffic volumes. These metrics are used to update the traffic system model, which is then simulated using the Paramics™ traffic simulation platform. Video driven traffic modelling has widespread potential application in traffic systems, due to the convenience and reduced costs of model development and maintenance. Experiments are conducted in this paper to demonstrate the effectiveness of the proposed system.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: This naturalistic study tests whether children receiving a new (to them) active video game spontaneously engage in more physical activity than those receiving an inactive video game, and whether the effect would be greater among children in unsafe neighborhoods, who might not be allowed to play outside.

METHODS: Participants were children 9 to 12 years of age, with a BMI >50th percentile, but <99th percentile; none of these children a medical condition that would preclude physical activity or playing video games. A randomized clinical trial assigned children to receiving 2 active or 2 inactive video games, the peripherals necessary to run the games, and a Wii console. Physical activity was monitored by using accelerometers for 5 weeks over the course of a 13-week experiment. Neighborhood safety was assessed with a 12 item validated questionnaire.

RESULTS: There was no evidence that children receiving the active video games were more active in general, or at anytime, than children receiving the inactive video games. The outcomes were not moderated by parent perceived neighborhood safety, child BMI z score, or other demographic characteristics.

CONCLUSIONS: These results provide no reason to believe that simply acquiring an active video game under naturalistic circumstances provides a public health benefit to children.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: A population level increase in physical activity (PA) is critical to reduce obesity in youth. Video games are highly popular and active video games (AVGs) have the potential to play a role in promoting youth PA.

Method: Studies on AVG play energy expenditure (EE) and maintenance of play in youth were systematically identified in the published literature and assessed for quality and informational value.

Results: Nine studies measuring AVG play EE were identified. The meta-analytic estimates of average METs across these studies were 3.1 (95% CI: 2.6, 3.6) to 3.2 (95% CI: 2.7, 3.7). No games elicited an average EE above the 6 MET threshold for vigorous EE. Observed differences between studies were likely due to the different types of games used, rather than age or gender. Four studies related to maintenance of play were identified. Most studies reported AVG use declined over time. Studies were of low-to-medium quality.

Conclusion: AVGs are capable of generating EE in youth to attain PA guidelines. Few studies have assessed sustainability of AVG play, which appears to diminish after a short period of time for most players. Better-quality future research must address how AVG play could be maintained over longer periods of time.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In her paper Gwen Adshead (2013) identifies the principle of respect for justice as the foundation for ethical practice in forensic psychiatry. This commentary discusses how forensic psychologists have approached a key aspect of the justice principle, the ethical imperative to promote the welfare of the individual client. The approaches of the psychiatric and psychological professions are compared and the role of psychologists as allied health professionals working in the forensic setting considered.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We propose Video Driven Traffic Modelling (VDTM) for accurate simulation of real-world traffic behaviours with detailed information and low-cost model development and maintenance. Computer vision techniques are employed to estimate traffic parameters. These parameters are used to build and update a traffic system model. The model is simulated using the Paramics traffic simulation platform. Based on the simulation techniques, effects of traffic interventions can be evaluated in order to achieve better decision makings for traffic management authorities. In this paper, traffic parameters such as vehicle types, times of starting trips and corresponding origin-destinations are extracted from a video. A road network is manually defined according to the traffic composition in the video, and individual vehicles associated with extracted properties are modelled and simulated within the defined road network using Paramics. VDTM has widespread potential applications in supporting traffic decision-makings. To demonstrate the effectiveness, we apply it in optimizing a traffic signal control system, which adaptively adjusts green times of signals at an intersection to reduce traffic congestion.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We report the development of an affective domain instrument for the assessment of undergraduate students’ attitudes toward forensic science. Assessment of attitudes of the respondents is important to understand mediating factors in student motivation and ultimately success in the discipline. The instrument was developed using an iterative process based on responses from an expert panel of Australian forensic science educators to an array of forensic science and teaching related topics, and refined using further feedback from the panel on more specific items. The layout of the instrument, with regard to both the wording and placement of items, was developed with regular test takers (i.e., students) in mind and through the application of basic psychometric principles. The engagement of forensic science colleagues across Australia has resulted in an outcome that could provide a source of credible and relevant evidence of student attitudes toward forensic science.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

As a problem of high practical appeal but outstanding challenges, computer-based face recognition remains a topic of extensive research attention. In this paper we are specifically interested in the task of identifying a person from multiple training and query images. Thus, a novel method is proposed which advances the state-of-the-art in set based face recognition. Our method is based on a previously described invariant in the form of generic shape-illumination effects. The contributions include: (i) an analysis of computational demands of the original method and a demonstration of its practical limitations, (ii) a novel representation of personal appearance in the form of linked mixture models in image and pose-signature spaces, and (iii) an efficient (in terms of storage needs and matching time) manifold re-illumination algorithm based on the aforementioned representation. An evaluation and comparison of the proposed method with the original generic shape-illumination algorithm shows that comparably high recognition rates are achieved on a large data set (1.5% error on 700 face sets containing 100 individuals and extreme illumination variation) with a dramatic improvement in matching speed (over 700 times for sets containing 1600 faces) and storage requirements (independent of the number of training images).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We consider the problem of matching a face in a low resolution query video sequence against a set of higher quality gallery sequences. This problem is of interest in many applications, such as law enforcement. Our main contribution is an extension of the recently proposed Generic Shape-Illumination Manifold (gSIM) framework. Specifically, (i) we show how super-resolution across pose and scale can be achieved implicitly, by off-line learning of subsampling artefacts; (ii) we use this result to propose an extension to the statistical model of the gSIM by compounding it with a hierarchy of subsampling models at multiple scales; and (iii) we describe an extensive empirical evaluation of the method on over 1300 video sequences – we first measure the degradation in performance of the original gSIM algorithm as query sequence resolution is decreased and then show that the proposed extension produces an error reduction in the mean recognition rate of over 50%.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In spite of over two decades of intense research, illumination and pose invariance remain prohibitively challenging aspects of face recognition for most practical applications. The objective of this work is to recognize faces using video sequences both for training and recognition input, in a realistic, unconstrained setup in which lighting, pose and user motion pattern have a wide variability and face images are of low resolution. In particular there are three areas of novelty: (i) we show how a photometric model of image formation can be combined with a statistical model of generic face appearance variation, learnt offline, to generalize in the presence of extreme illumination changes; (ii) we use the smoothness of geodesically local appearance manifold structure and a robust same-identity likelihood to achieve invariance to unseen head poses; and (iii) we introduce an accurate video sequence “reillumination” algorithm to achieve robustness to face motion patterns in video. We describe a fully automatic recognition system based on the proposed method and an extensive evaluation on 171 individuals and over 1300 video sequences with extreme illumination, pose and head motion variation. On this challenging data set our system consistently demonstrated a nearly perfect recognition rate (over 99.7%), significantly outperforming state-of-the-art commercial software and methods from the literature